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[Display omitted] • Highly dispersed CeO x decorated mesoporous silica promotes Ni-catalyzed CO 2 methanation. • The catalyst exhibits a 3-fold increase in activity and enhanced CH 4 selectivity compared to the Ce-free catalyst. • The oxygen vacancy sites contributed by CeO x present high adsorption and dissociation ability of CO 2. • The in-situ FT-IR and kinetic isotope results indicate that CO 2 activation is the rate-determining step of the reaction. CO 2 methanation is a key step in the power-to-gas technology for storing and distributing renewable energy as energy vectors. Due to thermodynamic constraints, highly active catalysts below about 300 °C are necessary. We demonstrate that their preparation is possible by supporting Ni nanoparticles over highly dispersed CeO x species decorating mesopores silicate (mSiO 2) obtained by a template-free method. The CeO x decorated mSiO 2 exhibits a 3-fold increase in activity and enhanced CH 4 selectivity (98.7 % at 300 °C) compared to the Ni/mSiO 2 catalyst. The performances are superior compared to the literature data. A systematic characterisation by physisorption, XPS, XAFS, UV–Vis and HR-TEM shows a uniform dispersion of highly dispersed CeO x within the mesoporous silica framework. The CO 2 hydrogenation properties were investigated in a fixed-bed flow reactor and complemented by CO 2 -TPD, CO 2 -TPSR, in-situ FTIR, and D 2 kinetic isotope experiments. The results show that highly dispersed CeO x exhibits excellent CO 2 adsorption and dissociation abilities. The inverse kinetic isotope effect indicates that CO 2 activation is the rate-determining step of the reaction. CO 2 is strongly adsorbed on CeO x to form bidentate carbonate, which accelerates the generation of CO while avoiding the adsorption of CO 2 on Ni nanoparticles. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Chloride positive/negative impact on UV/PMS process is analyzed quantitatively. • Nitrate impact on photoproduction of HO and SO 4 − is PMS concentration dependent. • Radical termination rate instead of concentration quantifies radical conversion. • Radical participation ratio is deduced as an index to quantify radical selectivity. Abstract In this study, we examined chloride impact on UV/peroxymonosulfate (UV/PMS) process with benzoate acid (BA) and chloroform (TCM) as target compounds, which react rapidly and slowly with HO and SO 4 −, respectively. The chloride impact on UV/PMS process in simulated real water (mixture of nitrate, carbonates, natural organic matter (NOM) and chloride) was analyzed based on the individual impact of anions and NOM. Pseudo steady-state and dynamic kinetic models were developed to calculate radical concentrations and determine the roles of water matrix in BA and TCM degradation. Radical conversion and radical selectivity were proposed to be quantified by radical termination rate and radical participation ratio (RPR). The latter one indicated the radical participation between target compound and other radical termination species coexisted. Chloride stimulating or inhibiting target compound destruction, due to radical conversion induced by chloride concentration variation, was deduced to depend on the RPR difference of conversion radicals. Nitrate affected target compound destruction rate by two aspects, radical conversion (similar to the role of chloride) and total photoproduction rate of HO and SO 4 −. The total photoproduction rate of radicals showed a PMS-concentration involved dependence on nitrate concentration. Nitrate enhanced total photoproduction rate at low PMS concentration and reduced the rate at high PMS concentration. In simulated real water, carbonates played the key role in radical conversion and RPR. The coexistence of carbonates and chloride converted most SO 4 − into Cl 2 − and Cl, leading to an obvious inhibition of chloride on BA degradation. [ABSTRACT FROM AUTHOR]

Four magnetic spinel ferrite MFe 2 O 4 (M = Co, Cu, Ni and Zn) were successfully prepared by the auto combustion reaction method and applied to catalyze ozone for treating the practical shale gas produced water (PW). This typical bio-refractory produced water was processed into a good biodegradability one. The catalytic performance of them was ranked as CuFe 2 O 4  > NiFe 2 O 4  > CoFe 2 O 4  > ZnFe 2 O 4 . The B[Spsbackslash]C ratio was promoted from less than 0.1 to over 0.3, and the AOC concentration was improved 5 times, and AOC[Spsbackslash]TOC ratio could reach 8%. The bio-toxicity was decreased significantly which was evaluated by the EC 50 of Photobacterium phosphoreum T3 and the growth inhibition ratio of E. coli , and it was decreased significantly. With the help of Scatchard model and Weber-Morris model, the results illustrated that the catalytic performance depended on surface property, and a suitable surface property could be an advantage in catalytic oxidation for degrading high concentration organic wastewater. The four MFe 2 O 4 all presented a good recycling performance. This study provided a significant insight into the rational design and the advisable practice application of heterogeneous catalysts for dealing with shale gas produced water. [ABSTRACT FROM AUTHOR]

• A novel framework was firstly proposed for identifying the gene-degrading intermediates. • The gene-degrading intermediates would tend to have the abundant GGC motifs and relatively high GC content. • The breakpoints of gene-degrading intermediates show preference of guanine base. • The as-prepared material exhibited as a promising candidate for removal of ARB and ARGs in aquatic environment. Antibiotic resistance bacteria (ARB) and antibiotic resistance genes (ARGs) have been recognized as emerging pollutants. It is accessible to restrict disseminating antibiotic resistance by inactivating ARB and degrading its ARGs by oxidation treatment processes in aquatic environment, but until now the producing gene-degrading intermediates are not reported. In this study, a novel post-pyrolysis bio-hybridcarbon (Co@PS-BC) was prepared for peroxymonosulfate (PMS) activation to eliminate both E. coli DH5α-based ARB and its ARGs (bla TEM-1 and NPTII). Importantly, gene-degradation intermediates of ARGs were analyzed by Nanopore sequencing and Illumina sequencing. The results of bioinformatic analyses showed that the gene-degrading intermediates held the abundant GGC motifs, relatively high GC content and base preference of breakpoints toward guanine. Overall, our work develops a novel approach for effectively eliminating ARB and ARGs from water, and provides an insight into the composition and base preference of gene-degrading intermediates. [ABSTRACT FROM AUTHOR]

Titanate nanotubes (TNTs) have been shown effective for adsorption of heavy metals due to large specific surface area and outstanding ion-exchange property. However, the adsorption capacity is severely suppressed in the presence of natural organic matter (NOM) due to TNTs’ poor interactions with NOM. In this study, powder activated charcoal supported TNTs (TNTs@PAC) were synthesized through a one-step hydrothermal method, and tested for adsorption of Pb(II) in the presence of high concentrations of NOM. TNTs@PAC showed both rapid adsorption kinetics, and high capacity for Pb(II), as well as strong resistance to NOM. Most adsorption occurred in the first 60 min, and the maximum Langmuir capacity of Pb(II) was determined to be 318.5 mg/g. Notably, a model humic acid (HA) showed negligible effect on Pb(II) adsorption. The primary adsorption mechanism was demonstrated to be ion exchange between Pb(II) and interlayered Na + in TNTs, and, in the presence of humic acid, interactions between PAC and the NOM-Pb complexes. The spent material can be easily regenerated and reused for multiple Pb(II) adsorption cycles. The excellent adsorption performance combined with high NOM-resistance make TNTs a promising nanomaterial for remediation of heavy-metals contaminated waters. [ABSTRACT FROM AUTHOR]

• Fabrication of slippery coating without loss of lubricant. • The resistance to the loss of lubricants. • Quantum chemical calculation of interaction energy between silicone oil and polyorganosilazane molecules. • The better anti-icing and anti-corrosion ability. Inspired by Nepenthes pitcher plant, slippery liquid-infused porous surface (SLIPS) has been received great concern. However, the fabrication and application of SLIPS generally cannot avoid the complicated construction of the micro/nanostructures and the loss of the lubricant. In addition, despite another slippery covalently surface can exhibit liquid-like properties of SLIPS, the chemical grafting reaction conditions are usually harsh and low-efficiency. To address these challenges, herein an easy, high-efficiency and non-fluorinated strategy to create a flat slippery coating without the loss of lubricant (SCLL) was reported. The better flatness and the own hydrophobicity of the cured polyorganosilazane (PSZ) combined with the silicone oil molecules on its surface endowed the SCLL excellent slippery property. Moreover, the strong intermolecular attraction and the large adhesion work originated from the chemical affinity between PSZ and silicone oil molecules allowed the proposed SCLL with no lubricant loss. We further showed the SCLL has promising application prospects in the ice resistance, indicated by its longer icing-delaying time and lower ice adhesion strength, compared with original Al surface. Our envision is that SCLL may be applied in the practical industry production. [ABSTRACT FROM AUTHOR]

Ultraviolet/persulfate (UV/PS) has been widely used to generate sulfate radicals (SO 4 − ) in degrading organic pollutants. However, its impact on chlorinated disinfection byproducts (DBPs) is unclear. Impact of UV/PS pretreatment on the formation of DBPs during subsequent chlorination of natural organic matter was evaluated in this study. For the samples pretreated by UV/PS, the formation of some carbonaceous disinfection byproducts (C-DBPs) such as chloroform and haloacetic acids only increased a little, but the formation of nitrogenous disinfection byproducts (N-DBPs) including haloacetonitriles and trichloronitromethane decreased slightly. UV/H 2 O 2 pretreatment increased the formation of both C-DBPs and N-DBPs significantly with the initial dosage of H 2 O 2 being 30 μM. Chloral hydrate and haloketones followed an increasing and then decreasing pattern, but dichloroacetonitrile and trichloronitromethane followed an opposite pattern with increasing UV/PS pretreatment time. Most of the C-DBPs rose monotonically with increasing dosages of PS, but N-DBPs declined at the dosage of PS being 10 μM by UV/PS pretreatment. Preoxidation pH and the presence of nitrate played little role in DBP formation. In the presence of 2.5 mg/L ammonia, UV/PS pretreatment increased most of the DBPs except for trichloroacetonitrile and trichloronitromethane. Bromine incorporation factors for trihalomethanes, haloacetic acids and dihaloacetonitriles were affected by UV/PS preoxidation insignificantly. It is suggested that the combination of UV/PS and post chlorination was expected to be a good choice in controlling the formation of DBPs. [ABSTRACT FROM AUTHOR]

