Prediction of effectiveness of solvent using distribution coefficient calculation in solvent extraction with the help of Hansen solubility parameters

ABSTRACT

Selection of solvent is the crucial factor in development of a successful solvent extraction process. The equilibrium data needed pertain to selectivity and distribution coefficients for each individual components present in the system. In continuation with earlier work, the results of an attempt to provide a theoretical basis for predicting a suitable solvent for extracting ethanol from its aqueous solution are presented in this work. The approach used is based on the 3-D Hansen Solubility Parameters. The results obtained are compared for prediction of better solvent for separation with maximum error obtained 9.37%.

KEYWORDS:

• Solvent selection
• water ethanol mixture
• solubility parameter
• predication of equilibrium data

Novelty Statement

Solvent extraction remains one of the fundamental separation techniques in the chemical industrial separation and recovery till today. In solvent extraction selection of solvent is most crucial activity that decides the separation efficiency. This requires lot of experimentation. Development of mathematical model for determination of the best solvent using theoretical methods will be considered in this proposed work. This may save lot of expenditure on experiments and analysis. Analysis methods generally are costly and difficult. This may lead to even development of formula or model of most appropriate solvent selection and the model may be used for development of simulation software. This may further be coupled with manufacturing of those solvents, which may solve very difficult problems of separation using extraction in the chemical industries.

The work presented here covers the application of mathematical modeling approach published in our earlier research to the ethanol water solvent extraction problem. The present work reviews research from the field of extraction of ethanol from its aqueous mixture published earlier. The problem of selection of solvent to recover hydrocarbons from its aqueous mixture is approached by generating a mathematical model based on the HSPs. Besides the common organic solvents; ionic liquids are also used. The model so developed defines the degree of separation by calculating the distribution coefficient and selectivity factor. In addition, the model can be used for developing new solvents with tailor-made properties. Hence the work describe in this paper is useful for easy and safe selection of solvent for liquid-liquid extraction-based separation with less consumption of time and cost.