1
|
Agrawal S, Nawaz T. A mechanistic mathematical model for the treatment of synthetic oil-field wastewater (produced water) by electrocoagulation process using aluminium electrodes. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:20117-20132. [PMID: 38374501 DOI: 10.1007/s11356-024-32310-4] [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: 07/18/2023] [Accepted: 01/29/2024] [Indexed: 02/21/2024]
Abstract
Produced water (PW) is the largest by-product that comes out of the oil wells during oil and gas (O&G) field exploration. PW contains high-salt concentration along with other organic and inorganic components; therefore, PW must be treated before disposal. Electrocoagulation (EC) is an effective treatment method to remove pollutants from PW which has been the focus of many experimental studies; however, a mathematical model specifically for PW treatment by EC has not been developed yet. In this work, a comprehensive mathematical model has been developed to elucidate the role of EC operating parameters on the PW treatment performance and determine the mechanism for COD (Chemical Oxygen Demand) removal. The present model considers and identifies the dominant Al-hydroxy complex species and their contribution to the COD removal from synthetic PW samples by estimating their rate constants and comparing their magnitudes and investigates multi-scale modelling of the EC reactor. The influence of working parameters such as current density, initial pH, interelectrode distance, mixing speed and solution volume of PW on Al coagulant production and COD removal was investigated and modelled. The study estimates the rate constants of the reactions taking place for COD removal by EC process and by comparing their magnitudes identifies the dominant reactions and coagulant species involved in the process. The mathematical model prediction of COD removal fits well with the experimental data at 10 mA cm-2, 15 mA cm-2 and 20 mA cm-2 current density with R2 value of 0.96, 0.97 and 0.92, respectively and for dissolved Al concentration R2 value of 0.96, 0.99, and 0.97, respectively. The simulated results reproduced a good fit at initial pH of 6.1, 7.3 and 8.6 with R2 value of 0.92, 0.96 and 0.98, respectively for COD removal. The mathematical model and the experimental results showed the role of dominant Al-hydroxy complex species such asAl OH 2 + ,Al OH 2 + , Al OH 3 ,Al 2 OH 2 + 4 andAl OH 4 - in controlling the COD removal process. Under different operating conditions considered in the study, the model also predicted the COD removal performance of the EC reactors at different reactor volumes with R2 value of 0.96 for higher solution volume and larger reactor. The model presented and rate constants determined in the study will provide a theoretical basis for designing, scaling up and operating the EC reactor for oil-field PW treatment.
Collapse
Affiliation(s)
- Saumya Agrawal
- Environmental Science and Engineering Department (ESED), Indian Institute of Technology Bombay, Mumbai, 400076, India
| | - Tabish Nawaz
- Environmental Science and Engineering Department (ESED), Indian Institute of Technology Bombay, Mumbai, 400076, India.
| |
Collapse
|
2
|
Lu J, Zhang P, Li J, Cao Y, Zhang W, Zhang X, Yi X, Wang H. Mo(VI) removal from water by aluminum electrocoagulation: Cost-effectiveness analysis, main influencing factors, and proposed mechanisms. JOURNAL OF HAZARDOUS MATERIALS 2024; 461:132608. [PMID: 37748311 DOI: 10.1016/j.jhazmat.2023.132608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 09/19/2023] [Accepted: 09/20/2023] [Indexed: 09/27/2023]
Abstract
Mo(VI) (MoO42-) removal by aluminum electrocoagulation (Al EC) with Al as anodes and cathodes was studied for the first time. At the initial Mo concentrations of 0.3 - 150 mg/L, kinetic analysis and effects of main factors (electrode connection modes, current density (CD), initial pH, and electrolytes) were examined, and potential mechanism of Mo(VI) removal were elucidated. Results showed that CD had significant impacts on anode weight loss, cathode weight loss, and total electrode weight loss (p value < 0.05). Cathode weight loss was higher than anode weight loss. XRD analysis results showed lower crystallinity of scums than that of precipitates. Boehmite was the most prevalent oxide in scums. An appropriate amount of NaCl was beneficial for enhancing the Mo(VI) removal efficiency and reducing the energy consumption of the Al EC process. Electrostatic attraction, surface complexation, hydroxyl exchange, flocculation, and coprecipitation were the main mechanisms involved in the Mo(VI) removal process by Al EC. Al EC outperformed conventional chemical coagulation in terms of Mo(VI) removal at the same dosage of Al. The Mo(VI) removal efficiencies in two real water samples (lake water and river water) reached up to 89.2% and 71.2%, respectively. This study provides novel insights into the strategies for the removal of oxoanionic metal pollutants and reduction of operating cost by Al EC technology.
Collapse
Affiliation(s)
- Jianbo Lu
- School of Civil Engineering, Yantai University, Yantai 264005, Shandong, China.
| | - Peng Zhang
- School of Civil Engineering, Yantai University, Yantai 264005, Shandong, China
| | - Jie Li
- School of Economics and Management, Yantai University, Yantai 264005, Shandong, China
| | - Yumin Cao
- School of Civil Engineering, Yantai University, Yantai 264005, Shandong, China
| | - Wei Zhang
- School of Civil Engineering, Yantai University, Yantai 264005, Shandong, China
| | - Xintong Zhang
- School of Civil Engineering, Yantai University, Yantai 264005, Shandong, China
| | - Xuesong Yi
- Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, Hainan University, Haikou 570228, China
| | - Hongjie Wang
- School of Eco-Environment, Hebei University, Baoding 071002, Hebei, China
| |
Collapse
|
3
|
Li H, Zeng Q, Zan F, Lin S, Hao T. In situ coagulation-electrochemical oxidation of leachate concentrate: A key role of cathodes. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2023; 16:100267. [PMID: 37065009 PMCID: PMC10091031 DOI: 10.1016/j.ese.2023.100267] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 02/25/2023] [Accepted: 03/13/2023] [Indexed: 06/19/2023]
Abstract
To efficiently remove organic and inorganic pollutants from leachate concentrate, an in situ coagulation-electrochemical oxidation (CO-EO) system was proposed using Ti/Ti4O7 anode and Al cathode, coupling the "super-Faradaic" dissolution of Al. The system was evaluated in terms of the removal efficiencies of organics, nutrients, and metals, and the underlying cathodic mechanisms were investigated compared with the Ti/RuO2-IrO2 and graphite cathode systems. After a 3-h treatment, the Al-cathode system removed 89.0% of COD and 36.3% of total nitrogen (TN). The TN removal was primarily ascribed to the oxidation of both ammonia and organic-N to N2. In comparison, the Al-cathode system achieved 3-10-fold total phosphorus (TP) (62.6%) and metal removals (>80%) than Ti/RuO2-IrO2 and graphite systems. The increased removals of TP and metals were ascribed to the in situ coagulation of Al(OH)3, hydroxide precipitation, and electrodeposition. With the reduced scaling on the Al cathode surface, the formation of Al3+ and electrified Al(OH)3 lessened the requirement for cathode cleaning and increased the bulk conductivity, resulting in increased instantaneous current production (38.9%) and operating cost efficiencies (48.3 kWh kgCOD -1). The present study indicated that the in situ CO-EO process could be potentially used for treating persistent wastewater containing high levels of organic and inorganic ions.
