Base-Catalyzed Transesterification vs. Supercritical Methanol Transesterification in the Optimization, Rigorous Model Simulation, and Heat Integration for Biodiesel Production

Nessren M. Farrag, Mamdouh A. Gadalla, Mai K. Fouad


Biodiesel production is worthy of continued study and optimization of production procedures due to its environmentally beneficial attributes and renewable nature. This study aims to investigate the optimum conditions and optimum production unit for the production of biodiesel from waste vegetable oil. Two production processes were considered: one using base-catalyzed transesterification, and the second is non-catalytic transesterification (using methanol at very high temperature and pressure). Through optimizing the process variables that affect the yield and purity of biodiesel, optimal transesterification conditions that produce maximum biodiesel yield were reached. Furthermore, the optimum production process that consumes less heating and cooling energy and has less environmental impact was identified. The surface plot, contour plot, and the Pareto chart were used to represent and relate the influence of the process variables on biodiesel yield. The parameters were correlated with the biodiesel yield using linear regression analysis. HYSYS model was developed for both techniques using the optimum conditions to figure out the optimum reactor dimensions required for the two processes at these conditions. A detailed comparison between the two processes was discussed, including the CO2 emissions for the two processes, the energy required for both, and energy integration to minimize the energy supplied as possible. Finally, economic aspects and cost analysis were also discussed.


Keywords: base-catalyzed transesterification, supercritical methanol transesterification, Pareto chart, contour plot, surface plot, heat integration.


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