水系沉积物重金属分析前处理方法

摘要

A pretreatment method for analysis of 6 heavy metals in stream sediment was set up in this paper,to study the impact of specimen preparation and digestion pretreatment on the determination results.The feasibility of this method was evaluated,and then it was used to determine the actual specimen.The results about Hg element test showed that the sediment particles of 0.147 mm could meet the analysis requirement.The digestion process using microwave,nitric acid,hydrochloric acid and hydrofluoric acid and the ICP-MS determination method are more suitable to make sure the precision and accuracy of the determination results of 6 heavy metals in the standard specimen of 5 different types of sediment.The established determination method was using for the determination of sediment specimen selected from the rivers,lakes and reservoirs in Guangxi province,the results showed that the RSD range of the 6 elements was from 1.57％ to 11.1％ and the adding standard recovery was more than 74.4％.%建立了水系沉积物中6种重金属分析的前处理方法,研究了样品粒径、消解前处理对测定结果的影响,对方法适用性作出评价,并对实际样品进行测定.结果表明:通过Hg元素含量的测定,粒径为0.147 mm的沉积物粒径可满足分析要求;采用微波-硝酸-盐酸-氢氟酸消解、ICP-MS法,对5种不同类型沉积物标准样品的6种重金属的测定结果显示,该方法精密度好、准确度高.利用建立的方法测定广西某河流湖库沉积物样品,6种元素测定结果RSD为1.57％～11.1％,加标回收率大于74.4％.