石墨消解-火焰原子吸收光谱法测定土壤和沉积物中铅

Determination of lead in soil and sediment by Graphite digestion - Flame atomic absorption spectrometry

建立了用石墨消解仪消解样品,火焰原子吸收光谱法测定土壤和沉积物中重金属铅含量的方法。以盐酸-硝酸-氢氟酸-高氯酸作为消解体系,样品经石墨消解后以1%硝酸定容,采用火焰原子吸收光谱仪进行测定。铅的质量浓度在0.00~10.0mg/L范围内与吸光度具有良好线性关系,相关系数为0.9994,方法检出限为7μg/g。测定结果的相对标准偏差为3.9%~5.1%(n=6),样品加标回收率为87.5%~103%。测定了土壤和沉积物标准样品,测定值均在标准值可接受范围内。该方法操作简单、快速,结果准确、可靠,适用于土壤和沉积物样品高含量铅的测定。

A method for determination lead (Pb) in soil and sediment was established by graphite digestion - flame atomic absorption spectrometry(FAAS). The sample was dissolved by hydrochloric acid, nitric acid, hydrofluoric acid and perchloric acid, then diluted to volume by 1% nitric acid solution.Good linearity were between absorbance and mass concentration of 0.00~10.0 mg/L with the correlation coefficient of 0.9994. The method detection limit was 7μg/g. The relative standard deviation of practical sample testing varied from 3.9% to 5.1%(n=6), and the recoveries were between 87.5% and 103%. The measurements of soil and sediment standard samples were within the uncertainty of certified values. This method had high accuracy, and was applicable for determining high levels of lead in soil and sediment.