摘要
国标法检测COD时,不同浓度梯度的溴离子对COD测定影响不同。实验发现,国标法使用的硫酸汞对水样中溴离子不能起到屏蔽作用。溴离子的氧化贡献了表观的COD,使得检测值比真实值偏大。对COD浓度一定的水样,当溴离子浓度越大时,导致COD的检测偏差越大。而当溴离子浓度一定时,如果水样COD浓度越高,那么溴离子导致的检测偏差越小。
The influence of bromide ions with different concentration gradients on the determination of COD was investigated.It was found that mercury sulfate used in GB method for COD detection cannot shield the bromine ions in samples.The oxidation of bromide ions contributed to the apparent COD,making the detected value larger than the real value.For water samples with a certain COD concentration,the larger the bromide ion concentration,the greater the deviation of COD detection.When the concentration of bromide ion was constant,if the COD concentration of water sample was higher,the detection deviation caused by bromide ion will be smaller.
作者
卢阳
唐伟杰
刘君君
LU Yang;TANG Wei-jie;LIU Jun-jun(Jiangsu Nanjing University Huaxing Science and Technology of Environmental Protection Company,Jiangsu Yancheng 224000,China)
出处
《广州化工》
CAS
2019年第24期122-124,共3页
GuangZhou Chemical Industry
关键词
COD测定
溴离子
化学需氧量
干扰
COD determination
bromine ion
chemical oxygen demand
interference
