A GENERALIZED CORRELATION FOR THE INTERACTION COEFFICIENTS OF CO2 HYDROCARBON BINARY-MIXTURES

A generalized correlation for the interaction coefficient (k(ij)) of CO2/n-alkane binary systems with a translated modified Peng-Robinson equation of state (t-mPR EoS) is presented. The correlation involves the CO2 reduced temperature and alkane acentric factor as independent variables and was developed using an extended data base up to n-C-44. Through the use of an ''effective'' acentric factor the correlation is extended to other CO2-hydrocarbon systems. The correlation is limited and does not apply to very asymmetric systems, where the hydrocarbon contains more than one ring. Typical errors in bubble point pressure predictions are below 5-6%. The proposed correlation can also be used with the PR EoS.