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Fu P, Chen Z, Yang T. Removal of aqueous Cu 2+ ions with Fe 0/C ceramsites fabricated by direct reduction roasting of magnetite, coal, and paper mill sludge. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2018; 78:1753-1761. [PMID: 30500799 DOI: 10.2166/wst.2018.457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The porous metallic iron/carbon (Fe0/C) ceramsites, with virtues of low cost and 'green' fabrication, were prepared by direct reduction roasting of magnetite, coal, and paper mill sludge. The X-ray diffraction data revealed that Fe0 was generated in situ by reducing the magnetite at 1,200 °C. Scanning electron microscopy with energy-dispersive X-ray spectroscopy indicated that Fe0 particles, with a size of <10 μm, were highly dispersed on carbon particles to form an integrated anode (Fe0) and cathode (C) structure of microelectrolysis filters. The effects of initial solution pH and Fe/C mass ratio on Cu2+ removal were investigated. The extent of Cu2+ removal increased from 93.53% to 99.81% as initial pH rose from 2.5 to 7.0. The residual Cu2+ concentration was as low as <0.2 mg/L. The highest extent of Cu2+ removal was achieved at Fe/C mass ratio of 6.8:1. The pseudo-second-order kinetic model fitted well for Cu2+ removal by the ceramsite, revealing the chemisorption as a limiting step. The Cu2+ adsorption equilibrium data were well described by the Langmuir isotherm, with a maximum adsorption capacity of 546.45 mg/g at initial pH 3.0.
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Affiliation(s)
- Pingfeng Fu
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing 100083, China E-mail:
| | - Zihao Chen
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing 100083, China E-mail:
| | - Tianwen Yang
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing 100083, China E-mail:
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Chou YH, Choo KH, Chen SS, Yu JH, Peng CY, Li CW. Copper recovery via polyelectrolyte enhanced ultrafiltration followed by dithionite based chemical reduction: Effects of solution pH and polyelectrolyte type. Sep Purif Technol 2018. [DOI: 10.1016/j.seppur.2017.02.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Ya V, Martin N, Chou YH, Chen YM, Choo KH, Chen SS, Li CW. Electrochemical treatment for simultaneous removal of heavy metals and organics from surface finishing wastewater using sacrificial iron anode. J Taiwan Inst Chem Eng 2018. [DOI: 10.1016/j.jtice.2017.12.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Li CW, Yu JH, Liang YM, Chou YH, Park HJ, Choo KH, Chen SS. Ni removal from aqueous solutions by chemical reduction: Impact of pH and pe in the presence of citrate. JOURNAL OF HAZARDOUS MATERIALS 2016; 320:521-528. [PMID: 27597152 DOI: 10.1016/j.jhazmat.2016.08.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 08/04/2016] [Accepted: 08/10/2016] [Indexed: 06/06/2023]
Abstract
The chemical precipitation of Ni ions from industrial wastewater at alkaline pH values creates waste chemical sludge (e.g., Ni(OH)2). We herein focused on Ni removal via chemical reduction using dithionite, by converting Ni(II) to its elemental or other valuable forms. Without the presence of a chelator (e.g., citrate), the nickel reduction efficiency increased with increasing dithionite:Ni molar ratio, reaching ∼99% at ratios above 3:1. The effect of pH on Ni reduction was in agreement with the standard redox potentials (pe0) of dithionite, which became more negative with an increase in pH leading to greater Ni reduction efficiencies. With the formation of Ni-citrate chelates, however, the Ni reduction deteriorated. Elevated pH and temperature improved nickel reduction, due to the greater reducing power of dithionite. The optimal pH value for Ni(II) reduction was found to be ∼8. Injecting Cu seed particles enhanced the rate and amount of Ni reduced. NiS and Ni3S2 were identified in the crystal of the resulting solids by X-ray crystallography, and the presence of elemental Ni was explained by X-ray photoelectron spectroscopy. The chemical reduction of actual printed circuit board wastewater with the dithionite:Ni(II) molar ratio dose of 12:1 retrieved ∼99% nickel after 30-min reaction at 40°C.
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Affiliation(s)
- Chi-Wang Li
- Department of Water Resources and Environmental Engineering, Tamkang University, No. 151 Yingzhuan Road, Tamsui District, New Taipei City, 25137, Taiwan.
| | - Jui-Hsuan Yu
- Department of Water Resources and Environmental Engineering, Tamkang University, No. 151 Yingzhuan Road, Tamsui District, New Taipei City, 25137, Taiwan; Department of Marine Leisure and Tourism, Taipei College of Maritime Technology, No. 150, Sec. 3, Binhai Road, Tamsui District, New Taipei City, 251, Taiwan
| | - Yang-Min Liang
- Department of Water Resources and Environmental Engineering, Tamkang University, No. 151 Yingzhuan Road, Tamsui District, New Taipei City, 25137, Taiwan
| | - Yi-Hsuan Chou
- Department of Water Resources and Environmental Engineering, Tamkang University, No. 151 Yingzhuan Road, Tamsui District, New Taipei City, 25137, Taiwan
| | - Hyung-June Park
- Department of Environmental Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu, 41566, Republic of Korea
| | - Kwang-Ho Choo
- Department of Environmental Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu, 41566, Republic of Korea.
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Road, Taipei, 106, Taiwan
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