江汉大学学报（自然科学版）

化学需氧量(COD)是我国各类废水监测中的必测指标之一.Fenton法是一种非常有效的废水处理方法.用重铬酸钾法测定Fenton体系中的COD时,残余的H2O2对测定结果存在干扰.分析了H2O2对COD测定产生干扰的机理,探讨了体系中H2O2对COD测定的干扰及消除方法.结果表明,H2O2对COD测定存在正干扰,随着H2O2浓度的增加,COD呈线性增大.采用Na2SO3可有效消除H2O2对COD测定的干扰,当体系的pH4时,对COD=500mg/L、H2O2=300mg/L的标准水样测定的相对误差为0.34%,相对标准偏差为1.12%.

Chemical Oxygen Demand(COD) is an indicator must to be measured in wastewater monitoring.Fenton process is an effective method in wastewater treatment.COD could be disturbed by the remainder of hydrogen peroxide using potassium dichromate method. This paper studies the interference mechanism of H2O2 for COD determinations,and discusses removal method of H2O2 interference in COD determinations.The experiment indicates that COD increases linearly with H2O2 increasing.Na2SO3 can remove the interference of H2O2 effectively.When pH 4, COD = 500 mg/L,[H2O2]= 300 mg/L, the relative error is 0.34% and the relatively standard deviation is 1.12%.