Original Uses of the Liquid Nature of the Stationary Phase in CCC. I. Extraction and Separation of Transition Metal Ions

Abstract

Displacement chromatography is a way of using the chromatographic technique, in which the solutes are separated in bands in the stationary phase. Because the stationary phase is a liquid in CCC, it possible to stop the displacement process when the separated bands are still in the stationary phase. The collection of the stationary phase bands is possible. This way of using a CCC instrument was described for the separation of transition metal ions. Co²⁺, Ni²⁺, Cu²⁺, and Zn²⁺ were separated using diethylhexyl phosphoric acid (DEHPA) and heptane as the stationary phase through a reversed micelle extraction process.

The extraction constants of the cations were determined accurately by CCC. The displacement process and collection of the stationary heptane phase allowed recovery of ion bands with purity higher than 95%. A ten-fold concentration of the cations in the organic phase can be obtained. The process is described.

The effect of the mobile phase pH and the ion concentrations are studied. This use of CCC allows both the deionization of charged aqueous phases and the separation and recoveq of the water-contained cations by concentrating them in the heptane phase.