Synthesis and Process Variables Optimization of Al2O3-CaO Catalyst (from Eggshell) for Biodiesel Production

Abstract

The synthesis of alumina-calcium oxide catalyst, optimization of process variables and application of the synthesized catalyst is presented. The effect of the variables during the synthesis of the catalyst was investigated through transesterification. The synthesised catalysts were characterised. Using a 24 factorial design, the impregnation ratio, impregnation time, calcination temperature and calcination time as parameters used in catalyst synthesis were investigated on the yield of biodiesel from waste cooking oil. The optimization study showed that; impregnation ratio of 1.17:1 at 1.32 h of impregnation and calcination temperature of 740.31 °C for 2.62 h gave the best results of 75.4% with 95% confidence level when used biodiesel production. The conditions for transesterification of the waste cooking oil were methanol to oil molar ratio of 12:1, 6 wt% catalyst, 60 °C reaction time, and mixing speed of 250 rpm for 90 min. The optimized result agreed with the experimental yield of 76.02% biodiesel using the same conditions