库仑滴定法测量微量砷

Determining Micro Amount of Arsenic with Coulomb Titration

为了减小微量砷测定中的误差，介绍了用库仑滴定法测量微量砷的一种方法。用双铂电极控制指示终点。结果表明，在实验ｐＨ范围内，无干扰离子的影响。最小检测下限０．６６μｇ·ｇ－１，相对标准偏差在１０‰以下，测量时间在１０ｍｉｎ以内，其操作简便、准确度高。

To reduce the determining error of micro amount of arsenic, a method testing micro amount of arsenic with coulomb titration method was introduced. Double platinum electrodes were used to control directing terminal. The results show that interference ion don′t exist at the range of pH. The minimum testing lower limit of arsenic was 0.66 μg·g -1 , the relative standard bias is under 10‰, the determining time is within 10 minutes. The method is characterized by simple operation and higher accuracy.