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RoHan DAAD SDG Workshop 2018 “Catalysis toward sustainable chemical industry”

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CONTENT

Time Content Page

Monday 17.9.2018

10:30 Biocatalytic reaction for synthesis of fine and bulk chemicals - Prof. Udo Kragl - UR

60

11:30 Isospecific Ring-Opening Polymerization and Copolymerization of Racemic Epoxides with Dialkylmagnesium Reagents - Dr. Esteban Mejía - LIKAT

9

Topic: Sustainable catalysis

14:00 Sustainability, Environmental Economics, and Catalytic Chemistry - Prof. Michael Rauscher - UR

10

15:00 Sustainable Ru-catalyzed Methylation of Amines and Carbonyl Compounds using Methanol as a Green Alkylating Reagent - Dr. Tuan Thanh Dang - VNU-HUS

11

16:00 Promotion study on Ni catalysts for CH4 rich DRM - Quan Luu Manh Ha - LIKAT 12

16:30 CO2 capture on amine-impregnated solid sorbents - Dr. Dao Sy Duc - VNU-HUS 13

17:00 Methanation of CO2 on Ni/Al2O3 in Structured Reactors. A Scale-Up Study from Lab to Industry Application - Dr. Hesham Mena LIKAT

14

Tuesday 18.9.2018

9:00 Computational guided design of catalyst for sustainable and green energy - Dr. Trinh Quang Thang - NTU Singapore

15

Topic: Catalysis Characterization

10:30 Investigations of the Manganese Catalyzed CO2 Reduction probed by IR Spectroscopy - Elisabeth Oberem - UR

16

11:00 EPR spectroscopy - a necessary tool for investigation of charge-transfer processes - Dr. Dirk Hollmann - UR

17

11:30 TPX methods for characterization of heterogeneous catalysts - Dr. Hanan Atia - LIKAT

18

Topic: Photocatalysis

14:00 New Photocatalytic Reactions: Oxidative, Reductive and Tandem Transformations - Prof. Malte Brasholz - UR

19

15:00 Preparation of TiO2 nano material coating on rice husk ash and application for nitrohen compound removal from industrial wastewater - Prof. Nguyen Thi Ha - VNU-HUS

20

16:00 pH dependence in the formation of tin oxide based photocatalyst and its photocatalytic degradation of direct blue 71 (DB71) - Dr. Ha Minh Ngoc - VNU-

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HUS

16:30 Preparation of porous materials ZnO/AC and ZnO/SiO2 from rice husk for photo-degradation of organic dyes in wastewater - Dr. Vu Anh Tuan - HUST

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Wednesday 19.9.2018

9:00 Current status and strategy of catalysis for oil and gas processing in Vietnam – Dr. Dang Thanh Tung - VPI Hanoi

Topic: Industrial catalysis

10:30 Acidic modifying of natural Zeolite to Etherification and Acetalization reaction in Green Chemistry - Do Trung Hieu -UR

23

11:00 Influence of boron on the bronsted and lewis acid sites of sba-15 and pt/sba-15 catalyst for the hydrogenation of tetralin - Ngo Thi Thanh Hien - HUST

24

11:30 Preparation and characterization of hierarchical ZSM-5 materials for enhanced cracking of 1, 3, 5 - triisopropylbenzene at low temperature - Vu Xuan Hoan - VPI

25

Topic: Catalysis in bio waste

14:00 Sustainable biorefinery concept focusing valorization and cascading of Vietnamese lignocellulose waste - Dr. Andrea Schüch - UR

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15:00 Applied carbon-based solid acid catalyst from waste wood apply for 5-HMF synthesis - Dr. Nguyen Trung Thanh - HUST

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16:00 Toward bio-based polyamides - methyl pentenoate production in a continuous gas phase process - Annemarie Marckwordt - LIKAT

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Thursday 20.9.2018

9:00 Prof. Huynh Dang Chinh - HUST

Topic: Oxidation catalysis

10:30 Carbene/Manganese catalyzed oxidative esterification of 5Hydroxymethylfurural - Albel David Salazar La Rosa - LIKAT

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11:00 Phenazine Radical Cations as Metal-Free Catalysts for Aerobic Oxidations - Felix Unglaube - LIKAT

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11:30 Liquid Oxidation of styrene Mg-Cu-Al Layered Double Hydroxide Catalysts - Prof. Nguyen Tien Thao - VNU-HUS

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14:00 A light touch: Photo-mediated Functionalization of Organic Molecules - Dr.Jola Pospech - LIKAT

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15:00 Synthesis of N-dopped TiO2 nanotube material towards application for VOCs treatment - Nguyen Hai Minh - VNU-HUS

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16:00 Ennhanced photocatalytic degradation of Rhodamine B in aqueous solutions using CeO2/GO photocatalysts - Dr. Tran Dinh Trinh - VNU-HUS

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16:30 Synthesis and application of Ag/TiO2 for the photocatalytic treatment of Cr(VI) in water under visible light - Tran Thi Kieu Trinh - HUST

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Friday 21.9.2018

9:00 EPR spectrometer concepts - Mr. Kwanchai Khongwattananon - Brucker

Topic: Air Treatment

10:30 Synergistic effect of VOx and MnOx surface species for improved performance of

V2O5/Ce0.5Ti0.5-xMnxO2- catalysts in low-temperature NH3-SCR of NO - Dr. Huyen Vuong - LIKAT

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11:00 Small Pore Zeolite Catalysts for the Selective Catalytic Reduction of Nox - Pham Trong - VNU-HUS

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11:30 Investigation of liquid-phase CO adsorption on Pd nanoparticles supported on doped TiO2 - Pawel Naliwajko - LIKAT

38

14:00 Basics of BET Measurement and some Examples for Preparation of micro- and mesoporous Materials - Reinhard Eckelt - LIKAT

39

14:30 Modification of Vietnam natural rubber via grafting copolymerization with styrene - Dr. Tran Thi Thuy - HUST

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LIST OF POSTER

No Content Page

1 Characterization of Hydrogenated Natural Rubber Prepared through Nano-particle Hydrogenation in Latex Stage - Nguyen Thu Ha - HUST

42

2 Separation of Fischer-Tropsch alkanes from methane by mesoporous silica membranes - Thu Hong Anh Ngo - VNU-HUS

43

3 Development of graphitic carbon nitride (g-C3N4) - based materials for visible light dye degradation - Vu Viet Thang - HUST

44

4 TEMPO and Poly(TEMPO) catalysts for electrosynthesis of benzonitrile from benzyl alcohol - Dr. Tran Thi Luyen - HUST

45

5 Degradation of cephalexin by heterogeneous Fenton catalyst using iron-modified fly ash - Dr.Ing. Dao Sy Duc - VNU-HUS

46

6 A synchrotron X-ray diffraction study of the adsorption of CO2 in KFI zeolite - Pham Trong - VNU-HUS

47

7 Investigation of phenol adsorption by using amine-modified biochar beads - Nguyen Viet Minh - VNU-HUS

48

8 Synthesis of 3D rGO - Nanoparticles Composite by Hydrothermal Method and its catalyst ability in oxidation of Methylene Blue - Nguyen Thi Hang - VNU-HUS

49

9 Synthesis of novel monomers from 5-hydroxymethylfurdural (HMF) for the production of bio-based polymeric materials - Nguyen Duy Hieu - HUST

50

10 Study in toluen oxidation over catalysts of CoxCuyOz on different supports - Ngo Quoc Khanh - HUST

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11 Synthesis of polycaprolactone by using magnesium compounds as catalysts - Nguyen Thi Nhan - HUST

52

12 A Research on impact of structural directing agent and synthesis conditions to the formation of SAPO structure - Doan Anh Tuan - HUST

53

13 The formation of Rh-complexes and deactivation of supported ionic liquid phase (SILP) catalysts in hydroformylation of ethylene - Truong Duc Duc - HUST

54

14 Efficient Synthesis of 5- and 6-azaindoles by Sequential Site-selective Pd-catalyzed C-C and C-N coupling reactions - Nguyen Thi Son - VNU-HUS

55

15 Synthesis nano TiO2-GO powder and TiO2 thin film by Sol-gel and Chemical Vapor Deposition methods for Methyl Orange Photocatalytic degradation in full range and UV light condition - Nguyen Trung Hieu - HUST

56

16 The influence of Co, Mo on CuO doped catalysts for the direct conversion of methane - Pham Thi Mai Phuong - HUST

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17 Aromatization of n-hexane over Zn-modified nano-ZSM-5 zeolite catalyst - Vu Dinh Trinh - Nghi Son Refinery and Petrochemical Limited Liability Company

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18 Synthesis and characterization of composites x% g-C3N4/TiO2 - Nguyen Thanh Binh - VNU

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PROGRAM

Monday 17.9.2018 Tuesday 18.9.2018 Wednesday 19.9.2018 Thursday 20.9.2018 Friday 21.9.2018

9:00 Opening - Prof Udo Kragl (UR), Mr Stefan Hase-Bergen (Director of the DAAD Southeast Asia Regional Office), Prof. Hoang Minh Son – HUST, Prof. Nguyen Van Noi - VNU-HUS,

9:00 Computational guided design of catalyst for sustainable and green energy - Dr. Trinh Quang Thang - NTU Singapore

9:00 Current status and strategy of catalysis for oil and gas processing in Vietnam – Dr. DangThanh Tung - VPI Hanoi

9:00 Prof. Huynh Dang Chinh, Prof. Nguyen Hong Lien - HUST

9:00 EPR spectrometer concepts - Mr. Kwanchai Khongwattananon - Brucker

10:00 Coffee break 10:00 Coffee break 10:00 Coffee break 10:00 Coffee break 10:00 Coffee break

Topic: Catalysis Characterization

Topic: Industrial catalysis

Topic: Oxidation catalysis

Topic: Air Treatment

10:30 Biocatalytic reaction for synthesis of fine and bulk chemicals - Prof. Udo Kragl - UR

10:30 Investigations of the Manganese Catalyzed CO2 Reduction probed by IR Spectroscopy - Elisabeth Oberem - UR

10:30 Acidic modifying of natural Zeolite to Etherification and Acetalization reaction in Green Chemistry - Do Trung Hieu -UR

10:30 Carbene/Manganese catalyzed oxidative esterification of 5Hydroxymethylfurural -Albel David Salazar La Rosa - LIKAT

10:30 Synergistic effect of VOx and MnOx surface species for improved performance of V2O5/Ce0.5Ti0.5

-xMnxO2-d catalysts in low-temperature NH3-SCR of NO - Dr. Huyen Vuong - LIKAT

11:00 EPR spectroscopy - a necessary tool for investigation of charge-transfer processes - Dr. Dirk Hollmann - UR

11:00 Influence of boron on the bronsted and lewis acid sites of sba-15 and pt/sba-15 catalyst for the hydrogenation of tetralin - Ngo Thi Thanh Hien - HUST

11:00 Phenazine Radical Cations as Metal-Free Catalysts for Aerobic Oxidations - Felix Unglaube - LIKAT

11:00 Small Pore Zeolite Catalysts for the Selective Catalytic Reduction of Nox - Pham Trong - VNU-HUS

11:30 Isospecific Ring-Opening Polymerization and Copolymerization of Racemic Epoxides with Dialkylmagnesium Reagents - Dr. Esteban Mejía - LIKAT

11:30 TPX methods for characterization of heterogeneous catalysts - Dr. Hanan Atia - LIKAT

11:30 Preparation and characterization of hierarchical ZSM-5 materials for enhanced cracking of 1, 3, 5 - triisopropylbenzene at low temperature - Vu Xuan Hoan - VPI

11:30 Liquid Oxidation of styrene Mg-Cu-Al Layered Double Hydroxide Catalysts - Prof. Nguyen Tien Thao - VNU-HUS

11:30 Investigation of liquid-phase CO adsorption on Pd nanoparticles supported on doped TiO2 - Pawel Naliwajko - LIKAT

12:00 Lunch break 12:00 Lunch break 12:00 Lunch break 12:00 Lunch break 12:00 Lunch break


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Topic: Sustainable catalysis


Topic: Catalysis in bio waste


14:00 Sustainability, Environmental Economics, and Catalytic Chemistry - Prof. Michael Rauscher - UR

14:00 New Photocatalytic Reactions: Oxidative, Reductive and Tandem Transformations - Prof. Malte Brasholz - UR

14:00 Sustainable biorefinery concept focusing valorization and cascading of Vietnamese lignocellulose waste - Dr. Andrea Schüch - UR

14:00 A light touch: Photo-mediated Functionalization of Organic Molecules - Dr.Jola Pospech - LIKAT

14:00 Basics of BET Measurement and some Examples for Preparation of micro- and mesoporous Materials Reinhard Eckelt LIKAT

14:30 Modification of Vietnam natural rubber via grafting copolymerization with styrene - Dr. Tran Thi Thuy - HUST

15:00 Sustainable Ru-catalyzed Methylation of Amines and Carbonyl Compounds using Methanol as a Green Alkylating Reagent - Dr. Tuan Thanh Dang - VNU-HUS

15:00 Preparation of TiO2 nano material coating on rice husk ash and application for nitrohen compound removal from industrial wastewater - Prof. Nguyen Thi Ha - VNU-HUS

15:00 Applied carbon-based solid acid catalyst from waste wood apply for 5-HMF synthesis - Dr. Nguyen Trung Thanh - HUST

15:00 Synthesis of N-dopped TiO2 nanotube material towards application for VOCs treatment - Nguyen Hai Minh - VNU-HUS

15:00 Summary

15:30 Coffee break 15:30 Coffee break 15:30 Coffee break 15:30 Coffee break

16:00 Promotion study on Ni catalysts for CH4 rich DRM - Quan Luu Manh Ha - LIKAT

16:00 Enhanced photocatalytic degradation of Rhodamine B in aqueous solutions using CeO2/GO photocatalysts - Dr. Tran Dinh Trinh - VNU-HUS

16:00 Toward bio-based polyamides – methyl pentenoate production in a continuous gas phase process - Annemarie Marckwordt - LIKAT

16:00 pH dependence in the formation of tin oxide based photocatalyst and its photocatalytic degradation of direct blue 71 (DB71) - Dr. Ha Minh Ngoc - VNU-HUS

16:30 CO2 capture on amine-impregnated solid sorbents - Dr. Dao Sy Duc - VNU-HUS

16:30 Preparation of porous materials ZnO/AC and ZnO/SiO2 from rice husk for photo-degradation of organic dyes in wastewater - Dr. Vu Anh Tuan - HUST

16:30 Poster section and Introduction about ROHAN labs

16:30 Synthesis and application of Ag/TiO2 for the photocatalytic treatment of Cr(VI) in water under visible light - Tran Thi Kieu Trinh - HUST

