Search

[Display omitted] • S-Mn@GO significantly promotes the pollutants abatement during Fenton treatment. • S-Mn@GO synergistically accelerates the cycling of Fe(III)/Fe(II) through multiple pathways. • Revealing the mechanisms of multiple active sites promoting the Fe(II) regeneration and pollutants degradation. • HO• dominants the pollutant degradation in S-Mn@GO/Fe(II)/H 2 O 2 system. • S-Mn@GO performs excellent stability and good anti-interference. This study develops a novel sulfurized manganese-supported graphene material (S-Mn@GO) designed for promoting Fe(III)/Fe(II) cycling in Fenton treatment. The excellent combination of manganese oxides (MnO x) and graphene oxide (GO), along with subsequent, impart S-Mn@GO with excellent electron transfer capabilities. Selecting Bisphenol A (BPA) as the model compound to evaluate the efficacy of the novel material, the findings indicate that the addition of 0.1 g/L of S-Mn@GO in the Fe(II)/H 2 O 2 system enhanced the removal of BPA from 49.7 % to 98.3 % within 30 min. Results show that the abatement of pollutants in the S-Mn@GO/Fe(II)/H 2 O 2 system was significantly influenced by pH, with the maximum removal efficiency (98.3 %) attained at pH 3.5. And the common coexist substances at environmental concentration levels on pollutant abatement was examined and this system showed excellent tolerance to anions. Quenching experiments and EPR analyses demonstrate that the hydroxyl radicals (HO•) dominates the abatement of BPA and the other reactive species (e.g., FeIVO2+) show negligible contribution. Density Functional Theory (DFT) calculations and other evidences indicate that the rapid cycling of iron species was due to the coupling of GO and manganese/sulfur (Mn/S) species. Moreover, the degradation pathway of BPA was analyzed through DFT calculations and LC-MS detection. Further, cycling experiments and long-term experiments confirm the stability of the material. Herein, using GO-based composite as an accelerator of Fe(III)/Fe(II) cycling provides a new strategy to promote the pollutant degradation in the Fenton process. [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly dispersed N-doped porous carbon spheres were fabricated for activation of persulfate. • The removal efficiency of persulfate and N-MCHS hinges on pH pzc of N-MCHS. • N-doping greatly enhances the removal efficiency of the system. • Persulfate and N-MCHS efficiently degrade phenolics and antibiotics at low dosages. Persulfate (PS) activation by carbon catalyst holds both scientific and practical significance to curb the toxicity effects of organic pollutants in the natural water environment. Here, we investigated a relatively unfamiliar characteristics (i.e., oxidant-catalyst interaction) that influence the removal efficiency in PS activated system, utilizing N-doped mesoporous carbon hollow spheres (N-MCHS; size ∼385 nm) as a catalyst. The selection of this catalyst was motivated by its desired physicochemical characteristics such as high dispersibility, uniformly distributed pores and high specific surface area (1109 m2 g−1) for catalytic application. The removal performance was studied by degrading bisphenol A at very low PS (0.25 mM) and catalyst (10.0 mg L−1) concentrations. Through this study, we established a correlation between the surface charge of N-MCHS and PS interaction on the catalytic performance. Further, electron spin resonance (ESR) and radical scavenger studies were carryout out to prove the nonradical oxidation process. Electrochemical studies provided a strong evidence for PS complexation and electron transfer during oxidative removal of bisphenol A. Additional studies with different phenolics and antibiotics demonstrated that N-doping significantly accelerates the degradation rate and enhances the removal efficiency. The results of present study unveil the potential use of PS+N-MCHS in the degradation of different organic contaminants at low catalyst dosages. