Catalytic epoxidation of a mixture of oleic acid and waste cooking oil using a homogeneous catalyst

Abstract This study investigates the in situ epoxidation of a hybrid feedstock comprising waste cooking oil and oleic acid to enhance oxirane conversion for sustainable epoxide groups production. A key challenge with waste cooking oil is its low epoxidation efficiency when used alone. By blending it with oleic acid at a 1:1 weight ratio, a maximum relative conversion to oxirane (RCO) of 63.4% was achieved compared to 29.5% when using waste cooking oil alone accompanied by homogenous catalyst usage. The optimum reaction temperature was found at 70°C. Side reactions were minimal within 30 min of reaction time, but ring opening became significant at a higher temperature (80°C) and longer times. FTIR analysis confirmed successful epoxidation, where the disappearance of CC stretching (~1650 cm −1 ) and the appearance of epoxy ring vibrations (~823 cm −1 ) were observed. Kinetic modeling of the system demonstrated high reaction rates with minimal side reactions, validating the approach's accuracy and robustness. This work presents a novel hybrid strategy to valorize waste cooking oil, offering a more efficient and sustainable route for bio‐based epoxide production.