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The presence of pharmaceutical pollutants in water bodies represents a significant environmental and public health concern, largely due to their inherent persistence and potential to induce antibiotic resistance. Advanced oxidation processes (AOPs) that employ peroxymonosulfate (PMS) activation have emerged as an effective means of degrading these contaminants. Bismuth oxyiodides (BiOI), which are known for their visible-light photocatalytic properties, demonstrate considerable potential for removal of pharmaceutical pollutants. This study examines the synthesis and performance of BiOI-based composites with barium ferrite (BFO) nanoparticles for enhanced PMS activation under visible light. BiOI and Bi 5 O 7 I were synthesized via solvothermal and electrodeposition methods, respectively, and their morphologies and crystalline structures were observed to exhibit distinctive characteristics following annealing. The formation of the composite with BFO resulted in an improvement in the catalytic properties, which in turn enhanced the surface area and availability of active sites. The objective of the photocatalytic studies was to evaluate the degradation and mineralization of tetracycline (TC) under visible light, PMS, and combined conditions. The Bi 5 O 7 I(ED)-BFO catalyst was identified as the optimal candidate, achieving up to 99.8% TC degradation and 99.4% mineralization within 90 min at room temperature. The synergistic effect of BFO in BiOI-based composites significantly enhanced performance across all conditions, indicating their potential for efficient remediation of pharmaceutical pollutant. The material's performance was further evaluated in tap water, where the degradation efficiency decreased to 56.4% and mineralization to 38.2%. These results reflect the challenges posed by complex water matrices. However, doubling the PMS concentration to 5 mM led to improved outcomes, with 93.8% degradation and 81.4% mineralization achieved. These findings demonstrate the material's robust potential for treating pharmaceutical pollutants in real-world conditions, advancing sustainable water treatment technologies. [Display omitted] • Solvothermal BiOI yield microspheres, while electrodeposition flower-like structures. • BaFe 12 O 19 nanoparticles in BiOI and Bi 5 O 7 I enhanced photocatalytic performance. • Bi 5 O 7 I (ED)-BFO composite showed highest degradation and mineralization efficiency. • Composites are stable and reusable 15 cycles for water pollutant degradation. [ABSTRACT FROM AUTHOR]

Isoquinoline (IQL), as a typical nitrogen-containing heterocyclic contaminant in coking wastewater, poses a serious threat to the aquatic environment and human health. Due to its chemical stability, traditional sewage treatment technology is not highly efficient in IQL removal. Advanced oxidation processes (AOPs) driven by ultraviolet radiation could be an effective treatment method, but it could generate toxic byproducts. In this work, the removal of IQL initiated by HO•, ClO•, Cl•, and SO 4 •- in UV/chlorine and UV/persulfate (PDS) process was comprehensively investigated, clarifying the degradation mechanism, reaction kinetics, and ecological toxicity. The findings indicate that the dominant oxidation mechanism of IQL by HO•, ClO•, and Cl• is radical adduct formation (RAF), while single electron transfer (SET) is the main reaction pathway of SO 4 •- with IQL. At 298 K and 1 atm, the order of rate constants for the reactions of IQL with active radicals is Cl• (6.23 × 1010 M−1 s−1) > SO 4 •- (8.81 × 109 M−1 s−1) > HO• (1.66 × 109 M−1 s−1) > ClO• (1.62 × 108 M−1 s−1). The acute and chronic toxicity of IQL and its degradation byproducts at three different trophic levels were evaluated using ECOSAR program. The byproducts produced by the oxidative degradation of IQL by HO• and SO 4 •- are mostly "not harmful", and their toxicity shows a decreasing trend compared to that of IQL. The byproducts derived from the reaction of IQL with Cl• are all "toxic" or "harmful", and the ranking of harm to three types of aquatic organisms is green algae > fish > daphnia. Hence, UV/PDS process could be more secure in pollutant disposal in wastewater. In actual water treatment process, merit attention should be paid to the potential hazards of the byproducts generated by various contaminants. [Display omitted] • The degradation mechanism of IQL in UV/Cl and UV/PDS processes was investigated. • The reaction kinetics and byproducts were clarified for degradation of IQL by active radicals. • The aquatic toxicity of IQL and by-products was evaluated. [ABSTRACT FROM AUTHOR]

Aniline, a common pollutant in industrial wastewater, requires an effective treatment method with minimal chemical usage. In this study, a two-stage catalytic oligomerization process has been developed to address this issue by converting soluble aniline into insoluble oligomers for wastewater treatment. In the first stage, aniline is oxidized using hydrogen peroxide (H 2 O 2) and a green catalyst, iron tetraamido macrocyclic ligand (Fe-TAML) to form aniline tetramers or pentamers. In the second stage, these oligoanilines undergo further oxidation with H 2 O 2 alone at a higher temperature, resulting in the formation of N-phenylphenazine or its derivatives. These macrocyclic compounds precipitate from the wastewater due to π− π stacking, allowing easy separation through decantation or gravity filtration. After process optimization, only 3 mg/L of Fe-TAML and 2 g/L of H 2 O 2 are required to treat 1 g/L of aniline, achieving a remarkable 96.8% aniline removal efficiency and a 62.5% precipitate yield. This two-stage oxidation approach shows promise for treating aniline and similar aromatic compounds in real industrial wastewater. [Display omitted] • Green catalyst Fe-TAML enables efficient sustainable aniline oligomerization. • Two-stage process transforms soluble aniline into precipitates in real wastewaters. • Low chemical usage, high atom economy with no secondary waste production. • Impressive efficiency achieves 96.8% aniline removal and yields 62.5% precipitate. • The recovered precipitates exhibit competitive supercapacitive property. [ABSTRACT FROM AUTHOR]

