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Wu H, Shi Z, Sun B, Zheng B, Shah KJ, Lin S. Defluoridation by positive single-pulse current electrocoagulation from photovoltaic wastewater: Energy consumption assessment and mechanism analysis. CHEMOSPHERE 2024; 363:142773. [PMID: 38972457 DOI: 10.1016/j.chemosphere.2024.142773] [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: 04/16/2024] [Revised: 06/30/2024] [Accepted: 07/03/2024] [Indexed: 07/09/2024]
Abstract
The presence of fluoride ions (F-) in photovoltaic (PV) wastewater significantly affects the integrity of the ecological environment. In contrast to direct current electrocoagulation (DC-EC), positive single-pulse electrocoagulation (PSPC-EC) shows a significant reduction in both the formation of passivation films on electrodes and the consumption of electrical energy. Under the experimental conditions of an Al-Al-Al-Al electrode combination, an electrode spacing of 1.0 cm, a NaCl concentration of 0.05 mol L-1, an initial pH of 5.6, an initial F- concentration of 5 mg L-1, a current density of 5 A m-2, a pulse frequency of 500 Hz, and a 40 % duty cycle, the achieved equilibrium F- removal efficiencies were 84.0 % for DC-EC and 88.0 % for PSPC-EC, respectively, accompanied by power consumption of 0.0198 kWh·mg-1 and 0.0073 kWh·mg-1. The flocs produced in the PSPC-EC process were characterized using scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy and it is revealed that the F- removal mechanisms in the PSPC-EC process include co-precipitation, hydrogen bond complexation, and ion exchange. When the actual PV wastewater was finally subjected to treatment under the optimal PSPC-EC conditions, the F- concentration in the wastewater was reduced from 4.6 mg L-1 to 1.4 mg L-1. This paper provides both a theoretical framework and a technological basis for the application of PSPC-EC in the advanced treatment of PV wastewater.
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Affiliation(s)
- Haixia Wu
- College of Urban Construction, Nanjing Tech University, Nanjing, 211816, China.
| | - Zhiru Shi
- College of Urban Construction, Nanjing Tech University, Nanjing, 211816, China
| | - Bingyuan Sun
- College of Urban Construction, Nanjing Tech University, Nanjing, 211816, China
| | - Bin Zheng
- College of Urban Construction, Nanjing Tech University, Nanjing, 211816, China
| | - Kinjal J Shah
- College of Urban Construction, Nanjing Tech University, Nanjing, 211816, China.
| | - Shaohua Lin
- School of Civil Engineering, Nanjing Forestry University, Nanjing, 210037, China
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2
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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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3
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Momin ZH, Lingamdinne LP, Kulkarni R, Pal CA, Choi YL, Chang YY, Koduru JR. Exploring recyclable alginate-enhanced GCN-LDO sponge for U(VI) and Cd(II) removal: Insights from batch and column studies. JOURNAL OF HAZARDOUS MATERIALS 2024; 469:134015. [PMID: 38518691 DOI: 10.1016/j.jhazmat.2024.134015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 03/01/2024] [Accepted: 03/11/2024] [Indexed: 03/24/2024]
Abstract
Developing effective water treatment materials, particularly through proven adsorption methods, is crucial for removing heavy metal contaminants. This study synthesizes a cost-effective three-dimensional material encapsulating graphitic carbon nitride-layered double oxide (GCN-LDO) in sodium alginate (SA) through the freeze-drying method. The material is applied to remove uranium (U(VI)) and cadmium (Cd(II)) in real water systems. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) analyses conclusively verified the elemental composition and successful encapsulation of GCN-LDO within the SA matrix. Removal effectiveness was tested under various conditions, including adsorbent dose, ionic strength, contact time, temperature, different initial pollutant concentrations, and the impact of co-existing ions. The adsorption of U(VI) and Cd(II) conformed to the pseudo-second-order (PSO) kinetic model, signifying a chemical interaction between the sodium alginate-graphitic carbon nitride-layered double oxide (SA-GCN-LDO) sponge and the metal ions. The Langmuir isotherm indicated monolayer, homogeneous adsorption for U(VI) and Cd(II) with capacities of 158.25 and 165.00 mg/g. SA-GCN-LDO recyclability was found in up to seven adsorption cycles with a removal efficacy of 70%. The temperature effect study depicts the exothermic nature of the U(VI) and Cd(II) ion removal process. Various mechanisms involved in U(VI) and Cd(II) removal were proposed. Further, continuous fixed bed column studies were performed, and Thomas and the Yoon-Nelson model were studied. These insights from this investigation contribute to advancing our knowledge of the material's performance within the context of U(VI) and Cd(II) adsorption, paving the way for optimized and sustainable water treatment solutions.