17:00 Methanation of CO2 on Ni/Al2O3 in Structured Reactors. A Scale-Up Study from Lab to Industry Application - Dr. Hesham Mena LIKAT


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FIELD TRIP PROGRAM

Date Time Place

Monday, 24-Sep-2018 8:30 Danang University

Tuesday, 25-Sep-2018 8:00 Dung Quat refinery

Thursday, 27-Sep-2018

8:30 Nippon Paint company

14:00 Vietnam Petroleum Institute – Hanoi

Friday, 28-Sep-2018

8:30 B12 company - Quang Ninh

https://www.vpi.pvn.vn/


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ORAL PRESENTATION


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The observation of stereospecificity in Lewis-acid-catalyzed ring-opening polymerization (ROP)

of cacemic propylene oxide (rac-PO) without chiral additives dates back to the 50s.1 Remarkably, there are not any reports of ROP of epoxides with any dialkylmagnesium derivatives in the intervening >40 years in spite of the wide availability of these compounds and its reported potential as isospecific catalysts. With this in mind, we decided to reexamine this forgotten reaction. To our delight, by using di-n-butyl magnesium in the bulk ring opening polymerization of rac-PO, we produced highly isotactic poly(propylene oxide) with high number average molecular weight (Mn) in a controlled manner, even at high temperatures.2 Moreover, we also explored the bulk copolymerization of meso cyclohexene oxide (CHO) and CO2 with the same type of dialkylmagnesium catalysts. Interestingly, these simple achiral catalysts also exhibited excellent activity in the stereoselective low-pressure bulk copolymerization of meso-CHO and CO2. To the best of our knowledge, this is the first achiral catalyst system able to desymmetrize meso-CHO and catalyze its copolymerization with CO2.3

Figure 1. Synthesis of iso-enriched polyether homopolymers and copolymers catalyzed by achiral

alkylmagnesium compounds

References [1] a) Colclough, R. O.; Gee, G.; Higginson, W. C. E.; Jackson, J. B.; Litt, M. J. Polym. Sci. 1959, 34, 171. b) Osgan, M.; Price, C. C. J. Polym. Sci. 1959, 34, 153. c) Tsuruta, T.; Inoue, S.; Yokota, Y. Makromol. Chem. 1967, 103, 164. d) Vandenberg, E. J. J. Polym. Sci. 1960, 47, 486. [2] Ghosh, S. ; Lund, H. ; Jiao, H. ; and Mejía, E. Macromolecules, 2017, 50 1245 [3] Ghosh, S. ; Pahovnik, D. ; Kragl, U. ; and Mejía, E. Macromolecules, 2018 (accepted)

Isospecific Ring-Opening Polymerization and Copolymerization of Racemic Epoxides with Dialkylmagnesium Reagents

Swarup Ghosh, Esteban Mejía* Leibniz Institute for Catalysis (LIKAT). Albert-Einstein-Str. 29a, 18059 Rostock, Germany

[email protected]


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Abstract The presentation addresses the concept of sustainability from an environmental-economics

point of view and tries to apply economic insights to issues related to catalytic chemistry. I will distinguish between homogeneous pollutants such as CO2, arising from the combustion of fossil fuels and other chemical processes, and the highly heterogeneous and diverse substances released into the environment by the chemical industry and the users of its products, often with very uncertain consequences. Of course the latter are much more difficult to be addressed by environmental regulation than – for example – CO2 or NOx. I will discuss different methods of regulation with respect to their pros and cons. Moreover, I will address cost efficiency, i.e. the problem of achieving a given environmental target at minimum cost. Special emphasis will be placed on stock pollutants, which accumulate in the environment over time and have long-run future impacts affecting future generations' well-being. A final section will be devoted to "leap-frogging" strategies, which can be implemented by developing countries to skip the stage of pollution-intensive industrialisation and adopt modern environmentally friendly and sustainable technologies from the beginning.

Michael Rauscher* * University of Rostock

Sustainability, Environmental Economics, and Catalytic Chemistry


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Methylation is one of the most widely used reactions in fine chemical and pharmaceutical

industries [1]. Classical procedures for methylation often use toxic methyl halides or diazomethane as alkylating agents [2]. Recently, H-borrowing strategy for N-alkylation and α-alkylation has been developed using alcohols as green and non-toxic alkylating agents instead of using toxic alkyl halides [3]. Herein, [RuCp*Cl2]2 in the combination with a bidentate ligand (dpePhos) is reported as an efficient and high turnover catalyst for N-methylation of amines and α-methylation of ketones using methanol under neat conditions at 100-120oC following hydrogen borrowing strategy [4]. Interestingly, Naftifine and Ketoprofen drugs were successfully prepared via N-methylation and α-methylation methods in the employment of our Ru catalyst.

Scheme 1. Ru-catalyzed methylation of amines and carbonyl compounds using methanol

References [1] E. J. Barreiro, A. E. Kümmerle, C. A. M. Fraga, Chem. Rev. 2011, 111, 5215-5246. [2] J. March, M. B. Smith, Advanced Organic Chemistry, 6th. ed.; Wiley, 2007. [3] (a) G. Guillena, et al. Angew. Chem. Int. Ed. 2007, 46, 2358-2364. (b) G. E.; Dobereiner, R. H. Crabtree, Chem. Rev. 2010, 110, 681-703. (c) G. Guillena, et al. Chem. Rev. 2010, 110, 1611-1641. [4] (a) T. T. Dang, B. Ramalinegam, A. M. Seayad, ACS Catal. 2015, 5, 4082-4088. (b) T. T. Dang, A. M. Seayad, Adv. Synth. Catal. 2016, 358, 3373-3380.

Dang Thanh Tuan* * Faculty of Chemistry, Organic Chemistry Department. Hanoi University of Science, Vietnam

National University (VNU). 19 Le Thanh Tong street, Hanoi, Vietnam

Sustainable Ru-catalyzed Methylation of Amines and Carbonyl Compounds using Methanol as a Green Alkylating Reagent


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Dry reforming of methane (DRM) gathers recent concerns to convert natural gas and biogas

into syngas (mixture of CO and H2), which can be further processed in chemical syntheses (e.g., Fischer-Tropsch processes) [1]. There are German biogas [2] as well as natural gas sources in Vietnam (e.g., Blue Whale well [3]) with similar CO2 content (~30%) which could be processed by DRM. Ni-based catalysts are promising candidates for this reaction, but they tend to form Ni clusters and unreactive carbon on the surface leading to deactivation of the catalysts [1]. Previously, we developed low Ni content catalysts with Mg-Al mixed oxide supports that show high DRM performance with unity CH4/CO2 molar ratio [4]. In this study, promoted Ni catalysts were investigated for the DRM potential at a CH4/CO2 ratio = 2 which imitates mentioned bio-gas and natural gas sources. On the other side, this high CH4/CO2 ratio increases the coking rate [1], and by that, suited catalysts with carbon resistance can be recognized early and further applied in the industrial processing.

The UV-Vis DR spectra show intense signals in the UV region (200-350 nm) due to

charge transfer (CT) of O2-Ni2+ in octahedral NiO lattice. Compared to Ni/MgAlOx and La.Ni/MgAlOx, there are blue-shifts of CT band for Sc.Ni/MgAlOx and Gd.Ni/MgAlOx (Fig. 1), pointing out the stronger interaction of Ni species and support in two latter samples. TPD results show that promoting Ni catalysts results in higher basicity in the sequence Gd ~ La > Sc. DRM was evaluated with CH4/CO2 = 2 at high space velocity of 170 L/(gcat×h) and high reaction temperature (760 °C) (Figs. 3, 4). The unpromoted catalyst shows the fasted decline in conversion. On the other hand, Gd.Ni/MgAlOx maintains activity for at least 8 hours. This stability correlates to strong metal-support interaction and high basicity, which also results in the lowest carbon deposition (Fig. 2). The long-term stability on this most promising sample was tested under the same reaction conditions (Fig. 5). The carbon deposition was also negligible. The losses in conversions after 100 hours on stream are below 10% compared to the initial values.

References 1. A.N. Şener et al., Catal. Today 2018, 299, 289-302. 2. D. de Graaf et al., Biogas production in Germany 2010. 3. H.M. Truong et al., PetroVietnam Journal 2017 (1), 55-65. 4. Q.L.M. Ha et al., Catalysts. 2017, 7(5), 157-173.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Quan Luu Manh Ha*, Udo Armbruster*, Sebastian Wohlrab* * Leibniz Institute for Catalysis at the University of Rostock, Albert Einstein-Str. 29a, D-18059

Rostock

Promotion study on Ni catalysts for CH4 rich DRM


13

Abstract Carbon dioxide has drawn significant attention as the primary greenhouse gas contributors to

climate change. Carbon dioxide capture and storage (CCS) is one of the key options for mitigating CO2 emissions. However, the cost of CCS remains high at the present stage. Therefore, the innovative technologies to effectively reduce CCS costs are highly desirable. A wide range of approaches, including absorption (solvents), membranes, and adsorption, have been proposed for CO2 capture and separation. With many advantages comparing with other capture methods, CO2 capture using amine solid sorbents has been considered as one of the most promising techniques.

In this work, mesoporous silica materials with different pore volumes and fly ash were functionalized by wet impregnation method with a variety of amines including tetraethylenepentamine, several alkanolamines and heterocyclic amines for CO2 adsorption. Effects of (i) concentration and composition of amine blends, (ii) silica supports, (iii) solvents for impregnation, and (iv) adsorption temperature on the CO2 adsorption performance were investigated. The synergistic effects of blending amines on the CO2 uptake and the adsorption heat were also discussed in the present work. Those experimental results showed that as well as the pore volume of supports and adsorption temperature, molecular functional groups of blended amines do play important roles and have great effects on the CO2 adsorption capacity.

Dao Sy Duc

VNU University of Science, Vietnam National University-Hanoi 19 Le Thanh Tong Str., Hanoi, Vietnam

CO2 capture on amine-impregnated solid sorbents


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The increasing share of electrical power from wind and photovoltaics in present energy mix concepts demands new technologies for energy storage, because these resources are affected by spatial and temporal fluctuations [1,2]. The favored solution is the chemical storage of excess power by first generating H2 via electrolysis and methanation. The latter needs also abundant CO2 or CO [3]. The methanation is strongly exothermic, but needs high temperature and catalysts to activate CO2:

CO2 + 4 H2 CH4 + 2 H2O ΔH = -165.1 kJ/mol

Here, a commercial 18 wt% Ni/Al2O3 catalyst was used for CO2 methanation. In one approach, stainless steel tube reactors with (a) L = 276 mm, ID = 7.6 mm, V = 12.5 cm3, electrically heated and (b) L = 1000 mm, ID = 24.8 mm, V = 483 cm3, heated with heat transfer oil, were used. In parallel, the catalyst was supported on a ceramic monolith and a steel grid and tested in a tube reactor. The fresh and spent catalysts were characterized with XRD, BET and TEM. Optimum conditions with the small reactor (H2/CO2 = 4, 280 °C, 10 bar, 6000 h-1) led to a specific CH4

productivity of 1.1 l/(mlcath), which had to be up-scaled for commercial applicability. In the big

reactor, a value of 1.4 l/(mlcath) was achieved with 99.5% selectivity, but the catalyst temperature reached 450 °C. Improved heat distribution along the tube reactor and lowering of hot spot temperatures by 50 K were achieved by splitting the catalyst load into several beds of different height and quartz dilution. Long-term and stress tests under variable process conditions proved that the chosen catalyst was stable over 800 h.

Methanation of CO2 on 18Ni/Al2O3; Vcat= 30 ml, Vinert= 271 ml, Vtotal= 271.5 Nl/h; CO2/H2/N2 = 1.8:7.2:1; p = 10 bar; GHSV = 10000 h-1. Left: Temperature profiles. Middle: Scheme of one configuration of large tube reactor. Right: CO2 conversion and CH4 selectivity at different reaction temperatures.

By using 0.75 g of same catalyst ground and coated on a cordierite monolith, 23 ln/h CH4

were produced at a GHSV of 9000 h-1 (92% CO2 conversion, 99.9% selectivity). Using a steel grid as matrix at same conditions showed that heat transfer was improved and higher CO2 conversion was possible.

1 S. Ewald, F. Koschany, D. Schlereth, M. Wolf, O. Hinrichsen, Chemie in unserer Zeit, 49 (2015) 270-278. 2 S. Abelló, C. Berrueco & D. Montané, Fuel, 113 (2013) 598-609 3 M. Götz, J. Lefebvre, F. Mörs, A. M. Koch, F. Graf, S. Bajohr, R. Reimert & T. Kolb, Renewable Energy, 85 (2016)

1371-1390.

Hesham Mena, Daniel Türks, Michael Sebek, Elka Kraleva, Udo Armbruster, Sebastian Wohlrab Leibniz-Institut für Katalyse an der Universität Rostock

Methanation of CO2 on Ni/Al2O3 in Structured Reactors. A Scale-Up Study from Lab to Industry Application


15

Catalysts are the central engines of chemical transformation in the industry. Catalysts facilitate

the formation of the desired products by selectively opening up new, energetically favourable reaction routes. The understanding of catalyst has reached the reasonable status on conceptual level, but still quite far away from maturity. However, since the Nobel Prize in Chemistry 1998 was given to Walter Kohn "for his development of the density-functional theory" and John A. Pople "for his development of computational methods in quantum chemistry", the understanding about catalyst has gained significant improvements with the help of first principles modelling. Nowadays, molecular modelling has become an important tool to analyse the physicochemical properties of the catalysts at the molecular level and design novel materials for meeting our future energy needs in a sustainable manner. The ultimate goal for catalysis research is to design active, stable and selective catalysts. The typical scale to study catalytic reactions is the molecular scale - a scale which is very difficult to access experimentally, especially for complicated, multi-step reactions. First principles based molecular modelling on the other hand is best placed to investigate molecular level effects and can greatly help to guide and validate our chemical intuition on the molecular scale. This talk will illustrate how first principles based modelling is able to shed light into the mechanism and guide the design of heterogeneous catalysts with improved activity, selectivity and stability. Few examples will be presented including the design of core-shell electrocatalysts in oxygen reduction reaction and the promotional effect of Boron on transition metals (Ni, Cu) catalysts in tar elimination and methane conversion processes.