The removal of nanoplastics (NP) from water using various treatment processes has gained significant attention recently. This study comprehensively characterizes the degradation of polystyrene nanoparticles (concentration: 200 ppm, diameter: 140 nm) through UVC irradiation. For the first time, we compared four analytical methods to monitor removal efficiency: Py-GCMS, UV–Visible spectroscopy, TOC, and Turbidity. Additionally, DLS, TEM, and SEC were used to understand changes in particle size, morphology, and molecular weight. Results showed that Py-GCMS overestimated the removal rate by a factor of 2 compared to Turbidity and UV–Visible measurements, which were in agreement. Furthermore, after 200 h of irradiation, the styrene signal disappears from the pyrogram, although the mineralization rate reaches only 50%, as determined by total organic carbon (TOC) analysis. The particle size decreased slowly, reaching 100 nm after 150 h, while a significant decrease in molecular weight indicated high chain-scission. These findings emphasize the importance of a multi-analytical approach to accurately assess NP removal efficiency and understand degradation mechanisms. [Display omitted] • UVC irradiation effectively removes polystyrene nanoparticles from water. • Removal efficiency measurement depends on the analytical technique employed. • Py-GCMS may overestimate efficiency when chain scission is prevalent. • UV and Turbidity measurements offer rapid performance assessments. • Reliable results require a multi-analytical approach and standardized protocols. [ABSTRACT FROM AUTHOR]

The contamination of water sources by pharmaceutical compounds presents global environmental and health risks, necessitating the development of efficient water treatment technologies. In this study, the synthesis, characterization, and evaluation of a novel graphitic carbon nitride-calcined (Fe–Ca) layered double hydroxide (gC 3 N 4 -CLDH) composite for electrochemical degradation of sulfamethoxazole (SMX) in water yielded significant outcomes are reported. SEM, XRD, FTIR, and XPS analyses confirmed well-defined composite structures with unique morphology and crystalline properties. Electrochemical degradation experiments demonstrated >98% SMX removal and >75% TOC removal under optimized conditions, highlighting its effectiveness. The composite exhibited excellent mineralization efficiency across various pH levels, with superoxide radicals (O 2 ●–) and hydroxyl radicals (●OH) identified as primary reactive oxygen species. With remarkable regeneration capability for up to 7 cycles, the gC 3 N 4 -CLDH composite emerges as a highly promising solution for sustainable water treatment. Humic acid (HA) in water significantly slows SMX degradation, suggests complicating SMX degradation with natural organic matter. Despite this, the gC 3 N 4 -CLDH composite effectively degrades SMX in groundwater and industrial wastewater, with slight efficiency reduction in the latter due to higher impurity levels. These findings highlight the complexities of treating pharmaceutical pollutants in various water types. Overall, gC 3 N 4 -CLDH's high removal efficiency, broad pH applicability, sustainability, and mechanistic insights provide a solid foundation for future research and real-world environmental applications. [Display omitted] • The gC 3 N 4 -CLDH composite exhibited superior SMX mineralization. • Carbon felt was used as electrode base material providing a high surface area. • Achieved >98% removal of sulfamethoxazole (SMX) and substantial TOC reduction. • Maintained high mineralization efficiency across diverse pH environments. • Catalyst exhibited excellent regeneration, sustaining efficiency over multiple cycles. [ABSTRACT FROM AUTHOR]

The present study demonstrates, for the first time, the feasibility of a two-step process consisting of Electro-Fenton (EF) followed by microalgae to treat highly loaded real food processing wastewater along with resource recovery. In the first step, EF with a carbon felt cathode and Ti/RuO 2 –IrO 2 anode was applied at different current densities (3.16 mA cm−2, 4.74 mA cm−2 and 6.32 mA cm−2) to decrease the amount of organic matter and turbidity and enhance biodegradability. In the second step, the EF effluents were submitted to microalgal treatment for 15 days using a mixed culture dominated by Scenedesmus sp., Chlorosarcinopsis sp., and Coelastrum sp. Results showed that current density impacted the amount of COD removed by EF, achieving the highest COD removal of 77.5% at 6.32 mA cm−2 with >95% and 74.3% of TSS and PO 4 3− removal, respectively. With respect to microalgae, the highest COD removal of 85% was obtained by the culture in the EF effluent treated at 6.32 mA cm−2. Remarkably, not only 85% of the remaining organic matter was removed by microalgae, but also the totality of inorganic N and P compounds, as well as 65% of the Fe catalyst that was left after EF. The removal of inorganic species also demonstrates the high complementarity of both processes, since EF does not have the capacity to remove such compounds, while microalgae do not grow in the raw wastewater. Furthermore, a maximum of 0.8 g L−1 of biomass was produced after cultivation, with an accumulation of 32.2% of carbohydrates and 25.9% of lipids. The implementation of the two processes represents a promising sustainable approach for the management of industrial effluents, incorporating EF in a water and nutrient recycling system to produce biomass that could be valorized into clean fuels. [Display omitted] • A novel two-step electro-Fenton (EF)-microalgae process was proposed. • EF reduced organic load and suspended solids from a raw real industrial effluent. • After EF, microalgae removed remaining N and P compounds as well as Fe catalyst. • Microalgae accumulated carbohydrates and lipids with potential for biofuel production. • EF-microalgae is a sustainable option for wastewater treatment with resources recovery. [ABSTRACT FROM AUTHOR]

