Dn RT dln f[4

A practical expression for vapour-liquid equilibrium consideration thus takes the form:

where the subscripts V and L indicate fugacity in the vapour phase and liquid phase, respectively. Correlation and prediction of vapour-liquid equilibria must satisfy the equal fugacity condition. The main concern is to relate these fugacities to T, P, and the compositions of the liquid and vapour phases.

Design of distillation operations requires reliable experimental vapour-liquid equilibrium values for conditions corresponding to the desired operation. Available data may frequently be either fragmentary or for conditions different from the desired operating conditions. On many occasions, the needed experimental values are not available at all. In order to make suitable interpolation and extrapolation of the available data, and to make acceptable estimates of unavailable data, it is necessary to take advantage of the limited data available and apply prediction methods developed on the basis of reasonable assumptions. In this article, discussion is limited to correlation and prediction of the vapour-liquid equilibrium values for organic and nonelectrolyte mixtures at conditions such that Raoult's law cannot be used to represent the behaviour of all components over the complete concentration range. The emphasis is placed on the equilibrium T-P-x-y.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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