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chitosan coating inhibited the leaching of cobalt ions from Co 9 S 8. • Co 9 S 8 /C exhibits efficient catalytic activity over a wide pH range. • Degradation process was contributed by radical and non-radical ROS. • Co 9 S 8 /C-1 exhibits high levels of structural and performance stability. Cobalt (Co) has significant catalytic activity and is used as an activator of peroxymonosulfate (PMS). However, the practical use of cobalt-based catalysts is hindered by metal leaching and cobalt-induced toxicity. To address these issues, we employed a carbon coating strategy that not only addresses these concerns but also enhances catalytic efficiency by providing additional electrons. In this study, chitosan was utilized for the in situ adsorption of anchored cobalt ions, followed by sulfurization and pyrolysis, to form charcoal-loaded Co 9 S 8 composites (Co 9 S 8 /C). Its specific surface area was 79.5 times higher than that of chitosan, and the adsorption rate of PCMX increased by 28.4 %. Within the wide pH range of 3.0 ∼ 11.0, Co 9 S 8 /C /PMS system can degrade more than 98 % of PCMX within 5 min, surpassing the combined degradation efficiencies of the CS-C/PMS and Co 9 S 8 /C S/PMS systems. The chitosan coating facilitates electron transfer between Co 9 S 8 and PMS, enabling the redox cycle between metal and electrode pairs. Furthermore, in addition to the well-known reactive species SO 4 ·− and ·OH, the presence of Co (IV) adsorbed on the surface of Co 9 S 8 /C-1 significantly enhanced PCMX degradation, whereas low-valent sulfur expedited the rate-limiting process of Co3+ reduction to Co2+. The Co 9 S 8 /C/PMS system also demonstrated high efficiency in treating other representative emerging pollutants such as sulfadiazine, phenol, bisphenol A, and sulfonamide. The chitosan-derived carbon coating strategy presented in this study provides a robust theoretical foundation for the practical application of cobalt-based catalysts, offering promising solutions to the urgent environmental challenges. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of a novel nitrogen and oxygen-doped hierarchical porous carbon for wastewater treatment. • The PDA carbon layer provided abundant oxygen sites and altered the type of nitrogen in the material. • Carbonization temperature and etching time had an effect on the structural properties of carbon materials. • The maximum adsorption capacity of MO by UPCH800 (417.34 mg/g) outperformed most reported MOF-derived carbon materials. MOF-derived carbon materials have garnered significant attention in the field of adsorption due to their abundant porosity, excellent stability, and structural diversity. In this study, nitrogen and oxygen-doped hierarchical porous carbon materials were obtained by carbonizing PDA@UiO-66-NH 2 at various temperatures and subsequently etching with hydrofluoric acid for different times. The adsorption capacity of these materials towards bisphenol a (BPA), methyl orange (MO), and methylene blue (MB) was evaluated. The results suggest excessive carbonization temperature and etching time may cause the collapse of the pore structure. In addition, the introduction of a PDA carbon layer can reduce the nitrogen–oxygen ratio and modify the nitrogen species in the materials. Among these materials, UPCH800, which was carbonized at 800 °C followed by etching for 6 h, exhibits the best adsorption performance towards BPA and MO, with a maximum adsorbed amount of 350.51 and 417.34 mg/g respectively. For MB, the maximum adsorption amount is 227.53 mg/g. All adsorptions reach equilibrium within 1 h. Thermodynamic studies reveal that the adsorption of MO by UPCH800 is an entropy-driven adsorption process, while the adsorption of BPA and MB is an enthalpy-driven exothermic process. Based on experimental and characterization results, the primary adsorption mechanisms involve π-π interactions, n-π interactions, pore-filling, and hydrogen bonding between the pollutants and the material. Moreover, UPCH800 exhibits high removal efficiency after 5 adsorption cycles, making it a promising material for the adsorption of BPA and MO. [ABSTRACT FROM AUTHOR]

