Water SA最新文献

{"title":"Impact of Stepwise Salinity Elevation on Nitrogen Removal and Microbial Properties of Morphologically Distinct Anammox Sludge","authors":"Keying Sun, Huining Zhang, Kefeng Zhang, Jianqing Ma, Zhigang Pan, Shuting Zhang","doi":"10.3390/w17172611","DOIUrl":"https://doi.org/10.3390/w17172611","url":null,"abstract":"The anaerobic ammonium oxidation (anammox) process offers potential for saline wastewater treatment but is hindered by salt inhibition. This study investigates the salt tolerance mechanisms of granular (R1), biofilm-carrier (R2), and floccular (R3) sludge in up-flow anaerobic sludge blanket (UASB) reactors under 0–20 g/L NaCl. Granular sludge outperformed other biomass types, maintaining >90% ammonia nitrogen (NH4+-N) removal at 20 g/L NaCl due to structural stability and extracellular polymeric substances (EPS) adaptation (shift from hydrophobic proteins to polysaccharides). Microbial analysis revealed a transition from Planctomycetes/Proteobacteria to salt-tolerant Pseudomonadota, with Candidatus_Kuenenia replacing Candidatus_Brocadia as the dominant anaerobic ammonium oxidation bacteria (AnAOB) (reaching 14.5% abundance in R1). Genetic profiling demonstrated coordinated nitrogen metabolism: Hzs/Hdh inhibition (>85%) and NirBD/NrfAH activation (0.23%) elevated NH4+-N, while NarGIV/NapA decline (1.10%→0.58%) increased nitrate nitrogen (NO3−-N). NxrB/NirSK maintained low nitrite nitrogen (NO2−-N), and GltBD upregulation (0.43%) enhanced osmoregulation. These findings underscore the superior resilience of granular sludge under high salinity, linked to microbial community shifts and metabolic adaptations. This study provides critical insights for optimizing anammox processes in saline environments, emphasizing the importance of biomass morphology and microbial ecology in mitigating salt inhibition.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"17 17","pages":"2611-2611"},"PeriodicalIF":0.0,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.mdpi.com/2073-4441/17/17/2611/pdf?version=1756909462","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147331593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Peroxymonosulfate Activation by Sludge-Derived Biochar via One-Step Pyrolysis: Pollutant Degradation Performance and Mechanism","authors":"Yi Wang, Lianqing Li, Hao Zhou, Jingjing Zhan","doi":"10.3390/w17172588","DOIUrl":"https://doi.org/10.3390/w17172588","url":null,"abstract":"Municipal wastewater treatment relies primarily on biological methods, yet effective disposal of residual sludge remains a major challenge. Converting sludge into biochar via oxygen-limited pyrolysis presents a novel approach for waste resource recovery. This study prepared sludge-based biochar (SBC) through one-step pyrolysis of sewage sludge and applied it to activate peroxymonosulfate (PMS) for degrading diverse contaminants. Characterization (SEM, XPS, FTIR) revealed abundant pore structures and diverse surface functional groups on SBC. Using Acid Orange 7 (AO7) as the target pollutant, SBC effectively degraded AO7 across pH 3.0–9.0 and catalyst dosages (0.2–2.0 g·L−1), achieving a maximum observed rate constant (kobs) of 0.3108 min–1. Salinity and common anions showed negligible inhibition on AO7 degradation. SBC maintained 95% degradation efficiency after four reuse cycles and effectively degraded sulfamethoxazole, sulfamethazine, and rhodamine B besides AO7. Mechanistic studies (chemical quenching and ESR) identified singlet oxygen (1O2) and superoxide radicals (O2•− ) as the dominant reactive oxygen species for AO7 degradation. XPS indicated a 39% reduction in surface carbonyl group content after cycling, contributing to activity decline. LC-MS identified five intermediates, suggesting a potential degradation pathway driven by SBC/PMS system. ECOSAR model predictions indicated significantly reduced biotoxicity of the degradation products compared to AO7. This work provides a strategy for preparing sludge-derived catalysts for PMS activation and pollutant degradation, enabling effective solid waste resource utilization.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"17 17","pages":"2588-2588"},"PeriodicalIF":0.0,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.mdpi.com/2073-4441/17/17/2588/pdf?version=1756738640","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147333505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Formation of AOX and Cl/Br/I-THMs During NaClO Disinfection: A Comprehensive Study","authors":"Chao Feng, Tongyu Liu, Yongping Shi, Jimin Shen, Lei Yuan, Yuanqing Guo","doi":"10.3390/w17172563","DOIUrl":"https://doi.org/10.3390/w17172563","url":null,"abstract":"The interaction of disinfectants with bromide/iodide ions and natural organic matter (NOM) generates brominated/iodinated disinfection byproducts (Br/I-DBPs), known for their heightened cytotoxicity and genotoxicity relative to chlorinated