PreparationofFe(II)/MOF-5CatalystforHighlySelective ... · 2019. 11. 7. · A 3-mouth ﬂask, EL204...

Research ArticlePreparation of Fe(II)MOF-5 Catalyst for Highly SelectiveCatalytic Hydroxylation of Phenol by Equivalent Loading atRoom Temperature

Bai-Lin Xiang 123 Lin Fu1 Yongfei Li 1 and Yuejin Liu 1

1College of Chemistry Engineering Xiangtan University Xiangtan 411000 China2College of Chemistry and Materials Engineering Huaihua University Huaihua 418000 China3Hunan Engineering Laboratory for Preparation Technology of Polyvinyl Alcohol (PVA) Fiber MaterialCollege of Chemistry and Materials Engineering Huaihua University Huaihua 418000 China

Correspondence should be addressed to Yongfei Li liyongfei98163com and Yuejin Liu xdlyj163com

Received 27 June 2019 Revised 28 August 2019 Accepted 30 September 2019 Published 7 November 2019

Academic Editor Claudia G Silva

Copyright copy 2019 Bai-Lin Xiang et al 1is is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work isproperly cited

1e metal-organic framework MOF-5 was synthesized by self-assembling of Zn(NO3)2middot7H2O and H2BDC using DMF as solventby the direct precipitation method and loaded with Fe2+ by the equivalent loading method at room temperature to prepare Fe(II)MOF-5 catalyst and the microstructure phases and pore size of which was characterized by IR XRD SEM TEM and BET It wasfound that Fe(II)MOF-5 had high specific surface and porosity like MOF-5 and uniform pore distribution and the pore size is12 nm In order to study the catalytic activity and reaction conditions of Fe(II)MOF-5 it was used to catalyze the hydroxylationreaction of phenol with hydrogen peroxide 1e results showed that the dihydroxybenzene yield of 532 and the catecholselectivity of 986 were obtained at the Fe2+ content of 3 wt the mass ratio of Fe(II)MOF-5 to phenol of 0053 the reactiontemperature of 80degC and the reaction time of 2 h

1 Introduction

Dihydroxybenzenes mainly include catechol and hydro-quinone and are important organic intermediates for syn-thesis of carbofuran propoxur berberine and epinephrinevanillin piperonal etc In addition dihydroxybenzenes areused for dyes photosensitive materials electroplating ma-terials special inks auxiliaries etc [1] As an important finechemical intermediate product catechol (CAT) is widelyused in the fields of pesticides (about half of the globalcatechol consumption) spices and medicine [2]

1e process of dihydroxybenzene preparation from di-rect oxidization of phenol by hydrogen peroxide was a greenproduction process because of simple process mild reactionconditions water as by-product and no environmentalpollution [3ndash6] However a catalyst is must required for

direct oxidization of phenol by hydrogen peroxide iehydroxylation of phenol1us it is very important to select asuitable catalyst for phenol hydroxylation 1e catalysts forphenol hydroxylation include modified molecular sievescomposite metal oxides organic metal complexes etc [7ndash9]It has been reported that the phenol conversion of thesecatalysts for phenol hydroxylation was usually between 40and 60 and the catechol selectivity was seldom more than75 [10ndash12] According to Adam et al [13] the molecularsieve catalyst (FeKL) catalyzed phenol hydroxylation withthe conversion of 934 but the catechol selectivity was only7747 Zheng et al [14] prepared the CD-MOF-cat catalystwhich catalyzed phenol hydroxylation with the conversionof 86 and catechol selectivity of 737 Hu [15] synthesizedthe hexadecyl pyridinium salt of As-Mo-V heteropolyacidwhich catalyzed phenol hydroxylation in acetonitrile as

HindawiJournal of ChemistryVolume 2019 Article ID 8950630 10 pageshttpsdoiorg10115520198950630

solvent with the catechol selectivity of 873 but the phenolconversion was only 1711erefore it is very important todevelop a catalyst with high phenol conversion and catecholselectivity

Metal-organic frameworks (MOFs) are new nano-porous frameworks with periodic network structureformed by self-assembling of nitrogen or oxygen-con-taining organic ligands and transition metal ions throughcomplexation [16] MOFs have well-ordered tunable po-rous structures with a wide range of pore sizes and ex-ceptional textural properties of high surface areas and highpore volumes which can afford a variety of applications ingas adsorptionseparation and heterogeneous catalysis[17] When MOFs is used as a homogeneous catalyst it hasbeen used for the following reactions (a) aerobic oxidationof tetralin [18 19] (b) phenol hydroxylation [20] (c)oxidative desulfurization of dibenzothiophene [21] (d)Knoevenagel condensation reaction [22 23] (e) one potdeacetalization-nitroaldol reaction [24] (f ) FriedelndashCraftacylation [25] (g) CO2 cycloaddition of epoxides [26] (h)heck reaction [27] and (i) epoxidation of alkenes [28] As atypical representative of the metal-organic frameworkcomplex family MOF-5 was a framework with a three-dimensional structure high specific surface and well-de-fined pore structure formed by connecting an inorganicgroup [Zn4O] consisting of four zinc and one O toP-phenylene dimethyl [29] It has much higher specificsurface and pore volume than activated carbon zeolitemolecular sieves and silica Kaye et al in Yaghi team [30]reported a MOF-5 with the specific surface area of 2900m2g Perez et al [31] reported a MOF-5 with the specificsurface area of 3362m2g MOF-5 has a shape-selectiveeffect in specific catalytic reactions because of its con-trollable pore size and orderly pore size [32ndash35] which ishelpful to improve the selectivity of the reactions MOF-5was also often used as a carrier to support different catalyticactive sites such as Pt Au and Pd to prepare MOF-basedcatalysts [36ndash39] for different heterogeneous catalytic re-actions with good catalytic effect For example Liu et al[40] have reported the catalyst AuMOF-5 which supportedAu on a functionalized MOF-5 by the impregnationmethod 1e results showed that the AuMOF-5 catalystdisplayed high activity and 100 selectivity forpropargylamines

In addition many transition metals such as Cu MnMo and Fe have the activity to catalyze phenol hydrox-ylation but Fe-supported catalysts are used more fre-quently For example the Fe-supported bentonite catalystprepared by RESTU [41] and FeAl-MCM-41 prepared byPreethi et al [42] show better catalytic activity thanother transition metals Also some Fe-supported catalystsshowed good selectivity in some oxidation reactions[43 44]

In this paper Fe2+-supportedMOF-5 was synthesized bythe direct precipitation method and used for phenol hy-droxylation MOF-5 cannot withstand high temperatureabove 400degC [45] so Fe(II)MOF-5 was prepared by

equivalent loading of Fe2+ at low temperature [46] and usedto catalyze hydroxylation of phenol by hydrogen peroxide inorder to study the performance of the Fe(II)MOF-5 catalystand technological conditions of hydroxylation of phenol byhydrogen peroxide

