Trace Determination of Scandium Using Adsorption Voltammetry of Mix-Polynuclear Complex of Scandium-Calcium-Alizarin Red S at Carbon Paste Electrode

摘要

A novel method was described for the determination of ultra trace amount of scandium based on the cathodic adsorptive voltammetry of the mix-polynuclear complex of scandium-calcium-alizarin red S at a carbon paste electrode （CPE）. The 2nd-order derivative linear scan voltammograms of the adsorbed complex were recorded by model JP-303 polarographic analyzer from 0.0 to -1.0 V （vs. SCE）. The experimental conditions of the working procedure were optimized. The results show that the complex can be adsorbed on the surface of the CPE, yielding one peak at -0.61 V, corresponding to the reduction of the alizarin red S in the mix-polynuclear complex at the electrode. The detection limit of Sc3+ is 1.0×10-10 mol·L-1 for 3 min of accumulation time. The procedure was successfully applied to the determination of trace amount of scandium in the sample ores.