Quang Thang Trinh* * Cambridge Centre for Advanced Research and Education in Singapore (CARES),

Nanyang Technological University, Singapore (NTU), 1 Create Way, Singapore 138602 [email protected]

Computational Guided Design of Catalyst for Sustainable and Green Energy


16

The carbon dioxide reduction gains more importance due to the fact that the natural carbon

cycle is not able to convert the produced carbon dioxide completely. The aim is to store carbon dioxide or to use it properly as a reagent. Today two approaches for the reduction are of relevance, the electrochemical and photochemical reduction of carbon dioxide. In previous studies we investigated the photocatalytically active cyclopentadienone tricarbonyl iron complex, which has already been established in combination with an iridium photosensitizer, in regard of the electrocatalytical activity. [1] We were able to show that the catalyst is an electrochemically active reduction catalyst for carbon dioxide and to identify intermediates and propose a catalytic cycle. [2, 3]

In our recent work we studied a manganese diimine complex (Figure 1). In the photocatalytic investigations this complex has shown a very high TONCO and high selectivity in regard to the formation of CO. Furthermore it was proven that the catalyst is active under electrochemical conditions. It was possible to propose a catalytic cycle for the photocatalytic as well as the electrocatalytic CO2 reduction. Intermediates such as a dimer were identified as well as the products of the reaction, like carbon monoxide and bicarbonate. [4, 5, 6] In our studies we used IR spectroelectrochemistry (SEC) and in situ

IR spectroscopy to obtain a proper mechanistic insight. The spectroelectrochemical cell was built as suggested by Zavarine and Kubiak. [7]

References: [1] A. Rosas-Hernández, P. G. Alsabeh, E. Barsch, H. Junge, R. Ludwig, M. Beller, Chem.

Commun. 2016, 52, 8393 [2] A. Rosas-Hernández, H. Junge, M. Beller, M. Römelt, R. Francke, Catal. Sci. Technol. 2017, 7,

459 [3] E. Oberem, A. Rösel, A. Rosas-Hernández, T. Kull, S. Fischer, A. Spannenberg, H. Junge, M.

Beller, R. Ludwig, M. Roemelt, R. Francke, unpublished 2018 (will be submitted to Organometallics)

[4] C. Steinlechner, A. Rösel, E. Oberem, A. Päpcke, N. Rockstroh, F. Gloaguen, S. Lochbrunner, R. Ludwig, A. Spannenberg, H. Junge, R. Francke, M. Beller, submitted 2018

[5] Z. K. Lopez-Castillo, S. N. Aki, M. A. Stadtherr, J. F. Brennecke, Ind. Eng. Chem. Res. 2006, 45, 5351

[6] E. Garand, T. Wende, D. J. Goebbert, R. Bergmann, G. Meijer, D. M. Neumark, K. R. Asmis, J. Am. Chem. Soc. 2010, 132, 849

[7] I. S. Zavarine, C. P. Kubiak, J. Electroanal. Chem. 2001, 495, 106

Figure 6: [Mn(pyrox)(CO)3Br]

Elisabeth Oberem,*+ C. Steinlechner,+ A. Rösel,* H. Junge,+ M. Beller,+ R. Francke* and R.

Ludwig*+ * University of Rostock, Institute for Chemistry, Albert-Einstein-Straße 25, 18059 Rostock

+ Leibniz Institute for Catalysis, Albert-Einstein-Straße 29A, 18059 Rostock

Investigations of the Manganese Catalyzed CO2 Reduction probed by IR Spectroscopy


17

In situ EPR spectroscopy is a unique and sensitive technique for selective analysis of

paramagnetic as well as ferromagnetic species. Indeed, the appearance of the superhyperfine structure, which results from the coupling of an electron at the metal centre to other atoms with different nuclear spins, enables the identification of the nature of the metal ligands. Together with complementary techniques such as FTIR spectroscopy, EPR enables a comprehensive understanding of mechanisms.

Two selected catalytic systems will be discussed. First I would like to demonstrate our studies on mechanism of the homogeneous iron-iridium / iron-copper catalyzed water reduction systems.[1] By application of in situ EPR, activation as well as deactivation pathways of the iron catalyst as well as of the iridium catalyst were identified. The mechanism of the light-driven production of hydrogen by a heteroleptic CuPS and an iron WRC (Scheme 1) was investigated using several methods such as operando FTIR spectroscopy, UV/vis and in situ EPR spectroscopy as well as their combinations with spectroelectrochemical techniques.

The second example comprises a heterogeneous nickel-carbon nitride system which catalyses the water reduction [2]. Carbon nitrides (CN) revealed to be promising materials due to efficient charge separation, metal-free structure, as well as low-cost preparation. By EPR spectroscopy we could directly visualize light-driven charge separation inside the carbon nitride followed by transfer of electrons to the nickel sites from which they react with protons to form H2.

References [1] S. Fischer, D. Hollmann, S. Tschierlei, M. Karnahl, N. Rockstroh, E. Barsch, P. Schwarzbach,

S.-P. Luo, H. Junge, M. Beller, S. Lochbrunner, R. Ludwig, A. Brückner, ACS Catal. 2014, 4, 1845.

[2] A. Indra, A. Acharjya, P. W. Menezes, C. Merschjann, D. Hollmann, M. Schwarze, M. Aktas, A. Friedrich, S. Lochbrunner, A. Thomas, M. Driess, Angew. Chem. Int. Ed. 2017, 56, 1653-1657.

Keywords: EPR spectroscopy, copper, nickel.

Dr. Dirk Hollmann University of Rostock

EPR spectroscopy – a necessary tool for the investigation of Electron-Transfer-reactions

Fig.1 – Formation of Ni0 cluster during photocatalytic water reduction (nickel carbon nitride system)

Scheme 1. Reductive (red) and oxidative (blue) reaction pathway and the initial structures of the applied copper photosensitizer (CuPS 1) and water reduction catalyst (WRC).


18

Temperature-programmed methods are used to characterize solid materials based on

chemical interactions between gaseous reactants and solid substances. They comprise desorption (TPD), reduction (TPR) and oxidation (TPO) techniques. Thermal conductivity detector (TCD) and mass spectrometer (MS) are typical detectors for analyzing the gas phase. The TCD continuously measures the changes in the thermal conductivity in gaseous stream, while MS measures changes in gas composition. The data collected from these techniques can be interpreted qualitatively and quantitively. Typically, the measurements provide information on the temperature at which a change in physisorption/chemisorption of molecules on the solid occurs as well as on the number of molecules involved in such steps [1]. Knowing the total amounts of gas and solid, specific parameters of such systems can be determined, e. g., specific acidity.

With TPD, information about acidity or basicity of solid catalysts is provided. The probe gases used are NH3 and CO2 diluted in He. For the TPR H2 in Ar as probe gas is used to reduce metal oxide species in order to get information on redox activity of the compound. Fig. 1a presents TPR profiles of Co-Ni/x-SBA-15 where x represents promotors (Sc, Mg and La) added to SBA-15. These catalysts were tested in the dry reforming of methane (DRM). Generally, the incorporation of La and Sc into SBA-15 leads to poorer reducibility of the final catalysts, indicated by the shift of the reduction peaks to higher temperatures compared to Co-Ni/SBA-15, due to the solid interaction of the active metals Ni and Co with the support [2]. Basic centres play an important role in DRM for CO2 adsorption and its dissociation mechanism, as they reduce the carbon accumulation on the surface of the catalyst (via coke gasification). As shown in Fig. 1b, the TPD profiles at different temperatures reveal the strength of the basic centres. Addition of Sc or Mg increases the basicity, particularly illustrated by the peaks in the region between 200 and 400 °C, which in turn affects the catalytic activity. In this contribution, we will present theory and explanation of each method and its application in selected heterogenously catalysed reactions.

a)

100 200 300 400 500 600 700

339.0 °C

316.3 °C

314.9 °C

284.6 °CTC

D s

ign

al

(a.u

)

Temperature / °C

Co-Ni/SBA-15

Co-Ni/Sc-SBA-15

Co-Ni/La-SBA-15

Co-Ni/Mg-SBA-15

225 °C

254.6 °C

b) Figure 1: a) TPR and b) CO2-TPD profiles of Co-Ni/x-SBA-15 (x =0, Mg,La, Sc) catalysts [2].

References [1] J. A. Moulijn, P. W. N. M. van Leeuwen, R. A. van Santen, Stud. Surf. Sci. Catal. 79 (1993)

401. [2] A. S. Al-Fatesh, Y. Arafat, H. Atia, A. A. Ibrahim, Q. L. M. Ha, M. Schneider, M.-M. Pohl, A. H.

Fakeeha, J. CO2 Utilization 21 (2017) 395.

Hanan Atia1*, Udo Armbruster1, Sebastian Wohlrab1 1Leibniz Institute for Catalysis, Albert-Einstein-Strasse 29a, D-18059, Rostock, Germany

TPX methods for characterization of heterogeneous catalysts


19

Visible light-driven photocatalysis emerged as a strategic new tool for organic synthesis, as it

enables the discovery of unprecedented chemical reactivity and thereby leading to the development of novel methods for chemical bond formation. Consequently, photocatalysis has been applied to the synthesis of new functional target structures, the chemoselective derivatization of complex natural products as well as to the selective conversion of renewable feedstocks.

Our group has contributed to this area by developing new oxidative and reductive

photocatalytic transformations for C-C and C-O bond formation, enabling the synthesis of densely functionalized heterocyclic structures. This talk will give an overview of our work with organic and transition metalbased photocatalysts, with emphasis on key synthetic and mechanistic aspects, as well as the development of tandem catalytic protocols.

Quinones are potent stoichiometric ground-state oxidants in organic synthesis, and their use in

catalytic oxidations has only been developed in recent years. Upon electronic excitation, the oxidative power of quinones is further significantly enhanced, making inexpensive quinone dyes ideal organic photooxidants which readily promote photoelectron transfer, hydrogen abstraction and photooxygenation reactions. We developed quinone-catalyzed photoinduced amine oxidations and Csp3-H photooxygenations, leading to new procedures for the synthesis of polycyclic isoquinoline derivatives, substituted oxindoles and unusual indole alkaloid-derived spirocyclic 1,3-oxazines.[1-4]

Photocatalytic reduction of carbon halide bonds is a mild and environmentally benign method

to generate reactive carbon-centered radicals for C-C bond forming reactions. We have developed new free radical additions to indoles, which in contrast to previous methods allowed for the dearomatization of the indole nucleus. Valuable building blocks for alkaloid synthesis could be prepared, such as tricyclic benzindolizidines as well as highly functionalized hexahydrocarbazoles, which could be accessed via an unprecedented radical (4+2)-cyclization/1,4-addition cascade, which simultaneously generated three C-C and one C-H bonds, along with three contiguous stereogenic centers.[5-6]

References: [1] T. von Drathen, F. Hoffmann, M. Brasholz, Chem. Eur. J. 2018, DOI: 10.1002/

chem.201801882. [2] F. Rusch, L.-N. Unkel, D. Alpers, F. Hoffmann, M. Brasholz, Chem. Eur. J. 2015, 21, 8336-

8340. [3] S. Lerch, L.-N. Unkel, M. Brasholz, Angew. Chem. Int. Ed. 2014, 53, 6558-6562. [4] F. Rusch, J.-C. Schober, M. Brasholz, ChemCatChem 2016, 8, 2881-2884. [5] S. Mühmel, D. Alpers, F. Hoffmann, M. Brasholz, Chem. Eur. J. 2015, 21, 12308-12312. [6] D. Alpers, M. Gallhof, J. Witt, F. Hoffmann, M. Brasholz, Angew. Chem. Int. Ed. 2017, 56,

14021406.

Prof. Dr. Malte Brasholz* *University of Rostock, Institute of Chemistry – Organic Chemistry, Rostock, Germany

New Photocatalytic Reactions: Oxidative, Reductive and Tandem Transformations


20

This article reports the results of initial research on synthetic process of nitrogen

modified TiO2 nano material and coating on the rice husk ash by the sol-gel method. Nitrogen modified TiO2 nano material has anatase crystalline properties. The particle size has relative uniformity, about 25nm, and covers quite evenly on the surface of the husk ash. The specific surface area of the prepared material is 109.7 m2/g. The efficiency of NH4

+, NO3- and

NO2- removal from industrial wastewater was found to be promising, in natural lighting

conditions with the reaction time of 60 minutes, the concentrations of NH4+; NO3

- and NO2-

decreased from 20.00 mg/L to 0.053; 1.02 and 0.87 mg/L, respectively. The removal efficiency ranged from 77 to 97%. However, in dark conditions, the removal efficiency attained was very low.

Keywords: ammonium, nitrate, nitrite, hydrothermal method, rice husk ash, TiO2

nanomaterial

Dang Thi Ngoc Thuy1, Nguyen Hoang Nam1, , Do Khac Uan2, Nguyen Thi Ha3 1Department of Environment, Hanoi University of Mining and Geology, No. 18 Vien street,

Bac Tu Liem district, Hanoi 2School of Environmental Science and Technology, Ha Noi Polytechnic University, 1 Dai Co Viet,

Ha Noi 3Faculty of Environmental Science, VNU-University of Science, 334 Nguyen Trai, Ha Noi

Preparation of TiO2 nano material coating on rice husk ash and application for nitrohen compound removal from industrial

wastewater


21

Abstract Various tin oxides including the univalent and mixed valence tin oxides have been successfully

synthesized in precursor solution with some specific initial pH (pH of 2, 2.5, 3, and 4) using the facile one-step hydrothermal method in the well -controlled temperature of 150oC with soaking time of 16 hours. All the as-prepared tin oxides were characterized by X-Ray Diffratometer (XRD) and Scanning Electron Microscope (SEM) to study the phase transformation and surface morphology as a function of pH. Investigating the photoresponse and surface charge of the as-prepared tin oxide has also been investigated by UV-Vis spectrophotometer equipped with Diffuse Reflectance spectroscopy and Zeta analyzer. Those properties were important to study the photocatalytic performance of the as-prepared tin oxides examined by degrading the direct blue 71 (DB71) dye as the organic pollutant models. The result shows that 0.05 g mixture of SnO2 and Sn3O4 at pH 2 has the highest efficient photocatalytic degradation by completely degrading and mineralizing the DB71 dye solution in 120 min under UV-Vis light irradiation. Furthermore, the proposed photocatalytic mechanism was discussed. The photocatalytic performance has correlation to tin oxide compositions affected by the specific initial pH of the precursor solution. Initial pH plays a role to determine the formation pathways of tin oxide-based photocatalyst through the hydrothermal method. Therefore, the tin oxide-based photocatalyst was proven to be an promising process which offers energy-saving option for the future treatments in order to remove the pollutant in the environment.