2 Experimental

21 Reagents and Apparatuses All chemicals in this studywere directly used without any purification Zn(NO3)2middot6H2O terephthalicacid DMF(NN-dimethylformamide)triethylamine FeSO4middot7H2O phenol hydrogen peroxide(30) deionized water and ethyl acetate are all chemicallypure

A 3-mouth flask EL204 analytical balance round-bot-tom flask beaker funnel DF-101S constant temperaturemagnetic stirrer liquid separating funnel gas chromatog-raphy-mass spectrometry were used (Shimadzu GCMS2010-plus)

22 Direct Precipitation Synthesis of MOF-5 3 g ofZn(NO3)2middot6H2O and 1275 g of di-2-hydroxyethyl tere-phthalate were weighed to three flasks 100mL of DMF wasadded1emixture was well mixed at room temperature untila clear solution was obtained Triethylamine (4 g 55mL) wasdropwise added under violent agitation 1e solution grad-ually became turbid After that the solution was stirred for 3 hand filtered at vacuum 1e cake was washed with DMF(3times 20mL) and dried at 120degC to form MOF-5 [46]

23 Preparation of Fe(II)MOF-5 by the Equivalent LoadingMethod Based on 5 g of MOF-5 the mass of FeSO4middot7H2Owas calculated according to the Fe2+ loading of 1 2 34 5 6 and 7 (wt) respectively FeSO4middot7H2O wasweighed to a conical bottle containing DMF (the volume ofDMF was equal to that of 5 g of MOF-5) and dissolved underagitation at room temperature 5 g of MOF-5 was added tothe solution Meanwhile MOF-5 was just immersed in DMFsolution1e solution was well mixed and dried at vacuum at90degC for 2 h to obtain Fe(II)MOF-5 with the Fe2+ loading of1 2 3 4 5 6 and 7

24 Hydroxylation of Phenol 05 g of Fe(II)MOF-5 90mLof phenol 160mL of hydrogen peroxide (30) and 300mLof deionized water were taken to a round-bottom flaskwhere the reaction lasted for 1sim3 h under magnetic agitationat 80degC At the end of the reaction the solution was filtrated1e filtrate was extracted by ethyl acetate three times 1eextract was tested on phenol and dihydroxybenzene contentsby gas chromatography-mass spectrometry (GCMS 2010-plus) 1e filtrate was distilled to remove all liquids andobtain a small amount of solid (tar) on the flask wall 1e tarwas weighed 1e yield of catechol hydroquinone benzo-diazepine and the selectivity of catechol were calculated bythe following formula

2 Journal of Chemistry

Xphenol mphenol minus mphenol(R)

mphenol

SCAT 94mCAT

110 mphenol minus mphenol(R)1113872 1113873

YCAT Xphenol middot SCAT

SHQ 94mHQ


YDHB YCAT + YHQ

YHQ Xphenol middot SHQ

(1)

where mphenol is the mass of phenol before reactionmphenol(R) is the mass of phenol after reaction Xphenol is theconversion of phenol SCAT is the selectivity of catecholSHQ is the selectivity of hydroquinone YCAT is the yield ofcatechol YHQ is the yield of hydroquinone and YDHB is theyield of benzodiazepine

25 Characterization of Catalyst 1e catalyst samples weremeasured using a Rigaku UltimaIV XRD system with Cu-Kαradiation (λ 01542 nm) 1e target voltage and currentwere 40 kV and 30mA respectively 1e 2θ scan range andrate were 3sim50deg and 8degminminus 1 respectively A FTS 165 Fouriertransform infrared spectrometer was used to measure thecatalyst samples with KBr pellets Transmission light wasused to scan within a range of 4000sim400 cmminus l 1e catalystsamples were observed under a ZEISS Sigma HD fieldemission scanning electron microscopy (FESEM) 1e ac-celerating voltage was 8 kV 1e morphology was observedusing the secondary electron detectors in lens Meanwhilethe element contents in the samples were analyzed using anOxford X-Max electric energy spectrum meter (X-MaxN)TEM of the samples was obtained using a JEOL JEM-2010UHR transmission electron microscope with an acceleratingvoltage of 200 kV 1e Brunauerminus Emmettminus Teller (BET)specific surface areas were measured on Belsorp-Mini IIanalyzer (Japan)

3 Results and Discussion

31 Catalyst Structure Characterization

311 XRD Analysis Figure 1 shows the Fe(II)MOF-5samples with different Fe2+ loadings (0 1 2 3 45 6 and 7 respectively) 1e main four characteristicpeaks of MOF-5 were at 2θ 68deg 97deg 137deg and 154deg [46]2θ 68deg in the small corner area represented lt200gt crystalplane and 2θ 97deg represented lt220gt crystal plane [47] Itcould be seen from Figure 1 that the characteristic peaks ofthe prepared MOF-5 were consistent with those reported inthe literature We also found that the characteristic peakintensity of the catalyst decreased with the increase in Fe2+loading from Figure 1 1is was because the widened dif-fraction peaks resulting from fineness and small grain size of

Fe2+-supported catalyst crystal But Fe2+ had little influenceon the crystal structure of MOF-5 because the characteristicpeaks of the sample still existed However no obviouscharacteristic peak of Fe2+ was found in XRD spectra maybedue to the low loading of Fe2+ or the small size and highdispersion of Fe2+ particles In addition MOF-5 and Fe(II)MOF-5 were very different in color MOF-5 was white whileFe(II)MOF-5 was brown Fe(II)MOF-5 became darkerwith the increase in Fe2+ loading

312 Infrared Spectrometry Analysis Figure 2 shows theinfrared spectra of Fe(II)MOF-5 with different Fe(II)MOF-5 loadings It could be seen from Figure 2 thatMOF-5 and Fe(II)MOF-5 samples basically had thecharacteristic peaks 1e peak at 750 cmminus 1 was thestretching vibration of Zn-O in tetrahedral Zn4O crystalclusters 1e peaks at 1388 cmminus 1 and 1580 cmminus 1 were twostrong absorption peaks ie stretching vibration peaks of-CO in -COO-Zn2+ including asymmetric and sym-metric stretching vibration peaks of-CO respectivelyand the peak at 1652 cmminus 1 was the asymmetrical stretchingvibration of the C-O-O bond It could be seen fromcomparison of the infrared spectra that the loading of Fe2+did not influence the chemical structure of MOF-5

313 SEM and Energy Dispersive Spectrometry AnalysisFigure 3(a) shows the SEM images of MOF-5 andFigure 3(b) shows the SEM photograph of Fe(II)MOF-5with Fe2+ loading of 3

