Electrolytic effects on solubility and Gibbs free energies of 1,4-dihydroxy-9,10-anthraquinone in aqueous methanol media via UV–Vis spectroscopic and theoretical studies

Abstract

In the study we have estimated the solubility of 1,4-dihydroxy-9,10-anthraquinone (AQ) in aqueous methanol solution without and with the salts sodium chloride and potassium chloride at 298.15 K under barometric pressure by ‘spectroscopic method’. The relative solubility data, salting-in/out constants have been calculated to justify the trends of solubility of AQ in aqueous methanol in the presence of salts. Different solvent parameters at standard temperature have been measured. With the help of the solubility data, the solvation energies of solutions (ΔGs0) and accordingly the transfer Gibbs energetics have been determined to discuss the chemical stability of AQ in aqueous methanol solutions.