CRITICAL LINES IN BINARY MIXTURES OF COMPONENTS WITH MULTIPLE CRITICAL POINTS

The principal aim of this work is a comprehensive analysis of the fluid phase behavior of binary fluid mixtures via the van der Waals like equation of state (EoS) which has a multiplicity of critical points in metastable region. We test the modified van der Waals equation of state (MVDW) proposed by Skibinski et al. (2004) which displays a complex phase behavior including three critical points and identifies four fluid phases (gas, low density liquid (LDL), high density liquid (HDL), and very high density liquid (VHDL)). An improvement of repulsive part doesn't change a topological picture of phase behavior in the wide range of thermodynamic variables. The van der Waals attractive interaction and excluded volume for mixture are calculated from classical mixing rules. Critical lines in binary mixtures of type III of phase behavior in which the components exhibit polyamorphism are calculated and a continuity of fluid-fluid critical line at high pressure is observed.