Characterization and aging impact study on antioxidants with CaO catalyzed methyl ester from waste cooking oil as sustainable insulation as biorefinery approach

With a focus on the development of sustainable energy solutions, this research focuses on biomass refinery conversion, this research focuses on the waste cooking oil (WCO) modification as fatty acid methyl ester using the heterogeneous catalyst of calcium oxide (CaO). Preceding liquid insulation production, WCO undergoes vacuum filtration and temperature-induced water evaporation to remove impurities. For enhancing feedstock suitability for transesterification, free fatty acids (FFAs) are eliminated through coal ash adsorption with WCO. The process employs CaO as a heterogeneous catalyst with optimized parameters. The study evaluates electrical and physicochemical parameters of the processed oil under normal and aging conditions based on ASTM and IEC standards, examining both new and aged conditions. The findings highlight improved WCO’s fatty acid methyl ester (FAME) characteristics after transesterification. Further inclusion of TBHQ and PG antioxidants (0.5wt% concentration) enhanced the oxidation stability index (OSI) by 3.5 times and 3 times, respectively. They also improve the breakdown voltage of the sample by 24.3% and 13.5% from its initial values. While aging of FAME with antioxidants minimally affects the breakdown voltage and OSI of the sample. This study draws attention to the potential for liquid insulation developed from waste cooking oil to mitigate environmental impact and promote eco-friendly practices in the energy and electrical sectors.