Epoxidation of Soybean Oil and its Blend with Waste Cooking Oil Using H2SO4 as Homogeneous Catalyst

Abstract

Epoxidation of soybean oil is carried out at different conditions such as the feed ratio of C=C/CH3COOH/H2O2 (1:1:1, 1:1:2, 1:2:1, 1:2:2, 1:2:4), reaction temperature (50 °C, 65 °C) and reaction time (3–7 h). Physicochemical properties of the reagent and product such as viscosity at 40 °C and 100 °C, viscosity index, iodine index as well as FT-IR spectral analysis are studied to find out suitable epoxidation reaction conditions. The experiment results showed that conversion of C=C in soybean oil through epoxidation could reach high value (96.0 %) at 65 °C for 5 h of reaction with the C=C/CH3COOH/H2O2 molar ratio of 1:2:4 and viscosity index of epoxidised product was 156. IR results of the epoxidised oil obtained also exhibits that the peaks characteristic for the C=C bond disappear and the peaks characterising for epoxy rings are observed in the product, supporting evidence for epoxidation. Epoxidation of soybean oil blended with waste cooking oil (90:10) is performed at the above suitable condition. The obtained results exhibited that C=C conversion of blended oil could still reach above 98 % and viscosity index of epoxidised oil is 151. The FT-IR spectral analysis of the epoxidised oil also clearly shows the appearance of peaks characterizing the epoxy ring.