Topic Editors

College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi’an 710021, China

Advanced Oxidation Processes for Wastewater Purification

Abstract submission deadline
30 July 2024
Manuscript submission deadline
30 September 2024
Viewed by
16610

Topic Information

Dear Colleagues,

Many emerging environmental pollutants, such as antibiotics, organic dyes, pesticides, heavy metal ions, etc., are discharged into water bodies every day. This has led to a growing water environment crisis. Water scarcity has posed challenges to human society. A variety of emerging water purification and treatment technologies, such as membrane filtration, adsorption, chemical oxidation, catalytic degradation, biotechnology, etc., have been developed to efficiently remove these pollutants. As an efficient and green chemical oxidation technology, advanced oxidation processes (AOPs) basing on the production of non-selective hydroxyl radicals have the benefits of being highly efficient, environmentally-friendly, and cost-efficient, and they take place in mild conditions, involve rapid reactions, and are simple to conduct. Therefore, this technology has attracted attentions of many researchers and been applied in the treatment of various wastewaters. AOPs include Fenton oxidation, ozone oxidation, electrochemical oxidation, photocatalysis, photolysis, etc. This Special Issue on “Advanced Oxidation Processes for Wastewater Purification” focuses on the latest novel development of AOPs for wastewater treatment. This Special Issue publishes new research papers, reviews, case reports, conference papers, etc.

Dr. Ying Zhang
Dr. Fangke Yu
Topic Editors

Keywords

  • advanced oxidation processes
  • wastewater treatment
  • AOPs
  • photocatalytic oxidation
  • catalytic oxidation
  • acoustic chemical oxidation
  • ozone oxidation
  • electrochemical oxidation
  • Fenton oxidation

Participating Journals

Journal Name Impact Factor CiteScore Launched Year First Decision (median) APC
Catalysts
catalysts
3.8 6.8 2011 12.9 Days CHF 2700 Submit
Molecules
molecules
4.2 7.4 1996 15.1 Days CHF 2700 Submit
Processes
processes
2.8 5.1 2013 14.4 Days CHF 2400 Submit
Sustainability
sustainability
3.3 6.8 2009 20 Days CHF 2400 Submit
Water
water
3.0 5.8 2009 16.5 Days CHF 2600 Submit
Nanomaterials
nanomaterials
4.4 8.5 2010 13.8 Days CHF 2900 Submit
Separations
separations
2.5 3.0 2014 12.4 Days CHF 2600 Submit

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Published Papers (13 papers)

