Analysis of a new routine for evaluating VLE data using the Gibbs differential equation

Abstract

Many isobaric and isothermal VLE systems have been published and continue to be published. In general, these systems are thermodynamically verified using the area test and mostly the point–to–point test of Fredenslund et al. These data verification procedures are based on different developments of the Gibbs􀀀 Duhem equation. This article develops a new procedure for verifying and analyzing isothermal and isobaric systems. In addition, a new thermodynamic verification process is included that directly applies the Gibbs differential equation. The point–to–point evaluation of experimental data using the Gibbs differential equation and correlating the data with the NRTL activity coefficient model, without applying procedures to minimize deviation, allows us to determine data errors and reduce them in order to validate the analyzed system.