[Display omitted] • Membrane separation and molecular imprinting were combined to identify bisphenol A. • Dopamine self-aggregation simplifies the imprinting process. • The molecularly imprinted membranes has good antibacterial and hydrophilicity. • The experiment process was mild, green and environmentally friendly. Bisphenol A (BPA) has been widely detected in environmental and human products and has significant health and environmental impacts. Consequently, an innovative molecularly imprinted membrane was fabricated for the selective adsorption of BPA within water environment. Tannic acid (TA), abundant in plants, was employed to effectuate the reduction of AgNO 3 in an environmentally friendly, and gentle manner, imbuing the membrane with antibacterial properties. A functional hydrophilic layer was created utilizing TA and polyimide (PEI), and mild and efficient imprinting was accomplished through dopamine (DA) self-polymerization. Compared with the blank membrane, the contact angle of the molecularly imprinted membranes (PVDF@Ag@P@MIMs) was reduced to 67.62°, and the optimal adsorption capacity was 33.41 mg g−1. The imprinting factor of the PVDF@Ag@P@MIMs membrane was 2.90, indicating that the membrane could effectively separate BPA. After 6 cycles of utilization, the adsorption loss was only 4.55 %. In addition, the synthesis of PVDF@Ag@P@MIMs is simple and free of pollutants. The experimental results and green synthesis process of the molecularly imprinted membranes indicate that these materials have potential applications in environmental protection, selective separation, chemical industry, and other fields. [ABSTRACT FROM AUTHOR]

• PF enhanced the BPA removal by the MnO X filter media. • Ammonia/manganese promoted the BPA removal. • PF improved the stability of removing BPA for filter media. • The active species included ·OH, 1 O2, and high-valent Fe and Mn. Active manganese oxide (MnO x) filter media can remove NH 4 + and Mn2+ with high efficiency, but the removal of Bisphenol A (BPA) in water has the problem of poor stability, and the interaction between BPA and other inorganic pollutants in water is not clear. In order to improve the ability of continuous removal of BPA, this study used potassium ferrate (PF) to strengthen MnO x filter media to remove BPA from water, and investigated the effects of NH 4 + and Mn2+ on the removal of BPA. The results showed that the removal efficiency of BPA increased from 73 % to 100 % by adding 0.1 mol/L PF, and the removal efficiency increased with the increase of PF concentration. A certain concentration of NH 4 + and Mn2+ increased the removal efficiency of BPA by reacting with high-valent Fe to produce more active substances. The continuous removal of bisphenol A showed that the MnO x filter media had good stability, but the removal efficiency was only 48 % after 11 consecutive BPA removal tests, and the removal efficiency could be maintained above 70 % after adding PF. Combined with the results of free radical quenching, electron paramagnetic resonance (EPR) and methylphenyl sulfoxide (PMSO) experiments, it was confirmed that the active substances in the system included ·OH, 1O 2 , and high-valent Fe and Mn, but the main contribution to the BPA removal was Mn(Ⅲ). The results of X-ray photoelectron spectroscopy (XPS) also demonstrated that the addition of PF generated new active substances on the surface of the filter media, which increased the removal rate of BPA. [ABSTRACT FROM AUTHOR]

[Display omitted] • PMS and PAA can be directly introduced in high-salinity water for organic removal. • Both systems tend to degrade electron-rich phenolics under investigations. • Both systems present certain resistance towards water interferences. Phenolic pollutants are highly toxic and can affect the growth and reproduction of aquatic organisms, as well as contaminate drinking water resources, posing a significant threat to both ecological and human health. However, conventional biological treatment processes are constrained in treating high salinity organic wastewaters due to the potentially lethal effects of high concentrations of dissolved salts on microorganisms. While advanced oxidation processes have shown promise in removing phenolic contaminants from high-saline wastewater, their widespread application is always limited by the high costs associated with energy and chemical usage. In this study, we explored the potential application of directly introducing peroxymonosulfate (PMS) and peracetic acid (PAA) to high-salinity water for the removal of nine phenolic contaminants. By establishing a correlation between the degradation rate constants in the PMS/Cl– (k PMS) and PAA/Cl– (k PAA) systems and various molecule descriptors, two multiple linear regression models were developed to predict the degradation rate constants under investigation. Additionally, we selected bisphenol A (BPA) as the target contaminant and investigated the impact of common ions found in natural water, such as HCO 3 –, NO 3 –, and humic acid, on the removal of BPA using two systems. Finally, we conducted experiments using tap water and sewage water to demonstrate the practical application and performance of the two systems. These experiments aimed to provide valuable insights into the influence of background chloride on PMS and PAA activation, as well as the potential of direct PMS/PAA introduction for eliminating phenolic micropollutants from high-saline wastewaters. