ORIGINAL USES OF THE LIQUID NATURE OF THE STATIONARY-PHASE IN CCC - I- EXTRACTION AND SEPARATION OF TRANSITION-METAL IONS

Displacement chromatography is a way of using the chromatographic tech nique, in which the solutes are separated in bands in the stationary p hase. Because the stationary phase is a Liquid in CCC, it possible to stop the displacement process when the separated bands are Still in th e stationary phase. The collection of the stationary phase bands is po ssible. This way of using a CCC instrument was described for the separ ation of transition metal ions. Co2+, Ni2+, Cu2+, and Zn2+ were separa ted using diethylhexyl phosphoric acid (DEHPA) and heptane as the stat ionary phase through a reversed micelle extraction process. The extrac tion constants of the cations were determined accurately by CCC. The d isplacement process and collection of the stationary heptane phase all owed recovery of ion bands with purity higher than 95%. A ten-fold con centration of the cations in the organic phase can be obtained. The pr ocess is described. The effect of the mobile phase pH and the ion conc entrations are studied. This use of CCC allows both the deionization o f charged aqueous phases and the separation and recovery of the water- contained cations by concentrating them in the heptane phase.