二溴羧基偶氮胂分光光度法测定废水中铅  

Spectrophotometric determination of lead in wastewater with dibromocarboxyarsenazo

作　　者：朱启红[1] 夏红霞[1] 

机构地区：[1]重庆文理学院,重庆402168

出　　处：《冶金分析》2009年第7期78-80,共3页Metallurgical Analysis

基　　金：重庆文理学院科研启动经费课题资助

摘　　要：研究了二溴羧基偶氮胂（DBKAA）与Pb^2＋的显色反应，建立了微波消解-分光光度法测定废水中Pb^2＋的方法。实验结果表明，以硝酸、过氧化氢为消解剂，消解功率为480W、消解时间为3min时水样消解效果最佳；在PH10，室温25℃条件下，溶液中Pb^2＋与二溴羧基偶氮胂生成蓝紫色络合物，其最大吸收峰在590nm波长处，表观摩尔吸光系数为3．9×10^3L·mol^-1·cm^-1。25mL溶液中，吸光度值与Pb^2＋在0．11～15μg范围内呈线性关系，方法检出限为24．8μg／L。本法用于含铅废水中Pb^2＋的分析，加标回收率为99％～102％，相对标准偏差为1．3％～1．9％，测定结果与原子吸收光谱法测定结果无显著差异。The coloring reaction of dibromocarboxyarsenazo （DBKAA） with Pb^2＋ was studied. Accordingly, a spectrophotometric determination method of Pb^2＋ in wastewater was established with microwave digestion. The experiments showed that the digestion of water sample had best results under following conditions： nitric acid and hydrogen peroxide as digestion agent, digestion power of 480 W and digestion time of 3 min. At pH 10 and room temperature （25 ℃）, the Pb^2＋ in solution could form a blue purple complex with arsenazo. The maximal absorption peak of this complex was at 590 nm, and the apparent molar absorptivity was 3.9×10^3L·mol^-1·cm^-1. Beer＇s law was obeyed for Pb^2＋ in the range of 0.11--15 /μg/25 mL, with detection limit of 24.8 μg/L. This method was applied to the determination of Pb^2＋ in wastewater. The recoveries of standard addition were 99 %-- 102 %, and the relative standard deviations （RSD） were 1.3 %/6--1.9 %. There was no significant difference between the determination results of this method and those of atomic absorption spectrometry.

关 键 词：微波消解 分光光度法 二溴羧基偶氮胂(DBKAA) 铅 

分 类 号：O657.32[理学—分析化学]