Figure 3(a) shows that MOF-5 had a lot of wafer with thesize of 50ndash300 nm and had relatively smooth surface andsome voids and channels between particles Figure 3(b)shows that Fe(II)MOF-5 with Fe2+ loading of 3 hadsimilar morphology compared with MOF-5 ie some of thecrystalline blocks are stuck together but there were hadmore voids between the crystalline blocks than MOF-5

Figure 4 is the energy dispersive spectrum of Fe(II)MOF-5 with 3 Fe2+ loading It could be seen that Fe atomspresent in Fe(II)MOF-5 showing successful loading of Fe2+

Fe(II)MOF-5

6 Fe2+

5 Fe2+

4 Fe2+

3 Fe2+

2 Fe2+

1 Fe2+

0 Fe2+

2-theta (deg)

Inte

nsity

(cou

nts)

10 20 30 40 50 60

Figure 1 XRD patterns of Fe(II)MOF-5

Journal of Chemistry 3

ontoMOF-51e loading (about 34 wt) of Fe2+ calculatedfrom the EDS (Table 1) is near to the initial adding amount(3wt) 1e catalyst of Fe(II)MOF-5 (containing 3 Fe2+)was further characterized by element mapping 1e resultsare shown in Figure 5 We found that the catalyst contains CO Zn and Fe elements And we can clearly see that thecatalyst has relatively uniform Fe distribution indicatinguniform loading of Fe ions on the catalysts

314 TEM and Pore Size Distribution Figures 6(a) and 6(b)are TEM images of MOF-5 and Fe(II)MOF-5 catalystrespectively It is clear that MOF-5 and Fe(II)MOF-5 both

had regular channel structures and the channel width wasabout 1-2 nm Also it could be seen that Fe2+ loading did notgreatly influence the channel structure of MOF-5 Figure 7shows the pore size distribution of MOF-5 and Fe (II)MOF-5 with Fe2+ loading of 1 3 and 5 respectively 1eirpore sizes were mainly at 12 nm corresponding to those sizeobserved by TEM

32 Phenol Hydroxylation

321 Comparison of Catalytic Activity 1e results of phenolhydroxylation by hydrogen peroxide which was catalyzed byFe(II)MOF-5 catalysts with different Fe2+ loadings (1 23 4 5 6 and 7 respectively) are shown in Table 2

It could be concluded from Table 1 that (1) no productwas generated when MOF-5 was used as catalyst in a blankexperiment (2) MOF-5 with Fe2+ loading of 3 had the bestcatalytic effect and provided the dihydroxybenzene yield of532 (Figure 8) (3) no hydroquinone was detected and theselectivity of catechol was 986 when the weight of tar wastaken into account With increasing Fe2+ loading below 3

(b)(a)

Figure 3 SEM images of MOF-5 and Fe(II)MOF-5 (3 Fe2+)

0 1 2 3 4 5 kev

200μm

Figure 4 X-MaxN energy spectrum of Fe(II)MOF-5 (3 Fe2+)

Table 1 Element content of Fe(II)MOF-5 (3 Fe2+)

Element C O Fe ZnMass () 3681 3855 340 2124Mol () 5247 4093 104 556

Tran

smitt

ance

Fe(II)MOF-5

6 Fe2+

5 Fe2+

4 Fe2+3 Fe2+2 Fe2+

1 Fe2+

0 Fe2+

Wavenumber (cmndash1)4000 3500 3000 2500 2000 1500 1000

Figure 2 IR spectra of Fe (II)MOF-5


the yield of dihydroxybenzene increased However withincreasing Fe2+ loading above 3 the yield of dihydrox-ybenzene decreased gradually 1is might be becausethe increase in Fe2+ loading easily led to the rapid

decomposition of H2O2 into oxygen and water resulting inthe lower utilization rate of H2O2 and lower catalytic effi-ciency [10 48] In addition it has been found that theamount of bubbles increased with the increasing content ofFe which indirectly proves that the increase in Fe will ac-celerate the decomposition of H2O2 into H2O and O2

No matter what the loading of Fe2+ was the selectivity ofcatechol was relatively high (up to 986) in the reaction1is might be due to the small and uniform pore size(12 nm) of Fe(II)MOF-5 (Figures 6 and 7) TEM imageshowed that the pore size distribution of MOF-5 was uni-form which made small size single molecule phenol orcatechol easy to diffuse in the pore However hydroxylgroups of hydroquinone could easily interact with each otherto form a multimolecular hydrogen bond associationproduct [49] (Figure 9) and this makes it difficult to diffusein the channels of catalyst 1erefore those lead to a shape-selection effect [32] and the selectivity of catechol was veryhigh However dihydroxybenzene was easily oxidized se-verely to macromolecular substances such as tar [50] whichcauses catechol selectivity below 100

Compared with our previous work [51] the catalyticactivity of Fe2+MOF-5 showed a higher yield of dihy-droxybenzene (532) than that of pure Fe3+MOF-5 (37)

C O

Zn Fe

Figure 5 Element mapping of Fe(II)MOF-5 (3 Fe2+)

(a) (b)

Figure 6 TEM images of the samples (a) MOF-5 and (b) Fe(II)MOF-5

MOF-5Fe(II)MOF-5 (1)

Fe(II)MOF-5 (3)Fe(II)MOF-5 (5)

00000

00005

00010

00015

00020

00025

00030

00035

00040

00045

dVp

drp

100101rp (nm)

Figure 7 Pore size distribution of the samples


due the oxidation of Fe2+ to Fe3+ by H2O2 in the liquid phasewhich resulted in the coexistence of Fe2+ and Fe3+ and thusin an increase in dihydroxybenzene yield [52]

322 Influence of Reaction Temperature 1e hydroxylationof phenol by hydrogen peroxide was catalyzed by Fe(II)MOF-5 with Fe2+ loading of 3 at different reaction tem-peratures 1e results are listed in Table 3

It could be seen from Table 3 that almost no dihy-droxybenzene was formed at 50sim60degC 1e yield of dihy-droxybenzene was 484 and the selectivity of catechol was854 at 70degC the yield of catechol was 532 and theselectivity of catechol was 986 at 80degC 1e optimal re-action temperature was 80degC due to too fast decompositionof H2O2 above 80degC

323 Influence of Reaction Time Table 4 shows the effect ofreaction time on the hydroxylation of phenol catalyzed byFe(II)MOF-5 with Fe2+ loading of 3 It could be seen thatalmost no product was formed at 05 h with the increase inreaction time the yield of catechol first increased and then

decreased and the selectivity of catechol was above than95 the produced catechol was easily oxidized to macro-molecular substances such as tar [50] resulting in a decreasein the dihydroxybenzene yield 1e solutions had signifi-cantly darker color at 3 h than at 2 h (Figure 10) aftercomplete evaporation of each solution it was found that thetar content was higher at 3 h than that at 2 h indicating thatwith the increase in reaction time more tar would beproduced 1us the optimum reaction time was 2 h

