Synthesis and Characterization of CaO Limestone from Lintau Buo Supported by TiO<sub>2</sub> as a Heterogeneous Catalyst in the Production of Biodiesel

Biodiesel constitutes an alternative to diesel fuel, developing a base catalyst in cost efficiency and reducing the impact on environment due toxic waste excessive chemicals. This study employed mixture of oxide catalyst, CaO/TiO2, which was ably synthesized as heterogeneous convert frying oil (WFO) into biodiesel. Heterogeneous catalysts have been characterized by XRD, FT-IR, TEM, SEM-EDX, BET identify their crystal type, morphology, composition, surface area. Catalytic activity affected amount, oil/methanol ratio, reaction temperature, duration. A 94% biodiesel yield achieved optimizing following parameters: 5wt.%, 6:1 methanol: oil, 65 °C, for 4 h. The addition TiO2 CaO improves stability transforms reactants products. structure characteristics maintained supported well. Its repeated fuel production demonstrated from WFO throughout transesterification reaction.