Catalysts for glycerol hydrogenolysis: production of glycols from biomass derivatives

Transcription

1 Catalysts for glycerol hydrogenolysis: production of glycols from biomass derivatives Daniela Zanchet Instituto de Química, UNICAMP, Campinas, SP 2007/ PITE project as part of FAPESP-OXITENO and BIOEN initiative Term: 10/ /2011

2 Team 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 Collaborators Dr. Roberto Rinaldi (Max-Planck) Prof. Victor Teixeira (UFRJ)

3 Goal Glycerol major by-product of biodiesel production (low cost, large volume). New opportunites ( glycerochemistry ) Glycerol Hydrogenolysis H 2 H 2

4 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

5 Scientific challenges Glycerol hydrogenolysis is a complex chemical reaction parallel pathways and reactions (reforming, WGS, methanation) -H 2 O H +H 2 H A. Torres et al., Ind. Eng. Chem. Res., 2010; C.J. Mota et al. Quimica Nova, 2009.

6 Coupled reactions Reforming+ hydrogenolysis Roy et al, Cat. Today, 156 (2010), 31; Yin et al., Green Chem., 11 (2009), 1514.

7 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

8 Integration and automation of reactor operation software and safety interlocks Infrastructure at LSQ-LNLS High pressure reactor installed in an explosionproof room similar to OXITENO set-up Gas chromatograph Fixed bed reactor set-up

9 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 H 2 ) 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

10 5% Ru/C Samples: 5% Ru/C (Acros) 5% Ru/C LNLS (dry impregnation RuCl 3 ) 1wt.% glycerol, 110 mg of catalyst, 4MPa of H 2

11 Raney Ni catalyst Ni-Al alloy Raney Ni Al Ni 2 Al 3 NiAl 3 Samples: Raney Ni 3111A - Grace Co. (1% Mo) Raney Ni 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.

12 Raney Ni x Ru/C Both produce large amounts of gas (CO 2, CH 4 ) Raney Ni 1,2-PG Ru/C EG H 2 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).

13 Carbon support Dependence on the carbon support supplier 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 CO 2 1,6 0,4 - CH 4 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. P.Trecco (Undergraduate project)

14 Tungsten Carbides -Synthesis Temperature Programmed Carburization (TCP) Improves surface area WO 3 WO x (0 x 3) W W 2 C WC ml.min -1 pure H 2 or 10%CH 4 /H C C C W C W 2 C WC + Temperature or bcc amorphous hcp hex Promoters like Ni, Fe and Co decrease carburization temperature and improve catalytic activity

15 Structural characterization XRD - in situ Furnace θ X Ray beamline

16 WxC Structural and surface properties - dependent on the gas used in the carburization process and presence of Ni H 2 well crystallized W 2 C, carbon deposition and low conversion 20%CH 4 /H 2 smaller particles, less carbon deposition and higher conversion. Ni carburization at lower temperature (100 K) Glycerol hydrogenolysis favors 1,2-PG (acetol pathway).

17 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

18 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 CH 4 /H 2 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

19 Acknowledgments Dr. Cristiane Rodella (WxC - LNLS) Dr. Silvia Moya (CTBE) Dr. Ricardo Chimentão Ligia Rodrigues Rafael Ferreira LNLS staff Prof. Jose Maria C. Bueno Debora M. Meira Renata U. Ribeiro Dr. Valéria Vicentini Carla Queiroz Oxiteno staff Dr. Roberto Rinaldi (Max-Planck) Prof. Victor Teixeira (UFRJ) Dr. Cecilia Claro (ULP) Dr. Felix Requejo (ULP) Dr. Jose L. Zotin (CENPES) Sandra Chiaro (CENPES) Funding: FAPESP, Oxiteno, LNLS