| The properties of platinum-group metals are similar. They always exist in the deposittogether. The separation and purification of the metals are difficult. On the basis of consultingthe internal and external references, the technology of ion exchange resin is used to extractand separate the platinum-group metals in the spent catalysts.Mainly adopt the operation of roasting, adsorption, elution of resin, sediment ofammonium chloride and reduction of hydrate hydrazine. The platinum and palladium in highdegree of purity are received. Recovery of platinum-group metals from waste catalysts by wetleaching method is inspected. After investigating various effects on the leaching ofplatinum-group metals, the optimum leaching conditions are determined. The extraction rateof platinum can reach90.5%and palladium96.0%from the mixed solution of6mol/LHCl-30%H2O2-0.02g/L NaF and stirring6hours under100℃. The volume ratio ofsolid-liquid in the spent catalysts is1:5.The elution craft of the iron and palladium in the anion exchange resin are studied.Through consulting the references, the hydrochloric （pH=1.1） and ammonia （25%） areregarded as the best eluting agent. Studies on the relationship of the elution rate with theelution time, the temperature and the consumption of eluting agent are carried out using theX-ray fluorescence. And the optimum elution conditions are fixed. The elution rate of iron canreach88.6%and palladium90.6%under the conditions of the elution time of120min, normaltemperature, and volumetric ratio of eluting agent to resin of5:1. The elution rate constant （k）is3.33×10-4s-1and the apparent activation energy is2.91kJ/（mol·K）. The elution rate of Pdcan reach90.6%. The result is in accordance with the result determined by GB/T. Thetechnology of XRF has a good feasibility for chemical element and veracity for quantitativedata in quantitative analysis. |
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