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cellulose nanocrystals/polyacrylic acid hydrogel derived Fe/N co-doped carbon was prepared. • As-prepared FeN@CP 800 exhibited prominent adsorption capacity for BPA. • Fe 4 N component showed high binding energy with BPA by DFT calculations. • BPA adsorption was accomplished by multiplexing mechanisms. Conventional carbon-based adsorbents encounter insufficient active sites, low adsorption efficiency and poor anti-interference ability for bisphenol A (BPA) removal. Herein, we developed a cellulose nanocrystal/polyacrylic acid hydrogel derived strategy for the preparation of a novel iron/nitrogen co-doped carbon (FeN@CP 800) via simple immersion of iron (III) acetylacetonate and melamine in hydrogel precursors and further carbonization at 800 °C. The precursor scaffold interacted with active species source by swelling behavior to form hydrogen bonds and Fe coordination, thereby facilitating subsequent growth of multiple active conformations without aggregation. The hierarchical porous surface morphology, abundant N doping, multi-active site structure and large specific surface area significantly improved the accessible BPA adsorption of FeN@CP 800. The maximum adsorption capacity calculated by Langmuir model was 309.17 mg·g−1, 4.5 times higher than that of bare CP. Benefited from pore filling, hydrogen bonds, π-π stacking and hydrophobic interactions, the excellent adsorption performance of FeN@CP 800 was retained under varied coexisting ions species, ionic strength and solution pH with 84 % capacity retention after 5 cycles. DFT calculations disclosed the Fe 4 N component was the predominant active sites to improve the adsorption and interfacial transfer process. Thus, these findings provide a new strategy to design high-performance adsorbent for phenolic pollutants removal in water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metal-free nitrogen-doped hollow carbon spheres (DNC-X) were successfully synthesized. • The DNC-9/PMS system relies mainly on the nonradical pathway for efficient BPA degradation. • The catalytic activity can be recovered by a simple thermal regeneration treatment. • A packed column was constructed based on the DNC-9/PMS system. Peroxymonosulfate (PMS) activation methods conventionally face challenges such as high energy consumption and the risk of metal leaching, limiting their practical application. Metal-free catalysts often face the problem of low catalytic activity. This study designed an in-situ nitrogen-doped hollow carbon catalyst (DNC-9), which offers balances efficient catalytic performance and metal-free catalysis. The results indicate that the DNC-9/PMS system effectively degrades bisphenol A, achieving complete degradation over a broad pH range (3.0–9.0). Through structure modification, the degradation efficiency of bisphenol A compared with SiO 2 @DNC-9/PMS system was improved by around 6 times and the degradation kinetic rate can reach 0.346 min−1. DNC-9 can activate PMS, resulting in a higher concentration of singlet oxygen without the generation of free radicals. Graphitic nitrogen in DNC-9 plays a crucial role in this activation, offering adsorption sites that facilitate decomposition of PMS and generating 1O 2. In addition, graphitic nitrogen forms a transient active intermediate, DNC-9-PMS*, enhancing bisphenol A degradation. The catalyst recovers its high activity to complete bisphenol A removal with 15 min after thermal regeneration in cyclic experiments, demonstrating its potential as a practical solution for the efficient degradation of emerging contaminants. