Catalytic activity of Cu-CeO2-ZrO2 for biodiesel production

W. Wongvitvichot, S. Jampa, A. Luengnaruemitchai, T. Chaisuwan, S. Wongkasemjit
Chulalongkorn University,

Keywords: Cu-CeO2-ZrO2, biodiesel production


Ceria-Zirconia (CeO2-ZrO2, CZ) was synthesized using two different methods, coprecipitation (copre) and nanocasting (nanocast), for using as support material for copper (Cu) catalyst. Cu-CeO2-ZrO2 (CuCZ) was applied for esterification reaction in biodiesel production. Structure and specific surface area of the synthesized CeO2-ZrO2 were characterized by X-ray diffraction (XRD) and N2 adsorption-desorption. Both copre and nanocast CZ exhibited the fluorite-type cubic crystal structure of the CeO2 phase with different specific surface areas of 95.3 and 230.2 m2/g, respectively. Copper with 9%wt loaded onto copre and nanocast CZ showed specific surface areas of 77.3 and 176.2 m2/g with average pore size of 5 and 6 nm, respectively. XRD result of copre CuCZ exhibited the diffraction peak of CuO, indicating the agglomeration of Cu species on copre CZ support while nanocast CuCZ presented high dispersion of Cu species, as confirmed by no diffraction peaks from CuO crystallites in the XRD result. Both copre and nanocast CuCZ catalysts were treated with sulfuric acid by wet impregnation technique. The catalytic activity for esterification reaction of the treated copre and nanocast CuCZ catalysts was evaluated using oleic acid and methanol as reactants and solvent via microwave technique. Effects of variables, such as sulfuric acid concentration, molar ratio of methanol to oleic acid, reaction temperature, reaction time, and amount of catalyst, on the esterification reaction were studied to reach high biodiesel yield. The preliminarily obtained biodiesel yield was higher than 95%. More details will be discussed.