标题: Highly Selective Reduction of Nitrate by Zero-Valent Aluminum (ZVAI) Ball-Milled Materials at Circumneutral pH: Important Role of Microgalvanic Cells for Depassivation of ZVAl and N2-Selectivity

作者: Li, Y (Li, Yan); Mao, XH (Mao, Xuhui); Chen, CQ (Chen, Chaoqi); Zhang, LY (Zhang, Lieyu); Liu, WJ (Liu, Wenjie); Wang, X (Wang, Xu); He, L (He, Lang); Xu, T (Xu, Tao)

来源出版物: ENVIRONMENTAL SCIENCE & TECHNOLOGY DOI: 10.1021/acs.est.2c09727 提前访问日期: FEB 2023

摘要: The passivation of zero-valent aluminum (ZVAl) limits its application in environmental remediation. Herein, a ternary composite material Al-Fe-AC is synthesized via a ballmilling treatment on a mixture of Al0, Fe0, and activated carbon and a nitrogen (N2)-selectivity of > 75%. The mechanism study reveals that, in the initial stage, numerous Al//AC and Fe//AC microgalvanic cells in the Al-Fe-AC material could lead to a local alkaline environment in the vicinity of the AC cathodes. The local alkalinity depassivated the Al0 component and enabled its continuous dissolution in the subsequent second stage of reaction. The functioning of the AC cathode of the Al//AC microgalvanic cell is revealed as the primary reason accounting for the highly selective reduction of nitrate. The investigation on the mass ratio of raw materials manifested that an Al/Fe/AC mass ratio of 1:1:5 or 1:3:5 was preferable. The test in simulated groundwater suggested that the as-prepared Al-Fe-AC powder could be injected into aquifers to achieve a highly selective reduction of nitrate to nitrogen. This study provides a feasible method to develop high-performance ZVAl-based remedial materials that could work in a wider pH range.

作者关键词: zero -valent aluminum; nitrate reduction; nitrogen selectivity; microgalvanic cells; local alkalinity

KeyWords Plus: ELECTROCATALYTIC REDUCTION; CHEMICAL REMOVAL; WATER; IRON; DEGRADATION; PERFORMANCE; MECHANISM; BROMATE; SYSTEMS; SCRAP

地址: [Li, Yan; Mao, Xuhui; Chen, Chaoqi; Wang, Xu; Xu, Tao] Wuhan Univ, Sch Resources & Environm Sci, Wuhan 430079, Peoples R China.

[Zhang, Lieyu] Chinese Res Inst Environm Sci, Beijing 100012, Peoples R China.

[Zhang, Lieyu; He, Lang] Franklin & Marshall Coll, Dept Earth & Environm, Lancaster, PA 17604 USA.

通讯作者地址: Mao, XH (通讯作者)，Wuhan Univ, Sch Resources & Environm Sci, Wuhan 430079, Peoples R China.

Zhang, LY (通讯作者)，Chinese Res Inst Environm Sci, Beijing 100012, Peoples R China.

Zhang, LY (通讯作者)，Franklin & Marshall Coll, Dept Earth & Environm, Lancaster, PA 17604 USA.

电子邮件地址: clab@whu.edu.cn; zhangly@craes.org.cn

影响因子：11.357