Ion-exchange resins containing S-bonded dithizone and dehydrodithizone as functional groups : Part 1. Preparation of the Resins and Investigation of the Sorption of Noble Metals and Base Metals

The one-step reaction of dehydrodithizone with chloromethylated polystyrene yields the anion-exchanger P-TD. Reduction of the immobilized tetrazolium groups of P-TD produces a chelating resin, P-D, containing S-bonded dithizone as the functional group. Distribution coefficients as a function of acidity are presented for 27 metal ions, to establish the selectivity of these sorbents for noble metals. For gold and platinum group metals, the ion-exchangers show marked differences in loading capacities, rates of simultaneous sorption in static conditions and efficiencies in column tests. The P-TD anion exchanger seems to be more profitable than the P-D chelating resin for most purposes.