324 Influence of Catalyst Dosage Table 5 shows the effectof Fe(II)MOF-5 catalyst consumption of 3 on the hy-droxylation of phenol With the increase in catalyst con-sumption the yield of dihydroxybenzene first increased andthen decreased but the yield decreased at the mass ratio ofcatalyst to phenol above 008 1is was because an excess ofcatalyst accelerated the decomposition of H2O2 and reducedthe utilization rate of H2O2 1e catalyst-to-phenol massratio of 0053 was optimal

33 Catalyst Stability We did a blank experiment that onlyadded catalyst water and hydrogen peroxide to test thestability of catalyst under reaction conditions 1e reactionwas as follows 10 g of Fe(II)MOF-5 (3 Fe2+) was placed in160mL of hydrogen peroxide (30) and 300mL of deionizedwater at 80degC with stirred for 1 h 15 h and 2 h respectivelyAfter filtered they were vacuum dried at 80degC for 2 h 1eXRD of the samples is respectively shown in Figure 11

Compared with the Fe(II)MOF-5 without the stabilitytest the feature peaks of the stability test Fe(II)MOF-5

Table 2 Catalytic experimental results of phenol hydroxylation

Catalyst Content of Fe2+

(mass )Catechol yield

(mass )Hydroquinone yield

(mass )Dihydroxy benzeneyield (mass )

Catechol selectivity(mass )

Fe(II)MOF-5

0 mdash mdash mdash mdash1 242 26 278 862 423 12 435 9593 532 mdash 532 9864 40 mdash 40 9745 233 mdash 233 9566 151 mdash 151 962

Reaction conditions reaction temperature 80degC reaction time 2 h catalyst-to-phenol mass ratio 0053

225200175150125100075050025000

350 375 400 425 450 475 500 525 600 625 650 675 700 725550 575

121

04

223

90

TIC

OH

OHOH

Figure 8 GC-MS test of phenol hydroxylation over Fe(II)MOF-5 (3)

O-H O-H O-H O-H O-H

H-O H-O H-O H-O H-O

n

Figure 9 Multimolecule association of hydrogen bonds amonghydroxyls of hydroquinone to form hydroquinone


around 7deg disappeared and the characteristic peak around10deg slightly moved to left but the feature peaks of 13deg and 14degstill keep 1is may be because MOF-5 interacts with water

molecules causing partial phase transitions However wefound that the XRD peak shape of the catalysts did notchange during different test periods (1 h 15 h and 2 h) afterthe initial partial phase transitions 1is indicates that thecatalyst structure will remain stable in the reaction after theinitial change

Iron leaching is a serious problem for many iron-con-taining mesoporous and microporous materials In order tocheck the leaching of the catalysts after the reaction a smallamount of reaction liquid was taken out for filtration andthen the concentration of iron ions was measured by atomicabsorption spectroscope 1e leached iron ions ratio is cal-culated according to its concentration in reaction liquid Wefound that the leached iron ions rates of are 18 after reactionIn addition to the natural leaching of iron ions the reason forthe high iron ion leaching is the structural change of MOF-5

34 Hot Filtration Test We also did the hot filtration test ofthe reaction After reaction for one hour the reaction liquid

Table 3 Effect of reaction temperature on phenol hydroxylation

Temperature (degC) CAT (mass ) HQ yield (mass ) Dihydroxybenzene yield (mass ) CAT selectivity (mass )50 0 0 0 060 0 0 0 070 42 64 484 85480 532 0 532 986

Table 4 Effect of reaction time on the phenol hydroxylation

Reaction time (h) Catechol yield(mass )

Hydroquinone yield(mass )

Dihydroxybenzene yield(mass )


05 0 0 0 01 36 0 36 1002 532 0 532 9863 487 0 487 95

Reactiontime 2h

Reactiontime 3h

Figure 10 Color contrast diagram of reaction solution with different reaction times

Table 5 Effect of catalyst dosage on the phenol hydroxylation

Ratio of catalyst tophenol (mass )

Catechol yield(mass )

Hydroquinoneyield (mass )

Dihydroxybenzeneyield (mass ) Catechol selectivity (mass )

0027 414 62 476 8470053 532 0 532 986008 45 0 45 9730107 262 0 262 974

Stability test for 2hr



Fe(II)MOF-5 (3 Fe2+)

10 20 30 40 502-theta (deg)

Inte

nsity

(cou

nts)

Figure 11 XRD contrast chart of Fe(II)MOF-5 (3 Fe2+) beforeand after the stability test


is removed and filtered out of the catalyst then the filtrate iscontinued to react under the same conditions for one hourContent of products before and after filtration was analyzedby GC It was found that the catechol yield after filtration wasalmost the same as that before filtration 1is indicates thatalthough a small amount of iron ions was leached in thereaction process there was no catalytic activity afterfiltration

4 Conclusion

Fe(II)MOF-5 catalysts were prepared by equivalent loadingat low temperature XRD analysis showed that the additionof Fe ions had little effect on the crystal structure of MOF-51e results of test by EDS (energy dispersive spectrometry)showed that Fe was indeed loaded to the samples 1echaracterization by TEM and BETshowed that Fe(II)MOF-5 had a very regular pore structure like MOF-5 and the poresize was about 12 nm It was found from phenol hydrox-ylation catalyzed by Fe(II)MOF-5 that Fe2+-supportedMOF-5 could provide high catalytic activity and catecholselectivity for phenol hydroxylation 1e yield of dihy-droxybenzene was 532 and the selectivity of catechol was986 at the Fe2+ content of 3wt reaction temperature of80degC reaction time of 2 h and catalyst-to-phenol mass ratioof 0053

Data Availability

No data were used to support this study

Conflicts of Interest

1e authors declare that there are no conflicts of interestregarding the publication of this article

Acknowledgments

1is study was supported by the Key RampD Projects of Hunanscience and Technology (2017GK2020) the Key Laboratoryof Green Catalysis and Reaction Engineering in Hunan HighUniversities the Hunan 2011 Collaborative InnovationCenter of Chemical Engineering Technology with Envi-ronmental Benignity and Effective Resource Utilization theHunan Key Laboratory of Chemical Process Integration andOptimization the National amp Local United EngineeringResearch Centre for Chemical Process Integration theConstruct Program of the Key Discipline in HuaihuaUniversity and the Huaihua University Science ResearchProject (HHUY2019-17) Also the authors thank the HunanEngineering Laboratory for Preparation Technology ofPolyvinyl Alcohol (PVA) Fiber Material

