|关键词: 总氮 泥沙 干扰 过滤
|A Method of Improving the Accuracy in the Determination of Total Nitrogen in Surface Water Containing Sediments
JI Yi，YAN Jin，SUN Juan，QIU Zhanchen
Nanjing Environmental Monitoring Center，Nanjing，Jiangsu 210013，China
|In determination of total nitrogen in surface water containing sediments using the alkaline potassium persulfate digestion UV spectrophotometry，data accuracy is often influenced by insoluble floc.In this study，the digested sample was filtered through a 0.45μm aqueous needle filter，which quickly and efficiently removed the insoluble floc and improved the accuracy of total nitrogen determination.Experimental results showed that using this method，the RSD was below 2.0% and the recoveries were in the range of 92.0 %~96.5 %，which met the laboratory quality control requirements.
|Key words: Total nitrogen Sediments Interfering Filtering