Several years ago a modified UNIFAC (Dortmund, FRG) method was proposed, which shows various advantages when compared with the group contribution methods UNIFAC or ASOG; the latter are used worldwide for the synthesis and design of rectification processes. These advantages were reached by using a modified combinatorial part and by using a large data base to fit temperature-dependent group interaction parameters simultaneously to vapor-liquid equilibrium (VLE), liquid-liquid equilibrium (LLE), h E , and γ ∞ data. The main advantages of the modified UNIFAC method are a better description of the temperature dependence and the real behavior in the dilute region and that it can be applied more reliably for systems involving molecules very different in size. To increase the range of this applicability, the temperature-dependent group interaction parameters of the modified UNIFAC has been fitted for 45 main groups using phase equilibrium information (VLE, h E , γ ∞, LLE) stored in the Dortmund Data Bank. A comprehensive comparison with the results of other group contribution methods confirms the high reliability of the modified UNIFAC (Dortmund) method

A modified UNIFAC model. 2. Present parameter matrix and results for different thermodynamic properties

PSRK: A Group Contribution Equation of State Based on UNIFAC

The development of van der Waals cubic equations of state and their application to the correlation and prediction of phase equilibrium properties is presented and analyzed. The discussion starts with a brief account of the contributions to equation of state development during the years before van der Waals. Then, the original equation proposed in the celebrated thesis of van der Waals in 1873 and its tremendous importance in describing fluid behavior are analyzed. A chronological critical walk through the most important contributions during the first part of the 1900s is made, to arrive at the proposal that I consider to be the most outstanding since van der Waals:  the equation proposed by Redlich and Kwong in 1949. The contributions after Redlich and Kwong to the modern development of equations of state and the most recent equations proposed in the literature are analyzed. The application of cubic equations of state to mixtures and the development of mixing rules is put in a proper perspective, and the ...

The state of the cubic equations of state

Quantitative Correlation of Physical and Chemical Properties with Chemical Structure: Utility for Prediction

This paper presents a review of the research on the Kalina cycle, including the description of the Kalina cycle, the comparison of the Rankine and Kalina cycle, energy and exergy analysis on the Kalina cycle, different Kalina systems and their different applications. Moreover, different correlations for calculating thermodynamic properties of ammonia–water mixture are screened and discussed. In the end, some technique concerns on ammonia–water mixture, i.e., stability, environmental impacts, safety and corrosion problem etc are also discussed.

A review of research on the Kalina cycle

To extend the applicable systems and improve the accuracy of ASOG (Analytical Solution of Groups), which is a predictive method for activity coefficients, the group interaction parameters have been newly determined and some of those reported are revised. The group interaction parameters are increased to 341 group pairs consisting of 43 groups against the previous 31 groups and 138 group pairs. Twelve groups are newly added: pyridine, furfural, ACRY, Cl (C=C), DMSO, NMP, C≡C, SH, DMF, ethanediol, DEG, and sulfolane. The parameters for the previous 31 groups are revised for 10 of those groups: C=C, ArOH, GOH, O, CHO, CON, CN, ArNH2, Cl, and ArCl. The parameters are then extended by providing missing values for others among the 31 previous groups. The temperature range of experimental data used for parameter determination is 293 K to 423 K.

Determination of new ASOG parameters.

Measuring methods of infinite dilution activity coefficients and a database for systems including water

Vapor-liquid equilibrium data for methanol+ethanol+water and its three constituent binary systems methanol+ethanol, ethanol+water, and methanol+water were measured at 101.3 kPa using a liquid-vapor ebullition-type equilibrium still. The experimental binary data were correlated by the NRTL equation. The ternary system methanol+ethanol+water was predicted by means of the binary NRTL parameters with good accuracy

Isobaric vapor-liquid equilibria for methanol + ethanol + water and the three constituent binary systems

Thermodynamic consistency test of vapor-liquid equilibrium data: - Methanol ∼ water, benzene ∼ cyclohexane and ethyl methyl ketone ∼ water -

Isothermal vapor-liquid equilibria were measured for the ternary system methanol + ethanol + water and its constituent binary systems of methanol + water and ethanol + water at 323.15, 328.15, and 333.15 K. The apparatus that was used made it possible to control the measured temperature and total pressure by computer. The experimental binary data were correlated by the NRTL equation. The ternary system was predicted using the binary NRTL parameters with good accuracy.

Kazuo Kojima

Papers

Determination of new ASOG parameters.

Measuring methods of infinite dilution activity coefficients and a database for systems including water

Isobaric vapor-liquid equilibria for methanol + ethanol + water and the three constituent binary systems

Thermodynamic consistency test of vapor-liquid equilibrium data: - Methanol ∼ water, benzene ∼ cyclohexane and ethyl methyl ketone ∼ water -

Isothermal Vapor-Liquid Equilibria for Methanol + Ethanol + Water, Methanol + Water, and Ethanol + Water