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pre-coagulation reduced NOM attachment to electrified membrane surfaces. • BPA removal by electrified membranes was improved by Pre-coagulation. • Pre-coagulation decreased surface charge of NOM and formed positive micro flocs. • Larger flocs with a branched structure prevent the formation of internal fouling. • Excessive content of cationic polyacrylamide caused irreversible internal fouling. Membrane fouling is one of the issues that hinder the widespread application of electrified membranes. This study focuses on mitigating membrane fouling caused by natural organic matter (NOM) through pre-coagulation techniques. The effectiveness of pre-coagulation was evaluated based on the flux and removal efficiency of electrified membranes. Pre-coagulation can remove a portion of NOM and reduce the negative surface charge of residual NOM, thereby reducing the attachment of NOM to the surface of electrified membranes. As a result, pre-coagulation effectively increased the flux of electrified membranes for treating water samples containing NOM. Additionally, pre-coagulation alleviated the decrease in surface current density of electrified membranes caused by NOM pollution, leading to improved bisphenol A (BPA) removal performance. The effectiveness of pre-coagulation in enhancing membrane performance depends on the choice of coagulant. Compared to polyferric chloride (PFC), PFC-cationic polyacrylamide composite coagulants (PFC-CPAM) facilitated the aggregation of NOM into larger flocs with a branched structure, demonstrating a stronger capability to mitigate membrane fouling. However, it should be noted that the presence of CPAM may result in irreversible internal fouling due to the polarization effect induced by the electric field. Moreover, when the weight ratio of PFC to CPAM was 1:1, the flocs became overly dense, resulting in reduced flux. This study provides valuable insights for the application of pre-coagulation techniques in mitigating fouling issues in electrified membranes. [ABSTRACT FROM AUTHOR]

[Display omitted] • A polyethersulfone/sulfonated polysulfone loose NF membrane was fabricated. • The membrane exhibited high flux and enhanced selectivity of PPCPs/minerals. • The removal of ionic PPCPs is mainly dominated by charge exclusion and adsorption. • Non-ionizable PPCPs are removed by adsorption and size exclusion. Nanofiltration (NF) membranes have a high removal rate for pharmaceutical and personal care products (PPCPs) in drinking water, but they also reject critical minerals (e.g., calcium and magnesium) that are beneficial to health. Herein, polyethersulfone (PES)/sulfonated polysulfone (SPSf) loose NF membranes were fabricated using non-solvent induced phase separation (NIPS) to enable efficient rejection of PPCPs while preserving high mineral permeability. The resultant loose NF membrane showed increased negative charge owing to the -SO 3 - groups of SPSf. It also exhibited a high water permeance of ∼20.8 L m-2 h−1 bar−1 characterized by high PPCPs/minerals selectivity (i.e. , rejection of PPCPs > 90 % and rejection of Mg2+ < 5 %). The filtration performance of resultant membrane indicated that the ionic PPCPs (e.g., Indomethacin, Diclofenac Sodium, Levofloxacin, Norfloxacin) were removed by the electrostatic repulsion and adsorption, while the removal of non-ionic PPCPs (e.g., Bisphenol A, Carbamazepine) was primarily dominated by the synergy of adsorption and size exclusion. Therefore, the superior removal rate of hydrophilic PPCPs was due to enhanced PPCP-membrane adsorptive interaction. This study provides a profound understanding of the selective separation mechanism of loose NF membranes for micropollutants and minerals. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bimetal (Cu/Mo) participation shortened the band gap of g-C 3 N 4. • Cu/Mo@CN significantly enhanced BPA oxidation compared to g-C 3 N 4. • Photogenerated electron and transition metal redox played a crucial role in PS activation. • Possible pathways for the transformation of BPA were proposed by DFT. Degradation of endocrine disrupting compounds by optimizing advanced oxidation processes is highly feasible, but remains a daunting challenge. In this work, a novel copper and molybdenum co-doped g -C 3 N 4 (Cu/Mo@CN) were successfully synthesized via a simple dip-calcination approach, of which highly dispersed Cu and Mo atom sites were doped in the ring of g -C 3 N 4. The Cu/Mo@CN catalysts were characterized by XRD, SEM, TEM, XPS, UV–vis DRS analyses, etc. The optimized system of Cu 1 /Mo 3 @CN catalyst in the visible light-persulfate oxidation (Vis + PS + Cu 1 /Mo 3 @CN system) had high photocatalytic activity to remove 97.2 % of