Distribution and mode of occurrence of uranium in bottom ash derived from high-germanium coals

作     者：Yinglong Sun Guangxia Qi Xuefei Lei Hui Xu Lei Li Chao Yuan Yi Wang 

作者机构：Department of Environmental Engineering School of Environment Tsinghua University Department of Environmental Science and Engineering School of Food and Chemical EngineeringBeijing Technology and Business University 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2016年第28卷第5期

页      面：91-98页

核心收录：

学科分类：0830[工学-环境科学与工程（可授工学、理学、农学学位）] 083001[工学-环境科学] 08[工学] 

基　　金：financial support from the Talent Support Fund of Tsinghua University (No. 413405001) 

主　　题：Coal bottom ash Uranium Radioactivity Tessier sequential extraction Magnetic separation 

摘      要：The radioactivity of uranium in radioactive coal bottom ash（CBA） may be a potential danger to the ambient environment and human health. Concerning the limited research on the distribution and mode of occurrence of uranium in CBA, we herein report our investigations into this topic using a number of techniques including a five-step Tessier sequential extraction, hydrogen fluoride（HF） leaching, Siroquant（Rietveld） quantification, magnetic separation, and electron probe microanalysis（EPMA）. The Tessier sequential extraction showed that the uranium in the residual and Fe–Mn oxide fractions was dominant（59.1%and 34.9%, respectively）. The former was mainly incorporated into aluminosilicates,retained with glass and cristobalite, whereas the latter was especially enriched in the magnetic fraction, of which about 50% was present with magnetite（Fe_3O_4） and the rest in other iron oxides. In addition, the uranium in the magnetic fraction was 2.6 times that in the non-magnetic fraction. The experimental findings in this work may be important for establishing an effective strategy to reduce radioactivity from CBA for the protection of our local environment.