Boyle temperature from SAFT, PC-SAFT and SAFT-VR equations of state

Abstract

Second virial coefficient, Boyle temperature and Zeno (unit compressibility) line of some polar, non-polar and associating substances are calculated from SAFT, PC-SAFT and SAFT-VR equations of state (EOS). The results are compared with the corresponding values obtained from published correlations and available data.Our investigation shows that among the three EOSs considered the results obtained from the SAFT EOS are more accurate in predicting the Boyle temperature and the Zeno line. For second virial coefficient prediction, PC-SAFT is superior to SAFT for many substances and, for some alkanols and water; the results of SAFT-VR are more accurate.A modification on Tsonopoulos correlation for the second virial coefficient is presented for branched-alcohols and amines which has reduced the average absolute percent relative deviation (AAD%) from 13.22 to 3.52 and from 14.55 to 6.00 for four branched-alcohol and two amines, respectively. The proposed modification uses the Boyle temperature obtained from the SAFT EOS as a property of substance.