Infinite dilution coefficient hydrocarbon

Pieratti et ol. (1955) have developed correlations for the prediction of the activity coefficients at infinite dilution for systems containing water, hydrocarbons and some other organic compounds. Their method, and the data needed for predictions, is described by Treybal (1963) and Reid et al. (1987). 

In many publications, the activity coefficients at infinite dilution / j have been determined for alkanes, alk-l-enes, alk-l-ynes, cycloalkanes, aromatic hydrocarbons, carbon tetrachloride, and methanol in the IL at different temperatures. Figure 1.15 presents a plot of the activity coefficients, xrs against chain length, n of hydrocarbons n-alkanes, alk-l-enes, alk-l-ynes, and cycloalkanes for [C6CiIm][Tf2N] [183]. 

Heintz, A., Kulikov, D.V., and Verevkin, S.R, Thermodynamic properties of mixtures containing ionic liquids. 2. Activity coefficients at infinite dilution of hydrocarbon and polar solutes in l-methyl-3-ethyl-imidazolium bis(trifluoromethyl-sulfonyl)amide and in l,2-dimethyl-3-ethyl-imidazolium bis(trifluoromethyl-sulfonyl)amide using gas-liquid chromatography, /. Chem. Eng. Data, 47, 894, 2002. 

Smiley191 has measured gas-liquid retention volumes to obtain values for the activity coefficients at infinite dilution for eight different five-carbon hydrocarbons in NMA. The activity coefficients were determined at 40, 70, and 100 °C and, from the temperature dependence, values for the partial molar heats of solution were calculated. Frost and Bittrich192) have reported limiting activity coefficients of benzene and cyclohexane in NMA at 25 and 50 °C. 

The correlation volume and the energy of interaction between two unlike molecules in the systems HFB—B were calculated as for the binary aqueous solutions of alcohols and hydrocarbons, using eqs 19—20 and expressions for the local compositions and activity coefficients at infinite dilution. It should be however emphasized that the calculation procedure is not very accurate when the activity coefficients at infinite dilution are close to unity. For the system HFB (1)—B (2) at 40 °C, =... 

By coupling the equations obtained in the previous section with expressions for the activity coefficient at infinite dilution (Shulgin Ruckenstein, 1999a) one could calculate the correlation volumes of alcohol and hydrocarbon molecules in (infinitely) dilute aqueous solutions. The results obtained (Shulgin Ruckenstein, 1999a) were in good agreement with experimental data. 

Tsonopoulos and Pransnitz (27) have reported that the hydrocarbon infinite dilution coefficient, y00, is the appropriate quantity for correlating the aqueous solubilities of hydrocarbons. They, along with Leinonen et al. (23) and Pierotti et al. (28) have successfully correlated y00 with carbon number, molar volume, and degree of branching. Recently MacKay and Shiu (26) have correlated the hydrocarbon infinite dilution coefficients of 32 aromatic hydrocarbons (using the supercooled standard state) with carbon number. From this relationship, they derived a... 

DO1 Domanska, U. and Zolek-Tryznowska, Z., Measurements of mass-fraction activity coefficient at infinite dilution of aliphatic and aromatic hydrocarbons, thiophene, alcohols, water, ethers, and ketones in hyperbranched polymer, Boltom H2004, using inverse gas chromatography, J. Chem. Thermodyn., 42, 363, 2010. 

Furthermore, poor results are obtained for the solubilities and activity coefficients at infinite dilution of alkanes or naphthenes in water. This was accepted by the developers of modified UNIFAC to achieve reliable VLE results, for example, for alcohol/water systems. The reason was that starting from experimental g -values of approx. 250000 for n-hexane in water at room temperature it was not possible to fit alcohol-water parameters which deliver y -values for hexanol in water of 800 and at the same time describe the azeotropic composition of ethanol and higher alcohols with water properly and obtain homogeneous behavior for alcohol-water systems up to C3-alcohols and heterogeneous behavior starting from C4-alcohols. To allow for a prediction of hydrocarbon solubilities in water an empirical relation was developed [61, 62], which allows the estimation of the solubilities of hydrocarbons in water and of water in hydrocarbons (see below). 

As mentioned before, unsatisfying results of modified UNIFAC are obtained for the activity coefficients at infinite dilution and the solubilities of hydrocarbons in water. Typical results are given in Table 5.17. From the listed solubilities it can be... 

Fischer, K. Gmehling, J. Vapor-hquid equihbria, activity coefficients at infinite dilution and heats of mixing for mixtures of N-methylpyrrohdone-2 with C5 or C6 hydrocarbons and for hydrocarbon mixtures Fluid Phase Equilib. 1996,119,113-130... 

Liquids. 6. Activity Coefficients at Infinite Dilution of Hydrocarbons, Alcohols, Esters, and Aldehydes in l-Methyl-3-octyl-imidazolium Tetrafluoroborate Using Gas-Liquid Chromatography. J. Chem. Eng. Data 2005, 50,1515-1519. 

Coefficients at Infinite Dilution of Hydrocarbons, Alkylbenzenes, and Alcohols in the Paramagnetic Ionic Liquid l-Butyl-3-methyl-imidazolium Tetrachloridoferrate(III) using Gas-Liquid Chromatography.. Chem. Thermodyn. 2009,41, 330-333. 

Haines, R.L.S., Sandler, S.L. (1995) Aqueous solubilities and infinite dilution activity coefficients of several polycyclic aromatic hydrocarbons. J. Chem. Eng. Data 40, 835-836. 

Wright, D.A., Sandler, S.I., and DeVoll, D. Infinite dilution activity coefficients and solubilities of halogenated hydrocarbons in water at ambient temperatures. Environ. Scl. Technol, 26(9) 1828-1831, 1992. 

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