邻苯二酚紫-CPB分光光度法测定铜合金中的锡

Pyrocatechol Violet-CPB Spectrophotometric Determination of Tin in Copper Alloy

研究了锡与邻苯二酚紫的显色反应,建立了测定铜合金中锡含量的分析方法。在盐酸介质中,在表面活性剂溴化十六烷基吡啶(CPB)的作用下,锡与邻苯二酚紫能形成一种蓝色的配合物,其最大吸收为波长664nm,表观摩尔吸光系数为1.1×105L·mol-1·cm-1,锡的含量在2—20μg/25mL范围内符合比耳定律。该法快速准确,应用于铜合金中锡的测定,测定结果与标准值相符。

The coloring reaction between catechol purple and tin was studied,a determination method of tin in copper alloy by spectrophotometry was established.The results showed that in ascorbic acid solution,and in the presence of surfactant cetyl pyridinium bromide（CPB）,the tin could forms blue complex with catechol purple,the complex has maximum absorption at 644nm,its apparent molar absorptivity is 1.1×105L·mol-1·cm-1.Beers＇s law is obeyed in the range of 2—20μg in the solution of 25 mL for tin.The method is simple and high sensitivity,The method is aeeurate and quiek,The method can be applied to the determination of tin in copper alloy,and the determination results are agreement with the standard values.