DBPs. This study investigated Br/I-DBP formation during sodium hypochlorite (NaClO) disinfection of lignin-containing synthetic water by quantifying adsorbable organic halogens (AOX) and trihalomethanes (THMs). Disinfection of bromide-containing water yielded a bromide ion (Br−) to adsorbable organic bromine (AOBr) conversion rate of approximately 60%, with bromine within THMs accounting for about 30% of the total AOBr, indicating significant brominated DBP formation where THMs represent a major fraction. Conversely, iodide ion (I−) conversion to adsorbable organic iodine (AOI) is minimal, suggesting negligible iodinated DBP formation under NaClO disinfection. Examination of key parameters revealed that brominated THM (Br-THM) formation decreased with increasing lignin concentration, while iodinated THM (I-THM) formation increased. The effect of chlorine dose differed: Br-THM formation exhibited an initial increase followed by a decrease at higher doses, whereas I-THM formation consistently decreased. Both Br-THM and I-THM formation increased with higher bromide or iodide ion concentration and with increasing pH. These results highlight the distinct pathways and influencing factors governing brominated versus iodinated DBP formation in lignin-containing waters disinfected with hypochlorite.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"17 17","pages":"2563-2563"},"PeriodicalIF":0.0,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.mdpi.com/2073-4441/17/17/2563/pdf?version=1756538467","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147914996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preliminary Study on the Inhibitory Effect and Mechanism of Oleic Acid in Cylindrospermopsis raciborskii","authors":"Xiaojia Huang, Yuanyuan Hu, Xiaowei Cheng, Weibin Pan","doi":"10.3390/w17172561","DOIUrl":"https://doi.org/10.3390/w17172561","url":null,"abstract":"Cylindrospermopsis raciborskii is a toxin-producing cyanobacterium that is easy to overlook. It has strong environmental adaptability and is currently spreading around the world and gradually dominating to form a persistent bloom, causing ecological and environmental risks and drinking water safety issues. In this study, we systematically investigated the inhibitory effects of oleic acid on C. raciborskii and elucidated the underlying mechanisms through morphological observation, physiological assays, and bioinformatics analysis. Our results demonstrated that oleic acid strongly inhibits the growth of C. raciborskii, with a 72 h half-maximal effective concentration (EC50) of 0.903 mg·L−1. At 1.6 mg·L−1, oleic acid achieved an inhibition rate of 99.5% within 48 h, indicating rapid suppression of cyanobacterial growth. Physiological analyses revealed that oleic acid severely impaired photosynthetic activity, as evidenced by significant reductions in key parameters (rETRmax, α, Fv/Fm, and Fv/Fo) and altered photosynthetic pigment composition, suggesting structural and functional damage to the photosynthetic apparatus. Morphological observations further showed that oleic acid disrupted filament integrity, inducing cell shrinkage, cytoplasmic vacuolation, cell wall detachment, membrane rupture, and eventual cellular disintegration. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis indicated that oleic acid interferes with multiple metabolic processes, including nutrient and cofactor synthesis, membrane transport, and signal transduction, ultimately triggering algal cell death. This study highlights oleic acid as a promising eco-friendly agent for mitigating C. raciborskii blooms, offering potential applications in ecological prevention and emergency bloom control.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"17 17","pages":"2561-2561"},"PeriodicalIF":0.0,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.mdpi.com/2073-4441/17/17/2561/pdf?version=1756482706","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147905802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Carbon Reduction Strategies for Typical Wastewater Treatment Processes (A2/O): Response Surface Optimization, Mechanism, and Application Analysis","authors":"Siqi Tong, Guangbing Liu, Xi Meng, Chun‐Kai Huang, Siwen Chen, Zhiquan Xiang, Weijing Liu, Jinyou Shen, Yi Wang","doi":"10.3390/w17172505","DOIUrl":"https://doi.org/10.3390/w17172505","url":null,"abstract":"With increasing wastewater treatment demands and decarbonization goals, synergistic reduction in pollutants and green house gas (GHG) emissions is crucial. High process emissions like N2O pose significant challenges, yet optimized carbon reduction strategies for conventional plants are lacking. This study developed three mathematical models to quantify the impact of dissolved oxygen (DO), influent salinity, and C/N ratio on direct emissions (CH4, N2O) and indirect emissions. Response Surface Methodology (RSM) optimized these factors to minimize GHG emissions