Collapse
Affiliation(s)
- Huankai Li
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau, China
| | - Qian Zeng
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Feixiang Zan
- School of Environmental Science and Engineering, Low-Carbon Water Environment Technology Center (HUST-SUKE), Huazhong University of Science and Technology, Wuhan, China
| | - Sen Lin
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Tianwei Hao
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau, China
| |
Collapse
|
4
|
Fuladpanjeh-Hojaghan B, Shah RS, Roberts EPL, Trifkovic M. Effect of polarity reversal on floc formation and rheological properties of a sludge formed by the electrocoagulation process. WATER RESEARCH 2023; 242:120201. [PMID: 37336184 DOI: 10.1016/j.watres.2023.120201] [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: 03/16/2023] [Revised: 05/21/2023] [Accepted: 06/07/2023] [Indexed: 06/21/2023]
Abstract
Anode fouling is one of the key limiting factors to the widespread application of electrocoagulation (EC) for treatment of different types of contaminated water. Promising mitigation strategy to fouling is to operate the process under polarity reversal (PR) instead of direct current (DC). However, the PR operation comes at the cost of process complexity due to the alternation of electrochemical and chemical reactions. In this study, we systematically investigated the link between evolving fouling layer during DC and PR close to iron and aluminum electrodes and morphological and rheological properties of the formed sludge. By operando visualization of EC process, we demonstrate that during PR operation, precipitation of the iron and aluminum species occurs close to the anode interface, resulting in flocs with higher porosity and lower density than those formed under DC conditions. However, rheological investigation revealed that the PR conditions resulted in a sludge with more pronounced solid-like signature, but this enhancement in its viscoelastic properties is closely related to a period of the current's polarity reversal. We attribute this unexpected result to higher shear rate and collision of particles during PR conditions.
Collapse
|
5
|
Fadali OA, Ali RH, Nassar MM, Mahmoud MS, Abdel-Aty MM, Barakat NAM. Electromagnetic field-enhanced novel tubular electrocoagulation cell for effective and low-cost color removal of beet sugar industry wastewater. Sci Rep 2023; 13:8693. [PMID: 37248303 DOI: 10.1038/s41598-023-35182-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 05/14/2023] [Indexed: 05/31/2023] Open
Abstract
The treatment of real beet sugar mill effluent by a modified electrocoagulation process is proposed. An innovative design of an electromagnetic field-enhanced electrochemical cell consisting of a tubular screen roll anode and two cathodes (an inner and outer cathode) has been used. Different parameters have been investigated including current density, effluent concentration, NaCl concentration, rpm, number of screen layers per anode, and the effect of addition and direction of an electromagnetic field. The results showed that, under the optimum conditions, current density of 3.13 A/m2, two screens per anode, NaCl concentration of 12 g/l, and rotation speed of 120 rpm, the percentage of color removal was 85.5% and the electrical energy consumption was 3.595 kWh/m3. However, the presence of an electromagnetic field distinctly enhanced the energy consumption and the color removal percentage. Numerically, applying the magnetic field resulted in performing a color removal efficiency of 97.7% using a power consumption of 2.569 KWh/m3 which is considered a distinct achievement in industrial wastewater treatment process. The strong enhancement in color removal using a low power consumption significantly reduced the required treatment cost; the estimated treatment cost was 0.00017 $/h.m2. This design has proven to be a promising one for the continuous treatment of beet sugar industrial effluents and to be a competitor to the currently available techniques.
Collapse
Affiliation(s)
- Olfat A Fadali
- Faculty of Engineering, Chemical Engineering Department, Minia University, El-Minia, 61516, Egypt
| | - Rasha H Ali
- Faculty of Engineering, Chemical Engineering Department, Minia University, El-Minia, 61516, Egypt
| | - Mamdouh M Nassar
- Faculty of Engineering, Chemical Engineering Department, Minia University, El-Minia, 61516, Egypt
| | - Mohamed S Mahmoud
- Faculty of Engineering, Chemical Engineering Department, Minia University, El-Minia, 61516, Egypt
- Department of Engineering, University of Technology and Applied Sciences, 311, Suhar, Oman
| | - Marwa M Abdel-Aty
- Faculty of Engineering, Chemical Engineering Department, Minia University, El-Minia, 61516, Egypt
| | - Nasser A M Barakat
- Faculty of Engineering, Chemical Engineering Department, Minia University, El-Minia, 61516, Egypt.
| |
Collapse
|
6
|
Madrid FMG, Arancibia-Bravo MP, Sepúlveda FD, Lucay FA, Soliz A, Cáceres L. Ultrafine Kaolinite Removal in Recycled Water from the Overflow of Thickener Using Electroflotation: A Novel Application of Saline Water Splitting in Mineral Processing. Molecules 2023; 28:molecules28093954. [PMID: 37175364 PMCID: PMC10180029 DOI: 10.3390/molecules28093954] [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: 03/04/2023] [Revised: 04/21/2023] [Accepted: 04/28/2023] [Indexed: 05/15/2023] Open
Abstract
The presence of ultrafine clay particles that are difficult to remove by conventional filtration creates many operational problems in mining processing systems. In this work, the removal of clay suspensions has been investigated using an electroflotation (EF) process with titanium electrodes. The results show that EF is a viable and novel alternative for removing ultrafine particles of kaolinite-type clay present in sedimentation tank overflows with low salt concentrations (<0.1 mol/L) in copper mining facilities based on the saline water splitting concept. Maximum suspended solid removal values of 91.4 and 83.2% in NaCl and KCl solutions, respectively, were obtained under the experimental conditions of the constant applied potential of 20 V/SHE, salinity concentration of 0.1 mol/L, and electroflotation time of 10 and 20 min in NaCl and KCl solutions, respectively. Furthermore, the visual evidence of particle aggregation by flocculation during the experiments indicates a synergy between EF and electrocoagulation (EC) that enhances the removal of ultrafine particles of kaolinite.
