原子荧光光谱法测定化探样品中的砷和锑

摘要

对氢化物原子荧光光谱法测定化探样品中砷和锑元素的分析条件,尤其是浸提法及预还原顺序进行了考察.样品经王水和王水溶液(1+1)分别浸提后以不同顺序预还原,结果表明,王水的氧化性会降低硫脲-抗坏血酸的还原效果,预还原时降低王水浓度能提高测定结果的准确度.在优化的测定条件下,样品中砷、锑测定结果的相对标准偏差分别为0.6％,2.7％；回收率分别为95％～101％,91％～106％；检出限分别为0.020,0.026 ng／mL.改善样品处理方法后测定结果的的准确度得到提高.%The conditions of sample preparation and detection for As and Sb in geochemical samples by AFS especially the extraction method and the order of pre-reduction were investigated.Samples were extracted by aqua regia and aqua regia solution (1+1),then pre-reductant agent was added in different orders,the results showed that the reduction effect of thiourea-ascorbic acid was reduced by the oxidizability of aqua regia,and the accuracy of the determination results might be improved by reducing the concentration of aqua regia before pre-reduction.Under the optimized conditions,the relative standard deviations of As and Sb were 0.6％ and 2.7％,the recoveries were 95％-101％ and 91％-106％,the detection limits were 0.020 and 0.026 ng/mL,respectively.