Carbonate radical (CO 3 •−) has been proved to be an important secondary radical in advanced oxidation processes due to various radical reactions involved HCO 3 −/CO 3 2−. However, the roles and contributions of CO 3 •− in organic micropollutant degradation have not been explored systematically. Here, we quantified the impact of CO 3 •− on the degradation kinetics of propranolol, a representative pollutant in the UV/peroxymonosulfate (PMS) system, by constructing a steady-state radical model. Substantially, the measured values were coincident with the predictive values, and the contributions of CO 3 •− on propranolol degradation were the water matrix-dependent. Propranolol degradation increased by 130% in UV/PMS system containing 10 mM HCO 3 −, and the contribution of CO 3 •− was as high as 58%. Relatively high pH values are beneficial for propranolol degradation in pure water containing HCO 3 −, and the contributions of CO 3 •− also enhanced, while an inverse phenomenon was shown for the effects of propranolol concentrations. Dissolved organic matter exhibited significant scavenging effects on HO•, SO 4 •−, and CO 3 •−, substantially retarding the elimination process. The developed model successfully predicted oxidation degradation kinetics of propranolol in actual sewage, and CO 3 •− contribution was up to 93%, which in indicative of the important role of CO 3 •− in organic micropollutant removal via AOPs treatment. [Display omitted] • HCO 3 − in natural water bodies was studied and fully utilized. • HCO 3 − not only serves as a quencher for free radicals, but also as a source of CO 3.•−. • CO 3.•− plays an important role in pollutant degradation. • Steady-state free radical model successfully predicts pollutant degradation rates. • Steady-state free radical model successfully predicts contribution of free radicals. [ABSTRACT FROM AUTHOR]

Plastic products have gained global popularity due to their lightweight, excellent ductility, high durability, and portability. However, out of the 8.3 billion tons of plastic waste generated by human activities, 80% of plastic waste is discarded due to improper disposal, and then transformed into microplastic pollution under the combined influence of environmental factors and microorganisms. In this comprehensive study, we present a thorough review of recent advancements in research on the source, distribution, and effect of microplastics. More importantly, we conducted deep research on the catalytic degradation technologies of microplastics in water, including advanced oxidation and photocatalytic technologies, and elaborated on the mechanisms of microplastics degradation in water. Besides, various strategies for mitigating microplastic pollution in aquatic ecosystems are discussed, ranging from policy interventions, the initiative for plastic recycling, the development of efficient catalytic materials, and the integration of multiple technological approaches. This review serves as a valuable resource for addressing the challenge of removing microplastic contaminants from water bodies, offering insights into effective and sustainable solutions. Environmental problems caused by plastic pollution in water bodies are among the most pressing issues of our time. This review introduces and discusses the source, distribution, and ecological impact of microplastics. Finally, the study on degradation of microplastic by advanced oxidation processes are discussed. [Display omitted] • The source, distribution, and impact of MPs has been discussed. • Research on MPs removal based on AOPs has been summarized and discussed. • Multiple treatment processes should be combined to removal MPs in water. • Perspectives in the MPs pollution control in water were pointed out. [ABSTRACT FROM AUTHOR]

Research to increase biomethane recovery efficiency from thickened sewage sludge (TSWS) using sustainable anaerobic digestion (AD) in municipal wastewater treatment plants is ongoing. Pretreating substrates is known to increase organic biodegradation and biomethane conversion rates in AD. Cold plasma (CP), a recently adopted advanced oxidation processes (AOP) has emerged as an alternative to accelerate pretreatment times under different operation variables. This study assessed raw and CP-pretreated TSWS in an anaerobic sequencing batch reactor (ASBR) and anaerobic membrane bioreactor (AnMBR). The effects of incremental organic loading rates (OLR) and nitrogenous compounds concentration on enhanced CH 4 bioconversion efficiency were evaluated. We found that the AnMBR outperformed the ASBR, with an overall chemical oxygen demand (COD) conversion rate of 67%, lower total nitrogen (T–N) accumulation (594 mg L−1), and an overall methane yield of 0.24 L CH 4 g−1 COD. CP pretreatment improved TSWS AD, resulting in more efficient COD removal and methane recovery. This study suggests that CP technology is a promising pretreatment to improve AD when treating TSWS. [Display omitted] • Cold plasma enhances the anaerobic membrane bioreactor performance. • Reactive chemical species reduce nitrogenous compounds in thickened sewage sludge. • Reducing total and free NH 3 nitrogen improves methanogenesis under incremental OLR. • Cold plasma pretreatment mitigates membrane fouling and alkali metals accumulation. [ABSTRACT FROM AUTHOR]

Pharmaceutical active compound (PhAC) residues are considered an emerging micropollutant that enters the aquatic environment and causes harmful ecotoxicity. The significant sources of PhACs in the environment include the pharmaceutical industry, hospital streams, and agricultural wastes (animal husbandry). Recent investigations demonstrated that wastewater treatment plants (WWTPs) are an important source of PhACs discharging ecosystems. Several commonly reported that PhACs are detected in a range level from ng L−1 to μg L−1 concentration in WWTP effluents. These compounds can have acute and chronic adverse impacts on natural wildlife, including flora and fauna. The approaches for PhAC removals in WWTPs include bioremediation, adsorption (e.g., biochar, chitosan, and graphene), and advanced oxidation processes (AOPs). Overall, adsorption and AOPs can effectively remove PhACs from wastewater aided by oxidizing radicals. Heterogeneous photocatalysis has also proved to be a sustainable solution. Bioremediation approaches such as membrane bioreactors (MBRs), constructed wetlands (CWs), and microalgal-based systems were applied to minimize pharmaceutical pollution. Noteworthy, applying MBRs has illustrated high removal efficiencies of up to 99%, promising prospective future. However, WWTPs should be combined with advanced solutions, e.g., AOPs/photodegradation, microalgae–bacteria consortia, etc., to treat and minimize their accumulation. More effective and novel technologies (e.g., new generation bioremediation) for PhAC degradation must be investigated and specially designed for a low-cost and full-scale. Investigating green and eco-friendly PhACs with advantages, e.g., low persistence, no bioaccumulation, less or non-toxicity, and environmentally friendly, is also necessary. [Display omitted] • PhACs are found in the range from ng to μg L−1 concentration in WWTPs effluents • Pharmaceuticals have both acute and chronic harmful impacts • AOPs reach high effective removal of pharmaceuticals from wastewater owing to oxidizing radicals • The high removal efficiency of up to 99% and MBRs indicate prospective treatment • Microalgal-based technologies were applied to minimize pharmaceuticals effectively [ABSTRACT FROM AUTHOR]

