HIGH-PERFORMANCE CaO/SiO2 COMPOSITE PREPARED FROM LIMESTONE AND PUMICE SILICA AS CATALYST FOR RUBBER SEED OIL TRANSESTERIFICATION

Abstract

In this work, five CaO/SiO2 composites with different mass ratios were synthesized from limestone and pumice silica and subsequently applied as catalysts for the transesterification of rubber seed oil. A series of experiments were conducted to evaluate the effect of catalyst compositions, calcination temperatures, and other reaction variables including catalyst loads, methanol to oil (M/O) ratios, and reaction times on the reaction yields. The catalyst exhibited the highest activity and was characterized using X-ray diffraction (XRD) and Scanning Electron Microscope (SEM). The results displayed promising activities of the CaO/SiO2 composites synthesized, with the highest transesterification yield of 100% achieved using a CaO/SiO2 catalyst with a ratio of 1:5 calcined at a temperature of 800 C. This complete conversion of the oil into biodiesel was achieved with the use of a catalyst load of 2.5% of the mass of the oil, an M/O ratio of 6:1, and a reaction range of 6 hours. The overall results demonstrated that CaO/SiO2 synthesized has the promising potential as a catalyst to support biodiesel production from various feedstock.