Abstract: Experimental solubility data are reported for anthracene, biphenyl, benzil, benzoin, 1-chloroanthraquinone, phenothiazine, pyrene, salicylamide, thioxanthen-9-one, xanthene, benzoic acid, 4-tert-bu...

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Topics: Benzoin (62%), Benzil (57%), Benzoic acid (57%) ... show more

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5 results found

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Jennifer Huang^{1}, Shrika Eddula^{1}, Priya Tirumala^{1}, Theresa Casillas^{1} +2 more•Institutions (2)

Abstract: A search of the published chemical and engineering literature found enthalpy of solution data for an additional 71, 39 and 46 organic compounds dissolved in heptane, cyclohexane and N,N-dimethylfor...

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Topics: Enthalpy change of solution (59%), Heptane (58%), Solvation (56%) ... show more

7 Citations

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Abstract: Enthalpies of solution at infinite dilution have been determined for 2-propanol, ethylene glycol, 1,3-butanediol, 1,4-butanediol, phenol, 1-naphthol, 3-nitrophenol, 4-nitrophenol, 4-chlorophenol, and formamide dissolved in N-methylformamide, 2-pyrrolidone, and N-methylpyrrolidone at 298.15 K, as well as for N-methylformamide dissolved in 2-pyrrolidone and N-methylpyrrolidone, based on solution calorimetric measurements. Results of our experimental measurements, combined with published literature data, have been used to derive Abraham model expressions for predicting the enthalpies of solvation of solutes dissolved in the three fore-mentioned amide solvents. Our derived mathematical expressions back-calculated the observed enthalpy of solvation data to within a standard deviation of 3.1 kJ mol−1 or less.

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Topics: Solvation (57%), Formamide (51%), N-Methylformamide (51%)

6 Citations

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Brittani Churchill^{1}, Theresa Casillas^{1}, William E. Acree^{1}, Michael H. Abraham^{2}•Institutions (2)

Abstract: Abraham model correlations are derived for describing gas-to-ionic liquid and water-to-ionic liquid partition coefficients from published experimental data for solutes dissolved in both N-ethyl-N-m...

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Topics: Solvation (53%)

4 Citations

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Abstract: Polyparameter Linear Free Energy Relationships (PPLFERs) are an empirical tool used to predict the equilibrium partitioning of solutes between two phases, referred to as a system. There are experimentally determined solute descriptors for thousands of chemicals, but there are only on the order of 100 systems with calibrated system parameters, the majority of which are solvents and environmental matrixes in equilibrium with air or water. The goal of this work is to create empirical regressions which use the much more numerous solute descriptors to predict the system parameters of systems which have not yet been calibrated due to a lack of partitioning data. The special case of liquid solvents in equilibrium with air is the focus of this work because this is the case in which the relationship between solute and solvent properties is most clear. First a consistent dataset of PPLFER equations was compiled using partition coefficient data from the literature to recalibrate equations for solvent-air partitioning into the Goss form (Goss, K.-U. 2005) for 89 solvents including water. All 89 solvents have also solute descriptors available in a database curated for this work which describe their behaviour as solutes. The pool of descriptors drawn from to create the empirical regressions were the solute descriptors of the solvents normalized to McGowan volume (V), along with interaction parameters between the normalized descriptors. An applicability domain (AD) for the empirical regressions was defined using leverage to measure similarity to the training dataset of solvents, and solvents in the AD typically had lower RMSE for predictions. Some of the empirical regressions for the six system parameters have good predictive power (s, a, b, c) while others are only adequate (v, l). However, when these equations are combined to predict partition coefficients there is a significant cancellation of error and when predicting partition coefficients in an external validation dataset the RMSE is in the range 0.30–0.35. The empirical regressions combined with the PPLFER equations and solvent density can also be used to predict vapor pressures as an additional external validation. Predictions for a dataset of vapor pressures from the literature had an RMSE of 0.26–0.75. Analysing and comparing the results from these two external validation datasets the RMSE for predicting datasets of partition coefficients for arbitrary solutes in arbitrary systems of solvents in equilibrium with air is estimated to be 0.66 on average.

