Post on 24-Apr-2022
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
11
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
13
FDCA
Furanics for polymers US Department
of Energy biomass
14
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
15
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
16
Oxidation of HMF to FDCA
monometallic Au bimetallic Au-Cu
no activity for TiO2 and monometallic Cu
FDCA
yie
ld (m
ol %
)
PRIN08 project
17
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
19
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
22
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
23
- 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