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20 pages, 3105 KiB  
Article
Preparation of Bimetallic CoFe@CSC-700 Carbonated Microspheres and Activated Peroxymonosulfate for Degradation of Levofloxacin
by Tongke Hu, Yazhen Chen, Xiaolan Guo, Yongjun Peng and Jianhua Cheng
Water 2024, 16(13), 1818; https://doi.org/10.3390/w16131818 - 26 Jun 2024
Viewed by 822
Abstract
The exploration of efficient, low-leaching, and recyclable transition-metal-based catalysts is of great importance for the removal of pollutants from peroxymonosulfate (PMS) in water purification processes. In this study, a bimetallic CoFe@CSC-700 composite was prepared by an alkaline gel pyrolysis reduction method using chitosan [...] Read more.
The exploration of efficient, low-leaching, and recyclable transition-metal-based catalysts is of great importance for the removal of pollutants from peroxymonosulfate (PMS) in water purification processes. In this study, a bimetallic CoFe@CSC-700 composite was prepared by an alkaline gel pyrolysis reduction method using chitosan as a forming agent and applied to activate PMS to degrade levofloxacin (LEV). The leaching concentration of both cobalt and iron ions in the CoFe@CSC-700 catalyst was reduced by about 8-fold compared to the monometallic composite pellet catalyst. In addition, the removal efficiency of the CoFe@CSC-700 catalyst can still reach 90% after five cycles, showing good recyclability, recoverability and stability. Both free radical pathways (SO4·, ·OH, and ·O2) and non-free radical pathways (1O2) were detected in the oxidation reaction, with free radical pathways as the main contributor. The possible degradation pathways of LEV were proposed by LC-MS tests. Overall, this study provides new insights into the construction of efficient and stable PMS catalysts for wastewater treatment. Full article
(This article belongs to the Topic Advanced Oxidation Processes for Wastewater Purification)
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17 pages, 5033 KiB  
Review
Performance of Traditional and Emerging Water-Treatment Technologies in the Removal of Tetracycline Antibiotics
by Fanjin Wang, Ziyi Wang, Yue Zhao and Jian Zhang
Catalysts 2024, 14(4), 269; https://doi.org/10.3390/catal14040269 - 17 Apr 2024
Viewed by 1104
Abstract
Tetracycline antibiotics are widely used in human medical treatment, control of animal disease, and agricultural feed because of their broad spectrum of action, high efficiency, and low cost. The excessive use of antibiotics and arbitrary discharge of antibiotic wastewater have become increasingly serious [...] Read more.
Tetracycline antibiotics are widely used in human medical treatment, control of animal disease, and agricultural feed because of their broad spectrum of action, high efficiency, and low cost. The excessive use of antibiotics and arbitrary discharge of antibiotic wastewater have become increasingly serious problems, and the current sewage-treatment process is not ideal for treating water contaminated with tetracycline antibiotics, leading to increasingly prominent antibiotic pollution in water and the imminent need for its removal. In order to understand the necessity of removing tetracycline antibiotics from the water environment, this paper first expounds on their source, harms, and pollution status in oceans and in surface water, groundwater, wastewater, and drinking water. It next introduces the research status of conventional treatment methods such as adsorption methods, biological methods, and physical and chemical methods, then introduces new treatment methods such as advanced oxidation methods and comprehensive treatment technology in sewage plants. The degradation effects, mechanisms of action, and challenges of these methods were summarized. The advantages and disadvantages of each treatment technology are compared. Finally, potential future processing technologies are discussed. Full article
(This article belongs to the Topic Advanced Oxidation Processes for Wastewater Purification)
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42 pages, 7354 KiB  
Review
An Overview of Environmental Catalysis Mediated by Hydrogen Peroxide
by Monica Rigoletto, Enzo Laurenti and Maria Laura Tummino
Catalysts 2024, 14(4), 267; https://doi.org/10.3390/catal14040267 - 17 Apr 2024
Viewed by 1368
Abstract
The use of hydrogen peroxide (produced in situ or ex situ) as the main agent in oxidative processes of environmental pollutant removal is widely studied. The degradation of water pollutants, such as dyes, pharmaceuticals, cosmetics, petroleum derivatives, and even pathogens, has been successfully [...] Read more.
