Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia

PL-5PRODUCTION OF BIODIESEL BY A TWO-STEP NIOBIUM OXIDECATALYZED HYDROLYSIS AND ESTERIFICATION ∗Donato Aranda 1 , Layla Rocha 1 , André Ramos 2 , and Nelson Antoniosi-Filho 31 GREENTEC/EQ/UFRJ, Brazil, donato@eq.ufrj.br2 DEQ/UFS, Brazil3 LAMES/UFG, BrazilBiodiesel is a biofuel with several advantages compared to petroleum diesel [1].The most used route to produce it is the homogeneous basic catalytictransesterification of triglycerides [2], but this process has some inconvenients, asthe rigorous control of raw materials and several post-reaction separation steps [3].This work deals with an alternative process: the use of a heterogeneous acid catalyst(Nb 2 O 5 ) to promote both hydrolysis of triglycerides (soybean and castor oils) andesterification of the produced fatty acids. Reactions were performed in a stainlesssteel batch reactor with controlled stirring and heating. A experimental design wasperformed to optmize temperature–T (250-300°C for hydrolysis, 150-200°C foresterification), water/oil and methanol/fatty acid molar ratios-R (5-20 for hydrolysis,1.2-3 for esterification) and catalyst concentration-C (0-20% w/w for both reactions).Conversion was measured by acid-base titration and gas chromatography. Kineticand molecular modeling was also performed. Tables 1 and 2 show some conversionsobtained in both reactions at 60 min, being clear the effect of temperature andcatalyst concentration. Cracking was detected as side reaction at highertemperatures. The kinetic modeling has shown different kinetics without and withcatalyst, being the hydrolysis inhibited by water and zero order for the other reactantswithout catalyst, while second order in relation to the reactant which was not inexcess was observed in catalyzed reactions.The higher reactivity of liloleic acidcompared to ricinoleic acid was justified by energy differences of homo and lumoorbitals.Table 1 Table 2Hydrolysis of soybean oilEsterification of fatty acids from soybean oilConditions (t=1 h) Conversion (%) Conditions (t=1h) Conversion (%)T=250°C, R=20, C=0 46.89 T=150°C, R=1.2, C=0 51.63T=250°C, R=20, C=20 66.83 T=150°C, R=1.2, C=20 63.83T=300°C, R=20, C=20 85.08 T=200°C, R=1.2, C=20 82.79[1]. E. Lotero et al. Ind. Eng. Chem. Res. 2005, 44, 5353-5363.[2]. A. Demirbas. Energy Convers. Manage 2008, 49, 125-130.[3]. F. Ma; M.A. Hanna. Bioresour. Technol. 1999, 70, 1-15.∗ Prof. Aranda will present the plenary lecture «TRANSESTERIFICATION AND HYDROESTERIFICATION:THEORETICAL AND EXPERIMENTAL ANALYSIS OF BIODIESEL PRODUCTION USING HETEROGENEOUSCATALYSIS» based on the materials of his two presentations.10