激光光谱法研究水溶液中超铀核素化学形态现状

STATUS OF DETERMINING TRANSURANIC NUCLIDES SPECIATION IN AQUEOUS SOLUTION WITH LASER SPECTROMETRY

在高放废物地质处置研究中,超铀核素在水溶液中化学形态是研究超铀核素在地质介质中迁移行为的基础,而传统方法对于极低浓度下超铀核素化学形态研究较为困难。本文介绍了激光光谱法中的激光诱导光声光谱法(LIPAS)、激光诱导分解光谱法(LIBD)和时间分辨激光荧光光谱法(TRLFS)研究水溶液中超铀核素化学形态的现状并进行了分析,指出它们的优点是灵敏度高、非破坏性、非接触、可以实现在线实时研究,适合低浓度下超铀核素化学形态的研究,在高放废物地质处置研究中具有很好的应用前景。

The knowledge about speciation of transuranic nuclides in aqueous solution is a basis for understanding the chemical and migration behavior of transuranic nuclides in aqueous solution. The speciation of transuranic nuclides with trace concentration is complicated in near neutral aqueous solutions, including change of oxidation state, complexation and colloid generation, etc. The concentrations of transuranium in near neutral aqueous solution usually below the sensitivity range of method such as conventional absorption spectroscopy. The radioactive analysis method has a very low detection limits for radionuclides, however, it wouldn＇ t allow the direct measurement of the transuranic species. In contrast with these methods, laser spectroscopy is an ideal method with high sensitivity, and non-contact and non-destructive for determining the speciation of transuranic nuclides. This paper summarizes the status and application of LIPAS （Laser-induced Photoacoustic Spectrometry）, LIBD （Laser-induced Breakdown Detection） and TRLFS （Time-resolved Laser Fluorescence Spectrometry） to determine the speciation of transuranic nuclides with trace concentration in aqueous solutions.