微波消解体系与聚四氟乙烯滤膜对PM_(2.5)中重金属测定的影响

Effect Microwave Digestion System and PTFE Filter on Quantitative Research of Heavy Metals in PM_(2.5)

采用4种微波消解体系对聚四氟乙烯（ PTFE）材质滤膜采集的PM2．5样品进行消解，利用电感耦合等离子体质谱（ ICP-MS）测定样品中Cr、Mn、Cu、As、Cd 5种重金属元素含量，并计算其空白加标和样品加标回收率，建立了测定PTFE材质滤膜采集的PM2．5样品中重金属元素的最优微波消解体系。结果表明，4种消解体系下，空白加标回收率和样品加标回收率均处于合理范围，分别为95.3％～116.3％和93.3％～118.5％。其中，HNO3放置过夜＋H2 O2消解体系具有空白值低、测定稳定性强、操作简便、绿色环保、对人体健康危害小等优点，能够满足大批量PM2．5样品中重金属总量的快速、高效、准确分析的要求。

Four kinds of microwave digestion system were studied to digest the PM2. 5 samples collected with PTFE filter. The content of Cr、Mn、Cu、As、Cd in the samples were determined by ICP-MS under optimized conditions. Meanwhile, the recovery rates of blank and samples in standard addition were calculated. Finally, the optimal digestion system to digest PM2. 5 sample collected with PTFE filter was established. The results showed that both of the recovery rates of blank and samples in standard addition under the four kinds of digestion system were basically in a reasonable range, which were between 95. 3%-116. 3% and 93. 3%-118. 5%, respectively. However, the digestion system of HNO3 （ placed overnight after added） ＋ H2 O2 could be best satisfied with the demand of rapid, efficient and accurate analysis of the total quantities of heavy metals on a large scale of PM2. 5 samples because of the advantages of low blank value, better stability of determination, easy to operate, green environmental protection, less harmful to health and so on.