Collapse
Affiliation(s)
| | | | - Felipe D Sepúlveda
- Departamento de Ingeniería en Minas, Universidad de Antofagasta, Antofagasta 1240000, Chile
| | - Freddy A Lucay
- Escuela de Ingeniería Química, Pontificia Universidad Católica de Valparaíso, Valparaíso 2374631, Chile
| | - Alvaro Soliz
- Departamento de Ingeniería en Metalurgia, Universidad de Atacama, Copiapó 1531772, Chile
| | - Luis Cáceres
- Departamento de Ingeniería Química y Procesos de Minerales, Universidad de Antofagasta, Antofagasta 1240000, Chile
| |
Collapse
|
7
|
Hu Q, He L, Lan R, Feng C, Pei X. Recent advances in phosphate removal from municipal wastewater by electrocoagulation process: A review. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2022.122944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
8
|
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.
Collapse
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
| |
Collapse
|
9
|
Sharaj Sharifi N, Karimi-Jashni A. Development and application of novel high throughput metal waste chips and foam electrodes for electrocoagulation treatment of graywater. ENVIRONMENTAL TECHNOLOGY 2023; 44:528-539. [PMID: 34479462 DOI: 10.1080/09593330.2021.1976845] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 08/22/2021] [Indexed: 06/13/2023]
Abstract
In this study, novel high throughput metal waste chips and foam electrodes were developed for the electrocoagulation of graywater for the first time. The developed electrodes were then compared with traditional metal plate electrodes, which showed higher efficiency of developed electrodes. The effective parameters of pH, electrode distance, applied voltage, and reaction time on COD removal were optimized using RSM as a multivariate optimization technique, and the data were analyzed by ANOVA, normal plot, residual distribution, and 3D plots. The optimal conditions for electrocoagulation of graywater using metal (Al) plate electrode were determined as a pH of 6.86, electrode distance of 5 mm, and applied voltage of 5 V for a reaction time of 10 min, resulting in 89.1% COD removal and 74% turbidity removal. Finally, the performance of aluminum plate electrodes, foam electrodes, and electrodes made from metal waste chips was compared using COD removal efficiency as the index, revealing 84%, 93%, and 87% COD removal, respectively. These results demonstrated that the newly developed electrodes are suitable for graywater treatment with excellent COD removal efficiency, metal chip waste recycling, and cost-saving.
Collapse
Affiliation(s)
- Niloofar Sharaj Sharifi
- School of Engineering, Department of Civil and Environmental Engineering, Shiraz University, Shiraz, Iran
| | - Ayoub Karimi-Jashni
- School of Engineering, Department of Civil and Environmental Engineering, Shiraz University, Shiraz, Iran
| |
Collapse
|
10
|
Ashoori R, Samaei MR, Yousefinejad S, Azhdarpoor A, Emadi Z, Mohammadpour A, Lari AR, Mousavi Khaneghah A. Simultaneous removal of fluoride and nitrate from synthetic aqueous solution and groundwater by the electrochemical process using non-coated and coated anode electrodes: A human health risk study. ENVIRONMENTAL RESEARCH 2022; 214:113938. [PMID: 35977584 DOI: 10.1016/j.envres.2022.113938] [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: 03/21/2022] [Revised: 07/10/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
Co-presence of fluoride (F-) and nitrate (NO3-) in water causes numerous health complications. Thus, they should be eliminated by an appropriate method like the EC process. In this research, simultaneous removal of F- and NO3- from synthetic aqueous solution and groundwater has been considered by the EC technique under operational parameters like anode materials (un-coated (Al and Fe) and synthesized coated (Ti/TiRuSnO2 and Ti/PbO2)), cathode materials (Cu, St, and Gr), current density (12, 24, and 36 mA/cm2), inter-electrode distance (0.5, 1, and 2 cm), pH (5.5, 7, and 8.5), NaCl concentrations (0.5, 1, and 1.5 g/L), electrolysis time (15, 30, 45, 60, 90, and 120 min), NO3- concentrations (75, 150, and 225 mg/L), and F- concentrations (2, 4, 6, and 8 mg/L) for the first time in this research. The results proved that Al as non-coated anode and Cu as cathode electrodes were more effective in the co-removal of F- and NO3-. The maximum removal efficiencies of 94.19 and 95% were observed at the current density of 36 mA/cm2, 1 cm of inter-electrode distance, pH 7, 1 g/L of NaCl, and 90 min electrolysis time by Al-Cu electrode for F- (2 mg/L) and NO3- (75 mg/L), respectively. The higher efficiency of Al-Cu electrodes was due to the simultaneous occurrence of electrocoagulation, electroreduction, and electrooxidation processes. Al-Cu electrode application considerably diminished f- and NO3- concentrations in the groundwater. Health risk assessment proved that HQ of F- was significantly decreased after treatment by the Al-Cu electrode. Thus, the EC process using an appropriate and effective electrode is a promising technique for treating aqueous solutions containing F- and NO3-.
Collapse
Affiliation(s)
- Razieh Ashoori
- Department of Environmental Health Engineering, School of Health, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohammad Reza Samaei
- Department of Environmental Health Engineering, School of Health, Shiraz University of Medical Sciences, Shiraz, Iran.
| | - Saeed Yousefinejad
- Research Center for Health Sciences, Institute of Health, Department of Occupational Health Engineering, School of Health, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Abooalfazl Azhdarpoor
- Department of Environmental Health Engineering, School of Health, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Zahra Emadi
- Department of Environmental Health Engineering, School of Health, Shahrekord University of Medical Sciences, Shahrekord, Iran
| | - Amin Mohammadpour
- Department of Chemical Engineering, School of Chemical and Petroleum Engineering, Shiraz University, 71946-84636 Shiraz, Iran
| | - Ali Rasti Lari
- School of Civil and Environmental Engineering, University of Technology Sydney, 15 Broadway, NSW, 2007, Australia
| | - Amin Mousavi Khaneghah
- Department of Fruit and Vegetable Product Technology, Prof. Wacław Dąbrowski Institute of Agricultural and Food Biotechnology - State Research Institute, 36 Rakowiecka St., 02-532, Warsaw, Poland.
