Measurement of large infinite dilution activity coefficients of nonelectrolytes in water by inert gas stripping and gas chromatography

Abstract

An inert gas stripping gas chromatography method was described for the determination of infinite dilution activity coefficients ( ^) of organic compounds in water. The infinite dilution activity coefficients for 31 compounds including many halogenated and aromatic compounds were measured. In general, the y% values measured by gas stripping are in very good agreement with y% values estimated from the inverse solubilities and other experimental measurements. This suggests that when there is no directly measured data available, y^v alues estimated from the inverse of solubility can be used for the development and test of the models predicting limiting activity coefficients. A major advantage of this method relative to headspace gas chromatography that improves its precision and accuracy is the fact that the absolute detector response is unimportant. The detector only needs to be linear.

Determination of Air−Water Partitioning of Volatile Halogenated Hydrocarbons by the Inert Gas Stripping Method

“…Recent careful measurements of limiting activity coefficients for some halocarbons in water (Barr and Newsham, 1987;Cooling et al, 1992;Tse et al, 1992;Wright et al, 1992;Li et al, 1993) have yielded results of rather higher reliability. Since then, the IGS technique has been applied to a great variety of systems, the experimental setup and procedure being further developed and modified to extend its applicability (Mackay et al, 1979;Endler et al, 1985;Richon et al, 1985;Elsner et al, 1986;Wobst and Hradetzky, 1988;Li et al, 1993). The purpose of this work is to report new measurements of air-water partitioning carried out for 21 selected chlorinated and brominated hydrocarbons using the inert gas stripping method and compare the results with available literature data.…”

Compilation and Correlation of Limiting Activity Coefficients of Nonelectrolytes in Water

“…b References: (1) Li, 1992a; (2) Li et al, 1993a; (3) Barr and Newsham, 1987; (4) Dallas, 1993;(5) Mash and Pemberton, 1980;(6) Mel'der and Ebber, 1978; (7) Abraham et al, 1974;(8) Kohn, 1988;(9) Gillespie et al, 1985; (10) Wright et al, 1987;(11) Sorenson and Arit, 1979;(12) Macedo and Rasmusen, 1987;(13) Yaws et al, 1990a;(14) Yaws et al, 1990b;(15) Shaw, 1989. c (11) …”

Correlation and comparison of the infinite dilution activity coefficients in aqueous and organic mixtures from a modified excess Gibbs energy model

“…The ∆ parameter for a homologous series of solutes in a specific solvent is again a linear function of the refractive index of the pure solute, as written in Eq. (19). The numerical values of parameters for α and β for these non-aqueous systems are listed in Table 5.…”