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Mortazavi M, Garg S, Waite TD. Kinetic modelling assisted balancing of organic pollutant removal and bromate formation during peroxone treatment of bromide-containing waters. JOURNAL OF HAZARDOUS MATERIALS 2024; 468:133736. [PMID: 38377900 DOI: 10.1016/j.jhazmat.2024.133736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 01/25/2024] [Accepted: 02/04/2024] [Indexed: 02/22/2024]
Abstract
The peroxone process (O3/H2O2) is reported to be a more effective process than the ozonation process due to an increased rate of generation of hydroxyl radicals (•OH) and inhibition of bromate (BrO3-) formation which is otherwise formed on ozonation of bromide containing waters. However, the trade-off between the H2O2 dosage required for minimization of BrO3- formation and effective pollutant removal has not been clearly delineated. In this study, employing experimental investigations as well as chemical modelling, we show that the concentration of H2O2 required to achieve maximum pollutant removal may not be the same as that required for minimization of BrO3- formation. At the H2O2 dosage required to minimize BrO3- formation (<10 µg/L), only pollutants with high to moderate reactivity towards O3 and •OH are effectively removed. For pollutants with low reactivity towards O3/•OH, high O3 (O3:DOC>>1 g/g) and high H2O2 dosages (O3:H2O2 ∼1 (g/g)) are required for minimizing BrO3- formation along with effective pollutant removal which may result in a very high residual of H2O2 in the effluent, causing secondary pollution. On balance, we conclude that the peroxone process is not effective for the removal of low reactivity micropollutants if minimization of BrO3- formation is also required.
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Affiliation(s)
- Mahshid Mortazavi
- UNSW Water Research Centre, School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Shikha Garg
- UNSW Water Research Centre, School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
| | - T David Waite
- UNSW Water Research Centre, School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW 2052, Australia.
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2
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Chien KC, Maity S, Hiramatsu H. Origin of unique hyper-Raman signals of trifluoroethanol. Phys Chem Chem Phys 2023; 25:27949-27952. [PMID: 37830311 DOI: 10.1039/d3cp03481j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
We report the hyper-Raman (HR) spectrum of trifluoroethanol, excited with 532 nm light, in an aqueous solution at basic pH. The HR spectrum exhibits a distinct spectral pattern that diverges entirely from the infrared and Raman spectra of trifluoroethanol. This observed unique HR signal was attributed to the products of photoinduced radical reactions in the aqueous solution. This result exemplifies the exceptional capabilities of HR spectroscopy based on resonance conditions.
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Affiliation(s)
- Kai-Chin Chien
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu, 30010, Taiwan.
| | - Surajit Maity
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu, 30010, Taiwan.
| | - Hirotsugu Hiramatsu
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu, 30010, Taiwan.
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3
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Gier Della Rocca D, Santos e Sousa FA, Domingos Ardisson J, Peralta RA, Rodríguez-Castellón E, Peralta Muniz Moreira RDF. Magnetic mining waste based-geopolymers applied to catalytic reactions with ozone. Heliyon 2023; 9:e17097. [PMID: 37484270 PMCID: PMC10361246 DOI: 10.1016/j.heliyon.2023.e17097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 05/31/2023] [Accepted: 06/07/2023] [Indexed: 07/25/2023] Open
Abstract
The demand for sustainable and low-cost materials for wastewater treatment is increasing considerably. In this scenario, geopolymers have gained great interest, due to their good mechanical properties, their ability to be produced from industrial waste and their adsorbent or catalytic properties. In this study, novel magnetic mining waste based-geopolymers were produced by incorporating a residue from phosphate waste rocks, which were extensively characterized (XRD, TGA/DTA, SEM, BET, XRF, FTIR, Mössbauer, ss-NMR and XPS). The materials produced showed formation of a dense framework, even with 75% incorporation of the residue. The iron oxides and their magnetic properties remained unchanged, and their application in advanced oxidation reactions were evaluated, in particular, as catalysts in ozonation reactions. All of the geopolymers presented catalytic activity in the ozonation reaction, with catalytic ozone decomposition values of up to 2.98 min-1, which is 99 times greater than non-catalyzed reactions. Moreover, the reuse (performed in three cycles) and hot filtration-like experiments demonstrated, respectively, the regenerability and heterogeneous catalytic properties of the produced materials, showcasing the potential of these waste materials for catalytic geopolymer production. demonstrating the potential of this waste to produce catalytic geopolymers.
