Afrida, Neli2023-05-042023-05-042023-01PerpustakaanElfitrahttps://repository.unri.ac.id/handle/123456789/10958In this study, biodiesel was synthesized using crude palm oil (CPO) with a CaOSiO2 catalyst. CaO from blood clam shells and SiO2 from palm shell fly ash. CaOSiO2 catalyst synthesized using the wet impregnation method with variations of SiO2 to CaO 1%, 3% and 5%. Surface area of CaO-SiO2 1% catalyst is is 9,0078 m2g-1 with pore volume is 0,0268 cc g-1, CaO-SiO2 3% catalyst is 9,2241 m2g-1 with pore volume is 9,2241 m2 g-1 and CaO-SiO25% catalyst is 9,2591m2g-1 with pore volume is 0,0298 cc g-1. The functional group obtained is OH indicating Ca(OH)2, Si-O asymmetric stretching vibration Si-O-Si and Ca-O. Purpose of the study is to find best SiO2 variety. Based on research results, the highest biodiesel yield was obtained using a catalyst CaO 3% SiO2 by weight of catalyst 2 g, Mole ratio of oil : methanol 1:9, reaction time 90 minutes, reaction 60°C stirring speed 500 rpm produce biodiesel yield of 73,75%..enbiodieselCaO-SiO2ImpregnationArticle