微波消解镉柱还原光度法测定水中总氮  

Detection of Total Nitrogen in Water with Microwave Digestion Cadmium Column and Spectrophotometry

作　　者：魏福祥[1] 马晓珍[1] 雷立改[1] 张帆[1] 王浩然[1] 

机构地区：[1]河北科技大学环境科学与工程学院,河北石家庄050018

出　　处：《分析科学学报》2011年第5期615-618,共4页Journal of Analytical Science

基　　金：国家863课题(No.2007AA09210109)

摘　　要：以碱性过硫酸钾为消解液,利用微波快速消解水样,流动注射与镉还原柱相连,分光光度法测定水样中的总氮。在消解升温时间200s,消解温度125℃,消解时间750s,还原泵速20r/min,镉柱装填高度10cm,pH=8.0～9.0的测定条件下,氮的检出限为0.005mg/L,线性范围为0～5mg/L,相对标准偏差小于3%。对河水、景观用水、水库水、海水进行测定,加标回收率为97%～106%。Total nitrogen in water is determined by microwave digestion,flow injection and cadmium column reduction spectrophotometry using basic potassium persulphate as digestion solution.The optimal conditions were as follows：temperature-rise time is 200 s,water sample is heated to 125℃,digestion time is 750 s,the pump speed of reduction is 20 r/min,the length of the cadmium column is 10 cm,and pH is 8.0 to 9.0.The linearity range is 0～5 mg/L,the detection limit is 0.005 mg/L,and the relative standard deviation is 3%.The proposed method is applied to the determination of total nitrogen in water samples fetched from river,landscape and recreation area,reservoir and sea with recoveries ranging from 97% to 106%.

关 键 词：微波消解 流动注射 镉柱 总氮 分光光度法 

分 类 号：O657.32[理学—分析化学]