On the Applicability of Duolite GT-73 to Column Preconcentration of Gold and Palladium Prior to Determination by Inductively Coupled Plasma Atomic Emission Spectrometry

Abstract

The preconcentration of Au and Pd on Duolite GT-73 chelating resin with the thiol functional group was investigated prior to determination of these noble metals by means of inductively coupled plasma atomic emission spectrometry. It was found that AuIII and PdII were retained on the resin along with other concomitant metals (Al, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb and Zn) from different HCl-containing media. A two-step elution procedure was developed for the release of the noble metals. First 4.0 mol L−1 HNO3 solution was used to elute the base metals. The recovery of Au and Pd was performed afterwards using 0.50 mol L−1 solution of (NH2)2CS. Retrieval of Au and Pd retained on Duolite GT-73 was also carried out by decomposition of the resin in the open vessel system using H2SO4 with H2O2. The detection limits of Au and Pd evaluated for the devised protocol, with a preconcentration factor of 50, were 0.085 µg L−1 and 0.28 µg L−1, respectively. The proposed method was applied to the determination of Au and Pd in spiked electrolytic bath samples.