微波消解-石墨炉原子吸收法测定土壤中铊

Determination of Thallium in Soil by Mixing Matrix Modifier-Platform Graphite Furnace Method with Microwave Digestion

通过研究土壤消解体系、混合基体改进剂的使用、石墨管类型的选择和标准加入定量过程对测定结果的影响,建立了适用于土壤中重金属铊的微波消解-平台石墨炉原子吸收方法。结果表明,使用HNO_3-HF-H_2O_2消解体系对土壤进行微波消解,石墨炉原子吸收测定过程采用Pd（NO_3）_2/Mg（NO_3）_2混合基体改进剂和平台石墨管,土壤中铊的检出限可达0.05 mg/kg,线性相关系数为0.996,加标回收率在95.0%~105.0%。使用该方法测得的结果与ICP-MS法比较,无统计学差异。改进后的方法具有简单快捷、灵敏度高、重现性好、线性范围广、结果准确等优势,易于推广使用。

A novel method for the determination of thallium in soil was developed by means of microwave digestion and platform graphite furnace atomic absorption spectrometry. The use of matrix modifiers and the graphite tube types to the improvement of thallium determination were explored. The results showed that more sensitive determination results were obtained by using HNO_3-HF-H_2O_2 digestion system and adding mixed matrix modifiers Pd（ NO_3）_2/ Mg（ NO_3）_2with platform graphite tube. The linear correlation coefficient was 0. 996,and the limit of detection was 0. 05 mg / kg. The recovery of the spiked soil samples were from 95. 0% to 105. 0%. The determination results are no significant difference compared with that obtained from expensive ICP-MS method. The developed method is simple,fast,sensitive,accurate,and suitable for the determination of thallium in soil.