Journal of Chemical Thermodynamics, Vol.113, 71-80, 2017
Solubility and preferential solvation of 2-methyl-4-nitroaniline in mixed solvents of ethyl acetate plus (methanol, ethanol, n-propanol and isopropanol)
The mole fraction solubility of 2-methyl-4-nitroaniline in binary mixed solvents of (ethyl acetate + methanol), (ethyl acetate + ethanol), (ethyl acetate + n-propanol) and (ethyl acetate + isopropanol) was determined experimentally by using static method at temperatures from (278.15 to 313.15) K under atmospheric pressure. The solubility increased with increasing temperature and mass fraction of ethyl acetate. At the same temperature and mass fraction of ethyl acetate, the mole fraction solubility in (ethyl acetate + methanol) was greater than those in the other mixed solvents. The solubility values were correlated with Jouyban-Acree model, van't Hoff-Jouyban-Acree model, modified Apelblat-Jouyban-Acree model, Ma model, and Sun model. The maximum values of relative average deviations and root-mean square deviations were 0.47 x 10(-2) and 2.26 x 10(-4), respectively. Preferential solvation parameters of the solute were also derived by means of the inverse Kirkwood-Buff integrals (IKBI) method. The preferential solvation parameters delta x(1,3) are negative in alcohol-rich composition, but positive in intermediate and ethyl acetate-rich composition. The ethyl acetate action may be related to the breaking of the ordered structure of alcohol around the polar moieties of 2-methyl-4-nitroaniline. The positive delta x(1,3) values could be explained based on the higher acidic behaviour of 2-methyl-4-nitroaniline molecules interacting with the hydrogen acceptor groups present in ethyl acetate. This work expands the physicochemical information about solid in binary solvent mixtures. (C) 2017 Elsevier Ltd.
Keywords:2-Methyl-4-nitroaniline;Solubility;Thermodynamic model;Inverse Kirkwood-Buff integrals;Preferential solvation