SILICA GEL-BONDED CATIONIC POLYELECTROLYTE WITH FERRON AS COUNTERION - APPLICATION TO PRECONCENTRATION OR ELIMINATION OF TRACE-METALS

An integral N-based cationic polymer, poly[N-xylylene N,N'-dicyclohexy lethylenediammonium dibromide], was immobilixed through hydrogen bondi ng on the surface of silica gel. The chelating ligand, 7-iodo-8-hydrox yquinolino 5-sulfonic acid (Ferron), was subsequently attached to the matrix by ion-exchange method; this renders an extremely stable statio nary phase, free from leaching complications, under electrostatic (sal t) bond interactions. Analytical characteristics of this sorbent were studied. The optimum sorption conditions for CU2+, Cd2+, Zn2+, Pb2+, C o2+, Ni2+, and Fe3+ under static and dynamic (column) methods were asc ertained. The chelator was found to be selective for the retention of CU2+, Pb2+, and Fe3+ from multi-element mixtures. The relatively fast kinetics of the sorbent with the time required to reach half of the ma ximum sorption (t(1/2) value 2 min) and the percentage attainment of e quilibrium in 2 min (P-2 min value > 50%) for most of the heavy metals , excluding Ni2+, reveal the suitability of the chelating resin in col umn operation, especially in single column ion-chromatography, The spe cific applications of the sorbent in purification of supporting electr olyte/buffers required for voltammetric detection are also explored.