Base-Catalysed Epoxidation of Cooking Oil via In Situ Peracid Formation

The conversion of vegetable oils into high-value epoxidised derivatives has gained increasing relevance as industries seek renewable and safer alternatives to petroleum-based materials; however, conventional acid-catalysed systems remain limited by corrosiveness, difficult separation, and environmental concerns.Addressing these challenges, this study evaluates the epoxidation of palm cooking oil via an in situ peracid mechanism using sodium hydroxide (NaOH) as a base catalyst and hydrochloric acid (HCl) as an acid catalyst, with the aim of elucidating their comparative performance and reaction behaviour.The reactions were conducted using formic acid and hydrogen peroxide under controlled conditions, with catalyst loadings varied to assess their influence on oxirane formation.Samples were collected at 10-minute intervals for titrimetric quantification of oxirane oxygen.Kinetic modelling was applied to determine rate constants and to interpret the mechanistic differences between the catalytic systems.NaOH achieved the highest relative conversion to oxirane (RCO), reaching 59.96 % at 40 min, compared with 50.12 % for HCl, while FTIR analysis confirmed the successful formation of epoxide functionalities in both pathways.These findings highlight the potential of base-catalysed epoxidation as a greener and operationally safer route for producing epoxidised vegetable oils suitable for downstream polymer applications.