酚二磺酸分光光度法测定硝态氮影响因素研究  

Study on the Influencing Factors of Nitrate-spectrophotometric Method with Phenol Disulfonic Acid

作　　者：李颖 

机构地区：[1]荆州市江陵县环境保护局,湖北荆州434100

出　　处：《广东化工》2015年第7期176-178,共3页Guangdong Chemical Industry

摘　　要：硝酸盐氮是水质监测的重要指标之一,酚二磺酸分光光度法则是目前最为常用的测定硝态氮含量的方法。而该方法对反应条件要求严格,易受干扰。文章总结了测定过程中可能出现的影响因素,就文中所提影响因素进行了研究。实验结果表明：工作曲线与标准曲线接近,但工作曲线耗时长且线性关系较差,故建议使用标准曲线;p H与氨水加入量均能影响硝态氮的测定,实验确定最适p H为8~9;氨水最佳加入量应为3 m L（至溶液颜色不变）;氯离子和硝酸根离子均干扰实验,应去除这两个离子后再测定。本研究为减小各因素的影响、提高硝态氮测定结果的准确度提供了基础数据和理论依据。Nitrate nitrogen is one of the important indexes of water quality monitoring, which is determined generally by nitrate-spectrophotometric method with phenol disulfonic acid. But this method is strict in reaction conditions and susceptible to interference. Several influencing factors were summarized and studied in this paper. The results demonstrated that the working curve was approximate to the standard curve, but which was time-consuming and poor linear relationship, so the standard curve was suggested for use. The determination of nitrate nitrogen was influenced by pH and the addition of ammonia. The optimum pH was 8-9 and the addition of ammonia was 3 mL （the solution remained the same color）. The chloridion and nitrite ion were removed before the determination, which could interference the experiment. The study provided the basic data and theoretical basis of reducing the influence of various factors and improving the accuracy of nitrate determination results.

关 键 词：硝态氮 酚二磺酸法 校准曲线 影响因素 

分 类 号：O65[理学—分析化学]