微波消解-氢化物发生-原子荧光光谱法测定二氧化钛中痕量砷和锑

采用HNO3+HCl+HF作为消解试剂,样品经微波消解后,用L-半胱氨酸预还原,以氢化物发生-原子荧光光谱法对二氧化钛中砷和锑进行了分析。探讨了盐酸、硼氢化钾溶液浓度以及样品还原处理对测定结果的影响,确定了实验的最佳测定条件。结果表明,砷、锑在0~25μg/L范围内线性关系良好,线性相关系数均为0.9999,砷和锑的检出限分别为0.058μg/L和0.075μg/L。对5μg/L的砷、锑连续11次进样,测得结果的相对标准偏差分别为0.71%和0.78%。方法用于二氧化钛样品的测定,测定结果与ICP-AES测定结果相符,回收率为96%-108%。

Simultaneous determination of trace arsenic and antimony in titanium dioxide by microwave digestion-hydride generation-atomic fluorescence spectrometry

A determination method of trace arsenic and antimony in titanium dioxide by hydride generation-atomic fluorescence spectrometry(HG-AFS)was established.In this method, the sample was dissolved in HNO_3+HCl+HF by microwave digestion, and As and Sb were pre-reduced by L-cysteine.The effects of HC1 and KBH_4 solution concentration and sample reduction treatment on determination results were investigated to obtain the optimal operation conditions of HG-AFS.The results showed that there was good linearity for As and Sb in 0-25 μg/L with correlation coefficient of 0.9999.The detection limits of As and Sb were 0.058 μg/L and 0.075 μg/L, respectively.The relative standard deviations(RSD)for 5 μg/L As and Sb were 0.71% and 0.78%(n=11), respectively.This method has been applied to the determination of titanium dioxide samples and the results were consistent with those obtained by ICP-AES, with the recoveries of 96%-108%.