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Zhou Y, Qiu J, Hu S, Liu K, Peng Q, Yi S, Cai Q, Lei X. Study on the efficacy and mechanism of treatment of manganese-containing wastewater by pulse-alternating current coagulation. ENVIRONMENTAL TECHNOLOGY 2024:1-11. [PMID: 38780508 DOI: 10.1080/09593330.2024.2354517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Accepted: 05/02/2024] [Indexed: 05/25/2024]
Abstract
To assess the effectiveness and underlying mechanism of pulse-alternating current coagulation (PACC) for treating manganese-laden wastewater, we examined the influence of various parameters. Specifically, we investigated the impact of current density, initial pH, initial Mn2+ concentration, electrolyte concentration, and alternating current frequency on the removal efficacy. The removal mechanism was meticulously examined using an adsorption kinetics analysis, Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDS), Fourier Transform Infrared Spectrum (FTIR), and X-ray Photoelectron Spectroscopy (XPS). The findings indicated that the concentration of Re(Mn2+) was 99.09% under the specified conditions: j = 2.5 A·m-2, pH0 = 7, c0(Mn2+) = 50 mg·dm-3, f = 500 Hz, c0(NaCl) = 500 mg·dm-3 and t = 40 min. When Re(Mn2+) = 98%, the energy consumption (EEC) was significantly lower for PACC at 1.23 kWh·m-3, compared to 1.52 kWh·m-3 for direct current condensation (DCC). This indicated a reduction in EEC by 19.1% when using PACC over DCC. The adsorption process of Mn2+ by the iron sol adheres to the principles of pseudo-second order kinetics. The primary component of flocs generated in the PACC process is α-FeOOH. The mechanism of Mn2+ removal in the PACC process involved the synthesis of Mn oxides, the formation of metal hydroxide precipitates and adsorption by nano-iron sol. This study provides a theoretical basis and technical support for the application of PACC technology in the field of manganese-containing wastewater treatment.
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Affiliation(s)
- Yihui Zhou
- Hunan Automotive Engineering Vocational College, Zhuzhou, People's Republic of China
- Aerospace Kaitian Environmental Technology Co., Ltd., Changsha, People's Republic of China
| | - Jingxian Qiu
- Aerospace Kaitian Environmental Technology Co., Ltd., Changsha, People's Republic of China
| | - Simeng Hu
- College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha, People's Republic of China
| | - Kang Liu
- College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha, People's Republic of China
| | - Qingjuan Peng
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, People's Republic of China
| | - Shi Yi
- Hunan Automotive Engineering Vocational College, Zhuzhou, People's Republic of China
| | - Qunhuan Cai
- Hu-nan New Frontier Sci & Tech Co, Ltd., Changsha, People's Republic of China
| | - Xiping Lei
- Hunan Automotive Engineering Vocational College, Zhuzhou, People's Republic of China
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Sun M, Liu X, Liu Z. Effective oxidation decomplexation of Cu-EDTA and Cu 2+ electrodeposition from PCB manufacturing wastewater by persulfate-based electrochemical oxidation: Performance and mechanisms. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:30072-30084. [PMID: 38594564 DOI: 10.1007/s11356-024-32955-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 03/13/2024] [Indexed: 04/11/2024]
Abstract
Complex wastewater matrices such as printed circuit board (PCB) manufacturing wastewater present a major environmental concern. In this work, simultaneous decomplexation of metal complex Cu-EDTA and reduction/electrodeposition of Cu2+ was conducted in a persulfate-based electrochemical oxidation system. Oxidizing/reductive species were simultaneously produced in this system, which realized 99.8% of Cu-EDTA decomplexation, 94.5% of Cu2+ reduction/electrodeposition under the conditions of original solution pH = 3.2, electrode distance = 3 cm, [Na2S2O8]0 = 5 mM, current density = 12 mA/cm2, and reaction time = 180 min. The total treatment cost is as low as 0.80 USD/mol Cu-EDTA. Effective mineralization (74.1% total organic carbon removal) of the solution was obtained after 3 h of treatment. •OH and SO4•- drove the Cu-EDTA decomplexation, destroying the chelating sites and finally it was effectively mineralized to CO2, H2O and Cu2+. The mechanisms of copper electrodeposition on the stainless steel cathode and persulfate activation by the BDD anode were proposed based on the electrochemical measurements. The electrodes exhibited excellent reusability and low metal (total iron and Ni2+) leaching during 20 cycles of application. This study provide an effective and sustainable method for the application of the electro-persulfate process in treating complex wastewater matrices.
