标題: Revisiting the Role of Dissolved Silicate in Catalyzing the Hydrogen Peroxide Process with Iron-Bearing Minerals

作者: Qiu, YC (Qiu, Yicheng); Sun, LK (Sun, Lingkai); Cui, JX (Cui, Jiaxin); Li, ZJ (Li, Zijun); Zeng, X (Zeng, Xiang); Liu, YX (Liu, Yuxiao); Alshawabkeh, AN (Alshawabkeh, Akram N.); Mao, XH (Mao, Xuhui)

來源出版物: ACS ES&T WATER DOI: 10.1021/acsestwater.2c00557 提前訪問日期: JUN 2023

摘要: The effects of dissolved silicate uponcatalyzing the hydrogenperoxide process by Fe(II) and Fe(III) minerals are radically different.

Injecting H2O2 into aquifers isa widelyused in situ chemical oxidation (ISCO) technology for groundwaterremediation. Dissolved silicate has been reported to decrease thereactivity of iron (III)-bearing minerals toward H2O2. In this study, the effect of naturally occurring levelsof dissolved silicate (& LE;1 mM) on the catalyzing hydrogen peroxide(CHP) with Fe(II) minerals is revaluated, and new observations thatcontradict previous studies are reported. Specifically, dissolvedsilicate enhances the CHP process with Fe(II) minerals. In the presenceof Fe(II) minerals, siderite and ferrous oxide (FeO), which had astronger dissolution tendency than Fe(III) minerals, dissolved silicatecould prevent the dissolved iron species from precipitation througha coordinating effect, therefore reinforcing the homogeneous CHP processand the degradation of 2,4-dichlorophenol. The solution pH decreaseddue to the generation of degradation intermediates, and the solutionacidification in turn promoted further dissolution of Fe(II) minerals.FeO particles exhibited the strongest silicate adsorption among theminerals; therefore, a higher initial silicate concentration of 1mM was needed to observe the enhancing effect. This study redefinesthe role of dissolved silicate in the CHP process and provides cluesto the design of an efficient H2O2-based ISCOsystem for the remediation of groundwater.

作者關鍵詞: silicate; coordinating effect; iron-bearingmineral; catalyzing hydrogen peroxide; groundwater; in situ chemical oxidation

地址: [Qiu, Yicheng; Li, Zijun; Zeng, Xiang; Mao, Xuhui] Wuhan Univ, Sch Resources & Environm Sci, Wuhan 430079, Peoples R China.

[Sun, Lingkai; Cui, Jiaxin] Changjiang Survey Planning Design & Res Co Ltd, Wuhan 430010, Peoples R China.

[Liu, Yuxiao] Hebei Delong Environm Engn Co, Baoding 071000, Peoples R China.

[Alshawabkeh, Akram N.] Northeastern Univ, Civil & Environm Engn Dept, Boston, MA 02115 USA.

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

Cui, JX (通訊作者)，Changjiang Survey Planning Design & Res Co Ltd, Wuhan 430010, Peoples R China.

電子郵件地址: whdxcjx@163.com; clab@whu.edu.cn

影響因子：5.3