Marlinda, Ririn2025-01-092025-01-092023-12PerpustakaanElfitrahttps://repository.unri.ac.id/handle/123456789/11423Calcium oxide (CaO) is a catalyst that is widely used for biodiesel synthesis reactions because it has relatively high base strength, but the CaO catalyst has the weakness of a low surface area. Therefore, to increase biodiesel yield the CaO catalyst needs to be modified using silica to increase the surface area of the catalyst and its catalytic activity. The aim of this research is to synthesize and characterize the CaO catalyst modified by SiO2 areca palm ash using the impregnation method with the SiO2 ratio of 3% w/w to the weight of CaO. The resulting catalyst was applied for biodiesel production with yield optimization using a Response Surface Methodology (RSM) design. Analysis using BET shows that the surface area of CaO-SiO2 has increased. XRF analysis for the 3% CaO-SiO2 catalyst obtained a SiO2 composition of 0.66 and a CaO composition of 97.496%. Based on the optimum results, the highest biodiesel yield was 94.29%.enbiodieselcatalystand silicaArticle