Ali Haghtalab - Department of Chemical Engineering, Tarbiat Modares University, P.O. Box: ۱۴۱۱۵-۱۴۳, Tehran, Iran
Abolfazl Shojaeian

Most of the thermodynamic properties have strong dependency on temperature. Based on this matter the cubic square well (CSW) equation of state is modified by applying temperaturedependence for two parameters of this model. The temperature dependency is applied on hard corediameter and square well potential depth by two different cases. The difference between these cases are in temperature dependent equation that is used for square well potential depth. Themodified cubic square well EOS (M-CSW) are used for correlation of the vapour pressure, liquid density and prediction of the vapour molar volume of 36 Pure component with more than 650 datapoints. The modified cubic square well EOS has the same number of adjustable parameters, but the results show that is more accurate than the original version. The results demonstrate thatpresent modification improved the predictability of the model and correlate vapour molar volume more accurate

Modified CSW EOS, Equation of State, Square-Well Potential, Temperature dependent parameters