摘要
湖泊底泥中生物可利用态铬是对湖泊生态环境最有影响的铬赋存形态,分别用弱有机酸或螯合缓冲剂对底泥中生物可利用态铬进行萃取分离。在流动注射系统中,分别以串联在流路中阴、阳离子交换微型柱分离,NH4NO3＋抗坏血酸和H2SO4两种洗脱液同时逆向洗脱,实现了对底泥可利用态铬中Cr（Ⅵ）和Cr（Ⅲ）同时在线分离和原子吸收光谱法测定。交换时间2min,洗脱50s,Cr（Ⅵ）和Cr（Ⅲ）回收率分别为85.4%-94.8%和96.7%-106%。本方法对实际样品中不同价态铬进行测定,铬回收率可达95%。Cr（Ⅵ）和Cr（Ⅲ）的检出限和最大相对标准偏差分别为0.9μg/L、6.4%和2.7μg/L、3.5%。
A rapid and sensitive method for separation and determination of Cr（Ⅵ） and Cr（Ⅲ） in bottom mud of lake by flow injection on-line preconcentrtion system and GFAAS was developed. The available Cr（Ⅵ） and Cr（Ⅲ） were extracted by HOAc or EDTA ＋ NH4 NO3 and adsorbed simultaneously by an anion and a cation resin microclummn and then eluted simultaneously by 2 mol/L NH4 NO3 ＋ 0.05 mol/L ascorbate and 2 mol/L H2SO4, respectively. The elution was performed for 50 s after adsorption for 2 rain, and the efficiencies of elution were 85.4% -94.8% and 96.7% - 106% for Cr（Ⅵ） and Cr（Ⅲ） respectively. The detection limits of the method were 0.9 μg/L and 2.7 μg/L with relative standard deviations of 3.5% and 6.4% for the determination of Cr（Ⅵ） and Cr（Ⅲ） in sample, respectively.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2007年第3期451-454,共4页
Chinese Journal of Analytical Chemistry
基金
国家重点基础研究发展规划基金资助项目(No.2002CB412304)
关键词
流动注射
原子吸收光谱法
形态分析
铬
底泥
Flow injection, atomic absorption spectroscopy, speciation analysis, chromium, bottom mud
