离子色谱-衍生-分光光度法同时测定水中三价铬和六价铬  

Simultaneous Determination of Trivalent Chromium and Hexavalent Chromium in Water Using Ion Chromatography-Derivation-Spectrophotometry

作　　者：姚欢[1] 谢永洪[1] 钱蜀 赵云芝[1] 

机构地区：[1]四川省环境监测中心站,成都610041

出　　处：《四川环境》2012年第6期58-63,共6页Sichuan Environment

摘　　要：本文建立了离子色谱法同时测定水中三价铬和六价铬的方法。样品中的三价铬经柱前衍生后,泵入分析柱,与样品中的六价铬分离,分离后的样品经在线柱后衍生,流入可变波长检测器,分别在365 nm和540 nm检测。利用正交实验找出最佳分析条件:水浴加热2 min,加热温度80℃,柱后衍生液流速1.1 ml/min。方法在10 min内完成水中三价铬和六价铬分析,三价铬和六价铬线性范围分别为0.05～10 mg/L和0.005～1 mg/L,方法检出限低,分别为18.1μg/L和0.267μg/L,精密度分别为1.16%(0.4 mg/L Cr3+,n=7)和3.07%(0.08 mg/L Cr6+,n=7),样品分析时的加标回收率在96%～102%之间。A method for simultaneous determination of trivalent chromium and hexavalent chromium were established using the technology of ion chromatography-derivation-spectrophotometry. Through precolumn derivatization, the trivalent chromium was pumped into the analysis column and separated from hexavalent chromium in the sample. With on line post-column derivation, the separated sample flowed into the variable wavelength detector to be determined at 365 and 540nm. The optimal analysis conditions were found out by orthogonal experiments as follows： heating in water bath at 80 ~C for two minutes and the with liquid flow rate of 1. lml/min for post-column derivation. By the method, the analysis was fulfilled in 10 minutes. For trivalent chromium and hexavalent chromium, the results were as follows： linear ranges of 0. 05 - 10 and 0. 005 - 1 mg/L, the detection limits low as 18. μg/L and 0. 267μg/L, the accuracies of 1.16 % （0. 4 mg/L Cr3＋ , n =7） and 3.07% （0. 08 mg/L Cr6＋ , n =7） respectively. The samples spiking recoveries ranged in 96% - 102%.

关 键 词：离子色谱法 三价铬 六价铬 同时测定 

分 类 号：X832[环境科学与工程—环境工程]