Prediction of polycyclic aromatic hydrocarbon solubilities in benzene

Abstract

AbstractSolubilities of polycyclic aromatic hydrocarbon (PAH) solutes; naphthalene, fluorene, acenaphthene, fluoranthene, anthracene, phenanthrene, pyrene, chrysene and triphenylene in benzene are predicted using UNIFAC, modified UNIFAC (Dortmund), and combination of Flory‐Huggins and Scatchard‐Hildebrand (FH‐SH) methods. Applicability of the R‐UNIFAC method to the binary PAHs in benzene systems is studied. Exponent R of the R‐UNIFAC method is used in the modified UNIFAC (Dortmund) model to get a new expression for combinatorial activity coefficient. It is shown that the group contribution models using exponent R in combinatorial part of the equation perform much better than the original ones but none of the models considered satisfactorily predicts solid‐liquid equilibria (SLE) of all PAHs studied (FH‐SH model gives a prediction error of 98.08% for chrysene + benzene system). It is also shown that accounting the heat capacity change on melting terms makes considerable difference with ideal solubility in the case of higher melting PAHs in benzene. Copyright © 2007 Curtin University of Technology and John Wiley & Sons, Ltd.