钼(Ⅵ)-8-羟基喹啉-5-磺酸-亚硝酸根催化吸附波的研究及应用

Catalytic adsorptive wave of molybdenum(Ⅵ)-8-hydroxy-5-sulfonic-quinoline detering Mo in water

在5.0×10-3mol/L的盐酸介质中,钼与8-羟基喹啉-5-磺酸生成的络合物在NaNO2存在下,于-0.30V(vs,SCE)出现一尖锐、灵敏的极谱波.钼含量在0.2～400ng/mL范围内与波高呈线性关系,检测限为0.1ng/mL.用多种电化学方法研究了极谱波的性质及电极反应机理,证明络合波为吸附波.峰电流由中心离子Mo( )还原产生,Mo( )与络合剂的组成比为1∶1.方法用于自来水中痕量钼的测定,快速、灵敏、准确,结果满意.

<Abstrcat> Adsorptive catalytic polargraphic wave of the complex of molybdenum(Ⅵ)-8-hydroxy-5-sulfonic-quinoline complex is studied. Its peak potential is-0.30 V(vs,SCE). The optimum conditions are 5.0×10^(-3) mol/L HCl and NaNO_2, the detection limit and linear range of molybdenum(Ⅵ) are 0.1 ng/mL and 0.2~400 ng/mL respectively. Several electron chemical methods are used to prove that a polargraphic wave is a complex adsorptive one. The molar ration of molybdenum(Ⅵ) to 8-hydroxy-5-sulfonic in the complex is found to be 1∶1. The effect of more 8-hydroxy-5-sulfonic in the complex is found to be 1∶1. The effect of molar ration than 14 ions are tested. the proposed method is satisfactorily applied to the determination of trace amounts of molybdenum(Ⅵ) in water.