催化光度法测定痕量硒  

A New Catalytic Method for Spectrophotometric Determination of Traces of Selenium

作　　者：姚凤姬[1] 董天祥 慈云祥[1] 

机构地区：[1]北京大学化学系

出　　处：《北京大学学报（自然科学版）》1990年第6期659-662,共4页Acta Scientiarum Naturalium Universitatis Pekinensis

摘　　要：本文通过研究Se(Ⅳ)催化氧化笨肼,进而与间苯二胺偶合生成黄色偶氮染料的最佳条件,建立测定Se的光度分析法。该染料的最大吸收波长为450nm,在此波长下的吸光度值与Se量有线性关系。表观摩尔吸光系数为3.0×10~6l·mol^(-1)·cm^(-1)。符合比尔定律的范围是0.4～32ppb,用于测定面粉及合成样中Se的回收实验均得到满意的结果。A new sensitive catalytic method for spectrophotometric determining traces 6f selenium(Ⅳ) is proposed. Selenium catalyzes the oxidation of phenylhydrazine by potassium chlorate to diazobenzene, which then is converted to a yellow azo dye by coupling with m-phenylenediamine. Their absorption maxima are 450nm. Optimum conditions for determining selenium have been established. The sensitivity presented as apparent molar absorptivity equals to 3.0×106. Beer's law is obeyed in the concentration range of 0.4ppb-32ppb. The method is sensitive and simple. By means of this catalytic reaction, submicrogram amounts of selenium can be easily determined. The mechanism of activation is investigated.

关 键 词：硒 催化光度法 催化分析 测定 

分 类 号：O613.52[理学—无机化学]