Separation of Styrene- Ethyl Benzene Mixture Through Hydrotropy

Abstract

The field of separation using hydrotropy has been studied. Solvent extraction and ex- tractive distillation with aqueous solutions of hydrotropes are the novel separation techniques suitable for separation of close boiling mixtures. The present work is concerned with the separa- tion of styrene-ethyl benzene mixture using hydrotropic solutions of urea, nicotinamide and so- dium benzoate. The influence of a wide range of hydrotrope concentrations (0 to 3.0 mol/L) and different system temperatures (303 to 333 K) on the separation of styrene and ethyl benzene mixture was studied. The percentage extraction of styrene from the styrene-ethyl benzene mix- ture increases with an increase in hydrotrope concentration and also with system temperature. A Minimum Hydrotrope Concentration (MHC) was found essential to initiate significant extraction of styrene from the styrene-ethyl benzene mixture. The maximum enhancement factor, which is the ratio of the value in the presence and absence of a hydrotrope was determined. The Set- schenow constant, Ks, a measure of the effectiveness of a hydrotrope, was determined for each case.