The interplay of phase equilibria and chemical kinetics in a liquid/liquid multiphase biodiesel reactor

A countercurrent liquid/liquid phase biodiesel reactor achieved 99% triglyceride to methyl ester conversion at the same time as separating 90% of the produced glycerin. However, a low inverse sensitivity of the conversion to the glycerin separation efficiency led to biodiesel that did not meet ASTM quality standards in previous work. A distributed methanol injection strategy is demonstrated herein to improve reactor performance, yielding ASTM quality biodiesel and 90% separation efficiencies. Preliminary data on feed rate changes yields counterintuitive results where conversion increases as feed rate increases. A model that assumes equilibrium between the reacting oil phase and the settling glycerol phase simulates the experimental results and provides insight into the reactor behavior.