References

[1] H Zhang C Tang Y Lv et al ldquoSynthesis characterizationand catalytic performance of copper-containing SBA-15 in thephenol hydroxylationrdquo Journal of Colloid and Interface Sci-ence vol 380 no 1 pp 16ndash24 2012

[2] X Gao and X Lu ldquoResearch progress on catalysts for hy-droxylation of phenol to dihydroxybenzenrdquo Chemical Re-agents vol 31 no 7 pp 519ndash530 2009

[3] H Shao X Chen B Wang J Zhong and C Yang ldquoSynthesisand catalytic properties of MeAPO-11 molecular sieves forphenol hydroxylationrdquo Acta Petrolei Sinica vol 28 no 6pp 933ndash939 2012

[4] Y Zhao G He W Dai and H Chen ldquoHigh catalytic activityin the phenol hydroxylation of magnetically separableCuFe2O4-reduced graphene oxiderdquo Industrial amp EngineeringChemistry Research vol 53 no 32 pp 12566ndash12574 2014

[5] S Shu and S Zhang ldquoDevelopment of catalysts for hy-droxylation of phenol to dihydroxybenzene by hydrogenperoxiderdquo Chemistry Bulletin vol 78 no 8 pp 702ndash7092015

[6] H Belarbi Z Lounis A Bengueddach and P Trens ldquoIn-fluence of the particle size of Cu-ZSM-5 for the heterogeneousoxidation of bulky hydrocarbonsrdquo e European PhysicalJournal Special Topics vol 224 no 9 pp 1963ndash1976 2015

[7] I Fatimah ldquoPreparation of ZrO2Al2O3-montmorillonitecomposite as catalyst for phenol hydroxylationrdquo Journal ofAdvanced Research vol 5 no 6 pp 663ndash670 2014

[8] B P Nethravathi K Ramakrishna Reddy andK N Mahendra ldquoCatalytic activity of supported solid cata-lysts for phenol hydroxylationrdquo Journal of Porous Materialsvol 21 no 3 pp 285ndash291 2014

[9] H Li M Eddaoudi M OrsquoKeeffe and O M Yaghi ldquoDesignand synthesis of an exceptionally stable and highly porousmetal-organic frameworkrdquo Nature vol 402 no 6759pp 276ndash279 1999

[10] Y Zhao ldquoPreparation and catalytic performance for phenolhydroxylation of Fe-SBA-16 mesoporous molecular sievesrdquoChemical Industry and Engineering Progress vol 35 no 2pp 187ndash191 2016

[11] T Yu S Q Zhang C M Ding and Z B Zhao ldquoStudy onhighly selective hydroxylation of phenol in the aqueousphaserdquo Chemistry Bulletin vol 78 no 4 p 364 2015

[12] W Zhang Y Wang Y Shen M Xie and X Guo ldquoMeso-porous zinc aluminate (ZnAl2O4) nanocrystal synthesisstructural characterization and catalytic performance towardsphenol hydroxylationrdquo Microporous and Mesoporous Mate-rials vol 226 pp 278ndash283 2016

[13] F Adam J-T Wong and E-P Ng ldquoFast catalytic oxidationof phenol over ironmodified zeolite L nanocrystalsrdquoChemicalEngineering Journal vol 214 no 1 pp 63ndash67 2013

[14] Y Q Zheng W B Tao and K H Ding ldquoSynthesis andcatalytic properties of catalyst Cd-MOF-cat for selective ox-idation of phenol to hydroquinonerdquo Industrial Catalysisvol 22 no 4 p 287 2014

[15] Y C Hu ldquoSynthesis of hydroquinone by phenol hydroxyl-ation over as-Mo-V heleropoly salt catalystrdquo Journal of Pet-rochemical Universities vol 18 no 1 pp 11ndash13 2005

[16] Y Zhan L Shen C XuW Zhao Y Cao and L Jiang ldquoMOF-derived porous Fe2O3 with controllable shapes and improvedcatalytic activities in H2S selective oxidationrdquo Crys-tEngComm vol 20 no 25 pp 3449ndash3454 2018

[17] S Bhattacharjee Y-R Lee P Puthiaraj S-M Cho andW-S Ahn ldquoMetal-organic frameworks for catalysisrdquo Ca-talysis Surveys from Asia vol 19 no 4 pp 203ndash222 2015

[18] J Kim S-H Kim S-T Yang and W-S Ahn ldquoBench-scalepreparation of Cu3(BTC)2 by ethanol reflux synthesis op-timization and adsorptioncatalytic applicationsrdquo Micro-porous and Mesoporous Materials vol 161 no 5 pp 48ndash552012


[19] J Kim S Bhattacharjee K-E Jeong S-Y Jeong andW-S Ahn ldquoSelective oxidation of tetralin over a chromiumterephthalate metal organic framework MIL-101rdquo ChemicalCommunications vol 26 no 26 p 3904 2009

[20] S Bhattacharjee J-S Choi S-T Yang S B Choi J Kim andW-S Ahn ldquoSolvothermal synthesis of Fe-MOF-74 and itscatalytic properties in phenol hydroxylationrdquo Journal ofNanoscience and Nanotechnology vol 10 no 1 pp 135ndash1412010

[21] S-N Kim J Kim H-Y Kim H-Y Cho and W-S AhnldquoAdsorptioncatalytic properties of MIL-125 and NH2-MIL-125rdquo Catalysis Today vol 204 no 1 pp 85ndash93 2013

[22] Y-R Lee S-M Cho W-S Ahn C-H Lee K-H Lee andW-S Cho ldquoFacile synthesis of an IRMOF-3 membrane onporous Al2O3 substrate via a sonochemical routerdquo Micro-porous and Mesoporous Materials vol 213 no 1 pp 161ndash1682015

[23] M Faustini J Kim G-Y Jeong et al ldquoMicrofluidic approachtoward continuous and ultrafast synthesis of metal-organicframework crystals and hetero structures in confinedmicrodropletsrdquo Journal of the American Chemical Societyvol 135 no 39 pp 14619ndash14626 2013

[24] N R Shiju A H Alberts S Khalid D R Brown andG Rothenberg ldquoMesoporous silica with site-isolated amineand phosphotungstic acid groups a solid catalyst with tunableantagonistic functions for one-pot tandem reactionsrdquoAngewandte Chemie vol 123 no 41 pp 9789ndash9793 2011

[25] Y-M Chung H-Y Kim and W-S Ahn ldquoFriedel-craftsacylation of p-xylene over sulfonated zirconium terephthal-atesrdquo Catalysis Letters vol 144 no 5 pp 817ndash824 2014