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Affiliation(s)
- Ming Sun
- School of Civil Engineering and Architecture, East China JiaoTong University, Nanchang, 330013, China
- Jiangxi Provincial Academy of Eco-Environmental Science Research and Planning, Nanchang, 330039, China
| | - Xuemei Liu
- School of Civil Engineering and Architecture, East China JiaoTong University, Nanchang, 330013, China.
| | - Zhanmeng Liu
- School of Civil Engineering and Architecture, Nanchang Institute of Technology, Nanchang, 330099, China
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Zhang Z, Gao C, Chen H, Zhang X, Tan C, Gong Y, Bai X, Zhang Y, Li H. The investigation of sorption-desorption performance and mechanism of copper by surfactant-modified zeolite in aqueous solutions. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:22962-22975. [PMID: 38418787 DOI: 10.1007/s11356-024-32622-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 02/20/2024] [Indexed: 03/02/2024]
Abstract
As the most common filler in stormwater treatment, zeolite (NZ-Y) has good cation exchange capability and stabilization potential for the removal of heavy metal from aqueous solutions. In this study, sodium dodecyl sulfate (SDS) and NZ-Y were selected to preparing new adsorbent (SDS-NZ) by using a simple hydrothermal method. The sorption-desorption performance and mechanism of Cu(II) onto SDS-NZ were investigated. The results showed that the sorption of Cu(II) on SDS-NZ was in accordance with the pseudo-second-order kinetic model with an equilibrium time of 4 h. The sorption behavior fitted Langmuir isotherm with a saturation sorption capability of 9.03 mg/g, which was three times higher than that of NZ-Y. The modification of SDS increases the average pore size of NZ-Y by 3.96 nm, which results in a richer internal pore structure and more useful sorption sites for Cu(II) sorption. There was a positive correlation between solution pH values and sorption capability of Cu(II) in the range of 3.0-6.0. With the ionic strength increased, the sorption capability of Cu(II) onto SDS-NZ first decreased and then increased, which may be attributed to competitive sorption and compression of the electronic layer. The desorption of Cu(II) on SDS-NZ was favored by the increase in SDS concentration and ionic strength and decrease in solution pH values. The application of SDS-NZ in runoff improved the leaching risk of Cu(II). After several cycles, the ability of reused SDS-NZ to efficiently adsorb most heavy metals was verified with removal rates above 99%.
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Affiliation(s)
- Ziyang Zhang
- Beijing Energy Conservation & Sustainable Urban and Rural Development Provincial and Ministry Co-Construction Collaboration Innovation Center, Beijing, 102616, China
| | - Chenyu Gao
- Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control, Beijing University of Civil Engineering and Architecture, Beijing, 102616, China
| | - Hongrui Chen
- CRRC Environmental Science & Technology Cooperation, Beijing, 102616, China
| | - Xiaoran Zhang
- Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control, Beijing University of Civil Engineering and Architecture, Beijing, 102616, China
| | - Chaohong Tan
- Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control, Beijing University of Civil Engineering and Architecture, Beijing, 102616, China
| | - Yongwei Gong
- Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control, Beijing University of Civil Engineering and Architecture, Beijing, 102616, China
| | - Xiaojuan Bai
- Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control, Beijing University of Civil Engineering and Architecture, Beijing, 102616, China
| | - Yanfei Zhang
- Beijing Drainage Group Co, LTD, Beijing, 100044, China
| | - Haiyan Li
- Beijing Energy Conservation & Sustainable Urban and Rural Development Provincial and Ministry Co-Construction Collaboration Innovation Center, Beijing, 102616, China.
