Study on the Separation and Determination of Palladium, Platinum and Rhodium by Solid Phase Extraction and Ultra Performance Liquid Chromatography

Abstract

In this paper, a new method for the simultaneous determination of palladium, platinum and rhodium ions by solid phase extraction and ultra performance liquid chromatography was studied. The palladium, platinum and rhodium ions were pre-column derivatized with p-rhodanine azobenzoic acid (RBA) to form coloured chelates. The Pb-RBA, Pt-RBA and Rh-RBA chelates were enriched by solid phase extraction with C₁₈ cartridge. The separation of these chelates on ACQUITY UPLC BEH C₁₈ (1.7 μm 2.1 mm × 50 mm) column was satisfactory with 38 % acetonitrile (containing 0.05 mol L^-1 of phosphoric acid) as mobile phase. Palladium, platinum and rhodium were separated completely within 2.5 min. The detection limits (S/N = 3) of palladium, platinum and rhodium reaches 12, 18 and 20 ng L^-1, respectively. This method was applied to the determination of palladium, platinum and rhodium in water, urine and soil samples with satisfactory results.