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Affiliation(s)
- Daniela Gier Della Rocca
- Laboratory of Energy and Environment (LEMA), Department of Chemical and Food Engineering, Federal University of Santa Catarina (UFSC), 88040-900 Florianópolis, SC, Brazil
| | - Flávio Augusto Santos e Sousa
- Laboratory of Energy and Environment (LEMA), Department of Chemical and Food Engineering, Federal University of Santa Catarina (UFSC), 88040-900 Florianópolis, SC, Brazil
| | - José Domingos Ardisson
- Laboratory of Applied Physics, Center for the Development of Nuclear Technology, Federal University of Minas Gerais, 30123-970, Belo Horizonte, MG, Brazil
| | - Rosely Aparecida Peralta
- Laboratory of Bioinorganic and Crystallography Laboratory (LABINC), Department of Chemistry, Federal University of Santa Catarina (UFSC), 88040-900 Florianópolis, SC, Brazil
| | | | - Regina de Fátima Peralta Muniz Moreira
- Laboratory of Energy and Environment (LEMA), Department of Chemical and Food Engineering, Federal University of Santa Catarina (UFSC), 88040-900 Florianópolis, SC, Brazil
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Mortazavi M, Garg S, Waite TD. Kinetic Modeling-Assisted Optimization of the Peroxone (O 3/H 2O 2) Water Treatment Process. Ind Eng Chem Res 2023. [DOI: 10.1021/acs.iecr.3c00020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Affiliation(s)
- Mahshid Mortazavi
- UNSW Water Research Centre, School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Shikha Garg
- UNSW Water Research Centre, School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
| | - T. David Waite
- UNSW Water Research Centre, School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
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Bifunctional CePO 4/CeO 2 nanocomposite as a promising heterogeneous catalyst for the enhancement of the ozonation recovery effect in the presence of chloride ions. Sci Rep 2022; 12:9043. [PMID: 35641621 PMCID: PMC9156760 DOI: 10.1038/s41598-022-13069-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 05/20/2022] [Indexed: 11/08/2022] Open
Abstract
The degradation of organics through ozonation is strongly reduced by chloride ions. Although the efficiency of such processes can be recovered in the presence of homogeneous phosphates, the addition of these chemicals to water is problematic because of the generation of secondary wastes. Phosphates are known as one of the most important biogens responsible for the eutrophication of rivers and lakes. Thus, their worldwide application should be limited. The main goal of this work was to characterize the performance of solid-state cerium(III) phosphate (CePO4), cerium dioxide (CeO2), and bifunctional CePO4/CeO2 nanocomposite as substitutes for homogeneous phosphates during the ozonation of benzoic acid (BA) in the presence of chlorides. All solid-state samples used in this study were synthesized by facile hydrothermal method and thoroughly characterized. It was documented that heterogeneous CePO4 showed significantly better ozonation recovery effect than homogeneous phosphates. It was also established that the process efficiency could be further enhanced by using the bifunctional nanocomposite. Tests with the use of tert-butanol as a hydroxyl radical scavenger revealed that the improved ozonation efficiency in the presence of CePO4/CeO2 resulted from the action of HO• radicals which were the key reactive oxygen species responsible for the recovery of BA degradation in the presence of chlorides.