under three accounting scenarios: (1) plants with CH4 reuse systems: salinity = 0.5 g L−1, DO = 3.67 mg L−1, C/N = 12.75; (2) plants focusing solely on direct emissions: salinity = 0.5 g L−1, DO = 3.35 mg L−1, C/N = 3; and (3) plants assessing total emissions: salinity = 0.5 g L−1, DO = 2.5 mg L−1, C/N = 7.18. Key findings indicated that increasing salinity exacerbated greenhouse gas emissions. Elevated DO levels in the aerobic stage reduced N2O emissions but increased indirect emissions in the A2/O process. Higher C/N ratios promoted anaerobic CH4 production, but sufficient carbon reduced N2O by enabling complete heterotrophic denitrification. A 60−day continuous GHG emissions monitoring campaign was conducted at a WWTP to validate the actual emission reductions achievable under the identified optimal control conditions. An analysis and comparison of operational and economic costs were also performed. The findings provide practical insights into sustainable GHG emission management and offer potential solutions to advance the synergistic reduction in GHG emissions and pollutants.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"17 17","pages":"2505-2505"},"PeriodicalIF":0.0,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.mdpi.com/2073-4441/17/17/2505/pdf?version=1755866939","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147885720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrogeochemistry of Surface Waters in the Iron Quadrangle, Brazil: High-Resolution Mapping of Potentially Toxic Elements in the Velhas and Paraopeba River Basins","authors":"Raphael de Vicq Ferreira da Costa, Mariângela Garcia Praça Leite, Lucas Pereira Leão, Hermínio Arias Nalini Júnior, Darllan Collins da Cunha e Silva, Rita Fonseca, Teresa Maria Fernandes Valente","doi":"10.3390/w17162446","DOIUrl":"https://doi.org/10.3390/w17162446","url":null,"abstract":"This study delivers a pioneering, high-resolution hydrogeochemical assessment of surface waters in the Upper Velhas and Upper Paraopeba river basins within Brazil’s Iron Quadrangle—an area of critical socioeconomic importance marked by intensive mining and urbanization. Through a dense sampling network of 315 surface water points (one every 23 km2), the research generates an unprecedented spatial dataset, enabling the identification of contamination hotspots and the differentiation between lithogenic and anthropogenic sources of potentially toxic elements (PTEs). Statistical methods, including exploratory data analysis and cluster analysis, were applied to determine background and anomalous concentrations of potentially toxic elements (PTEs). Geospatial distribution maps were generated using GIS. The results revealed widespread contamination by As, Cd, Cr, Ni, Pb, and Zn, with many samples exceeding Brazilian, European, and global drinking water standards. Arsenic and cadmium anomalies in rural and peri-urban communities raise concerns due to the direct consumption of contaminated water. The innovative application of dense spatial sampling and integrated geostatistical methods offers new insights into the pathways and sources of PTE pollution, identifying specific lithological units (e.g., gold schists, mafic intrusions) and land uses (e.g., urban effluents, mining sites) associated with elevated contaminant levels. By establishing robust regional geochemical baselines and source attributions, this study sets a new standard for environmental monitoring in mining-impacted watersheds and provides a replicable framework for water governance, environmental licensing, and risk management in similar regions worldwide.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"17 16","pages":"2446-2446"},"PeriodicalIF":0.0,"publicationDate":"2025-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.mdpi.com/2073-4441/17/16/2446/pdf?version=1755585569","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147901940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sodium p-Perfluorous Nonenoxybenzene Sulfonate (OBS) Induces Developmental Toxicity Through Apoptosis in Developing Zebrafish Embryos: A Comparison with Perfluorooctane Sulfonate","authors":"Yilong Zou, Xueping Huang, Xianglian Wang, Manqing Xu, Yonghua Sun","doi":"10.3390/w17162450","DOIUrl":"https://doi.org/10.3390/w17162450","url":null,"abstract":"Perfluorooctane sulfonate (PFOS) is a representative persistent organic pollutant that exerts toxic effects on aquatic organisms. As an alternative to PFOS, sodium p-perfluorous nonenoxybenzene sulfonate (OBS) has been frequently detected in aquatic environments and human tissues in recent years. However, its toxic effects on aquatic organisms and potential health risks to humans remain unclear. Zebrafish embryos are transparent and amenable to in vivo manipulation and observation. Therefore, in the present study, we investigated its developmental toxicity in zebrafish embryos, with PFOS as the positive