大气颗粒物中铬形态的系统分析

System analysis of Cr speciations of atmospheric particulate matters

为了对大气颗粒物中的铬形态进行系统分析,建立一套简单的大气颗粒物中铬形态的分析方法;测定铬总含量,采用Tessier法测定铬的可交换态、碳酸盐结合态、有机结合态、残渣态、铁锰氧化物结合态;用p H值为9.5的碳酸钠-碳酸氢钠缓冲溶液处理大气颗粒物提取液,同时对中国北方几个乡镇的大气颗粒物中铬的形态进行分析。结果表明:铬的回收率达75.4%~104.31%;Cr的总浓度约为172.21 ng/m L,Cr^(6+)浓度为169.28 ng/m L,Cr^(3+)浓度为2.99 ng/m L;Cr^(6+)和Cr^(3+)测定的RSD分别为8.76%和17.68%。

In order to make a systematic analysis on the speciations of chromium in atmospheric particulate matter, a simple analysis system was established for chromium speciations of atmospheric particulates. Firstly, the total concentration was determined, then five chromium speciations were determined by Tessier method,including exchangeable state, bound to carbonates, bound to organic matters and residual, bound to Fe-Mn. With p H=9.5 Na2CO3-Na HCO3 buffer solution processing of atmospheric particulate matter extracts, Cr speciations in atmospheric particulate matter of several villages in the north of China was analyzed. The results show that the recovery rate of Cr is 75.4% ～104.31%,the total concentration of Cr is 172.21 ng/m L, Cr^6＋ concentration is169.28 ng/m L, and the Cr^3＋ concentration is 2.99 ng/m L,the RSD of Cr^6＋ and Cr^3＋ are 8.76% and 17.68% respectively.