Arsenic Adsorption on Lanthanum-Impregnated Activated Alumina: Spectroscopic and DFT Study.
Arsenic Adsorption on Lanthanum-Impregnated Activated Alumina: Spectroscopic and DFT Study.
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砷在掺镧活性氧化铝上的吸附：光谱和 DFT 研究。
DOI：
10.1021/acsami.5b08730
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发表时间：
2015-11
期刊：
影响因子：
--
通讯作者：
Jing Chuanyong
中科院分区：
文献类型：
--
作者：
Shi Qiantao;Yan Li;Chan Tingshan;Jing Chuanyong
Rare earth-modified adsorbents (REMAs) have been widely used to remove oxyanion pollutants from water, including arsenic (As). However, the molecular-level structural information and reactions at the liquid/solid interface are still murky, which limits the design of applicable REMAs. Herein, a lanthanum-impregnated activated alumina (LAA) was synthesized as a representative REMA, and its As uptake mechanisms were explored using multiple complementary characterization techniques. Our adsorption experiments showed that LAA exhibited 2-3 times higher As adsorption capacity than AA. In contrast to the bidentate configuration formed on most metal oxide surfaces, our EXAFS and DFT results suggest that As(III) and As(V) form monodentate surface complexes on LAA through As-O-La coordinative bonding. In situ flow cell ATR-FTIR observed a strong dependence of As-O peak positions on pH, which could be interpreted as the change in the fractions of As(V) surface complexes with zero- to double-protonation on LAA, AA, and LaOOH. As(V) on LAA existed as singly and doubly protonated surface species, and the pKa of transition from double to single protonation (∼5.8) was lower than that for its soluble counterpart (6.97). The surface reaction and structural configuration were incorporated in a CD-MUSIC model to satisfactorily predict macroscopic As adsorption behaviors. The insights gained from the molecular-level reactions shed light on the design and application of REMAs in environmental remediation for As and its structural analogues.
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影响因子：
13.6
作者：
Yu Zhang;Xiao-min Dou;Min Yang;Hong He;Chang Jing;Zi-Yu Wu
通讯作者：
Yu Zhang;Xiao-min Dou;Min Yang;Hong He;Chang Jing;Zi-Yu Wu
影响因子：
8.4
作者：
D. Setyono;S. Valiyaveettil
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3.9
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Kubicki, James D.;Paul, Kristian W.;Strongin, Daniel R.
通讯作者：
Strongin, Daniel R.
影响因子：
8.6
作者：
Kuroda, Yoshiyuki;Miyamoto, Yumi;Mizuno, Noritaka
通讯作者：
Mizuno, Noritaka
影响因子：
8.6
作者：
Lebed, Pablo J.;Savoie, Jean-Daniel;Kleitz, Freddy
通讯作者：
Kleitz, Freddy