Kinetics of rapeseed oil transesterification over a heterogeneous barium-aluminum oxide catalyst with the methanol pressure taken into account

Abstract

Use of heterogeneous catalysts in the synthesis of biodiesel from vegetable lipids via transesterification with alcohols has certain advantages over use of homogeneous catalysts. Commercialization of this process needs investigation of its kinetics. Here, we report, for the first time, the kinetics of transesterification of rapeseed oil with gaseous methanol over a heterogeneous catalyst with methanol partial pressure taken into account. Experiments have been carried out in a flow reactor with a fixed bed of a barium-aluminum oxide catalyst at 200°C and a methanol pressure of 0.1–2.5 MPa. Experimental data have been processed in terms of a simplified kinetic model involving one irreversible second-order reaction (first-order reaction with respect to both oil and methanol). Service life tests have been carried out for the catalyst calcined at 700°C.