control. We exposed zebrafish embryos to different concentrations of OBS (15, 20, and 25 mg/L) and PFOS (15 mg/L) for 2–168 h post fertilization (hpf) and then examined physiological and gene expression changes. At 24 hpf, spontaneous twitches in the 25 mg/L OBS group decreased to (5 ± 0.34)/min. By 48 hpf, the 20 mg/L OBS group’s hatching rate was (47.78 ± 2.22)%, significantly lower than the control. At 72 hpf, heart rates in both the PFOS and OBS groups were elevated, at 82 ± 0.6, 84.5 ± 0.5, 89.4 ± 0.3, and 93.7 ± 0.4, respectively. Similarly to PFOS, OBS induced developmental toxicity in zebrafish embryos. In addition, both OBS and PFOS exposure downregulated the expression level of anti-apoptotic Bcl-2 in zebrafish embryos, with a notable 0.53-fold decrease observed in the 25 mg/L OBS group. Conversely, they upregulated the expression levels of pro-apoptotic Bax, Caspase-3, and Caspase-9, with Caspase-3 expression increasing 1.14-, 1.5-, and 1.7-fold in the 15 mg/L PFOS, 20 mg/L OBS, and 25 mg/L OBS groups, respectively. These OBS- and PFOS-induced changes in gene expression increased apoptosis, suggesting that OBS can induce developmental toxicity in zebrafish embryos, and that its effect is comparable to that of PFOS. Therefore, considering its aquatic toxicity, measures aimed at limiting or remediating OBS pollution in the environment are necessary.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"17 16","pages":"2450-2450"},"PeriodicalIF":0.0,"publicationDate":"2025-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.mdpi.com/2073-4441/17/16/2450/pdf?version=1755595791","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147905736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated Assessment of Groundwater Quality Using Water Quality Indices, Geospatial Analysis, and Neural Networks in a Rural Hungarian Settlement","authors":"Dániel Balla, Levente Tari, András Hajdú, Emőke Kiss, Marianna Zichar, Tamás Mester","doi":"10.3390/w17162371","DOIUrl":"https://doi.org/10.3390/w17162371","url":null,"abstract":"In the present study, the changes in the groundwater quality in a Hungarian settlement, Báránd, were examined, nine years after the construction of a sewerage network. The sewerage network in the study area was completed in 2014, with a household connection rate exceeding 97% in 2023. In the summer of 2023, water samples were taken from 37 dug groundwater wells. Changes in the water quality were assessed using three water quality indicators (the Water Quality Index (WQI), Contamination degree (Cd), and Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI)) and geographic information (GIS), data visualization systems, and artificial intelligence (AI). During the evaluation of the quality of the groundwater, eight water chemical parameters were used (pH, EC, NH4+, NO2−, NO3−, PO43−, COD, Na+). Based on interpolated maps and water quality indices, it was established that while an increasing portion of the area exhibits adequate or good water quality compared to the pre-sewerage period, a deterioration has occurred relative to recent years. Even nine years after the sewerage network construction, elevated concentrations of inorganic nitrogen forms and organic matter persist, indicating the continued presence of accumulated pollutants, as confirmed by all three water quality indicators to varying degrees and spatial patterns. The interactive data visualization and cloud-based sharing of the data of the water quality geodatabase were made freely available with the help of Tableau Public. A Feed-Forward Neural Network (FFNN) was developed to predict the groundwater quality, estimating the water quality statuses of three water quality indicators based on water chemistry parameters. The results showed that the applied training algorithms and activation functions proved to be the most effective in the case of different network structures. The most accurate prediction of the WQI and CCME WQI indicators was provided by the Bayesian control algorithm (trainbr), which achieved the lowest mean-squared error (RMSEWQI = 0.1205, RMSECCME WQI = 0.1305) and the highest determination coefficient (R2WQI = 0.9916, R2CCME WQI = 0.9838). For the Cd index, the accuracy of the model was lower (RMSE = 0.1621, R2 = 0.9714), suggesting that this indicator is more difficult to predict. With regard to our study, it should be emphasized that data visualization is a particularly practical tool for the post-processing of spatial monitoring data, as it is suitable for displaying information in an intuitive, visual form, for discovering spatial patterns and relationships, and for performing real-time analyses. AI is expected to further increase visualization efficiency in the future, enabling the rapid processing of large amounts of data and spatial databases, as well as the identification of complex patterns.