The use of hydrogen peroxide (produced in situ or ex situ) as the main agent in oxidative processes of environmental pollutant removal is widely studied. The degradation of water pollutants, such as dyes, pharmaceuticals, cosmetics, petroleum derivatives, and even pathogens, has been successfully obtained by different techniques. This review gives an overview of the more recent methods developed to apply oxidative processes mediated by H2O2 and other reactive oxygen species (ROS) in environmental catalysis, with particular attention to the strategies (Fenton-like and Bio-Fenton, photo- and electro-catalysis) and the materials employed. A wide discussion about the characteristics of the materials specifically studied for hydrogen peroxide activation, as well as about their chemical composition and morphology, was carried out. Moreover, recent interesting methods for the generation and use of hydrogen peroxide by enzymes were also presented and their efficiency and applicability compared with the Fenton and electro-Fenton methods discussed above. The use of Bio-Fenton and bi-enzymatic methods for the in situ generation of ROS seems to be attractive and scalable, although not yet applied in full-scale plants. A critical discussion about the feasibility, criticalities, and perspectives of all the methods considered completes this review. Full article
(This article belongs to the Topic Advanced Oxidation Processes for Wastewater Purification)
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23 pages, 7253 KiB  
Article
Insight into the Catalytic Performance of a Zinc-Pillared Curcumin/Bentonite Composite for Enhanced Oxidation of Ibuprofen Residuals into Environmental Products: The Pathway and Toxicity
by Sarah I. Othman, Marwa H. Shemy, Haifa E. Alfassam, Haifa A. Alqhtani, Ahmed A. Allam, Mostafa R. Abukhadra and Stefano Bellucci
Catalysts 2024, 14(2), 129; https://doi.org/10.3390/catal14020129 - 7 Feb 2024
Cited by 1 | Viewed by 1303
Abstract
Environmental organo bentonite synthesis using curcumin-derived chemicals is used as catalyst support for zinc with a Zn-pillaring structure (Zn@CU/BEN). The obtained composite was assessed as an affordable, highly effective, and multifunctional photocatalyst for enhanced oxidation of ibuprofen (IBU) residuals in water supplies. The [...] Read more.
Environmental organo bentonite synthesis using curcumin-derived chemicals is used as catalyst support for zinc with a Zn-pillaring structure (Zn@CU/BEN). The obtained composite was assessed as an affordable, highly effective, and multifunctional photocatalyst for enhanced oxidation of ibuprofen (IBU) residuals in water supplies. The Zn@CU/BEN composite (0.4 g/L) displayed significant catalytic activities, resulting in the complete oxidation of IBU (25 mg/L) after 80 min. Then, the complete mineralization based on the full elimination of TOC content was recognized after 160 min, with significant indications about the formed intermediates. The identified intermediates, together with the identification of hydroxyl radicals as the essential oxidizing agent, declared an oxidation pathway of IBU over Zn@CU/BEN that involved three steps: hydroxylation, decarboxylation/demethylation, and ring-opening processes. The toxic properties of raw pollutants as well as the oxidizing product at different durations were assessed based on the cell viability results of kidney (HEK293T) and liver (HepG2) cell lines. The partially oxidized sample in the initial duration displayed a higher toxicity impact than the raw IBU. However, the treated sample after 160 min reflected high biosafety and non-toxic properties (cell viability > 97%). The synergetic impact of bentonite and bentonite organo-modified by curcumin extract reflects enhancements in the adsorption as well as the oxidation performance of pillared zinc as a catalyst. Full article
(This article belongs to the Topic Advanced Oxidation Processes for Wastewater Purification)
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22 pages, 6018 KiB  
Article
Synergism of Artificial Intelligence and Techno-Economic for Sustainable Treatment of Methylene Blue Dye-Containing Wastewater by Photocatalysis
by Khumbolake Faith Ngulube, Amal Abdelhaleem, Manabu Fujii and Mahmoud Nasr
Sustainability 2024, 16(2), 529; https://doi.org/10.3390/su16020529 - 8 Jan 2024
Cited by 3 | Viewed by 1432
Abstract
Recently, removing dyes from wastewater by photocatalysis has been extensively studied by several researchers. However, there exists a research gap in optimizing the photocatalytic process parameters using artificial intelligence to maintain the associated techno-economic feasibility. Hence, this investigation attempts to optimize the photocatalytic [...] Read more.