Organic pollutants in water are a serious problem because of their widespread presence, harming the ecosystem and human health. Of the commonly used advanced oxidation processes, a hybrid of ultrasound and the Fenton/Fenton-like technology has received increasing attention in treatment of aqueous organic pollutants. This hybrid is effective in degradation of organic pollutants, but its application has not been summarised. Herein, first, the application and influencing factors of this hybrid technology for organic pollutants degradation are introduced. Second, the mechanism of its action is discussed. Third, the current challenges and future perspectives associated with this technology are proposed. This review provides valuable information regarding this technology, deepens the understanding of its mechanisms of organic pollutants degradation and provides a reference for its use in treatment of aquatic environments. [Display omitted] • Combined ultrasound and Fenton/Fenton-like is a highly effective treatment. • Application, influential parameters, and reaction mechanism are described. • The advantages of ultrasound-Fenton/Fenton-like is introduced. • The future research perspectives and challenges are presented. [ABSTRACT FROM AUTHOR]

The management of wastewater produced from alkali/surfactant/polymer (ASP) flooding, known for its considerable volume and high emulsion stability, poses a challenge in oilfields globally. This study has demonstrated that ionizing irradiation is a promising pretreatment method for ASP wastewater to improve oil-water separation. After a settling time of 1 h, approximately 69.5% of oil remained in the raw ASP wastewater, while only 20–29% of the oil persisted in the liquid phase following radiation at absorbed doses ranging from 0.1 to 5.0 kGy. A noticeable increase in the size of oil droplets and reduction in turbidity was observed after irradiation. Further analysis revealed that the combination of surfactant, sodium dodecyl sulfate (SDS) and alkali exhibits a synergistic impact, leading to a substantial reduction in interface tension of ASP wastewater. Notably, ionizing irradiation induces several key changes that are crucial for efficient demulsification. The transformation of the wastewater's rheological behavior from pseudoplastics to a Newtonian fluid accompanied by a reduction in viscosity, the increased interfacial tension at both liquid-air and liquid-oil interfaces, along with the degradation of organic components such as partly hydrolyzed polyacrylamide (HPAM) and SDS, all contribute to the coalescence and floatation of oil droplets. [Display omitted] • Electron beam is effective in enhancing oil-water separation of ASP wastewater. • With settling 1h oil remained 69.5% and 20–29% before and after 0.1–5.0 kGy radiation. • Rheological behavior changed from pseudoplastic to Newtonian after radiation. • IFT at liquid-air and liquid-oil interfaces increased and organics were degraded. • Coexistence of SDS and alkali play a vital role in IFT reduction of ASP wastewater. [ABSTRACT FROM AUTHOR]

In drinking water treatment, complete mineralization of organophosphorus pesticides (OPPs) by UV-based advanced oxidation processes (UV AOPs) is rarely achieved. The formation of intermediate oxidation byproducts would likely have some profound effects on toxicity of the reaction solutions. This study investigated the intermediate oxidation byproducts, transformation pathway and toxicity of malathion solutions during the treatment processes of UV alone, UV/H 2 O 2 , UV/TiO 2 and UV/Fenton. The main intermediate oxidation byproducts were derived using ultra-performance liquid chromatography - electrospray - time-of-flight mass spectrometry. Thereby the transformation pathway for each of these treatment processes was proposed. The results indicate that in UV photolysis, the transformation pathway of malathion proceeded initially via cleavage of the phosphorus-sulfur bonds while in photocatalysis, the desulfurization from a P S bond to a P O bond was the primary degradation pathway. Interestingly, only in the UV/TiO 2 process a small fraction of malathion was found decomposed via a demethylation reaction. At the same time, a toxicity assessment of the treated solutions was conducted by both luminescence inhibition of Vibrio fischeri and inhibition of acetylcholinesterase (AChE). It was found that after UV AOP treatment, the toxicity of the malathion aqueous solution increased sharply. In contrast, no increase in toxicity was observed for the malathion aqueous solution after UV alone treatment. This study demonstrates that the high removal efficiency achieved by OPPs does not imply that detoxification of the water solution has been achieved. On the contrary, the toxicity of the treated solutions by OPPs may be increased significantly depending on the selected treatment processes. Image 1 • UV and UV AOPs followed different pathways during degradation byproduct formation. • Toxicity of malathion solution treated by UV AOPs increased with removal efficiency. • Toxicity of malathion solution was relatively unchanged during UV alone treatment. • Formation of malaoxon contributed to AChE toxicity but not to acute toxicity. [ABSTRACT FROM AUTHOR]

Over the last years, there has been a growing interest in the use of Advanced Oxidation Processes (AOPs) for the elimination of micropollutants. This work attempts to compare the efficiency of conventional UV, O 3 and H 2 O 2 based AOPs with a relatively new AOP based on plasma-ozonation, in terms of removal and energy efficiency. The experimental study is performed in a synthetic water matrix spiked with four different micropollutants: atrazine (ATZ), alachlor (ALA), bisphenol A (BPA) and 1,7-α-ethinylestradiol (EE2). For the different processes examined in this study, O 3 – based AOPs are more effective compared to UV based techniques in terms of energy efficiency. Although the energy efficiency of plasma-ozonation falls between the energy cost of O 3 and UV-based AOPs, the removal kinetics generally proceed faster compared to other AOPs, achieving complete elimination (>99.8% removal) of the target compounds within 20 min of treatment. Moreover, the results suggest that improvement in the mass-transfer in the plasma-ozonation setup permits to further decrease the energy cost of this process up to electrical energy per order (EE/O) values between 2.54 and 0.124 kWh m−³, which is already closer to the energy efficiency of ozonation (EE/O = 0.73–0.084 kWh m−³). • Removal of micropollutants from water was studied with different AOPs. • Fastest micropollutant elimination was achieved with plasma-ozonation. • Energy costs decreased in the order: O 3 based AOPs < plasma-ozonation < UV based AOPs. • Mass transfer efficiency plays an important role in performance of plasma-ozonation. [ABSTRACT FROM AUTHOR]