| |
Collapse
|
11
|
Sun J, Huo J, Li B, Gu Z, Hu C, Qu J. Anode passivation mitigation by homogenizing current density distribution in electrocoagulation. WATER RESEARCH 2022; 223:118966. [PMID: 35973250 DOI: 10.1016/j.watres.2022.118966] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 07/12/2022] [Accepted: 08/07/2022] [Indexed: 06/15/2023]
Abstract
Electrode passivation is the most challenging technical problem in electrocoagulation (EC) water treatment process, but research on understanding and mitigating passivation evolution are still lacking. Herein, homogenization of current density (CD) distribution was found to be a critical factor in alleviating the anode passivation during EC process. Decreasing electrode area decelerated the growth of passivation layer on anode through homogenizing CD distribution, which was quantified by the ratios of CD distributed at the electrode edges and centers. When aluminum anode area decreased from 8 cm2 to 2 cm2 with a constant CD, the homogenization degree increased by 24.0%, and passivation was reduced by 24.3%. The depth profiles of passivated anodes confirmed the inhomogeneity of the anode passivation. Thicker passivation layers were observed at edges due to high CD distributions, which originated from the "edge effect" of electric field distribution between parallel plate electrodes. A facile strategy to homogenize CD distribution by splitting electrodes into smaller electrodes is then proposed for passivation mitigation, which can save energy consumption by 21.8% with unchanged removal efficiency. This study provides a unique insight into anode passivation mitigation and a feasible electrode design in EC.
Collapse
Affiliation(s)
- Jingqiu Sun
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China; Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Jiawen Huo
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China
| | - Bowen Li
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China
| | - Zhenao Gu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chengzhi Hu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Jiuhui Qu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
12
|
On the specific limitations of titanium electrodes in the electrocoagulation process. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.129196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
13
|
Lu J, Fan R, Wu H, Zhang W, Li J, Zhang X, Sun H, Liu D. Simultaneous removal of Cr(VI) and Cu(II) from acid wastewater by electrocoagulation using sacrificial metal anodes. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119276] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
14
|
Xie Y, Meng X, Chang Y, Mao D, Qin Z, Wan L, Huang Y. Heteroatom Modification Enhances Corrosion Durability in High-Mechanical-Performance Graphene-Reinforced Aluminum Matrix Composites. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2104464. [PMID: 35703130 PMCID: PMC9376822 DOI: 10.1002/advs.202104464] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 05/16/2022] [Indexed: 05/13/2023]
Abstract
The antagonism between strength and corrosion resistance in graphene-reinforced aluminum matrix composites is an inherent challenge to designing reliable structural components. Heteroatom microstructural modification is highly appreciated to conquer the obstacle. Here, a bottom-up strategy to exploit the heterogeneous phase interface to enable high corrosion durability is proposed. Deformation-driven metallurgy derived from severe plastic deformation is developed to produce Mg-alloyed fluorinated graphene structures with homogeneous dispersion. These structures allow for absorbing corrosion products, forming a dense protective layer against corrosion, and local micro-tuning of the suppression of charge transfer. This results in superior corrosion resistance with an outstanding strength-ductility balance of the composites via ultrafine-grained and precipitation strengthening. The anti-corrosion polarization resistance remains 89% of the initial state after 2-month immersion in chloride-containing environment, while the ultra-tensile strength and elongation of 532 ± 39 MPa and 17.3 ± 1.2% are obtained. The economical strategy of heteroatom modification broadens the horizon for anti-corrosion engineering in aluminum matrix composites, which is critical for the design of carbonaceous nanomaterial-reinforced composites to realize desired performances for practical applications.
Collapse
Affiliation(s)
- Yuming Xie
- State Key Laboratory of Advanced Welding and JoiningHarbin Institute of TechnologyHarbin150001China
| | - Xiangchen Meng
- State Key Laboratory of Advanced Welding and JoiningHarbin Institute of TechnologyHarbin150001China
| | - Yuexin Chang
- State Key Laboratory of Advanced Welding and JoiningHarbin Institute of TechnologyHarbin150001China
| | - Dongxin Mao
- State Key Laboratory of Advanced Welding and JoiningHarbin Institute of TechnologyHarbin150001China
| | - Zhiwei Qin
- State Key Laboratory of Advanced Welding and JoiningHarbin Institute of TechnologyHarbin150001China
| | - Long Wan
- State Key Laboratory of Advanced Welding and JoiningHarbin Institute of TechnologyHarbin150001China
| | - Yongxian Huang
- State Key Laboratory of Advanced Welding and JoiningHarbin Institute of TechnologyHarbin150001China
| |
Collapse
|
15
|
Environmental and economic feasibility of the treatment of dairy industry wastewater by photo-Fenton and electrocoagulation process: Multicriteria optimization by desirability function. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2022.113820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
16
|
Electrochemical Synthesis of Precursors of Al2O3-ZrO2 Ceramic Stabilized with Cerium Oxide and Magnesium Aluminate. INORGANICS 2022. [DOI: 10.3390/inorganics10050057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
This article presents a new approach to preparing the precursors of complex oxide systems Al2O3-ZrO2-MXOY (M = Mg, Ce). The approach is based on the electrogeneration and interaction of reagents with electrolyte components in a coaxial electrochemical reactor. The design of the electrolyzer provides the suspension homogenization due to the turbulence induced by the intensive hydrogen bubbles and electrolyte movement in opposite directions relative to the central electrode in a closed space. Hydrogen evolution leads to the mixing of the solution. The transfer of OH− ions generated at the cathode into the electrolyte and interaction with metal ions (Zr, Al, Ce, Mg) leads to the formation of hydroxoaqua complexes of these metals. They participate in the polycondensation reaction, forming polymerized hydroxides and oxyhydroxides, which are the basis of the primary particles. The process of hydroxylation of nanoparticle surface of the formed precursors of oxide systems stabilizes the dispersion and prevents particle aggregation. The stabilized tetragonal t-ZrO2 was obtained by sintering the precursor of the synthesized oxide system at 1100 °C with the formation of an alumina phase (γ-Al2O3, or an aluminum–magnesium spinel MgAl2O4) with a low CeO2 content (2–3 wt%).