Recently, removing dyes from wastewater by photocatalysis has been extensively studied by several researchers. However, there exists a research gap in optimizing the photocatalytic process parameters using artificial intelligence to maintain the associated techno-economic feasibility. Hence, this investigation attempts to optimize the photocatalytic degradation of methylene blue (MB) dye using an artificial neural network (ANN) model to minimize the capital and running costs, which is beneficial for industrial applications. A ZnO/MgO photocatalyst was synthesized, showing an energy band gap of 2.96 eV, crystallinity index of 71.92%, pore volume of 0.529 cm3/g, surface area of 30.536 m2/g, and multiple surface functional groups. An ANN model, with a 4-8-1 topology, trainlm training function, and feed-forward back-propagation algorithm, succeeded in predicting the MB removal efficiency (R2 = 0.946 and mean squared error = 11.2). The ANN-based optimized condition depicted that over 99% of MB could be removed under C0 = 16.42 mg/L, pH = 9.95, and catalyst dosage = 905 mg/L within 174 min. This optimum condition corresponded to a treatment cost of USD 8.52/m3 cheaper than the price estimated from the unoptimized photocatalytic system by ≈7%. The study outputs revealed positive correlations with the sustainable development goals accompanied by pollution reduction, human health protection, and aquatic species conservation. Full article
(This article belongs to the Topic Advanced Oxidation Processes for Wastewater Purification)
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18 pages, 7358 KiB  
Article
Novel Fenton-like Catalyst HKUST-1(Cu)/MoS2-3-C with Non-Equilibrium-State Surface for Selective Degradation of Phenolic Contaminants: Synergistic Effects of σ-Cu-Ligand and ≡Mo–OOSO3 Complex
by Xiaoze Yin, Huaqin Yin, Renjie Wang, Jinnan Wang and Aimin Li
Water 2024, 16(1), 121; https://doi.org/10.3390/w16010121 - 28 Dec 2023
Viewed by 1099
Abstract
Novel Fenton-like catalyst HKUST-1(Cu)/MoS2-3-C with a non-equilibrium-state surface was constructed for selective degradation of phenolic contaminants. Electron-polarized distribution facilitated the formation of σ-Cu-ligand between electron-poor Cu centre and phenolic compounds, which not only enhanced radicals generation but also accelerated the Cu(I)/Cu(II) [...] Read more.
Novel Fenton-like catalyst HKUST-1(Cu)/MoS2-3-C with a non-equilibrium-state surface was constructed for selective degradation of phenolic contaminants. Electron-polarized distribution facilitated the formation of σ-Cu-ligand between electron-poor Cu centre and phenolic compounds, which not only enhanced radicals generation but also accelerated the Cu(I)/Cu(II) redox. Meanwhile, ≡Mo–OOSO3 complexes formed by the electron-rich Mo centre and peroxymonosulfate (PMS), could directly oxidize phenolic contaminants with the generation of SO4•−. The radical quenching experiments and EPR tests indicated that both SO4•− and OH played a dominant role in the reaction. Additionally, O2 could be reduced to O2•− by OVs and subsequently converted into 1O2 over the Mo centre. DFT calculation, FT-IR, and in situ Raman spectra analysis results demonstrated that phenolic compounds and PMS were respectively adsorbed by electron-poor Cu centre and electron-rich Mo centre, favouring the electrons transfer from phenolic contaminants to Mo centre for PMS activation. With synergistic effects of σ-Cu-ligand and ≡Mo–OOSO3 complexes, HKUST-1(Cu)/MoS2-3-C achieved a high degradation rate of phenolic contaminants and utilization efficiency of PMS. Full article
(This article belongs to the Topic Advanced Oxidation Processes for Wastewater Purification)
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14 pages, 4655 KiB  
Article
In Situ Synthesis of Bi2S3/BiFeO3 Nanoflower Hybrid Photocatalyst for Enhanced Photocatalytic Degradation of Organic Pollutants
by Rentao Zhou, Xinman Tu, Peng Zheng, Li Zhang and Zhenxing Zeng
Molecules 2023, 28(24), 8007; https://doi.org/10.3390/molecules28248007 - 8 Dec 2023
Viewed by 923
Abstract
Photocatalytic degradation of Malachite Green oxalate (MG) in a water body is of significant importance to our health protection, as it could cause various serious diseases. However the photocatalytic activity of most catalysts is still unsatisfactory, due to the poor reactive oxygen species [...] Read more.