This study investigated the oxidative debromination of 2,2-bis(bromomethyl)-1,3-propanediol (BBMP), a widely used brominated flame retardant, and the corresponding formation of brominated by-products by the UV/persulfate process. The debromination of BBMP by the UV/persulfate process was primarily driven by sulfate radicals (SO 4 −) at pHs 4.0–6.0 and hydroxyl radicals (HO) at pHs 9.0–12.0. The debromination rate increased with increasing pH from 4.0 to 9.0 and remained the same at pHs 9.0 and 12.0. Bromate was formed through the oxidation of bromide released from BBMP mainly by SO 4 −, with free bromine as a key intermediate. Bromate formation increased with increasing pH from 4.0 to 6.0, while it remarkably decreased with increasing pH from 6.0 to 12.0. This was mainly due to the transformation of SO 4 − to HO and also the quenching of bromine atoms that were the key intermediate for the formation of free bromine, by hydroxyl ions at the alkaline pH. In addition, the oxidative debromination of BBMP resulted in a significant decrease in the concentrations of total organic bromine, but the formation of brominated acetic acids and unknown brominated organic by-products. The concentrations of brominated organic by-products firstly increased and then decreased with prolonged reaction time. Also, the formation of brominated organic by-products and genotoxicity at pH 9.0 were much lower than that at pH 6.0. In this study, we propose that the UV/persulfate process under mildly alkaline conditions not only debrominates BBMP efficiently but also eliminates the formation of bromate and brominated organic by-products and genotoxicity. Image 1 • BBMP debromination and brominated by-product formation by UV/persulfate were investigated. • BBMP debromination was mainly driven by SO 4.•− and HO• to form bromide. • Bromate formation involved stepwise oxidation of bromide and then free bromine mainly by SO 4.•−. • Brominated acetic acids and unknown brominated organic by-products were generated. • Alkaline pH increased BBMP debromination and minimized brominated by-product formation and genotoxicity. [ABSTRACT FROM AUTHOR]

Abstract In this study, a bench-scale system was utilized to assess the disinfection byproduct (DBP) formation from human endogenous organic matter. Perspiration and urine, constituting the main organic substances in swimming pools, were selected to represent the major human endogenous organics. Results revealed that the continuous input of body fluids into the reactor led to rapid accumulation of endogenous organic matter, which contributed to high concentrations of DBPs in the swimming pool. The increase in nonpurgeable organic carbon (NPDOC) concentration from the perspiration precursor was lower than that from urine during the operation. Moreover, the accumulation of swimmers' body fluids leads to increased DBP precursors, as well as increased chlorine demand and DBP formation in swimming pool water. The concentration of the trihalomethanes (THMs) and haloacetic acids (HAAs) consistently increased during the reaction. More THMs were generated in urine solution, whereas more HAAs were found in perspiration solution. To improve the water quality in swimming pools, ozonation, UV/Chlorine, and UV/H 2 O 2 treatments were evaluated for their efficacy in reducing the DBP precursors. Results revealed that all of the three treatment processes can degrade the DBP precursors in perspiration and urine, eventually decreasing the DBP concentrations. However, only the UV/H 2 O 2 treatment can decrease the formation of DBPs in perspiration and urine. In addition, the results revealed that UV/Chlorine and UV/H 2 O 2 treatments should be operated for a sufficient contact time to prevent the increased production of DBP precursors in water at the early stage of the treatment. Graphical abstract Image 1 Highlights • DBP formation from endogenous organic matter in swimming pool was assessed. • Continuous input of perspiration and urine led to accumulation of organic matter. • Ozonation, UV/Chlorine, and UV/H 2 O 2 can degrade the DBP precursors in water. • UV/H 2 O 2 can decrease the DBP formation from perspiration and urine. • A longer contact time is needed for UV/Chlorine and UV/H 2 O 2 to reduce DBP precursors. [ABSTRACT FROM AUTHOR]

