The kinetics of the epoxidation reaction of sunflower oil utilizing peroxyformic acid generated in situ

Sunflower oil, rich in unsaturated fatty acids, is a promising renewable resource for bioplasticizers and biopolyols. While extensive research has been conducted on vegetable oil epoxidation, the kinetics of sunflower oil epoxidation using in situ-generated peroxyformic acid remains insufficiently explored. Most studies focus on peroxyacetic acid, leaving a gap in understanding the reaction kinetics and key parameters for peroxyformic acid epoxidation. This study investigates the kinetics of sunflower oil epoxidation using in situ-generated peroxyformic acid with a sulfuric acid catalyst. The effects of reaction temperature, time, and the molar ratio of double bonds to hydrogen peroxide were examined. A kinetic model was developed, and key parameters were determined, including reaction rate constants and activation energy. Results showed that temperature, reaction time, and reactant ratios significantly influenced iodine and oxirane conversions. While higher temperatures and prolonged reaction times initially increased oxirane conversion, excessive heat led to side reactions, reducing efficiency. The optimal conditions for epoxidation were found to be 60°C, a reaction time of 3 hours, and a 1:2.0 molar ratio of double bonds to hydrogen peroxide, yielding the highest oxirane content. The reaction rate constants ranged from 7.7 to 14.6 × 10 -6 liter/mol·s, with an activation energy of 19.4 kJ/mol. These findings provide critical insights into optimizing sunflower oil epoxidation, facilitating its potential use in sustainable biopolyol and bioplasticizer production.