The remediation of uranium (U(VI)) contamination in water is of critical importance due to its chemical toxicity, long-term radiotoxicity, and environmental mobility. This study employed a green and efficient mechanical ball-milling method, using melamine as a nitrogen source, to successfully synthesize a nitrogen-modified zerovalent iron material (N-ZVIbm). Systematic characterization, revealed that the ball-milling process successfully constructed Fe–Nx coordination structures on the ZVI surface. This structure optimized the electronic distribution of zerovalent iron and enhanced its surface reactivity. Batch experiments demonstrated that the U(VI) removal by N-ZVIbm follows pseudo-first-order kinetics, exhibiting a rate constant as high as 0.288 h−1, which is 3.7 times that of unmodified ball-milled zerovalent iron (ZVIbm). Mechanistic studies revealed that the Fe–Nx sites not only promoted the corrosion of ZVI, accelerating the formation of adsorptive iron(III) (oxyhydr) oxides, but also functioned as highly efficient adsorption and electron transfer sites, synergistically enhancing both the adsorption and reduction of U(VI). Post-reaction solid analysis indicated a U(IV) content of up to 68%, markedly exceeding that in the control system (29%), confirming the efficacy of nitrogen modification in enhancing U(VI) reduction and immobilization. This work not only establishes a novel green pathway for synthesizing high-performance zerovalent iron materials but also deepens the understanding of the mechanisms of Fe–Nx structures in radionuclide remediation.
- Open Access
- Article
Enhanced Removal of Uranium(VI) by Nitrogen-Modified Zerovalent Iron Synthesized via Mechanochemically Ball Milling
- Lianjie Ma 1,2,
- Peng Fan 2,*,
- Kunming Hou 2,
- Zhengwu Liu 3,
- Meng Du 2,
- Chen Tian 2,
- Zhenye Liang 3,
- Bing Nan 2,
- Luozhen Jiang 2,
- Lingling Guo 2,
- Yulin Qin 2,
- Zhuofan Zhang 2,
- Jisong Mi 2,
- Yingpeng Xie 1,*,
- Lina Li 2,3,*
Author Information
Received: 15 Jan 2026 | Revised: 17 Mar 2026 | Accepted: 18 Mar 2026 | Published: 30 Mar 2026
Abstract
Graphical Abstract
Keywords
zerovalent iron | ball milling | uranium removal | X-ray absorption fine structure | wastewater remediation
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