水浴浸提-氢化物发生-原子荧光光谱法同时测定 地质样品中痕量砷和汞

水浴浸提-氢化物发生-原子荧光光谱法同时测定地质样品中痕量砷和汞

摘要: 采用盐酸-硝酸混合酸(盐酸-硝酸-水体积比3∶1∶4)水浴浸取地质样品,在样品消解后的母液中直接加入硫脲-抗坏血酸混合溶液,以氢化物发生-原子荧光光谱法同时测定地质样品中的痕量砷和汞。方法检出限为砷 0.0336 ng/mL,汞 0.0037 ng/mL;相对标准偏差(RSD,n=1)为砷1.1%,汞 3.0%。对国家一级标准物质GBW 07109~GBW 07114、GBW 07301~GBW 07312、GBW 07401~GBW 07408中的砷和汞进行测定,测定值与标准值相吻合。

Abstract: Geological sample was digested with mixed acid (V_HCl∶V_HNO₃∶V_H₂O=3∶1∶4) in water bath and then the mixed solution of thiourea and ascorbic acid as the reductant was directly added in the sample solution. The arsenic and mercury in the sample solution were determined simultaneously by hydride generation-atomic fluorescence spectrometry. The detection limits of the method for arsenic and mercury were 0.0336 ng/mL and 0.0037 ng/mL, respectively. The reliability of the method was tested by determination of arsenic and mercury in National Standard Reference materials of GBW 07109~07114, GBW 07301~07312, GBW 07401~07408. The results were in agreement with the certified values with precision of 1.1%RSD for As and 3.0%RSD for Hg.