[26] J Kim S-N Kim H-G Jang G Seo and W-S Ahn ldquoCO2cycloaddition of styrene oxide over MOF catalystsrdquo AppliedCatalysis A General vol 453 no 6 pp 175ndash180 2013

[27] S Bhattacharjee and W-S Ahn ldquoPalladium nanoparticlessupported on MIL-101 as a recyclable catalyst in water-me-diated Heck reactionrdquo Journal of Nanoscience and Nano-technology vol 15 no 9 pp 6856ndash6859 2015

[28] S Bhattacharjee Y-R Lee and W-S Ahn ldquoPost-synthesisfunctionalization of a zeolitic imidazolate structure ZIF-90 astudy on removal of Hg(II) from water and epoxidation ofalkenesrdquo CrystEngComm vol 17 no 12 pp 2575ndash2582 2015

[29] X Chen Y Hou H Wang Y Cao and J He ldquoFacile de-position of Pd nanoparticles on carbon nanotube micro-particles and their catalytic activity for suzuki couplingreactionsrdquo e Journal of Physical Chemistry C vol 112no 22 pp 8172ndash8176 2008

[30] S S Kaye A Dailly O M Yaghi and J R Long ldquoImpact ofpreparation and handling on the hydrogen storage propertiesof Zn4O(14-benzenedicarboxylate)3(MOF-5)rdquo Journal of theAmerican Chemical Society vol 129 no 46 pp 14176-141772007

[31] E V Perez K J Balkus J P Ferraris and I H MusselmanldquoMixed-matrix membranes containing MOF-5 for gas sepa-rationsrdquo Journal of Membrane Science vol 328 no 1-2pp 165ndash173 2009

[32] S Horike M Dinca K Tamaki and J R Long ldquoSize-selectivelewis acid catalysis in a microporous metal-organic frame-work with exposed Mn2+ coordination sitesrdquo Journal of theAmerican Chemical Society vol 130 no 18 pp 5854-58552008

[33] U Ravon M E Domine C Gaudillere A Desmartin-Chomel and D Farrusseng ldquoMOF-5 as acid catalyst withshape selectivity propertiesrdquo in Proceedings of the 4th

International FEZA Conference vol 174 no 8 pp 467ndash470Paris France September 2008

[34] W Zhang G Lu C Cui et al ldquoA family of metal-organicframeworks exhibiting size-selective catalysis with encapsu-lated noble-metal nanoparticlesrdquo Advanced Materials vol 26no 24 pp 4056ndash4060 2014

[35] C-H Kuo Y Tang L-Y Chou et al ldquoYolk-shell nano-crystalZIF-8 nanostructures for gas-phase heterogeneouscatalysis with selectivity controlrdquo Journal of the AmericanChemical Society vol 134 no 35 pp 14345ndash14348 2012

[36] M Muller S Turner O I Lebedev Y WangG van Tendeloo and R A Fischer ldquoAuMOF-5 and AuMOxMOF-5 (MZn Ti x 1 2) preparation and mi-crostructural characterisationrdquo European Journal of InorganicChemistry vol 2011 no 12 pp 1876ndash1887 2011

[37] L Ning S Liao H Cui L Yu and X Tong ldquoSelectiveconversion of renewable furfural with ethanol to producefuran-2-acrolein mediated by PtMOF-5rdquo ACS SustainableChemistry amp Engineering vol 6 no 1 pp 135ndash142 2017

[38] F Xamena A Abad A Corma and H Garcia ldquoMOFs ascatalysts activity reusability and shape-selectivity of a Pd-containing MOFrdquo Journal of Catalysis vol 250 no 2pp 294ndash298 2007

[39] M Zhang F X Yin X B He and G R Li ldquoPreparation ofNiCo-MOF-74 and its electrocatalytic oxygen precipitationperformancerdquo Journal of Beijing University of ChemicalTechnology (Natural Science) vol 46 no 4 pp 38ndash45 2019

[40] L Liu X Tai M Liu Y Li Y Feng and X Sun ldquoSupportedAuMOF-5 a highly active catalyst for three-componentcoupling reactionsrdquo CIESC Journal vol 66 no 5 pp 1738ndash1747 2015

[41] Restu Kartiko Widi et al ldquoHydroxylation of phenol withhydrogen peroxide catalyzed by Fe- and AIFe-bentoniterdquoChemistry and Chemical Engineering English Version vol 3no 4 pp 48ndash52 2009

[42] M E L Preethi S Revathi T Sivakumar et al ldquoPhenolhydroxylation using FeAl-MCM-41 catalystsrdquo CatalysisLetters vol 120 no 1-2 pp 56ndash64 2008

[43] M S Hamdy G Mul W Wei et al ldquoFe Co and Cu-in-corporated TUD-1 synthesis characterization and catalyticperformance in N2O decomposition and cyclohexane oxi-dationrdquo Catalysis Today vol 110 no 3-4 pp 264ndash271 2005

[44] M N Cele H B Friedrich andM D Bala ldquoA study of Fe(III)TPPCl encapsulated in zeolite NaY and Fe(III)NaY in theoxidation of n-octane cyclohexane 1-octene and 4-octenerdquoReaction Kinetics Mechanisms and Catalysis vol 111 no 2pp 737ndash750 2014

[45] S X Gao N Zhao M H Shu and S N Che ldquoPalladiumnanoparticles supported on MOF-5 a highly active catalystfor a ligand- and copper- free sonogashira coupling reactionrdquoApplied Catalysis A General vol 388 no 1-2 pp 196ndash2012010

[46] N Zhao H P Deng and M H Shu ldquoPreparation andcatalytic performance of Pd catalyst supported on MOF-5rdquoChinese Journal of Inorganic Chemistry vol 26 no 7pp 1213ndash1217 2010

[47] Z Zhao Z Li and Y S L Jerry ldquoSecondary growth synthesisof MOF-5 membranes by dip-coating nano-sized MOF-5seedsrdquo CIESC Journal vol 62 no 2 pp 507ndash514 2011

[48] H Shao X Chen B Wang J Zhong and C Yang ldquoSynthesisand catalytic properties of MeAPO-11 molecular sieves forphenol hydroxylationrdquo Acta Petrolei Sinica (Petroleum Pro-cessing Section) vol 28 no 6 pp 933ndash939 2012


[49] G Wang X Wang Y Zhang et al ldquoEffect of hydrogen bondson the static effect of nanofiltration processrdquo Journal ofMaterials Science amp Engineering vol 27 no 4 pp 610ndash6122009

[50] X Zhang J Zhang G Zhang et al ldquoFormation and inhibitionof phenolic tars in process for preparation of diphenols by thehydroxylatuion of phenolrdquo Journal of Chemical Engineering ofChinese Universities vol 21 no 2 pp 257ndash261 2007

