# The Law of Corresponding States for Hydrocarbons: the Two-Phase Region

Requires a Wolfram Notebook System

Interact on desktop, mobile and cloud with the free Wolfram CDF Player or other Wolfram Language products.

Requires a Wolfram Notebook System

Edit on desktop, mobile and cloud with any Wolfram Language product.

Consider the following six chemical species: ethane, propane, -butane, -butane, -pentane, and -hexane. For each compound, this Demonstration uses arc-length continuation to plot (1) the compressibility factor versus reduced temperature for user-set values of the reduced pressure , or (2) the compressibility factor versus reduced pressure for user-set values of the reduced temperature . You can choose between two equations of state for EOS; namely the Soave–Redlich–Kwong EOS or the Peng–Robinson EOS (see the Details section).

[more]
Contributed by: Housam Binous, Nayef M. Alsaifi, Ali Kh. Al-Matar, and Brian G. Higgins (April 2014)

Open content licensed under CC BY-NC-SA

## Snapshots

## Details

In the Soave–Redlich–Kwong (SRK) equation of state, the compressibility factor occurs as a solution of the cubic equation

,

where and , with , *, *, and .

In the Peng–Robinson (PR) equation of state, the compressibility factor occurs as a solution of the cubic equation

,

where and , with , *, *, and .

In the equations given above, is the acentric factor, and are the critical temperature and pressure, and is the reduced pressure.

Reference

[1] W.-G. Dong and J. H. Lienhard, "Corresponding States Correlation of Saturated and Metastable Properties," *The Canadian Journal of Chemical Engineering*, 64(1), 1986 pp. 158–161. doi:10.1002/cjce.5450640123.

## Permanent Citation