Phase behavior of coal fluids: Data for correlation development: Final report for the period August 1, 1983 to January 31, 1987

The overall objective of the author's work is to develop accurate predictive methods for representation of vapor-liquid equilibria in systems encountered in coal-conversion processes. During the course of this project, solubility data were obtained on eighteen binary mixtures of the solute CO/sub 2/ or ethane in a series of paraffinic, naphthenic and aromatic solvents which included n-decane, n-dodecane, n-eicosane, n-octadecane, n-hexatriacontane, cyclohexane, trans-Decalin, benzene, naphthalene, phenanthrene and pyrene. Temperatures, pressures and solute mole fractions were in the general range of 313 to 423K, 0.3 to 12.0 MPa, and 0.05 to 0.60 mole fraction solute, respectively. The solubility data for either CO/sub 2/ or ethane in the paraffinic, naphthenic and aromatic solvents are described well by the Soave or Peng-Robinson equation of state (EOS). When one empirical interaction parameter, k/sub 12/, is used for each isotherm in each system, average errors in the predicted solubility are on the order of 0.01 to 0.02 mole fraction. The use of two interaction parameters per isotherm, k/sub 12/ and l/sub 12/, reduces the typical errors to 0.001 to 0.003. The experimental data obtained in the project can serve as an excellent basis for evaluation of parameters in any selected phase behavior model. The systematicmore » study of a series of solvents of the same molecular class can permit generalized correlations to be developed for the model parameters. For the equations of state studied in this work, convenient generalized correlations are presented for the interaction parameters of CO/sub 2/ or ethane in n-paraffins. To date, no equivalent generalizations have been developed for the naphthenic or aromatic solvents. 30 refs., 20 figs., 21 tabs.« less