Determination Of Ru,Pt,Rh In Geological Samples By Oscillolarography After Separation And Enrichment By CPA-Ⅲ Forming Resin

A new chelate-forming resin bearing CPA-Шwas prepared by stirring a solution of CPA-Шwith a macroporous strong basic anion exchange resin D290. the adsorption property, various condition on the separation and perconcentration of noble metal and the evaluation of this method were studied. And determination of aurum, ruthenium, palladium, platinum and rhodium by Oscillopolarography was established. the evaluation of this method were studied.Various parameters such as pH, height of column, flow rate of sample solution, eluent type, volume and flow rate of eluent were investigated. When the pH (HCl) is 1.00, column is longer than 11.0 cm, the flow rate of sample solution is lower than or equal to 1.0 mL/min and elution rate with 0.1 mol/L HCl-3% thiourea(45mL) is lower than or equal to 0.6 mL/min, Ru, Pt ,Rh can be quantitatively preconcentrated. Their recoveries determined by Oscillopolarography are in the range of 94.0%～106.0%. It was proved that this forming resin with CPA-Шas ion exchange group is stable, and it can be used repeatedly. After adding a definite quantity of masking agent, a great number of the common metals are not adsorbed by forming resin.The optimal supporting electrolyte of testing by Oscillopolarography were investigated. Pt was surface hydrogen catalytic wave,It was found that Ru formed an electroactive complex with 2.5 mol·L-1 HCl-0.01% RB produced a catalytic wave with a peak at -1050 mV (vs sce), and Pt, Rh with 0.75 mol/L H2SO4—1.25×10-3 mol/L (CH2)6N4—1.2% NH4Cl—0.003% N2H4?H2SO4 produced the catalytic wave with the peak at -1035 mV (vs sce), -1230 mV (vs sce).Several factors were found that affect the experiment, and discussed the mechanism of the catalytic wave. Pt was surface hydrogen catalytic wave,Rh was catalytic hydrogen wave of adsorption, Ru was polarographic adsorptive catalytic hydrogen wave.The main advantages of this method are its simplicity and high speed. This method is proved to be practical and efficient by practice.