Linear variation of isochoric lines and determination of phase transitions in size asymmetric mixtures
A. VELEZ; S. ESPINOSA; S. PEREDA; E.A. BRIGNOLE
Anales de la Academia Nacional de Ciencias Exactas, Físicas y Naturales de Buenos Aires
ACADEMIA NACIONAL DE CIENCIAS EXACTAS FÍSICAS Y NATURALES
Lugar: Buenos Aires; Año: 2009 vol. 21 p. 49 - 52
The study of isochoric lines for the determination of densities of reactive mixtures provided strong evidence that the change in the slope of the pressure vs. temperature lines can be used to determine the phase boundaries of size asymmetric mixtures. This type of mixtures is important for sustainable processes using supercritical fluids as green solvents. It was found that isochoric pressure vs. temperature lines, in the gas-liquid region, are virtually linear. This method can be applied to binary or multicomponent mixtures. Based on this a methodology was developed to determine phase transition conditions when rather extreme values of pressure and temperature must be investigated. The observed experimental behavior is also supported by the computation of pressure vs. temperature variation of isochoric flashes for asymmetric mixtures, using different equations of state.