[51] B-L Xiang L Fu Y Li and Y Liu ldquoA new Fe(III)MOF-5(Ni) catalyst for highly selective synthesis of catechol fromphenol and hydrogen peroxiderdquo ChemistrySelect vol 4 no 4pp 1502ndash1509 2019

[52] S Buttha S Youngme J Wittayakun and S Loiha ldquoFor-mation of iron active species on HZSM-5 catalysts by varyingiron precursors for phenol hydroxylationrdquo Molecular Ca-talysis vol 461 no 26 pp 2468ndash8231 2018


TribologyAdvances in

Hindawiwwwhindawicom Volume 2018


International Journal ofInternational Journal ofPhotoenergy


Journal of

Chemistry


Advances inPhysical Chemistry

Hindawiwwwhindawicom

Analytical Methods in Chemistry

Journal of

Volume 2018

Bioinorganic Chemistry and ApplicationsHindawiwwwhindawicom Volume 2018

SpectroscopyInternational Journal of


Hindawi Publishing Corporation httpwwwhindawicom Volume 2013Hindawiwwwhindawicom

The Scientific World Journal

Volume 2018

Medicinal ChemistryInternational Journal of


NanotechnologyHindawiwwwhindawicom Volume 2018

Journal of

Applied ChemistryJournal of



Biochemistry Research International


Enzyme Research


Journal of

SpectroscopyAnalytical ChemistryInternational Journal of


MaterialsJournal of



BioMed Research International Electrochemistry

International Journal of


Na

nom

ate

ria

ls


Journal ofNanomaterials

Submit your manuscripts atwwwhindawicom

solvent with the catechol selectivity of 873 but the phenolconversion was only 1711erefore it is very important todevelop a catalyst with high phenol conversion and catecholselectivity

Metal-organic frameworks (MOFs) are new nano-porous frameworks with periodic network structureformed by self-assembling of nitrogen or oxygen-con-taining organic ligands and transition metal ions throughcomplexation [16] MOFs have well-ordered tunable po-rous structures with a wide range of pore sizes and ex-ceptional textural properties of high surface areas and highpore volumes which can afford a variety of applications ingas adsorptionseparation and heterogeneous catalysis[17] When MOFs is used as a homogeneous catalyst it hasbeen used for the following reactions (a) aerobic oxidationof tetralin [18 19] (b) phenol hydroxylation [20] (c)oxidative desulfurization of dibenzothiophene [21] (d)Knoevenagel condensation reaction [22 23] (e) one potdeacetalization-nitroaldol reaction [24] (f ) FriedelndashCraftacylation [25] (g) CO2 cycloaddition of epoxides [26] (h)heck reaction [27] and (i) epoxidation of alkenes [28] As atypical representative of the metal-organic frameworkcomplex family MOF-5 was a framework with a three-dimensional structure high specific surface and well-de-fined pore structure formed by connecting an inorganicgroup [Zn4O] consisting of four zinc and one O toP-phenylene dimethyl [29] It has much higher specificsurface and pore volume than activated carbon zeolitemolecular sieves and silica Kaye et al in Yaghi team [30]reported a MOF-5 with the specific surface area of 2900m2g Perez et al [31] reported a MOF-5 with the specificsurface area of 3362m2g MOF-5 has a shape-selectiveeffect in specific catalytic reactions because of its con-trollable pore size and orderly pore size [32ndash35] which ishelpful to improve the selectivity of the reactions MOF-5was also often used as a carrier to support different catalyticactive sites such as Pt Au and Pd to prepare MOF-basedcatalysts [36ndash39] for different heterogeneous catalytic re-actions with good catalytic effect For example Liu et al[40] have reported the catalyst AuMOF-5 which supportedAu on a functionalized MOF-5 by the impregnationmethod 1e results showed that the AuMOF-5 catalystdisplayed high activity and 100 selectivity forpropargylamines

In addition many transition metals such as Cu MnMo and Fe have the activity to catalyze phenol hydrox-ylation but Fe-supported catalysts are used more fre-quently For example the Fe-supported bentonite catalystprepared by RESTU [41] and FeAl-MCM-41 prepared byPreethi et al [42] show better catalytic activity thanother transition metals Also some Fe-supported catalystsshowed good selectivity in some oxidation reactions[43 44]

In this paper Fe2+-supportedMOF-5 was synthesized bythe direct precipitation method and used for phenol hy-droxylation MOF-5 cannot withstand high temperatureabove 400degC [45] so Fe(II)MOF-5 was prepared by

equivalent loading of Fe2+ at low temperature [46] and usedto catalyze hydroxylation of phenol by hydrogen peroxide inorder to study the performance of the Fe(II)MOF-5 catalystand technological conditions of hydroxylation of phenol byhydrogen peroxide

2 Experimental

21 Reagents and Apparatuses All chemicals in this studywere directly used without any purification Zn(NO3)2middot6H2O terephthalicacid DMF(NN-dimethylformamide)triethylamine FeSO4middot7H2O phenol hydrogen peroxide(30) deionized water and ethyl acetate are all chemicallypure

A 3-mouth flask EL204 analytical balance round-bot-tom flask beaker funnel DF-101S constant temperaturemagnetic stirrer liquid separating funnel gas chromatog-raphy-mass spectrometry were used (Shimadzu GCMS2010-plus)

22 Direct Precipitation Synthesis of MOF-5 3 g ofZn(NO3)2middot6H2O and 1275 g of di-2-hydroxyethyl tere-phthalate were weighed to three flasks 100mL of DMF wasadded1emixture was well mixed at room temperature untila clear solution was obtained Triethylamine (4 g 55mL) wasdropwise added under violent agitation 1e solution grad-ually became turbid After that the solution was stirred for 3 hand filtered at vacuum 1e cake was washed with DMF(3times 20mL) and dried at 120degC to form MOF-5 [46]

23 Preparation of Fe(II)MOF-5 by the Equivalent LoadingMethod Based on 5 g of MOF-5 the mass of FeSO4middot7H2Owas calculated according to the Fe2+ loading of 1 2 34 5 6 and 7 (wt) respectively FeSO4middot7H2O wasweighed to a conical bottle containing DMF (the volume ofDMF was equal to that of 5 g of MOF-5) and dissolved underagitation at room temperature 5 g of MOF-5 was added tothe solution Meanwhile MOF-5 was just immersed in DMFsolution1e solution was well mixed and dried at vacuum at90degC for 2 h to obtain Fe(II)MOF-5 with the Fe2+ loading of1 2 3 4 5 6 and 7

