基于三电极体系计时电流法的氯离子检测

Chlorine ion detection based on chronoamperometry in three-electrode system

采用三电极体系工作原理,提出运用计时电流法测量氯离子浓度的方法,设计了一套基于三电极体系计时电流法的氯离子在线检测系统,通过采集计时电流法中电流的变化,实现对溶液中氯离子浓度的定量检测,根据推导能斯特方程,得到测量不同温度下溶液浓度与温度的公式,同时用标准浓度的氯化钠溶液对测量结果进行标定。实验结果表明,该系统具有稳定性好、精确度高、温度补偿能减小系统的测量偏差等优点。相比于两电极体系,三电极体系能够准确的测得工作电极的电位变化,运用计时电流法能有效提高系统的检测灵敏度,使该检测系统在工业水中氯离子的检测中具有很好的发展前景。

In this paper, based on the working principle of the three-electrode system, a method for measuring the concentration of chloride ion by chronoamperometry is proposed. An on-line detection system based on three-electrode system is designed , the quantitative detection of chloride ion concentration in the solution was achieved by collecting the change of current in chronoamperometry, according to the Nernst-equation, the temperature compensation formula for measuring the concentration of solution at different temperatures is obtained, and the measured results are calibrated with the standard Sodium Chloride Solution. The experimental results show that the system has the advantages of good stability, high precision and temperature compensation. Compared to the two electrode system, three-electrode system can accurately measure potential changes of the working electrode, using chronoamperometry can effectively improve the detection sensitivity of the system, so that the detection system has good prospects in the detection of chloride ions in industrial water.