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Wang Z, An X, Wang P, Du X, Hao X, Hao X, Ma X. Removal of high concentration of chloride ions by electrocoagulation using aluminium electrode. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:50567-50581. [PMID: 36795207 DOI: 10.1007/s11356-023-25792-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 02/03/2023] [Indexed: 02/17/2023]
Abstract
Wastewater containing a high concentration of chloride ions (Cl- ions) generated in industrial production will corrode equipment and pipelines and cause environmental problems. At present, systematic research on Cl- removal by electrocoagulation is scarce. To study the Cl- removal mechanism, process parameters (current density and plate spacing), and the influence of coexisting ions on the removal of Cl- in electrocoagulation, we use aluminum (Al) as the sacrificial anode, combined with physical characterization and density functional theory (DFT) to study Cl- removal by electrocoagulation. The result showed that the use of electrocoagulation technology to remove Cl- can reduce the concentration of Cl- in an aqueous solution below 250 ppm, meeting the Cl- emission standard. The mechanism of Cl- removal is mainly co-precipitation and electrostatic adsorption by forming chlorine-containing metal hydroxyl complexes. The current density and plate spacing affect the Cl- removal effect and operation cost. As a coexisting cation, magnesium ion (Mg2+) promotes the removal of Cl-, while calcium ion (Ca2+) inhibits it. Fluoride ion (F-), sulfate (SO42-), and nitrate (NO3-) as coexisting anions affect the removal of Cl- ions through competitive reaction. This work provides a theoretical basis for the industrialization of Cl- removal by electrocoagulation.
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Affiliation(s)
- Zirui Wang
- Department of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, 030024, China
| | - Xiaowei An
- Department of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, 030024, China
| | - Peifen Wang
- Department of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, 030024, China
| | - Xiao Du
- Department of Chemical Engineering, Taiyuan University of Technology, Taiyuan, 030024, China
| | - Xiaogang Hao
- Department of Chemical Engineering, Taiyuan University of Technology, Taiyuan, 030024, China
| | - Xiaoqiong Hao
- Department of Petroleum and Chemical Engineering, Jiangsu Key Lab Advanced Catalytic Materials and Technology, Changzhou University, Changzhou, 213164, China
| | - Xuli Ma
- Department of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, 030024, China.
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Zhang W, Zhang M, Yao J, Long J. Industrial indigo dyeing wastewater purification: effective COD removal with Peroxi-AC electrocoagulation system. ARAB J CHEM 2023. [DOI: 10.1016/j.arabjc.2023.104607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
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Abdollahi J, Alavi Moghaddam MR, Habibzadeh S. The role of the current waveform in mitigating passivation and enhancing electrocoagulation performance: A critical review. CHEMOSPHERE 2023; 312:137212. [PMID: 36395897 DOI: 10.1016/j.chemosphere.2022.137212] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 11/07/2022] [Accepted: 11/08/2022] [Indexed: 06/16/2023]
Abstract
Electrocoagulation (EC) can be an efficient alternative to existing water and wastewater treatment methods due to its eco-friendly nature, low footprint, and facile operation. However, the electrodes applied in the EC process suffer from passivation or fouling, an issue resulting from the buildup of poorly conducting materials on the electrode surface. Indeed, such passivation gives rise to various operational problems and restricts the practical implementation of EC on a large scale. Therefore, it has been suggested that using pulsed direct current (PDC), alternating pulse current (APC), and sinusoidal alternating current (AC) waveforms in EC as alternatives to conventional direct current (DC) can help mitigate passivation and alleviate its associated detrimental effects. This paper presents a critical review of the impact of the current waveform on the EC process towards the capabilities of the PDC, APC, and AC waveforms in de-passivation and performance enhancement while comparing them to the conventional DC. Additionally, current waveform parameters influencing the surface passivation of electrodes and process efficiency are elaborately discussed. Meanwhile, the performance of the EC process is evaluated under different current waveforms based on pollutant removal efficiency, energy consumption, electrode usage, sludge production, and operating cost. The proper current waveforms for treating various water and wastewater matrices are also explained. Finally, concluding remarks and outlooks for future research are provided.