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Asghar A, Lutze HV, Tuerk J, Schmidt TC. Influence of water matrix on the degradation of organic micropollutants by ozone based processes: A review on oxidant scavenging mechanism. JOURNAL OF HAZARDOUS MATERIALS 2022; 429:128189. [PMID: 35077976 DOI: 10.1016/j.jhazmat.2021.128189] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 12/20/2021] [Accepted: 12/28/2021] [Indexed: 06/14/2023]
Abstract
The prevalence of organic micropollutants (OMPs) in aquatic environment has expedited scientific and regulatory efforts to retrofit existing wastewater treatment plants (WWTPs). The current strategy involves WWTPs upgrading with post-ozonation i.e., ozone (O3) and/or peroxone process (O3 +H2O2). Still, ozone-based degradation of OMPs faces several challenges. For example, the degradation mechanism and kinetics of OMPs could largely be affected by water matrix compounds which include inorganic ions and natural organic matter (NOM). pH also plays a decisive role in determining the reactivity of the oxidants (O3, H2O2, andHO•), stability and speciation of matrix constituents and OMPs and thus susceptibility of OMPs to the reactions with oxidants. There have been reviews discussing the impact of matrix components on the degradation of OMPs by advanced oxidation processes (AOPs). Nevertheless, a review focusing on scavenging mechanisms, formation of secondary oxidants and their scavenging effects with a particular focus on ozonation and peroxone process is lacking. Therefore, in order to broaden the knowledge on this subject, the database 'Web of Science' was searched for the studies related to the 'matrix effect on the degradation of organic micropollutants by ozone based processes' over the time period of 2004-2021. The relevant literature was thoroughly reviewed and following conclusions were made: i) chloride has inhibitory effects if it exits at higher concentrations or as free chlorine i.e. HOCl/ClO-. ii) The inhibitory effects of chloride, bromide, HOBr/OBr- and HOCl/ClO- are dominant in neutral and alkaline conditions and may result in the formation of secondary oxidants (e.g., chlorine atoms or free bromine), which in turn contribute to pollutant degradation or form undesired oxidation by-products such as BrO3-, ClO3- and halogenated organic products. ii) NOM may induce inhibitory or synergetic effects depending on the type, chemical properties and concentration of NOM. Therefore, more efforts are required to understand the importance of pH variation as well as the effects of water matrix on the reactivity of oxidants and subsequent degradation of OMPs.
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Affiliation(s)
- Anam Asghar
- Instrumental Analytical Chemistry, Faculty of Chemistry, University of Duisburg-Essen, Universitätsstr. 5, Essen, Germany.
| | - Holger V Lutze
- Department of Civil and Environmental Engineering Sciences, Technische Universität Darmstadt, Karolinenpl. 5, 64289 Darmstadt, Germany; Centre for Water and Environmental Research (ZWU), Universitätsstraße 5, 45141 Essen, Germany; IWW Water Centre, Moritzstraße 26, 45476 Mülheim an der Ruhr, Germany
| | - Jochen Tuerk
- Institut für Energie, und Umwelttechnik e. V. (IUTA, Institute of Energy and Environmental Technology), Bliersheimer Str. 58-60, 47229 Duisburg, Germany; Centre for Water and Environmental Research (ZWU), Universitätsstraße 5, 45141 Essen, Germany
| | - Torsten C Schmidt
- Instrumental Analytical Chemistry, Faculty of Chemistry, University of Duisburg-Essen, Universitätsstr. 5, Essen, Germany; Centre for Water and Environmental Research (ZWU), Universitätsstraße 5, 45141 Essen, Germany; IWW Water Centre, Moritzstraße 26, 45476 Mülheim an der Ruhr, Germany
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Oyekunle DT, Li D, Zheng L, Luo F, Wang S, Chen Z. Enhanced degradation of organic compounds through the interfacial transfer of electrons in the presence of phosphate and Nitrogen-cobalt doped graphitic carbon. J Colloid Interface Sci 2021; 607:1641-1650. [PMID: 34592551 DOI: 10.1016/j.jcis.2021.09.044] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/06/2021] [Accepted: 09/07/2021] [Indexed: 10/20/2022]
Abstract
Peroxymonosulfate (PMS) has been activated for the generation of reactive oxygen species by nitrogen-doped carbonaceous material. However, the influence of phosphate on the degradation performance has not been reported. In this study, phosphate ions accelerate PMS decomposition and degradation of target organic compounds such as carbamazepine, atrazine, sulfamethoxazole, and benzoic acid. It was revealed that the physical mixture of phosphate with Co and N doped graphitic carbon (GcN/Co) demonstrates the occurrence of P C, P N, and P O - C bonds. Essentially, the graphitic N or graphitic N P increased in the presence of phosphate. This was correlated with the lower electrical transfer resistance, improved electrical conductivity, and higher electron morbidity confirmed by different electrochemical tests. Moreover, due to the strong buffering capacity of phosphate at neutral pH, bicarbonate was used to confirm the negligible influence of pH. The presence of phosphate helps to recover the scavenging effect of Cl- but has no effect on the presence of HCO3- and CO32-. Nevertheless, GcN/Co demonstrates good reusability for three reaction cycles, however, in order to maintain a high catalytic performance phosphate needs to be replenished after each cycle.
