气相分子吸收光谱法测定土壤和沉积物中亚硝酸盐氮、氨氮和硝酸盐氮  

Determination of Nitrite-Nitrogen,Ammonia-Nitrogen and Nitrate-Nitrogen in Soil and Sediment by Gas-Phase Molecular Absorption Spectrometry

作　　者：李爱民 吴昊 李桦欣 贺小敏 LI Aimin;WU Hao;LI Huaxin;HE Xiaomin(Hubei Provincial Eco-Environmental Monitoring Center Station,Wuhan 430072,China)

机构地区：[1]湖北省生态环境监测中心站,武汉430072

出　　处：《理化检验（化学分册）》2021年第9期794-798,共5页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：环保公益性行业科研专项基金(201509031)。

摘　　要：建立了气相分子吸收光谱法测定土壤和沉积物中亚硝酸盐氮、氨氮和硝酸盐氮含量的方法。参考HJ 634-2012中的提取方法,在(20±2)℃条件下,用氯化钾溶液作为浸提液浸提土壤和沉积物样品中的3种氮形态,离心后,采用气相分子吸收光谱法测定上清液中亚硝酸盐氮、氨氮和硝酸盐氮的含量。结果显示,亚硝酸盐氮、氨氮和硝酸盐氮的质量浓度在0.05~2.00 mg·L^(-1)内与其对应的吸光度呈线性关系,检出限(3.143s)分别为0.02,0.08,0.02 mg·kg^(-1),低于HJ 634-2012的。加标回收率分别为81.1%~96.2%,81.9%~88.1%和86.0%~105%,测定值的相对标准偏差(n=6)均在15%以内,准确度和精密度结果与HJ 634-2012的相当。方法和HJ 634-2012进行方法比对,2种方法的精密度和回收试验结果基本一致,且双侧F检验和t检验结果显示,这两种方法无显著性差异。A method for the determination of nitrite-nitrogen, ammonia-nitrogen and nitrate-nitrogen in soil and sediment by gas-phase molecular absorption spectrometry was established. Based on the extraction method in HJ 634-2012, 3 nitrogent forms were extracted from soil and sediment samples with potassium chloride solution at(20±2)℃. After centrifugation, the contents of nitrite-nitrogen, ammonia-nitrogen and nitrate-nitrogen in the supernatant were determined by gas-phase molecular absorption spectrometry. The results showed that linear relationships between mass concentrations of nitrite-nitrogen, ammonia-nitrogen and nitrate-nitrogen and their absorbances were kept in the same range of 0.05-2.00 mg·L^(-1), and detection limits(3.143s) were 0.02, 0.08, 0.02 mg·kg^(-1), respectively, lower than those given by HJ 634-2012. Recoveries from the spiked recovery test were in the range of 81.1%-96.2%, 81.9%-88.1% and 86.0%-105%, respectively, with RSDs(n=6) of the determined values within 15%. Tests for method comparison between the proposed method and HJ 634-2012 were made, results of tests for recovery and precision of the 2 methods were basically the same, and there was no significant difference between the 2 methods by results of two-sideds F test and t test.

关 键 词：气相分子吸收光谱法 亚硝酸盐氮 氨氮 硝酸盐氮 土壤 沉积物 

分 类 号：O657.32[理学—分析化学]