催化动力学光度法测定微量钛

Kinetic spectrophotometric method for the determination of micro titanium

KBrO3在硫酸介质中可氧化固绿使其褪色，Ti（Ⅳ）对反应有催化作用，由此建立了一个简单的、灵敏度高的测定微量钛的新体系。考察了酸度、反应物浓度、反应时间、温度和其它离子对反应的影响，并确定了反应的最佳条件。在一定范围内，固绿吸光度降低值与钛的浓度有定量关系。方法的线性范围为0．04～1．2μg／mL Ti（Ⅳ），检出限为0．009μg／mL。将该方法用于铝合金标准样品中微量钛的测定，结果与认定值一致。

Based on the catalytic effect of trace titanium（Ⅳ） on the oxidation of solid green by potassium bromate in the sulphuric acid medium, a new sensitive kinetic spectrophotometric method for the determination of trace titanium was developed. The influence of acidity, concentration of reactants, reaction time, reaction temperature and foreign ions were discussed and the optimum reaction conditions were also established. The decrease in the absorbance of solid green had a quantitative relationship with the concentration of titanium（Ⅳ） within a certain range. The proposed method allowed the determination of titanium（Ⅳ） in the range of 0.04--1.2 μg/mL with good precision and accuracy, and the detection limit was 0. 009μg/mL. The method has been applied to the determination of trace titanium in aluminum alloy certified reference materials, the results were in agreement with certified values.