电感耦合等离子体原子发射光谱法测定活性炭中铁锌钙镁铅

活性炭样品经550 ℃高温焙烧后,以硝酸、氢氟酸和盐酸的混酸作为消解试剂,用微波消解法消解,电感耦合等离子体原子发射光谱法(ICP-AES)测定消解液中铁、锌、钙、镁和铅金属元素含量。试验结果表明:样品经高温焙烧后基体元素碳已除去,对测定没有干扰,因此可以直接用待测元素的标准溶液绘制校准曲线,不需要进行基体匹配。共存元素由于含量很低,在所选定的分析线下测定也没有干扰。方法的检出限如下:铁为0.02 μg/mL,锌为0.01 μg/mL、钙为0.01 μg/mL、镁为0.02 μg/mL,铅为0.05 μg/mL。样品测定结果的相对标准偏差(RSD)在1.7%～4.1%之间(n=9),回收率在94%~96%之间。

Determination of iron,zinc,calcium,magnesium and lead in activated carbon by inductively coupled plasma atomic emission spectrometry

The activated carbon sample was digested by microwave in a mixed acid system (nitric acid+ hydrofluoric acid + hydrochloric acid) after being calcinated at 550 ℃. Then, Fe, Zn, Ca, Mg and Pb in the digestion solution were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The experiment showed that, after high temperature calination, the matrix element carbon in the sample was removed without interference in the determination, so the standard solution of testing elements could be directly used to establish calibration curve without matrix matching. Since the content of coexisting elements in the sample was rather low they also had little interference with the determination under selected analytical lines. The limit of detection was as follows: 0.02 μg/mL for Fe, 0.01 μg/mL for Zn, 0.01 μg/mL for Ca, 0.02 μg/mL for Mg and 0.05 μg/mL for Pb. The relative standard deviations (RSDs) were 1.7%-4.1% (n=9), and the recoveries were 94%-96%.