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Affiliation(s)
- Daniel T Oyekunle
- Key laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, PR China; Department of Chemical Engineering, College of Engineering, Covenant University, Ota, Nigeria.
| | - Dan Li
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Li Zheng
- Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Fang Luo
- Key laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, PR China
| | - Songlin Wang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Zhuqi Chen
- Key laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, PR China.
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8
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Fijołek L, Świetlik J, Frankowski M. The influence of active carbon contaminants on the ozonation mechanism interpretation. Sci Rep 2021; 11:9934. [PMID: 33976325 PMCID: PMC8113541 DOI: 10.1038/s41598-021-89510-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 04/27/2021] [Indexed: 11/08/2022] Open
Abstract
In water treatment technology, activated carbons are used primarily as sorbents to remove organic impurities, mainly natural organic matter, but also as catalysts in the ozonation process. Commercially available activated carbons are usually contaminated with mineral substances, classified into two main groups: alkali metals (Ca, Na, K, Li, Mg) and multivalent metals (Al, Fe, Ti, Si). The presence of impurities on the carbon surface significantly affects the pHpzc values determined for raw and ozonated carbon as well as their acidity and alkalinity. The scale of the observed changes strongly depends on the pH of the ozonated system, which is related to the diffusion of impurities from the carbon to the solution. In an acidic environment (pH 2.5 in this work), the ozone molecule is relatively stable, yet active carbon causes its decomposition. This is the first report that indirectly indicates that contaminants on the surface of activated carbon (multivalent elements) contribute to the breakdown of ozone towards radicals, while the process of ozone decomposition by purified carbons does not follow the radical path in bulk solution. Carbon impurities also change the distribution of the reaction products formed by organic pollutants ozonation, which additionally confirms the radical process. The study showed that the use of unpurified activated carbon in the ozonation of succinic acid (SA) leads to the formation of a relatively large amount of oxalic acid (OA), which is a product of radical SA degradation. On the other hand, in solutions with purified carbon, the amount of OA generated is negligible.
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Affiliation(s)
- Lilla Fijołek
- Department of Analytical and Environmental Chemistry, Faculty of Chemistry, Adam Mickiewicz University Poznan, Uniwersytetu Poznańskiego 8, 61-614, Poznań, Poland
| | - Joanna Świetlik
- Department of Analytical and Environmental Chemistry, Faculty of Chemistry, Adam Mickiewicz University Poznan, Uniwersytetu Poznańskiego 8, 61-614, Poznań, Poland
| | - Marcin Frankowski
- Department of Analytical and Environmental Chemistry, Faculty of Chemistry, Adam Mickiewicz University Poznan, Uniwersytetu Poznańskiego 8, 61-614, Poznań, Poland.
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Fijołek L, Świetlik J, Frankowski M. The Role of Sulphate and Phosphate Ions in the Recovery of Benzoic Acid Self-Enhanced Ozonation in Water Containing Bromides. Molecules 2021; 26:molecules26092701. [PMID: 34062968 PMCID: PMC8125472 DOI: 10.3390/molecules26092701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 04/26/2021] [Accepted: 05/03/2021] [Indexed: 11/29/2022] Open
Abstract
The ozonation of aromatic compounds in low-pH water is ineffective. In an acidic environment, the decomposition of ozone into hydroxyl radicals is limited and insufficient for the degradation of organic pollutants. Radical processes are also strongly inhibited by halogen ions present in the reaction medium, especially at low pH. It was shown that even under such unfavorable conditions, some compounds can initiate radical chain reactions leading to the formation of hydroxyl radicals, thus accelerating the ozonation process, which is referred to as so-called “self-enhanced ozonation”. This paper presents the effect of bromides on “self-enhanced ozonation” of benzoic acid (BA) at pH 2.5. It is the first report to fully and quantitatively describe this process. The presence of only 15 µM bromides in water inhibits ozone decomposition and completely blocks BA degradation. However, the effectiveness of this process can be regained by ozonation in the presence of phosphates or sulphate. The addition of these inorganic salts to the bromide-containing solution helps to recover ozone decomposition and BA degradation efficiency. As part of this research, the fractions of hydroxyl, sulphate and phosphate radicals reacting with benzoic acid and bromides were calculated.