Keywords: tin oxides, photodegradation, hydrothermal method, photocatalytic mechanism

Adri Hudaa, I Putu Mahendrab , Chanel Tri Handokoa, Reisya Ichwanic, Ha Minh Ngoc*d, and Fakhili Gulo*a

aEnvironmental Science Departement, Graduate Program, Universitas Sriwijaya, Palembang 30139, Indonesia bChemistry Departement, Faculty of Mathematics and Natural Science, University of Sumatera Utara, Medan 20155, Indonesia cMaterial Science and Engineering, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609, USA dKey Laboratory of Advanced Material for Green Growth, VNU University of Science, Vietnam National University, Hanoi 100000, Vietnam. Email: [email protected]

pH dependence in the formation of tin oxide based photocatalyst and its photocatalytic degradation of direct blue 71 (DB71)


22

Abstract In this work, activated carbon by two steps calcination at 800 ℃ and zinc oxide nano particles

loaded on activated carbon (ZnO/AC) has been successfully synthesized from rice husk for degradation of Janus Green B (JGB) under low UV light intensity. As-synthesized samples were characterized by SEM, XRD, and BET. Activated carbon (AC) had the high surface area (1062 m2/g) and pore volume (1.06 cm3/g), these value significantly decreased to 251 m2/g and 0.41 cm3/g, respectively, when ZnO loaded on surface of AC. The degradation of Janus Green B (JGB) on catalyst was carried out by batch test and reaction rates were determined by fitting the experiments profiles with pseudo-first-order model. The degradation efficiency and reaction rate of JGB on ZnO/AC, 99.49% and 0.083 min-1, were higher than those of AC, ZnO, and (Zinc Oxide/Zinc Hydroxide Carbonate/Activated Carbon), ZnO/ZHC/AC. The effects of initial conditions such as catalyst dosage, dye concentration, intial pH value, inorganic anions on photo-degradation of JGB were also investigated. Moreover, porous SiO2 material was also synthesized from rice husk by using a surfactant (CTAB) and ZnO/SiO2 was prepared by hydrothemal method for degarding the dyes in wastewater. It was observed that ZnO/SiO2 could degrade dyes not only under UV light also under solar light.

Keywords: Silica, Activated Carbon, Zinc Oxide, Rice husk, Photo-degradation

Nguyen Thi Van, Le Tien Dat, Hoang Thi Thu, Vu Anh Tuan* * School of Chemical Engineering, Hanoi University of Science and Technology, Hanoi, Vietnam

Preparation of porous materials ZnO/AC and ZnO/SiO2 from rice husk for photo-degradation of organic dyes in wastewater


23

Glycerol is the main by-product in the production of biodiesel from natural oils. Due to

increasing need of chemicals and fuels a sustainable use of natural renewable recourses is required. It allows to save petrol feedstocks, reduces energy consumption in industrial processes and it is environmental friendly. It is also a contribution to reduce climate change effects by reduction of the CO2 emission. The CO2 is cycled by photo synthesis in plants which provide fatty acid ester, i.e. vegetable or algae oil. The present project aims the synthesis of fuel additives obtained by the etherification of glycerol with short chain alcohols like t-butanol or ethanol. The corresponding glycerol ethers will be catalytic synthesized by using acid or supported acid catalysts, i.e. strongly acidic zeolite. Mostly, synthetic zeolites were used so far. However, the preparation of synthetic zeolites is less ecofriendly. It occurs at elevated temperature and consumes energy for heating. The preparation of synthetic zeolite also requires complex and hazardous chemicals as NaOH and organic templates. The use of natural occurring zeolites is, therefore, an interesting and environmental more benign alternative. This work deals with preparation, characterization and testing of a hierarchical porous clinoptilolite-based natural zeolite as a potential catalyst for the conversion of renewable glycerol feedstock to valuable fuel additives. The available natural zeolite clinoptilolite was ion exchanged with NH4NO3 solution at 80oC in 1h. The obtained solid was collected by filtration and calcined at different temperatures in order to obtain the acid form of the zeolite. The catalysts were characterized by TGA, BET, XRD, IR, SEM, TEM and acetalization reaction in order to study the textural, structural and acidic properties. The catalysts were tested in the acid catalyzed etherification of glycerol with t-butanol at elevated temperature with 7.5 wt % catalyst of glycerol weight. The reaction was performed with refluxing condition and in closed and stirred autoclaves under autogenous pressure (Parr 5500 and Parr 4848 autoclaves). Highest conversion ~70% of glycerol to MTBE (mono t-butyl glycerol ether) as main reaction product was achieved at 140oC in 4 hours with catalyst 400 0C calcination. In addition, the way to obtain the products from reaction more selectively was defined. The products were analyzed by GC MS, GC FID, with both DB wax 40/5-6-180/10-8-200/20 and HP5 GC-column. The H-form of natural zeolite shows high acidity and activity in the etherification reaction, which might be further enhanced by metal loading such as Fe, Zr, and Ti in following studies.

Axel Schulz 1, Hendrik Kosslick1, Riaz1, Do Trung Hieu1,2, Le Thanh Son2

1 Institute of Chemistry, University of Rostock, Germany 2 Faculty of Chemistry, VNU – Hanoi University of Science, Viet Nam

Acidic modifying of natural Zeolite to Etherification and Acetalization reaction in Green Chemistry


24

Supported Pt catalysts are usually used for the hydroisomerization, hydrocracking and

hydrogenation. The selectivity and product distribution depend on the acidity of the supports and hydrogenation activity of the active metal phase. SBA-15 is a highly ordered hexagonal mesostructure with thick uniform walls, good hydrothermal stability and large surface area. However, this pure siliceous has low acidity, its application on catalysis field is limited. The incoporation of aluminum and boron into the framework of SBA-15 to increase the acidity have been applied. Pt supported on B-modified SBA-15 have been used for hydrogenation of tetralin.

B-SBA-15 has been synthesized by direct and indirect synthesis method with Si:B ratio of 10:1. Wetness impregnation (WI) method is used to load platinum on B-SBA-15. The obtained support and catalyst was characterized by TPD-NH3 and FTIR-pyridin to investigate the influence of B on the acidity as well as the Bronsted and Lewis sites of the catalyst.

Keywords: B-SBA-15, TPD-NH3, FTIR-pyridin

Ngo Thi Thanh Hien, Le Van Tuyen, Le Van Tuan, Pham Thanh Huyen School of Chemical Engineering, Hanoi University of Science and Technology

Influence of boron on the bronsted and lewis acid sites of sba-15 and pt/sba-15 catalyst for the hydrogenation of tetralin


25

A series of hierarchical ZSM-5 materials including nanosized ZSM-5 (Nano-ZSM-5), nanosized

ZSM-5/SBA-15 composite (Com-ZSM-5) and mesoporous ZSM-5 (Meso-ZSM-5) were prepared and their physicochemical properties were thoroughly characterized by XRD, SEM, TEM, N2-sorption, AAS, ICP-AES, NH3-TPD and FTIR of adsorbed pyridine. It was found that all synthesized hierarchical ZSM-5 materials exhibit the preservation of intrinsic, strong Brønsted acidity of ZSM-5 along with the enlarged external/mesoporous surface. However, the development of mesoporosity by reducing the crystal size of ZSM-5 appears limited (Smeso = 134 m2/g). Remarkably, the introduction of either intercrystalline mesopores by dispersion of Nano-ZSM-5 in the mesoporous SBA-15 analog matrix (Com-ZSM-5) or intracrystalline mesopores by the alkaline-acid treatments (Meso-ZSM-5) significantly improves the external/mesoporous surface (Smeso = 233-297 m2/g).

Vu Xuan Hoan 1, *, Dang Thanh Tung 1, Vu Duy Hung 2,3, Tran Thi Nhu Mai 3

1 Vietnam Petroleum Institute, 167 Trung Kinh, Yen Hoa, Cau Giay, Hanoi 2 Binh Son Refining and Petrochemical Company, 208 Hung Vuong, Tran Phu, Quang Ngai

3Hanoi University of Science, 344 Nguyen Trai, Thanh Xuan, Hanoi *Email: [email protected]

Preparation and characterization of hierarchical ZSM-5 materials for enhanced cracking of 1, 3, 5 - triisopropylbenzene at low

temperature

mailto:[email protected]


26

Aim of the presentation is the introduction of the joint project SUVALIG (project partners are

also participants of the RoHan project). Overall goal of the project is the development of a sustainable circular biorefinery concept for

rural communities in Vietnam with the focus of cascading use and valorization of lignocellulose waste in form of novel bio-based products and sustainable utilization pathways. The idea behind the project is the development of an integrated system that allows localized production of energy and an assorted amount of bio-products, such as biofuels, fertilizers, as well as higher value products. At the end of the project should be a pilot biorefinery concept, valorizing the typically available biomass in rural communities in Vietnam which is transferable to other regions within the country and beyond. Investigation in biomass, pre-treatment and final treatment processes and technologies will be made available to the worldwide scientific communities and plant manufacturers by publications and conferences. The new knowledge will referred to students and junior scientist of the partner universities and build the basis for future research and technology transfer into the practice.

The research is related to the field of catalysis by development of bio-based catalyzer materials. The SDG are part of the project aims: hydric and terrestrial resources should be sustainable managed, sustainable and affordable energy sources should be assured and the environmental impact of human activities reduced.

Figure: Concept idea of the project SUVALIG

Dr. Andrea Schüch,* *Scientific Assistant at Professorship Waste and Resource Management at the Agricultural and

Environmental Faculty of the University of Rostock

Sustainable biorefinery concept focusing valorization and cascading of Vietnamese lignocellulose waste


27

HMF is a platform chemical, from which many other valuable chemicals and biofuels (for

replacement of fossil fuel) are synthesized. Synthesis of HMF from a renewable, abundant biomass material such as waste wood chips contribute to enhance the value of using of this biomass as well would be applied for other biomass such as rice straw, corn stalks, bagasse, etc. The process requires a reusable, recyclable solid catalyst that is synthesized from biomass material.

In this research, carbon base solid acid catalyst was prepared from waste wood chip by calcination of raw material followed by sulfonation process. The solid acid was characterized by XRD, TPD-NH3, FT-IR, BET. Results showed that the catalyst has amorphous structure with surface area more than 700m2/g, acid density around 3mmol/g.

The solid acid was applied for 5HMF synthesis from glucose, yield of glulose conversion more than 50% with 5-HMF selectivity around 20%.

Nguyen Trung Thanh1, Esteban Mejía2, Le Quang Dien1

1Hanoi University of Science and Technology; 2Leibniz Institute for Catalysis

Applied carbon-based solid acid catalyst from waste wood apply for 5-HMF synthesis


28

In recent years, many researchers focused on the development of green technologies and

products due to the limitation of fossil resources and with the goal of a sustainable future. For this reason, biomass-derived chemicals are receiving increasing attention. In particular, -valerolactone (GVL), which is recognized as a green solvent, a potential fuel additive and a reactant, has been proposed as the so-called platform chemical. It can easily be obtained from biomass-derived levulinic acid [1]. One promising application is the conversion of GVL into methyl pentenoates (MP) [2-3]. For this trans-esterification reaction, ring opening and subsequent dehydration of GVL is a crucial step to form an isomeric mixture of pentenoates. It should be noted that all MP isomers can be converted into adipic acid, but only the terminally unsaturated methyl 4-pentenoate is suitable for its conversion into ε-caprolactam. Since adipic acid and ε-caprolactam are monomers for the polyamides nylon and nylon-6 (perlon), respectively, this reaction pathway thus opens the possibility to produce these two most important polyamides based on renewable resources. The primary objective of this study is the selective conversion of GVL with methanol to methyl pentenoates (Scheme 1) using solid acid catalysts in a continuous gas phase process. Another objective is to maximize MP selectivity and productivity with a special focus on enhancing the selectivity of the terminally unsaturated methyl 4-pentenoate.

Results revealed that the ZrO2 / SiO2 catalytic system was found to be the most suitable for producing MPs from GVL in one step. Moreover, the effect of different reaction parameters such as the metal loading on the support,

the molar ratio of GVL : MeOH, the residence time etc. were also investigated. A GVL conversion of 93 % was achieved at a total MP selectivity of 99 %, albeit with a selectivity to M4P of only 30 %. After optimisation of reaction conditions, a long term experiment was performed and observed a stable catalyst activity for one week with significantly high selectivity (80 %) to M4P at 64 % GVL conversion. It is worth mentioning that a space-time-yield of 2800 gMP/kgCat/h, of which 1700 gM4P/kgCat/h was successfully achieved under suitable reaction conditions. To our knowledge, this is the best result reported so far. On the whole, it can be stated that the catalyst composition, feed composition and the reaction temperature are the key to tune the catalytic properties and in particular the product distribution of the reaction.

References: [1] J. G. de Vries, Chem. Rec. 16 (2016) 2787 [2] R. Fischer, U. Vagi, Patent US 4 740 613 (1988), BASF [3] L. E. Manzer, Patent WO 2004/ 007 421, Du Pont

A. Marckwordt, H. Amani, V.N. Kalevaru, S. Wohlrab, P. Kamer and J.G. de Vries Leibniz Institute for Catalysis, 18059 Rostock, Germany

Toward bio-based polyamides – methyl pentenoate production in a continuous gas phase process

Scheme 1. Conversion of bio-based GVL to MPs


29

Oxidative esterification is nowadays an important atom-economical reaction in organic

chemistry that allows the synthesis of esters starting from an alcohol and an aldehyde.1 Today 5-

Hydroxymethylfurural (HMF) is on the spotlight because it is an important derivative in biomass treatment, specifically lignocellulose, and especially because the furanic derivatives of HMF (e.g. 2,5-

furandicarboxylic acid) are being used as monomers for polymer production.2 In that sense, the

oxidative esterification of HMF represents a pathway of valorization of this molecule by producing

new starting monomers, since storage of HMF is not desired given its inherit reactivity.3 Herein, we

report the oxidative esterification of HMF with 1,6-hexanediol, catalyzed by 1,4-dimethyl-1,2,4-triazolium iodide (A) and Manganese(IV) Oxide. Both catalyst works in synergy, being the role of Manganese(IV) Oxide to act as an oxidation catalyst of the so-called Breslow intermediate formed between the HMF and the carbene. These reactions are performed under 1 bar of oxygen which acts as the terminal oxidant.

Figure 1. Carbene/Manganese catalyzed oxidative esterification of HMF.

Carbene/Manganese catalyzed oxidative esterification of 5-Hydroxymethylfurural

Abel D. Salazar-La Rosa*, Tran Thi Thuy° and Esteban Mejia*. *Leibniz Institute for Catalysis, Albert-Einstein-Straße 29a, 18059 Rostock,

Germany °Hanoi University of Science and Technology, 1 Dai Co Viet street, Hanoi, Vietnam


30

Phenazine radical cations (PRCs) were found to be efficient and highly selective metal-free

catalysts for the oxidative homo- and cross coupling of a variety of amines. In order to investigate the electronic substituent-effect on both the radical stability and catalytic activity, different PRC catalysts were synthesized by the reduction of phenazine with sodium dithionite. The reduction product was then functionalized by a Buchwald-Hartwig coupling reaction to obtain products with high yields; these were characterized by NMR spectroscopy. Upon oxidation, the PRCs were investigated by EPR, UV-vis, and fluorescence spectroscopy as well as by cyclovoltammetric measurements; furthermore, it was possible to characterize them by single crystal refraction. All obtained EPR spectra agree with simulated spectra of the PRCs.

