Solid-phase extraction for the decontamination of alkali metal, alkaline earth metal, and ammonium salts from heavy metal ions

Salicylaldoxime-immobilized silica gel was characterized and used as a potential sorbent for heavy metal ions, viz. Cu(II), Ni(II), Co(II), and Zn(II). The experimental conditions were optimized both in batch and column processes to achieve the maximum efficiency. Kinetic and thermodynamic parameters as well as isotherm constants were evaluated to test the feasibility of the process. The role of various metal ions and different anions were tested in order to monitor the process in case of real samples. The alkali metal, alkaline earth metal, and ammonium salts do not have any effect on the said process. This differential behavior can be effectively used for the decontamination of alkali metal, alkaline earth metal, and ammonium salts from Cu(II), Ni(II), Co(II), and Zn(II) ions via solid phase extraction following AAS measurement. The purification of the salts was confirmed by voltammetric experiment. (C) 2002 Elsevier Science (USA).