氢化物发生-原子荧光光谱法测定铁鳞中砷和汞

Determination of arsenic and mercury in mill scale by hydride generation-atomic fluorescence spectrometry

建立了氢化物发生-原子荧光光谱法同时测定铁鳞中砷和汞的新方法。样品采用盐酸(1+1)分解,加入硫脲-抗坏血酸混合溶液作为还原剂和掩蔽试剂,以氢化物发生-原子荧光光谱法进行检测。详细研究了样品酸度、硫脲-抗坏血酸浓度、还原时间、硼氢化钾浓度、载流、基体效应等因素对测定结果的影响,并确定了最佳检测条件。本方法砷和汞的检出限分别为0.036μg/g和0.010μg/g;相对标准偏差(RSD)分别为5.1%和8.8%(n=11,As为1μg/g,Hg为0.2μg/g),回收率介于95%～110%之间。

A new method has been developed for the determination of arsenic and mercury in mill scale by hydride generation atomic fluorescence spectrometry.The samples were digested by HCl（1＋1）,and arsenic and mercury in sample were determined by hydride generation atomic fluorescence spectrometry with addition of thiourea-ascorbic acid mixed solution as reductant and masking reagent.The influencing factors were investigated,including the sample acidity,thiourea-ascorbic acid concentration,reduction time,potassium borohydride concentration,carrier and matrix effect,and the optimal determination conditions were obtained.The detection limits of the method for As and Hg were 0.036 μg/g and 0.010 μg/g,respectively.The relative standard deviations were 5.1% and 8.8%,respectively（n=11,As 1 μg/g,Hg 0.2 μg/g）,and the recoveries were in the range of 95%-110%.