Collapse
|
17
|
Treatment of arsenite contaminated water by electrochemically activated persulfate oxidation process. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2021.119999] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
18
|
Costa AM, Zanoelo EF, Benincá C, Freire FB. A kinetic model for electrocoagulation and its application for the electrochemical removal of phosphate ions from brewery wastewater. Chem Eng Sci 2021. [DOI: 10.1016/j.ces.2021.116755] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
19
|
Effects of some ion-specific properties in the electrocoagulation process with aluminum electrodes. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.127507] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
20
|
Chow H, Ingelsson M, Roberts EPL, Pham ALT. How does periodic polarity reversal affect the faradaic efficiency and electrode fouling during iron electrocoagulation? WATER RESEARCH 2021; 203:117497. [PMID: 34371234 DOI: 10.1016/j.watres.2021.117497] [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] [Received: 05/10/2021] [Revised: 07/26/2021] [Accepted: 07/27/2021] [Indexed: 06/13/2023]
Abstract
Electrocoagulation (EC) is a promising electrochemical water treatment technology. However, a major challenge to sustaining effective long-term EC operation is controlling the precipitation of materials on the electrodes, commonly referred to as fouling. Periodically reversing electrode polarity has been suggested as an in-situ fouling mitigation strategy and is often implemented in EC field applications. However, the utility of this approach has not been investigated in detail. In this study, the effect of polarity reversal (PR) on the performance of EC using iron electrodes was examined under different water chemistry conditions and at a range of reversal frequencies. It was observed that the faradaic efficiency in PR-EC was always lower than that in the EC systems operated with a direct current (i.e., DC-EC). It was also observed that the faradaic efficiency progressively decreased as the current reversal frequency increased, with the faradaic efficiency dropping as low as 10% when the PR interval was 0.5 min. Results from fouling layer, chronopotentiometric, and cyclic voltammetric investigations indicated that the decrease in the faradaic efficiency was caused by (i) increased electrode fouling by iron precipitates and (ii) electrochemical side reactions at the electrode-electrolyte interface. The extent of these effects was dependent on the solution chemistry; oxyanions and sulfide were found to be particularly detrimental to the performance of PR-EC, causing severe electrode fouling while decreasing the faradaic efficiency. Fouling could be mitigated by increasing the solution convection rate, resulting in a shear on the electrode surface that removed iron and other electrochemically reactive species from the electrodes.
Collapse
Affiliation(s)
- Héline Chow
- Department of Civil and Environmental Engineering, University of Waterloo, Waterloo, Ontario ON N2L 3G1, Canada
| | - Markus Ingelsson
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta T2N 1NF, Canada
| | - Edward P L Roberts
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta T2N 1NF, Canada.
| | - Anh Le-Tuan Pham
- Department of Civil and Environmental Engineering, University of Waterloo, Waterloo, Ontario ON N2L 3G1, Canada.
| |
Collapse
|
21
|
Oliveira JT, de Sousa MC, Martins IA, de Sena LMG, Nogueira TR, Vidal CB, Neto EFA, Romero FB, Campos OS, do Nascimento RF. Electrocoagulation/oxidation/flotation by direct pulsed current applied to the removal of antibiotics from Brazilian WWTP effluents. Electrochim Acta 2021. [DOI: 10.1016/j.electacta.2021.138499] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
22
|
Use of Electrocoagulation for Treatment of Pharmaceutical Compounds in Water/Wastewater: A Review Exploring Opportunities and Challenges. WATER 2021. [DOI: 10.3390/w13152105] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Increasing dependency on pharmaceutical compounds including antibiotics, analgesics, antidepressants, and other drugs has threatened the environment as well as human health. Their occurrence, transformation, and fate in the environment are causing significant concerns. Several existing treatment technologies are there with their pros and cons for the treatment of pharmaceutical wastewater (PWW). Still, electrocoagulation is considered as the modern and decisive technology for treatment. In the EC process, utilizing electricity (AC/DC) and electrodes, contaminants become coagulated with the metal hydroxide and are separated by co-precipitation. The main mechanism is charge neutralization and adsorption of contaminants on the generated flocs. The range of parameters affects the EC process and is directly related to the removal efficiency and its overall operational cost. This process only could be scaled up on the industrial level if process parameters become optimized and energy consumption is reduced. Unfortunately, the removal mechanism of particular pharmaceuticals and complex physiochemical phenomena involved in this process are not fully understood. For this reason, further research and reviews are required to fill the knowledge gap. This review discusses the use of EC for removing pharmaceuticals and focuses on removal mechanism and process parameters, the cost assessment, and the challenges involved in mitigation.
Collapse
|
23
|
Yu Y, Zhong Y, Wang M, Guo Z. Electrochemical behavior of aluminium anode in super-gravity field and its application in copper removal from wastewater by electrocoagulation. CHEMOSPHERE 2021; 272:129614. [PMID: 33482514 DOI: 10.1016/j.chemosphere.2021.129614] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 01/04/2021] [Accepted: 01/08/2021] [Indexed: 06/12/2023]
Abstract
Anodic passivation is a key problem to reduce the efficiency of electrocoagulation (EC) process. Super-gravity technology was introduced into EC process to enhance the treatment of heavy metal wastewater using pure aluminum electrode. The results showed that the removal ratio of Cu increased, and the cell voltage decreased with the increase of gravity coefficient, suggesting a promoting effect of super-gravity field on electrocoagulation process. Electrochemical behavior of aluminium anode in super-gravity field was analyzed by potentiodynamic polarization, cyclic voltammetry and electrochemical impedance spectroscopy. It was found that anodic polarization behavior of aluminium showed a typical characteristic of dissolution in super-gravity, rather than passivation in normal gravity. The type of anode dissolution changed from pitting corrosion to uniform corrosion in super-gravity field. The outer oxidized film of anode was thinning, and more Al3+ ions were released by anode dissolution, which was attributed to the super-gravity enhancement of the mass transfer process of Cl- ions. In addition, X-ray diffraction and Fourier transform infrared spectroscopy indicated that the flocs generated in super-gravity field had amorphous and looser Al-O framework structure. As a result, the efficiency of EC process was improved by super-gravity.
Collapse
Affiliation(s)
- Yu Yu
- State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing, 100083, PR China
| | - Yiwei Zhong
- State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing, 100083, PR China.
| | - Mingyong Wang
- State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing, 100083, PR China
| | - Zhancheng Guo
- State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing, 100083, PR China
| |
Collapse
|
24
|
Saad MS, Wirzal MDH, Putra ZA. Review on current approach for treatment of palm oil mill effluent: Integrated system. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 286:112209. [PMID: 33631516 DOI: 10.1016/j.jenvman.2021.112209] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/02/2021] [Accepted: 02/14/2021] [Indexed: 06/12/2023]
Abstract
Malaysia is one of the countries that is well known for its palm oil based products and exports all over the world. Over the years, palm oil mill has been rising at alarming rate in Malaysia, causing palm oil-based wastes to increase especially palm oil mill effluent (POME). POME in Malaysia are channelled into water bodies such as rivers after treated mostly with conventional biological method. However, with current technologies and knowledge, conventional POME treatments are seen to be outdated and require major improvements as greenhouse gaseous are emitted to the environment as well as being less cost effective. Integrated systems that combine two or more conventional methods are introduced and reviewed to provide insights on the advantages and disadvantages of the system if it is to be implemented in real life plant. Integrated systems that focus on combining conventional methods are compiled and reviewed specifically for POME treatment. Among the integrated methods that are reviewed includes biological with membrane, adsorption with magnetic field exposure, adsorption with membrane and electrocoagulation with membrane. The systems are seen to give excellent color, chemical oxygen demand (COD) and total suspended solids (TSS) removal with average of higher than 90%. Reduction in space utilization, improved treatment time as well as simplified operating system were reported when integrated systems are applied as compared to conventional treatment of POME.
