Catalysts for glycerol hydrogenolysis

Catalysts for glycerol hydrogenolysis:
production of glycols from biomass derivatives
Daniela Zanchet
Instituto de Química, UNICAMP, Campinas, SP
daniela@iqm.unicamp.br
2007/51754-4 - PITE project as part of FAPESP-OXITENO and BIOEN initiative
Term: 10/2008-03/2011
Team
LNLS-CNPEM (ABTLuS)
Oxiteno Ind. & Com. Ltda
Dr. Cristiane B. Rodella
Dr. Valéria P. Vicentini
Dr. Silvia Fernanda Moya
Ms. Carla M. S. Queiroz
Dr. Ricardo J. Chimentão
Lígia S.Rodrigues (tech. – TT2)
Rafael A. Ferreira (tech. - TT2)
Collaborators
Dr. Roberto Rinaldi (Max-Planck)
Prof. Victor Teixeira (UFRJ)
Goal
Glycerol  major by-product of biodiesel production (low cost, large
volume) . New opportunites (“glycerochemistry”)
Glycerol Hydrogenolysis
H2
H2
Goal
Evaluation and development of heterogeneous catalysts
(industrial application at OXITENO);
Understanding of the kinetics and mechanism of the catalytic
hydrogenolysis - Selectivity to EG or 1,2-PG
Correlation with physical and chemical properties of the catalysts
Model catalysts based on nanoscience approach
Scientific challenges
Glycerol hydrogenolysis is a complex chemical reaction →
parallel pathways and reactions (reforming, WGS, methanation)
-H2O
H
+H2
H
A. Torres et al., Ind. Eng. Chem. Res. , 2010; C.J. Mota et al. Quimica Nova, 2009.
Coupled reactions
Reforming+ hydrogenolysis
Roy et al, Cat. Today, 156 (2010), 31; Yin et al., Green Chem., 11 (2009), 1514.
Scientific challenges
For the reaction:
Coupled reactions - maximize activity and selectivity to either EG
and 1,2-PG; minimize the formation of gas products (conc., T, P)
For the catalyst:
Tuning catalysts properties (electronic configuration, particle size,
defects, metal dispersion, etc.): active sites that enhance different
type of bond cleavage: C-C, C-O, C-H, O-H
Keeping in mind… to find the best compromise considering the
specific needs of OXITENO
Infrastructure at LSQ-LNLS
High pressure reactor installed in an explosionproof room – similar to OXITENO set-up
Gas
chromatograph
Fixed bed reactor set-up
Integration and
automation of reactor
operation software and
safety interlocks
Catalysts
Catalysts development and testing:
Conventional catalyst: Ru/C best catalyst to promote C-C cleavage,
but high cost and severe catalytic reaction conditions
Alternatives :
•Ni Raney  low cost and mild catalytic reaction condition (no need
of external H2)
• Tungsten carbides supported on carbon  platinum-like catalytic
behavior, efficient for cellulose hydrogenolysis, low cost but severe
catalytic reaction conditions
•Model catalysts based on colloidal nanoparticles
5% Ru/C
Samples:
5% Ru/C (Acros)
5% Ru/C – LNLS (dry impregnation RuCl3)
1wt.% glycerol, 110 mg of catalyst, 4MPa of H2
Raney Ni catalyst
Raney Ni
Ni-Al alloy
Al
Ni2Al3
NiAl3
Samples:
Raney Ni 3111A - Grace Co. (1% Mo)
Raney Ni 2800 - Grace Co.
Raney Ni - LNLS
10wt.% glycerol, 1,67g of catalyst
C.B. Rodella, G. Kellermann, M.S.P. Francisco, M.H. Jordão, D. Zanchet, Ind. Eng. Chem. Res. 2008, 47, 8612.
Raney Ni x Ru/C
Both produce large amounts of gas (CO2, CH4)
Raney Ni →1,2-PG
Ru/C → EG
H2 pressure favors EG. Raney Ni favors the reforming
of glycerol
Selectivity to EG decreases with time
Degradation of EG is more pronounced in Ru/C
The results pointed out that high selectivity to EG will
be difficult to be achieved in batch reactor
(Temperature transient at the beginning).
Carbon support
Dependence on the carbon support supplier
Ru/C
C-A
C-B
C-MERCK
26,0
23,7
30,7
EG
19,4
29,6
27,2
1,2-PG
13,5
15,3
11,9
CO2
1,6
0,4
-
CH4
59,1
43,5
48,4
Others
6,4
11,2
13,5
Selectivity to liq. (%)
34,0
50,2
44,1
Conversion (%)
Selectivity
(%)
*All samples presented traces of acetol .
P.Trecco (Undergraduate project)
Tungsten Carbides -Synthesis
Improves
surface area
Temperature Programmed Carburization (TCP)
WO3  WOx (0x3)  W  W2C  WC
100 – 200 ml.min-1 pure H2
or 10%CH4/H2
W
amorphous
9000C
8500C
W2C
C
+
bcc
7000C
Temperature
WC
or
hcp
hex
Promoters like Ni, Fe and Co decrease carburization
temperature and improve catalytic activity
Structural characterization
XRD - in situ
Furnace
θ
X Ray beamline
WxC
Structural and surface properties - dependent on the gas used in
the carburization process and presence of Ni
H2 → well crystallized W2C, carbon deposition and low conversion
20%CH4/H2 → smaller particles, less carbon deposition and
higher conversion.
 Ni → carburization at lower temperature (100 K)
Glycerol hydrogenolysis favors 1,2-PG (acetol pathway).
Colloidal nanoparticles
Ru-NPs
NiPt-NPs
Preliminary results showed low activity in the hydrogenolysis of
propane
Collaboration with Dr. C.S. Claro and F. Requejo - Univ. La Plata, Argentina
Conclusion
Evaluation of catalysts for hydrogenolysis of glycerol:
EG is favored at short times. No satisfactory results were found
with batch reactor
 Selectivity to gas products excessively high.
Raney Ni - favors H* generation through glycerol reforming
Ru/C – higher selectivity to EG
WxC - carburization with CH4/H2 and presence of Ni improve the
performance. Selectivity towards 1,2-PG
Influence of the C support (?)
Other results: invited talk at CBCAT/11, CatBior/11, 2 articles in preparation
Acknowledgments
Dr. Cristiane Rodella (WxC - LNLS)
Dr. Silvia Moya (CTBE)
Dr. Ricardo Chimentão
Ligia Rodrigues
Rafael Ferreira
LNLS staff
Dr. Valéria Vicentini
Carla Queiroz
Oxiteno staff
Prof. Jose Maria C. Bueno
Debora M. Meira
Renata U. Ribeiro
Dr. Cecilia Claro (ULP)
Dr. Felix Requejo (ULP)
Dr. Roberto Rinaldi (Max-Planck)
Prof. Victor Teixeira (UFRJ)
Dr. Jose L. Zotin (CENPES)
Sandra Chiaro (CENPES)
Funding: FAPESP, Oxiteno, LNLS