锌电解液中痕量铜、镉、镍和钴的快速同时测定

Rapid and simultaneous determination of trace amounts of copper,cadmium,nickel and cobalt in zine electrolytes

研究了丁二酮肟 氨 氯化铵 柠檬酸钠 明胶 抗坏血酸体系中Cu(Ⅱ )、Cd(Ⅱ )、Ni(Ⅱ )和Co(Ⅱ )的络合物吸附波 ,建立了同时、快速测定锌电解溶液中这些痕量元素的新方法。Cu(Ⅱ )、Cd(Ⅱ )、Ni(Ⅱ )和Co(Ⅱ )分别在 - 0 44V、- 0 76V、- 1 0 7V和 - 1 2 4V左右产生灵敏的络合物吸附波。信噪比为 3时 ,其检测限分别为 1 0× 1 0 - 8mol/L、1 3× 1 0 - 8mol/L、2 9× 1 0 - 1 0 mol/L和 3 6×1 0 - 1 1 mol/L。铜、镉、镍和钴的浓度分别为 2 0× 1 0 - 8mol/L～ 2 0× 1 0 - 5 mol/L、3 0× 1 0 - 8mol/L～ 3 0× 1 0 - 5mol/L、5 4× 1 0 - 1 0 mol/L～ 5 4× 1 0 - 7mol/L和 6 8× 1 0 - 1 1 mol/L～ 6 8× 1 0 - 8mol/L时 ,与相应峰电流之间有良好的线性关系。方法已用于锌电解液中铜、镉、镍和钴的快速同时测定 ,相对标准偏差分别小于或等于 4 7%、5 1 %、4 9%和 5 3 %。

Complex absorption polarographic waves of Cu(Ⅱ) ,Cd(Ⅱ),Ni(Ⅱ) and Co(Ⅱ) in the solution (pH=9.0) of diacetyldioxime-ammonia-ammonium chloride-soldium citrate-gelatin-ascorbic acid were studied and a new method for determination of trace amounts of Cu,Cd,Ni and Co in aqueous solutions was developed. The results showed that there were sensitive complex adsorption polarographic waves of Cu(Ⅱ),Cd(Ⅱ),Ni(Ⅱ) and Co(Ⅱ) complexes at about -0.44V ,-0.76V, -1.07V and -1.24V,respectively. The detection limits of copper, cadmium, nickel and cobalt were 1.0×10 -8 mol/L, 1.3×10 -8 mol/L,2.9×10 -10 mol/L and 3.6×10 -11 mol/L,respectively. Good linear relationships existed between the concentrations and the current peaks. The method was used in simultaneous determination of these metal ions in zinc electrolytes.