Journal of Chemical and Engineering Data, Vol.63, No.3, 801-811, 2018
Determination and Correlation for the Solubilities of Succinic Acid in Cyclohexanol plus Cyclohexanone plus Cyclohexane Solvent Mixtures
The solubilities of succinic acid in binary cyclohexanone + cyclohexanol solvent mixtures at 304.25-354.65 K, in binary cydohexane + cyclohexanol solvent mixtures at 300.15-346.15 K, in binary cyclohexane + cyclohexanone solvent mixtures at 297.65-351.25 K, and in ternary cyclohexanol + cyclohexanone + cyclohexane solvent mixtures at 306.95-343.15 K were determined by the synthetic method at atmospheric pressure. The experimental solubility data in binary solvent mixtures were correlated by the Apelblat equation and nonrandom two-liquid (NRTL) activity coefficient model, and the calculated solubility data by the models have a good agreement with the experimental data. Then, the solubilities of succinic acid in ternary cyclohexanol + cyclohexanone + cyclohexane solvent mixtures were predicted by the NRTL model and compared with the experimental solubility data. Finally, the solubilities of succinic acid in the three studied binary solvent mixtures were compared with the solubilities of glutaric acid and adipic acid in the same solvent systems at 303.15-343.15 K. The result shows that in the three studied solvent mixtures, glutaric acid with an odd number of carbon atoms is much more soluble than succinic acid and adipic acid with an even number of carbon atoms. The reasons for this "odd even effect" phenomenon are the interlayer packing of molecule chains and the twist of the carbon chains.