DPD分光光度法测定低浓度游离氯的方法优化

Optimization of DPD Spectrophotometric Method for Determining Low Concentration Free Chlorine

在采用国家标准《水质游离氯和总氯的测定N,N-二乙基-1,4-苯二胺分光光度法》(HJ 586-2010)测定游离氯时,发现低浓度标准曲线的相关系数难以达到标准中相关系数应>0.999的要求。文章针对可能会对实验结果的准确性产生影响的条件进行试验,对游离氯的测定条件进行优化。实验结果表明,在酸化时间20 min、显色时间10 min以内的条件下进行测定时,相关系数达到要求,可以满足日常监测的需求。

When the national standard Determination of Free and Total Chlorine in Water Quality N,N-Diethyl-1,4-Phenylenediamine Spectrophotometry(HJ 586-2010)was used to determine free chlorine,the correlation coefficient of the low concentration standard curve was found to be poor.It is difficult to meet the requirement that the correlation coefficient in the standard should be>0.999.Test the conditions that may affect the accuracy of the experimental results and optimize the measurement conditions of free chlorine.The experimental results show that when the standard song is measured under the conditions of acidification time 20 min and color development time within 10 min,the correlation coefficient meets the requirements and can meet the needs of daily monitoring.