Highlights: [•] Facile method: The catalysts were synthesized by facile hydrothermal method without any templates. [•] Good properties: 20BBM exhibits the best property of degradations of 2,4-DNP among the reported catalysts. [•] Effect of H2O2: H2O2 improving the activity of photodegradation of 2,4-DNP is firstly demonstrated. [•] New mechanism: New photocatalytic mechanisms for the heterostructured composites are proposed. [Copyright &y& Elsevier]

[Display omitted] • BQ improved efficiency of the Fe(III)/PMS system via boosting Fe(II) regeneration. • SO 4 •−, •OH and Fe(IV) simultaneously existed in the BQ/Fe(III)/PMS system. • Activation mechanism was clarified and degradation pathways were proposed. • Cl− inhibited ATZ degradation and caused chlorinated byproducts accumulation. Fe(II)-involved advanced oxidation processes could effectively degrade refractory contaminants, but the slow transformation of Fe(III) to Fe(II) limits their wide application. Herein we reported that p -benzoquinone (BQ) could accelerate Fe(III)/Fe(II) cycle and promote atrazine (ATZ) degradation in the Fe(III)/peroxymonosulfate (Fe(III)/PMS) system through reconstructing active Fe(II)/PMS system. Under the identical experimental conditions, ATZ degradation efficiency in the BQ/Fe(III)/PMS system (99.8%) was superior to that in the Fe(III)/PMS system (23.2%), suggesting the indispensable role of BQ in Fe(II) regeneration and PMS activation. Reactive species sulfate radical (SO 4 •−), hydroxyl radical (•OH) and ferryl ion (Fe(IV)) were involved in the BQ/Fe(III)/PMS system based on alcohol quenching experiments, ESR tests and the selective transformation from methyl phenyl sulfoxide (PMSO) to methyl phenyl sulfone (PMSO 2). ATZ degradation mechanism was proposed based on LC-MS detection, among which dealkylation and dechlorination-hydroxylation were the dominant transformation pathways. The BQ/Fe(III)/PMS system showed satisfactory catalytic performance at pH 2.5–7.0 and low Fe(III) concentration, which expanded the pH range and avoided the addition of a large amount of Fe. More importantly, the increase of PMS concentration not only enhanced the oxidative degradation of ATZ and its two main chlorinated byproducts (atrazine-desethyl (DEA) and atrazine-desisopropyl (DIA)), but also facilitated the removal of toxic BQ. Cl− inhibited the degradation of ATZ and caused the accumulation of DEA and DIA, and the higher Cl−, the more obvious this effect. This study provided a new approach to improve the Fe(III)/PMS system by boosting Fe(III)/Fe(II) cycle with quinons. [ABSTRACT FROM AUTHOR]

The well-designed heterostructured CoP/CN/Ni with oriented electron transfer from the inner Ni to the outer CoP shows excellent electrocatalytic hydrogen evolution and oxygen reduction performances. [Display omitted] • Electronic structure of outer CoP is modulated by the electrons from Ni through CN. • The value of ΔG H* on electron modulated CoP decreases from −0.25 eV to −0.1 eV. • CN layer protects the inner Ni from oxidation and corrosion in harsh environment. • Enriched electrons around CoP weakens its surface oxidation at high potential. Cobalt phosphide (CoP) with its platinum-group-metal like catalytic features has triggered substantial concerns on electrocatalytic hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) under acidic and alkaline conditions. However, the electrocatalytic rate on CoP is restricted because of the reaction intermediates binding to its surface strongly, leading to sluggish reaction kinetics and unsatisfied catalytic performance. Herein, we describe a ternary heterostructured CoP/CN/Ni catalyst with oriented electron modulation effect to boost its electrocatalytic activity, where the electronic structure of the outer CoP is modulated by the endowed electrons from underlying Ni nanoparticles, which are encapsulated and protected by 2–3 N-doped carbon (CN) layers from oxidation and corrosion in harsh environment. Theoretical calculations reveal that the electron redistribution effect could decrease the adsorption energy of hydrogen (ΔG H*) on CoP from −0.25 eV to −0.1 eV. Benefiting from such electron modulation, CoP/CN/Ni only needs overpotentials of 66 mV in 0.5 M H 2 SO 4 and 106 mV in 1 M KOH for HER to afford a current density of 10 mA cm−2 and presents the comparable ORR activity with Pt/C in 0.1 M KOH. Besides, the unique structure also endows CoP/CN/Ni with superior electrocatalytic stability for HER and ORR. [ABSTRACT FROM AUTHOR]

The PE separator modified by double-coated nano-sized LLZTO is developed. Benefiting from the double-coated nano-sized LLZTO layer's enhancement to thermal stability and it can guide the uniform deposition of lithium ions and suppress the growth of lithium dendrites, an excellent electrochemical performance could be achieved in the lithium symmetric cell and lithium metal batteries. [Display omitted] • The PE separator modified by double-coated nano-sized LLZTO is developed. • The nano-sized LLZTO improves the thermal stability of the PE separator. • It can also guide the uniform Li ions deposition and suppress Li dendrites lithium. • Symmetric and full cells with LLZTO-coated separator exihibit an excellent performance. Lithium metal batteries, as one of high-energy-density batteries, have become the hot spot for numerous researchers. However, serious safety problems caused by lithium dendrites need to be urgently addressed. In this work, we introduce nano-sized garnet solid-state electrolyte Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 (LLZTO) to fabricate a high-safety thin composite solid electrolyte membrane (20 μm) that is simple in process and facile in preparation conditions. The thin composite solid electrolyte film has better wrinkle resistance than ordinary polyethylene (PE) films and can guide the uniform deposition of lithium ions and suppress the growth of lithium dendrites. The thermal stability of the PE separator modified by double-coated nano-sized LLZTO is enhanced, which exhibits only 30 % shrinking percentage at 140 °C in comparison with 90 % of ordinary PE. The lithium symmetric cell with the nano-sized garnet solid-state electrolyte modified separator is relatively stable after 1000 h cycling at the current density of 1 mA cm−2. More importantly, after adding the adaptable electrolyte, the lithium metal battery assembled with modified separator can be maintained for 150 cycles (0.2C) stably with a high cathode active material loading of NCM811 (18 mg cm−2), and can maintain above 95 % Coulombic efficiency on average. Our work provides a pathway for the preparation of superior thermal stability and high safety garnet-based composite membranes towards lithium metal batteries. [ABSTRACT FROM AUTHOR]

• Structure-reactivity relation of Ni 1-x Fe x (OH) 2 was elucidated at electronic level. • Chromium substitution was predicted as a promoter for OER by computational data. • Ni 1-x-y Fe x Cr y (OH) 2 with superior activity was synthesized based on DFT prediction. • Electronic coupling strategy provides a principle for screening efficient catalyst. Developing low-cost yet highly efficient earth-abundant electrocatalysts for oxygen evolution reaction (OER) is of great significance for industrial scale water splitting for clean hydrogen production, as well as for rechargeable metal-air batteries. In searching for advanced catalysts, it is equally important to fundamentally understand working mechanism and be able to rationally design and manipulate catalytic sites. Starting from the density functional theory (DFT) calculations as a guidance, our theoretical model revealed that chromium substitution in nickel–iron hydroxides (Ni 1-x Fe x (OH) 2) not only accelerated the charge transfer but also regulated the adsorption energy of OER intermediates to achieve optimal binding strength. Experimentally, chromium was doped into the laminate of Ni 1-x Fe x (OH) 2 , resulting in the enhanced catalytic performance for oxygen evolution reaction, which confirmed the predictions from the theoretical data. The porous and ultra-thin ternary Ni 1-x-y Fe x Cr y (OH) 2 electrocatalysts were grown directly on a nickel foam (NF) substrate, with an optimum composition Ni 0.66 Fe 0.27 Cr 0.07 (OH) 2 /NF identified, which exhibited a superior OER performance, i.e., achieving a significant current density of 10 mA cm−2 at a low overpotential of 231 mV, a small Tafel slope (31 mV dec−1) and an excellent stability at a highly oxidative potential of 1.68 V vs RHE in alkaline electrolyte. The comprehensive study involving both theoretical and experimental results in this work provides an insightful guidance in designing efficient OER catalysts for chemical and electrical energy conversion and storage. [ABSTRACT FROM AUTHOR]

• A novel oxygen-containing demulsifier has been designed and synthesized. • The demulsifier contains ester group, carboxyl group and ether bond simultaneously. • The demulsifier could completely break the W/O emulsions, even asphaltene-stabilized emulsions. • Over 97% of the interfacially active asphaltene (IAA)-stabilized emulsions could be demulsified in less than 15 min. A novel aliphatic alcohol nonionic polyether (MJTJU-2) has been successfully synthesized by esterification and polymerization. It is found that this new polyether is efficient in fast demulsifying the water-in-oil emulsions, including water-in-diesel emulsion, water-in-crude oil emulsion, water-in-asphalt oil emulsion and water-in-asphaltenes solution emulsion, etc. Take the most stable emulsion (interfacially active asphaltene (IAA)-stabilized emulsions) as an example, almost complete dehydration (>97%) to the emulsions could be achieved in less than 15 min at 60 °C using 400 ppm of MJTJU-2. This demulsification of IAA-stabilized emulsions is much faster than other reported work by traditional or commercial demulsifiers (up to several hours). To comprehensively understand how the MJTJU-2 influence the demulsification efficiency, the operational parameters (e.g., demulsifier dosage, temperature, settling time) have been systematically investigated and optimized. The excellent performance of MJTJU-2 in demulsifying the oil-water emulsions is considered mainly to be ascribed to the rich hydrophilic groups (i.e., hydroxyl, ester groups, carboxyl groups, ether groups) in the demulsifier molecules. These oxygen-containing groups help to break the IAA-formed film at the oil-water interface, which would be replaced by newly formed bonding. These findings suggest that the MJTJU-2 demulsifier would be potential engineering efficient process aids for the demulsification of water-in-oil emulsions. [ABSTRACT FROM AUTHOR]

