高氯酸对土壤消解测定铅元素的影响

Effects of Perchloric Acid in Pd Element Determination in Soil

实验选取了具有代表性的4种土壤标物,考察了微波-电热板消解法处理土壤时高氯酸的存在对铅元素测定结果的影响。ICP-MS的测试结果表明,无论是否使用高氯酸对土壤进行前处理,不同土壤称样量下的铅元素测定均能取得满意的结果。扫描电子显微镜及XPS分析证明,土壤消解后产生的残渣不含铅元素,也不具备颗粒活性炭的多孔结构,其不会对铅元素测定的准确度产生影响。实验证明,使用微波-电热板法消解土壤测定铅元素的过程中,高氯酸的使用是可以避免的。

Four kinds of typical soil standard samples were selected to investigate the effects of perchloric acid on determining Pb element when the soil was pretreated by use of microwave-heating plate digestion.The testing of ICP-MS indicated there were a satisfied results about determining Pb in dfifferent weighing samples no matter whether the perchloric acid was added during the soil digestion.The SEM(scanning electric microscope)and XPS(X-ray photoelectron spectroscopy)analysis showed the residual particles in solution after the soil digestion did not contain Pb element and the porous construction which was of the characteristics of active carbon,thus the residual particles did not lead to the decrease of the accuracy of the Pb measuring.In general,the use of perchloric acid could be avoided during the process of soil digestion using microwave-heating plate in the determination of Pb element.