Column separation of divalent metals from sulfate solutions using impregnated resins containing di(2-ethylhexyl)phosphoric acid

Column separation of divalent zinc and copper ions from binary aqueous sulfate solutions using di(2-ethylhexyl)phosphoric acid (D2EHPA)-impregnated macroporous resins was systematically studied at 298 K. The breakthrough curves for binary metal sorption were measured as a function of resin type, feed flow rate, feed metal concentration ratio and aqueous pH, and D2EHPA concentration in the resin phase. It was shown that an overshoot behavior in the breakthrough curve for copper, the metal having a lower affinity with the impregnated resins, was observed near the breakpoint for other metal, zinc. The dependence of the degree of separation of zinc to copper on experimental parameters was quantitatively discussed.