• Lignin incorporated into starch-based liquid mulch became a pseudoplastic fluid. • Pseudoplastic liquid mulch was easily sprayed and formed a complete film on soil. • Prepared LSA liquid mulch increased the content of available soil nitrogen. • Chinese cabbage yield was increased using the LSA mulch with slow-release urea. Because traditional slow-release fertilizers cannot effectively retain soil heat and moisture, their ability to increase crop yields is limited. To solve this problem, novel sprayable liquid mulch films (lignin-starch-acrylate, LSA) were prepared with a slow-release urea function, created by emulsion polymerization between lignin (extracted from papermaking waste liquor), starch, and acrylate monomers. The introduction of lignin transformed the LSA emulsion into a pseudoplastic fluid with enhanced sprayability. The presence of lignin in LSA film increased the elongation at break and lowered the Young's modulus, resulting in a film that is more easily pierced by crop seedlings and preserves the heat and moisture of the soil after seedling piercing. Experimental results showed that at a mass ratio of lignin to acrylate monomers of 3/7, the LSA mulch film had good sprayability and film-forming properties, suitable mechanical properties, and the lowest urea release rate. This optimized LSA film exhibited better soil insulation and water retention performance than other slow-release fertilizers. The contents of available soil nitrogen, including NH 4 +-N and NO 3 −-N, in soil covered with LSA film were 44.82 and 45.49% higher than those in soil covered with urea, respectively, and the corresponding cabbage yields increased by 33.73%. The results of this study provide a new method for preparing agricultural materials with urea slow-release as well as soil moisture and heat preservation functions. [ABSTRACT FROM AUTHOR]

[Display omitted] • rSBR improve sulfate removal by upregulating dissimilated sulfate reductase. • Bioaugmentation with immobilized rSBR accelerates the metabolism of sulfate. • rSBR remove heavy metals via coprecipitation. • Bio-AnMBR removes approximately 99.4% of sulfate and 95.6% of metal removal. Sulfate-rich metal-laden wastewater (SRMLW) shows a significant threat on the ecological environment and human health. Sulfate-reducing bacteria (SRB) can remove sulfate from wastewater in anaerobic membrane bioreactor (AnMBR). This study constructed recombinant genetic engineered SRB (rSRB) and investigated the sulfate and heavy metals removal efficiency for treating SRMLW by immobilized-microbial bioaugmentation using rSRB (IMrSRB) coupled with AnMBR (Bio-AnMBR). The results show that Bio-AnMBR removed sulfate (99.4%) from SRMLW by upregulating key genes (Sat , DsrAB , AprAB , QmoABC , DsrC and DsrMKJOP) and enzymes (APS reductase, Dissimilatory sulfite reductase, Trithionate reductase and Thiosulfate reductase) in dissimilatory sulfite and sulfate respiration processes. Bio-AnMBR achieved synergistic biodegradation of sulfate and nitrogen by stimulating the activity of these bacteria related to the conversion of nitrogen and sulfate. Microbial analysis indicated that the relatively high abundance of rSRB (79.2%) and functional genes (70.1%) upregulated the activities of key enzymes associated with sulfate metabolism system, thus increasing the production of S (66.4 mg/L) and H 2 S (23.8 mg/L). Bio-AnMBR significantly improved the tolerance to heavy metals by increasing concentrations of CO32–, S2-, and HS-, which was configured to reduce heavy metals (95.6%) via precipitation of metal sulfide (81.3 mg/L), metal carbonates (30.7 mg/L) and metal hydroxides (18.7 mg/L). Bio-AnMBR increased system stability, shorted hydraulic retention time (HRT), decreased the production of soluble microbial products (SMP), extracellular polymeric substances (EPS) and waste-sludge production (WSP), as well as improved effluent quality. In conclusion, data in this study indicate that application of Bio-AnMBR is a feasible strategy for the treatment of SRMLW. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Catalytic ozonation of atrazine on tourmaline was studied. • Tourmaline exhibited superior catalytic performance even in low temperature (278 K). • Surface properties of tourmaline was characterized in detail. • 31 kinds of intermediates were identified and the degradation pathways of atrazine were proposed. Abstract Tourmaline, an economical and eco-friendly natural mineral, has been widely used during the water treatment processes. In this investigation, the raw tourmaline has been found to be effective as a catalyst for ozonation in the degradation of atrazine (ATZ) under low temperature (278 K). Within typical experimental conditions (tourmaline dosage = 1 g L−1, [ATZ] 0 = 5 μM, [O 3 ] 0 = 3 mg L−1, at pH 7.0 and 278 K), the removal efficiency of ATZ in catalytic ozonation was 98% after 10 min, compared with only 27% ATZ removal in the absence of catalyst. Surface properties and components of tourmaline were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectra (FTIR), pyridine-FTIR and energy dispersive X-ray (EDX). The characterization studies showed that metal attached hydroxyl groups (M OH, M = Fe, Al and Si) were the main active sites for ozone adsorption and decomposition. The formation of hydroxyl radicals (OH) as well as hydrogen peroxide (H 2 O 2) led to fast ATZ degradation and 31 kinds of intermediates; meanwhile, possible degradation pathways of ATZ were detected and proposed. The mechanisms of reaction were proposed for tourmaline-catalyzed ozonation based on all the experimental results and material characterizations. [ABSTRACT FROM AUTHOR]

This study showed that substituted anilines of environmental concerns could be appreciably degraded by potassium ferrate (K 2 FeO 4 ) in the pH range of 6–10 with apparent second-order rate constants ( k app ) varying from 0.32 to 36,500 M −1 s −1 . The pH-dependence rate curves were well fitted via a kinetic model, which involved the formation of intermediates between Fe(VI) and substituted anilines. The plausible degradation pathways were proposed including the generation of aniline radical cations and their further oxidation to nitrobenzene compounds or dimerization to azobenzene compounds. Humic acid (HA) significantly reduced the transformation rates of substituted anilines with Fe(VI) even though considering the effect of oxidant consumption. This suppression effect likely resulted from the reaction between HA and the aniline radical cation, where the aniline radical cation was turned back to parent compound. Meanwhile, it was found that HA also had an impact on the formation kinetics of oxidation products. The effectiveness of Fe(VI) for degradation of substituted anilines in natural water was evaluated, where background matrix constituents could affect both the kinetics of contaminants degradation and products formation, similar to the case of HA. These results have advanced the understanding of Fe(VI) chemistry involved in water and wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Enhanced degradation of OCs was obtained by TAP in the presence of Cl−. • Different reactive species contributed to OCs degradation during Cl−/TAP oxidation. • TOC removal efficiencies were 52.6 %–69.0 % using TAP in the existence of Cl−. • The concentrations of typical CBPs were 17.2 μg/L–86.3 μg/L in Cl−/TAP system. The effect of chloride ion (Cl−) on the degradation of organic contaminants (OCs) by thermally activated peroxymonosulfate (TAP) was assessed in this study. P -aminobenzoic acid (PABA), sulfadiazine (SDZ), bisphenol A (BPA), and chloramphenicol (CAP) were employed as model OCs with different structure. The degradation efficiencies of PABA, SDZ, BPA, and CAP were respectively 76.4 %, 90.8 %, 10.1 %, and 14.5 % by TAP (70 °C) after 60 min treatment, further raised to 97.6 %, 97.4 %, 55.2 %, and 30.5 % in the presence of Cl− (1 mM). When Cl− concentration increased to 10 mM, PABA and SDZ were completely degraded respectively after 7 min and 10 min, 97.1 % of BPA and 59.5 % of CAP were removed within 60 min. In TAP system, PABA and SDZ were primarily degraded by direct peroxymonosulfate (PMS) oxidation, while BPA and CAP were mostly removed by hydroxyl radical and sulfate radical oxidation. In Cl−/TAP mixtures, the degradation of PABA and BPA was mainly attributed to hypochlorous acid oxidation, SDZ was chiefly removed via direct PMS oxidation, and CAP was principally oxidized by radicals. Furthermore, the intermediate products of OCs degradation during Cl−/TAP oxidation were identified, and primary degradation pathways were proposed. The removal efficiencies of total organic carbon were markedly improved from 19.3 % to 25.3 % by TAP to 52.6 %–69.0 % in Cl/TAP system. The concentrations of typical chlorinated by-products after OCs oxidation were 17.2 μg/L–86.3 μg/L in Cl−/TAP system. Considering the complexity of actual wastewater, 51.3 %–100 % removal efficiencies of OCs by TAP oxidation were achieved in Cl−-containing secondary effluent. Understanding the role of Cl− in OCs degradation is essential for the practical application of Cl−/TAP oxidation in advanced wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel PN/Anammox system with low ammonia and no temperature control was developed. • Low sludge is advantageous for the suppression of NOB activity by light. • Stable nitrification was achieved by light irradiation under mainstream conditions. • Ellin6067 of light-resistant AOB bacteria enhances nitrification system performance. • PN/Anammox achieves a total nitrogen removal rate of > 90 % under mainstream conditions. PN/Anammox, as an economical and effective nitrogen removal process, is of great significance for reducing carbon emission in municipal wastewater treatment. However, municipal wastewater has mainstream characterized of low temperature and low NH 4 +-N concentration, and NOB activity is difficult to inhibit, so achieving a stable PN process is the biggest challenge in the application of PN/Anammox to mainstream wastewater. This study developed a method for stable and efficient PN/Anammox based on very low sludge volume (MLVSS = 65 mg/L). Even when the temperature dropped to 15℃ or there was exogenous nitrite-oxidizing bacteria (NOB) interference, the system still had good inhibition of NOB activity. The total stable operation time was 386 days, and the NO 2 –-N accumulation efficiency could reach more than 90 %. Ellin6067 , Nitrosomonas and Candidatus_Brocadia were the dominant functional microorganisms in the system. Nitrospira was the dominant genera of NOB with very low relative abundance (<0.04 %). The mechanism of the long-term stable mainstream PN/Anammox system showed that low sludge content was beneficial to light irradiation on microorganisms in the reactor, while nxrA , the functional gene of NOB, had weak light resistance and oxidation resistance, which makes the system had strong inhibition effect on NOB. The construction of this new system which does not depend on activated sludge volume and complex NOB activity inhibition strategy can better promote the practical application of PN/Anammox under mainstream conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cerium-based MOFs hydrolytic nanozyme benefited methane production by 7.8 − 22.2 %. • Nanozyme facilitated the hydrolysis, acidogenesis, and methanogenesis processes. • This study revealed the adaptive mechanism of microbes to hydrolytic nanozyme. • Nanozyme boosted ATP synthesis by enriching genes for ion pumps and ATP synthase. • This work offers new insight into artificial enzyme application in sludge treatment. Artificial nanozymes have demonstrated potential as natural enzyme substitutes due to their efficient biomacromolecule hydrolysis. However, the metabolic and catalytic mechanisms of nanozyme during the biodegradation of complex organics remain inadequately understood. This study evaluated the effect of the hydrolytic mechanism of cerium-based metal–organic frameworks (Ce-MOFs) hydrolytic nanozyme on shaping microbiome and metabolic functions. Biochemical methane potential test revealed that Ce-MOF-based hydrolytic nanozyme increased methane production by 7.8 − 22.2% as the hydrolytic nanozyme dosage increased from 50 to 150 mg/g VS. The highest methane production observed in 150 mg/g VS dosage of Ce-MOF (Ce-MOF-150) could be attributed to the enhanced sludge hydrolysis, acidogenesis, and methanogenesis processes, proven by the increased relative abundance of dominant acidogens and methanogens. Furthermore, 150 mg/g VS hydrolytic nanozyme bolstered the relative abundance of genes encoding acetyl-CoA carboxylase (accABCD) and involving in glycolysis (hxk and pfkA). These quantities were higher (8.31 − 34.14%) than that without nanozyme addition. The enhanced relative abundance of ackA , pta , cdhCDE , mvhAD , fpoABCDHIJKLMNO , vhoC , rnfABCDEG , mtrABCDEFGH , and hdrABC in the Ce-MOF-150 test indicated that the high proton conductivity of nanozyme facilitated acetoclastic methanogenesis and membrane-bound electron transport system, thereby enhancing methane production. These findings contribute to the expanding understanding of the application of artificial nanozymes as biocatalysts for solid waste resource recovery, providing a promising approach for methane production from sewage sludge. [ABSTRACT FROM AUTHOR]