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Affiliation(s)
- Zahid Husain Momin
- Department of Environmental Engineering, Kwangwoon University, Seoul 139-701, Republic of Korea
| | | | - Rakesh Kulkarni
- Department of Environmental Engineering, Kwangwoon University, Seoul 139-701, Republic of Korea
| | | | - Yu-Lim Choi
- Department of Environmental Engineering, Kwangwoon University, Seoul 139-701, Republic of Korea
| | - Yoon-Young Chang
- Department of Environmental Engineering, Kwangwoon University, Seoul 139-701, Republic of Korea
| | - Janardhan Reddy Koduru
- Department of Environmental Engineering, Kwangwoon University, Seoul 139-701, Republic of Korea.
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4
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Li Q, You Y, Hu X, Lu D, Wen Q, Yu G, Wang W, Xu T. Preparation of amino-modified carbon quantum dots-ZnO/cellulose nanofiber multifunctional hydrogel: Enhanced adsorption synergistic photoreduction and reversible fluorescence response visual recognition of Cr(VI). Int J Biol Macromol 2024; 254:128068. [PMID: 37967594 DOI: 10.1016/j.ijbiomac.2023.128068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 11/03/2023] [Accepted: 11/10/2023] [Indexed: 11/17/2023]
Abstract
This work innovatively used cellulose nanofibers as a photocatalyst carrier, which could recycle nano-photocatalysts and minimize nanoparticle aggregation. The morphology, structures, chemical composition, optical-electronic properties and photocatalytic performance of amino-modified carbon quantum dots-ZnO/cellulose nanofiber (N-CQDs-ZnO/CNF: ZCH-2) hydrogel were characterized by SEM, TEM, BET, EDS, XRD, FTIR, UV-vis, XPS, PL and other techniques. The mechanism of Cr(VI) adsorption synergistic photoreduction by ZCH-2 was discussed in detail. The results showed that the prepared ZCH-2 had excellent removal performance for Cr(VI). After 120 min of adsorption and 40 min of photoreduction, the removal efficiency of Cr(VI) was 98.9 %. Compared with ZnO/CNF hydrogel, the adsorption performance of ZCH-2 increased by 268 % and the photoreduction performance increased by 116 %. The adsorption of Cr(VI) by ZCH-2 was controlled by electrostatic attraction and chemical adsorption. The photoreduction kinetic constant of ZCH-2 was 0.106 min-1, which was 8.9 times that of ZnO/CNF hydrogel. The N-CQDs in ZCH-2 could form N-CQDs-metal complexes with Cr(VI), resulting in fluorescence quenching, so Cr(VI) could be visually identified by fluorescence changes. This study provides a new idea for the design and optimization of a new multifunctional hydrogel with efficient adsorption-photoreduction-fluorescence recognition.
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Affiliation(s)
- Qing Li
- College of Science, Central South University of Forestry and Technology, Changsha 410004, China
| | - Yong You
- College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Xingyu Hu
- College of Science, Central South University of Forestry and Technology, Changsha 410004, China
| | - Danqing Lu
- College of Science, Central South University of Forestry and Technology, Changsha 410004, China
| | - Qian Wen
- College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Gang Yu
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Wenlei Wang
- College of Science, Central South University of Forestry and Technology, Changsha 410004, China
| | - Tao Xu
- College of Science, Central South University of Forestry and Technology, Changsha 410004, China.
