CHEMICAL-REACTIONS AND PHASE-EQUILIBRIA OF MODEL HALOCARBONS AND SALTS IN SUBCRITICAL AND SUPERCRITICAL WATER (200-300-BAR, 100-600-DEGREES-C)

Experimental data and theoretical predictions of hydrolysis reaction k inetics of model halocarbons and phase equilibria of their associated neutralized salt reaction products are reported for a range of hydroth ermal conditions. Specifically, the results of a study of hydrolysis a nd oxidation of methylene chloride (CH2Cl2) to produce CO2, H2O, and H Cl as final mineralized products are presented. An analysis of hydroly sis kinetics and heat transfer was used to generate kinetic parameters for comparison with theoretical predictions based on a modified form of the Kirkwood solution model to show density dependent effects as a function of the dielectric strength of the reaction solvent medium. Ph ase equilibria data for the ternary NaCl-Na2SO4-H2O, system at 200 and 250 bar were measured and correlated. A modified form of the Anderko- Pitzer semi-empirical PVTx(i) model was used to predict equilibrium ph ase boundaries for the NaCl-H2O system at 210, 250, and 300 bar. Molec ular simulation results for the NaCl-H2O binary was used to illustrate changes in the solvation power of water as a function of density. (C) 1998 Elsevier Science B.V.