• Study on comfort and energy savings through human-centric design. • Probing smart textiles' role in heat transfer management. • Examining radiative, conductive responses in thermoregulating systems. • Assessing pros and cons of advanced thermoregulating materials. • Future research scope in polymer-based thermoregulating apparel. This review addresses the burgeoning field of thermoregulating textiles, highlighting their role in enhancing human thermal comfort and reducing building energy consumption. It delves into the development and application of smart textiles, leveraging novel materials and methods to regulate heat transfer between human skin and the environment. The review systematically explores various thermoregulating strategies, including radiative, conductive and responsive mechanisms in both active/passive and bidirectional textile systems. It provides a critical analysis of the strengths and limitations of these smart textiles and identifies crucial challenges in the field. Furthermore, it offers forward-looking insights into future research trajectories in the rapidly evolving domain of advanced thermoregulating clothing. The roadmap for future development in thermoregulating textiles includes enhancing current materials, innovating new solutions and ultimately establishing global standards for widespread, versatile applications across various industries. [ABSTRACT FROM AUTHOR]

[Display omitted] • The typical kinetics and reaction mechanism of fly ash carbonation were described. • Accelerated CO 2 mineralization technology was summarized in terms of reactor design and pretreatment. • The mechanism of different types of chemical additives to accelerate the carbonation of fly ash was summarized. • Carbonation products obtained from different pathways and utilization were analyzed and compared. • Scale-up applications and main challenges of fly ash carbonation technology were summarized and prospected. As global climate issues become increasingly pronounced, human society is confronting unprecedented environmental challenges. The escalating anthropogenic carbon dioxide (CO 2) emissions have intensified the global warming process, resulting in a cascade of environmental degradation issues. CO 2 mineralization stands out as a highly promising approach for carbon capture, utilization, and storage (CCUS) to mitigate global warming. This paper provides a comprehensive review of the current state of accelerated CO 2 mineralization using typical industrial solid waste, "fly ash," as a raw material. The article commences by introducing the physicochemical properties of fly ash, and various typical CO 2 mineralization kinetic models. Subsequently, it provides a comprehensive evaluation of accelerated CO 2 mineralization pathways, encompassing reactor design (reactor types, operational parameter design, etc.), fly ash activation pretreatment (milling, calcination, etc.), and chemical additives (organic amines, amino acid salts, sodium salts, ammonium salts, etc.). A summarization and analysis of the integrated utilization of products obtained through different mineralization pathways are presented. Finally, the paper discusses the scale-up applications and potential challenges faced by reported fly ash carbonation, emphasizing that research on accelerated solid waste carbonation is an inevitable process for the industrial application of this technology. We hope that this review will contribute to advancing the industrialization of CO 2 sequestration through mineralization of solid waste. [ABSTRACT FROM AUTHOR]

[Display omitted] • Peracetic acid and peroxymonosulfate were two peroxides that can be activated by graphite via electron transfer mechanism. • Adjacent transferring and electron shuttling were two different electron transfer routes. • Peracetic acid and peroxymonosulfate were reactive to hydroxyl groups and defective structure, respectively. • Oxidation efficiency of electron transfer pathway has high resilience under complicated water matrices. Electron transfer pathway (ETP) driven by carbon-catalytic peroxides has become appealing strategy for microcontaminants (MCs) removal, whereas the nature of ETP occurring in different peroxides system is ambiguous. This work developed a controllable model for peroxides activation by using graphite (GP) that is characterized as simple configuration and excellent electronic conductivity. Peracetic acid (PAA) and peroxymonosulfate (PMS) could be readily activated by GP with 72.2% and 93.7% removal efficiency of sulfamethoxazole, respectively, but peroxydisulfate (PDS) and hydrogen peroxide (H 2 O 2) showed low reactivity to GP activation. For PAA/GP system, the adjacent transferring type of ETP was the primary oxidation mechanism with formation of metastable surface complexes to extract electrons from MCs; while the electron shuttling was the dominate ETP route in PMS/GP system via conductive GP acting as a bridge, promoting direct electron transport from organics to PMS and accounting for 49% oxidation efficiency at pH 7.0. Hydroxyl groups of GP were proposed to be decisive sites to form PAA-GP* complexes, while sp2-hybridized carbon functioned as the electron shuttler in PMS oxidation. Importantly, ETP process would not be affected by the coexistence of multiple anions and natural organic matter to remove mixed MCs in actual water. Our work dedicates to exploring selection of various peroxides in ETP regimes and presenting the superiority of ETP strategy to treat complicated aquatic environment. [ABSTRACT FROM AUTHOR]

Dewatering and settleability by alkaline hydrolysis and oxidation (e.g. ferrate) has been a key issue in waste activated sludge treatment. This study demonstrated that, the newly prepared newly prepared alkaline ferrate (NPAF), containing Fe(VI) and KOH, could effectively disrupt sludge structure and simultaneously improved the dewaterability. It was determined that, at 500 mg/l of NPAF dosage range, the sludge settleability and dewaterability were improved to 55.1% and 7%, respectively. At low dosage of NPAF (i.e. <150 mg/l), the dissolved organic matter in the medium was increased whereas, in higher concentration (i.e. 200–700 mg/l) free water content of sludge floc was released by degrading polymeric substances and other biological macromolecules. The disintegration and structural damages of sludge floc treated with different NPAF concentration and extent to which complete damage (400 mg/l) were determined by scanning electron microscope. Owing to the presence of alkali-KOH in NPAF, the stability of Fe(VI) was significantly improved by 4–6 times, which may resulted on the excellent performances of NPAF for the degradation of the macromolecules. [ABSTRACT FROM AUTHOR]

[Display omitted] • The addition of In 2 O 3 significantly enhanced the visible light response of Mn(VII) • Intermediate Mn int (Mn(V) and Mn(III)) and •OH were identified as the major oxidants. • Scavenging of photogenerated e- by Mn(VII) contributed to the generation of Mn int. • The reaction of photogenerated h+ with H 2 O contributed to the generation of •OH. • The Vis/In 2 O 3 /Mn(VII) process demonstrated good reusability and robust resistance to water matrices. Activation of permanganate (Mn(VII)) by generating intermediate manganese species (Mn int , i.e., Mn(V) and Mn(III)) has been demonstrated to be an efficient way to enhance the oxidative ability of Mn(VII). In this work, it was found that the addition of indium oxide (In 2 O 3) could significantly enhance the visible light response of Mn(VII) (Vis/In 2 O 3 /Mn(VII)) by selecting flumequine (FLU) as a representative compound. The presence of In 2 O 3 enhanced the degradation of FLU by the Vis/Mn(VII) process with the pseudo-first-order rate constant increasing by around 30 folds. Intermediate Mn int (Mn(V) and Mn(III)) and hydroxyl radicals (•OH) were identified as the major oxidants in the Vis/In 2 O 3 /Mn(VII) process, and •OH outcompeted that of Mn int under alkaline conditions. The scavenge of photogenerated e- by Mn(VII) played a critical role in the generation of Mn int , while the reaction of photogenerated h+ with H 2 O contributed to the generation of •OH. The degradation efficiency of FLU showed a negative relationship with the increase of solution pH, likely due to the electrostatic repulsion between the deprotonated FLU and negatively charged In 2 O 3 surfaces. Increasing Mn(VII) or In 2 O 3 dosages enhanced the degradation of FLU by elevating the concentrations of reactive species. The presence of chloride, bicarbonate, and humic acid slightly inhibited FLU degradation by the Vis/In 2 O 3 /Mn(VII) process, due to their competitive scavenging of reactive species. Totally 14 oxidation products were identified during FLU oxidation by the Vis/In 2 O 3 /Mn(VII) process, and they were likely generated via hydroxylation, defluorination, dealkylation/decarboxylation/deamination, ring-opening, or oxidation pathways. Good stability and reusability of the In 2 O 3 catalyst were obtained. This work proposed a new activation pathway for Mn(VII) and provided a novel approach for the treatment of emerging contaminants in aqueous environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • An updated review of ultrasound-assisted membrane technology is provided. • Theoretical aspects of ultrasound are discussed. • Methods of ultrasound-assisted membrane fouling mitigation are reviewed. • Methods and mechanisms of ultrasound for flux enhancement are addressed. • Potential of UTDR for membrane health monitoring is discussed. In the previous decades, membrane-based separation technologies have found numerous applications in various industries. However, efficient membrane system operation necessitates cost-effective, environmentally friendly means with reduced consumption of chemicals and energy to address restrictions by polarization and membrane fouling. Ultrasound stands out as a distinct approach among current methods for manipulating the physics and chemistry of complex feed fluids in membrane filtration processes, exhibiting satisfactory performance in mass transfer and membrane cleaning. This review provides an overview of the current academic and practical insights, emphasizing physicochemical strategies for diverse ultrasound-assisted membrane systems. The objective is to summarize recent literature related to the use of ultrasound as kernel to improve the separation performance. Based on the technical perspective employing physics and chemistry principles in ultrasound for the liquid transfer, advanced ultrasound-assisted pressure-driven membrane system strategies, compatible ultrasonics applications in membrane bioreactors, and emerging ultrasound-assisted vapor pressure-driven membrane distillation are discussed. The study also covers theories and applications pertaining to acoustic cavitation, cavitation collapse, standing waves, and sonochemical radical effects. Finally, the limitations of current status are elaborated, and the deficiencies of present technologies are reflected upon for the sake of inspiration for novel ultrasound assisted membrane technologies development. [ABSTRACT FROM AUTHOR]

