铬(Ⅲ)-邻菲啰啉-亮黄缔合体系光度法测定痕量铬(Ⅲ)  

Spectrophotometric determination of trace Cr(Ⅲ) with Cr(Ⅲ)-phen-bright yellow complex system

作　　者：李人宇[1] 李咏梅[2] 吴俊杰[1] 

机构地区：[1]连云港师范高等专科学校,江苏连云港222006 [2]淮海工学院化学工程学院,江苏连云港222005

出　　处：《冶金分析》2011年第3期76-78,共3页Metallurgical Analysis

基　　金：连云港市科技项目(SH0816);江苏省海洋资源开发研究院科技开放基金项目(JSIMR09C08)

摘　　要：在pH 5.7 NaAc-HAc缓冲溶液中,铬（Ⅲ）与邻菲啰啉（phen）和亮黄（BY）反应生成稳定的离子缔合物[Cr（phen）]BY3,在最大吸收峰382 nm处体系吸光度明显增强,建立了分光光度法测定痕量铬（Ⅲ）的新方法。试验了酸度、试剂用量、表面活性剂、反应温度和时间的影响,确定了最佳反应条件。铬（Ⅲ）质量浓度在0-0.30μg/mL范围内符合比尔定律,表观摩尔吸光系数为1.31×105L.mol^-1.cm^-1,检出限为3.63μg/L。方法用于测定电镀废水中铬（Ⅲ）,相对标准偏差分别为1.9%和1.4%（n=5）,回收率分别为96%和99%。A new method for the determination of trace Cr（Ⅲ） by spectrophotometry was developed.The method was based on the fact that Cr（Ⅲ） could react with phen and bright yellow（BY）,forming a stable ion-association complex [Cr（phen）]BY3 in NaAc-HAc buffer solution at pH 5.7,which resulted in a obvious enhancement of absorbence at the maximum absorption peak of 382 nm.The effect of acidity,reagent dosage,surfactant,reaction temperature and reaction time was investigated to obtain the optimal conditions.The Beer＇s law was obeyed in the range of 0-0.30 μg/mL for Cr（Ⅲ）.The apparent molar absorption coefficient was 1.31×105 L·mol-1·cm-1 and the detection limit was 3.63 μg/L.The method has been applied to the determination of Cr（Ⅲ） in electroplating wastewater samples.The relative standard deviations（RSD,n=5） were 1.9 % and 1.4 %,respectively and the recoveries were 96 % and 99 %,respectively.

关 键 词：分光光度法 铬 邻菲啰啉 亮黄 离子缔合物 

分 类 号：O657.32[理学—分析化学]