Collapse
Affiliation(s)
- Muhammad Syaamil Saad
- Chemical Engineering Department, Universiti Teknologi PETRONAS, 32610, Bandar Seri Iskandar, Perak, Malaysia
| | - Mohd Dzul Hakim Wirzal
- Chemical Engineering Department, Universiti Teknologi PETRONAS, 32610, Bandar Seri Iskandar, Perak, Malaysia.
| | - Zulfan Adi Putra
- PETRONAS Group Technical Solutions, Project Delivery and Technology, PETRONAS, Kuala Lumpur, 50050, Malaysia
| |
Collapse
|
25
|
Kano K, Hagiwara S, Igarashi T, Otani M. Study on the free corrosion potential at an interface between an Al electrode and an acidic aqueous NaCl solution through density functional theory combined with the reference interaction site model. Electrochim Acta 2021. [DOI: 10.1016/j.electacta.2021.138121] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
|
26
|
Sandoval MA, Fuentes R, Thiam A, Salazar R. Arsenic and fluoride removal by electrocoagulation process: A general review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 753:142108. [PMID: 33207438 DOI: 10.1016/j.scitotenv.2020.142108] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 08/20/2020] [Accepted: 08/29/2020] [Indexed: 06/11/2023]
Abstract
The environmental sector has expressed a growing interest in using electrocoagulation (EC) to treat groundwater/wastewater for drinking/recycling purposes. In the EC process, the electro-dissolution of sacrificial metallic anodes through direct application of current/cell potential dissolves the metals, which precipitate as oxides and hydroxides depending on the electrolyte pH. These particles have large surface areas and can remove pollutants by coagulation. The EC process has been considered an alternative technology due to its versatility, efficiency, low cost, and environmental compatibility. Unfortunately, the lack of knowledge about scaling-up this process has limited its implementation at the industrial scale. The aim of this study is to provide a review of the EC process used for removing arsenic and fluoride from groundwater and wastewater. Approximately 80 published studies were reviewed for this paper. The fundamentals of the EC process and importance of its operating conditions, i.e., electrode material, current density, supporting electrolyte, and pH, are reported in this paper. Additionally, overview of floc characterization and energy consumption are also presented. Finally, this paper also discusses the future perspectives.
Collapse
Affiliation(s)
- Miguel A Sandoval
- Universidad de Santiago de Chile USACH, Facultad de Química y Biología, Departamento de Química de los Materiales, Laboratorio de Electroquímica Medio Ambiental, LEQMA, Casilla 40, Correo 33, Santiago, Chile; Universidad de Guanajuato, División de Ciencias Naturales y Exactas, Departamento de Ingeniería Química, Noria Alta S/N, 36050, Guanajuato, Guanajuato, Mexico.
| | - Rosalba Fuentes
- Universidad de Guanajuato, División de Ciencias Naturales y Exactas, Departamento de Ingeniería Química, Noria Alta S/N, 36050, Guanajuato, Guanajuato, Mexico
| | - Abdoulaye Thiam
- Programa Institucional de Fomento a la I+D+i, Universidad Tecnológica Metropolitana, Ignacio Valdivieso 2409, P.O. Box 8940577, San Joaquín, Santiago, Chile
| | - Ricardo Salazar
- Universidad de Santiago de Chile USACH, Facultad de Química y Biología, Departamento de Química de los Materiales, Laboratorio de Electroquímica Medio Ambiental, LEQMA, Casilla 40, Correo 33, Santiago, Chile.
| |
Collapse
|
27
|
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.
Collapse
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.
| |
Collapse
|
28
|
Nyangi MJ, Chebude Y, Kilulya KF, Andrew M. Simultaneous removal of fluoride and arsenic from water by hybrid Al-Fe electrocoagulation: process optimization through surface response method. SEP SCI TECHNOL 2020. [DOI: 10.1080/01496395.2020.1837877] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Magori J. Nyangi
- Africa Centre of Excellence for Water Management, The Addis Ababa University, Addis Ababa, Ethiopia
- Department of Water Resources, Water Institute, Dar Es Salaam, Tanzania
| | - Yonas Chebude
- Africa Centre of Excellence for Water Management, The Addis Ababa University, Addis Ababa, Ethiopia
| | - Kessy F. Kilulya
- Department of Chemistry, College of Natural and Applied Sciences, the University of Dar Ss Salaam, Dar Es Salaam, Tanzania
| | - Minu Andrew
- Department of Research and Innovation, Tanzania Commission for Science and Technology, Dar Es Salaam, Tanzania
| |
Collapse
|
29
|
El-Ghenymy A, Alsheyab M, Khodary A, Sirés I, Abdel-Wahab A. Corrosion behavior of pure titanium anodes in saline medium and their performance for humic acid removal by electrocoagulation. CHEMOSPHERE 2020; 246:125674. [PMID: 31884228 DOI: 10.1016/j.chemosphere.2019.125674] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Accepted: 12/13/2019] [Indexed: 06/10/2023]
Abstract
The corrosion behavior of Ti electrodes and the dependence of their anodic dissolution with the experimental conditions, namely pH, current density (j) and supporting electrolyte nature, have been investigated. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests have been performed. It has been found that pH has a relevant effect on the electrochemical dissolution of Ti. In chloride medium, metal dissolution was partially caused by pitting corrosion and the corrosion potential was shifted to more cathodic values. Conversely, in phosphate medium, corrosion was inhibited by the formation of a compact passive layer of titanium hydroxide/phosphate. Further, the mechanisms of sacrificial Ti anode dissolution during the electrocoagulation process are discussed. The influence of the supporting electrolyte, pH and j on the effectiveness of the electrocoagulation process for humic acid (HA) removal was assessed. Under optimized conditions, total decolorization was achieved in 60 min, eventually attaining 94% total organic carbon (TOC) removal.
