导数原子捕集火焰原子吸收法测定粉煤灰中铅

Determination of trace lead in fly-ash by derivative atomic absorption spectrometry based on atom trapping technique

提出导数原子捕集火焰原子吸收测定粉煤灰中铅的方法。最佳条件下,该方法的特征浓度和检出限(3 min捕集)分别为0.56μg·L-1和1.5μg·L-1,较常规火焰法可分别改善783.9倍和104倍,相对标准偏差(n=10)和回收率分别为1.7％～5.3％和97.3％～104％。对GBW08401和82201标准粉煤灰分析验证和工业粉煤灰样品的分析获得满意结果。

A new method is presented for direct determination of trace lead in fly-ash using derivative atom trapping flame atomic absorption spectrometry. Under the optimal conditions, the characteristic concentration and detection limit (3σ) of lead are 0.56 μg·L-1and 1.5 μg·L-1espectively in 3 min, which are 783.9 and 104 times than those based on the conventional flame atomic absorption spectrometry. The method is applied to determine the lead in fly-ash with a recovery rate of 97.3%-104% and a relative standard deviation of 1.7%-5.3% (n=10). The results are satisfactory in the determination of standard fly-ash GBW08401 and 82201, industrial fly-ash samples as well.