Abstract In order to develop efficient and green catalyst for organic pollutants removal, magnetic carbon supported Prussian blue nanocomposite Fe 3 O 4 @C/PB was prepared for the first time. The performance of Fe 3 O 4 @C/PB in activating peroxymonosulfate (PMS) for the degradation of 2,4-dichlorophenol (2,4-DCP) was investigated. 2,4-DCP could be effectively degraded under the "Fe 3 O 4 @C/PB + PMS" system within a broad pH range of 2–9. Without pH adjustment (pH 3), 2,4-DCP (20 mg/L) was completely degraded in 50 min along with a 70% removal of TOC; while the required time for complete degradation of 2,4-DCP was shortened to 40 min under initial solution pH at 7. Fe 3 O 4 @C/PB could also activate PMS for the degradation of phenol, Acid Orange II, Reactive brilliant red X-3B, Rhodamine B and Methylene blue. The degradation rates higher than 95% could be achieved for all these contaminants within the time scale of 15–60 min. The studies of radical-quenching and electron paramagnetic resonance demonstrated that singlet oxygen (1O 2) and superoxide radicals (O 2 −), rather than sulfate (SO 4 −) and hydroxyl (OH) radicals, were the dominant species responsible for the oxidation of organic pollutants. The plausible mechanism of the catalytic degradation was proposed and the enhanced activity of Fe 3 O 4 @C/PB was assumed to be related to the increased electron transfer owing to the synergic effect between the magnetic carbon and the mixed-valence units in PB. Fe 3 O 4 @C/PB is promising in wastewater treatment owing to its high efficiency, excellent stability and reusability, environmental friendliness and magnetic separability. Graphical abstract Image 1 Highlights • Magnetic carbon supported Prussian blue nanocomposite was firstly reported. • Fe 3 O 4 @C/PB exhibited high activity for the degradation of 2,4-DCP with PMS. • 1O 2 and O 2 − instead of SO 4 − and OH were dominant ROS in Fe 3 O 4 @C/PB + PMS system. • Fe 3 O 4 @C/PB + PMS system showed general applicability for removing organic pollutants. • The magnetically separable catalyst exhibited good stability and reusability. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are a group of fluorinated organic contaminants classified as persistent in the aquatic environment. Early studies using targeted analysis approaches to evaluate the degradation of PFAS by advanced oxidation processes (AOP) in real water matrices may have been misinterpreted due to the presence of undetected or unknown PFAS in these matrices. The aims of the present study were to (1) screen selected commercially available AOPs (UV, UV + H 2 O 2 , O 3 /H 2 O 2) and UV photocatalysis in a pilot system using commercially used and novel photocatalysts (TiO 2 , boron nitride [BN]) for removing PFAS contaminants and (2) evaluate their role on the conversion of non-detected/unknown to known PFAS compounds in real groundwater used as drinking water supplies. Results indicated that, while AOPs have the potential to achieve removal of the EPA method 533 target PFAS compounds (PFDA [100%], PFNA [100%], PFOA [85–94%], PFOS [25–100%], PFHxS [3–100%], PFPeS [100%], PFBS [100%]), AOPs transformed non-detected/unknown longer-chain PFAS compounds to detectable shorter-chain ones under very high-dose AOP operating conditions, leading to an increase in ∑PFAS concentration ranging from 95% to 340%. As emerging PFAS treatment processes transition from lab-scale investigations of target PFAS to pilot testing of real water matrices, studies will need to consider impact of the presence of non-target long-chain PFAS to transform into targeted PFAS compounds. A promising approach to address the potential risks and unforeseen consequences could involve an increased reliance on adsorbable organic fluorine (AOF) analysis before and after advanced oxidation process (AOP) treatment. [Display omitted] • AOPs transformed non-detected/unknown longer-chain PFAS compounds to detectable shorter-chain ones. • O 3 /H 2 O 2 has the potential to remove PFOA and PFOS up to 85% and 25%, respectively. • UV/BN and UV/BN + TiO 2 degraded PFOA, PFOS, PFHxS, PFPeS, and PFBS in raw groundwater. • Calculated hazard index (HI) values were considerably reduced following UV/BN and UV/BN + TiO 2. [ABSTRACT FROM AUTHOR]

Herein, a novel nitrogen-doped ZnO photocatalyst supported on biochar (N –ZnO@LBC) was synthesized using the Lantana camera as a green source of biochar. The synthesized photocatalyst was applied as an activator of persulfate (PS) for the photodegradation of methylene blue (MB) under visible light irradiation. The properties of the synthesized photocatalyst were explored before and after photocatalysis using different characterization analyses. The results revealed that the nitrogen doping of ZnO@LBC could reduce the band gap energy from 2.83 eV to 2.78 eV resulting in higher activity under visible light. The synergetic effect of the N –ZnO@LBC/PS/visible process was investigated under various reaction conditions. Surprisingly, about 95.7% of MB photodegradation could be achieved using N –ZnO@LBC/PS/visible process under optimal conditions. Moreover, a prediction model with an excellent correlation between the actual and predicted data (R2 = 0.9844) was established to forecast MB removal. Interestingly, the scavenging tests exhibited that various reactive species could induce MB degradation in an order of O 2 −• > h+ > SO 4 −• >•OH with the highest contribution of O 2 −•. Additionally, the presence of functional hydroxyl groups in the N –ZnO@LBC structure could lead to the generation of additional radicals as confirmed by FT-IR analysis after photocatalysis. The reusability test showed that the photocatalyst could be reused for up to five cycles without a significant loss in the photocatalytic activity indicating its high stability. The cost of wastewater treatment by N –ZnO@LBC/PS/Visible process was estimated to be US$ 9.79/m3 based on an economic analysis. It worth mentioning that the proposed process was investigated for the degradation of other dyes including Congo red (CR) and methyl orange (MO) and the efficiencies were 65.41% and 59.23% for CR and MO, respectively. Overall, the proposed process could be a promising and cost-effective approach for the degradation of various dyes in real applications. [Display omitted] • A novel N –ZnO@LBC catalyst was applied for PS activation under visible light. • An excellent prediction model was established. • Various species contributed to MB decay in an order of O 2 −.• > h+ > SO 4 −• >•OH. • N –ZnO@LBC was stable for up to five cycles without significant activity loss. • Wastewater treatment cost was US$9.79/m3. [ABSTRACT FROM AUTHOR]

