微波辅助提取-氢化物发生原子荧光光谱法测定土壤中无机砷

Hydride Generation-Atomic Fluorescence Spectrometric Determination of Inorganic Arsenicin in Soil Samples with Microwave-assisted Extraction

建立了微波辅助提取-氢化物发生原子荧光光谱法测定土壤中无机砷的分析方法。用正交试验设计结合单因素试验优化了样品粒度、提取温度、提取时间、固液比等微波提取条件，研究了共存离子对无机砷测定的干扰情况。方法的线性范围为0．25～40．0μg/g，无机砷的检出限为0．05μg/g，样品加标回收率为92．9％～105．0％。方法的精密度（RSD，n=11）为0．3％。与水浴提取法相比，微波辅助提取法具有快速、高效的优势。方法已用于分析3个不同产地有代表性土壤中无机砷含量。

A method has been established for the determination of inorganic arsenic in soils by hydride generationatomic fluorescence spectrometry combined with microwave-assisted extraction. The microwave-assisted extraction operating conditions were optimized by the orthogonal test design combined with the mono-factor test. The interference from coexisting ions on inorganic arsenic determination was eliminated using aseorbie aeid-thiourea-eitfie acid. The linear range of the calibration curve for inorganic arsenic is 0.25 -40μg/g. The detection limit is 0.05 μg/g for inorganic arsenic. The recovery of inorganic arsenic in soil samples was 92. 9% - 105.0% with precision of 0.3% RSD （n = 11 ）. Compared with the results obtained from the water bath extraction method, the microwave-assisted extraction method was time-saving and more efficient. The method has been successfully applied to the extraction and deterruination of inorganic arsenic in soil samples from different regions.