Removal of Ni(Ⅱ) and Co(Ⅱ) ions from acidic solutions by Lewatit TP-260 resin

摘要

This paper examines Ni(II) and Co(II) adsorption from an aqueous sulfate solution onto Lewatit TP-260 ion exchange resin, and the later desorption of these ions. The influence on metals adsorption of contact time, the pH of the metal-containing solution, the initial concentration of metals in the solution, and the amount of resin was examined in batch experiments. The coefficients of adsorption under different experimental conditions were then determined. Batch experiments were also performed to examine desorption or elution at different volumes/resin ratios and HCl (eluant) concentrations. Adsorption experiments were also performed in minicolumns to study the performance of the resin under conditions of continuous use. Different flow rates for the inlet metals-bearing solution and different resin weights were tested in the adsorption phase (performed at pH 3.1). The results of the batch experiments showed that the resin is able of adsorbing both metals under a range of conditions. The mechanism that best described this adsorption varied depending on the metal and experimental conditions used. The results of the continuous experiments showed that the nickel and cobalt adsorption is increased with increasing the resin weight and decreasing the flow rate of the metals-bearing solution.