Synthesis of carbonated vegetable oils: Investigation of microwave effect in a pressurized continuous-flow recycle batch reactor

•A microwave-assisted continues-flow recycle batch reactor for gas–liquid reactions.•Investigation of microwave effect on the carbonation of cottonseed oil methyl ester.•Kinetic modeling for comparison between conventional and microwave heating.•A minor decrease in reaction activation energy under microwave. With the depletion of fossil resources, it is essential for the chemical industry to find alternative raw materials for polymers. Polyurethanes can be synthesized from vegetable oils and CO2 via an environmentally friendly, non-isocyanate pathway. Carbonation of epoxidized vegetable oil is a key step allowing the feasibility of this method. Because it requires a high temperature, high pressure and long reaction time to achieve complete conversion, microwave technology (MW) is an interesting approach for the intensification of the carbonation process. However, MW-irradiated batch reactor has multiple issues regarding scale-up. A microwave irradiated continuous-flow recycle batch reactor which can operate at high temperature (130°C) and moderate pressure (8bar) was used in the present work. The effect of microwave irradiation on the kinetics of carbonation reaction was studied. A kinetic model was developed to compare quantitatively the performance under microwave and conventional heating (CH). It was found that the activation energy of the carbonation reaction was slightly lower with the use of MW irradiation, where the values for CH and MW are respectively 0.385E+04J/mol and 0.338E+04J/mol.