PREDICTION OF ONE-COMPONENT VAPOR-LIQUID-EQUILIBRIA FROM THE TRIPLE POINT TO THE CRITICAL-POINT USING A SIMPLIFIED PERTURBED HARD-CHAIN THEORY EQUATION OF STATE

A simplified perturbed hard-chain theory (SPHCT) equation of state is used to predict the vapour-liquid equilibria of 69 one-component fluid s including n-alkanes, n-alkenes, n-alkynes, n-alkanols, polyatomic po lar molecules and noble gases. A procedure is reported for obtaining t he equation of state parameters from critical properties and the acent ric factor. The predicted vapour pressures are compared with experimen tal data over a wide range of temperature, which in many cases, extend s from the triple point to the critical point of the fluid. The calcul ations are also compared with results obtained using the Christoforako s-Franck equation of state. It is concluded that the hard-chain theory methodology represents vapour-liquid equilibria of non-spherical mole cules more accurately than hard-sphere approaches. The average absolut e deviation in the vapour pressure predicted by the SPHCT equation of state is typically within the range of 5%-15%.