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5
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Zannotti M, Rossi A, Minicucci M, Ferraro S, Petetta L, Giovannetti R. Water Decontamination from Cr(VI) by Transparent Silica Xerogel Monolith. Int J Mol Sci 2023; 24:ijms24087430. [PMID: 37108592 PMCID: PMC10138445 DOI: 10.3390/ijms24087430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 04/12/2023] [Accepted: 04/16/2023] [Indexed: 04/29/2023] Open
Abstract
Cr(VI) is highly soluble and mobile in water solution and extremely toxic. In order to obtain a specific material with adsorption properties towards Cr(VI), and that can be used in environmental remediation of water contaminated with Cr(VI), one-step sol-gel technique, at low temperature (50 °C), has been optimized to prepare transparent silica-based xerogel monolith by using tetraethyl orthosilicate as precursor. The obtained xerogel, with disk shape, was fully characterized by Raman, BET, FE-SEM and XRD analysis. The results indicated that the material showed silica amorphous phase and high porosity. The study of the adsorption properties towards different concentrations of Cr(VI), in the form of HCrO4- in acidic condition, showed prominent results. The absorption kinetics were evaluated by studying different models, the final result showing that the absorption of Cr(VI) occurred through intra-particle diffusion process, following two steps, and that the absorption equilibrium is regulated by Freundlich isotherm model. The material can be restored by reducing the hazardous Cr(VI) to Cr(III), a less toxic form of chromium, by 1,5-diphenylcarbazide, and with successive treatment in acidic water.
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Affiliation(s)
- Marco Zannotti
- Chemistry Interdisciplinary Project, School of Science and Technology, Chemistry Division, University of Camerino, 62032 Camerino, Italy
| | - Andrea Rossi
- Chemistry Interdisciplinary Project, School of Science and Technology, Chemistry Division, University of Camerino, 62032 Camerino, Italy
| | - Marco Minicucci
- School of Science and Technology, Physics Division, University of Camerino, 62032 Camerino, Italy
| | - Stefano Ferraro
- Chemistry Interdisciplinary Project, School of Science and Technology, Chemistry Division, University of Camerino, 62032 Camerino, Italy
| | - Laura Petetta
- Chemistry Interdisciplinary Project, School of Science and Technology, Chemistry Division, University of Camerino, 62032 Camerino, Italy
| | - Rita Giovannetti
- Chemistry Interdisciplinary Project, School of Science and Technology, Chemistry Division, University of Camerino, 62032 Camerino, Italy
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6
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Lü X, Xu T, Zhou Y, Peng Q, Ou J, Hu B, Xie Z, Lei X, Yu G. Effect of iron ion configurations on Ni 2+ removal in electrocoagulation. J Environ Sci (China) 2023; 124:823-834. [PMID: 36182186 DOI: 10.1016/j.jes.2022.01.037] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 01/21/2022] [Accepted: 01/21/2022] [Indexed: 06/16/2023]
Abstract
Electrocoagulation (EC) has been widely used to treat the heavy metal wastewater in industry. A novel process of sinusoidal alternating current electrocoagulation (SACC) is adopted to remove Ni2+ in wastewater in this study. The morphology of precipitates and the distribution of the main functional iron configurations were investigated. Ferron timed complex spectroscopy can identify the monomeric iron configurations [Fe(a)], oligomeric iron configurations [Fe(b)] and polymeric iron configurations [Fe(c)]. The optimal operating conditions of SACC process were determined through single-factor experiments. The maximum Ni2+ removal efficiency [Re(Ni2+)] was achieved under the conditions of pH0=7, current density (j) = 7 A/m2, electrolysis time (t) = 25 min, c0(Ni2+) = 100 mg/L. At pH=7, the proportion of Fe(b) and Fe(c) in the system was 50.4 at.% and 23.1 at.%, respectively. In the SACC process, Fe(b) and Fe(c) are the main iron configurations in solution, while Fe(c) are the vast majority of the iron configurations in the direct current electrocoagulation (DCC) process. Re(Ni2+) is 99.56% for SACC and 98.75% for DCC under the same optimum conditions, respectively. The precipitates produced by SACC have a high proportion of Fe(b) configurations with spherical α-FeOOH and γ-FeOOH structures which contain abundant hydroxyl groups. Moreover, it is demonstrated that Fe(b) has better adsorption capacity than Fe(c) through adsorption experiments of methyl orange (MO) dye. Fe(a) configurations in the homogeneous solution had no effect on the removal of nickel.
