4-甲氧基-2,6-二(3,5-二甲基吡唑)-1,3,5-三嗪碳糊修饰电极测定Co(Ⅱ)的研究

Determination of Co(Ⅱ) at 4-methoxy-2,6-bis(3,5-dimetyylpyrazoyl)-1,3,5-triazine modified carbon paste electrode

用 4 甲氧基 2 ,6 二 (3,5 二甲基吡唑 ) 1 ,3,5 三嗪作碳糊修饰剂 ,采用示差脉冲阳离子溶出伏安法对痕量钴的测定进行了研究。测试介质为 1 .0mol LNH4Cl(pH 5 .50 )溶液 ,参比电极为Ag AgCl。向正电位方向扫描时 ,Co(Ⅱ )的氧化峰在 - 0 .0 7V ,Co(Ⅱ )的浓度在 1 .0×1 0 -7～ 1 .0× 1 0 -8mol L,2 .0× 1 0 -7～ 6 .0× 1 0 -6mol L两个范围内与峰电流成线性关系 ,且大多数阳离子不干扰测试结果。用于饮用水中Co(Ⅱ )的测定 。

A differential pulse anodic stripping voltammetry was developed for the determination of Co(Ⅱ) at 4-methoxy-2,6-bis(3,5-dimethylpyrazoyl)-1,3,5-triazine modified carbon paste electrode in 1.0 mol/L NH_4Cl solution (pH 5.50). The oxidation peak of Co(Ⅱ) was observed at -0.07 V(vs. Ag/AgCl) by scanning the potential in a positive direction. The current had a linear relationship with concentration of the Co(Ⅱ) in a range of 2.0×10^(-7)～6.0×10^(-6) mol/L for 0.5 min accumulation and in the range of 1.0×10^(-7)～1.0×10^(-8) mol/L for 1 min accumulation. Most of metal ions did not interfere with the determination. The method was applied to Co(Ⅱ) determination in water samples, and the results were satisfactory.