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"17 16","pages":"2371-2371"},"PeriodicalIF":0.0,"publicationDate":"2025-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147917900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Activation of Peracetic Acid by Ozone for Recalcitrant Pollutant Degradation: Accelerated Kinetics, Byproduct Mitigation, and Microbial Inactivation","authors":"Dihao Bai, Liu Cong, Siqing Zhang, Huiyu Dong, Lei Sun, Xiangjuan Yuan","doi":"10.3390/w17152240","DOIUrl":"https://doi.org/10.3390/w17152240","url":null,"abstract":"Iopamidol (IPM), as a typical recalcitrant emerging pollutant and precursor of iodinated disinfection by-products (I-DBPs), is unsuccessfully removed by conventional wastewater treatment processes. This study comprehensively evaluated the ozone/peracetic acid (O3/PAA) process for IPM degradation, focusing on degradation kinetics, environmental impacts, transformation products, ecotoxicity, disinfection byproducts (DBPs), and microbial inactivation. The O3/PAA system synergistically activates PAA via O3 to generate hydroxyl radicals (•OH) and organic radicals (CH3COO• and CH3CO(O)O•), achieving an IPM degradation rate constant of 0.10 min−1, which was significantly higher than individual O3 or PAA treatments. The degradation efficiency of IPM in the O3/PAA system exhibited a positive correlation with solution pH, achieving a maximum degradation rate constant of 0.23 min−1 under alkaline conditions (pH 9.0). Furthermore, the process demonstrated strong resistance to interference from coexisting anions, maintaining robust IPM removal efficiency in the presence of common aqueous matrix constituents. Furthermore, quenching experiments revealed •OH dominated IPM degradation in O3/PAA system, while the direct oxidation by O3 and R-O• played secondary roles. Additionally, based on transformation products (TPs) identification and ECOSAR predictions, the primary degradation pathways were elucidated and the potential ecotoxicity of TPs was systematically assessed. DBPs analysis after chlorination revealed that the O3/PAA (2.5:3) system achieved the lowest total DBPs concentration (99.88 μg/L), representing a 71.5% reduction compared to PAA alone. Amongst, dichloroacetamide (DCAM) dominated the DBPs profile, comprising > 60% of total species. Furthermore, the O3/PAA process achieved rapid 5–6 log reductions of E. coli. and S. aureus within 3 min. These results highlight the dual advantages of O3/PAA in effective disinfection and byproduct control, supporting its application in sustainable wastewater treatment.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"17 15","pages":"2240-2240"},"PeriodicalIF":0.0,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.mdpi.com/2073-4441/17/15/2240/pdf?version=1753688625","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147921905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cu–Co–O-Codoped Graphite Carbon Nitride as an Efficient Peroxymonosulfate Activator for Sulfamethoxazole Degradation: Characterization, Performance, and Mechanism","authors":"Qiliang Xiao, Jun Nan","doi":"10.3390/w17142161","DOIUrl":"https://doi.org/10.3390/w17142161","url":null,"abstract":"This study presents the development of a novel Cu–Co–O-codoped graphitic carbon nitride (g-C3N4) catalyst for efficient peroxymonosulfate (PMS) activation to degrade sulfamethoxazole (SMX) in aqueous environments. The synthesized Cu–Co–O-g-C3N4 catalyst demonstrated exceptional catalytic performance, achieving 90% SMX removal within 10 min—significantly outperforming pristine g-C3N4 (14%) and O-doped g-C3N4 (22%)—with a reaction rate constant of 0.63 min−1. The superior activity was attributed to the synergistic effects of Cu-Co bimetallic doping and oxygen incorporation, which enhanced the active sites, stabilized metal ions, and minimized leaching. Mechanistic studies revealed a dual-pathway degradation process: (1) a radical pathway dominated by sulfate radicals (SO4•−) and (2) a non-radical pathway driven by singlet oxygen (1O2), with the latter identified as the dominant species through quenching experiments. The catalyst exhibited broad pH adaptability and optimal performance at neutral to alkaline conditions. Characterization techniques (XRD, FTIR, XPS) confirmed successful doping and revealed that oxygen incorporation modified the electronic structure of g-C3N4, improving charge carrier separation. This work provides a sustainable strategy for antibiotic removal, addressing key challenges in advanced oxidation processes (AOPs), and highlights the potential of multi-heteroatom-doped carbon nitride catalysts for water purification.","PeriodicalId":23623,"journal":{"name":"Water SA","volume":"17 14","pages":"2161-2161"},"PeriodicalIF":0.0,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.mdpi.com/2073-4441/17/14/2161/pdf?version=1753079537","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147910675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}