| A new type of alizarin red-S chelating resin was synthesized by chelating alizarin red-S (1,2-dihydroxyanthraquinone-3-sulfonic acid sodium) with macroporous strong basic anion resin D296-R. The chelating resin can dissociate -OH into H+ in acidic medium and turn into -O-, which can coordinate with large precious metal iodine complex anion [MeI4]2- to form a stable chelate. Au, Pt and Pd in samples can effectively be separated from base metals in a wide acidity range, and the effect of NO3- on the adsorption of precious metals can be inhibited. Combined with a high-pressure closed dissolved ore method, the recovery rates of Au, Pt and Pd were more than 92%, and the detection limits were 0.047, 0.082 and 0.051 ng/g for Au, Pt and Pd, respectively. It is applied to the determination of Au, Pt and Pd in the primary reference materials for the geochemical composition analysis of platinum group elements, the relative error (RE) between the results and the identified values was -7.58%~10.9%, and the relative standard deviation (RSD) was less than 9.86%. |