24 Hydroxylation of Phenol 05 g of Fe(II)MOF-5 90mLof phenol 160mL of hydrogen peroxide (30) and 300mLof deionized water were taken to a round-bottom flaskwhere the reaction lasted for 1sim3 h under magnetic agitationat 80degC At the end of the reaction the solution was filtrated1e filtrate was extracted by ethyl acetate three times 1eextract was tested on phenol and dihydroxybenzene contentsby gas chromatography-mass spectrometry (GCMS 2010-plus) 1e filtrate was distilled to remove all liquids andobtain a small amount of solid (tar) on the flask wall 1e tarwas weighed 1e yield of catechol hydroquinone benzo-diazepine and the selectivity of catechol were calculated bythe following formula



mphenol

SCAT 94mCAT



SHQ 94mHQ


YDHB YCAT + YHQ


(1)











Fe(II)MOF-5

6 Fe2+

5 Fe2+

4 Fe2+

3 Fe2+

2 Fe2+

1 Fe2+

0 Fe2+

2-theta (deg)

Inte

nsity

(cou

nts)

10 20 30 40 50 60









(b)(a)


0 1 2 3 4 5 kev

200μm




Tran

smitt

ance

Fe(II)MOF-5

6 Fe2+

5 Fe2+

4 Fe2+3 Fe2+2 Fe2+

1 Fe2+

0 Fe2+








C O

Zn Fe


(a) (b)




00000

00005

00010

00015

00020

00025

00030

00035

00040

00045

dVp

drp

100101rp (nm)

















Fe(II)MOF-5



225200175150125100075050025000

350 375 400 425 450 475 500 525 600 625 650 675 700 725550 575

121

04

223

90

TIC

OH

OHOH


O-H O-H O-H O-H O-H

H-O H-O H-O H-O H-O

n














05 0 0 0 01 36 0 36 1002 532 0 532 9863 487 0 487 95

Reactiontime 2h

Reactiontime 3h







0027 414 62 476 8470053 532 0 532 986008 45 0 45 9730107 262 0 262 974





10 20 30 40 502-theta (deg)

Inte

nsity

(cou

nts)




4 Conclusion


Data Availability




Acknowledgments


References






























































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls





mphenol

SCAT 94mCAT



SHQ 94mHQ


YDHB YCAT + YHQ


(1)











Fe(II)MOF-5

6 Fe2+

5 Fe2+

4 Fe2+

3 Fe2+

2 Fe2+

1 Fe2+

0 Fe2+

2-theta (deg)

Inte

nsity

(cou

nts)

10 20 30 40 50 60









(b)(a)


0 1 2 3 4 5 kev

200μm




Tran

smitt

ance

Fe(II)MOF-5

6 Fe2+

5 Fe2+

4 Fe2+3 Fe2+2 Fe2+

1 Fe2+

0 Fe2+








C O

Zn Fe


(a) (b)




00000

00005

00010

00015

00020

00025

00030

00035

00040

00045

dVp

drp

100101rp (nm)

















Fe(II)MOF-5



225200175150125100075050025000

350 375 400 425 450 475 500 525 600 625 650 675 700 725550 575

121

04

223

90

TIC

OH

OHOH


O-H O-H O-H O-H O-H

H-O H-O H-O H-O H-O

n














05 0 0 0 01 36 0 36 1002 532 0 532 9863 487 0 487 95

Reactiontime 2h

Reactiontime 3h







0027 414 62 476 8470053 532 0 532 986008 45 0 45 9730107 262 0 262 974





10 20 30 40 502-theta (deg)

Inte

nsity

(cou

nts)




4 Conclusion


Data Availability




Acknowledgments


References






























































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls










(b)(a)


0 1 2 3 4 5 kev

200μm




Tran

smitt

ance

Fe(II)MOF-5

6 Fe2+

5 Fe2+

4 Fe2+3 Fe2+2 Fe2+

1 Fe2+

0 Fe2+








C O

Zn Fe


(a) (b)




00000

00005

00010

00015

00020

00025

00030

00035

00040

00045

dVp

drp

100101rp (nm)

















Fe(II)MOF-5



225200175150125100075050025000

350 375 400 425 450 475 500 525 600 625 650 675 700 725550 575

121

04

223

90

TIC

OH

OHOH


O-H O-H O-H O-H O-H

H-O H-O H-O H-O H-O

n














05 0 0 0 01 36 0 36 1002 532 0 532 9863 487 0 487 95

Reactiontime 2h

Reactiontime 3h







0027 414 62 476 8470053 532 0 532 986008 45 0 45 9730107 262 0 262 974





10 20 30 40 502-theta (deg)

Inte

nsity

(cou

nts)




4 Conclusion


Data Availability




Acknowledgments


References






























































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls








C O

Zn Fe


(a) (b)




00000

00005

00010

00015

00020

00025

00030

00035

00040

00045

dVp

drp

100101rp (nm)

















Fe(II)MOF-5



225200175150125100075050025000

350 375 400 425 450 475 500 525 600 625 650 675 700 725550 575

121

04

223

90

TIC

OH

OHOH


O-H O-H O-H O-H O-H

H-O H-O H-O H-O H-O

n














05 0 0 0 01 36 0 36 1002 532 0 532 9863 487 0 487 95

Reactiontime 2h

Reactiontime 3h







0027 414 62 476 8470053 532 0 532 986008 45 0 45 9730107 262 0 262 974





10 20 30 40 502-theta (deg)

Inte

nsity

(cou

nts)




4 Conclusion


Data Availability




Acknowledgments


References






























































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls


















Fe(II)MOF-5



225200175150125100075050025000

350 375 400 425 450 475 500 525 600 625 650 675 700 725550 575

121

04

223

90

TIC

OH

OHOH


O-H O-H O-H O-H O-H

H-O H-O H-O H-O H-O

n














05 0 0 0 01 36 0 36 1002 532 0 532 9863 487 0 487 95

Reactiontime 2h

Reactiontime 3h







0027 414 62 476 8470053 532 0 532 986008 45 0 45 9730107 262 0 262 974





10 20 30 40 502-theta (deg)

Inte

nsity

(cou

nts)




4 Conclusion


Data Availability




Acknowledgments


References






























































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls















05 0 0 0 01 36 0 36 1002 532 0 532 9863 487 0 487 95

Reactiontime 2h

Reactiontime 3h







0027 414 62 476 8470053 532 0 532 986008 45 0 45 9730107 262 0 262 974





10 20 30 40 502-theta (deg)

Inte

nsity

(cou

nts)




4 Conclusion


Data Availability




Acknowledgments


References






























































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls





4 Conclusion


Data Availability




Acknowledgments


References






























































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls














































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls




PreparationofFe(II)/MOF-5CatalystforHighlySelective ... · 2019. 11. 7. · A 3-mouth ﬂask, EL204...

Documents

Transcript of PreparationofFe(II)/MOF-5CatalystforHighlySelective ... · 2019. 11. 7. · A 3-mouth ﬂask, EL204...