摘要
本文介绍用碘离子选择电极催化电势动力学法对测定钒(Ⅴ)进行的研究,发现去氢抗坏血酸是钒(Ⅴ)催化BrO_3-氧化I^-体系的一种良好的活化剂,详细地研究了各种因素对测定的影响,找出了测定钒(Ⅴ)的较佳条件。该法测定钒(Ⅴ)浓度的线性范围很宽,检测限为2×10^(-10)mol/l,灵敏度比文献报道的高3个数量级。对几种离子的干扰进行了试验,柠檬酸可以有效地掩蔽这些离子的干扰。此法曾应用于测定自来水和头发中的钒,得到了较好的结果。
Iodide ion-selective electrode was used to study the determination of V(V) in catalysis po-tentiometric kinetic method. It was discovered that dehydroascorbic acid is a very effective acti-vator in the system of BrO_3^- as oxidant. Various factors that affected the determination of V(V)was studied. The optimum condition of determination of V(V) was found out. The detectionlimit of V(V) is 2×10^(-10) mol/l. The linear rang is very wide and the sensitivity of this methodis 3 order higher than references reported. The interferences of some ions were examined. Citricacid can cover the interferences of these ions. Analysis of vanadium in natural water and humanhair and standard recovery experments have been done. The variation coefficients were 3.6% (n=8)and 5. 9% (n=4).
关键词
碘
离子选择电极
催化动力学
钒
Catalysis kinetic method
iodide ions-elective electrode
vanadium
catalysis potentiometry
