Catalysts for glycerol hydrogenolysis: production of glycols from biomass derivatives
Daniela Zanchet Instituto de Química, UNICAMP, Campinas, SP
[email protected] 2007/51754-4 - PITE project as part of FAPESP-OXITENO and BIOEN initiative
Term: 10/2008-03/2011
LNLS-CNPEM (ABTLuS)
Dr. Cristiane B. Rodella
Dr. Silvia Fernanda Moya
Dr. Ricardo J. Chimentão
Lígia S.Rodrigues (tech. – TT2)
Rafael A. Ferreira (tech. - TT2)
Oxiteno Ind. & Com. Ltda
Dr. Valéria P. Vicentini
Ms. Carla M. S. Queiroz
Team
Collaborators
Dr. Roberto Rinaldi (Max-Planck)
Prof. Victor Teixeira (UFRJ)
Glycerol Hydrogenolysis
Glycerol major by-product of biodiesel production (low cost, large
volume) . New opportunites (“glycerochemistry”)
Goal
H2
H2
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
Goal
A. Torres et al., Ind. Eng. Chem. Res. , 2010; C.J. Mota et al. Quimica Nova, 2009.
+H2
-H2O
H
H
Scientific challenges Glycerol hydrogenolysis is a complex chemical reaction →
parallel pathways and reactions (reforming, WGS, methanation)
Coupled reactions Reforming+ hydrogenolysis
Roy et al, Cat. Today, 156 (2010), 31; Yin et al., Green Chem., 11 (2009), 1514.
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
Scientific challenges
High pressure reactor installed in an explosion-proof room – similar to OXITENO set-up
Integration and automation of reactor operation software and safety interlocks
Fixed bed reactor set-up
Gas chromatograph
Infrastructure at LSQ-LNLS
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
Catalysts
5% Ru/C
Samples: 5% Ru/C (Acros) 5% Ru/C – LNLS (dry impregnation RuCl3)
1wt.% glycerol, 110 mg of catalyst, 4MPa of H2
Ni2Al3
NiAl3
Al
Ni-Al alloy
Raney Ni catalyst
C.B. Rodella, G. Kellermann, M.S.P. Francisco, M.H. Jordão, D. Zanchet, Ind. Eng. Chem. Res. 2008, 47, 8612.
Samples: Raney Ni 3111A - Grace Co. (1% Mo) Raney Ni 2800 - Grace Co. Raney Ni - LNLS
Raney Ni
10wt.% glycerol, 1,67g of catalyst
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).
Ru/C
C-A C-B C-MERCK
Conversion (%) 26,0 23,7 30,7
Selectivity
(%)
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
*All samples presented traces of acetol .
Carbon support Dependence on the carbon support supplier
P.Trecco (Undergraduate project)
Improves surface area
Tungsten Carbides -Synthesis
Temperature Programmed Carburization (TCP)
WO3 WOx (0x3) W W2C WC
7000C 8500C
9000C 100 – 200 ml.min-1 pure H2 or 10%CH4/H2
+
W
bcc
C
amorphous
W2C
hcp
WC
hex
Temperature or
Promoters like Ni, Fe and Co decrease carburization temperature and improve catalytic activity
Structural characterization XRD - in situ
X Ray beamline
Furnace
θ
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).
WxC
Preliminary results showed low activity in the hydrogenolysis of propane
Ru-NPs NiPt-NPs
Collaboration with Dr. C.S. Claro and F. Requejo - Univ. La Plata, Argentina
Colloidal nanoparticles
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
Funding: FAPESP, Oxiteno, LNLS
Dr. Roberto Rinaldi (Max-Planck) Prof. Victor Teixeira (UFRJ)
Prof. Jose Maria C. Bueno Debora M. Meira Renata U. Ribeiro
Dr. Cecilia Claro (ULP) Dr. Felix Requejo (ULP)
Dr. Jose L. Zotin (CENPES) Sandra Chiaro (CENPES)
