Metal(loid)s removal by zeolite-supported iron particles from mine contaminated groundwater: Performance and mechanistic insights

Ping Wang; Xiangke Kong; Lisha Ma; Shizhong Wang; Wei Zhang; Le Song; Hui Li; Yanyan Wang; Zhantao Han

doi:10.1016/j.envpol.2022.120155

Metal(loid)s removal by zeolite-supported iron particles from mine contaminated groundwater: Performance and mechanistic insights

Environ Pollut. 2022 Nov 15:313:120155. doi: 10.1016/j.envpol.2022.120155. Epub 2022 Sep 18.

Authors

Ping Wang¹, Xiangke Kong², Lisha Ma³, Shizhong Wang⁴, Wei Zhang⁵, Le Song⁶, Hui Li⁷, Yanyan Wang⁸, Zhantao Han⁹

Affiliations

¹ Institute of Hydrogeology & Environmental Geology, CAGS, Shijiazhuang, 050061, China; Fujian Provincial Key Laboratory of Water Cycling and Eco-Geological Processes, Xiamen, 361021, China. Electronic address: pingwang@mail.cgs.gov.cn.
² Institute of Hydrogeology & Environmental Geology, CAGS, Shijiazhuang, 050061, China; Key Laboratory of Groundwater Remediation of Hebei Province and China Geological Survey, Shijiazhuang, 050061, China. Electronic address: kongxiangke@mail.cgs.gov.cn.
³ Institute of Hydrogeology & Environmental Geology, CAGS, Shijiazhuang, 050061, China; Key Laboratory of Groundwater Remediation of Hebei Province and China Geological Survey, Shijiazhuang, 050061, China. Electronic address: malisha@mail.cgs.gov.cn.
⁴ School of Environmental Science and Engineering, Guangdong Provincial Key Lab of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, China. Electronic address: wshizh2@mail.sysu.edu.cn.
⁵ Institute of Hydrogeology & Environmental Geology, CAGS, Shijiazhuang, 050061, China; Key Laboratory of Groundwater Remediation of Hebei Province and China Geological Survey, Shijiazhuang, 050061, China. Electronic address: zhangwei@mail.cgs.gov.cn.
⁶ Institute of Hydrogeology & Environmental Geology, CAGS, Shijiazhuang, 050061, China; Key Laboratory of Groundwater Remediation of Hebei Province and China Geological Survey, Shijiazhuang, 050061, China. Electronic address: songle@mail.cgs.gov.cn.
⁷ Institute of Hydrogeology & Environmental Geology, CAGS, Shijiazhuang, 050061, China; Key Laboratory of Groundwater Remediation of Hebei Province and China Geological Survey, Shijiazhuang, 050061, China. Electronic address: lihui.107@163.com.
⁸ Institute of Hydrogeology & Environmental Geology, CAGS, Shijiazhuang, 050061, China; Key Laboratory of Groundwater Remediation of Hebei Province and China Geological Survey, Shijiazhuang, 050061, China. Electronic address: wangyanyan@mail.cgs.gov.cn.
⁹ Technical Centre for Soil, Agriculture and Rural Ecology and Environment, Ministry of Ecology and Environment, Beijing, 100012, China. Electronic address: hanzhantao1977@163.com.

PMID: 36130632
DOI: 10.1016/j.envpol.2022.120155

Abstract

Iron-based materials have been widely investigated because of their high surface reactivity, which has shown potential for the remediation of metal(loid)s in groundwater. However, the disadvantages of structural stability and economic feasibility always limit their application in permeable reactive barrier (PRB) technology. In this study, zeolite-supported iron particles (Zeo-Fe) were synthesized by an innovative low-cost physical preparation method that is suitable for mass production. The removal efficiency and mechanism of typical metal(loid)s (Pb²⁺, Cd²⁺, Cr⁶⁺ and As³⁺) were subsequently investigated using various kinetic and equilibrium models and characterization methods. The results of scanning electron microscopy and energy dispersive spectrometry (SEM-EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) confirmed that zero valent iron (Fe⁰) and oxidation product (Fe₃O₄) were successfully loaded and efficiently dispersed on zeolite. The synthesized Zeo-Fe exhibited excellent adsorption and redox capacities for the cations Pb²⁺, Cd²⁺ and anions Cr⁶⁺, As³⁺. The increase in the pH resulting from Fe⁰ corrosion also enhanced the precipitation of Fe-metal(loid)s. The maximum removal capacity for Pb²⁺, Cd²⁺, Cr⁶⁺ and As³⁺ was up to 70.00, 9.12, 2.35 and 0.36 mg/g, respectively. The removal processes were well described by the pseudo-second-order kinetic model for Pb²⁺ and Cd²⁺, Lagergren pseudo first-order kinetics model for As³⁺ and double phase first order kinetics model l for Cr⁶⁺. Cr⁶⁺ was rapidly reduced to Cr³⁺ by the Fe⁰ stabilized on Zeo-Fe, and the oxidation of As³⁺ to As⁵⁺ was attributed to the Fe^0/Fe²⁺ oxidation process at the interface over time, which was further demonstrated by the mineral phase and element valence analyses of reacted Zeo-Fe. The removal mechanism for metal(loid)s was a combination of physical and chemical processes, including adsorption, co-precipitation and reduction-oxidation. Conclusively, Zeo-Fe has been shown to have potential as an effective and economical material for removing various metal(loid)s used in PRB.

Keywords: Metal(loid)s; Mine groundwater; Permeable reactive barrier; Removal mechanism; Zeolite-supported iron.

MeSH terms

Adsorption
Cadmium / analysis
Chromium / chemistry
Groundwater* / chemistry
Iron / chemistry
Lead / analysis
Water Pollutants, Chemical* / analysis
Zeolites* / chemistry

Substances

Water Pollutants, Chemical
Cadmium
Chromium
Zeolites
Lead
Iron