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Affiliation(s)
- Javad Abdollahi
- Department of Civil & Environmental Engineering, Amirkabir University of Technology (Tehran Polytechnic), Iran
| | | | - Sajjad Habibzadeh
- Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Iran
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Zhou Y, Chen S, Qiu J, Zhu C, Xu T, Zeng M, He X, Hu B, Zhang X, Yu G. Removal of phosphorus in wastewater by sinusoidal alternating current coagulation: performance and mechanism. ENVIRONMENTAL TECHNOLOGY 2022; 43:3161-3174. [PMID: 33843473 DOI: 10.1080/09593330.2021.1916093] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 04/02/2021] [Indexed: 06/12/2023]
Abstract
The effects of initial total phosphorus (TP) concentration, current density, conductivity and initial pH value on the removal rate of TP and energy consumption, as well as the behaviour and mechanism of phosphorus removal, were investigated by sinusoidal alternating current coagulation (SACC). The flocs produced by SACC were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy FTIR and X-ray photo electron spectroscopy. The thermodynamic and kinetic behaviours of phosphorus removal by iron sol adsorption were also studied in detail. In a self-made SACC reactor equipped with five sets of parallel iron electrodes spacing 10 mm, the removal rate of TP reached 90.9% for a pH 7.0 wastewater with 5 mg dm-3 TP (κ = 800 μS cm-1) after being treated for 60 min by applying 2.12 mA cm-2 sinusoidal alternating current. Compared with direct current coagulation (DCC), SACC exhibits a higher removal efficiency of phosphorus due to the stronger adsorption of the produced flocs. It was found that the adsorption in the SACC process follows pseudo-second-order kinetic with the involvement of the intra-particle model. The adsorption of iron sol to phosphorus was an endothermic and spontaneous process, and its adsorption behaviour can be characterized with Langmuir and Redlich-Peterson isothermal adsorption models. SACC may be employed for the treatment of more complex wastewater combined with biological and/or electrochemical techniques.
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Affiliation(s)
- Yihui Zhou
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, People's Republic of China
| | - Shuaiqi Chen
- Aerospace Kaitian Environmental Technology Co., Ltd, Changsha, People's Republic of China
| | - Jingxian Qiu
- Aerospace Kaitian Environmental Technology Co., Ltd, Changsha, People's Republic of China
| | - Chunyou Zhu
- Aerospace Kaitian Environmental Technology Co., Ltd, Changsha, People's Republic of China
| | - Tao Xu
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, People's Republic of China
| | - Muping Zeng
- Aerospace Kaitian Environmental Technology Co., Ltd, Changsha, People's Republic of China
| | - Xi He
- Aerospace Kaitian Environmental Technology Co., Ltd, Changsha, People's Republic of China
| | - Bonian Hu
- Department of Materials and Chemical Engineering, Hunan Institute of Technology, Hengyang, People's Republic of China
| | - Xueyuan Zhang
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, People's Republic of China
| | - Gang Yu
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, People's Republic of China
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8
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Investigation on Mechanism of Tetracycline Removal from Wastewater by Sinusoidal Alternating Electro-Fenton Technique. SUSTAINABILITY 2022. [DOI: 10.3390/su14042328] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Sinusoidal alternating electro-Fenton (SAEF) is a new type of advanced electrochemical oxidation technology for the treatment of refractory organic wastewater. In this research, the removal performance and degradation mechanism of tetracycline (TC) were investigated, and the optimal operation parameters were determined. Scanning electron microscope (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectrometer (FTIR) were used to characterize the morphology, elemental composition, crystal structure, function groups of sludge produced by SAEF. UV-visible spectroscopy (UV) and liquid chromatograph-mass spectrometer (LC-MS/MS) were employed to determine the concentration of organic matter, middle products of decomposed organics in the SAEF process, respectively. The results showed that the removal rates of TC, chemical oxygen demand (COD), electric energy consumption (EEC) and the amount of produced sludge (Ws) are 94.87%, 82.42%, 1.383 kWh⋅m−3 and 0.1833 kg⋅m−3 by SAEF, respectively, under the optimal conditions (pH = 3.0, conductivity (κ) = 1075 μS⋅cm−1, current density (j) = 0.694 mA⋅cm−2, initial c (TC) = 100 mg·dm−3, c [30%H2O2] = 1.17 cm3⋅dm−3, frequency (f) = 50 Hz, t = 120 min). Compared with pure direct electro-Fenton (DEF) or sinusoidal alternating current coagulation (SACC), SAEF was a highly effective method with low-cost for the treatment of TC wastewater. It was found that the conjugated structure of TC was destroyed to generate intermediate products, and then most of them was gradually mineralized into inorganic materials in the SAEF process.
