A Comparative Study on Predictions of Vapor Liquid Equilibrium of Biodiesel Systems

Abstract

In process simulation, reliable and accurate property estimation methods play an important role in the solution of various simulation problems where convergence is often traced to failures in the reliable predictions of physical and thermodynamic properties. Convergence and reliability of the simulation is heavily dependent on the fluid package selected. Predictions of phase equilibrium using various thermodynamic models provide an idea about which model will be able to represent the entire process in better way. No such systematic studies are done in the literature for biodiesel. Paper presents a review on various simulation studies done for biodiesel production to highlight the fact that the thermodynamic models were used with little knowledge or by intuitions. A comparative study is presented for the proper selection of fluid package by determining vapor liquid equilibrium data for various (fatty acid-alcohol, fatty acid-glycerol, alcohol-glycerol, fatty acid ester- alcohol etc) biodiesel systems. The comparison was done with the help of making a model of experimental VLE data and simulated VLE data (by various thermodynamic models).