It was found that all synthesized phenazines were catalytically active; however, the highest reaction rates and the best selectivity was achieved using a 5,10-Dihydro-5,10-dimethylphenazine radical cation. By using this catalyst in 1 mol% loading, a variety of different amines were oxidized in neat conditions with atmospheric oxygen pressure to yield homo-coupled aliphatic and aromatic imine dimers with yields up to 99 % and selectivity up to 98 %. Furthermore, cross-coupling reactions were performed under these conditions with yields up to 78 % and moderate selectivity up to 51 %. Kinetic studies indicated that the reaction rate is nearly independent of the electronic nature of the substituents, since all the obtained kinetic constants are in a narrow area of 0.66-0.75 molL-1 s-1 and all reactions are of first order kinetics. This suggests that the reaction might not be limited by the oxidation of the amine to an intermediate catalyzed by the phenazine radical cation, but by the diffusion of oxygen into the reaction mixture. Therefore, the oxygen pressure was increased to 10 bar in the cross-coupling reaction, increasing both the yield (up to 99 %) and the selectivity (up to 90 %) of the desired, cross-coupled product.

In order to explore the origin of the exquisite activity of a/the PRCas a catalyst, the amine oxidation reaction was investigated using UV-vis, fluorescence and EPR spectroscopy. A strong fluorescence emission of the non-radical phenazine in the range of 450-600 nm was measured, which disappeared almost completely upon oxidation to the PRC. This fluorescence quenching was undone by adding benzylamine to the solution. To further confirm the nature of the phenazine redox ability to transfer the charge from the pyrazine core to benzylamine, the process was trackedby UV-VIS spectroscopy and a significant absorption band changing in the range from 500-750 nm was observed. Also, the EPR spectroscopy suggested, by a significant signal changing upon addition of benzyl amine, that a single electron transfer from the amine to the PRC takes place, which is assisted by the formation of active oxygen species. Therefore, we were able to propose a reaction mechanism and it was furthermore possible to detect all predicted intermediates either by NMR or GC/MS.

The catalytic system presented in this work follows the trend of replacement of metal-based catalysts in the chemical industry as there is a need of novel, more environmentally friendly catalysts for chemical transformations. Since no solvents, harmful reagents or metals were used for the herein presented, highly efficient oxidative homo and cross coupling of amines, this process employing a PRC as a catalyst, could potentially replace commonly known metal-based processes in the future.

Felix Unglaube,* Rok Brisar,*Dirk Hollmann,‘‘ Esteban Mejía* *Leibniz-Institut für Katalyse e.V. an der Universität Rostock

‘‘Universität Rostock

Phenazine Radical Cations as Metal-Free Catalysts for Aerobic Oxidations


31

A set of CuxMg0.7-xAl0.3(OH)2(CO3)0.15.mH2O hydrotalcite-like compounds were synthesized by

the co-precipitation technique at a certain pH. The synthesized samples have been characterized by some physical means of XRD, FT-IR, TEM, EDS and BET prior to use as catalyst for the liquid oxidation of styrene with aqueous tert-butyl hydrogen peroxide (TBHP) oxidant. The synthesized samples show good hydrotalcite structure and with the presence of Cu(II) ions in layered Mg-Al hydroxides. Under similar reaction conditions, MgCuAl-CO3 layered double hydroxide catalysts exhibited better activity and higher selectivity towards styrene oxide (75% selectivity at 73% styrene conversion) as compared with the MgAl-CO3, CuO/MgAl-CO3, and mixed oxide of MgCuAl-O.

Keywords: Mg-Cu-Al; hydrotalcite; oxidation; styrene; styerene oxide; benzaldehyde.

Le Thi Kim Huyena,b, Nguyen Tien Thaoa aFaculty of Chemistry, Vietnam National University Hanoi

bMien Trung Industry and Trade College

Liquid Oxidation of styrene Mg-Cu-Al Layered Double Hydroxide Catalysts


32

The oxidation of unreactive C–H bonds is of great interest in current research, granting

direct access to a broad spectrum of value-added products. To date, the majority of catalytic methods for C–H oxidation are based on transition metal catalysts. However, non-metallic alternatives like peracids and dioxiranes are available too. Problematic in this regard is the necessity of superstoichiometric quantitites of the oxidant, along with an intrinsic elevated hazard potential of the oxidizing agents. Because of high substrate specifity and high selectivity enzymatic systems were investigated, but often require specialized techniques and handling while providing low space-time yields.

The set objective of our research is the development of a general methodology for the direct oxygenation of C–H bonds by means of photoinduced oxygen atom transfer. Many heteroarene N-oxides are bench stable, nontoxic and can in combination with a suitable light source be used in transferoxygenation reactions. [1],[2]

Pyrimido[5,4-g]pteridine N-oxides are particularly interesting in this regard as they serve both as organo photocatalyst and transferoxygenation reagent. Subject of this contribution is the synthesis of pyrimido[5,4-g]pteridine 5-oxides, their photophysical properties and application in transferoxygenation reactions.

References: [1] a) D. M. Jerina, B. Witkop, C. L. McIntosh, O. L. Chapman, J. Am. Chem. Soc. 1974, 96, 5578–

5580; b) A. Petrosyan, R. Hauptmann, J. Pospech, Eur. J. Org. Chem. 2018, DOI:

10.1002/ejoc.201800152; c) Y. Maki, M. Sako, Syn. Org. Chem. Jpn. 1994, 2, 149‒160. [2] a) C. K. Prier, D. A. Rankic, D. W. C. MacMillan, Chem. Rev. 2013, 113, 5322–5363; b) K. Teegardin, J. I. Day, J. Chan, J. Weaver, Org. Process Res. Dev. 2016, 20, 1156–1163.

Dr. Jola Pospech,* * Leibniz-Institut für Katalyse e.V., Albert-Einstein-Str. 29a, 18059 Rostock, Germany.

A light touch: Photo-mediated Functionalization of Organic Molecules


33

Synthesis of N-dopped TiO2 nanotube material towards

application for VOC s treatment

Nguyen Hai Minh, Vu Ha Giang, Pham Van Phong, Hoang Van Ha, Le Thi Hoang Oanh VNU University of Science, 334 Nguyen Trai, Thanh Xuan, Hanoi, Vietnam

TiO2 is one of the most studied compounds in material science. It is used in paint, food, medicament,

solar cell, photocatalysis, etc. TiO2 is commonly used in the form of particles, however different nanostructures have received attention recently. In this study, N-doped TiO2 nanotube material was synthesized from commercial TiO2 by hydrothermal synthesis in concentrated NaOH solution (10M) with high temperature (100-180oC) and pressure conditions. Its morphology, crysralline phase and composition were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X ray diffraction (XRD), Time-of-Flight Secondary Ion Mass Spectrometry (TOF- SIMS) and ultraviolet-visible spectrophotometry (UV-Vis). The results showed that nanotubes have high specific surface area with 10-12 nm diameter and about 150 nm length. The photocatalytic activity of this material (0.25 g) was evaluated in terms of photodegradation of ethanol (315 mg/m3) under ultraviolet light in 2 hours. It showed that ethanol treatment efficiency of nanotubes (55%) is higher than nanoparticles (40%) and the activity is enhanced when there is nitrogen doping (85%). Further development of TiO2 nanotube material should be investigated towards treatment of VOCs.

Keywords. Titan dioxit, nanotubes, VOCs, hydrothermal, photocatalysis. Corresponding author: Hoang Van Ha Faculty of Chemistry, VNU University of Science 19 Le Thanh Tong, Hoan Kiem, Hanoi, Vietnam. E-mail: [email protected]



34

Abstract Nano composites based on CeO2 and graphene oxide were synthesized using Ce(NO3)3.6H2O

and graphite as precursors. The structure and surface characteristics of as-synthesized materials were studied with the aid of modern physico-chemical techniques such as SEM, EDX, XRD, UV-Vis, FT-IR, and BET. Influencing factors such as reaction time, pH of solution, initial concentration of pollutants, and catalyst load on photocatalytic degradation of Rhodamine B (RhB) in aqueous solutions by CeO2/GO catalyst were performed at room temperature and atmospheric pressure. The results showed that CeO2 existed in spherical form with an average diameter of 15.9 nm and these nanoparticles formed agglomerates, having larger diameters. CeO2 nanoparticles were well dispersed on the surface of GO and between GO sheets. The light absorption of CeO2/GO-based nanocomposite was significantly improved in the visible light region, implying practical application of CeO2/GO photocatalytic system. The results on photodegradation of RhB indicated that RhB was degraded the most in neutral and week acidic or basic solutions due to the surface characteristics of CeO2/GO, properties of RhB in solutions such as the formation of dimer, trimer that are more cumbersome, the protonation levels of RhB in solutions, and the electrostatic attraction between two π electrons of GO and RhB. The optimal conditions for photo-degradation of RhB were as follows: week acidic to neutral to week basic solutions at 300 min of reaction time with an initial RhB concentration of 20ppm, and 500 mg/L catalyst.

Keywords: Cerium oxide, graphene oxide, composite, photocatalysis, Rhodamine B Acknowledgement: The authors would like to thank ROHAN Catalysis project for the utilization

of experimental instruments.

TRAN Dinh Trinh*, HA Thi Hoai, DANG Viet Cuong VNU-Key Lab. of Advanced Materials for Green Growth, Faculty of Chemistry, VNU University of

Science, 19 Le Thanh Tong, Hoan Kiem, Hanoi, Vietnam

Enhanced photocatalytic degradation of Rhodamine B in aqueous solutions using CeO2/GO photocatalysts


35

TiO2 has been widely investigated for application as as a photocatalyst in many years

thanks to its advantages of low cost, nontoxicity, availability and structural stability. However, due to the wide band gap in TiO2 structure, the photocatalysis over TiO2 has been only active under UV light. Therefore, many research focused on improving of its catalytic activity in the visible light to widen its photocatalysis application in the reallity at high economic effects. Noble metal deposition is one of those methods, which has been widely applied to enhance the photocatalytic activity of TiO2.

In this research, Ag/TiO2 was synthesized by chemical deposition using silver nitrate, cetyltrimethyl ammonium bromide, sodium borohydride and the commercial TiO2 P25 powder. The synthesized catalysts were characterized by XRD, SEM, EDS and UV-Vis. The photocatalytic activity of synthesized catalyst was tested for Cr(VI) destruction performed in a batch reactor under visible light irradiation. Nano particles of silver were found deposited on TiO2 surface and resulted in the plasmonic effect, which support for the Ag/TiO2 catalyst working active under the visible light. Further improvement of the photocatalytic reduction of Cr(VI) was examined by the presence of phenol and citric acid in the reaction system. Effects of Ag mole ratio, phenol/Cr(VI) ratio, pH, reaction duration, catalyst amount on reduction eficiency were investigated. The optimum conditions for photocatalytic reduction of Cr(VI) to Cr(III) were calculated using MODDE5 software. Under the visible light and optimum reaction conditions, 99,6% Cr(VI) was converted in the presence of Ag/TiO2 photocatalyst.

Ngo Sy Thuy, Tran Thi Kieu Trinh, Nguyen Hong Lien Hanoi University of Science and Technology

Synthesis and application of Ag/ TiO2 for the photocatalytic treatment of Cr(VI) in water under visible light


36

Selective catalytic reduction (SCR) of nitrogen oxides by ammonia over V2O5-WO3/TiO2

catalysts is one of the most popular techniques to control NOx emission from combustion processes which, however, operates only in a rather high and narrow temperature range of 300-500 °C. The temperature of other NOx sources such as diesel or lean-burn gasoline engines is much lower. Therefore, development and optimization of catalysts being highly active and selective for NH3-SCR of NOx already at temperatures well below 300 °C is highly desirable [1]. Among a variety of catalysts tested for this purpose, those containing manganese belong to the most active ones [1 ,2]. Unfortunately, most of these materials have major drawbacks. They form N2O as a serious greenhouse gas, especially with rising reaction temperature, and they are poorly resistant to other exhaust gas components such as SO2 and H2O [3]. To date, significant efforts have been done to solve these limitations. One promising approach is to mix or dope MnOx with other oxides. Recently, we have developed a series of VOx/Ce1-xTixO2 catalysts in which already the best binary oxide support

Ce0.5Ti0.5O2 achieved high NO and NH3 conversion of 80 % at 200 °C in the absence of vanadium. Deposition of vanadia on the surface of this support boosted NH3-SCR activity tremendously, reaching 100 % NO conversion and 100 % N2 selectivity even well below 200 °C at a gas hourly space velocity (GHSV) of 70,000 h-1 which outperformed the state of the art significantly [4].

In the present work, we aim to improve the catalytic performance of the binary oxide Ce0.5Ti0.5O2 even more by combining it with MnOx for low-temperature NH3-SCR of NO. Incorporation of Mn into Ce0.5Ti0.5O2 increased the NO removal efficiency, reaching both NO and NH3 conversions above 85 % between 175 to 300 °C at remarkably high N2 selectivities of ≥ 95 %. Deposition of vanadia on the Ce0.5Ti0.5-

xMnxO2- supports enhanced N2 selectivity,

reaching 98 % in the whole temperature range for Mn percentages of ≤ 0.1 (Fig. 1). The interaction of bare supports and catalysts with individual feed components (NH3, NO+O2) and total NH3-SCR feed was investigated by operando EPR and DRIFTS to elucidate the structure-reactivity relationships of catalysts.

References [1] J. Li, H. Chang, L. Ma, J. Hao, R.T. Yang, Catal. Today, 2011, 175, 147-156. [2] S. Zhang, B. Zhang, B. Liu, S. Sun, RSC Adv. 7 (2017) 26226-26242. [3] C. Liu, J.W. Shi, C. Gao, C. Niu, Appl. Catal., A 522 (2016) 54-69. [4] T.H. Vuong, J. Radnik, J. Rabeah, U. Bentrup, M. Schneider, H. Atia, U. Armbruster, W.

Grünert, A. Brückner, ACS Catal. (2017) 1693-1705.