Photocatalytic degradation of Malachite Green oxalate (MG) in a water body is of significant importance to our health protection, as it could cause various serious diseases. However the photocatalytic activity of most catalysts is still unsatisfactory, due to the poor reactive oxygen species production as a result of sluggish charge separation. Here, innovative nanoflower-shaped Bi2S3/BiFeO3 heterojunctions are prepared via a facile sol–gel method, exhibiting an enhanced reactive oxygen species generation, which leads to the excellent photocatalytic performance toward MG degradation. We verify that interfacing BiFeO3 with Bi2S3 could form a fine junction and offers a built-in field to speed up charge separation at the junction area; as a result, this shows much higher charge separation efficiency. By virtue of the aforementioned advantages, the as-prepared Bi2S3/BiFeO3 heterojunctions exhibit excellent photocatalytic performance toward MG degradation, where more than 99% of MG is removed within 2 h of photocatalysis. The innovative design of nanoflower-like Bi2S3/BiFeO3 heterojunctions may offer new viewpoints in designing highly efficient photocatalysts for environmentally related applications. Full article
(This article belongs to the Topic Advanced Oxidation Processes for Wastewater Purification)
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15 pages, 4299 KiB  
Article
S-Scheme WO3/SnIn4S8 Heterojunction for Water Purification: Enhanced Photocatalytic Performance and Mechanism
by Pingfan Xu, Runqiu Zhang, Jiarong Gong, Yaofa Luo, Yihua Zhuang and Peikun Zhang
Catalysts 2023, 13(11), 1450; https://doi.org/10.3390/catal13111450 - 20 Nov 2023
Viewed by 1262
Abstract
Photocatalysis is a promising technology for removing micropollutants in water. However, developing efficient and stable catalysts remains a challenge. In this work, a novel step-scheme (S-scheme) heterojunction of WO3/SnIn4S8 (WSI) was constructed through the combined process of in [...] Read more.
Photocatalysis is a promising technology for removing micropollutants in water. However, developing efficient and stable catalysts remains a challenge. In this work, a novel step-scheme (S-scheme) heterojunction of WO3/SnIn4S8 (WSI) was constructed through the combined process of in situ precipitation with hydrothermal synthesis to simultaneously realize photocatalytic degradation of bisphenol A(BPA) and reduction of Cr(VI) in contaminated water. Results showed that the WSI S-scheme heterojuction has a synergistic effect for the removal of BPA and Cr(VI). An optimum case of the WSI-12% heterojunction exhibited the highest photocatalytic efficiency in the degradation of BPA under visible light, which is ca. 2.5 and 3.8 times more than the pure WO3 and SIS, respectively. The enhanced photocatalytic activity is attributed to the formation of the WSI S-scheme heterojunctions which facilitate the spatial separation of charge carriers and preserve strong photoredox ability. Further, the S-scheme mechanism of enhanced photocatalysis was examined by the radical-trapping experiment and ESR, and superoxide and hydroxyl radicals were determined to be the major reactive oxygen species responsible for BPA degradation and Cr(VI) reduction by WSI. This work provides a novel strategy for tailoring high-performance S-scheme heterojunctions and shows the promising application in purifying wastewater with complex pollutants. Full article
(This article belongs to the Topic Advanced Oxidation Processes for Wastewater Purification)
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23 pages, 8807 KiB  
Article
The Addition of Anthocyanin as a Sensitizer for TiO2 Nanotubes in a Combined Process of Electrocoagulation and Photocatalysis for Methylene Blue Removal
by Indar Kustiningsih, Hendrini Pujiastuti, Denni Kartika Sari, Agus Rochmat and Slamet
Sustainability 2023, 15(21), 15384; https://doi.org/10.3390/su152115384 - 27 Oct 2023
Viewed by 1050
Abstract
Photocatalysis with TiO2 semiconductors is one of several potential methods for removing Methylene Blue (MB) that is environmentally friendly, relatively cheap, and effective. The capability of TiO2 photocatalysts for degrading MB can be improved by modifying the morphology of TiO2 [...] Read more.
Photocatalysis with TiO2 semiconductors is one of several potential methods for removing Methylene Blue (MB) that is environmentally friendly, relatively cheap, and effective. The capability of TiO2 photocatalysts for degrading MB can be improved by modifying the morphology of TiO2 into nanotubes and adding anthocyanin sensitizers. The objective of this study was to investigate the effect of anthocyanin sensitizer addition for TiO2 nanotubes on MB removal using a combined process of electrocoagulation and photocatalysis. TiO2 nanotubes were prepared through an anodization method with a glycerol electrolyte containing NH4F of 0.5% w/v and water of 25% v/v. The cathode and anode used in the electrocoagulation process were 316 stainless steel and aluminum, respectively. The characteristics of the resulting TiO2 nanotubes were analyzed using SEM-EDX, UV–Vis DRS, and XRD analyses. The results showed that the electrocoagulation at a pH of 10 and a voltage of 50 volts resulted in an MB removal efficiency of 57.88%. In the photocatalysis process, sensitizer addition can increase the MB removal efficiency from 19.71% to 29.06%. Furthermore, a combined process of electrocoagulation and photocatalysis without and with sensitizer addition resulted in MB removal efficiencies of 59.66% and 64.30%, respectively. Full article
