硫离子选择性电极催化动力法测定微量硒

硒对苦味酸氧化硫离子的反应有催化作用，本文采用通用硫离子选择性电极检测硫离子浓度的变化速率，进行硒的催化动力学测定，硒的测定范围为０．１～２．０ｍｇ·Ｌ￣（－１），硒浓度在ｌｍｇ·Ｌ￣（－１）时测定的变异系数为２．７％，此法方便、快速，用于阳极泥中硒含量的测定，回收率为９４％～１０４％。

Catalytic Determination of Microamounts of Selenium With Sulfide-Selective Electrode

A method is described for the determination of selenium,bascd on its catalytic effecton the picrate-sulfide reaction,involved a variable-time kinetic procedure using potentiometric moni-toring with a sulfide-selective electrode. The determination is appropriate in 5 ×10￣(-3)mol·L￣(-1)picrate-4.5×10￣(-5)mol·L￣(-1)Na_2S-4.5 ×10￣(-5)mol·L￣(-1)Fe(Ⅲ)-0.0020mol·L￣(-1) EDTA-0.15mol·L￣(-1)Na_2CO_3-0.10mol·L￣(-1)NaHCO_3-2.5×10￣(-3)mol·L￣(-1) ascorbic acid,and pH=9.48～9.60, The dcter-mination is convenient and rapid at 25℃。The range of the method of selenium is in 0.1～2.0mg/L,thevariation coefficient is 2.7 % when the concentration of selenium is 1mg/L. The method has beensuccessfully applied to determination of selenium in anodic residue.