MCM-41 Derived from Freshwater Sponge Silica as Support for HPW Applied in the Esterification of Oleic Acid

The MCM-41 was synthesized from freshwater sponge (Metania kiliani) by the hydrothermal process. Aqueous impregnation of commercial 12-tungstophosphoric acid (H3PW12O40; HPW) in 5, 10, 15, 20 and 30 %, respectively, in MCM-41 led to the formation of new catalysts preserving hexagonal mesoporous characteristics and dispersed homogeneously on the surface and in the interior of the MCM41 structure. The characterization of the catalysts was done by the analytical techniques: XRD, FTIR and SEM. For the study purposes, the catalysts were run under the conditions of oleic acid/methanol of molar ratio (1:7), temperature (65 degrees C) and time (5 h) and 5 % (m/m) catalyst. Quantification of biodiesel converted in the esterification process of oleic acid was determined by titration with NaOH. Among the various catalysts, the best performance was HPW30 (MCM-41 + HPW 30%) in 75.1% methyl oleate.