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Affiliation(s)
- Xiaoliu Lü
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Tao Xu
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Yihui Zhou
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Qingjuan Peng
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Jinhua Ou
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China; Research Institute of New Building Materials, Hunan Institute of Technology, Hengyang 421008, China
| | - Bonian Hu
- Research Institute of New Building Materials, Hunan Institute of Technology, Hengyang 421008, China.
| | - Zhihui Xie
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637002, China.
| | - Xiping Lei
- Hunan Zihong Ecology Technology Co., Ltd., Changsha 410000, China
| | - Gang Yu
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China.
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7
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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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8
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Zr4+ cross-linked chitosan-thiourea composite for efficient detoxification of Cr(VI) ions in aqueous solution. Carbohydr Polym 2022; 296:119872. [DOI: 10.1016/j.carbpol.2022.119872] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 07/01/2022] [Accepted: 07/12/2022] [Indexed: 01/04/2023]
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9
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Wang LX, Dao LP, Guo QY, Chen TL, Fu LJ, Zhou FC, Yuan Y. Investigation on the influence of AC electric filed and KCl on the structure and gel properties of Konjac glucomannan. Food Chem 2022; 386:132755. [PMID: 35509158 DOI: 10.1016/j.foodchem.2022.132755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 03/04/2022] [Accepted: 03/19/2022] [Indexed: 11/04/2022]
Abstract
The influence of alternating current (AC) electric field and KCl on the structure and gel properties of Konjac Glucomannan (KGM) were studied in this work by high-performance gel permeation chromatography (HPGPC), acid-base titration, solid-state nuclear magnetic resonance (NMR), X-ray diffraction (XRD), simultaneous differential scanning calorimetry/thermo gravimetric analyzer (DSC/TGA) and a rheometer. HPGPC showed KGM was degraded by AC electric field and Acid-base titration showed that under the action of AC electric field and KCl KGM removed part of acetyl groups, which were consistent with the analysis of NMR. XRD and temperature sweep measurements respectively showed that the electrotreatment time and KCl concentration had important effects on the gel formation and its three-dimensional network. Simultaneous DSC/TGA and temperature sweep measurements both demonstrated the gel had good thermal stability.
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Affiliation(s)
- Li-Xia Wang
- School of Environmental and Biological Engineering, Fujian Provincial Key Laboratory of Ecology- Toxicological Effects & Control for Emerging Contaminants, Key Laboratory of Loquat Germplasm Innovation and Utilization, Putian University, Putian 351100, China
| | - Li-Ping Dao
- School of Environmental and Biological Engineering, Fujian Provincial Key Laboratory of Ecology- Toxicological Effects & Control for Emerging Contaminants, Key Laboratory of Loquat Germplasm Innovation and Utilization, Putian University, Putian 351100, China; College of Food Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Qi-Yong Guo
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China
| | - Tian-Long Chen
- School of Environmental and Biological Engineering, Fujian Provincial Key Laboratory of Ecology- Toxicological Effects & Control for Emerging Contaminants, Key Laboratory of Loquat Germplasm Innovation and Utilization, Putian University, Putian 351100, China
| | - Li-Jun Fu
- School of Environmental and Biological Engineering, Fujian Provincial Key Laboratory of Ecology- Toxicological Effects & Control for Emerging Contaminants, Key Laboratory of Loquat Germplasm Innovation and Utilization, Putian University, Putian 351100, China.
| | - Feng-Chao Zhou
- School of Environmental and Biological Engineering, Fujian Provincial Key Laboratory of Ecology- Toxicological Effects & Control for Emerging Contaminants, Key Laboratory of Loquat Germplasm Innovation and Utilization, Putian University, Putian 351100, China
| | - Yi Yuan
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China.
