摘要
Uranium is an environmentally hazardous element,and is commonly present at trace levels(2.4 μg/g for world coals)in coal deposits.However,selected coal deposits could be highly enriched in uranium.In this study,15 coal samples were collected from Eastern Yunnan coal deposits,China,aiming to characterize the distribution and the occurrence of uranium in those coals.In studied samples,uranium content varied from 0.36 to 8.28 μg/g,with an average value of 3.76 lg/g.Generally,uranium content in coals from northern coal mines(3.02±2.44 μg/g,n=5)were lower than it in southern coal mines(4.13±2.30 μg/g,n=10).Uranium in coal samples showed no obvious correlation with total sulfur,whereas was positively correlated with ash yield.The results of sequential chemical extraction procedure confirm that organic-bound is the dominant occurrence of uranium.The slight enrichment of uranium in studied coals was probably attributed to sedimentation processes,hydrological conditions and tectonic structure of the coal deposits.
基金
This work was supported by the National Basic Research Program of China(2014CB238903)
the National Natural Science Foundation of China(41173032,41371444,41373110)
the open project of Anhui Key Laboratory(ZYZWSW2014011)
Anhui Provincial Department of Education University Scientific Research Project(KJ2020A1204).We acknowledge editors and reviewers for polishing the language of the paper and for in-depth discussion.
