MECHANISM OF MERCURY PERMEATION THROUGH LIQUID MEMBRANE CONTAINING DICYCLOHEXYL-24-CROWN-8

Abstract

The permeation mechanism of mercury was studied, using a newly devised three-liquid phase contact apparatus with flat interfaces. It is possible by using the apparatus for a feed, membrane and stripping solutions to contact in a similar manner as in the liquid membrane technique. Mercury in the feed phase permeates through the membrane phase of xylene solution of dicyclohexyl-24-crown-8 (C-24) to the stripping phase of sodium chloride solution. The permeation rate of mercury can be explained by a permeation model which takes account of the dissolution of mercury to the membrane phase and the interfacial reaction between mercury and C-24, in addition to the diffusion processes in the aqueous film and the membrane phase.