Optimization process of biodiesel synthesis using heterogeneous base catalysts

Abstract

The most properly used study for biodiesel preparation is via homogeneous transesterification of vegetable oil using alkaline catalysts. Biodiesel yield and oil conversions are affected by a lot of parameters including the catalyst type and amount. The heterogeneous catalysis for biodiesel production has been extensively investigated for the latest few years. This study has evaluated the heterogeneous base catalyst effects on biodiesel yield and total glycerin in transesterification butanol and sunflower oil at different catalyst amount, reaction time and butanol to oil molar ratios. There exist three different heterogeneous base catalysts, magnesium oxide, calcium oxide, sodium aluminate. It has been observed that the sodium aluminate catalyst leads to better butyl ester yields that comply the specification of standard methods (ASTM D 6751 & EN 14214). The highest approximately 95% butyl ester yield acquires 12:1butanol-to-oil molar ratios, 1.5 Wt.% sodium aluminate catalyst at 150oC reaction temperature and 1200 rpm stirring speed under optimum conditions.