镍(Ⅱ)与3-噻唑偶氮-5-氨基苯酚体系络合吸附波的研究

Investigation of Adsorptive Wave of Nickel(Ⅱ)-3-Thiazolyazo-5-amino Phenol Complex

0．4mol／L（CH2）6N4-HCl（pH=5＋8）支持电解质中，Ni^2＋-3-噻唑偶氮-5-氨基苯酚体系络合物于-0．44V（vs．SCE）产生一灵敏的络合吸附波。该波的二阶导数峰峰电流与0．05—5．00mg／L范围内的Ni^2＋呈线性关系（r=0．9992，n=10）。检出限为0．02mg／L。本方法回收率在95％～106％之间。经多种电化学方法征明该波为络合物吸附波，其电极过程为不可逆过程，电子转移数为2。此外还试验了多种离子对峰电流Ip^n的影响。所拟方法已用于铝合金中镍的测定。

In （ CH2 ） 6 N4 - HCl （ pH = 5.8）, nickel （11） - 3-thiazolyazo-5-amino phenol complex causes a sensitive polarographic wave at the potential of -440 mV（vs. SCE）. The 2nd-order derivative peak current is linear with nickel（Ⅱ） concentration in the range of 0. 05 -5.00 mg/L（r =0.999 2, n = 10） with a detection limit of 0. 02 mg/L. The recovery is between 95% - 106%. Several electrochemical methods were used to study the properties of the wave. It is proved to be an adsorptive wave of the nickel complex, which electrode process is an irreversible reduced one with an electron transfer number of 2. The interference of diverse ions on the peak current was investigated. The proposed method has been applied to determine trace nickel in aluminium alloy with a satisfactory result.