[Display omitted] • E–TiO 2 @rGO with OVs were prepared through crystal defect engineering. • Mixed crystal and OVs enhanced electron-hole pairs separation efficiency. • E–TiO 2 @rGO improved 2,4,6-TCP dichlorination process and degradation efficiency. • The toxicity of 2,4,6-TCP and its intermediates was evaluated via ECOSAR and DFT. Chlorophenolic pollutants pose serious threats to the aquatic ecosystem. Photocatalysis technology has broad prospects for decontamination. In this work, MXene-derived TiO 2 nanocomposites with mixed-crystal characteristics and oxygen vacancies (OVs) (E–TiO 2 @rGO) were successfully synthesized by atmosphere modulation. Compared with commercial TiO 2 and N 2 –TiO 2 @rGO (anatase phase), the rate constants of E–TiO 2 @rGO (0.06874 min−1) over 2,4,6-trichlorophenol (2,4,6-TCP) degradation increased 4 and 1.3 times, respectively. The enhanced photocatalytic performance was attributed to the co-existence of anatase and rutile phases. On the one hand, the mixed-crystal phase narrowed the band gap, broadening the light absorption range. On the other hand, it induced the generation of OVs, which has been demonstrated by DFT calculation. The presence of OVs improved the adsorption and activation of O 2 and H 2 O molecules, beneficial for the formation of active free radicals. In addition, the incorporation of rGO promoted the separation of electron-hole pairs. The Gibbs free energy of 2,4,6-TCP degradation revealed that the OVs and mixed-crystal could reduce the energy barrier of the rate-determining step, thereby boosting the dichlorination efficiency of 2,4,6-TCP. The superoxide free radical (O 2 −) was determined as the dominant active species. Finally, a possible mechanism of 2,4,6-TCP degradation with E–TiO 2 @rGO was clarified clearly. The proposed mixed-crystal defect engineering represents a novel strategy in the design and synthesis of photocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • A trilayer reaction interface of liquid–liquid-solid (L EL -L IM -S) was successfully constructed. • The interfacial microenvironment self-adapts and adjusts the ionic composition according to changes in the pH environment. • Wide pH photocatalytic NO 3 – application was achieved at adaptive L IM -dominated L EL -L IM -S trilayer reaction interface. • This strategy of L EL -L IM -S can be used to tune the activity and selectivity of heterogeneous catalysts. Developing highly efficient photocatalysts with a wide pH application range is the key to achieving widespread practical application of photocatalytic denitrification. However, the current study neglects the limitations of diffusion and mass transfer efficiency in the reaction interfacial microenvironment on high activity and selectivity, resulting in the inability to achieve the ideal results. Herein, the photocatalytic NO 3 – reduction system with a microenvironment-dominated trilayer reaction interface of liquid (external liquid)-liquid (adaptive interfacial microenvironment)-solid (Br-Bi 2 WO 6-x photocatalysts with different charge transfer mechanisms under acid/base conditions and hydrophilic surfaces) (L EL -L IM -S) was successfully constructed. The interfacial microenvironment in the system can self-adapt and adjust its ion composition according to the changes in the pH environment, which facilitates timely supplementation of NO 3 –/HCOO– required for the reaction from external liquid, thus maintaining the relative stability of the microenvironment and achieving an excellent NO 3 – removal rate of over 90 % in a wide pH range from 3 to 9. Meanwhile, the trilayer reaction interface of L EL -L IM -S collectively constitutes a unique carrier shuttle and molecular reaction channel from the catalyst interior to the surface contaminants. Highly selective NO 3 – to NH 3 conversion (NH 3 selectivity of 91.7 %, NH 3 yield of 750 μmol g-1h−1) could be accomplished utilizing this channel. [ABSTRACT FROM AUTHOR]

[Display omitted] • The unique heterostructure of NiOOH/Ni 3 S 2 /NF were synthesized by a two-step methods. • The NiOOH/Ni 3 S 2 /NF exhibits a high formic acid Faraday efficiency of 97.7 %. • The GOR path and the real active sites of NiOOH/Ni 3 S 2 /NF were unveiled. The electrocatalytic glycerol oxidation reaction (GOR) is an efficient way to reduce the overpotential of the anodic reaction of electrocatalytic water splitting with abundant high-value byproducts. However, it has always been difficult to reveal a clear reaction path and real active site during the electrocatalytic glycerol oxidation reaction (GOR) process. In this work, NiOOH/Ni 3 S 2 /NF, a model catalyst was synthesized by the two-step method, and the reaction path of the electrocatalytic oxidation of glycerol on NiOOH/Ni 3 S 2 /NF was clearly unveiled by the in situ infrared and Raman analysis. In addition, the TEM after GOR and in-situ Raman intuitively demonstrated that the NiOOH was the real active site during the GOR process. Consequently, the synthesized NiOOH/Ni 3 S 2 /NF catalyst achieved a current density of 10 mA cm−2 at 1.227 V vs. RHE and obtained a high formic acid Faraday efficiency of 97.7 % at a low potential of 1.4 V vs. RHE. This work demonstrates an effective method for unveiling the GOR mechanism and the other relevant electrocatalytic reaction processes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrogen peroxide and persulfates homogeneously activated by Cu(II) are summarized focusing on the mechanisms. • The introduction of reductants, chelators, and energy improve the catalytic efficiency of Cu(II)-initiated AOPs. • Reactive oxidant species formed are suggested to be identified by direct and multiple strategies. • Perspectives and challenges relating to homogeneously Cu(II)-initiated AOPs are discussed. Cost-effective oxidation is one of the hot topics in the remediation of environmental pollutants in recent years. Copper species have been recognized as efficient activators or catalysts in initiating some advanced oxidation processes (AOPs) to generate strong oxidants. Since many source water/wastewater contain certain amounts of Cu(II), AOPs homogeneously initiated by Cu(II) would have application potential in many cases of polluted water remediation. Although relevant research is increasing, substantial controversies exist in interpreting the mechanism of Cu(II) as an activator or a catalyst. In this review, we presented a relatively comprehensive summary on this topic, comparing the homogeneous hydrogen peroxide-based and persulfates-based AOPs initiated by Cu(II), with an emphasis on the reaction mechanisms. Approaches in literatures to improve the performance of homogeneously Cu(II)-initiated AOPs are illustrated. Furthermore, critical methodologies for the identification of intrinsic reactive species are discussed, including inhibition tests, electron paramagnetic resonance, typical organic compounds degradation, and spectroscopy methods. Finally, concluding remarks and perspectives are made to guide future research. This review is expected to provide a clear interpretation on the homogeneously Cu(II)-initiated AOPs. [ABSTRACT FROM AUTHOR]

Highlights: [•] Mn(II) enhances the oxidation of BA by Fe(III)/H2O2 system. [•] Mn(II) does not change the HO mechanism for the oxidation of BA. [•] The variations of initial k obs and t 1/2 of BA are both nonlinear with the concentration of Mn(II). [•] Mn(II) in Fe(III)/H2O2 system promotes the production of . [ABSTRACT FROM AUTHOR]

[Display omitted] • Electric field weakens interaction energy between GO and ACT in alkaline conditions. • Electric field destroys the hydrogen bond between GO and ACT. • Electric field reduces hydration energy barrier during the escape of ACT from GO. • Electric field makes ACT can desorb from GO surface more easily. • Electric field can change the hydrophobicity on both sides of GO. In the present study, molecular dynamics (MD) simulation was performed to study the effect of electric field on the adsorption characteristics of acetaminophen (APAP) on graphene oxide (GO) under alkaline conditions by calculating and analyzing the structural and energy parameters of a ternary system containing GO, APAP and water molecules. Our simulations result shows that when there is no electric field, the adsorption of APAP on the GO surface is mainly due to the Van de Waals interaction. When the external electric field exists, it can significantly weaken the interaction energy between GO and APAP, destroy the hydrogen bond, and reduce the hydration energy barrier during the escape of APAP from the GO surface, thereby making APAP can desorb from the GO surface more easily. In addition, the applied electric field can change the hydrophobicity on both sides of GO, which means the hydrophobicity and hydrophilicity of both sides of the GO can be switched by changing the direction and strength of the electric field. Our research results are expected to propose a novel GO regeneration method and provide a new perspective to explore the mechanism. [ABSTRACT FROM AUTHOR]

