样品经艾斯卡试剂(碳酸钠和氧化锌)半熔法分解,沸水提取,使硒与主量金属元素铜、铅、锌及其他过渡金属和贵金属元素得到分离;滞留在溶液中的干扰元素,通过在酸性介质中加铁盐来掩蔽.采用焙烧分离-氢化物发生-原子荧光光谱法测定铜矿石、铅矿石和锌矿石中的硒,干扰少、灵敏度高.确定了最佳条件为盐酸浓度30%,硼氢化钾浓度20 g/L,铁盐浓度1 ms/mL;干扰元素的允许量铜为40 mg/L,铅为8 mg/L,锌为400 mg/L.同时对铜、铅、锌主量金属元素进行分离效率试验,效果好.方法检出限为0.0203 μg/g,测定范围为0.15～100μg/g.经全国不同地区7家实验室采用铜矿石、铅矿石和锌矿石国家标准物质验证,精密度的重复性限和再现性良好,准确度高.建立的方法也适合于土壤及多金属矿物中硒的测定.%The sample was digested using the semi-melting method with Aiskaer reagents ( sodium carbonate and zinc oxide) and extracted by boiling water which separated Selenium from the main metal elements including Cu, Pb, Zn, other transition metals and precious metals. Meanwhile, other interference elements remaining in the solution are sheltered by adding molisite. A method for determining trace Selenium in copper ore, lead ore and zinc ore by hydride generation-atomic fluorescence spectrometry has the advantages of low interference and high sensitivity. The best measurement conditions are 30％ for hydrochloric solution, 20 g/L for KBH4, 1 mg/mL for molisite and permissible dosage of interference elements; Cu 40 mg/L, Pb 8 mg/L, Zn 400 mg/L. In addition, separation efficiency experiments were conducted for primary elements including Cu, Pb, and Zn. The detection limit of the method is 0.0203 μg/g for Se and measuring range of the method is 0.15～100 μg/g. This method was used to conduct experiments in seven labs from different areas using national standard materials with a precision repeatability limit, good reproducibility limit and high accuracy. The method discussed in this paper can be applied to determine trace Se in soil and multimetallic minerals.
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