Separation of toxic Pb2+ metal from aqueous solution using strongly acidic cation-exchange resin: analytical applications for the removal of metal ions from pharmaceutical formulation

A strongly acidic cation-exchange resin Amberlite IR-120 was successfully used for the separation of toxic metal ions. The distribution coefficient values for various metal ions were performed in different acidic mediums using Amberlite IR-120 resin columns. On the basis of distribution coefficient values, Amberlite IR-120 was found to be selective for Pb2+ ion. A number of important quantitative binary separations of metal ions viz. Cd2+– Pb2+, Hg2+– Pb2+, Cu2+– Pb2+, Zn2+– Pb2+, Cd2+– Al3+, and Mg2+– Al3+ were achieved on the columns of this resin. In order to demonstrate the practical utility of these separations, Mg2+ and Al3+ were determined in commercially available pharmaceutical preparation namely digene using Amberlite IR-120 resin columns. The regeneration studies were carried out which demonstrated a decrease in the recovery of Pb2+ from 88 to 74% after five consecutive cycles.