Thanh Huyen Vuong, Jabor Rabeah, Ursula Bentrup, Matthias Schneider, Hanan Atia, Udo Armbruster, and Angelika Brückner *

Leibniz Institute for Catalysis at the University of Rostock, Albert-Einstein-Str. 29a, 18059 Rostock, Germany

Synergistic effect of VOx and MnOx surface species for improved

performance of V2O5/Ce0.5Ti0.5-xMnxO2- catalysts in low-temperature NH3-SCR of NO

Fig. 1. Catalytic behaviour of Ce0.5

Ti0.5

Mn0.5-x

O2-

supports and V/Ce0.5

Ti0.5

Mn0.5-x

O2-

catalysts


37

8-membered ring (8MR) zeolites have been recognized to have excellent activity for the

selective catalytic reduction (SCR) of NOx. The catalysts have also shown improved hydrothermal stability, hydrocarbon tolerance, and enhanced N2 selectivity towards N2O as compared to 10 MR and 12 MR zeolite catalysts. SSZ-39 (AEI), SSZ-16 (AFX), and SSZ-13 (CHA) zeolites having low framework density (15.1 T atoms per 1000 Å3) are silicoluminate with a three-directional pore systems with D6R in its structure (Fig. 1). CHA has one large ellipsoidal cavity (7 Å × 11 Å), differing from AEI in that AEI has a pear-shaped cage, and AFX contains one large aft-cage (7 Å × 17 Å) and a smaller gme-cage (7 Å × 6 Å). Herein, we investigated in catalytic performance of Cu-loaded CHA, AEI, and AFX zeolites with different Si/Al ratios in the selective catalytic reduction (SCR) of NOx with NH3. CHA, AEI zeolites with various Si/Al ratios have shown similar NOx conversions over a wide range of temperature (150 oC - 450 oC), and lower N2O selectivity in the lower silica CHA catalysts. High silica AFX (Si/Al=15) underperformed compared to other catalysts indicating a difference in aluminum distribution, thus an active site distribution difference in this high silica material.

Figure. CHA (left), AEI (middle), and AFX (right) structures. Si/Al atoms are dark blue spheres

and oxygen atoms omitted for clarity References 1. A. M. Beale, F. Gao, I. Lezcano-Gonzalez, C. H. F. Peden and J. Szanyi, Chemical Society

Reviews, 2015, 44, 7371-7405. 2. H.-Y. Chen, Z. Wei, M. Kollar, F. Gao, Y. Wang, J. Szanyi and C. H. F. Peden, Journal of

Catalysis, 2015, 329, 490-498. 3. F. Gao, N. M. Washton, Y. Wang, M. Kollár, J. Szanyi and C. H. F. Peden, Journal of Catalysis,

2015, 331, 25-38. 4. T. D. Pham, M. R. Hudson, C. M. Brown and R. F. Lobo, ChemSusChem, 2014, 7, 3031-3038.

Trong Dinh Pham*, Son Thanh Le* *Department of Petrochemistry, Faculty of Chemistry, VNU University of Science, Hanoi, Vietnam

Small Pore Zeolite Catalysts for the Selective Catalytic Reduction of NOx


38

By application of catalysts the rate of chemical processes can be enhanced and hence a more

efficient and cheap production can be achieved. Optimization of known catalysts and reaction routes as well as development of completely new catalysts is an ongoing task. Tailoring catalytic properties of available materials by implementation of different supports, by alloying with other materials or by doping with non-metallic compounds offers a wide field of potential solutions.

Understanding the most simple reactions and processes is a significant step to understanding more complex systems. Here, the oxidation of CO has to be mentioned. CO is one of the most problematic waste products of the combustion of fossil fuels. Thus, removal of CO by oxidation to CO2 is a crucially significant task. Moreover, CO and CO2 are well known reactants and intermediates in energy conversion processes. Due to its simplicity, oxidation and adsorption of CO has been a model system for investigations of supported noble metal catalysts for several decades. Moreover, CO is a favorable candidate for investigations on the nature of heterogeneous catalysts. When adsorbed on a metal, the CO vibration frequency is highly sensitive to external influences. Hence, information about contributions of adsorbates, dopants and other surface species can be obtained via vibrational frequency changes of adsorbed CO monitored by IR spectroscopy.

Chemical reactions that proceed in presence of water show a high degree of complexity. Using the knowledge on CO adsorption research in the gas phase, one can try to understand the role of water in liquid-phase reactions, too. Gaining insights and understanding processes which involve simple model reactions like CO adsorption and oxidation might provide the link to understanding more complex reactions on metals in the liquid phase. ATR-IR spectroscopy overcomes difficulties associated with high IR absorption of water and allows studies on heterogeneous catalysts in the aqueous phase.

The aim of this work was to investigate CO adsorption on Pd nanoparticles supported on TiO2. On the one hand, the influence of water on the CO adsorption was studied. On the other hand, the effect of pre-treatment of TiO2 with different gases on the final catalyst was explored.

Supported catalysts with 5wt%, 1wt% and 0.5wt% of Pd were synthesized with TiO2 pre-treated with H2, He and NH3. Formation of PdHx species was shown during reduction in H2 atmosphere. A subsequent post-treatment with He at 573 K reduced the amount of PdHx successfully. CO adsorption experiments were conducted in the gas and in the liquid phase. DRIFTS experiments were performed with 1wt% samples. The nitrogen-doped support favored deposition of very small and highly dispersed particles. Linear adsorption of CO was found to be favored on 1% Pd/TiO2-NH3. The linear-to-bridged ratio of adsorbed CO on the catalyst with untreated support was inversed for the nitrogen-doped catalyst. Pre-treatment of the support with He does not influence the size or dispersion of the metal deposition.

During ATR-IR spectroscopy measurements of CO absorption in water a red shift was detected for all absorption bands, which was attributed to changes in the potential of the metal particles due to co-adsorbed water. Pre-treatment of the catalyst was found not to affect the adsorption behavior of CO in water. Catalyst samples with the same Pd loading but different pretreatments showed very similar adsorption behavior. This might also mean that very small particles, which feature high catalytic activity in the gas-phase, are not available for the catalysis in the liquid phase. This would drastically decrease the catalytic activity of the investigated catalyst in water, making it potentially unsuitable for an application in water.

Investigation of liquid-phase CO adsorption on Pd nanoparticles supported on doped TiO2

M.Sc. Pawel Naliwajko, research group Prof. J. Strunk, LIKAT


39

The presentation consists of two parts. Part one will give some basics about physisorption of gases on solid surfaces used for BET measurements. It includes informations about history of the method, sample preparation, the measurement and about calculations of surface, pore volume and pore size distribution. Part two contains some recipes for preparation of micro- and mesoporous materials, examples are zeolite Y, SAPO-34 and MCM-22 for microporous materials and alumina, SBA-15 and modified silica gels for mesoporous supports. The influence of varying some parameters of the synthesis will be show with respect to changes in the BET surface and pore diameter of the samples.

Reinhard Eckelt LIKAT Rostock

Basics of BET Measurement and some Examples for Preparation of micro- and mesoporous Materials


40

Graft copolymerization of styrene onto deproteinized natural rubber (DPNR) using tert-butyl

hydroperoxide (TBHPO) and tetraethylene pentamine (TEPA) as redox initiator have been investigated. The effects of initiator and monomer concentration on conversion and grafting efficiency were studied. The dynamic mechanical and thermal properties of the graft copolymer were investigated over the wide range of temperatures. It is shown that a high value of storage modulus for the graft copolymer, which was about 25 times as high as that of DPNR, was achieved. The graft copolymer (DPNR-graft-PS) showed the outstanding tensile strength and stable thermal properties. It was found that the tensile strength depends on the grafted polystyrene, meanwhile the dynamic mechanical properties of the modification of DPNR meaningfully improved with the increasing both homopolystyrene and grafted polystyrene compared to DPNR. The dynamic mechanical properties of graft-copolymer over a large time scale were studied by constructing the master curves. The value of bT has been used to prove the energetic and entropic elasticity of the graft-copolymer. Morphology observation by transmission electron micrograph (TEM) revealed that the core-shell arrangement of the DPNR-graft-PS with about 30 nm in thickness of polystyrene nano-layer was achieved.

Tran Anh Dung, Nguyen Thi Nhan, Tran Thi Thuy,* * School of Chemical Engineering, Hanoi University of Science and Technology

Modification of Vietnam natural rubber via grafting copolymerization with styrene


41

POSTER PRESENTATION


42

Hydrogenation of natural rubber in latex stage may play a significant role to establish a green

technology in natural rubber field. The resulting material, i.e. hydrogenated natural rubber (HNR), is anticipated to be superior in the resistance to weather, heat, oxidation and chemical due to the saturated backbone. Furthermore, when the preparation of hydrogenated natural rubber is carried out in latex stage, we may establish a green procedure to prepare the green soft materials. Therefore, preparation of hydrogenated natural rubber in latex stage is of significant advantage to develop natural rubber field.

In the previous works, the researchers have been successful to prepare HNR latex with high conversion. However, the purification, i.e. the removal of the catalysts and by-products, of HNR latex is neglected in the previous works. In fact, the presence of catalysts or by-products may cause side reactions and decrease the reaction efficiency when HNR latex is subjected to the further modification. For example, graft-copolymerization of monomers onto HNR may be significantly affected, which the monomer conversion and grafting efficiency become lower, by the presence of catalysts or by-products. Therefore, it is necessary to develop a novel method of hydrogenation of NR in latex stage which enables the purification of the product after the hydrogenation to be simply carried out.

In the present work, the removal of proteins from natural rubber was carried out to prepare purified natural rubber for hydrogenation. The hydrogenation of NR in latex stage using palladium nano-particle catalyst and hydrogen gas was performed. The structural and properties characterization of HNR was carried out.

Nguyen Thu Ha 1*, Do Quoc Viet 1, Phan Trung Nghia 1, Seiichi Kawahara 2

1Hanoi University of Science and Technology, No.1 Dai Co Viet street, Hai Ba Trung district, Hanoi, Vietnam 2Nagaoka University of Technology, 940-2188 Nagaoka-shi, Niigata-ken, Japan.

* Corresponding to: [email protected]

Characterization of Hydrogenated Natural Rubber Prepared through Nano-particle Hydrogenation in Latex Stage


43

The production of alkanes from synthesis gas via the Fischer-Tropsch synthesis is known for

nearly 100 years1. Up to now, the parallel production of methane as side product still is a serious problem in efficient process development. Especially, the production of lower alkanes is accompanied with the formation of CH4

2. With this contribution we present a novel membrane based separation procedure for the removal of produced C2+ alkanes from the Fischer-Tropsch reaction mixture. The residual methane can be recycled and fed back to the reformer.

The purification of gases by membranes, especially porous inorganic membranes, has attracted a lot of attention in research and industry because of their thermal and chemical stability, good erosion resistance and high pressure stability. However, the improvement of porous inorganic membrane performance is a challenge in gas separation applications3. Concerning alkane separation it was found, that the membrane performance can be tremendously enhanced by choosing proper conditions45. Even a membrane with a significant number of defects or non-crystalized materials can give a high separation factor when liquefaction of higher alkanes occurs6.

In this work, mesoporous silica membranes have been used for the separation of a binary model mixture, namely n-butane/methane. The separation principle is based on capillary condensation: n-butane condenses in the pores of the membrane and blocks the pores for methane which can then not pass the separation layer. Several process parameters were investigated such as temperature, pressure, sweep gas flow rate and feed composition. The experimental results indicated that the n-butane separation efficiency (permeate flux and separation factor) through mesoporous silica membranes extremely increased when condensation takes place.

Moreover, multinary alkane mixtures were tested showing the application range of condensation membranes for the removal of methane from C2+-alkanes. With such a membrane processing step a much more efficient methane recycle to the reformer in the Fischer-Tropsch process is proposed.

1 F. Fischer, H. Tropsch, Brennst.-Chem. 4 (1923) 276 –285. 2 H. Jahangiri, J. Bennett, P. Mahjoubi, K. Wilson, S. Gu, Catalysis Science & Technology 4 (2014) 2210-2229. 3 N. Kosinov, J. Gascon, F. Kapteijn, E. J.M. Hensen, Journal of Membrane Science 499 (2016) 65-79. 4 K. Neubauer, R. Dragomirova, M. Stöhr, R. Mothes, U. Lubenau, D. Paschek, S. Wohlrab, J. Membr. Sci. 2014, 453, 100 – 107. 5 R. Dragomirova, M. Stohr, C. Hecker, U. Lubenau, D. Paschek, S. Wohlrab, RSC Adv. 2014, 4 (104), 59831 – 59834. 6 K. Neubauer, U. Lubenau, C. Hecker, B. Lücke, D. Paschek, S. Wohlrab, Chem. Ing. Tech. 2013, 85 (5), 713 – 722.

Thu H. A. Ngo1, Phuong N. X. Vo2, Marion Stöhr3, Sebastian Wohlrab3,* 1 Department of Chemical Technology, Faculty of Chemistry, VNU University of Science,

334 Nguyen Trai, Thanh Xuan District, Hanoi, 10000, Vietnam 2 PetroVietnam Research and Development Center for Petroleum Processing,

Vietnam Petroleum Institute, Vietnam Oil and Gas Group, Lot E2b-5, D1 Road, Saigon Hi-Tech Park, Tan Phu Ward, District 9, HoChiMinh City, Vietnam

3 Leibniz Institute for Catalysis, Albert-Einstein-Straße 29a, D-18059 Rostock, Germany

Separation of Fischer-Tropsch alkanes from methane by mesoporous silica membranes


44

Textile dyes and other industrial dyestuffs constitute one of the largest group of organic compounds that represent an increasing environmental danger. About 1–20% of the total world production of dyes is lost during the dyeing process and is released in the textile effluents1. In fact, the effluent streams coming from textile plants has to be treated in order to remove the toxic or carcinogenic dye residues and their by-products, whereas an effective effluent decolorization is usually required by most government regulations.

In the case of dye wastewater treatment, semiconductors are showing high potential as photocatalysts. Graphitic carbon nitride (g-C3N4), a 2-D π-conjugated polymeric, metal-free, mild band gap (2,7 eV) semiconductor has merged as an attractive material for various scientific application2,3. In recent times, many research are carried out to enhance the optical properties, surface area, charge separation and photodegradation kinetics of g-C3N4. Doping/decorating of various metallic species as alkali metals, transition metals and noble metals into g-C3N4 has been explored as effective ways to improve the photoactivity of this material (sodium doped g-C3N4

4, zirconium doped g-C3N4

5, silver deposited into g-C3N46…).

In this work, the photodegradation of methyl orange was studied with several kinds of metallic modified g-C3N4 materials as chromium (Cr) and iron (Fe) doping in comparison with bulk g-C3N4. Basically, Cr and Fe could be easily doped into g-C3N4 structure by dissolving corresponding salts with urea (as g-C3N4 precursor) in water before heating step. The materials were characterized by XRD, FT-IR and UV-Vis to evaluate the influence of the particular metal on the g-C3N4 structure. Moreover, the oxidation of g-C3N4 by using hydrogen peroxide (H2O2) with and without metal doping was also studied to clarify whether the presence of oxygen functionalized groups can further improve the photocatalytic performance of these materials under visible-light irradiation (λ > 420nm). The conversion of methyl orange into by-products with increasing irradiation time was followed by UV-Vis spectroscopy and HPLC.