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1 Citations

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Katherine Smart^{1}, Erin Connolly^{1}, Libby Ocon^{1}, Teresa D. Golden^{1} +2 more•Institutions (2)

Abstract: Experimental water-to-methyl ethyl ketone partition coefficients have been determined for 34 different organic solutes at ambient room temperature based on gas–liquid chromatographic measurements

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Topics: Partition coefficient (55%), Partition (number theory) (50%), Ketone (50%) ... show more

1 Citations

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90 results found

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Topics: Solvation (61%), High-performance liquid chromatography (57%), Gas chromatography (56%) ... show more

1,796 Citations

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Abstract: The use of gas-liquid chromatographic (GLC) retention data to obtain sets of solute descriptors is outlined, with reference to the schemes of Laffort and of Weckwerth. The method of Snyder and Dolan to obtain a set of solute descriptors from reverse phase high performance chromatographic (RP-HPLC) measurements is described. The work of Abraham on the construction of solvation parameters, or descriptors, from water-solvent partitions, GLC retention data and RP-HPLC data is considered in some detail. A comparison is made between the schemes of Laffort, Weckwerth and Abraham, and it is shown that the latter two yield exactly the same fits for a test data set of gas-methanol partition coefficients, although the distribution of chemical information amongst the terms in the multiple linear regressions is not quite the same. A comparison between the above 'experimental' descriptors and theoretical descriptors is made, and it is shown that the experimental Abraham and the theoretical Klamt descriptors encode almost the same chemical information. It is concluded that for processes that entail transfer of a solute from one phase to another, only a small number of solute descriptors, no more than five or six, is needed to provide a reasonably accurate analysis of the process.

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770 Citations

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Abstract: In the correlation of reversed-phase liquid chromatography capacity factors through the equation,
$$\log k' = log k'_0 + mV/100 + s\pi _2^* + b\beta _2 + a\alpha _2 $$
the use of McGowans characteristic volume, Vx, which can be trivially calculated, is entirely equivalent to the use of Leahy's computer-calculated intrinsic volumes, V1, for the cavity term mV/100. It is shown that for 209 gaseous, liquid, and solid solutes, the two sets of volumes are related through the equation,
$$V_1 = 0.597 + 0.6823 V_x $$
with a standard deviation of only 1.24cm3 mol−1, and a correlation coefficient of 0.9988.

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722 Citations

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Jeffrey Read^{1}, K. Mutolo^{1}, Matthew H. Ervin^{1}, Wishvender K. Behl^{1} +3 more•Institutions (1)

Abstract: The oxygen transport properties of several organic electrolytes were characterized through measurements of oxygen solubility and electrolyte viscosity. Oxygen diffusion coefficients were calculated from electrolyte viscosities using the Stokes-Einstein relation. Oxygen solubility, electrolyte viscosity, and oxygen partial pressure were all directly correlated to discharge capacity and rate capability. Substantial improvement in cell performance was achieved through electrolyte optimization and increased oxygen partial pressure. The concentration of oxygen in the electrode under discharge was calculated using a semi-infinite medium model with simultaneous diffusion and reaction. The model was used to explain the dependence of cell performance on oxygen transport in organic electrolyte. © 2003 The Electrochemical Society. All rights reserved.

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Topics: Oxygen transport (72%), Limiting oxygen concentration (63%), Oxygen (59%) ... show more

434 Citations

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Abstract: Additive models for the estimation of Abraham's molecular descriptors R2, π2H, Σα2H, Σβ2H, Σβ2O, and log L16 have been developed. For five of the six descriptors, one set of 81 atom and functional group fragments is capable of reproducing experimentally derived results with correlation coefficients ranging from 0.95 to 0.99. However, one descriptor, Σα2H, required an entirely separate set of 51 fragments to be developed, resulting in a correlation coefficient of 0.97. Of particular importance is the speed of calculation (approximately 700 molecules/min), allowing so-called “high-throughput screening”. Several applications of this model for molecules containing intramolecular interactions are discussed.

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Topics: Molecular descriptor (57%)

373 Citations