Quaternary ammonium compounds (QACs) are active ingredients in a palette of commercially available disinfectants, sanitizers, and biocides. QACs are widely used because of their broad-spectrum antimicrobial properties but the ubiquitous uses have resulted in frequent detection in aquatic and terrestrial matrices including domestic wastewater, surface waters, urban soils and sediments. An increased domestic QACs consumption has increased the environmental occurrence, and investigation of mitigation methods and effects on non-target organisms are in demand. In this study, we examined the potential ecotoxicity of six QACs and investigated the effect of combined vacuum UV (185 nm) and UV-C (254 nm) irradiation (VUV/UVC) on degradation and mitigation of ecotoxicity of QACs. The study showed that combined VUV/UVC irradiation facilitated rapid degradation of benzalkonium chloride, benzethonium chloride, didecyldimethylammonium chloride, dodecyltrimethylammonium chloride, and hexadecyltrimethylammonium chloride. The estimated half-lives varied between 2 and 7 min, and degradation was affected by the initial QAC concentrations, the UV fluence, and the water matrix. The potential ecotoxicity of QACs and VUV/UVC treated QACs was examined using a battery of test organisms that included the luminescent bacterium Aliivibrio fischeri , the gram-negative and gram-positive bacteria Escherichia coli and Enterococcus faecalis , the freshwater microalga Raphidocelis subcapitata , and the crustacean Daphia magna. The potential for trophic transfer of QACs was investigated in a simplified aquatic food web. Test organisms from different trophic levels were included to assess adverse effects of bioactive compounds in VUV/UVC treated samples including transformation products. The study showed that several QACs were highly toxic to aquatic test organisms with EC50 and/or EC20 values < 1 μM. VUV/UVC treatment of QACs resulted in substantial photolysis of the parent compounds and comprehensive mitigation of the ecotoxicity potential. VUV/UVC represent an attractive oxidation technology for abatement QACs in contaminated water because the process does not require addition of catalysts or precursors. [Display omitted] • QACs exhibit high toxicity to aquatic organisms and a potential for trophic transfer. • VUV/UVC irradiation rapidly degrades QACs within minutes. • VUV/UVC irradiation can mitigate the ecotoxicity of QACs. • VUV/UVC oxidation is an effective technology without requiring catalysts. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) in aquatic environments are threatening ecosystems and human health. In this work, an effective and environmentally friendly catalyst based on biochar and molecular imprinting technology (MIT) was developed for the targeted degradation of PAHs by activating peroxymonosulfate. The results show that the adsorption amount of naphthalene (NAP) by molecularly imprinted biochar (MIP@BC) can reach 82% of the equilibrium adsorption capacity within 5 min, and it had well targeted adsorption for NAP in the solution mixture of NAP, QL and SMX. According to the comparison between the removal rates of NAP and QL by MIP@BC/PMS or BC/PMS system in respective pure solutions or mixed solutions, the MIP@BC/PMS system can better resist the interference of competing pollutants (i.e., QL) compared to the BC/PMS system; that is, MIP@BC had a good ability to selectively degrade NAP. Besides, the removal rate of NAP by MIP@BC/PMS gradually decreased as pH increased. The addition of Cl− greatly promoted the targeted removal of NAP in the MIP@BC/PMS system, while HCO 3 − and CO 3 2− both had an inhibitory effect. Furthermore, SO 4 •-, O 2 •- and 1O 2 produced by BC activating PMS dominated the NAP degradation, and it was inferred that the vacated imprinted cavities after NAP degradation can continue to selectively adsorb NAP and this could facilitate the reusability of the material. This study can promote the research on the targeted degradation of PAHs through the synergism of biochar/PMS advanced oxidation processes and MIT. [Display omitted] • Molecularly imprinted polymers (MIP) and advanced oxidation processes were coupled. • Biochar (BC) applied in activating peroxymonosulfate (PMS) was upgraded using MIP. • The MIP@BC/PMS system can well selectively degrade naphthalene (NAP). • Mechanisms controlling the targeted degradation of NAP were elucidated. • The occurrence of Cl− promoted the targeted removal of NAP in the MIP@BC/PMS system. [ABSTRACT FROM AUTHOR]

Residual flotation chemicals in beneficiation wastewater seriously threaten local ecosystems, such as groundwater or soil, and must be treated effectively. Currently, the degradation of organic pollutants using nitrided MOFs-derived carbon to activate persulfate (PDS) has attracted considerable attention. Hence, we developed a new synthetic strategy to load dopamine hydrochloride (PDA) onto MOF-5-derived porous carbon (PC) to form NPC, and the degradation of a typical flotation Aniline aerofloat (AAF) at high salinity by a low dose of the NPC/PDS system was investigated. Several characterization analyses such as TEM, XRD, Raman, FT-IR and XPS demonstrated that the nitrogen-rich indolequinone unit in PDA provided nitrogen to PC during the pyrolysis process. This enabled the core-shell structure of NPC and the synergy among the multiple components to induce the AAF degradation by PDS over a wide pH scale in a short period of time. It was deduced that the degradation of AAF by the NPC-8/PDS system was a non-radical pathway dominated by 1O 2 , which relied mainly on the conversion of superoxide radicals (O 2 •−) and surface-bound radicals. Among them, the pyridine N in the sp2 hybrid carbon was considered as a possible active site. This non-radical pathway was resistant to pH changes and background substances in the water, and well overcame the inhibition of the reaction by natural organic substances and inorganic anions in natural water. In this study, A novel approach to the synthesis of homogeneous MOFs nuclear-derived porous carbon was proposed and the application of MOFs-derived porous carbon for AAF remediation of mineral processing wastewater was broadened. [Display omitted] • A novel synthesis strategy for MOFs nuclear-derived porous carbon was proposed. • The 1O 2 and carbon bridging oxidation in NPC-8/PDS system was examined. • 1O 2 relies mainly on the conversion of superoxide radicals (O 2.•−) and surface bound radicals. • The pyridine N in the sp2 hybrid carbon was proposed as a possible active site. • The NPC-8/PDS system degrades AAF with less interference from (in)organics. [ABSTRACT FROM AUTHOR]

