石墨炉原子吸收光谱法测定地球化学样品中微量铬

邢夏; 徐进力; 何晓辉; 孙晓玲; 张芳

石墨炉原子吸收光谱法测定地球化学样品中微量铬

1.
中国地质科学院地球物理地球化学勘查研究所, 河北廊坊 065000
2.
中国地质科学院地球物理地球化学勘查研究所, 河北廊坊 065000
3.
中国地质科学院地球物理地球化学勘查研究所, 河北廊坊 065000
4.
中国地质科学院地球物理地球化学勘查研究所, 河北廊坊 065000
5.
中国地质科学院地球物理地球化学勘查研究所, 河北廊坊 065000

基金项目:

国土资源地质大调查项目资助(1212010511218-6-3)

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出版历程
- 收稿日期: 2010-06-05
- 修回日期: 2010-10-14

Determination of Trace Chromium in Geochemical Samples by Graphite Furnace Atomic Absorption Spectrometry

1.
Institute of Geophysical & Geochemical Exploration, Chinese Academy of Geological Sciences, Langfang 065000, China
2.
Institute of Geophysical & Geochemical Exploration, Chinese Academy of Geological Sciences, Langfang 065000, China
3.
Institute of Geophysical & Geochemical Exploration, Chinese Academy of Geological Sciences, Langfang 065000, China
4.
Institute of Geophysical & Geochemical Exploration, Chinese Academy of Geological Sciences, Langfang 065000, China
5.
Institute of Geophysical & Geochemical Exploration, Chinese Academy of Geological Sciences, Langfang 065000, China

摘要

摘要: 应用ZEEnit 600型石墨炉原子吸收分光光度计测定地球化学样品中微量铬。在分解样品过程中,加入高氯酸,使Cr(Ⅱ)、Cr(Ⅲ)同时被氧化为Cr(Ⅵ),避免了Cr(Ⅲ)和Cr(Ⅵ)的吸光度不同而造成的分析误差。采用最大功率升温和纵向加热石墨管技术,测定铬的原子化温度降低至2100℃,以抗坏血酸作基体改进剂,测定灵敏度得到提高,改善了方法精密度,并且延长了石墨管的使用寿命。采用交流塞曼扣背景测量技术,方法的线性范围为0~200 ng/mL,相关系数为0.9980;铬的检出限降低至0.05 μg/g(稀释因子为2500),方法精密度(RSD)为2.11%~5.96%。经国家一级地球化学标准物质验证,测定值与标准值吻合,结果准确可靠。
- 铬 /
- /
- 地球化学样品 /
- /
- 石墨炉原子吸收光谱法
Abstract: This article described the application of the ZEEnit 600 graphite furnace atomic absorption spectrophotometer on determination of trace chromium in geochemical samples. The HClO₄ was added during digestion to oxidize both Cr(Ⅱ) and Cr(Ⅲ) to Cr(Ⅳ), which avoid the analysis error caused by the different absorbencies of Cr(Ⅱ) and Cr(Ⅲ). The atomization temperature of Cr was reduced to 2100℃ by the technique of longitudinal heating at maximum speed in graphite furnace. The addition of ascorbic acid as matrix modifier improved the sensitivity and precision of the measurement, meanwhile increased the service life of graphite furnace. The linear range is from 0 to 200 ng/mL and the correlation coefficient is 0.9980 with background correction by using inverse Zeeman effect. The detection limits of the method is 0.05 μg/g (dilution factor is 2500), the precision of the method (RSD) is 2.11%-5.96%. The method has been validated by the national standard materials. The measured results were consistent with the certified values, and the results were accurate and reliable.
- chromium /
- geochemical /
- samples /
- graphite /
- furnace