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10
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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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11
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Pachaiappan R, Cornejo-Ponce L, Rajendran R, Manavalan K, Femilaa Rajan V, Awad F. A review on biofiltration techniques: Recent advancements in the removal of volatile organic compounds and heavy metals in the treatment of polluted water. Bioengineered 2022; 13:8432-8477. [PMID: 35260028 PMCID: PMC9161908 DOI: 10.1080/21655979.2022.2050538] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Good quality of water determines the healthy life of living beings on this earth. The cleanliness of water was interrupted by the pollutants emerging out of several human activities. Industrialization, urbanization, heavy population, and improper disposal of wastes are found to be the major reasons for the contamination of water. Globally, the inclusion of volatile organic compounds (VOCs) and heavy metals released by manufacturing industries, pharmaceuticals, and petrochemical processes have created environmental issues. The toxic nature of these pollutants has led researchers, scientists, and industries to exhibit concern towards the complete eradication of them. In this scenario, the development of wastewater treatment methodologies at low cost and in an eco-friendly way had gained importance at the international level. Recently, bio-based technologies were considered for environmental remedies. Biofiltration based works have shown a significant result for the removal of volatile organic compounds and heavy metals in the treatment of wastewater. This was done with several biological sources such as bacteria, fungi, algae, plants, yeasts, etc. The biofiltration technique is cost-effective, simple, biocompatible, sustainable, and eco-friendly compared to conventional techniques. This review article provides deep insight into biofiltration technologies engaged in the removal of volatile organic compounds and heavy metals in the wastewater treatment process.
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Affiliation(s)
- Rekha Pachaiappan
- Departamento de Ingeniería Mecánica, Facultad de Ingeniería, Universidad de Tarapacá, Avda.General Velasquez, 1775, Arica, Chile
| | - Lorena Cornejo-Ponce
- Departamento de Ingeniería Mecánica, Facultad de Ingeniería, Universidad de Tarapacá, Avda.General Velasquez, 1775, Arica, Chile
| | - Rathika Rajendran
- Department of Physics, A.D.M. College for Women (Autonomous), Nagapattinam, Tamil Nadu - 611001, India
| | - Kovendhan Manavalan
- Department of Physics and Nanotechnology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu - 603203, India
| | - Vincent Femilaa Rajan
- Department of Sustainable Energy Management, Stella Maris College (Autonomous), Chennai - 600086, Tamil Nadu, India
| | - Fathi Awad
- Department of Allied Health Professionals, Faculty of Medical and Health Sciences, Liwa College of Technology, Abu Dhabi, UAE
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12
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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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Ou J, Luo K, Tan H, Li N, Hu B, Yu G. Fe 3O 4@N-doped carbon derived from dye wastewater flocculates as a heterogeneous catalyst for degradation of methylene blue. NEW J CHEM 2022. [DOI: 10.1039/d2nj02905g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The study used wastewater to mitigate pollution, wherein the catalyst was derived from MG dye wastewater flocculates produced by electrocoagulation.
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Affiliation(s)
- Jinhua Ou
- School of Materials Science and Engineering, Hunan Institute of Technology, Hengyang, 421002, China
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Kejun Luo
- Changsha Research Institute of Mining and Metallurgy Co., Ltd, Changsha, 410012, China
| | - Hong Tan
- School of Materials Science and Engineering, Hunan Institute of Technology, Hengyang, 421002, China
| | - Ni Li
- School of Materials Science and Engineering, Hunan Institute of Technology, Hengyang, 421002, China
| | - Bonian Hu
- School of Materials Science and Engineering, Hunan Institute of Technology, Hengyang, 421002, China
| | - Gang Yu
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
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Zhou L, Liu L, Qiao W, Gao Y, Zhao Z, Liu D, Bian Z, Wang J, Wang ZL. Improving Degradation Efficiency of Organic Pollutants through a Self-Powered Alternating Current Electrocoagulation System. ACS NANO 2021; 15:19684-19691. [PMID: 34860004 DOI: 10.1021/acsnano.1c06988] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Although electrocoagulation technology has been widely researched in wastewater treatment, high energy consumption and electrode passivation are still the main challenges for its widespread applications. Here, we propose a self-powered electrocoagulation system based on a triboelectric nanogenerator (TENG) with alternating current (AC) outputs to solve these two issues, and thus enhance the removal efficiency of organic pollutants. Compared with the direct current source, the AC power source can reduce the electrode passivation, produce more aluminum hydroxide compounds after consuming an equal amount of charges, and thus improve the degradation efficiency. Moreover, the removal efficiency can be further enhanced by decreasing the frequency AC, in which a 5.7-fold improvement was achieved at 0.2 Hz compared to DC at 1.8 Hz. Inspired by the low frequency of ocean wave water, we developed a self-powered AC-electrocoagulation system to directly drive the electrocoagulation reaction by harvesting water wave energy, which can effectively remove 94.8% of xylenol orange and 98.8% of water-oil emulsion, and thus completely address the problem of energy consumption. This study further promotes the application of self-powered electrochemical systems in treating environmental pollution.
