New pure component parameters are presented for the MOSCED limiting activity coefficient model for 133 solvents with an absolute average deviation of 10.6% to experimental literature data. The MOSCED model has been applied to solid-liquid equilibria correlation and compared with the experimental data available in the literature. The correlation of solubility of 26 solids in organic solvents has an average absolute deviation of 25%. This compares favorably to the prediction of the modified UNIFAC model.

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Vapor−liquid equilibria, molar volumes, and volume expansion for several binary mixtures of organic solvents with carbon dioxide have been determined using a visual synthetic technique at temperatures from (298 to 333) K. The binary vapor−liquid equilibrium and saturated liquid molar volume of CO2 + acetone, + acetonitrile, + dichloromethane, + nitromethane, + N-methyl-2-pyrrolidone, + perfluorohexane, + 2-propanol, + tetrahydrofuran, + toluene, and + 2,2,2-trifluoroethanol were measured at temperatures from (298.2 to 333.2) K. The VLE correlated well using the Patel−Teja equation of state with Mathias−Klotz−Prausnitz mixing rules. The solubility of CO2 in the various solvents is explained by considering the intermolecular interactions of CO2 in solution.

A novel class of tunable solvents facilitates recycle of homogeneous catalysts for both economic and environmental advantages. In a mixed organic-aqueous tunable solvent (OATS), reactions between water-soluble catalysts and moderately hydrophobic substrates can be run homogeneously, with subsequent phase separation for product purification and catalyst reuse. One example demonstrated is the dimethyl ether (DME)-water system, which has been employed as a benign alternative to organic solvents for alcohol dehydrogenase (ADH)-catalyzed reduction of hydrophobic ketones coupled with regeneration of the cofactor NADH. We also show the feasibility of a biphasic DME-water separation scheme to couple with the biocatalytic reaction. The subsequent downstream processing offers the advantages of easily isolating water-insoluble products from the aqueous phase and recycling enzyme-cofactor. Other OATS systems are discussed where the preferential dissolution of modest pressures of CO 2 causes phase separations, which result in very large distribution coefficients of target molecules in the biphasic organicaqueous system, with substantial promise as tunable solvents for biocatalysis.

We seek an improved methodology for the design of solvents and solvent mixtures for separations, especially purification of solids by crystallization. This paper reports new data for the solubility of four multifunctional solids: 3-nitrophthalimide, 5-fluoroisatin, 2-amino-5-nitrobenzophenone, and benzimidazole. The heat of fusion for each solid was measured along with the solubility in several pure and mixed solvents at 283, 298, and 313 K. These data were used to determine new parameters for the MOSCED model for these solids, and those parameters were then used to predict the solid solubility in mixed solvents. The ability to use thermodynamic models to predict solubility of complex solutes provides a new paradigm for the selection of both pure and mixed solvents.