KARAKTERISASI BIODIESEL DARI MINYAK KEMIRI SUNAN DENGAN KATALIS HETEROGEN SILIKA TERIMPREGNASI KALSIUM OKSIDA (CaO/SiO2)

Abstract

Commercial biodiesel of oil palm is controversial as the palm oil is classified as food oil and palm plantation utilizes fertile land. One potential type of vegetable oil as biodiesel raw material is kemiri sunan (Reutealis trisperma (Blanco) Airy Shaw) oil. This research aimed to prepare a heterogeneous solid catalyst in the form of an impregnated SiO 2 by CaO catalyst (CaO/SiO 2 ), to study the effect of the esterification stage on free fatty acid (FFA) content of oil, and to test the activity of the CaO/SiO 2 catalyst during the trans-esterification stage for biodiesel formation. CaO/ SiO 2 catalysts were prepared by sol-gel method made from natural materials (egg shells and rice husk). The FFA content of kemiri sunan oil was determined through various esterification stages namely 1; 1.5; and 2 hours in the presence of H 2 SO 4 catalyst. While the trans-esterification stage was carried out under reaction temperature of 60 °C, oil to methanol ratio of 1:9, reaction time of 2 hours and CaO/SiO 2 catalyst content of 3%. The results showed that the esterification stage for 1; 1.5; and 2 hours reduced the FFA content from 12.5% (without esterification) to 0.65%; 0.58%; and 0.54% respectivaly. Biodiesel made from kemiri sunan oil which was synthesized with the addition of CaO/SiO 2 catalyst at optimal conditions of trans-esterification stage fulfilled SNI 7182-2015: Biodiesel based on density, viscocity, moisture content, iodine number, and cetane number.