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Affiliation(s)
- Linglin Zhou
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Li Liu
- Education Ministry Key and International Joint Lab of Resource Chemistry and Shanghai Key Lab of Rare Earth Functional Materials, Shanghai Normal University, Shanghai, 200234, China
| | - Wenyan Qiao
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yikui Gao
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhihao Zhao
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Di Liu
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhenfeng Bian
- Education Ministry Key and International Joint Lab of Resource Chemistry and Shanghai Key Lab of Rare Earth Functional Materials, Shanghai Normal University, Shanghai, 200234, China
| | - Jie Wang
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhong Lin Wang
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, China
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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Lu J, Zhang P, Li J. Electrocoagulation technology for water purification: An update review on reactor design and some newly concerned pollutants removal. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 296:113259. [PMID: 34256295 DOI: 10.1016/j.jenvman.2021.113259] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 06/30/2021] [Accepted: 07/08/2021] [Indexed: 06/13/2023]
Abstract
Water shortage and quality deterioration are plaguing people all over the world. Providing sustainable and affordable treatment solutions to these problems is a need of the hour. Electrocoagulation (EC) technology is a burgeoning alternative for effective water treatment, which offers the virtues such as compact equipment, easy operation, and low sludge production. Compared to other water purification technologies, EC shows excellent removal efficacy for a wide range of contaminants in water and has great potential for addressing limitations of conventional water purification technologies. This review summarizes the latest development of principle, characteristics, and reactor design of EC. The design of key parameters including reactor shape, power supply type, current density, as well as electrode configuration is further elaborated. In particular, typical water treatment systems powered by renewable energy (solar photovoltaic and wind turbine systems) are proposed. Further, this review provides an overview on expanded application of EC in the removal of some newly concerned pollutants in recent years, including arsenite, perfluorinated compounds, pharmaceuticals, oil, bacteria, and viruses. The removal efficiency and mechanisms of these pollutants are also discussed. Finally, future research trend and focus are further recommended. This review can bridge the large knowledge gap for the EC application that is beneficial for environmental researchers and engineers.
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Affiliation(s)
- Jianbo Lu
- School of Civil Engineering, Yantai University, Yantai, Shandong, 264005, China.
| | - Peng Zhang
- School of Civil Engineering, Yantai University, Yantai, Shandong, 264005, China
| | - Jie Li
- School of Economics and Management, Yantai University, Yantai, Shandong, 264005, China
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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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Fabrication of nickel-iron layered double hydroxides using nickel plating wastewater via electrocoagulation, and its use for efficient dye removal. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116246] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Decoration of serpentine with iron ore as an efficient low-cost magnetic adsorbent for Cr (VI) removal from tannery wastewater. POWDER TECHNOL 2021. [DOI: 10.1016/j.powtec.2021.04.061] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Liu L, Zhou L, Liu D, Yuan W, Chen S, Li H, Bian Z, Wang J, Wang ZL. Improved Degradation Efficiency of Levofloxacin by a Self-Powered Electrochemical System with Pulsed Direct-Current. ACS NANO 2021; 15:5478-5485. [PMID: 33599489 DOI: 10.1021/acsnano.1c00233] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
With the excellent structural design, rotary triboelectric nanogenerator (R-TENG) is suitable for harvesting mechanical energy such as wind energy and water energy to build a self-powered electrochemical system for environmental science. The electrochemical performance has been greatly improved by using the pulsed direct-current (PDC) output of a TENG; however, a full-wave PDC (FW-PDC) is hardly realized in R-TENG devices due to existence of phase superposition. Here, a R-TENG with FW-PDC output is reported to perform a self-powered electro-Fenton system for enhancing the removal efficiency of levofloxacin (OFL). By adjusting the rotation center angle ratio between each rotator and stator unit, the phase superposition of R-TENG caused by multiple parallel electrodes can be effectively eliminated, thus achieving the desired FW-PDC output. Because of the reduced electrode passivation effect, the removal efficiency of OFL is improved by 30% under equal electric charges through using the designed R-TENG with FW-PDC output compared to traditional R-TENG. This study provides a promising methodology to improve the performance of self-powered electrochemical process for treating environment pollutions.
