氢化物发生-原子荧光光谱法测定铝合金中痕量砷

Determination of trace arsenic in aluminum alloys by hydride generation-atomic fluorescence spectrometry

建立了测定铝合金中痕量砷HG-AFS分析方法。采用王水溶解样品，在硫脲和抗坏血酸的存在下将As（V）还原为As（Ⅲ），以KBH4溶液（20g／L）作为还原剂，HCl（5＋95）溶液作为载流，用原子荧光光谱法测定样品中痕量砷。在选定的实验条件下，方法的线性范围为0．05～40μL，线性回归方程为，f=108．17＋272．49p（μg／L），相关系数r=0．9997，检出限0．019μg/L。并与ICP-AES法进行了对照试验。

A convenient and accurate method for the determination of trace arsenic in aluminum alloys by hydride generation-atomic fluorescence spectrometry （HG-AFS） is presented. The sample was dissolved by aqua fortis and As（Ⅴ） was reduced to As（Ⅲ） in the presence of thiourea and ascorbic acid. Potassium borohydride solution （20 g/L） is used as a reductant and hydrochloric acid （5 ＋ 95） as a carder in this method. Under the optimal conditions, the fluorescence intensity is linearly proportional to the concentration of arsenic from 0.05 μg/L to 40 μg/L. The linear equation is If = 108.17 ＋ 272.49p （μg/L） with an excellent correlation coefficient of 0.9997, and the limit of detection is 0.019μg/L for arsenic. The results obtained by the proposed method were satisfactory compared with ICP-AES method.