• The slippery coating has physico-chemical synergistic antifouling properties. • The pH response of coatings is explored by a combination of simulation and experimentation. • The adhesion of contaminants to different surfaces is calculated and tested. • The coating provides excellent marine fouling resistance in real sea tests. Bionic superhydrophobic and slippery liquid-infused porous surfaces (SLIPS) have attracted great interest due to their antifouling properties, while the poor stability, complex preparation of porous structures and rapid loss of lubricants, as well as only possessing physical antifouling capability, have hindered their further application. Herein, inspired by the Blue-ringed Octopus' defensive equipment of slippery skin and toxin secretion when faced with predators, an antifouling slippery coating containing repellent is easily prepared. The repellent capsaicin physically connected to the slippery networks can be activated to accelerate release in response to the changes in pH caused by bacterial secretions, and the adhesion resistance of the coating is improved by 99 % compared to aluminum plates, both conclusions confirmed by experimental and computational data. The anti-adhesive properties of the slippery surface, combined with the repellent properties of capsaicin provides the coating with excellent synergistic physico-chemical antifouling performance. This is demonstrated by the fact that the surface of the coating remains clear after contamination with proteins, bacteria and diatoms, as well as after 65 days of marine field testing. Additionally, the slippery surface has self-healing and outstanding anticorrosion ability. Therefore, the eco-friendly coating has promising application prospects in marine field for antifouling purposes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Transformation of phenolic pollutants by PAA was enhanced in the presence of I−, where HOI was the reactive species. • 1O 2 produced from the spontaneous decomposition of PAA was involved in the production of HOI, by oxidizing I−. • Cl− and Br− accelerated the transformation of phenolic pollutants by PAA/I− due to the formation of HOCl and HOBr. • The transformation products would increase the cytotoxicity during the PAA/I−. Peracetic acid (PAA) has been used as a disinfectant/oxidant in wastewater treatment. However, considering that the presence of iodide (I−) would induce the iodinated products in wastewater, the effect of I− on the transformation of phenolic pollutants by PAA was investigated. Herein, the presence of I− enhanced the transformation of phenolic pollutants (bisphenol S (BPS), bisphenol A (BPA), and p -hydroxybenzoic acid (p -HBA)) by PAA. Furthermore, hypoiodous acid (HOI) was reactive species in the PAA/I− system based on radical quenching experiments and electron spin resonance. In this system, PAA, together with 1O 2 that was produced in PAA oxidized I− into HOI. Increasing PAA and I− dose promoted the transformation of phenolic pollutants but the promoting effect was less significant at higher dosage. The increase in H 2 O 2 dose retarded the transformation of phenolic pollutants because of HOI being quenched by H 2 O 2. In a wide range of pH (pH 4.0–10.0), the transformation of BPS, BPA, and p -HBA was pH-dependent and most effective at pH 7.0. The presence of chloride and bromide accelerated the transformation of phenolic pollutants by PAA/I− due to the formation of HOCl and HOBr. Furthermore, HOI substitution was the primary reaction pathway in the transformation of BPS, BPA, and p -HBA by PAA/I−. Finally, the transformation products of phenolic pollutants during the PAA/I− posed higher cytotoxicity compared to the parent pollutants. Overall, our findings improved the understanding of the chemical behavior of PAA in the presence of I− and suggested that the generation of iodinated products raised concerns for water safety. [ABSTRACT FROM AUTHOR]

[Display omitted] • Adding bromide significantly improved the degradation of phenols by chlorine. • The kinetic model accurately simulated the evolution of phenol and oxidant content. • Brominated aromatic DBPs were identified in the chlorine/phenols/bromide systems. • The generated brominated aromatic byproducts could be further converted by chlorine. The seawater intrusion caused by the rising sea level increased the bromide (Br−) levels in the source waters of coastal cities. Adding bromide could significantly improve the degradation of phenol, bisphenol A, and methylparaben by chlorine. Bromide in water was first oxidized to active bromine species, which further reacted with phenols to generate brominated aromatic byproducts. A kinetic model including the reactions of chlorine oxidizing bromide, chlorine with phenol, and active bromine with phenol was established. The reaction rate constants of active bromine with phenols were calculated by fitting the degradation of phenols by chlorine in the presence of different bromide concentrations via the kinetic model. The rate constants of active bromine with phenols (1.5 × 104 to 2.9 × 104 M−1s−1 at pH 7.0) were higher than those of chlorine with phenols (4.0 × 101 to 8.9 × 101 M−1s−1 at pH 7.0), resulting in a bromide enhancement effect. The kinetic model could accurately simulate the evolution of total oxidant concentration with time (R2 > 0.96). Various brominated aromatic byproducts were identified in the chlorine/phenols/bromide systems, and they were first produced and then further degraded by chlorine. The technology of removing bromide and phenolic components from source water should be developed to control the formation of toxic brominated aromatic byproducts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Supramolecular assembly was introduced to enhance surface segregation method. • The supramolecules of Pluronic F118/β-CD were in situ formed in casting solution. • The segregation degree was moderate during membrane preparation process. • The leaching of segregation modifier during application process was reduced. • The resultant ultrafiltration membrane had efficient and durable performance. Surface segregation is a practical, cost-effective technique for preparing and modifying ultrafiltration membranes, yet it often involves in the issue of insufficient stability. Due to the similar nature of surface segregation phenomena during membrane preparation and application, the majority of methods that suppress the surface segregation behavior of modifiers during membrane application for better stability also tend to inhibit that during membrane preparation, consequently compromising the initial membrane performance. In response to this issue, we tentatively introduce supramolecular assembly interactions as a means of achieving equilibrium. Specifically, β-cyclodextrin (β-CD) is employed to manipulate the surface segregation behavior of Pluronic F118, a polyethylene glycol based triblock copolymer. First of all, the hydrophily but water-insolubility of β-CD/Pluronic F118 supramolecules effectively curbs the undersegregation and oversegregation phenomenon during membrane preparation and relieves the leaching issue during application. Moreover, the supramolecular assembly of β-CD acts as a nodal role, enhancing hydrogen bonding, hydrophobic interactions, and molecular chain winding among the membrane bulk polymer (polyether sulfone), Pluronic F118, and β-CD. This effect intensifies with closer molecular chain spacing, further boosting the long-term stability of the segregation modifiers. Unlike common hydrophilic modifiers, β-CD does not need to exert its own antifouling property. Instead, it strengthens the surface enrichment and stability of Pluronic F118 through supramolecular assembly. As a result, significant effects can be achieved with minimal amounts of β-CD added. This advancement paves the way for creating highly efficient, durable, and cost-effective ultrafiltration membranes, with potential significant implications for the field of chemical engineering. [ABSTRACT FROM AUTHOR]

[Display omitted] • NDMA formation can be effectively controlled during the O 3 /Al 2 O 3 process. • NDMA formations are relatively high for O 3 /MnOx/Al 2 O 3 and O 3 /β-FeOOH/Al 2 O 3. • NDMA can be removed by MnOx/Al 2 O 3 and β-FeOOH/Al 2 O 3 catalysts via adsorption. • Bromate control: O 3 /β-FeOOH/Al 2 O 3 > O 3 /MnOx/Al 2 O 3 > O 3 /Al 2 O 3 > ozonation alone. N-nitrosodimethylamine (NDMA) and bromate (BrO 3 -) have been found to be disinfection by-products during ozonation, which need to be solved urgently. In this study, O 3 /Al 2 O 3 , O 3 /MnOx/Al 2 O 3 and O 3 /β-FeOOH/Al 2 O 3 were used to investigate the control of NDMA and BrO 3 - formation during the ozonation of daminozide (DMZ) and Br-. During ozonation alone, NDMA formation decreased from 0.66 to 0.37 μM with increasing ozone dosages (20–100 μM) without tert -butanol (TBA). Greater control efficiency for NDMA formation was observed during the O 3 /Al 2 O 3 process (0.55–0.21 μM), which was attributed to the high hydroxyl radical (•OH) yield, and NDMA formation during the O 3 /MnOx/Al 2 O 3 and O 3 /β-FeOOH/Al 2 O 3 processes changed negligibly (∼0.63 and ∼ 0.65 μM, respectively). The formation of NDMA was affected by different concentrations of Br - , HCO 3 – , tannic acid, and humic acid, which was attributed to the competition for ozone or •OH. During ozonation process, the addition of catalysts could effectively control BrO 3 - formation due to the decomposition of HOBr and the adsorption or reduction of BrO 3 - by catalysts. The control efficiencies of BrO 3 - formation were in the order of O 3 /β-FeOOH/Al 2 O 3 > O 3 /MnOx/Al 2 O 3 > O 3 /Al 2 O 3 > ozonation alone. In a real water sample without Br - , significant control of NDMA was observed in the presence of the catalysts. In a real water sample containing Br-, NDMA formation decreased in the presence and absence of catalysts, and a great control capacity for BrO 3 - formation was exhibited during the O 3 /Al 2 O 3 , O 3 /MnOx/Al 2 O 3 and O 3 /β-FeOOH/Al 2 O 3 processes. Therefore, the addition of catalysts can be utilized to control disinfection by-products during ozonation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Separation mechanisms including adsorption via COF-based membranes are investigated. • The latest synthesis methods and application of COF-based membranes are highlighted. • Pioneering perspectives about existing challenges of COF-based membranes are proposed. • Theoretical guidance for designing high-performance COF-based membranes is presented. With the accelerating steps of urbanization, the freshwater scarcity has been emerging as a serious threat to sustainable economic and social development. Under this circumstance, increasing attention is shifting to alternative water sources, such as wastewater and seawater, to harvest the embedded freshwater for supplement. Membrane technology has been predominately applied in this scenario due to its huge advantages in separation efficiency and economic investment. However, the application, especially with polyamide (PA) composite membranes, is significantly limited by the unsatisfied water flux when reclaiming high-quality freshwater. Recently, covalent organic framework (COF)-based membranes with pure COF or COF-incorporated PA as the selective layer exhibited great promise in alleviating this current dilemma benefiting from its tunable aperture, regular channels and desirable hydrophilicity. Unfortunately, relative research works were mainly focusing on the structure–function relationship between COF and the resultant membrane. In the meantime, the accompanied reviews were derived mainly from summarizing membrane preparation processes and practical applications while paid insufficient attention in the separation mechanisms of the COF-based membranes, which are highly desired for directionally optimizing membrane performance from the theoretical perspective. Herein, the mechanisms involved in water purification through COF-based membranes are systematically investigated, especially in a novel view of adsorption. In addition, the up-to-date synthesis strategies of high-performance COF-based membranes are highlighted. Besides, the latest advances in structure-performance relationship of emerging COF-based membranes for wastewater purification and saltwater desalination are also described in this paper. This review aims to provide theoretical guidance and potential methods for design and preparation of next-generation COF-based membranes with higher-performance for high-quality recovery of freshwater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Stable NO 2 − accumulation (≥89%) is observed during S0-autotrophic denitrification. • S0-PDN is achieved via the inhibition of high FA on NO 2 − reduction. • The maintenance of high pH (8.5–9.5) and FA (36.7–146.9 mg/L) relies on NH 4 +/NH 3. • The drop in functional species and enzyme activity favors the attainment of S0-PDN. • S0-PDN offers an economical NO 2 − supply solution for ANAMMOX without carbon demand. Heterotrophic partial denitrification has been recognized as an efficient nitrite supply technology for anaerobic ammonia oxidation (ANAMMOX), but it cannot eliminate the requirement for organic carbon. In this study, six elemental sulfur-packed bed reactors were operated under high pH and free ammonia (FA) conditions to achieve elemental sulfur autotrophic partial denitrification (S0-PDN) without organic carbon requirement. Long-term performance demonstrated stable NO 2 −-N accumulation (≥89.5%) with optimal pH of 8.5–9.5 and FA concentrations of 36.7–146.9 mg/L in the reactors. The NO 3 −-N conversion was minimally affected with effluent NO 3 −-N concentrations of 35.8–41.4 mg/L and effluent NO 2 −-N concentrations of 52.1–62.1 mg/L. However, achieving S0-PDN at low FA concentrations (≤6.1 mg/L) caused a serious decrease in NO 3 −-N conversion due to high pH (10.0). The success of S0-PDN primarily relied on the inhibition of NO 2 −-N reduction by high FA ensured by NH 4 +/NH 3 buffer system. Metagenomic analysis revealed a decrease in microbial diversity and functional species. The relative abundance of sulfur autotrophic denitrification species in partial denitrification (PDN, 2.0%) was lower compared to complete denitrification (CDN, 3.0%), with Thiobacillus denitrificans and Thiobacillus thioparus being the dominant microorganisms. However, the nitrite reductase genes were enriched in PDN. The mechanism of S0-PDN may be the effect of high FA on the synthesis or activity of nitrite reductase, resulting in a higher activity ratio of nitrate reductase to nitrite reductase in PDN (>5.0) compared to CDN (<4.0). S0-PDN provides an economical NO 2 −-N supply technology for ANAMMOX, potentially promoting significant cost reductions in nitrogen removal for low-carbon wastewater treatment. [ABSTRACT FROM AUTHOR]