1 A. Houas, H. Lachheb, M. Ksibi, E. Elaloui, C. Guillard, Jean-Marie Herrmann, Applied Catalysis B: Environmental. 2001, 31, 145 – 157. 2 G. Mamba, A.K. Mishra, Applied Catalysis B: Environmental. 2016, 198, 347 – 377. 3 M.N. Chong, B. Jin, C.W.K. Chow, C. Saint, Water Res. 2010, 44, 2997 – 3027. 4 X. Zhou, F. Peng, H. Wang, H. Yu, Y. Fang, Chem. Commun. 2011, 47, 10323 – 10325. 5 Y. Wang, Y. Li, H. Shi, Y. Xu, H. Qin, et al., Catal. Commun. 2015, 72, 24 – 28. 6 Z. Li, J. Wang, K. Zhu, F. Ma, A. Meng, Mater. Lett. 2015, 145, 167 – 170.

Vu Viet Thang1, Norbert Steinfeldt2,*

1 School of Chemical Engineering, Hanoi University of Science and Technology, 01 Dai Co Viet, Hai Ba Trung District, Hanoi, 10000, Vietnam

2 Leibniz Institute for Catalysis, Albert-Einstein-Straße 29a, D-18059 Rostock, Germany

Development of graphitic carbon nitride (g-C3N4) – based materials for visible light dye degradation


45

Abstract In organic electrosynthesis, the attachment of mediator to soluble polymer backbones

(polymediator) to create a homogeneous electrolyte represents a promising approach for improving both ionic conductivity and electron transfer kinetics. With respect to the redox-active unit, 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) is a robust, versatile and well-characterized mediator for homogeneously catalyzed electrochemical transformations. In this work, requirements for using TEMPO and Poly(TEMPO) as polymediator in the organic electrosynthesis of benzonitrile from benzyl alcohol have been investigated. The study has indicated that TEMPO and Poly(TEMPO) express catalytic activity in the electrosynthesis of benzonitrile from benzyl alcohol with the presence of ammonium acetate. The electrolysis yields of benzonitrile from benzyl alcohol with TEMPO and Poly(TEMPO) catalysts are 93 % and 40 %, respectively. The electrolysis yield of benzonitrile from benzaldehyde with Poly(TEMPO) catalyst is 58 %.

Luyen Tran Thi1,*, Benjamin Schille2, Robert Francke2 1School of Chemical Engineering, Hanoi University of Science and Technology, Hanoi, Vietnam

2Institute of Chemistry, University of Rostock, Rostock, Germany

TEMPO and Poly(TEMPO) catalysts for electrosynthesis of

benzonitrile from benzyl alcohol


46

Abstract In this work, the iron-impregnated fly ash was used as a heterogeneous Fenton-like catalyst for

the degradation of an antibiotic, cephalexin (CPX). The experimental conditions for the modification of fly ash and the treatment of CP were investigated, discussed, and optimized. The experimental results indicated that pH value, H2O2 dosage and the catalyst content are the main factors influencing the CPX treatment efficiency. Under the suitable conditions including hydrogen peroxide volume of 0.5 mL/L, catalyst dose of 1.2 g/L, and pH 3, 90% removal of CPX was achieved within 120 min of treatment. Kinetics studies confirmed that degradation of CPX followed a second-order reaction.

Nguyen Thi Minh Huong, Phan Thi To, Ho Thi Thuy, Dao Sy Duc

VNU University of Science, Vietnam National University-Hanoi 19 Le Thanh Tong Str., Hanoi, Vietnam

Degradation of cephalexin by heterogeneous Fenton catalyst using iron-modified fly ash


47

Nanoporous materials such as zeolites and metal organic frameworks (MOFs) are currently

studied predominantly in CO2 capture and separation because of their high internal surface area and micropore volume. The insight into site-specific adsorption properties of carbon dioxide in zeolites and MOFs are investigated by using X-ray and neutron diffraction. Our refinement of X-ray diffraction patterns on bare adsorbent KFI showed that Na+ locates in three different sites which are in D6R and 8MR, Li+ prefers to locate at the planes of the D6R, Mg2+ is located in the hexagonal prism and larger cation K+ is in the middle of 8-membered rings. An average T-O bond length is 1.635 Å and O-T-O bond angle is 109o, which is consistent with tetrahedral symmetry. Fourier map was used to locate the positions of CO2 molecules in zeolite KFI. At a high loading amount of nearly 1CO2/8MR, 3 different CO2 sites were all found on Na-KFI, Mg-KFI, Li-KFI, and K-KFI. The study of the interaction of CO2 with Li, Na, K, and Mg-KFI brings better understanding about the strength of CO2 interaction with extra-framework cations in KFI. Understanding the structure-property relationships between the dehydrated zeolite structures and CO2 adsorption behaviors can be the basis for designing and optimizing other adsorbents for CO2 capture

Keywords: X-ray, Diffraction, Adsorption, CO2. References T. D. Pham, et al., The molecular basis for the high CO2 adsorption capacity of chabazite zeolites,

Chemsuschem, 7 (2014), 3031-3038. T. D. Pham, et al., On the Structure–Property Relationships of Cation-Exchanged ZK-5 Zeolites for

CO2 Adsorption, ChemSusChem, 10 (2017), 946 –957.

Trong Pham*

*Department of Petrochemistry, Faculty of Chemistry, Vietnam National University, Hanoi, Vietnam

A synchrotron X-ray diffraction study of the adsorption of CO2 in KFI zeolite


48

Abstract Biochar derived from poultry manure was chemically activated with HNO3 and NH3 to prepare

amine-modified biochar (AMBC) bead for the removal of phenols from aqueous solution. The produced AMBC bead by the ammonia modification substantially increased the surface area up to 213.2 m2 g-1, which is higher than that of biochar without the modification. The present batch adsorption study focused on the phenol removal efficiency from aqueous solutions. The AMBC bead exhibited a higher adsorption potential for phenol than normal BC and commercial activated carbon. The maximum adsorption capacity of phenol by the AMBC beads reached 79.3 mg g-1. Phenol adsorption on the AMBC beads was well fitted with the Langmuir isotherm and a pseudo second-order kinetic model. The possible adsorption mechanism would involve interactions between phenol and nitrogen functional groups on the AMBC bead surface.

Keywords: Biochar bead; Kinetics; Langmuir; Phenol.

Nguyen Minh Viet, Nguyen Van Noi, Tran Dinh Trinh, Ha Minh Ngoc, Pham Thanh Dong *Key Laboratory of Advanced Material for Green Growth, Hanoi University of Science

Investigation of phenol adsorption by using amine-modified biochar beads


49

Abstract 3D materials are increasingly being researched, applied and developed in life. Because it has great

physical and chemical properties such as high mechanical strength, strong impact resistance, lightest material, large surface area, good electrical conductivity, good thermal insulation, many colors v.v. This material is mainly produced by two methods of supercritical drilling technique, sol-gel technique. Sol-gel technique has overcome many disadvantages of supercritical technology so it has been popular today. In this report, we have synthesized 3D rGO – nanoparticles composite material by hydrothermal method. The synthesized composite material has high porous surface and good distribution of nanoparticles on surface of rGO. The composite structure and morphology was characterized by FTIR and SEM. The high surface area and the presence of nanoparticles make this composite material become potential candidate for the catalyst in some process such as oxidation of the colored organic compounds through Fenton-like reaction.

Synthesis of 3D rGO - Nanoparticles Composite by Hydrothermal Method and its catalyst ability in oxidation of Methylene Blue

Nguyen Thi Hang, Dao Sy Duc and Nguyen Xuan Viet, Faculty of Chemistry, VNU – University of Science, Hanoi


50

One promising biomass-derived platform chemical is 5-hydroxymethylfurfural (HMF), which is

suitable for alternative polymers. The direct conversion of alkane diols and HMF into their mono and diesters has strong implications in polymerization reactions since the resulting products can be employed as monomeric units for condensation polymerization processes. When a diol has been used, the presence of second hydroxyl group in the reactant, however, would also reduce the ability of the esterification of the first hydroxyl group. This effect will depend on the length of the alkyl chain between the two hydroxyl groups. In our research, the oxidative esterification between HMF and alkane diols using different catalysts under mild conditions has been investigated.

Based on the results of the study, it will be broaden to the other corresponding alternative polymers by changing to the other monomer such as butylenediol. The long-term goal of the research would be the synthesis of the alternative polymers from the "real" bio HMF derived from natural cellulose of Vietnam using catalyst under mild conditions.

Nguyen Duy Hieu 1, Le Van Thai 1, Nguyen Thi Thao 1, Tran Thi Thuy 1, Esteban Mejia 2

1 School of Chemical Engineering, Hanoi University of Science and Technology 2 Leibniz Institute for Catalysis

Synthesis of novel monomers from 5-hydroxymethylfurdural (HMF) for the production of bio-based polymeric materials


51

Abstract In this study, the catalyst of 10% wt of CoxCuyOz (Cu:Co=1:1wt) on different carriers (MCM41,

Silica gel, Activated carbon) was prepared by wet impregnation method, then characterized by XAD, BET and SEM. Toluene oxidation over these catalysts was investigated and compared with the inlet concentrations (~20000 ppm), flow rates of 9.5 ccm and temperature range of 150-500oC with the rate at 2oC/min. The results show that the combination of these metal oxides can reduce the supports’ surface areas, but it can narrow the crystalline sizes of catalysts. Moreover, the carriers have effect on not only the adsorption capacities but also the oxidation activities. When the temperature is low (<300oC) these mixed metal on MCM41 and Silica gel do not have catalytic activities, but they have high activities at high temperature (>450 oC). However, at low temperature CoxCuyOz/activated carbon can oxidize toluene, but it is easy to be decomposed at high temperature.

Keywords. Toluene, Oxidation, Cobalt oxide, Cupper oxide, activated carbon, MCM41, silicagel. Acknowledgement. The authors thank to the supports of Rohan Program, DAAD, BMZ and

Laboratory of Petrochemical Refinering and Catalytic materials, HUTS

References

1. Sang Chai Kim, The catalytic oxidation of aromatic hydrocarbons over supported metal oxide, Journal of Hazardous Materials 91, 285-299 (2002).

2. Marco Piumetti, Debora Fino, Nunzio Russo, Mesoporous manganese oxides prepared by solution sombustion synthesis as catalysts for the total oxidation of VOCs, Applied Catalyst B: Environmental 163, 277-287 (2015).

3. L. Tidahy, S. Siffert, F. Wyrwalski, J.F. Lamonier, A. Aboukaı¨s, Catalytic activity of copper and palladium based catalysts for toluene total oxidation, Catalysis Today 119, 317-320 (2007).

4. Guilin Zhou, Xiaoling He, Sheng Lui, Hongmei Xie, Min Fu, Phenyl VOCs catalytic combustion on supported CoMn/AC oxide catalyst, Journal of Industrial and Engineering Chemistry 21, 932-941 (2015).

Corresponding author: Le Minh Thang School of Chemical Engineering - Ha Noi University of Science and Technology. Dai Co Viet Road, Hanoi, Vietnam. E-mail: [email protected] / [email protected]

Ngo Quoc Khanh 1 , Le Minh Thang 2,*, Vu Duc Thao2, Pham Thanh Trung 2 1 Vietnam National Institute of Occupational Safety and Health, 2 Hanoi University of Science and Technology, Hanoi, Vietnam

Study in toluen oxidation over catalysts of CoxCuyOz on different supports




52

Abstract The ring-opening polymerization (ROP) of ε-caprolactone synthesized in dichloromethane by using

dibutyl magnesium as a catalyst has been investigated. The polymerization was characterized by the linear dependence of semi-logarithmic plots of ε-caprolactone (ε-CL) concentration on reaction time and the linear in the relationship between initial rate and the amount of catalyst. Thus, the kinetic of the ROP was first-order in both monomer and catalyst concentration. The poly (ε-CL) was performed, and then was analyzed by 1H NMR, 13C NMR to determine its structure. The end group analysis suggests that the ε-CL polymerization might proceed through the ‘‘coordination-insertion’’. In addition, Gel Permeation Chromatography (GPC) has been used to determine the poly (ε-CL) molecular weight and distribution. The high molecular weight and low distribution (PDI = 1.1) were obtained.

Keywords: Ring-opening polymerization, poly (ε-caprolactone), dibutyl magnesium, coordination-

insertion.

Nhan Nguyen Hanoi University of Science and Technology

Synthesis of polycaprolactone by using magnesium compounds as catalysts


53

Vietnam is facing an increasing number of environmental pollution challenges including air, water,

and solid waste. The Recent report from Vietnam Ministry of Natural Resources and the Environment showed that air pollution in such big cities like Hanoi and Ho Chi Minh City was graded from unhealthy to hazardous for over 265 days of the year. The primary sources of urban air pollution are traffic and industrial activities. NOx (NO and NO2) which is discharged into the atmosphere mostly from anthropogenic sources including fossil fuel combustion of automobiles, power plants or industrial processes. They are considered to be toxic and chemical precursors that ubiquitous air pollutant in areas. The selective catalytic reduction (SCR) of NOx by ammonia is one of the most popular techniques for NOx emission control. Silicoaluminophotphat (SAPO) catalysts are potential eco-friendly catalysts for the low-temperature NH3-SCR of NOx. For the purpose of synthesizing SAPO catalysts by hydrothermal method from inexpensive raw materials, the study investigated the effect of structural directing agent (SDA) and synthesis conditions on the formation of SAPO structure, in which triethylamine (TEA) used as SDA. Products analyzed were characterized by XRD and SEM/EDS methods which related species were proved to be the SAPO catalysts structure.

Keywords: structural directing agent, NH3- SCR-NOx, Silicoaluminophotphat, triethylamine

Doan Anh Tuan1, Le Minh Thang2, Pham Thanh Huyen3* 1. School of Chemical Engineering, Hanoi University of Science and Technology 2. Department of Organic and Petro-chemical Technology, Hanoi University of Science and Technology 3. School of International Education, Hanoi University of Science and Technology

A Research on impact of structural directing agent and synthesis conditions to the formation of SAPO structure


54

Abstract Hydroformylation was found in 1938 which is one of the oldest and largest homogeneously

catalyzed reactions of olefins [1–3]. In hydroformylation, H2 and CO are added to the double bond of olefins to give aldehydes in the presence of a Co or Rh catalyst. A “heterogenized” type of homogeneous ionic liquid catalyst systems, described as Supported Ionic Liquid Phase (SILP) catalysts, which have circumvented the drawbacks of homogeneous hydroformylation and shortly apply for continuous flow, gas-phase operation [4,5,11]. However, studies with SILP catalysts for the hydroformylation of ethylene have not yet been reported much. In this work, supported ionic liquid phase (SILP) catalysts with two ligand TPPTS-Na3 & TPPTS-Cs3 using mesoporous TiO2 supports were prepared and applied to continuous, gas-phase hydroformylation of ethylene. Ionic loading contents influence significantly on activities and surface area of SILP catalysts. The formation of Rh-complexes as well as deactivation of SILP catalysts caused by decomposition of Rh-complexes were confirmed by new method EPR spectroscopy.

