Subject Area

Chemical Engineering

Article Type

Original Study


The kinetics of heterogeneous catalyzed trans-esterification between castor oil and methanol was studied and modeled. Kinetic data was obtained from a perfectly mixed slurry batch reactor. The modeling was conducted via the modified-hattori mechanism to determine the exact rate controlling step for the reaction. A total of five rate expressions were formed, which were as a result of; methanol adsorption, Triglyceride adsorption, Formation of the complex, Surface reaction and Glycerol desorption. Evaluation of best fitting model and parameter estimation was done using the nealder simplex least square optimization algorithm with the aid MATLAB software. The result from the regression analysis indicated that a kinetic model based on the modified hattori mechanism gave a good fit for the experimental data when assuming the formation of intermediate as the rate determining step. Visual depiction of the conversion and time values for the experimental and the theoretical procedure are also produced to show visual contrast between the two procedures both for experimental and the theoretical. Other models derived from the other mechanisms were rejected based on statistical analysis, mechanistic considerations and physicochemical interpretation of the parameters. Thus, the study gives exact rate controlling step for heterogeneous catalysis to be used for the reactor design and cost-effective production of biodiesel.


Castor Oil, Mechanistic modelling, Heterogeneous system, Parameter Estimation, Rate Controlling step

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Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.