Vapor liquid equilibrium (VLE) data were measured for the nitrogen + carbon dioxide binary system at 220 and 240K and for the methane + carbon dioxide system at 219.26, 240, and 270K. Ternary VLE measurements were made for the system N2 + CH4 + CO2 at 220K and 6.080, 9.119 and 12.159 MPa, and 240K at 7.093, 9.119 and 12.159 MPa. The multifluid reference corresponding states method proposed by Teja and Rice was applied to VLE calculations and the results of this method for the binary and ternary systems were compared with the results of the Lee-Kesler corresponding states correlation and the Peng-Robinson equation of state. The multifluid and Lee-Kesler methods give comparable results for the constituent binaries of the N2 + CH4 + CO2 system. However, the multifluid model predictions for the ternary system were superior to the predictions of the Lee-Kesler method. The Peng-Robinson equation of state was found to be better than both corresponding states methods for both binary and ternart system VLE predictions. None of the methods produced good representation near the critical points of the binary and ternary systems.

Vapor-liquid equilibria were measured for the binary systems methane + carbon dioxide at 230, 250, and 270 K; methane + ethane at 210, 230, 270 K; and ethane + carbon dioxide at 210, 213, 230, 250 K. The ternary stystem methane + ethane + carbon dioxide was studied at 230 K over the pressure range 1.15 MPa to 6.59 MPa. The Peng-Robinson equation of state was used to model the experimental data with an accuracy sufficient for most engineering calculations Preliminary studies were made of the solid-liquid-vapor equilibria for the binary systems methane + carbon dioxide and ethane + carbon dioxide.

There were two major objectives for the work. The first objective was the experimental measurement and thermodynamic modeling of ternary vapor liquid equilibria of carbon dioxide systems of interest to the natural gas industry. The second objective was the measurement and thermodynamic modeling of solid-liquid-vapor phase behavior in binary carbon dixide systems.

Vapor-Liquid Equilibrium, Second Edition covers the theoretical principles and methods of calculation of equilibrium conditions from various experimental data and the elements of measuring technique, as well as the instruments for the direct determination of the equilibrium compositions of the liquid and vapor phases of the system. The book discusses the relations necessary for the thermodynamic treatment of the equilibrium between the liquid and vapor phase of a system; the concept of an ideal solution and auxiliary thermodynamic functions; and the activity and the activity coefficient. The text also describes vapor-liquid equilibrium in real systems (electrolytes and non-electrolytes) and in systems whose components (i.e. temperature, pressure, and composition of phases) mutually react according to several stoichiometric equations. The criteria of purity of substances and the methods of measuring temperature; low, medium, and high pressures; the pressures of the saturated vapors at given temperatures; and the boiling points at given pressures used in laboratory work in the field of vapor-liquid equilibrium are considered. The book also tackles the methods for the direct determination of equilibrium data (distillation, circulation, static, dew and bubble point, and flow methods). The text concludes with a review of the literature on the systems whose vapor-liquid equilibrium data had been measured and reported to the beginning of 1954. Workers in the chemical industry who deal with problems of distillation and rectification will find the book useful.