III International Conference

PP-III-12NOVEL CHITOSAN-BASED CATALYSTS FOR BIODIESEL PRODUCTION FROMRENEWABLE NATURAL FEEDSTOCKKramareva N.V., Kucherov A.V., Tkachenko O.P., Kustov L.M.N.D. Zelinsky Institute of Organic Chemistry, RAS, Moscow, RussiaE-mail: nkramareva@mail.ruA number of chitosan complexes with different metals (Zn, Co, Ca, Ni, Mn, Sn, Pb) weresynthesized and tested as catalysts in a reaction of transesterification of tributyrine simulatingthe process of biodiesel production from renewable natural feedstock (triglicerides, vegetableoils). It is found that chitosan complexes are stable and effective catalysts for transformationof tributirine into the corresponding ester. Sn, Pb, Ca-containing complexes were successfullyimplicated for transesterification of vegetable oils (sunflower-seed oil, olive oil).Immobilization of transition metal complexes on the surface of polymer supports enablesdesigning new catalysts that combine the advantages of homogeneous catalytic systems andheterogeneous ones. Chitosan, a biopolymer (poly(1-4)-N-acetyl-β-D-glucosamine) extractedby deacetylation of chitin, the component of crab shells, insects, and plant cell walls, is one ofthe most abundant natural polysaccharides. Catalysts on the basis of chitosan and itsderivatives could be considered as good candidates for the “Green catalysis”.A number of chitosan-based complexes with different metals (Zn, Co, Ca, Ni, Mn, Sn,Pb) prepared by coprecipitation and adsorption techniques were immobilized on the surface ofmacroporous silica to produce the egg-shell catalysts. As we found earlier this type ofcatalysts possess the more developed surface and higher mechanical stability as comparedwith bulky chitosan complexes. The structure and stability of complexes prepared wereinvestigated by different methods (EXAFS, XPS, IR, and SEM). Catalytic activity ofheterogenized chitosan-supported ions was compared with activity of homogeneousmacroligand-free samples. The influence of counter-ion (Cl - , Br - , CH 3 COO - , NO - 3 ) oncatalytic activity of the chitosan complex was also investigated. Catalytic testing revealed agood performance of all the catalysts for the reaction of transesterification, with Sn, Pb, andCa-chitosan complexes demonstrating the best catalytic activity. Tributyrin conversionreached 95% for Pb- and Ca-containing catalysts, and 85% for Sn-sample, with selectivity98% (60-70 o C; reaction time 3-6 hrs). Sn, Pb, Ca-containing complexes were successfullyimplicated for transesterification of vegetable oils (sunflower-seed oil, olive oil).491