Effects of in situ leaching on the origin and migration of rare earth elements in aqueous systems of South China: Insights based on REE patterns, and Ce and Eu anomalies

Xiao-Rui Liu; Wen-Shen Liu; Ye-Tao Tang; Shi-Zhong Wang; Ying-Jie Cao; Zi-Wu Chen; Can-Die Xie; Chang Liu; Mei-Na Guo; Rong-Liang Qiu

doi:10.1016/j.jhazmat.2022.128959

Effects of in situ leaching on the origin and migration of rare earth elements in aqueous systems of South China: Insights based on REE patterns, and Ce and Eu anomalies

J Hazard Mater. 2022 Aug 5:435:128959. doi: 10.1016/j.jhazmat.2022.128959. Epub 2022 Apr 20.

Authors

Affiliations

¹ School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, China; Guangdong Provincial Engineering Research Center for Heavy Metal Contaminated Soil Remediation, Sun Yat-sen University, Guangzhou, China.
² School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, China; Guangdong Provincial Engineering Research Center for Heavy Metal Contaminated Soil Remediation, Sun Yat-sen University, Guangzhou, China. Electronic address: liuwsh8@mail.sysu.edu.cn.
³ School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, China.
⁴ School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China; Guangdong Provincial Key Laboratory of Agricultural and Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.

PMID: 35483265
DOI: 10.1016/j.jhazmat.2022.128959

Abstract

In situ leaching of ion-adsorption rare earth element (REE) deposits has released large amounts of REE-containing wastewater. However, the origin, speciation, distribution and migration of REEs in aqueous systems of the mining catchment are poorly understood. Groundwater, surface water, in situ leachates and weathered granite soil samples were collected from a catchment affected by mining activities in South China. The REE concentrations in groundwater (6.18 × 10^-3-0.49 μmol L^-1) and surface water (2.54-44.05 μmol L^-1) decreased from upstream to downstream. REEs in groundwater were detected in organic matter associated (FA-REE) colloids, while the REE³⁺ and REE(SO₄)⁺ were converted to REE(CO₃)⁺ and FA-REE colloids from leachates and upstream surface water to downstream. The REE patterns of leachates and upstream groundwater (light and middle REE enrichment) resembled those of soil, but showed heavy REE enrichment due to FA-REE colloids in the downstream. REE in surface water were derived from middle REE enriched leachate. The Ce and Eu anomalies in the water samples indicated the REE origin (i.e., mining activities) and the hydrological variations (e.g., oxidation environment and water-rock interaction). Our results reveal the origin and fate of REE in aqueous systems of ion-adsorption REE mining catchments.

Keywords: Eu anomaly; Groundwater; Ion-adsorption REE mine; REE colloid; REE fractionation.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

China
Environmental Monitoring* / methods
Metals, Rare Earth*
Mining
Soil
Water

Substances

Metals, Rare Earth
Soil
Water