Thermodynamic study of CO2-organic compound interaction at high pressures and temperatures

The energetics associated with chemical and physical interactions involving supercritical fluids are studied. Emphasis was placed on reactions involving CO2, Freons, and hydrocarbons. Heats of mixing were measured (H/sup E/) for selected binary systems at temperatures and pressures in the vicinity of the critical points of one or both of the components. These experimental H/sup E/ data are incorporated into appropriate equations of state or modified equations of state in order to describe the variations in H/sup E/ with temperature and pressure. In addition, H/sup E/ data in critical regions provide an excellent test for the validity of the equations used to describe these data. Several systems which illustrate these principles are presented and discussed in this report. These systems are (propane + CF2Cl2), (CO2 + pyridine), CHF2Cl + N,N-dimethylacetamide), (CHF2Cl + 2,3 dimethylbutane), (CF2Cl12 + N,N-dimethylacetamide), and (CF2Cl2 + ethane).