Estimation of Physical Constants of Biodiesel-Related Fatty Acid Alkyl Esters: Normal Boiling Point, Critical Temperature, Critical Pressure, and Acentric Factor

A comprehensive study regarding the estimation of normal boiling points, critical temperatures, critical pressures, and acentric factors of biodiesel-related esters is presented. Such properties are crucial for simulations of chemical processes involving biodiesel. Although reliable experimental data are available for some esters, their determination for all the existing biodiesel components is an expensive and cumbersome task. In view of that, this work aimed to investigate the performance of group contribution and corresponding state models in the calculation of these properties. The estimation models were tested in terms of accuracy and of the plausibility of combining experimental and calculated values without violating the expected physical behavior for corresponding pairs of esters and for esters belonging to the same homologous series. The main outcome of this work is a recommendation of the most feasible models for engineering applications.