Keywords: SILP, TiO2, ethylene, propanal, deactivation. Acknowledgments This work has been supported by the RoHan Project funded by the German Academic Exchange

Service (DAAD, No. 57315854) and the Federal Ministry for Economic Cooperation and Development (BMZ) inside the framework "SDG Bilateral Graduate school programme”.

References 1. B.C. Gates, J.M. Katzer, G.C.A. Schuit, Chemistry of Catalytic Processes, McGraw-Hill, 1979. 2. G.M. Wells, Handbook of Petrochemicals and Processes, Second Edition Gower Publishing

Company, 1995. 3. S. Bhaduri, D.Mukesh, Homogeneous Catalysis:Mechanisms and Industrial Applica-tions, John

Wiley & Sons, 2000. 4. A. Riisager, R. Fehrmann, M. Haumann, P. Wasserscheid, Topics in Catalysis 40 (2006) 91–102. 5. A. Riisager, R. Fehrmann, M. Haumann, B.S.K. Gorle, P. Wasserscheid, Industrial and

Engineering Chemistry Research 44 (2005) 9853–9859. 6. C. Deng, G. Ou, J. She, Y. Yuan, Journal of Molecular Catalysis A: Chemical 270 (2007) 76–82. 7. M. Haumann, M. Jakuttis, S. Werner, P. Wasserscheid, Journal of Catalysis 263 (2009) 321–327. 8. W.J. Tenn, R.C. Singley, B.R. Rodriguez, J.C. DellaMe, Catalysis Communications 12 (2011)

1323–1327. 9. M.J. Naughton, R.S. Dragot, Journal of Molecular Catalysis A: Chemical 155 (2000) 383–389. 10. T. Yamagishi, I. Furikado, S. Ito, T. Miyao, S. Naito, K. Tomishige, K. Kunimori, Journal of

Molecular Catalysis A: Chemical 244 (2006) 201–212. 11. A. Riisager, K.M. Eriksen, J. Hjortkjær, R. Fehrmann, Journal of Molecular Catalysis A: Chemical

193 (2003) 259–272.

Truong Duc Duc1, Le Minh Thang1 1 School of Chemical Engineering, Hanoi University of Science and Technology, Hanoi, VIETNAM.

The formation of Rh-complexes and deactivation of supported ionic liquid phase (SILP) catalysts in hydroformylation of ethylene


55

Two-step sequential procedures for the practical Pd-catalyzed synthesis of 5- and 6-azaindoles are reported in very good isolated yields. An easy access to 6-azaindoles is described via the first site-selective Pd-catalyzed Sonogashira reaction of 3,4-dibromopyridine with alkynes, then followed by Pd-catalyzed tandem C-N coupling and cyclization with amines. On the other hand, a convenient approach to 5-azaindoles is successfully completed by site-selective Pd-catalyzed C-N coupling reaction of 3,4-dibromopyridine with amines followed by C-C coupling and cyclization with alkynes.

Nguyen Thi Son,1 Marian Blanco Ponce,2 Tuan Anh Nguyen Tien,1 Peter Ehlers, Tuan Thanh Dang,1,* Peter Langer2,*

1 Department of Organic Chemistry, Faculty of Chemistry, VNU University of Science, 334 Nguyen Trai, Thanh Xuan District, Hanoi, 10000, Vietnam

2 Institute of Chemistry, Universität Rostock, Albert-Einstein-Str. 3a, 18059 Rostock, Germany

Efficient Synthesis of 5- and 6-azaindoles by Sequential Site-selective Pd-catalyzed C–C and C–N coupling reactions

eparation of Fischer-Tropsch alkanes from methane by mesoporous silica membranes


56

Methyl Orange (MO) is one of the most popular azo dye sources, it mainly comes from the

industrial textile and printing waste water. There are some common degradation methods of Methyl Orange, a toxic substance for the environment and human beings such as physical, biological and traditional advanced oxidation processes. However, these methods were sometime expensive and often inefficient at low concentrations of MO. Recently, one of most potential techniques for dye source waste water treatment is using semiconductor photocatalysis technology as TiO2. Generally there are two forms of TiO2 applied in photocatalysis: dispersed fine particles and immobilized particles such as thin films on various substrates.

In this research both kinds of TiO2 forms were synthesized with different methods and conditions to evaluate their performance for MO photodegradation with both full range and UV light.

The first direction, Graphene Oxide (GO)-TiO2 is synthesized by Sol-gel method from the precursor Tetraisopropyl Orthotitanate and Graphene Oxide (GO) prepared using Hummer modified method with graphite powder and other substances. Nano-sized powder of GO-TiO2 has been prepared suscessfully from Titanium Isopropoxide precusor via Sol-gel methods with various GO content in final powder catalysts. All samples characterized with BET show that catalysts are mesopporous and their surface areas nearly the same as 90m2/g. The GO ratio influenced significantly on the photoactivity of GO-TiO2 catalyst with MO solution. The catalyst GO-TiO2 synthesized using sol-gel method with ratio GO:TiO2 as 1:18 exhibited the highest activity as 78% with full range light (Xenon lamp) after 6 hours. However, this catalyst degraded up to 94% MO only after 2 hours with UV-C light ( High Pressure Vacuum Mercury lamp).

In the second form, TiO2 photocatalyst films on ceramic, glass, aluminium surfaces were prepared by the low-pressure chemical vapor deposition (LPMOCVD) with titanium-tetraisoproposide (TTIP) to determine the optimum condition for MO photocatalytic activity. Many parameters such as temperature of precursor solution (TTIP) and material surfaces (ceramic, glass, aluminium), flow rate of gas carrier (nitrogen) and vacuum pressure were evaluated. The optmium condition were confirmed with titanium-tetraisoproposide (TIIP) 98% temperature 80°C,reaction chamber temperature 300°C, vacuum pressure 700mmbar, nitrogen gas flow rate 100ml/minute and oxygen 500ml/minute, CVD reaction duration 30 minutes. The characterization results of spectroscopic vision and SEM-EDS indicate the nature of surface materials having strong effect to TiO2 thin films. Their MO photocatalytic degradations with full range and UV-C lamps give the contrast results. In UV-C condition, 52% MO was degraded with TiO2 thin film on ceramic only after 2 hours. However, this thin film only 11% MO degraded after over 10 hours lighting in full range condition with Xenon lamp.

From the above results, it is indicated that TiO2 catalyst should be improved more their performance especially in full range light condition. Our group also express deep gratitude towards RoHan program for supporting us to conduct this research.

Keywords: Methyl Orange treatment, GO-TiO2, sol-gel, TiO2 thin film, chemical vapor deposition

Nguyen Trung Hieu, Vu Anh Tuan, Le Minh Thang School of Chemical Engineering, Ha Noi University of Science and Technology

Synthesis nano TiO2-GO powder and TiO2 thin film by Sol-gel and Chemical Vapor Deposition methods for Methyl Orange

Photocatalytic degradation in full range and UV light condition


57

To transform the methane oxidation to methanol in a selective, straight, economically attractive,

and less energy intense process is a goal pursued by the industry since its discovery. Methane is the main constituent of shale and natural gas while methanol is either a fuel as feedstock in the chemical industry. The request for an efficient process to convert methane efficiently to fuels and high value-added chemicals such as olefins and aromatics is motivated by their increasing demands and recently discovered large reserves and resources of methane. Thus, to develop a technology that combines an affordable raw material with a strategic product became pivotally important for the chemical industry [1]. A number of metal oxides were tested. Boomer and Naldrett moved away from the copper catalysts previously studied in their group to silver-, zinc-, and nickel- based catalysts. Likewise, through the 1960s, a number of Russian scientists examined oxides of zinc, cobalt, aluminum, iron and molybdenum. Atroshchenko et al. found molybdenum trioxide and chromium oxide to be active for the partial oxidation of methane at elevated temperatures and pressures [2]. Industral catalysts used for conversion of methane are BASF's ZnO-Cr2O3 catalysts in the early 1920s, ICI in 1960 developed a synthetic orientation at low pressure (5 - 10Mpa, To = 200 - 300oC) on CuO catalyst with high selectivity. In this study, we were synthesized CuO catalysts to add some elements such as Co, Mo,... with the aim to increase the activity and selectivity of methane conversion products.

References [1] Márcio José da Silva, Synthesis of methanol from methane: Challenges and advances on the

multi-step (syngas) and one-step routes (DMTM), 2016.01.023, 2016 in Fuel Processing Technology [IF: 3.75.

[2] Manoj Ravi Dr. Marco Ranocchiari Prof. Dr. Jeroen A. van Bokhoven, The Direct Catalytic Oxidation of Methane to Methanol—A Critical Assessment, 23 June 2017.

Vu Quoc Quan, Pham Thi Mai Phuong, Le Minh Thang Ha Noi University of Science and Technology, Dai Co Viet Road, Ha Noi, Viet Nam

The influence of Co, Mo on CuO doped catalysts for the direct conversion of methane


58

ZSM-5 zeolite is a microporous aluminosilicate material with well-defined pore structures and

compositions, which is widely used as acid catalyst in alkylation, acylation, isomerization, and especial aromatization. Converting low alkanes (C2 – C6) into aromatic compounds is great industrial interest, number of processes such as the Cyclar (BP-UOP) , M-2 forming (Mobil) and Aroforming (IFP/SALUTEC) are available. Many studies on the aromatization of light hydrocarbons shown that ZSM-5 containing Zn or Ga are the most suitable for this kind of reaction. The bifunctional catalyst provides metal sites for the dehydrogenation and hydrogenation; acid sites for the oligomerization, isomerization and cyclization to convert light n-paraffin to BTX products. The structure of ZSM-5 and loadings of Zinc significantly affected the reaction activity. E. Rojasova et al. supposed that the present of Zn causes acid-site strength redistribution and generation of new relatively strong Lewis acid sites. Zinc will evaporate at high temperature (over 600oC) that can lead to the deactivation of the catalyst, therefore, the promoters must be added to prevent this phenomenon.

In this work, Zn/ZSM-5 and Zn-B/ZSM-5 catalysts were prepared by incipient wetness impregnation and will be characterized and tested for the aromatization of n-hexane.

*Vu Dinh Trinh1, Cristina Martínez2*, Pham Thanh Huyen1* 1School of Chemical Engineering, Hanoi University of Science and Technology, Vietnam,

2 Instituto de Tecnología Química, Universitat Politècnica de València – Consejo Superior de Investigaciones Científicas, Spain

*Email: [email protected]

*Affiliation

Aromatization of n-hexane over Zn-modified nano-ZSM-5 zeolite catalyst



59

Serie of x% (wt) g-C3N4/TiO2 composites was synthesized by different adequate mechanical

mixture of Ti(OH)4 and g-C3N4, followed by a calcination at 400oC in air for 3 hours. The composites were characterized by different techniques such as XRD, IR, UV-DRS and PL spectra. These XRD and IR results have indicated the existence of TiO2 anatase phase and layer structure of g-C3N4 in all composites. The UV-DRS spectra of the composites showed the absorption zone shift in visible-light one with respect to TiO2. Their charge separation was also elucidated by PL spectra. The photocatalytic activity was estimated through photodegradation of methylene blue. The initial results showed the highest degradation yield of 97% after 3h irradiation on 30% g-C3N4/TiO2. This result seems to be due to the smallest ban gap value of 2.3 eV and good charge separation of this composite.

Thomas Baubrand1, Dinh Thi Thuy Hang2, Nguyen Minh Hai3, Le Thanh Son3, Nguyen Thanh Binh3* 1 Chemistry Department, Université Paris-Est Créteil, Paris, France

2 Maritime University of Vietnam, Hai Phong, Vietnam 3 Hanoi University of Science, Vietnam National University, Hanoi, Vietnam

*Corresponding author: [email protected]

*Affiliation

Synthesis and characterization of composites x% g-C3N4/TiO2



60

For biocatalysis either isolated enzymes or whole cells can be used for conversion of a given

starting material. Whereas cells are mainly used in aqueous environment enzymes in soluble or

immobilized form may be used in water or even organic solvents or in mono- or biphasic mixtures.

After a short historic overview a discussion of the solvents and the interaction with the

biocatalyst is presented. The following examples for industrial processes will be discussed:

- Chiral amines (kinetic resolution)

- Chiral glycidylesters (kinetic resolution)

- Hydroxynitriles (enantioselective C-C-bonding

- Chiral alcohols (enantioselective reduction)

- Building blocks for Cephalosporines (regioselective oxidation)

- Acrylamide (selective addition of water)

In addition some tools for process development such as microreactors will be discussed

allowing for example much higher oxygen transfer reactions for laccase catalyzed oxidation reactions.

Udo Kragl

University of Rostock, Department of Chemistry, 18051 Rostock, Germany

Biocatalytic Reactions for Synthesis of Fine and Bulk Chemicals


61

ABSTRACT Previously, synthesis of 6-nitro- and 6-aminoquinolones was reported, starting from ortho-halogenated aryl alkynones and various amines.[1] In comparison, variation of the starting amine to an amino acid have led to a significant change of the product in this reaction This report will describe a new method to synthesize multi-functionalized Chromeno[2,3-c] pyrrol-9(2H)-ones. The synthesis is based on a Sonogashira coupling followed by a domino reaction with an amino acid in the present of a base giving corresponding products in moderate to high yield. Keywords: Sonogashira, amino acid, cyclization, domino reaction, Palladium. Acknowledgments This work has been supported by the RoHan Project funded by the German Academic Exchange Service (DAAD, No. 57315854) and the Federal Ministry for Economic Cooperation and Development (BMZ) inside the framework "SDG Bilateral Graduate school programme”. References

[1] M. Milyutina, A. Ivanov, S. Ejaz, J. Iqbal, A. Villinger, V. O. Iaroshenko and P. Langer, RSC Adv., 2015, 5, 60054-60078

Tuan Anh Nguyen Tien,a Peter Ehlers,b Maria Milyutina,b Peter Langer,b a) Faculty of Chemistry, VNU-Hanoi University of Science, 19 Le Thanh Tong, Hanoi, Vietnam.

E-mail: [email protected] b) Institut für Chemie, Universität Rostock, Albert-Einstein-Str. 3a, 18059 Rostock, Germany.

A new synthetic strategy to annulated Chromeno[2,3-c]pyrrol-9(2H)-ones


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