Analysis and extension of the Furter equation, and its application in the simulation of saline extractive distillation columns

Abstract

-Simulation of saline extractive distillation columns is a difficult task owing to the high nonlinearity of the rigorous models that represent these systems. The use of simple models to obtain initial estimates of equilibrium compositions may improve the stability and rate of convergence. One of the simplest models to study the vapor-liquid equilibrium of binary liquid mixtures + salt systems is the Furter equation. This model was analyzed in the present work by means of the incorporation of activity coefficient models in the ratio of relative volatility. This approach allowed systematic extensions of the Furter equation and a brief review of the theoretical basis of the original equation. As a result of these extensions, two simple equations were proposed and tested with experimental data from 20 systems, including binary liquid mixtures + salt systems and binary liquid mixtures + ionic liquid systems. Finally, one of these proposed equations was incorporated into the GKTM software in order to assess the utility of these simple models in the simulation of saline extractive distillation columns. The obtained results showed a significant improvement over the previous algorithm.

Data Determination and Process of Vapor–Liquid Equilibrium of Butane–Butene System by Complex Extractive Distillation Using Salt

“…The success of complex extractive distillation depends on selecting a suitable complex extractant. The extractant should take advantage of the reversible chemical reaction between metal ions and unsaturated hydrocarbons, such as olefin, to significantly improve the relative volatility of complex and saturated hydrocarbons and achieve separation from saturated hydrocarbons. − The principle of extractive distillation for butane–butene separation is based on the different electron cloud fluidity of butane and butene. Butane molecules do not have flowing electron clouds, whereas butene molecules have a pair of flowable electron clouds, so their attractiveness is different when a polar solvent is added.…”