Determining activity coefficients of liquids in binary solutions: A new method

1970 ◽  
Vol 47 (12) ◽  
pp. 826 ◽  
Author(s):  
H. J. Arnikar ◽  
T. S. Rao ◽  
A. A. Bodhe
Keyword(s):  
Activity Coefficients ◽  
New Method ◽  
Binary Solutions

Limiting activity coefficients in dilute solutions of nonelectrolytes. II. Determination for polar–nonpolar and polar–polar binary mixtures, and the application of some solubility-parameter treatments

1986 ◽  
Vol 64 (1) ◽  
pp. 198-203 ◽  
Author(s):  
Shapour Afrashtehfar ◽  
Genille C. B. Cave
Keyword(s):  
Binary Mixture ◽  
Activity Coefficients ◽  
Vapor Phase ◽  
Solubility Parameter ◽  
Chromatographic Analysis ◽  
Dipole Interaction ◽  
The Other ◽  
Binary Solutions ◽  
Polar Components ◽  
Induced Dipole

Activity coefficients were determined at 293.15 K for the more dilute component in 24 binary solutions of nonelectrolytes, by gas-chromatographic analysis of the equilibrium vapor phase. One component of the binary mixture was either nitromethane, nitroethane, 1-nitropropane, 2-nitropropane, ethanenitrile, propanenitrile, ethyl ethanoate, or butyl ethanoate; and the other component was either heptane, 1-heptene, or 1,6-heptadiene.From the limiting activity coefficients of these components, some factors that affected their magnitude were identified. The values were also used to test the modifications of Prausnitz, Blanks, and Weimer, of Helpinstill and Van Winkle, and of Keller, Karger, and Snyder to the Scatchard–Hildebrand equation modified to accommodate polar components. In addition, the degree of constancy of the ratio of the dipole – induced dipole interaction parameter for a series of solutes in one solvent to that in another was considered.

scholarly journals Method for Estimating Activity Coefficients of Target Components in Poorly Specified Mixtures

2021 ◽  
Author(s):  
Fabian Jirasek ◽  
Jakob Burger ◽  
Hans Hasse
Keyword(s):  
Nmr Spectroscopy ◽  
Activity Coefficient ◽  
Activity Coefficients ◽  
New Method ◽  
Target Component ◽  
Test Cases ◽  
Group Contribution Method ◽  
Bioprocess Engineering ◽  
Separation Processes ◽  
Chemical Groups

Mixtures that contain a known target component but are otherwise poorly specified 15 are important in many fields. Previously, the activity of the target component, which is needed e.g. to design separation processes, could not be predicted in such mixtures. A method was developed to solve this problem. It combines a thermodynamic group contribution method for the activity coefficient with NMR spectroscopy, which is used for estimating the nature and amount of the different chemical groups in the mixture. The knowledge of the component 20 speciation of the mixture is not required. Test cases that are inspired by bioprocess engineering applications show that the new method gives surprisingly good results.

scholarly journals Technical note: Estimating aqueous solubilities and activity coefficients of mono- and <i>α</i>, <i>ω</i>-dicarboxylic acids using COSMO-RS-DARE

2020 ◽  
Author(s):  
Noora Hyttinen ◽  
Reyhaneh Heshmatnezhad ◽  
Jonas Elm ◽  
Theo Kurtén ◽  
Nønne L. Prisle
Keyword(s):  
Activity Coefficients ◽  
Equilibrium Constants ◽  
Hydrate Formation ◽  
Dicarboxylic Acids ◽  
Water Systems ◽  
Technical Note ◽  
Monocarboxylic Acids ◽  
Binary Solutions ◽  
Experimental Activity ◽  
Aqueous Solubilities

Abstract. We have used the COSMOtherm program to estimate activity coefficients and solubilities of mono- and α, ω-dicarboxylic acids, and water in binary acid-water systems. The deviation from ideality was found to be larger in the systems containing larger acids than in the systems containing smaller acids. We found a better agreement between estimated and experimental activity coefficients of monocarboxylic acids when the water clustering with a carboxylic acid and itself was taken into account using the dimerization, aggregation and reaction extension (COSMO-RS-DARE) of COSMOtherm. Based on effective equilibrium constants of different clustering reactions in the binary solutions, acid dimer formation is more dominant in systems containing larger dicarboxylic acids (C5–C8), while for monocarboxylic acids (C1–C6) and smaller dicarboxylic acids (C2–C4), hydrate formation is more favorable, especially in dilute solutions.

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