• Persulfate-based AOPs have extensive application for contaminated soil remediation. • Experimental parameters and soil properties affect contaminant degradation. • Simple persulfate addition has evolved to couple with various activation methods. • Soil geochemistry, biology, and contaminant dynamics would change after application. • Mathematical models were developed to understand the oxidation process. Sulfate radical-based advanced oxidation processes (AOPs) have been applied in soil remediation to degrade traditional pollutants in situ, such as polychlorinated biphenyls (PCBs), diesel, polycyclic aromatic hydrocarbons (PAHs), and total petroleum hydrocarbons (TPH). Emerging pollutants such as pesticides, pharmaceuticals, and phthalates have gradually entered the treatment list, and removal technology has been optimized from simple persulfate addition to coupling with various activation methods, including iron activation, thermal activation, base activation, and electrical activation. Peroxydisulfate (PDS) is widely used as oxidant in soil remediation due to its low cost and long environmental retention time. Experimental parameters and some soil properties significantly impact the contaminant removal rate. Changes in soil geochemistry, biology, and contaminant dynamics occur after application of this technology. The degradation rate of contaminants in soil is generally characterized by a pseudo-first-order reaction kinetic model. Other mathematical models have also been developed to understand the oxidation process. This review provides an overview of persulfate-based AOPs for organic contaminated soil remediation, especially for the deep understanding of the activation mechanisms and influential factors. [ABSTRACT FROM AUTHOR]

• A Novel 3D Adsorbent of Reduced Graphene Oxide-β-Cyclodextrin Hydrogel (r-GO-CD) was firstly synthesized. • Plausible formation mechanism of r-GO-CD was explained. • r-GO-CD showed excellent adsorptivity and selectivity towards BPA in water. • r-GO-CD displayed a promising environmental application potential. • Adsorption mechanism of r-GO-CD was proposed and verified. A novel three-dimensional (3D) adsorbent of reduced graphene oxide-β-cyclodextrin (r-GO-CD) aerogel was firstly synthesized through a one-step hydrothermal reaction. Various physicochemical characterization results demonstrated that the cross-linking of "soft" β-cyclodextrin among the "hard" graphene oxide nanosheets, simultaneously combining with self-assembly process of aerogel, contributed to the formation of superior structural and stable r-GO-CD aerogel. The adsorption of bisphenol A (BPA) onto r-GO-CD was chemisorption and endothermic, which fitted well with the pseudo-second-order kinetic and Langmuir isotherm. The saturated adsorption capacity of r-GO-CD towards BPA was 346.0 mg g−1 at 298 K, which was ∼11 times to that of conventional activated carbon. The r-GO-CD displayed a promising environmental application potential as revealed from the stable BPA adsorption efficiency in diverse interferences (H+/OH−, NaCl), presence of trace BPA and repeated cycling tests. The long-term dynamic filtration experiment conducted with raw surface water showed that the effective treated volume of r-GO-CD towards BPA (100 μg L−1) was 270 mL which was ∼30 times to that of r-GO due to the excellent selectivity and adsorptivity of β-cyclodextrin for BPA. The distinct adsorption mechanism of r-GO-CD aerogel was demonstrated as synergistic effects of graphene oxide nanosheets and β-cyclodextrin, along with π-π interaction and hydrogen bonding. [ABSTRACT FROM AUTHOR]

• DEET degradation is comparatively studied in Mn(III) oxidation and PMS/Co(II). • Oxidative and non-oxidative mechanisms coexist in the Mn(III) oxidation of DEET. • Compared with PMS/Co(II), Mn(III) attacks preferentially the N-ethyl in DEET degradation. • Mn(III) oxidation is more effective to eliminate the toxicity of DEET than PMS/Co(II). Mn(III) has great potential for the oxidation of organic pollutants. In permanganate/bisulfite system, Mn(III) would form and react with target organics within seconds. Fast reaction makes revealing the reaction mechanisms difficult. In comparison, Fe2+/Mn2+/sulfite system can slowly release Mn(III) and facilitate the investigation of reaction mechanisms. Herein, N,N-diethyl-3-methyl benzoyl amide (DEET) was used as the target pollutant to comparatively study the oxidation selectivity of Mn(III) and peroxymonosulfate (PMS)/Co(II). By analyzing the transformation products (TPs) of DEET and Mn(III) consumption, we found that oxidative mechanism mainly existed in PMS/Co(II) process, whereas oxidative and non-oxidative mechanisms coexisted in Mn(III) oxidation process. The quantitative analysis of TPs illustrated that the peak concentration of dealkylation TP (TP-163) (the integral part of the relative molecular mass) and acetylation TP (TP-205) during Mn(III) oxidation process was 1.3 and 1.7 times higher than that in PMS/Co(II), respectively. Meanwhile, the peak concentrations of mono-hydroxylation TP (TP-207-I) in Mn(III) oxidation was lower than that in PMS/Co(II). Compared with PMS/Co(II), Mn(III) attacked preferentially the N-ethyl group during DEET degradation process. Toxicity assay suggested that Mn(III) oxidation technology was more effective on eliminating the toxicity of DEET than PMS/Co(II). [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • WTRs was employed as potential iron source and catalyst support of CoFe 2 O 4. • CoFe 2 O 4 @WTRs could efficiently activate peroxymonosulfate to eliminate atrazine. • Activation mechanism and degradation pathways were elucidated and proposed. Abstract Drinking water treatment residuals (WTRs), an iron-rich byproduct generated during potable water production, is a potential resource with utilizable value. In this study, with WTRs as potential iron source and catalyst support, a novel CoFe 2 O 4 @WTRs hybrid was fabricated via a modified chemical co-precipitation combined with calcination method and employed as high-efficient peroxymonosulfate (PMS) activator for the degradation of atrazine (ATZ). CoFe 2 O 4 was successfully synthesized and well dispersed onto WTRs. CoFe 2 O 4 @WTRs exhibited superior catalytic reactivity towards PMS and 98.2% of ATZ degradation was achieved with 0.03 g L2−1 CoFe 2 O 4 @WTRs, 0.20 mM PMS, and 10 μM ATZ at initial pH 4.01. The catalytic performance of CoFe 2 O 4 @WTRs was evaluated with respect to various stoichiometric Co/Fe ratio, catalyst dosage, PMS concentration, and initial pH. Sulfate radical (SO 4 −), generated through cobalt-mediated heterogeneous and homogeneous activation reactions, dominated ATZ degradation in the CoFe 2 O 4 @WTRs/PMS system. The underlying activation mechanism was elaborated based on radical species determination and X-ray photoelectron spectroscopy (XPS) observations. The intermediates of ATZ were identified by LC-MS with three main degradation pathways proposed, including dealkylation, dechlorination-hydroxylation, and deamination-hydroxylation. Finally, CoFe 2 O 4 @WTRs showed good application prospect in the remediation of ATZ contaminated real water under acidic condition. [ABSTRACT FROM AUTHOR]