Collapse
Affiliation(s)
- Abdellatif El-Ghenymy
- Chemical Engineering Program, Texas A&M University at Qatar, P.O. Box 23874, Doha, Qatar.
| | - Mohammad Alsheyab
- Research Expert and Consultant, Civil and Environmental Engineering, and Senior Expert of Environmental Development, Planning and Statistics Authority, Doha, Qatar
| | | | - Ignasi Sirés
- Laboratori d'Electroquímica dels Materials i del Medi Ambient, Departament de Química Física, Facultat de Química, Universitat de Barcelona, Martí i Franquès 1-11, 08028, Barcelona, Spain.
| | - Ahmed Abdel-Wahab
- Chemical Engineering Program, Texas A&M University at Qatar, P.O. Box 23874, Doha, Qatar
| |
Collapse
|
30
|
|
31
|
Maitlo HA, Lee J, Park JY, Kim JC, Kim KH, Kim JH. An energy-efficient air-breathing cathode electrocoagulation approach for the treatment of arsenite in aquatic systems. J IND ENG CHEM 2019. [DOI: 10.1016/j.jiec.2019.01.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
32
|
Arturi TS, Seijas CJ, Bianchi GL. A comparative study on the treatment of gelatin production plant wastewater using electrocoagulation and chemical coagulation. Heliyon 2019; 5:e01738. [PMID: 31193809 PMCID: PMC6543083 DOI: 10.1016/j.heliyon.2019.e01738] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 04/26/2019] [Accepted: 05/13/2019] [Indexed: 10/26/2022] Open
Abstract
Effluents from gelatin production plants are highly complex and difficult to treat by conventional methods. The Electrocoagulation (EC) technique was evaluated to treat effluents that contain a heavy load of Chemical Oxygen Demand (COD) and a large quantity of suspended solids. This paper presents results of laboratory scale studies that compare the performance of Chemical Coagulation (CC) with aluminum salts and EC with aluminum electrodes. The heavy organic load and suspended solids in this kind of wastewater lead to low performance in the secondary treatment. SEM-EDS were used to analyze the sludge formed in the EC process and the removal mechanism of pollutants from the wastewater. The structure and composition of the precipitates at different operation conditions, such as pH, show that EC has increased efficiency of COD removal, compared to CC with the same dose of aluminum (Al+3) as coagulant. The efficiency of COD removal was 73.6% with EC and 55.6% with CC. The in-situ formation of zeolites in the EC process explains the high efficiency of this treatment compared to the CC process. The zeolite formation during the EC process in the wastewater of the gelatin production plant has not been reported until now.
Collapse
Affiliation(s)
| | | | - Gustavo L. Bianchi
- Energy and Environmental Innovation Group, Malvinas Institute, Faculty of Engineering, National University of La Plata, Diagonal 80 No 372, La Plata, Buenos Aires, 1900, Argentina
| |
Collapse
|
33
|
Removal mechanism for chromium (VI) in groundwater with cost-effective iron-air fuel cell electrocoagulation. Sep Purif Technol 2019. [DOI: 10.1016/j.seppur.2018.12.058] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|
34
|
Dura A, Breslin CB. Electrocoagulation using aluminium anodes activated with Mg, In and Zn alloying elements. JOURNAL OF HAZARDOUS MATERIALS 2019; 366:39-45. [PMID: 30502571 DOI: 10.1016/j.jhazmat.2018.11.094] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Revised: 11/21/2018] [Accepted: 11/23/2018] [Indexed: 06/09/2023]
Abstract
The simultaneous removal of phosphates, Zn2+ and Orange II, in two synthetic wastewaters was achieved using Al-Mg and Al-Zn-In alloys as anodes at 11.7 mA cm-2 and a surface area to volume ratio of 19.0 m-1. Higher removal efficiencies were obtained with Al-Zn-In, attaining values of 95-96% for phosphate, 99% for Zn2+ and 88-96% for Orange II, while somewhat lower values were seen with Al-Mg, with 89-93% for phosphate, 96% for Zn2+ and 50-60% for Orange II, depending on the solution. The higher efficiency with Al-Zn-In was attributed to its less passive behaviour, which was evident from polarisation plots. Numerous shallow pits, resembling general-like dissolution, were seen with Al-Zn-In, while fewer and larger pits were observed with Al-Mg. The energy demand for the removal of the pollutants was computed as 1.30 and 2.55 kWh m-3 for the Al-Zn-In and Al-Mg anodes, respectively. The removal of phosphates and Orange II was explained in terms of the generation of cationic polynuclear aluminium species that provide electrostatic interactions with the anionic phosphates and Orange II. The removal of Zn2+ was attributed to the formation of insoluble Zn(OH)2.
Collapse
Affiliation(s)
- Adelaide Dura
- Department of Chemistry, Maynooth University, Maynooth, County Kildare, Ireland
| | - Carmel B Breslin
- Department of Chemistry, Maynooth University, Maynooth, County Kildare, Ireland.
| |
Collapse
|
35
|
Nath SD, Irrinki H, Gupta G, Kearns M, Gulsoy O, Atre S. Microstructure-property relationships of 420 stainless steel fabricated by laser-powder bed fusion. POWDER TECHNOL 2019. [DOI: 10.1016/j.powtec.2018.11.075] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
36
|
Govindan K, Angelin A, Rangarajan M. Critical evaluation of mechanism responsible for biomass abatement during electrochemical coagulation (EC) process: A critical review. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 227:335-353. [PMID: 30199730 DOI: 10.1016/j.jenvman.2018.08.100] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 08/15/2018] [Accepted: 08/26/2018] [Indexed: 06/08/2023]
Abstract
This is a first review paper that delineates fundamental disinfection mechanism undergoes during the simple electrochemical coagulation (EC) process. The elucidation of detailed mechanistic phenomenon of EC process involved would help to enhance the disinfection efficiency. In this context, the biomass (bacteria, virus and algae) abatement mechanism by EC is critically reviewed and rationalized based on the experimental demonstration performed from the recent decade. Whereas, the effect of most significant abiotic operating parameters, dissolved contents and bacteria cell wall composition on biomass reduction are explored in detail. From these analyses, physical removal and chemical inactivation routes are identified for bacteria abatement mechanism during the EC process using sacrificial electrodes. Which includes (i) enmeshment of microbial contaminants by EC flocs, (ii) sweeping flocculation is preferentially for destabilization of negatively charged biomass, and (iii) inactivation/attenuation of micro-organism cell walls by electrochemically induced reactive oxygen species (ROS) or direct interaction of electric field. Perhaps, the overall abatement mechanism attributes due to the aforementioned phenomenon endures independently and/or synergistically during the EC process. Nonetheless, to obtain better understanding of virus and algae abatement mechanism, we require more experimental investigation on algae and virus removal. Eventually, more intensive research efforts on biomass attenuation by EC are most important to reinforce this claim.
