Application of ion-exchange fibers towards the chromatographic separation of valuable metals of Ni, Co, Ce, La and Nd from spent nickel-metal hydride batteries

The recovery of different valuable metals from waste nickel-metal hydride batteries has significant environmental and economic benefits for the sustainable use of resources. The five valent metals Ni, Co, Ce, La, and Nd in the waste NiMH mixed solution were separated using a chromatographic separation approach with ion-exchange fibers as the adsorbent material. By calculating the adsorption selectivity coefficients Kd, the adsorption selectivity of the ion exchange fibers for the five metals was in the order of Nd3+ >La3+ >Ce3+ >Co2+ >Ni2+. Experiments showed remarkable separation of the five valuable metals from the spent nickel-metal hydride batteries at a pH of 2, with the feed solution diluted to 1/10 of its original concentration, a full column length, a feeding flow rate of 3 mL/min, and an elution acid concentration of 2 mol/L. The adsorbent material also exhibited good recycling performance.