海洋沉积物中16种稀土元素成分标准物质的研制

Development of Reference Materials of 16 Rare Earth Elements in Marine Sediments

本项目选择La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu、Sc、Y共16种稀土元素做为研究对象,研制海洋沉积物成分标准物质。海洋沉积物样品原样取自东海大陆架,样品风干后,经球磨制备成均匀的样品。采用激光粒度仪检测了样品的粒度分布,样品平均粒度均小于74μm(约200目)。由7家实验室采用不同原理的、可靠的ICP-AES、ICP-MS、XRF、AA等方法多种分析方法共同完成了16种稀土元素共108组定值测试,选择Sc元素作为特征元素,检验了样品的均匀性、稳定性,并以高灵敏度的ICP-AES、ICP-MS相配合确定了其最小取样量为100 mg。本实验给出了存放超过二十年的海洋沉积物样中16种稀土元素含量数值,与近海海洋沉积物标准物质的稀土成分进行对比,反应出稀土含量分布情况,以及长期以来海底稀土成分的变化。

In this project,a total of 16 rare earth elements La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu、Sc and Y are selected as the research objects to develop marine sediment composition reference materials.Marine sediment samples are taken from the continental shelf of the East China Sea.After air drying,the samples are prepared into uniform samples by ball grinding.The particle size distribution of the samples was detected by laser particle sizer,and the average particle size of the samples was less than 74μm(about 200 mesh).A total of 108 groups of characterization tests of 16 rare earth elements were completed by 7 laboratories using different principles and reliable ICP-AES,ICP-MS,XRF,AA and other analysis methods.Sc element was selected as the characteristic element to test the uniformity and stability of the sample,and the minimum sampling amount(100 mg)was determined by the combination of highly sensitive ICP-AES and ICPMS.This experiment gives the contents of 16 rare earth elements in marine sediment samples stored for more than 20 years.Compared with the rare earth components of offshore marine sediment reference materials,it reflects the distribution of rare earth contents and the changes of seabed rare earth components for a long time.