PREPARATION, CHARACTERIZATION AND PERFORMANCE OF SILICA GEL-IMMOBILIZED POLY[N-CHLORANIL N,N,N',N'-TETRAMETHYLETHYLENEDIAMMONIUM DI-SULFOSALICYLATE] FOR CHROMATOGRAPHIC-SEPARATION OF HEAVY-METALS

Chelating resin loaded with 5-sulfosalicylic acid, Poly[N-chloranil N, N,N',N'-tetramethylethylenediammonium di-sulfosalicylate], was obtaine d by an ion-exchange reaction with N,N,N',N'-tetramethylethylenediamin e-chloranil copolymer as matrix. A useful chromatographic packing is p repared by immobilizing this chelating resin on silica gel. A detail a nalytical characterization of this silica-immobilized sorbent was carr ied out and optimum and selective sorption conditions for some heavy m etals under static and dynamic conditions were established. The maximu m absorption capacity was found to be 3.95 mu mol of metal ions per gr am of the sorbent at their respective optimum pH (optimum pH values fo r selective metal ions are: Cd2+, 3.2; Cu2+, 4.5; Fe3+, 5.0; Co2+, 6.9 ). The typical flow rates of 5 ml/min for Cu2+, Co2+ and Fe3+, and 3 m l/min for Cd2+ were found suitable for selective and quantitative sepa rations of these metals from the multicomponent mixtures of heavy meta ls present in the water samples. After separation of traces of metals on the sorbent and subsequent desorption with 1 M nitric acid, the met al ions were determined in the eluent by employing differential pulse anodic stripping voltammetry.