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Xu T, Zheng X, Zhou Y, Zhu C, Hu B, Lei X, Zhang X, Yu G. Study on the treatment of Cu 2+-organic compound wastewater by electro-Fenton coupled pulsed AC coagulation. CHEMOSPHERE 2021; 280:130679. [PMID: 34162078 DOI: 10.1016/j.chemosphere.2021.130679] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 03/23/2021] [Accepted: 04/22/2021] [Indexed: 06/13/2023]
Abstract
Electro-Fenton (EF) coupled with Pulsed alternating current coagulation (PACC) is an effective technology for the treatment of Cu2+-organic wastewater. In this study, the removal efficiency (Re), electrical energy consumption (EEC) and removal mechanism of Cu2+-organic were analyzed and the optimal operation parameters were determined. SEM, EDS, XRD and FTIR were used to characterize the morphology, elemental composition, crystal structure, function groups of sludge produced in the EF-PACC. UV, ESR and GC-MS were employed to determine concentration of organic matter, existence of OH, middle products of decomposed organic matter in EF-PACC, respectively. The results show that under the optimal conditions of initial pH = 2.5, current density (j) = 2 A/m2, initial c(Cu2+) = 50 mg/L, c(chemical oxygen demand, COD) = 500 mg/L, c[H2O2] = 10 mL/L, frequency (f) = 1 Hz, t = 20 min, the Re(Cu2+) can reach 99.59%. Re(COD) is 90.21%, EEC 1.695 × 10-1 kWh/m3, and the amount of produced sludge (Ws) is 0.9283 kg/m3. Compared with single EF and PACC processes, the order of treatment efficiency is EF-PACC > EF > PACC. EF-PACC technique was a highly effective method in the treatment of Cu2+-organic compound wastewater. The EF-PACC coupled process includes that electrolyzed Fe3+ produces electrocoagulation and OH produces degradation of organic compounds. The combined action of the two effects can effectively remove Cu2+-organic from wastewater.
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Affiliation(s)
- Tao Xu
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Xiaotong Zheng
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Yihui Zhou
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Chunyou Zhu
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Bonian Hu
- Department of Materials and Chemical Engineering, Hunan Institute of Technology, Hengyang, 421008, China.
| | - Xiping Lei
- Hunan Zihong Ecology Technology Co., Ltd, Changsha, 410000, China
| | - Xueyuan Zhang
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Gang Yu
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China.
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Wang R, Shu J, Chen M, Wang R, He D, Wang J, Tang C, Han Y, Luo Z. An innovative method for fractionally removing high concentrations of Ni2+, PO43−, TP, COD, and NH4+-N from printed-circuit-board nickel plating wastewater. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2020.118241] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Zhou Y, Xu T, Ou J, Zou G, Lei X, Hu B, Yu G. Treatment of Zn 2+ in wastewater by sinusoidal alternating current coagulation: response surface methodology and removal mechanism. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2020; 82:1950-1960. [PMID: 33201857 DOI: 10.2166/wst.2020.466] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
A novel sinusoidal alternating current coagulation (SACC) technique was used to remove the Zn2+ from wastewater in the present study. The response surface methodology was used to analyze the effect of current density, time, initial pH and initial Zn2+ concentration in order to obtain the optimum removal efficiency and to lower energy consumption. The results show that SACC with a current density of 0.31 A·m-2 applied to treat wastewater containing 120 mg·dm-3 Zn2+ at pH = 9 for 21.3 min can achieve a removal efficiency of Zn2+ of 98.80%, and the energy consumption is 1.147 kWh·m-3. The main component of flocs produced in SACC process is Fe5O7OH·4H2O (HFO). Large specific surface area and good adsorption performance of HFO are demonstrated. There is strong interaction between Zn2+ and HFO. Zn2+ is adsorbed and trapped by HFO and then co-precipitated. Freundlich adsorption isotherm model and pseudo-second order kinetics model explained the Zn2+ adsorption behavior well. The Zn2+ adsorption on HFO is an endothermic and spontaneous process.
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Affiliation(s)
- Yihui Zhou
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China E-mail: ; Joint first authors
| | - Tao Xu
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China E-mail: ; Joint first authors
| | - Jinhua Ou
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China E-mail: ; Department of Materials and Chemical Engineering, Hunan Institute of Technology, Hengyang 421008, China
| | - Gege Zou
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China E-mail:
| | - Xiping Lei
- Hunan Zihong Ecology Technology Co., Ltd, Changsha 410082, China
| | - Bonian Hu
- Department of Materials and Chemical Engineering, Hunan Institute of Technology, Hengyang 421008, China
| | - Gang Yu
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China E-mail:
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