(This article belongs to the Topic Advanced Oxidation Processes for Wastewater Purification)
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17 pages, 3274 KiB  
Article
Study of the Process of Electrochemical Oxidation of Active Pharmaceutical Substances on the Example of Nitrofurazone ((2E)-2-[(5-Nitro-2-furyl)methylene]hydrazine Carboxamide)
by Vitalyi Vladimirovich Kuznetsov, Natalya Andreevna Ivantsova, Evgenii Nikolaevich Kuzin, Andrey Vladimirovich Pirogov, Yaroslav Olegovich Mezhuev, Elena Alexeevna Filatova and Yulia Michailovna Averina
Water 2023, 15(19), 3370; https://doi.org/10.3390/w15193370 - 26 Sep 2023
Cited by 1 | Viewed by 1183
Abstract
The effective mineralization of nitrofurazone (10–100 mg L−1) was performed in aqueous solutions in the presence of chloride ions by electrochemical treatment. The destruction of the organic pollutant molecules was due to their interaction with active oxygen- and chlorine-containing species forming [...] Read more.
The effective mineralization of nitrofurazone (10–100 mg L−1) was performed in aqueous solutions in the presence of chloride ions by electrochemical treatment. The destruction of the organic pollutant molecules was due to their interaction with active oxygen- and chlorine-containing species forming at the inert anode (Pt/Ti or BDD) during electrolysis. Measurements of nitrofurazone concentration, chemical oxygen demand (COD) and total organic carbon (TOC) were used to estimate the removal efficiency of the pollutant. Both the pollutant oxidation rate and the degree of its mineralization were higher for the BDD anode due to the higher anode potentials on it in the course of electrolysis, which provides a high rate of active oxidizer species generation. As a result, practically full nitrofurazone molecule destruction (>99%) was achieved in 30 min at an anodic current density of 0.1 A cm−2, a volume current density of 1.33 A L−1 and pH 2 using BDD anodes. On the other hand, the nitrafurazone degradation efficiency was about 95% for Pt/Ti anodes under the same conditions. Additionally, byproducts of nitrofurazone electrooxidation were investigated by means of liquid chromato-mass-spectrometry (LC/MS). It was found that the initial decolorization of nitrofurazone solution, which occurs during the first 5 min of electrolysis, is due to the formation of a dichloro derivative of nitrofurazone, which causes the destruction of the π−conjugated bond system. Further electrolysis resulted in the almost complete destruction of the dichloro derivative within 30 min of electrochemical treatment. Full article
(This article belongs to the Topic Advanced Oxidation Processes for Wastewater Purification)
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24 pages, 6748 KiB  
Review
Metal-Based Electrocatalysts for Selective Electrochemical Nitrogen Reduction to Ammonia
by Yi-Zhen Zhang, Peng-Hui Li, Yi-Nuo Ren, Yun He, Cheng-Xu Zhang, Jue Hu, Xiao-Qiang Cao and Michael K. H. Leung
Nanomaterials 2023, 13(18), 2580; https://doi.org/10.3390/nano13182580 - 18 Sep 2023
Cited by 1 | Viewed by 1698
Abstract
Ammonia (NH3) plays a significant role in the manufacture of fertilizers, nitrogen-containing chemical production, and hydrogen storage. The electrochemical nitrogen reduction reaction (e-NRR) is an attractive prospect for achieving clean and sustainable NH3 production, under mild conditions driven by renewable [...] Read more.
Ammonia (NH3) plays a significant role in the manufacture of fertilizers, nitrogen-containing chemical production, and hydrogen storage. The electrochemical nitrogen reduction reaction (e-NRR) is an attractive prospect for achieving clean and sustainable NH3 production, under mild conditions driven by renewable energy. The sluggish cleavage of N≡N bonds and poor selectivity of e-NRR are the primary challenges for e-NRR, over the competitive hydrogen evolution reaction (HER). The rational design of e-NRR electrocatalysts is of vital significance and should be based on a thorough understanding of the structure–activity relationship and mechanism. Among the various explored e-NRR catalysts, metal-based electrocatalysts have drawn increasing attention due to their remarkable performances. This review highlighted the recent progress and developments in metal-based electrocatalysts for e-NRR. Different kinds of metal-based electrocatalysts used in NH3 synthesis (including noble-metal-based catalysts, non-noble-metal-based catalysts, and metal compound catalysts) were introduced. The theoretical screening and the experimental practice of rational metal-based electrocatalyst design with different strategies were systematically summarized. Additionally, the structure–function relationship to improve the NH3 yield was evaluated. Finally, current challenges and perspectives of this burgeoning area were provided. The objective of this review is to provide a comprehensive understanding of metal-based e-NRR electrocatalysts with a focus on enhancing their efficiency in the future. Full article
