钒（V）－3，4－二羟基苯甲酸－溴酸钾体系极谱吸附催化波的研究

STUDIES ON THE POLAROGRAPHIC ADSORPTIVE CATALYTIC WAVE OF VANADIUM (V )- 3, 4 - DIHYDROXYBENZ OICACID - POTASSIUM BROMATE SYSTEM

在ＰＨ５．４的乙酸盐缓冲溶液中，钒（Ｖ）－３，４－二羟基苯甲酸一溴酸钾体系产生一灵敏的吸附平行催化极谱波，峰电位在一０．６３Ｖ（ＶＶ．ＳＣＥ），二次导数峰高与钒（Ｖ）浓度在２·０×１０－９～ｌ．２×１０－６ｍｏｌ／Ｌ范围内呈线性关系，检测限达１×１０－９ｍｏｌ／Ｌ．研究了电极过程机理，用本法测定了土壤、煤飞灰等样品中的钒，结果满意．

A sensitive polarographic adsorptive catalytic wave of vanadium (V )- 3, 4 - dihydroxybenzoic acid (DHBA) complex was obtained by single - sweep polarography in 0. 1 mol/L acetate buffer solution containing 5. O× 10-5 mol/L DHBA and 0. 05 mol/L potassium bromate at pH 5. 4. The peak potential appears at - 0. 63 V(vs. SCE). The change of peak height with the concentration of vanadium is linear in the range from 2. 0 × 10-9 to 1. 2 × 10-6 mol/L. The detection limit for vanadium is 1× 10-9 mol/L. The electrode processes of the adsorptive catalytic wave have been studied. The method has been applied to the determination of vanadium in coal fly ash and soil standard samples with satisfactory results.