Experimental solubility of fexofenadine hydrochloride (antihistamine) drug in SC-CO2: Evaluation of cubic equations of state

Abstract

Fexofenadine hydrochloride is an antihistamine drug which is used in the treatment of allergy symptoms, like urticaria and hay fever. In this research, the solubility of fexofenadine hydrochloride was measured in supercritical carbon dioxide (SC-CO2) at different pressures (120 to 270 bar) and temperatures (308.2 to 338.2 K), for the first time. The solubility data were in the range of 0.073 < y×104 < 0.854. The experimental data on the solubility of fexofenadine hydrochloride were correlated by two approaches: (1) three cubic equations of state (CEoSs) with two mixing rules, and (2) nine density-based correlations with 3-6 adjustable parameters. Among CEoS, Peng-Robinson EoS with Kwak-Mansoori mixing rule, showed more accuracy, especially at higher pressures with an average absolute relative deviation percent (AARD%) of 5.48. Moreover, Garlapati and Madras (model I) with AARD% of 5.65 showed more accurate correlation compared to density-based models. Finally, total, vaporization, and solvation enthalpies of the fexofenadine hydrochloride-CO2 system were calculated to be 39.5759, 52.4635, and -12.8876 kJ.mol−1, respectively.