ZrC-桑色素络合物在碳糊电极上的二次导数吸附伏安法测定Zr的研究

Determination of Zirconium by Second-order Derivative Adsorption Voltammetry of Zirconium C-Morin Complex at a Carbon Paste Electrode

研究了Zr 桑色素络合物在碳糊电极正电位区的吸附伏安行为 ,并利用其在 0 .74V处的二次导数吸附氧化峰电流与Zr(Ⅳ )浓度为 6 .0× 10 -9～ 2 .0× 10 -6mol/L呈线性而测定Zr;检出限为 3.0× 10 -9mol/L(S/N =3)。最佳测定条件为 :2 .0mol/LHCl、1.0× 10 -5mol/L桑色素 ;富集电位为 0V(vs .SCE) ;扫描速度为2 5 0mV/s。该法不需萃取分离 ,可直接用于岩石样品中Zr的测定 。

A new method was presented for the determination of zirconium based on adsorptive oxidation of the zirconium-morin complex in the positive potential range of a carbon paste electrode (CPE). Optimal analytical conditions were found to be: 2.0 mol/L HCl, 1.0×10 -5 mol/L morin, a 0 V(vs. SCE) accumulation potential and a 250 mV/s scan rate. The concentration of Zr was directly proportional to the second-order derivative peak height at about 0 74 V . The linear range was 6.0×10 -9 ～2.0×10 -6 mol/L. The detection limit for Zr was as low as 3.0×10 -9 mol/L (S/N=3) for 180 s accumulation. The proposed method was applied successfully to the determination of zirconium in ore samples without separation.