改进测定水中氨氮分子吸收光谱法的试验研究

Determination of Ammonia Nitrogen in Water by Improved Gas Phase Molecular Absorption Spectrometry

水中氨氮含量是反应水质状况的重要指标。文章对测定水中氨氮气相分子吸收光谱法(标准号HJ/T195-2005)进行了改进试验研究。第一,对氧化剂的配比进行了改进,使氨氮的测定范围扩展至100μg。第二,对标准HJ/T195-2005中直接使用亚硝酸钠标准溶液做标准曲线的处理方式也做了探讨。通过一系列对比实验认为,应用硫酸铵标准溶液做工作曲线更加准确合理。最后应用改进后的气相分子吸收光谱法和纳氏比色法或滴定法对多种实际废水样品进行同时测定。结果表明,改进后的气相分子吸收光谱法测定氨氮的范围更宽,灵敏度更高和准确度更好。

Ammonia nitrogen content in water is an important indicator of water quality. Gas phase molecular absorption spectrometry in national standard HH/T195-2005 was studied and improved. The constitutional ratio of oxidizing agent was improved which can oxidize the amoufit of ammonia nitrogen up to 1001xg. The standard curve which uses sodium nitrite as the standard solution in national standard method was also discussed. Through a series of experiment, it was found that it is more reasonable and precise to draw working curve which use ammonium sulfate as the standard solution. A few types of wastewater were determined by the improved method, whose measured results agree basically with those of the standard method. Results indicated that the improved gas phase molecular absorption spectrometry has a broader measuring range, a higher sensitivity and accuracy.