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Baghirzade BS, Yetis U, Dilek FB. Imidacloprid elimination by O 3 and O 3/UV: kinetics study, matrix effect, and mechanism insight. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:24535-24551. [PMID: 32451893 DOI: 10.1007/s11356-020-09355-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 05/18/2020] [Indexed: 06/11/2023]
Abstract
The removal of imidacloprid (IMI) from water by ozonation (O3) and photo-ozonation (O3/UV) was comparatively studied, paying particular attention to the kinetics, matrix effect, and mechanistic aspects of the processes. The IMI removal by O3 was considerably enhanced at alkaline pHs, leading to almost complete removal under 20 min with a pseudo-first-order rate constant of 0.2374 min-1 at pH 8.25. Three different matrices, Milli-Q water, full-scale vacuum rotating membrane bioreactor plant effluent (VRMBR WW), and laboratory-scale instantaneous fed-batch reactor bioreactor effluent (Bio WW) spiked with IMI, were tested. The ozonation, coupled with UV, improved IMI removal remarkably regardless of the wastewater matrix, and there occurred a six times decrease in ozonation time requirement for 99% IMI elimination at pH 7.25. The IMI degradation mechanism proved that IMI is an ozone-resistant pollutant and is mainly degraded by OH• via an indirect mechanism. The second-order rate constants for IMI degradation with OH• were calculated as 2.23 × 1011 and 9.08 × 1011 M-1 s-1 for the O3 alone and O3/UV processes, respectively. The IMI degradation pathway analysis showed that IMI lost NO2, HNO2, and then Cl- from its structure, and the O3/UV process yielded fewer by-products than O3.
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Affiliation(s)
- Busra Sonmez Baghirzade
- Department of Environmental Engineering, Middle East Technical University, Dumlupinar Bulvari, 06800, Ankara, Turkey
| | - Ulku Yetis
- Department of Environmental Engineering, Middle East Technical University, Dumlupinar Bulvari, 06800, Ankara, Turkey
| | - Filiz B Dilek
- Department of Environmental Engineering, Middle East Technical University, Dumlupinar Bulvari, 06800, Ankara, Turkey.
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Ruffino B, Zanetti M. Orthophosphate vs. bicarbonate used as a buffering substance for optimizing the bromide-enhanced ozonation process for ammonia nitrogen removal. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 692:1191-1200. [PMID: 31539950 DOI: 10.1016/j.scitotenv.2019.07.251] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 07/16/2019] [Accepted: 07/16/2019] [Indexed: 06/10/2023]
Abstract
Bromide-enhanced ozonation (BEO) process can be a fast and effective solution for the complete removal of total nitrogen (TN) from wastewaters containing from moderate to high concentrations of ammonia nitrogen (AN). Like the traditional biological process of AN oxidation, even BEO requires the presence of buffering agents, in order to oppose the progressive acidification induced by the reaction. This study compares the effect of two buffering substances (namely bicarbonate and mixtures of orthophosphates) in hindering the acidification caused by AN oxidation and, consequently, optimizing the overall efficiency of the process. Tests were carried out with on-purpose made solutions containing concentrations of AN of 5-10 mM. The range of [Br-]/[O3] ratio values was from 12 to 18, so as to make ozone the limiting factor in HOBr generation. The results of this study proved that, in the absence of natural buffering agents, mixtures of orthophosphates must be preferred to the more traditionally employed bicarbonate to control the pH evolution of BEO process. In fact, orthophosphates proved to be capable to guarantee an initial pH of the wastewater in the order of 7.5, thus making the zero-order AN removal rates 15% faster than those observed in the presence of bicarbonate. Furthermore, in the presence of mixtures of orthophosphates, the generation of ozonation byproducts in the oxidized form (nitrate, bromate) was reduced by over 70%. Finally, the fine control of pH obtained with orthophosphates in the BEO of AN makes that process an attractive solution for the treatment of effluents containing AN, thus preventing the discharge of residual nitrogen into aquatic environments and avoiding eutrophication of receiving water bodies.
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Affiliation(s)
- Barbara Ruffino
- Department of Environment, Land and Infrastructure Engineering, Politecnico di Torino, corso Duca degli Abruzzi, 24, 10129 Torino, Italy; CleanWaterCenter@PoliTo, Politecnico di Torino, corso Duca degli Abruzzi 24, 10129 Torino, Italy.
| | - Mariachiara Zanetti
- Department of Environment, Land and Infrastructure Engineering, Politecnico di Torino, corso Duca degli Abruzzi, 24, 10129 Torino, Italy
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