提出了氢化物发生-原子荧光光谱法测定核电用钢中痕量锡的方法。样品在酒石酸溶液存在下,用盐酸-硝酸(3+1)混合酸溶解,用50 g·L-1硫脲-抗坏血酸混合溶液作掩蔽剂,20 g·L-1硼氢化钾溶液作为锡(Ⅳ)的还原剂,氢化反应在pH 5.0~5.5介质中进行,锡的质量浓度在50 μg·L-1范围以内与相应的荧光强度呈线性关系,方法的检出限(3s/k)为0.4 μg·L-1。应用此方法分析了核电用钢及不锈钢标准样品中锡的含量,并与电感耦合等离子体原子发射光谱法作了比较,测定值与标准值相符,结果的相对标准偏差(n=8)均小于4.5%。

Trace amount of tin in nuclear power steels was determined by HG-AFS. Sample was dissolved with mixed acid of HCl-HNO3(3+1) in the presence of tartaric acid. Mixed solution of 50 g·L-1 thiourea and ascorbic acid was used as masking agent and 20 g·L-1 potassium borohydride was used as reductant. The generation of SnH4 was carried out in a medium of pH 5.0-5.5. Linear relationship between values of fluorescence intensity and mass concentration of tin was kept in the range within 50 μg·L-1, with detection limit (3s/k) of 0.4 μg·L-1. The proposed method was applied to the determination of trace amount of tin in samples of nuclear power steels and standard samples of stainless steels, the results obtained were in consistency with the certified values and also with the results found by ICP-AES, giving values of RSD′s (n=8) less than 4.5%.