bisphenol A (BPA, 5 mg/L) within 60 min. Compared to pure g -C 3 N 4 , Cu/Mo@CN has better visible-light (Vis) response function and narrower band gap (2.58 eV), which are easier to get excited by Vis illuminate. The results showed that reactive oxygen species of SO 4 • −, •OH and •O 2 − could be stably produced to contribute to the BPA degradation in Vis + PS + Cu/Mo@CN systems. Meanwhile, the Cu and Mo elements co-doped in g -C 3 N 4 can also effectively activate PS to promote the production of reactive oxygen substances. In addition, the continuous production of photoelectrons enhanced the cycling of Cu2+/Mo6+ and Cu+/Mo4+, which could be further improved the removal efficiency of Vis + PS + Cu/Mo@CN towards BPA. The degradation mechanism of BPA were proposed according to the identification of intermediate products and DFT calculation. Overall, this study provides a viable pathway for BPA abatement in actual wastewater treatment applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu-doped MOFs create oxygen-rich vacancy LaFeO 3 via Prussian blue MOFs. • The catalyst exhibits exceptional pH tolerance, breaking down various pollutants. • It effectively removes total organic carbon in both Bisphenol A (BPA) and tetracycline. • Singlet oxygen and superoxide radicals drive BPA degradation. • Boosting catalyst-peroxymonosulfate interaction using Cu doping strategy. This research focused on creating oxygen vacancy-enriched copper-doped LaFeO 3 perovskite using a Prussian blue MOF template. This new material, LFO-Cu, showed outstanding Bisphenol A (BPA) degradation with 98 % efficiency in just 30 min, ten times faster than pure LaFeO 3 (LFO). Moreover, the LFO-Cu/peroxymonosulfate (PMS) system worked effectively at pH levels from 4 to 10, breaking down various pollutants (TC, PhOH, MV, MB), and removing 85 % TOC in BPA and 50 % in TC. Density Functional Theory (DFT) calculations revealed that copper strengthened the catalyst-PMS interaction, leading to the generation of highly reactive oxygen species (ROS), primarily singlet oxygen (1O 2) and superoxide radicals (O 2 –·). A degradation pathway was proposed, showing less toxic intermediates than BPA. In summary, copper-doped oxygen-rich vacancy MOFs-derived perovskite has significant potential for improving refractory organic mineralization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Core-shell structures of Fe@Fe 2 O 3 were generated in-situ on etched carbon felt. • Fe@Fe 2 O 3 /ECF was used for in-situ electro-generation and activation of H 2 O 2. • Fe0 promoted the conversion of Fe3+ to Fe2+. • Fe@Fe 2 O 3 /ECF demonstrated a wide pH application range and excellent stability. The advanced oxidation processes based on the electro-Fenton reactions show great potentials as a wastewater treatment approach for removing emerging contaminants. In the electro-Fenton system, some factors still exist affecting the treatment efficiency, e.g., the formation of iron sludge, a narrow pH working range, and slow conversion rates between Fe2+ and Fe3+. In this research, a novel heterogeneous flow-through electro-Fenton system was constructed, and carbon felt was used as the template material for the preparation of an etched carbon felt cathode loaded with zero-valent iron and iron oxide (Fe@Fe 2 O 3 /ECF) for the degradation of bisphenol A, which addressed the aforementioned issues. The Fe@Fe 2 O 3 /ECF electrode showed excellent performance across a pH range between 3 and 11, with exceptional stability and resistance to other substances in water. For the three pollutants, bisphenol A, tetracycline and ciprofloxacin, the highest degradation efficiency can reach 99.3 %. Compared to traditional electro-Fenton systems, the novel process exhibited superior performances due to synergistic effects from feasible flow design, enhanced electrochemical reactivity and greater exposure of active sites. Through electron spin resonance and free-radical quenching experiments, it was determined that the primary species participating in the heterogeneous electro-Fenton process were the hydroxyl radical and superoxide anion. Specifically, the hydroxyl radical was identified as playing a pivotal role in the degradation of bisphenol A. After a continuous operation of 240 min, the electrode showed low metal ion leaching rate and good stability, with the concentrations of leached Fe and Co ions to be only 17 and 7 μg/L, respectively. Meanwhile, the removal efficiency was only decreased by 5.7 % during the process. Through density functional theory calculation and intermediate product analysis, three potential degradation pathways were proposed, with the cleavage of carbon bonds serving as the main degradation approach. The toxicity analysis demonstrated that the intermediates were generally less toxic than BPA during treatments. This research provides a fresh means for promoting a valence state cycling of ferric species in electro-Fenton system, which has potential applications in wastewater treatment containing emerging contaminants. [ABSTRACT FROM AUTHOR]