(This article belongs to the Topic Advanced Oxidation Processes for Wastewater Purification)
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8 pages, 2353 KiB  
Article
ZIF-67(Co)-Loaded Filter Paper for In Situ Catalytic Degradation of Bisphenol A in Water
by Zhimin Cai, Yutao Luo and Lu Gan
Separations 2022, 9(11), 340; https://doi.org/10.3390/separations9110340 - 3 Nov 2022
Cited by 2 | Viewed by 1443
Abstract
Herein, we loaded cobalt-based zeolite imidazolate frameworks, ZIF-67 (Co), onto commercial filter paper to prepare catalytic filter paper (ZFP) for the in situ degradation of bisphenol A (BPA) in water by activating peroxymonosulfate. The results showed that ZIF-67 (Co) was densely and uniformly [...] Read more.
Herein, we loaded cobalt-based zeolite imidazolate frameworks, ZIF-67 (Co), onto commercial filter paper to prepare catalytic filter paper (ZFP) for the in situ degradation of bisphenol A (BPA) in water by activating peroxymonosulfate. The results showed that ZIF-67 (Co) was densely and uniformly distributed on the surface of the filter paper. The prepared ZFP could effectively degrade BPA in situ through a gravity-driven filtration process. Specifically, when the flow rate of the BPA solution passing through ZFP was lower than 10 mL/min, 0.02 mM of BPA could be completely degraded by ZFP. Furthermore, ZFP showed promising water matrix adaptability, which could provide promising BPA degradation efficiency in a wide pH range or in the existence of multiple anions. The scavenging tests demonstrated that both sulfate radical and hydroxyl radical were generated for BPA degradation, in which hydroxyl radical was the dominant active species. The ZFP also exhibited promising long-time use stability with a high mineralization rate. This study provides a novel method to prepare high-efficient catalyst paper for the in situ organic pollutant removal in water media via a prompt filtration process. Full article
(This article belongs to the Topic Advanced Oxidation Processes for Wastewater Purification)
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16 pages, 3022 KiB  
Article
Effect of Anions and Cations on Tartrazine Removal by the Zero-Valent Iron/Peroxymonosulfate Process: Efficiency and Major Radicals
by Wenqi You, Liang Liu, Junjie Xu, Tao Jin, Lichun Fu and Yuwei Pan
Catalysts 2022, 12(10), 1114; https://doi.org/10.3390/catal12101114 - 26 Sep 2022
Cited by 12 | Viewed by 1304
Abstract
Zero-valent iron/peroxymonosulfate (Fe0/PMS) has been considered as a promising approach for wastewater treatment. Anions and cations are widely present in wastewater and have significant effects on the performance of the Fe0/PMS system for wastewater treatment. Thus, in the present [...] Read more.
Zero-valent iron/peroxymonosulfate (Fe0/PMS) has been considered as a promising approach for wastewater treatment. Anions and cations are widely present in wastewater and have significant effects on the performance of the Fe0/PMS system for wastewater treatment. Thus, in the present study, tartrazine was selected as the target model; SO42−, NO3, HCO3, and Cl were selected as representative anions and Ca2+, Cu2+, Mg2+, and Mn2+ were chosen as representative cations. The effect of these anions and cations on tartrazine removal and major radicals in the Fe0/PMS were systematically investigated. The presence of a certain concentration of SO42− and Cl had positive, NO3 had negative, and HCO3 had negligible effects on tartrazine removal in the Fe0/PMS system. SO42− and HCO3 had a small effect on the contribution proportion of reduction, SO4•− and OH; a certain concentration of Cl could enhance the contribution proportion of OH; and NO3 would decrease the contribution proportion of SO4•− and OH. A certain concentration of each of Ca2+, Cu2+, Mg2+, and Mn2+ could enhance the tartrazine removal in the Fe0/PMS system. Ca2+, Cu2+, and Mg2+ had no effect of the contribution of reduction, SO4•− and OH, while a certain concentration of Mn2+ could enhance the contribution proportion of SO4•−. These results can provide some references for the Fe0/PMS system to treat actual wastewater containing anions and cations. Full article
(This article belongs to the Topic Advanced Oxidation Processes for Wastewater Purification)
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