氯气校正法测定高氯废水中化学需氧量方法的改进

Improvement of the determination method of COD in high chlorine waste water

高氯废水中化学需氧量的测定通常采用氯气校正法,该方法消除了氯离子对CODcr.测定的影响,但在实践中发现这种方法对测定结果仍可产生正误差.如果采用含氯空白校正的方法进行测试,结果表明相对误差在0.1%～1.1%之间,加标回收率为102%～105%,可提高方法的准确度.

The method of chlorine compensated was adopted to determine COD in high chlorine waste water, it eliminated the determination influences by chlorine, but in practice the results bring positive error, in this paper the method of blank containing chlorine compensated was adopted, the results shows that the relatively error of standards ranged from 0.1% to 1.1%, the standard addition recovery rate is in the range of 102%～105%, improve the accuracy of method.