• The classical 1O 2 -generation H 2 O 2 /OCl− system was used as comparison to some non-photochemical systems for the first time. • Dimol emission of singlet oxygen relaxation was used to investigate the 1O 2 role in some non-photochemical systems. • Methanol, acetonitrile and deuteroxide were used to explore the reaction characteristic of 1O 2 in these solvents. • The defects of quenching and EPR experiments for 1O 2 identification were discussed by experimental data. Singlet oxygen (1O 2) is considered as the dominant reactive oxygen species (ROS) responsible for micropollutants degradation in many non-photochemical systems. However, the role of 1O 2 in non-photochemical systems is overrated due to overlooking the fast quenching of 1O 2 in water and the false positive results of electron paramagnetic resonance (EPR) experiments for 1O 2 identification. Herein, we systematically compared the classical 1O 2 -generation H 2 O 2 /OCl− system and some non-photochemical systems in pollutants oxidation, electron paramagnetic resonance (EPR) experiments and dimol emission of singlet oxygen in different solvents for the first time. The results showed that almost all 1O 2 were deactivated by water and hardly consumed by micropollutants in non-photochemical systems considering the high deactivation rate constant of 1O 2 in water. Moreover, the EPR signals of TEMPO free radical detected in non-photochemical systems may not precisely represent the existence of 1O 2. These results indicated that some others ROS rather than 1O 2 , for example, dioxiranes in the ketone-catalysed decomposition of peroxomonosulfate (PMS), were responsible for the degradation of micropollutants in some non-photochemical systems, and further investigation about the real ROS are needed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Soybean biochar (SB) exhibited superior surface-area-normalized catalytic ozonation activity. • SB contained highest pyridine N and carbonyl group content which enhanced ozone activation. • SB contained strongest delocalized electron density and electron donor ability. • These biochars activated ozone to generate •OH, O 2 •− and 1O 2 for atrazine degradation. Selecting the biomass source is critical because different plants or tissues may exhibit varying textures and chemical properties. However, few researchers have compared the catalytic activity of different tissues from the same plant after carbonization. Soybean is widely cultivated worldwide and always suffers from pests and diseases. The inappropriate storage of harvested soybeans leads to mildew and its wastage. Herein, soybean biochar (SB), soybean shell biochar (SBS), and soy straw biochar (SS) catalysts were prepared using waste soybean plant tissues as precursors, which drastically improved the degradation efficiency of atrazine in catalytic ozonation. The specific reaction rate constant normalized by the surface area (k obs / S BET) of SB during catalytic ozonation indicated the catalytic performance of biochar was not affected just by S BET. The characterization results showed that the delocalized π-electrons, nitrogen-, and oxygen-containing functional groups played key roles in catalytic ozonation, and contributions of these active sites to the generation of both radical and nonradical reactive oxygen species (ROS) including hydroxyl radicals (•OH), superoxide radicals (O 2 •−), and singlet oxygen (1O 2) contributed to atrazine degradation. Compared with SBS and SS, SB contained the highest pyridine N content, the highest carbonyl group (–C = O) content, the strongest delocalized electron density, and electron donor ability, which was responsible for its superior catalytic performance. Such active sites on biochar enhanced the ozone adsorption and decomposition, accelerated the electron transfer process to produce more ROS, and achieved efficient pollutant elimination. Overall, guided by the "waste treating waste" concept, this study provided a valuable alternative in the recycling and reuse of agricultural waste soybean plants, proving that the derived biochar could be potentially used as a catalyst for advanced oxidation processes-based applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • ATL degradation was retarded with the increase in wavelengths and solution pH. • IBF and BZF were used to jointly detect the steady-state concentrations of ClO and Cl 2 −. • O 3 was the major contributor to ATL degradation in the pH range of 7.0–9.0. • The increase of pH decreased the contributions of OH and RCS, but enhanced the contribution of O 3. • Increase in pH and wavelength decreased the concentrations of DBPs. Ultraviolet A light-emitting diode (UVA-LED)-activated chlorine effectively degraded micropollutants at different irradiation wavelengths. Quenching experiments indicated that OH, reactive chlorine species (RCS), and O 3 were the main reactive species for degradation of atenolol (ATL). Bezafibrate and ibuprofen, were used for the first time to jointly quantify the concentrations of Cl 2 − and ClO. Notably, O 3 contributed most to the degradation of ATL (38.9%), following by OH (30.2%) and RCS (27.6%) at pH 7.0 by the UVA-LED/chlorine at 385 nm. ATL degradation increased with the decrease of wavelengths, due to the higher quantum yields of chlorine. The k obs of ATL was positively correlated to the quantum yield of chlorine at the UVA wavelength band. Higher light intensity could enhance the photolysis of chlorine, leading to enhanced ATL degradation. The protonated chlorine is more conducive to the degradation of ATL. Specifically, the contributions of OH, O 3 , and RCS to ATL degradation changed from 40.9%, 6.53%, and 41.0% at pH 4.0 to 11.6%, 59.9%, and 26.6% at pH 9.0, respectively. Cl− had no significant influence on ATL degradation, mainly due to the synergistic effect of different reactive species. HCO 3 − and HA inhibited ATL degradation owing to the quenching effect for reactive species and/or UV filtering effect. The primary transformation pathway of ATL included hydroxylation, chlorination, and bond-cleavage pathways based on the structures of the eight identified transformation products. Seven chlorinated disinfection by-products decreased as wavelengths and pH increased. The above results show that UVA-LED/chlorine might be an efficient process for water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Persulfate is synergistically activated by hybrid homogeneous-heterogeneous process. • SO 4 •−, •OH and Fe(IV) made concerted efforts to phenol degradation. • A new formation path of aqueous Fe(IV) in Fe2+/persulfate system was proposed. • The effect of Fe(IV) on phenol degradation was disclosed from a DFT perspective. • Various phenolic compounds were effectively degraded in FeO/persulfate system. This study presents new findings on persulfate (PDS) activation by iron(II) oxide (FeO). PDS was activated through both homogeneous and heterogeneous approaches, while the latter played a dominant role. The species responsible for phenol oxidation were identified as SO 4 −, OH, and high-valent Fe(IV). A new possible formation pathway of aqueous Fe(IV) is proposed, involving electron transfer between SO 4 −/OH and Fe(III)–OH complex. Density functional theory calculations support that Fe(IV) is apt to attack phenol by electrophilic addition on the benzene ring and hydrogen atom abstraction on the phenolic hydroxyl group. Phenol removal was accelerated at a higher catalyst dosage or PDS concentration but inhibited at higher pH. The coexistence of inorganic anions (e.g., PO 4 3−, SO 4 2−, NO 3 −, and Cl−) and fulvic acid have different effects on this system. Phenol degradation mainly occurred through hydroxylation and eventual ring-opening. In addition, the FeO/PDS system has not only achieved a high removal effect on other phenolic compounds but has also exhibited high performance in actual water. Thus, this system is anticipated to be a promising treatment technique for phenolic-polluted water. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The first triplet state of TCBQ preferred to react with H 2 O via 1,4-addition. • 1,4-addition of H 2 O to TCBQ could facilitate the dechlorination with Cl− release. • A similar addition pathway could induce the dechlorination of the monohydroxylated product of TCBQ. Abstract In this work, a systematical investigation on the transformation of tetrachloro- p -benzoquinone (TCBQ) under UV irradiation (at 253.7 nm) in aqueous solution has been conducted through quantum chemical calculations. The UV irradiation at 253.7 nm could induce the excitation of TCBQ to its first excited singlet state, followed by the intersystem crossing to its first triplet state. In aqueous solution, the first triplet state of TCBQ was thermodynamically and kinetically feasible to react with H 2 O via 1,4-addition, where the addition of OH− to the α–β conjugated system was the dominant step. Interestingly, with the addition of hydroxyl to TCBQ, the dechlorination of TCBQ occurred with the formation of the monohydroxylated product of TCBQ (OH-TriCBQ). The UV photolysis pathway of OH-TriCBQ was similar to that of TCBQ, and the 1,4-addition of OH− to the ortho-position of the hydroxyl was the most efficient pathway. The dechlorination by 1,4-addition of OH− was also observed for OH-TriCBQ. With much larger forward energy barriers, the nucleophilic addition of carbonyl by OH− (i.e., 1,2-addition) might be less important for the UV photolysis of TCBQ and OH-TriCBQ. The findings in the present study may help to understand the transformation of TCBQ in aqueous solution. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights: • Efficiency and degradation mechanism of NPX in Cu2+/HA/PMS process were studied. • HA enhanced the degradation of NPX by accelerating the cycle of Cu+/Cu2+. • Cu+ activated PMS to produce radicals. • Both SO 4 − and OH were dominant radicals in Cu2+/HA/PMS process. • NPX degradation pathways in Cu2+/HA/PMS system were proposed. Abstract Peroxymonosulfate (PMS) activated by Cu+ has been regarded as an effective activation method to generate sulfate radical and hydroxyl radical, however, this process is limited for the poor reduction of Cu2+ to Cu+ by PMS. In this study, hydroxylamine (HAm) was introduced to improve the oxidation capacity of Cu2+/PMS process, meanwhile the degradation efficiency of naproxen (NPX) in Cu2+/HAm/PMS system was investigated for the first time. It was found that HAm could accelerate the redox cycle of Cu2+/Cu+, leading to an enhancement on NPX degradation. The NPX degradation efficiency in Cu2+/HAm/PMS system was 10 times and 2 times of that in Cu2+/PMS and HAm/PMS in 5 min at pH 4.0. The analysis of steady-state concentration of Cu species showed that HAm could enhance the transformation of Cu2+ to Cu+, leading to an improvement on NPX degradation in Cu2+/HAm/PMS system. Both sulfate radical and hydroxyl radical were identified as the dominant reactive species by indirect and direct methods, and PMS activation was attributed to the formation of Cu+ proved by neocuproine experiments. Eight degradation products of NPX were identified by LC-MS/MS, and four oxidation pathways were proposed. This study gives a preliminary interpretation on the enhancement of NPX degradation in Cu2+/HAm/PMS system under the acidic condition, and broadens the scope of HAm enhanced Cu-catalyzed PMS system for the treatment of organic contaminants. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • UV/PDS is proposed to be unsuitable for treatment of bromophenols compared to UV/H 2 O 2. • Brominated polymeric products can be formed in UV-based oxidation process. • BrO 3 − evolution in the degradation of 2,4-DBP by UV/PDS exhibited biphasic kinetics. Abstract The sustained massive use of bromophenols in industrial products leads to their especially pernicious in aquatic environments. This study explored the oxidation kinetics of 2,4-bromophenol (2,4-DBP) and formation potential of bromate (BrO 3 −) and brominated polymeric products of concern during water treatment by UV/persulfate (PDS) and UV/hydrogen peroxide (H 2 O 2). 2,4-DBP exhibited appreciable reactivity toward sulfate radical (SO 4 −) and hydroxyl radical (HO). The second-order rate constants of SO 4 − and/or HO with 2,4-DBP at pH 9 were higher than those at pH 5 and 7. It is mainly due to the deprotonation of the hydroxyl group in 2,4-DBP when pH > pKa (pKa = 7.79). The chloride ions (Cl−) significantly inhibited 2,4-DBP degradation in UV/PDS process, which showed little inhibition in the UV/H 2 O 2 process. Carbonate/bicarbonate (CO 3 2−/HCO 3 −) and natural organic matters (NOM) significantly retarded 2,4-DBP degradation in both processes. BrO 3 − formation in UV/PDS process in the presence of 2,4-DBP (as organic carbon model compound) exhibited biphasic kinetics, i.e., BrO 3 − was undetectable in the lag phase and rapid generated in the secondary rapid phase. However, BrO 3 − was not detected throughout UV/H 2 O 2 process. According to the analysis by electrospray ionization-triple quadruple mass spectrometry, tentative oxidation pathway was proposed. The results showed that brominated polymeric products in the reaction of 2,4-DBP with SO 4 − and/or HO were readily produced by electrophilic addition and coupling reactions. Given the enhanced toxicological effects of these BrO 3 − and brominated polymeric products compared with the bromophenols precursors, it is important to better understand their reactivities and fates when UV/PDS or UV/H 2 O 2 is applied for the oxidative treatment of bromophenols-containing waters. [ABSTRACT FROM AUTHOR]