Solubilities of 5,10,15,20-tetrakis(4-chlorophenyl) porphyrin and 5,10,15,20-tetrakis(4-chlorophenyl) porphyrin manganese(III) chloride in binary ethanol + water solvent mixtures

Abstract The solubilities of 5,10,15,20-tetrakis(4-chlorophenyl) porphyrin (abbreviated in p -ClTPP) in ethanol + water solvent mixtures at (293.2–333.2) K and 5,10,15,20-tetrakis(4-chlorophenyl) porphyrin manganese(III) chloride (abbreviated in p -ClTPPMnCl) in ethanol + water solvent mixtures at (303.2–333.2) K were measured. The concentration of ethanol in term of mole fraction on the solubility was studied. It was found that the solubility of p -ClTPP in ethanol + water solvent mixtures increases with the increasing of temperature at constant solvent composition, and decreases with the decreasing mole fraction of ethanol at constant temperature. However, for p -ClTPPMnCl, the solubility increases with the increasing of temperature at the mole fraction of ethanol from (0.6102–0.8597), and decreases with the increasing of temperature at the mole fraction of ethanol from (0.9038–1.0000). The experimental data were correlated with the modified Apelblat equation, and the solubilities correlated by the model were in good agreement with experimental data. Thermodynamic parameters including dissolution enthalpy, dissolution entropy and dissolution Gibbs free energy were calculated with van’t Hoff equation.