以还原褪色反应催化光度法测定痕量钒

Catalytic Spectrophotometry for the Determination of Trace Vanadium Based on the Reducing Decoloration Reaction

本文在氯化钠存在下的柠檬酸－柠檬酸钾缓冲溶液中，以钒（Ⅴ）催化次磷酸钠还原罗丹明B褪色为指示反应，建立了痕量钒的动力学光度分析新方法。在90℃水浴中恒温反应10min，测定钒的线性范围为0～4．0μg／L，回归方程为△A＝0．1863CV＋0．0037，r＝0．9995。该法灵敏度高、选择性好，直接应用于水样和合金钢样中钒的测定，取得了满意的结果。

A catalytic spectrophotometry for the determination of trace vanadium was developed. It is based on an indicator reaction-rhodamine B being reduced by sodium hypophosphite on heating in citric acid buffer solution and in the presence of sodium cloride with the result of decoloration. The catalytic reaction is pseud-zero-order in reactants. The equation of regression of calibration graph is △A=0. 1863 Cv+0. 0037 (r=0.9995), and the range is 0~4.0μg/L for vanadium(Ⅴ). This method has been applied to the determinatiot of vanadium in water and alloy steel with satisfactory results.