EXTRACTIVE DISTILLATION WITH AQUEOUS-SOLUTIONS OF HYDROTROPES

The effect of hydrotropes on vapor-liquid equilibrium of a mixture provides a potential technique of extractive distillation for systems which are difficult or impossible to separate by normal rectification. Various hydrotropes, such as sodium toluate, sodium toluence sulfonate, sodium cymene sulfonate, sodium mesitylene sulfonate and sodium salicylate, in aqueous solutions have been tested for the separation of close-boiling point mixtures, such as p-cresoI/2,6-xylenol, isopropanol/ tert-butanol, and sec-butanol/rerf-butanol. The changes in the relative volatility increase with the concentration of hvdrotrooe and with the hvdrotrope to solute ratio. © 1992, Taylor & Francis Group, LLC. All rights reserved.