Synthesis of Biodiesel Catalyzed by Phosphotungstic Acid Supported on Silica

Abstract Using tetraethyl orthosilicate as silicon source, silica supported phosphotungstic acid catalyst was prepared by sol-gel method, and then biodiesel was synthesized from Vegetable oil and methanol with self-made solid acid as catalyst. Through the temperature, time, dosage, use times and other factors. The optimal conditions for conversion were found to be 40% phosphotungstic acid loading. 6: 1 ratio of alcohol to oil, the catalyst dosage is 10% of the rapeseed oil mass, and the reaction temperature was set at 68°C and the reaction time was 2.5h. Under these conditions, the conversion rate of biodiesel can reach 96.0%.