Gibbs free energy

Choline chloride

Chromatography

Solubility

Enthalpy

UNIQUAC

Non-random two-liquid model

Inorganic chemistry

Dissolution

Thermodynamics

Physics

Chloride

Organic chemistry

Alloy

Activity coefficient

Eutectic system

Aqueous solution

Molar solubility

Chemistry

Fluid Phase Equilibria

The aqueous solubility of acetaminophen (ACP) in some choline chloride (ChCl) based deep eutectic solvents (DESs) with urea, oxalic acid and malonic acid as neoteric green solvents were measured up to 0.90 wt fraction of DESs at T = (293.15–318.15) K and at atmospheric pressure. The solubility in these solvents increased more than forty–fold with increasing the weight fraction of DESs, especially in DES containing malonic acid. The solubility data were accurately correlated by the NRTL, Wilson and UNIQUAC activity coefficient models. Also, to describe the thermodynamic behavior of ACP in the aqueous DES solutions, the thermodynamic functions, Gibbs energy, enthalpy, and entropy of dissolution and mixing were obtained by using the van't Hoff and Gibbs equations. The results indicate that the main contribution to the solubility of ACP in the aqueous DES solutions is enthalpic.

Experimental determination and correlation of acetaminophen solubility in aqueous solutions of choline chloride based deep eutectic solvents at various temperatures