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Affiliation(s)
- Li Liu
- Education Ministry Key and International Joint Lab of Resource Chemistry and Shanghai Key Lab of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234, China
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083, China
- College of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Linglin Zhou
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083, China
- College of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Di Liu
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083, China
- College of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Yuan
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083, China
- College of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shengyang Chen
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083, China
- College of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hexing Li
- Education Ministry Key and International Joint Lab of Resource Chemistry and Shanghai Key Lab of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234, China
| | - Zhenfeng Bian
- Education Ministry Key and International Joint Lab of Resource Chemistry and Shanghai Key Lab of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234, China
| | - Jie Wang
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083, China
- College of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhong Lin Wang
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083, China
- College of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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Shang Y, Zhu G, Yan D, Liu Q, Gao T, Zhou G. Tannin cross-linked polyethyleneimine for highly efficient removal of hexavalent chromium. J Taiwan Inst Chem Eng 2021. [DOI: 10.1016/j.jtice.2021.02.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Ingelsson M, Yasri N, Roberts EPL. Electrode passivation, faradaic efficiency, and performance enhancement strategies in electrocoagulation-a review. WATER RESEARCH 2020; 187:116433. [PMID: 33002774 DOI: 10.1016/j.watres.2020.116433] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/30/2020] [Accepted: 09/15/2020] [Indexed: 06/11/2023]
Abstract
Treating water and wastewater is energy-intensive, and traditional methods that require large amounts of chemicals are often still used. Electrocoagulation (EC), an electrochemical treatment technology, has been proposed as a more economically and environmentally sustainable alternative. In EC, sacrificial metal electrodes are used to produce coagulant in-situ, which offers many benefits over conventional chemical coagulation. However, material precipitation on the electrodes during long term operation induces a passivating effect that decreases treatment performance and increases power requirements. Overcoming this problem is considered to be the greatest challenge facing the development of EC. In this critical review, the studies that have examined the nature of electrode passivation, and its effect on treatment performance are considered. A fundamental approach is used to examine the association between passivation and faradaic efficiency, a surrogate for EC performance. In addition, the strategies that have been proposed to remove or avoid passivation are reviewed, including aggressive ion addition, AC current operation, polarity reversal, ultrasonication, and mechanical cleaning of the electrodes. It is concluded that the success of implementing each method is dependent on critical operating parameters, and careful consideration should be taken when designing an EC system based on the phenomena discussed in this article. In conclusion, this review provides insight into passivation mechanisms, delivers guidelines for sustaining high treatment performance, and offers an outlook for the future development of EC.
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Affiliation(s)
- Markus Ingelsson
- Department of Chemical & Petroleum Engineering, University of Calgary, 2500 University Dr NW, Calgary, AB T2N 1N4, Canada
| | - Nael Yasri
- Department of Chemical & Petroleum Engineering, University of Calgary, 2500 University Dr NW, Calgary, AB T2N 1N4, Canada
| | - Edward P L Roberts
- Department of Chemical & Petroleum Engineering, University of Calgary, 2500 University Dr NW, Calgary, AB T2N 1N4, Canada.
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Imidazolium functionalized cellulose filter paper derived from waste newspaper and its application in removal of chromium(VI). REACT FUNCT POLYM 2020. [DOI: 10.1016/j.reactfunctpolym.2020.104776] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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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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