纳氏试剂分光光度法测定氨氮的质量控制  

The Quality Contol of Determination of Ammonia and Nitrogen by Nessler's Reagent Spectrophotometry Method

作　　者：邓鹂 顾晓燕 陈静 迟伟伟 苟德国 

机构地区：[1]大丰市环境监测站,江苏大丰224100

出　　处：《广州化工》2011年第19期84-87,100,共5页GuangZhou Chemical Industry

摘　　要：纳氏试剂分光光度法测定水质氨氮时受到多种因素的干扰,直接影响分析的质量。为解决这一系列问题,采取相应的质量控制措施,试验表明:纳氏试剂应冷藏;絮凝沉淀采取静置沉淀或离心,取上清液测定即可;玻璃器皿先用酸性洗剂浸泡洗涤;采室外平行样时先用玻棒搅拌;"比色前稀释"和"比色后稀释"相对误差和相对偏差均满足分析要求;水样进行蒸馏预处理时,馏出液体积在120 mL时即可;显色时间在10～30 min之间为宜;室温在20～25℃之间较好;水样经加酸酸化保存,在样品测定时先将pH调至中性。There were many factors interferred the determination of ammonia and nitrogen in water with Nessler＇s reagent spectrophotometry method,which directly affected the quality of the analysis.In order to solve the problems,corresponding quality control measures were adopted.Experiment showed that Nesster＇s reagent should be refrigerated,flocculating sedimentation should take quiet place precipitation or centrifugal,and take only supernatant aslo do.Glass vessels with acidic detergent for first washing,in outdoor parallel samples,stirred with a glass rod first,the relative error and deviation of dilution before colorimetric and dilution after colorimetric met the analysis requirement.Water samples can be preprocessed distillation,when liquid volume 120 mL,color time 10~30 min and in 20~25 ℃,the result was better.The water samples saved by acidification,and pH was neutral before determing.

关 键 词：纳氏试剂分光光度法 氨氮 质量控制 

分 类 号：X832.02[环境科学与工程—环境工程]