Adsorptive voltammetric study of thorium-alizarin complexon complex at a carbon paste electrode

作者：Li, JN^*; Yi, FY; Jiang, ZM; Fei, JJ

来源：Microchimica Acta, 2003, 143(4): 287-292.

DOI：10.1007/s00604-003-0070-9

• adsorptivevoltammetry
• thorium
• alizarin complexon
• carbon paste electrode

A new sensitive adsorptive voltammetric procedure is described for trace measurement of thorium. It is based on the cathodic stripping peak of the thorium-alizarin complexon (ALC) complex at a carbon paste electrode (CPE). The complex of Th(IV) with alizarin is adsorbed at a CPE in a mixed buffer solution (pH 5.0) which consists of 0.1 mol.L-1 sodium acetate and 0.04 mol.L-1 potassium biphthalate, yielding a sensitive cathodic voltammetric peak corresponding to the reduction of alizarin in the complex at -0.57 V (vs. SCE). The second-order derivative peak current of the complex is linearly dependent upon the concentration of Th(IV) over the range of 3.0x10(-9) similar to8.0x10(-7) mol.L-1. The detection limit is 1.0x10(-9) mol.L-1 for 180 s accumulation. The molar ratio of each component in the complex was estimated as n(Th(IV)):n(ALC)=1:1 by a continuous variation method. The electrode processes of the Th(IV)-alizarin complex at a CPE were investigated. The procedure was successfully applied to the trace determination of thorium in ore and clay samples.

• 出版日期2003-12
• 单位湘潭大学; 浙江师范大学