Ternary surface complexation promotes simultaneous removal of arsenic and uranium by TiO <sub>2</sub>
The co-occurrence of arsenic and uranium in groundwater has been found in many countries, posing a significant challenge to human health. Here, we have demonstrated the efficient simultaneous removal of arsenic and uranyl-carbonate complexes from groundwater using {001}-TiO<sub>2</sub>. Surprisingly, the presence of U(VI) greatly enhanced the adsorption of As(V) on {001}-TiO<sub>2</sub>, while As(V) had a negligible impact on U(VI) adsorption. Through in situ ATR-FTIR spectroscopy, we uncovered a mechanism involving the formation of a ternary surface complex [Ti-U(VI)-As(V)] on the surface of {001}-TiO<sub>2</sub>. This ternary surface complex formed through the substitution of CO<sub>3</sub><sup>2-</sup> from uranyl coordination sites. Furthermore, the adsorbed As(V) and U(VI) can be easily recovered using a sodium hydroxide solution, and {001}-TiO<sub>2</sub> can be used repeatedly. Our findings offer a promising solution for the simultaneous removal of As(V) and U(VI) from groundwater and provide valuable insights into the mechanisms involved in their removal.
Authors
- Leiming Lin
- Ying Meng (ORCID: https://orcid.org/0000-0002-5889-476X)
- Fubo Luan (ORCID: https://orcid.org/0000-0001-6540-8101)
- Zheng Li (ORCID: https://orcid.org/0000-0003-3290-4613)
- Jun Ren (ORCID: https://orcid.org/0000-0002-0781-730X)
Institutions
- North University of China (CN)
- Chinese Academy of Sciences (CN)
- Research Center for Eco-Environmental Sciences (CN)
- University of Chinese Academy of Sciences (CN)
Publication Details
- Journal
- Proceedings of the National Academy of Sciences
- Published
- 2025-03-20
- DOI
- https://doi.org/10.1073/pnas.2501354122
- Citations
- 1
- Primary Topic
- Radioactive element chemistry and processing
- Type
- article
- Field-Weighted Citation Impact
- 0.54
Funders
- National Natural Science Foundation of China
- National Key Research and Development Program of China