摘要
纳氏试剂比色法测定污水中氨氮,其蒸馏预处理过程存在耗时长、馏出液接收不便和操作繁琐等问题。文章对预处理及测定方法进行了优化,提出将水样蒸馏体积减少为50 m L,后期比色体积减少为25 m L,并去除硼酸吸收液,改为直接接收馏出液。经验证,其结果与国标方法无显著性差异,标样验证相对误差为-0.8%~0.9%,实际样品测定结果的相对标准偏差为0.9%~4.4%,加标回收率为94%~107%。优化的方法测量数据稳定,结果准确,在测定污水中氨氮具有实际应用意义。
In detection of NH3 - N in sewage by using Nash reagent colorimetric, there are several disadvantages, such as long time cost in pretreatment, distillate unsuitable for receiving and complex operation. This article presents an improved method for the pretreatment and determination, which is to reduce the volume of distillation to 50 mL and the volume of colorimetrie to 25 mL, in addition, receive the distillate directly in lieu of using boric acid. As is proved in the experiment, there were no significant differences between the empirical method and national standard method. The relative error was from - 0. 8% to 0. 9% on the standard sample tests. The relative standard deviations of determination results of actual samples were 0. 9% -4. 4% , and the recoveries was over the range of 94% - 107%. Experimental results showed that this optimization method has stable data and accurate results, which is of great practical significance to detect NH3 - N in sewage.
出处
《环境科学与管理》
CAS
2017年第5期123-125,共3页
Environmental Science and Management
关键词
氨氮
污水
蒸馏
纳式试剂法
NH3 - N
sewage
distillation
Nash reagent colorimetric
