Measurement and Correlation for Solubilities of Adipic Acid, Glutaric Acid, and Succinic Acid in Dimethyl Adipate + Methanol Mixtures

The solubilities of adipic acid, glutaric acid, and succinic acid in dimethyl adipate + methanol solvent mixtures were measured by the method of dynamic laser under 101.3 kPa. The mass fraction of dimethyl adipate in the solvent mixtures ranged from 0.0 to 1.0, and the temperature ranged from 283.95 to 328.15 K. It was found that with the increase of mass fraction for dimethyl adipate in mixed solvents, the measured solubilities of adipic acid, glutaric acid, and succinic acid would decrease at the same temperature, and with the gradually increase of temperature the measured solubilities of adipic acid, glutaric acid, and succinic acid would increase at the constant proportion solvent mixtures. The experimental data were correlated by the Apelblat model, λh model, and the modified nonrandom two liquid activity coefficient model. Results showed that the largest values of relative average deviation and root-mean-square deviations obtained by the three models were 4.49% and 0.35%, respectively. The three models were proven to give a good representation of the experimental solubilities results. The result of Akaike Information Criterion (AIC) analysis shows that the Apelblat model is the best model to correlate the solubilities of adipic acid and succinic acid and the λh model is the best model to correlate the solubilities of glutaric acid in dimethyl adipate + methanol mixed solvent.