氯化钯作基体改进剂石墨炉原子吸收光谱法测定土壤中的铍.pdf

2012年12月
矿测试
Vol 3
December 2012
ROCK AND MINERAL ANALYSIS
975-979
文章编号:0254-5357(2012)06-0975-05
氯化钯作基体改进剂石墨炉原子吸收光谱法测定土壤中的鈹
姚朝英,任兰
(南京市环境监测中心站,江苏南京210013
摘要:铍是一种对人体有害的金属元素,土壤中铍的测定目前尚无国家标准方法。本文采用盐酸一硝酸
氲氟酸体系徽波消解、石墨炉原子吸收光谮法测定土壤样品中的铍,实验了钯、硝酸铝、硝酸镁、钙盐的增敏
效果。结果表明,以氯化钯为基体改进剂,灰化温度和原子化温度分别提高到1100℃和2650℃,原子化峰
形尖锐,背景吸收很小,提高了测定灵敏度;其他三种基体政进剂虽然也能提高测定灵敏度,但背景吸收较
大。采用优化的实验条件,Fe、Mg、K、Na、Ca、Ti、Cu、Ba、Mn、Zn、Pb、Sr等共存元素对测定不产生千扰。铍的
浓度在0~4.00g/工.范围内线性良好,方法检出限为0.01g/g,精密度(RSD,n=6)为3.5%~6.7%,实际
土壤样品的加标回收率为84.0%~113.0%,土壤国家标准物质的测定值在标准值的误差范固内。本法与
萃取光度法、电感耦合等离子体发射光谱/质谱法相比,操作简便,分析成本较低。
关键词:土壤;皱;徽波消解;石墨炉原子吸收光谱法;氯化钯;基体改进剂
中图分类号:S151.93;0614.21;0657.31
文献标识码:B
Determination of Beryllium in Soils by Graphite Furnace Atomic
Absorption Spectrometry with Palladium Chloride as a Matrix Modifier
YAO Chao-ying, REN Lan
Environmental Monitoring Center of Nanjing, Nanjing 210013, China)
Abstract Beryllium is a harmful metal element and there is no national standard method for its determination in
soils. A method system was established for the determination of Beryllium in soils by Graphite Furnace Atomic
Absorption Spectrometry (GFAAS) with hydrochloric acid-nitric acid-hydrofluoric as microwave digestion. The
sensitizing effects of palladium, aluminum nitrate, magnesium nitrate and calcium salt were investigated. The
results showed that atomic shape was sharp, background absorption was small and sensitivity was improved with
palladium chloride as the matrix modifier when the ashing temperature and atomization temperature were increased
to 1 100C and 2650C, respectively. The other 3 modifiers improved sensitivity but background absorptions werc
larger. The conditions of experiment were optimized and the coexisting elements Fe, Mg, K, Na, Ca, Ti, Cu, Ba
Mn, Zn, Pb and Sr had no interference. The results showed that good linearity ranged from 0 w/L to 4.00 ug/L
detection limit was 0. 1 wg/g(sampling quality was 0.2000 g and constant volume was 50 ml), RSD of standard
samples were from 3. 5 to 6.7C, and spiked recoveries of the actual soil sample were from 84.0% to 113.0%
The result of national standard material was in the range of certified values. Compared with extraction
spectrophotometric method, Inductively Coupled Plasma-atomic Emission Spectrometry and Inductively Coupled
Plasma-mass Spectrometry, this method is simple and inexpensive.
Key words: soils; beryllium; microwave digestion; Graphite Furnace Atomic Absorption Spectrometry; palladium
hloride: matrix modifier
收稿日期:2012-03-23;接受日期:2012-07-28
基金项目:2009年度国家环境保护标准制修订基金资助项目(1067)
作者简介:姚朝英,高级工程师,主要从事环境监测工作。E-mail: yaocyoole@sina,com。
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