Degradation of autocatalytic epoxidation of oleic acid derived from palm oil via in situ performic mechanism / Hamzah Hafizuddin Habri

Epoxidized vegetable oils have a demand in the market and are widely known in oleochemical industry to enhance the end-product and as intermediates in chemical reactions. This study interest shown to epoxidation of oleic acid because of high content of unsaturated fatty acids, and the process breaks the double bond then transforms into reactive oxirane ring without presence of catalyst. The autocatalytic epoxidation of oleic acid was carried out by using in situ generated performic acid to produce epoxidized oleic acid. Performic acid was formed by mixing formic acid (as oxygen carrier) and hydrogen peroxide (as oxygen donor). The epoxidation reactions were conducted by varying the type of oxygen carrier, concentration of hydrogen peroxide, stirring speed and formic acid to oleic acid molar ratio. The results showed that optimum condition included formic acid as the excellent oxygen carrier, 50% concentration of hydrogen peroxide, stirring speed at 400 rpm and molar ratio 2.5:1 formic acid to oleic acid. It was found that a maximum relative conversion to oxirane (RCO) achieved was 87 % at optimal condition. There was a good fit between experiment and simulation values of optimum condition with the slightest difference of ~0.20 based on kinetics study attained. The degradation of epoxidized oleic acid after oxirane ring opening invites hydroxylation reaction take place called alcoholysis and hydrolysis. The hydroxyl value from alcoholysis was 346.9 mg KOH/g while the hydroxyl value of hydrolysis was 296.4 mg KOH/g using autocatalyzed reaction. Moreover, the hydroxyl value can vary depending on molar ratio of alcohol and water towards epoxidized oleic acid. In conclusion, high and low hydroxyl value has their own benefits as intermediate product for polymer application such as flexible polyurethane and rigid polyurethane.