Univ.of Messina and INSTM/CASPE, Italy

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Transcript of Univ.of Messina and INSTM/CASPE, Italy

European Research Institute of Catalysis

Univ.of Messina and INSTM/CASPE, Italy centi@unime.it

Italian Stakeholders Meeting on Biorefineries IEA BIOENERGY TASK 42, CHEMTEX (TORTONA), ITALY 4 APRIL

2

lignine

pretreatment/hydrolysis

(cellulose, hemicellulose) small oligomers (cellubiose,

cellutetrose, etc.) C5 and C6 sugars

water soluble

insoluble (biofuels ?)

alcohols (ethanol) + (2) CO2

fermentation

different paths for C5 and C6 ?

dehydration

s

APR

HC + nCO2

biofuels + chemicals

levulinic ac. + formic ac.

-CO2

GVL

biofuels & chemicals

biofuels & chemicals

(catalytic)

FURFURALS • Preserving molecule

integrity • Limit H2 consumption • Multiple use (functional

groups)

The lignocellulosic path

R = H, CH2OH

3

at high temp. (necessary for fast hydrolysis) the C5-C6 sugars are dehydrated to form furfural and hydroxy-methylfurfural (HMF), respectively these products inhibit enzymatic fermentation and it is more convenient their direct transformation to fuel and chemicals (with respect to fermentation to ethanol) compared to ethanol, 2,5-dimethylfuran has a higher energy density (by

40 %), a higher boiling point (by 20 K), and is not soluble in water

Biofine Process acid-catalyzed hydrolysis

Two-stage dilute acid hydrolysis 4

5

Centi et al., Catal Today (2010)

Furfurals as platform molecules

6

Upgrading of furfurals

Polymers

Biofuels

Fine chemicals

OOCH3

O

CHOO

O

OOH

O

HO

O

CH3CH2OH Acid catalyst

O2 Au - Au/Cu @TiO2

catalyst

CH3OH / O2 Au@ZrO2 catalyst

O

O

HHO

O

O

H

Upgrading of furfurals

HMF FA

PRIN08 project (ME, TO, VE, BO, CS)

Furanics for biofuels 7

CHOO

HO

CHOO

O

CHOO

434 K

564 K

Incr

easin

g bo

iling

poi

nt

Increasing oxygen content One Two Three Six

Pentose Xexose

HMF

2-FA

dehydration CH3CH2OH

catalyst

O

O

2,5-dimethylfuran (DMF)

2-methylfuran (2-MF)

366 K

336 K

RON = 131

RON = 119

H2 - catalytic hydrogenolysis

H2 - catalytic hydrogenolysis

Biodiesel

Octane booster for gasoline

2-ethoxy-5-methylfurfural (EMF)

Etherification of HMF 8

Experimental conditions: Autoclave autogenic pressure catalyst: 200 mg Reaction time: 5h T = 140°C (no HMF conversion for T < 140°C)

Mesoporous catalysts: SBA-15 MCM41

Microporous catalysts: ZSM5 Mordenite BEA MFI

Reference catalysts: H2SO4 Amberlyst®15

biodiesel components

9

0

10

20

30

40

50

60

70

80

90

100

EOP Yields

DE Yields

EMF Yields

Etherification of HMF on zeolysts

Temperature→ H2SO4 at 100°C give a last conversion of 5-HMF, no trace of desiderate products Acidity → key parameter in directing the reaction to the different products

5-HMF

EtOH + +

ethyl 4-oxopentanoate (EOP)

5-(ethoxymethyl)furan-2-carbaldeyde (EMF)

diethoxy ethane (DE)

10

Selectivity : 96%

BET surface area = 380 m2/g

HMF conversion 97 % 93 % 100 %

0102030405060708090

100

EOP Yields

DE Yields

EMF Yields

0

20

40

60

80

100

1 2 3 4 5

EM

F Yi

eld,

%

Reaction time, h

NH4+-BEA

SiO2/Al2O3 = 25

Etherification of 5-HMF on NH4+ zeolysts

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Etherification of HMF on mesoporous catalysts

Etherification of HMF: summary 12

High selectivity to EOP with H2SO4, Amberlyst®15 and Al-MCM-41(25) → strong Brønsted acidity that promotes the degradation of HMF to levulinic acid which is estherificated to EOP Strong Lewis acid sites are present, e.g. Z-SBA-15 (ZrO2 is

introduced) or Al-MCM-41 (50) (presence of extra-framework isolated Al3+ sites) → high selectivity to EMF

Weaker acidic catalysts, like Al-MCM-41(75) and pure SBA-15 form

DE as main product → DE deriving possibly from side reaction of ethanol

PRIN08 project

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FDCA

Furanics for polymers US Department

of Energy biomass

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Furanics for polymers

New polyesters and nylon with new properties likely for fiber applications Furanoic polyesters for bottles, containers, films Polyamide market for use in new nylon

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Furfurals to polymers

Low HMF yield High costs of catalysis Low catalysts stability

Au or Pt based catalysts / O2

Mordenite / aqueous CH2O

Furfural itself has a limited market (250,000 tons per year): is used primarily in the manufacture of furan resins, lubricating oils and textiles for leisure wear

literature data

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Oxidation of HMF to FDCA

monometallic Au bimetallic Au-Cu

no activity for TiO2 and monometallic Cu

FDCA

yie

ld (m

ol %

)

PRIN08 project

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Oxydation of HMF to FDCA

T = 95°C pO2 = 10 bar NaOH/HMF = 4

Proposed reaction pathway

Stability of the catalysts 18

Easy recovery of the catalysts Reuse of the catalyst without loss of

yield and selectivity to desiderate products

Low stability of the catalyst Formation of polymeric co-products Low yield in FDCA

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Furfurals to fine chemicals

FA MF

PRIN08 project

Effect of the calcination temperature on Au size 20

21

Effect of Au size on catalytic activity

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Furfurals An interesting platform molecule for a flexible use via

catalytic transformation • Biodiesel components by etherification with bioethanol • Monomers for high-performance polymers (by oxidat., reduction,

amination) • Valuable intermediates for fine and specialty chemicals

Preserve scheleton integrity (high C-efficiency), and minimize H2 consumption

It integrates in a more general biorefinery scheme

Conclusions

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- particle size reduct.(ca 0.5 to 1 cm)

- added dilute sulfuric acid (1.5–3).

- 1st reactor → acid hydrolysis polysaccharides to their soluble intermediates (e.g. HMF). plug-flow reactor, T = 210–220°C, P = 25 bar. τ =12 s

- 2nd reactor : CSTR, T =190–200°C, P = 14 bar, τ = 20 min

Purely chemical process (can be used a large variety of feedstocks) High temperature, fast (dilute) acid hydrolysis of biomass with 1-5% mineral acid in two reactors. The first reactor targets cellulose partial hydrolysis and conversion of hemicellulose pentoses to furfural. Second reactor, further hydrolysis and formation of HMF and then LA.

Biofine Process