原子吸收分光光度法测定铅的两种前处理方法比较研究

Comparative study of 2 kinds of different pretreatments in determination of lead by atomic absorption spectrophotometry

目的探讨干法灰化和湿法消解2种方式对测铅处理的影响。方法用2个不同浓度的铅标准溶液作为样品,采用干法灰化与湿法消解对其进行前处理,并用原子吸收分光光度计进行检测,通过计算回收率和采用统计技术中经典Z值来确定2种方式的优劣。结果干法灰化平均回收率87.52%,回收率在85.45%~88.75%之间;湿法消解平均回收率99.03%,回收率在96.12%~102.35%之间。通过对2种方法的回收率进行经典Z值计算,干法灰化的Z值是10.14,不可接受;湿法消解的Z值是0.44,结果良好。结论证明湿法消解比干法灰化的效果更好。

Objective To discuss the influence of the 2 kinds of ways of dry ashing and wet digestion to measure lead processing. Methods Dry ashing and wet digestion were used as pretreatment with 2 kinds of different concentrations of lead standard solution as the sample, and tested by atomic absorption spectrophotometry; the calculation of recovery and statistical techniques in classic Z value were used to determine the merits of the 2 kinds of ways. Results Dry ashing average recovery was 87.52%, the recovery was between 85.45%~88.75%; Wet digestion average recovery was 99.03%, the recovery was between 96.12%~102.35%. Through the Z value calculation of recovery rate of the 2 kinds of methods, Z value was 10.14 by dry ashing, and it was not acceptable; Z value was 0.44 by wet digestion, and the result was good. Conclusion It was proved that the result of wet digestion was better than that of dry ashing.