Journal
JOURNAL OF HAZARDOUS MATERIALS
Volume 416, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.jhazmat.2021.126153
Keywords
Uranium; Solid wastes; Waste management; Re-adsorption mechanism; Remediation indication
Categories
Funding
- National Natural Science Foundation of China [41773011, 41873015]
- Guangdong Provincial Natural Science Foundation [2017A030313247, 2021A1515011588, 2021B1515020078]
- Science and Technology Planning Project of Guangdong Province, China [2020B1212060055]
- Scientific Research Projects in Colleges and Universities of Guangzhou Education Bureau, Guangzhou, China [201831803]
Ask authors/readers for more resources
The study comprehensively investigated the role of uranium re-adsorption behaviors during leaching tests with uranium mill tailings, revealing the influence of environmentally relevant factors on U re-absorption capacity and mechanism on UMTs with different particle sizes. The findings suggest that the environmental hazards and ecological risks of the U containing (waste) solids might have been underestimated due to the ignorance of the readsorption process, since the re-adsorbed U could be easily re-mobilized. Insights from this study are also helpful in developing effective in-situ remediation strategies.
Uranium mill tailings (UMTs) are one critical source of environmental U pollution. Leaching test has been extensively used to reveal U release capacity and mechanism from UMTs, while little attention has been paid to the effects of re-adsorption process on U release. In this study, the role of U re-adsorption behaviors during leaching test with UMTs was comprehensively investigated. Through paired data on mineralogical composition and aqueous U speciation, the influence of environmentally relevant factors on U re-absorption capacity and mechanism on UMTs with different particle sizes was revealed. Significant amounts of U re-adsorption were observed and primarily attributed to the adsorption on chlorite, albite and muscovite as well as combined reduction-sequestration by muscovite. Uranium re-adsorption predominantly occurred via inner-sphere complexation and surface precipitation depending on leachant pH. Coexisting sulfate or phosphate could further enhance U re-adsorption. The enhanced re-adsorption from sulfate occurred when inner-sphere complexation governed the re-adsorption process. These findings suggest that the environmental hazards and ecological risks of the U containing (waste) solids might have been underestimated due to the ignorance of the readsorption process, since the re-adsorbed U could be easily re-mobilized. The insights from this study are also helpful in developing effective in-situ remediation strategies.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available