LA-ICP-MS测定单颗粒氨基膦酸螯合树脂中的铀分布

Determination of Uranium Distribution in Amino Phosphonic Acid Chelating Resin by LA-ICP-MS

以利用氨基膦酸螯合树脂从湿法磷酸(WPA)中回收铀为研究背景,对单颗粒氨基膦酸螯合树脂中铀分布进行研究,得到以下结论:确定激光剥蚀电感耦合等离子体质谱仪(LA-ICP-MS)最佳的激光频率为6 Hz、束斑直径为44μm、能量密度为6 J/cm^(2)。选择吸附饱和的树脂和洗脱完全的树脂分别作为吸附和淋洗过程的外标,对其进行均匀性测试,吸附饱和树脂中铀含量的相对标准偏差为3.87%(n=9),洗脱完全树脂中铀含量的相对标准偏差为3.52%(n=9),均一性良好。利用LA-ICP-MS对氨基膦酸螯合树脂中的铀进行原位微区分析,结果表明:铀在树脂上的吸附过程是由外向内逐渐完成,淋洗过程是由外向内逐渐完成,树脂内外铀浓度逐渐均匀统一,最终达到吸附饱和和淋洗完全。

In this paper,based on the research background of recovering uranium from wet-process phosphoric acid(WPA)by amino phosphonate acid chelating resin,the distribution of uranium in single particle amino phosphonate chelating resin was studied.The results show that the optimal laser frequency of LA-ICP-MS is determined to be 6 Hz,the beam spot diameter is 44μm,and the energy density is 6 J/cm^(2).The resin with saturated adsorption and the resin with complete elution were selected as the external standard of the adsorption and leaching process,and the homogeneity test was carried out.The relative standard deviation of uranium content in the resin with saturated adsorption and the resin with complete elution are 3.87%and 3.52%(n=9),respectively.Uniformity is good.In situ microzone analysis of uranium in amino phosphonic acid chelating resin was carried out by LA-ICP-MS.The adsorption process of uranium on the resin is gradually completed from the outside to the inside,and the leaching process is gradually completed from the outside to the inside,and the concentration of uranium inside and outside the resin is gradually uniform and unified,and finally reaches adsorption saturation and leaching complete.