微量镍的催化交流示波极谱法测定

Determination of Microamounts of Nickel by Catalytic AC-Oscillopolarography

本文报道了催化交流示波极谱测定微量镍的新方法。研究了Ni（Ⅱ）催化的［Fe（CN）6］3－－TI（Ⅰ）氧化还原反应体系，确立了催化体系测定微量镍的工作条件。线性范围为0．50～10．0mg／L；检测限为0．012mg／L，回收率为98．7％～99．6％，相对标准偏差为0．64％。有色溶液和沉淀不干扰测定，优于催化光度法。扩展了交流示波极谱的应用范围。用本法测定了合金和钢中镍的含量，结果满意。

A new catalytic AC-oscillopolarographic method for the determination of microamounts of nickel was proposed. Ni(Ⅱ) can catalyze potassium ferricyanide-thallium redox reaction in NaOH solution. The optimum condition accelerating the rate of catalytic reaction was established. A linear range is obtained from 0. 50 to 10.0 mg/L, the minimum detectable concentration of Ni (Ⅱ) is 12 μg/L, the recovery is 98. 7%～99. 6% and relative standard deviation is 0. 31 %. The determination is not affected by solution colour and precipitation formed. This method is better than the catalytic spectrophotometric method; hence the application field of AC-oscillopolarographic titration method may be extended. This method is satisfactorily applied to the determination of nickel in alloy and steel.