Numerical Investigation of Biodiesel Production in Capillary Microreactor

Synthesis of biodiesel through transesterification of vegetable oil with methanol has been experimentally studied in different types of microreactors though detailed numerical simulation has not yet been presented. The capillary microreactor has the potential to greatly intensify mass transfer between immiscible fluids that would result in higher chemical reaction rates. A segmented flow pattern of oil and methanol forms within the reactor. It has been shown experimentally that the two phase flow has dramatic benefits on the intensification of mass transfer and heat transfer. Such reactors have been proposed for the synthesis of biodiesel and detailed understanding of flow dynamics and chemical kinetics would be useful for process optimization. This paper presents a mathematical model and numerical solution for the synthesis of biodiesel in a capillary reactor. The model represents the unsteady incompressible viscous non-equilibrium chemically reacting flow. The equations are discretized with the finite element method (FEM) and solved to demonstrate the flow behavior and concentration distribution of each chemical species within two phases; different residence time will be obtained with different volume flow rate as well. Information about efficient computational treatment of the model will also be presented.