Collapse
Affiliation(s)
- Kadarkarai Govindan
- Center of Excellence in Advanced Materials and Green Technologies, Department of Chemical Engineering and Material Science, Amrita School of Engineering Coimbatore, Amrita Vishwa Vidyapeetham, Amrita University, Coimbatore, Tamil Nadu, 641 112, India.
| | - Arumugam Angelin
- Department of Biotechnology, Karunya Institute of Technology and Sciences, Coimbatore, 641 114, Tamil Nadu, India
| | - Murali Rangarajan
- Center of Excellence in Advanced Materials and Green Technologies, Department of Chemical Engineering and Material Science, Amrita School of Engineering Coimbatore, Amrita Vishwa Vidyapeetham, Amrita University, Coimbatore, Tamil Nadu, 641 112, India
| |
Collapse
|
37
|
Zhou Y, Hu Y, Gong X, Wang Z, Zhang S, Wang M. Intensified hydrogen production and desulfurization at elevated temperature and pressure during coal electrolysis. Electrochim Acta 2018. [DOI: 10.1016/j.electacta.2018.07.204] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
38
|
Effects of supporting electrolytes in treatment of arsenate-containing wastewater with power generation by aluminumair fuel cell electrocoagulation. J IND ENG CHEM 2018. [DOI: 10.1016/j.jiec.2017.08.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
39
|
Hakizimana JN, Najid N, Gourich B, Vial C, Stiriba Y, Naja J. Hybrid electrocoagulation/electroflotation/electrodisinfection process as a pretreatment for seawater desalination. Chem Eng Sci 2017. [DOI: 10.1016/j.ces.2017.04.029] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
40
|
Wang Y, Lin H, Jin F, Niu J, Zhao J, Bi Y, Li Y. Electrocoagulation mechanism of perfluorooctanoate (PFOA) on a zinc anode: Influence of cathodes and anions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 557-558:542-550. [PMID: 27037875 DOI: 10.1016/j.scitotenv.2016.03.114] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 03/16/2016] [Accepted: 03/16/2016] [Indexed: 06/05/2023]
Abstract
Batch experiments were conducted to investigate the effects of cathode materials and anions (Cl(-), SO4(2-), NO3(-), and CO3(2-)/HCO3(-)) on perfluorooctanoate (PFOA) removal in electrocoagulation process using zinc anode. The results indicated that the hydroxide flocs generated in-situ in the electrocoagulation process using the stainless steel rod as cathode were more effective than those using aluminum rod as cathode for the removal of PFOA after 20min of electrocoagulation at a current density of 0.5mAcm(-2). Hydroxide flocs generated in-situ in the electrocoagulation in the presence of Cl(-)/NO3(-) could effectively remove PFOA from aqueous solution with the removal ratios of 99.7%/98.1% and 98.9%/97.3% using stainless steel rod and aluminum rod as cathode, respectively. However, the PFOA removal ratios were 96.2%/4.1% and 7.4%/4.6% using stainless steel rod and aluminum rod as cathode, respectively, in the presence of SO4(2-) and CO3(2-)/HCO3(-). The different removal ratios of PFOA during the electrocoagulation process were primarily due to the fact that the hydroxide flocs generated in-situ were different in the presence of diverse cathodes and anions. We firstly demonstrated that Zn0.70Al0.30(OH)2(CO3)0.15·xH2O and ZnO generated in-situ in the electrocoagulation process (except for CO3(2-)/HCO3(-)) using zinc anode and aluminum/stainless steel rod cathode governed the sorption of PFOA. The adsorbent hydroxide flocs in-situ generated in the presence of Cl(-) could effectively remove PFOA from aqueous solution containing CO3(2-)/HCO3(-) anion at the initial hydroxide flocs concentration of 2000mgL(-1). These results provided an effective and alternative method to remove PFOA from aqueous solution containing CO3(2-)/HCO3(-) anion.
Collapse
Affiliation(s)
- Yujuan Wang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Hui Lin
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Fangyuan Jin
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Junfeng Niu
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China.
| | - Jinbo Zhao
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Ying Bi
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Ying Li
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China
| |
Collapse
|
41
|
Vidal J, Villegas L, Peralta-Hernández JM, Salazar González R. Removal of Acid Black 194 dye from water by electrocoagulation with aluminum anode. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2016; 51:289-296. [PMID: 26745322 DOI: 10.1080/10934529.2015.1109385] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Application of an electrocoagulation process (EC) for the elimination of AB194 textile dye from synthetic and textile wastewater (effluent) contaminated with AB194 dye, was carried out using aluminum anodes at two different initial pH values. Tafel studies in the presence and absence of the dye were performed. The aluminum species formed during the electrolysis were quantified by atomic absorption, and the flocs formed in the process were analyzed by HPLC-MS. Complete removal of AB194 from 1.0 L of solution was achieved applying low densities current at initial pH values of 4.0 and 8.0. The removal of AB194 by EC was possible with a short electrolysis time, removing practically 100% of the total organic carbon content and chemical oxygen demand. The final result was completely discolored water lacking dye and organic matter. An effluent contaminated with 126 mg L(-1) AB194 dye from a Chilean textile industry was also treated by EC under optimized experimental conditions, yielding discolored water and considerably decreasing the presence of organic compounds (dye + dyeing additives), with very low concentrations of dissolved Al(3+). Analysis of flocs showed the presence of the original dye without changes in its chemical structure.
Collapse
Affiliation(s)
- Jorge Vidal
- a Department of Materials Chemistry, Laboratory of Environmental Electrochemistry, LEQMA, Faculty of Chemistry and Biology , Santiago , Chile
| | - Loreto Villegas
- b Department of Environmental Sciences , Faculty of Chemistry and Biology, Santiago, University of Santiago of Chile, USACH , Correo , Santiago , Chile
| | - Juan M Peralta-Hernández
- c University of Guanajuato, Division of Natural and Exact Sciences , Department of Chemistry , Guanajuato , México
| | - Ricardo Salazar González
- a Department of Materials Chemistry, Laboratory of Environmental Electrochemistry, LEQMA, Faculty of Chemistry and Biology , Santiago , Chile
| |
Collapse
|
42
|
Sari MA, Chellam S. Surface water nanofiltration incorporating (electro) coagulation–microfiltration pretreatment: Fouling control and membrane characterization. J Memb Sci 2013. [DOI: 10.1016/j.memsci.2013.02.050] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|