IMPREGNATED RESINS AS NOVEL SORBENTS FOR REMOVAL OF TOXIC METAL IONS FROM AQUEOUS SOLUTIONS

The adsorption/solid phase extraction (SPE) processes are the most attractive methods for effective removal of metals ions from different aqueous solutions. In SPE procedure, the choice of appropriate adsorbent is a critical factor to obtain full recovery and high enrichment factor. For this reason, modification and impregnation techniques of solid phase have been employed to increase the surface adsorption capacity, and to enhance the removal efficiency and selectivity of the solid phase. Novel types of resins incorporating macrocyclic ligands may be the best choice for the removal of toxic metal ions. The modification of Amberlite XAD-4 with macrocyclic ligands results in the high capacity and selectivity of the impregnated resins. The extractant is retained in the micropores of an inert polymer without any chemical bonds onto the polymer matrix and the properties of the impregnated extractant are responsible for the adsorption of novel resin. In this study the efficiency of impregnated resins as solid extractants using solid–liquid extraction and sorption characteristics of impregnated resins were evaluated. The removal efficiency of impregnated resin was determined under various conditions of treatment system. Impregnated resins as novel sorbents have been found efficient and easily regenerable and can be used several times.