电位溶出装置的组装及其性能测试

Assembly and Property Test of the Potential Stripping Apparatus

利用电解仪、电位计和记录仪等组装的电位溶出装置,用于教学实验,可直观地诠释电位溶出分析法的基本原理。用该装置,Cd^(2+),In^(3+),Pb^(2+)三种离子可以同时测定,分辨能力良好。在0.5mol·L^(-1)硝酸钾底液中测定Cd^(2+)时,以旋转玻碳电极为工作电极,于-1.0V(vs·Ag/AgCl电极)预电解4min,静止溶出,Cd^(2+)浓度在5～65μg·L^(-1)内,线性回归方程y=0.375+0.85x,相关系数r=0.9997,相对标准偏差RSD=4.09％。

The potential stripping apparatus was assemblied by means of an electrolytic analyzer,a potentlometer and a recorder. The basic prlnciple of potential stripping method can be explained easily through teaching experiments by this apparatus. Three ions Cd2+,In3+and Pb2+ can be determined si-multanebusly in this apparatus. In the base solution of 0. 5 mol/L KNOs ,Cd2+ was determined by way of a step of preelectrolysis and accumulation at the potential -0.0 Volt (vs. Ag/AgCl) and a following step of static stripping with a working electrode of rotating glassy carbon. The linear regression eguation was y = 0. 375 + 0,85.x,with a correlation coefficient(r) 0. 999 7 and a relative standard derivation(RSD) 4. 09% within the experimental range.