Kinetics of the Transesterification Reaction Catalyzed by Solid Base in a Fixed-Bed Reactor

Kinetics of the transesterification reaction catalyzed by solid base in a fixed-bed reactor was studied in this paper The transesterification reaction between palm oil and methanol was catalyzed by KF/Ca-Mg-Al hydrotalcite solid base, which made it a complicated liquid-liquid-solid heterogeneous reaction Isopropyl ether was used to obtain a homogeneous reactant system, and then liquid-liquid mass transfer limitations were eliminated Experimental results showed that, when the feed rate was faster than 0 3 mL/min, liquid-solid external diffusion mass-transfer limitations were negligible and, when the diameter of the catalyst particle was not larger than 0 18 mm liquid-solid internal diffusion mass transfer limitations could be neglected as well Then, intrinsic reaction rates of this transesterification under different space velocities, temperatures, and concentrations were measured in a fixed bed integral reactor An intrinsic kinetic model was developed on the basis of the Eley-Rideal mechanism according to the experimental data, which indicated a new mechanism of the transesterification reaction catalyzed by solid base The transesterification reaction occurred between methanol adsorbed on solid base active sites and glyceride from the liquid phase The surface reaction of triglyceride with adsorbed methanol was assumed to be rate determining The model calculation agreed well with experimental data Regression of experimental data indicated that the transesterification reaction was an endothermic reaction and the activation energy was 111 6 kJ/mol