顺序注射-氢化物发生原子荧光光谱法测定铜精矿中砷

Determination of arsenic content in copper concentrate by hydride generation atomic fluorescence spectrometry with sequential injection system

利用盐酸、硝酸和液溴分解铜精矿样品，采用顺序注射-氢化物发生原子荧光光谱法检测样品中砷含量。讨论了样品中的主元素铜和其他元素对砷的干扰及消除方法；确定了适宜的硼氢化钾浓度。提出利用仪器的顺序注射装置的稀释功能测定含砷量较高的样品，扩展了测量的范围，提高了工作效率。砷质量浓度在0．90～100μg／L范围内与荧光强度呈良好的线性关系，方法检出限为0．30μg／L。该方法用于测定铜精矿中的砷，回收率可达89．1％～109．1%，相对标准偏差小于6．0%；铜精矿的测定结果与国家标准方法比较，结果吻合。

Copper concentrate sample was dissolved in HCl-HNO3-Br2 solution,and then the determination of arsenic was performed by hydride generation atomic fluorescence spectrometry with sequential injection system. A convenient method for the determination of arsenic content in copper concentrate is studied. The interference from the main element and other elements in copper concentrate and its elimination were discussed. The proper concentration of KBH4 was selected. The determination range was expanded by the dilution function of sequential injection system for high content arsenic and the efficiency was improved. The linear range was 0. 90--100 μg/L for arsenic. The detection limit was 0.30μg/L. The method has been applied to the determination of arsenic in copper concentrate with relative standard deviation of less than 6 % and recovery of 89.1%- 109.1%. The analytical results agree well with those obtained by the national standard method.