土壤样品的微波消解及其痕量铀的分析  

DETERMINATION OF TRACE URANIUM IN FIVE SOIL SAMPLES DIGESTED BY MICROWAVE

作　　者：张继龙[1] 王林博[1] 张小枝[1] 何周国[1] 谈树苹[1] 

机构地区：[1]中国原子能科学研究院放射化学研究所,北京102413

出　　处：《核化学与放射化学》2003年第4期223-227,共5页Journal of Nuclear and Radiochemistry

摘　　要：对3个土壤样和2个放射性河床沉积物的国家标准物质进行了微波消解,又采用TOPO萃取和液体荧光法分析了样品中的铀含量,并将分析结果与国家标准方法GB11220 2—89的分析结果进行了比较。结果表明,微波消解法与国家标准方法一样,均不能实现土壤的全部消解,但与国家标准方法相比较,微波消解速度快,所需试剂量少,且易于实现定量控制,铀回收率高,分析精度高。对不溶物进行X射线能谱分析发现,其主要组成为铝、钛及过渡金属的氟化物或氧化物。同位素质谱分析表明,国家标准物质GBW08304中的234U,235U均比天然丰度低,另一个国家标准物质GBW08304a中铀的同位素分布与天然组成基本一致。Three soil samples and two radioactive river sediments are digested by microwave. Uranium in samples is extracted by TOPO and determined by liquid fluorimetry.The uranium isotope distribution in the two radioactive samples is measured by HP-ICP-MS. Compared with Chinese standard method GB11220.2-89, the procedure tried in this work is faster with less reagents. The recovery of uranium is higher and the precision of determination is also better. The determined abundance of)~234)U and)~235)U in GBW08304a is almost as same as the natural uranium. While the lighter isotopes of uranium in GBW08304 are somewhat depleted. The undigestable part of soil sample GBW-07404-GSS-4, explored by scanning electron microscope with EDS, is found to be composed of F,O,Al,Cu,Ti,etc.

关 键 词：放射性物质 土壤 微波消解 铀 痕量分析 含量测定 同位素丰度 TOPO萃取 液体荧光法 环境监测 

分 类 号：X833[环境科学与工程—环境工程] TL751[核科学技术—辐射防护及环境保护]