This paper reports the optimization of the electro-Fenton (EF) process using different anode materials for the degradation of Methylene Blue (MB) dye as a model compound. The cathode used was an air-diffusion PTFE, while three different anode materials (Pt, DSA, and self-doped TiO 2 nanotubes - SD-TNT) were tested individually. A full factorial design (FFD) with a central point combined with response surface methodology (RSM) was employed to optimize the experimental variables, including solution pH, applied current, and anode material. The optimized EF conditions involved a pH of 4.0, a current of 100 mA, and an SD-TNT anode for 120 min of electrolysis. Under these conditions, the MB solution achieved complete decolorization and 45% of total organic carbon (TOC) removal after 120 min of EF treatment. The findings indicate that the hydroxyl radical (•OH) plays a crucial role as the primary oxidizing agent in the EF process. The decay of MB followed pseudo-first-order kinetics, reflecting a consistent formation of •OH radicals that effectively attacked the MB dye and its subproducts during mineralization. Moreover, the EF process exhibited superior performance in terms of energy consumption (EC) and mineralization current efficiency (ECM) in the initial treatment stages, while the presence of recalcitrant by-products and loss of anode self-doping impacted performance in the later stages. The optimized EF conditions and the understanding gained from this study contribute to the advancement of sustainable wastewater treatment strategies for the removal of organic dyes. [Display omitted] • Enhanced Methylene Blue (MB) degradation by optimized electro-Fenton (EF). • EF optimization with response surface methodology (RSM) for higher efficiency. • Self-doped TiO 2 nanotube (SD-TNT) anode enhances MB decolorization. • Fast MB decolorization is achieved in only 15 min with EF treatment. • The key role of.•OH radicals as primary EF oxidizing agents revealed [ABSTRACT FROM AUTHOR]

Single-atom catalysts have been proved to be an effective material for the removal of organic pollutants from water and wastewater, and yet, the relationship between their internal structures and their roles still remains elusive. In this work, a catalyst Fe (MIL)-SAC with single-atom Fe–N 4 active site was prepared. Fe (MIL)-SAC/Peroxydisulfate (PDS) system was able to achieve complete degrade of the Sulfamethoxazole (SMX) with k obs at 0.466 min−1, which was faster than the Fenton system under the same conditions (k obs = 0.422 min−1) and 16 times faster than Fe (MIL) (k obs = 0.029 min−1). Density functional calculations reveal that the Fe–N 4 structure will affect the electron transport path and lead to selective generation of 1O 2 by triggering S–O breakage and O–O polarization in PDS. Furthermore, Fe (MIL)-SAC/PDS system exhibits strong resistance to common influencing factors and has good application prospects. This work provides a new approach for the selectively generation of 1O 2 for the efficient treatment of organic pollutants in aqueous environment. [Display omitted] • Electron enrichment at Fe sites induced by polarized electric fields. • Singlet oxygen was proved to be the only reactive oxygen species. • The degradation efficiency of SMX was 16 times improvement. • The Fe (MIL)-SAC catalyst exhibited a high stability under different conditions. • The reason and mechanism of selectivity generate singlet oxygen was systematacially investigated. [ABSTRACT FROM AUTHOR]

Abstract In the present study, stabilized landfill leachate treatment by heterogeneous Fenton and electro-Fenton (EF) was carried out. Iron-manganese binary oxide loaded zeolite (IMZ) was used as a catalyst for generating hydroxyl radicals in the acidic medium. Heterogeneous Fenton process was capable of removing 88.6% COD from landfill leachate at the optimal conditions, while 87.5% COD removal was observed at optimal EF treatment conditions. Biodegradability of landfill leachate was increased significantly from 0.03 to 0.52 after Fenton treatment. The prepared heterogeneous catalyst was found reusable with a reduction in COD removal rate. Even though, both the processes are efficient for leachate treatment, the low catalyst dosage requirement in case of EF process justifies that it is more feasible than Fenton process. Highlights • Effective treatment of stabilized landfill leachate by Fenton and electro-Fenton. • Iron-manganese binary oxide loaded zeolite is an efficient heterogeneous catalyst. • Enhancement in biodegradability of leachate after treatment. [ABSTRACT FROM AUTHOR]

Aeration-assisted non-thermal plasma (NTP) process is known as promising due to simultaneous generation of oxygen- and nitrogen-based reactive chemicals for non-biodegradable pollutants removal in a wastewater. Despite its effective oxidizing capability, the decomposition mechanism of antibiotics is not yet clarified well. This study verifies the NTP's removal potential of non-biodegradable sulfonamide antibiotics in the treatment of strong wastewater. The instantaneous production of hydrogen peroxide (H 2 O 2 ) was quantified to prove synergistic advanced oxidation, and degradation kinetic coefficients of N, N-Dimethyl-4-nitrosoaniline (RNO) reveals rapid oxidation rate of NTP. Also, the results of an acute-toxicity test using Daphnia magna demonstrate how the toxicity of antibiotics intermediates responds to the NTP. Results indicate that the NTP has better potential than conventional oxidation processes in terms of OH-radical generation due to the interplay of reactive species. This study provides useful information that aeration-assisted NTP application to wastewater treatment can be a viable option to enhance treatment efficiency via plasma-related reactive species and that how environmental ecotoxicity responds to the by-products of sulfonamide antibiotics. [ABSTRACT FROM AUTHOR]

Catalytic membrane, due to its compact reactor assembling, high catalytic performance as well as low energy consumption, has proved to be more attractive for wastewater treatment. In this work, a free-standing α-MnO 2 @CuO membrane with hierarchical nanostructures was prepared and evaluated as the catalytic membrane to generate radicals from peroxymonosulfate (PMS) for the oxidative degradation of organic dyes in aqueous solution. Benefiting from the high mass transport efficiency and the hierarchical nanostructures, a superior catalytic activity of the membrane was observed for organic dyes degradation. As a typical organic dye, more than 99% of methylene blue (MB) was degraded within 0.23 s using dead-end filtration cell. The effects of flow rate, PMS concentration and buffer solution on MB degradation were further investigated. Besides MB, the catalytic membrane also showed excellent performance for the removal of other dyes, such as congo red, methyl orange, rhodamine B, acid chrome blue K and malachite green. Moreover, the mechanism study indicated that OH and SO 4 - generated from the interaction between PMS and Mn/Cu species with different oxidation states mainly accounted for the dyes degradation. The catalytic filtration process using α-MnO 2 @CuO catalytic membrane could provide a novel method for wastewater purification with high efficiency and low energy consumption. [ABSTRACT FROM AUTHOR]