Solubility Determination and Thermodynamic Modeling of Amitriptyline Hydrochloride in 13 Pure Solvents at Temperatures of 283.15–323.15 K

In this work, the solubility of amitriptyline hydrochloride (AMT) in 13 monosolvents was experimentally measured in the temperatures ranging from 283.15 to 323.15 K under atmospheric pressure with the aid of laser dynamic solubility monitor devices. The solubility as a function of temperature in different monosolvents was regressed using two activity coefficient models (Wilson and nonrandom two liquid (NRTL)) and three semiempirical equations (modified Apelblat, three-parameter Van’t Hoff, and λh), Based on the solubility data and the regression parameters of the Wilson model, the mixing thermodynamic properties (mixing Gibbs energy, mixing enthalpy, mixing entropy) as well as the activity coefficient and the reduced excess enthalpy at infinitesimal concentration were evaluated.