差分脉冲吸附溶出伏安法同时测定锌电解液中铜(Ⅱ)、钴(Ⅱ)和镍(Ⅱ)

Simultaneous Determination of Copper(Ⅱ),Cobalt(Ⅱ) and Nickel(Ⅱ) in Zinc Electrolyte by Differential Pulse Adsorptive Stripping Voltammetry

在含有亚硫酸钠的pH 8.8的氨水-氯化铵缓冲溶液中,丁二酮肟-锌体系与铜(Ⅱ)、钴(Ⅱ)和镍(Ⅱ)产生络合物吸附波,据此提出了差分脉冲吸附溶出伏安法测定锌电解液中铜(Ⅱ)、钴(Ⅱ)和镍(Ⅱ)含量的方法。结果表明:铜(Ⅱ)、钴(Ⅱ)和镍(Ⅱ)的峰电位分别在-0.65V,-0.92V和-1.06V。铜(Ⅱ)、钴(Ⅱ)和镍(Ⅱ)的质量浓度分别在6.02×10-6～1.00×10-3,6.01×10-5～1.20×10-3,8.04×10-6～4.03×10-4g.L-1范围内与峰电流呈线性关系,检出限分别为9.41×10-7,1.14×10-5,5.48×10-6g.L-1。

In an NH3 （aq.） NH4Cl buffer solution of pH 8. 8 containing Na2SO3, adsorptive complex waves of dimethylglyoxime-zineon system with Cu（ Ⅱ ）, Co（ Ⅱ ） and Ni（ Ⅱ ） were observed. Based on this fact, a method of differential pulse adsorptive stripping vohammetry for the determination of Cu（ Ⅱ ）, Co（ Ⅱ ） and Ni（ Ⅱ ） in zinc plant electrolyte was proposed. It was found that the peak potential of Cu（ Ⅱ ）, Co（ Ⅱ ） and Ni（ Ⅱ ） complexes were obtained at --0. 65, --0. 92 and --1.06 V, respectively. Linear relationships between values of peak current and concentration were found in the range of 6. 02×10-5-1. 00×10-3g·L-1 for Cu（Ⅱ）, 6. 01×10-6-1. 20×10-2g·L-1 for Co（Ⅱ）, and 8. 04×10-6 -4.03×10-4 g·L-1 for Ni（ Ⅱ ）. Values of detection limits of Cu（ Ⅱ ）, Co（ Ⅱ ） and Ni（Ⅱ ） found were 9.41×10-7, 1.14×10-5 and 5.48×10-6g·L-1 respectively.