Determination of limit of stability of chemical systems

Abstract

This work presents a new statement of the stability criteria for pure substances described by Peng-Robinson equation of state. A method for solving the limit of stability of chemical systems has been developed, based on the use of Newton – Raphson’s method of convergence for finding the roots of equation. The method provides a thermodynamically rigorous method for predicting the limit of stability of pure substances. This method can also be used for multi-component mixtures, provided that a different stability criterion is assumed. Application was made to Benzene. At 522K, the limit of stability of liquid and vapour Benzene were 10 bar and 35 bar respectively. Peng -Robinson equation of state was found to be adequate in predicting the limit of stability of both liquid and vapour phases of benzene.