Abstract
Recently, the application of heterogeneous catalyst has attracted considerable interest in biodiesel production compared to homogenous catalyst because of its reusability in successive reactions runs and easier to separate from the reaction mixture. Thus, attempts have been directed to develop supported catalyst to improve the efficiency and recovering ability of the prepared catalyst. In this study, a renewable low cost heterogeneous hybrid catalyst through utilization of waste material; rice husk and eggshell was synthesized via wet impregnation method. The performance of CaO impregnated with silica was tested for its catalytic activity via transesterification of waste cooking oil. The effect of silica content, catalyst loading, methanol to oil molar ratio, reaction time and reaction temperature on biodiesel yield were investigated. The result show that the calcium oxide (CaO) supported with silica is more effective for the production of biodiesel compared to CaO individually. Furthermore, it was determined that the transesterification conditions of 3 wt % catalyst loading. 15:1 methanol to oil molar ratio, 90 min reaction time and 60 ºC reaction temperatures resulted in biodiesel yield of 90 %.
