Previously reported ion-specific equation coefficients for both the Abraham general solvation model and Goss modified Abraham model are updated using recently measured activity coefficient, gas chromatographic retention factor, and solubility data for solutes dissolved in room temperature ionic liquids (RTILs). Reported for the first time are equation coefficients for 1-propyl-2,3-dimethylimidazolium cation, and octylsulfate and thiocyanate anions. In total nine sets of cation-specific and eight sets of anion-specific equation coefficients have been determined for each model. The derived correlations describe the 976 experimental gas-to-RTIL partition coefficients to within a standard deviation of 0.12 log units and the 955 experimental water-to-RTIL partitions to within a standard deviation of 0.15 log units.

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Water-to-polydimethylsiloxane (PDMS) and gas-to-PDMS sorption coefficients have been compiled for 170 gaseous and organic solutes. Both sets of sorption coefficients were analyzed using the Abraham solvation parameter model. Correlations were obtained for both "dry" headspace solid-phase microextraction and conventional "wet" PDMS coated surfaces. The derived equations correlated the experimental water-to-PDMS and gas-to-PDMS data to better than 0.17 and 0.18 log units, respectively. In the case of the gas-to-PDMS sorption coefficients, the experimental values spanned a range of approximately 11 log units.

Experimental partition coefficient data have been compiled from the published literature for the water/methyl acetate, water/ethyl acetate and water/butyl acetate partition systems, log P data, and for the gas/methyl acetate, gas/ethyl acetate and gas/butyl acetate partition systems, log K data. Application of the Abraham solvation parameter model to the sets of partition coefficients leads to equations that correlate the log P data and log K data to 0.18 log units for the three dry alkyl acetate solvents. Slightly larger deviations were noted for solute partition into both wet ethyl acetate and wet butyl acetate. The derived correlations were validated using training set and test set analyses.

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2008) Computation methodology for determining Abraham solute descriptors from limited experimental data by combining Abraham model and Goss-modified Abraham model correlations, Physics and Chemistry A new computation methodology is proposed for calculating the Abraham solute descriptors. The proposed method combines correlations based on both the Abraham model and the Goss-modified version of the Abraham model. The computation methodology is illustrated using published solubility and partition data for benzil in a wide range of organic solvent systems. Calculated solute descriptors back-calculate the observed experimental values to 0.119 log units. The proposed method of using both the Abraham model and the Goss-modified Abraham model correlations significantly increases the number of available equations that can be used in the solute descriptor determination.

Experimental solubilities are reported for anthracene dissolved in ternary cyclohexane + 1-propanol + 2-methyl-1-propanol, cyclohexane + 2-propanol + 2-methyl-1-propanol, cyclohexane + 1-butanol + 2-methyl-1-propanol, and cyclohexane + 2-butanol + 2-methyl-1-propanol solvent mixtures at 298.15 K and atmospheric pressure. For each of the four ternary solvent systems, 19 compositions were studied. Results of these measurements are used to test the predictive ability of the ternary solvent form of the Jouyban-Acree model (also referred to in the literature as the Combined NIMS/Redlich-Kister model).Computations showed that the model predicted the observed solubility behavior to within an overall average absolute relative percentage deviation of about 1.3.

Experimental solubilities are reported for anthracene dissolved in ternary heptane + 1-propanol + 1-pentanol, heptane + 2-propanol + 1-pentanol, heptane + 1-butanol + 1-pentanol, and heptane + 2-butanol + 1-pentanol solvent mixtures at 298.15 K and atmospheric pressure. For each of the four ternary solvent systems, 19 compositions were studied. Results of these measurements are used to test the predictive ability of the ternary solvent form of the Jouyban-Acree model (also referred to in the literature as the Combined NIMS/ Redlich-Kister model). Computations showed that the model predicted the observed solubility behavior to within an overall average absolute relative percentage deviation of about 1.8.