Application of the hole theory to study the p-v-t-x relations of the co2-ch4 and the co2-n2 systems
30 Jun 1972-Journal of Chemical Engineering of Japan (The Society of Chemical Engineers, Japan)-Vol. 5, Iss: 2, pp 107-111
TL;DR: In this paper, the hole theory is applied to represent the P-V-T-X relations at the phase boundary of the CO2-CH4 and the CO 2-N2 systems.
Abstract: The hole theory is applied to represent the P-V-T-X relations at the phase boundary of the CO2-CH4 and the CO2-N2 systems. As these systems contain super-critical components, Henderson''s approximation for free volume was simplified and adopted for these expanded solutions. An equation of state was derived by introducing two characteristic parameters, which were determined from the heat of vaporization and the saturated densities of liquid and vapor of the pure substance. The equation of state successfully explains the P-V-T-X relations of the above systems with the aid of combining rules for characteristic parameters.
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DSM1
TL;DR: In this paper, the straightforward two-component lattice gas treatment, shown by Trappeniers et al. to supply a qualitatively correct description of fluid phase behaviour, is applied here in an extended form so as to deal quantitatively with lowercritical demixing behaviour in alkane/polyethylene systems.
Abstract: The straightforward two-component lattice-gas treatment, shown byTrappeniers et al. to supply a qualitatively correct description of fluid phase behaviour, is applied here in an extended form so as to deal quantitatively with lowercritical demixing behaviour inn-alkane/polyethylene systems. Most of the parameters introduced have a clear physical meaning but, to achieve quantitative descriptions, some merely empirical parameters cannot be dispensed with. Their number is small, however, and the proposed procedure yields correct predictions of the location of lower critical miscibility gaps in temperature-concentration diagrams as well as their molar-mass- and pressure dependence. The parameters used are the interacting — surface areas of holes and sites occupied by either alkane or polymer segments (taken identical to the alkane units CH3 and CH2CH2), the molar hole volume (taken independent of mixture composition, pressure and temperature), the interaction energy between the structural units, and two empirical entropy correction parameters. No data on alkane/ polyethylene mixtures are needed and the treatment deals satisfactorily with pure substances and mixtures alike. Further improvements can be incorporated easily and application to more complicated polymer structures (long- and short chain branching) is well within the scope of the treatment.
107 citations
DSM1
TL;DR: In this article, the mean-field two-component lattice gas model was improved by introducing interacting surface areas and an empirical entropy of mixing parameter, which has proven to be well capable of describing almost quantitatively fluid-phase behaviour of non-polar and polar substances of low and high molar mass and mixtures thereof in large temperature and pressure ranges.
39 citations
TL;DR: In this article, a group-contribution equation of state (EOS) based on the hole theory has been developed to predict the phase equilibria of mixtures containing polar substances at high temperatures and pressures.
12 citations
DSM1
TL;DR: In this paper, the mean-field lattice gas model is used to describe and predict fluid phase behavior around critical points, particularly at the second critical endpoint, where the solute's heat of fusion and the location of its triplepoint compared with that of the critical point of the solvent.
Abstract: Solubility of solids in supercritical solvents is not essentially different from equilibrium crystallisation/solubility behaviour in normal liquids, except for the highly non-ideal nature of nearcritical fluid mixtures. It can be shown quite generally that interactions in the fluid phase play a predominant role both at the first and the second critical endpoints in a binary system. Further factors of importance, particularly at the second critical endpoint, are the solute's heat of fusion and the location of its triplepoint compared with that of the critical point of the solvent. In the separation of two solid components ternary critical endpoint behaviour and the location of the ternary eutectic further determine the selectivity of the extraction. The mean-field lattice-gas model provides a useful tool to describe and predict fluid phase behaviour around critical points.
9 citations
DSM1
TL;DR: The MFLG-model as discussed by the authors assumes the number of interacting contacts of each kind of polymer segment or molecule to be related to its specific surface area and introduces free volume in the polymer and thus can deal with upper and lower critical demixing and with volume and pressure variations of the system.
Abstract: The present MFLG-model assumes the number of interacting contacts of each kind of polymer segment or molecule to be related to its specific surface area. The model further introduces free volume in the polymer and thus can deal with upper- and lower critical demixing and with volume and pressure variations of the system.
1 citations
References
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Book•
01 Jan 1954
TL;DR: Molecular theory of gases and liquids as mentioned in this paper, molecular theory of gas and liquids, Molecular theory of liquid and gas, molecular theories of gases, and liquid theory of liquids, مرکز
Abstract: Molecular theory of gases and liquids , Molecular theory of gases and liquids , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی
11,807 citations
Book•
01 Jan 1969
TL;DR: In this article, the authors introduce the notion of uniformity of intensive potentials as a criterion of phase equilibrium, and propose a model for solubilities of solids in liquid mixtures.
Abstract: 1. The Phase Equilibrium Problem. 2. Classical Thermodynamics of Phase Equilibria. 3. Thermodynamic Properties from Volumetric Data. 4. Intermolecular Forces, Corresponding States and Osmotic Systems. 5. Fugacities in Gas Mixtures. 6. Fugacities in Liquid Mixtures: Excess Functions. 7. Fugacities in Liquid Mixtures: Models and Theories of Solutions. 8. Polymers: Solutions, Blends, Membranes, and Gels. 9. Electrolyte Solutions. 10. Solubilities of Gases in Liquids. 11. Solubilities of Solids in Liquids. 12. High-Pressure Phase Equilibria. Appendix A. Uniformity of Intensive Potentials as a Criterion of Phase Equilibrium. Appendix B. A Brief Introduction to Statistical Thermodynamics. Appendix C. Virial Coefficients for Quantum Gases. Appendix D. The Gibbs-Duhem Equation. Appendix E. Liquid-Liquid Equilibria in Binary and Multicomponent Systems. Appendix F. Estimation of Activity Coefficients. Appendix G. A General Theorem for Mixtures with Associating or Solvating Molecules. Appendix H. Brief Introduction to Perturbation Theory of Dense Fluids. Appendix I. The Ion-Interaction Model of Pitzer for Multielectrolyte Solutions. Appendix J. Conversion Factors and Constants. Index.
4,550 citations