• A photo-enzyme coupling catalysis system with an electron transfer pathway was constructed. • The photo-enzyme coupling catalysis has high HRP loading and improved activity. • The HRP/Ppy/CN showed excellent degradation performance for BPA. • The HRP/Ppy/CN system provides a new idea for the development of an efficient photo-enzyme coupled catalytic system. How to enhance the efficiency of electron transfer between the photocatalytic system and the enzymatic catalytic system is the key to constructing novel and efficient photo-enzyme coupling system. Hence, polypyrrole (Ppy) with high adsorbability was employed as a bridge to establish an electron transfer pathway between the photocatalytic system and the enzymatic catalytic system in this work, enhancing both the immobilized amount of the biocatalyst and the efficiency of electron transfer and catalytic activity in the photo-enzyme coupling system. After immobilization optimization, the unit loading of horseradish peroxidase (HRP) can reach 831.00 mg/g, and the immobilized HRP has strong pH stability, storage stability and cycling stability. Moreover, the conversion efficiency (K cat /K m) of immobilized HRP was 0.4800 min−1 mM−1, higher than that of free HRP (0.1560 min−1 mM−1). Moreover, the successful construction of the photo-enzyme coupling system was confirmed by a series of physical characterization, such as FT-IR, XRD, TGA and XPS. In the degradation experiment of bisphenol A (BPA), the degradation rate of BPA by HRP/Ppy/CN photo-enzyme coupling system can reach 86.03 % within 60 min and rate constant is 0.0329 min−1, which is 1.91 times and 3.19 times that of pure g-C 3 N 4 , respectively. This work provides a new idea for the development of an efficient photo-enzyme coupled catalytic system and the effective removal of phenols in water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn-enriched roots of P. Stratiotes can be used to prepare multi-metal catalysts. • Mn(IV) accounts for 37% of Mn species in MF400 but is not detected in MF400-N. • Fe and Mn are the key factors affecting the catalytic performance. • Synergistic effect of ROS and surface reactive Mn(IV) leads to BPA degradation. • The catalyst exhibits excellent activation ability over a wide range of pH. Aquatic plants used for phyto-extracting toxic metals from water are often enriched in certain metals and recycling these metal-enriched plants will achieve the sustainable application of phytoremediation/phytoextraction technology. The present study systematically explores the potential recycling of Mn-enriched-roots of P. Stratiotes used in the treatment of electrolytic manganese residue leachates as catalysts for activating peroxymonosulfate [1] to degrade organics in water. The effects of heat treatment temperature and atmosphere on the catalyst activity were first investigated and the results indicate that catalyst prepared in air at 400 °C contains active Mn(IV) while Mn(IV) was not detected in the catalyst prepared in N 2 at the same temperature, and thereby catalyst obtained in air under 400 °C (MF400) performs better catalytic activity in degrading bisphenol A (BPA). The removal of BPA was found to reach 99.9 % in the MF400/PMS system at 120 min. The BPA degradation pathways were inferred by density flooding calculations (DFT) and then confirmed by liquid chromatography-mass spectrometry coupled detection, indicating that the radical pathway depending on·OH, SO 4 − and·O 2 – is the mechanism for BPA degradation in the MF400/PMS system. The ECOSAR assessment reveals that most BPA degradation intermediates are less toxic than their parent molecule. This work provides a simple and effective way for recycling Mn/Fe enriched aquatic plants used in phytoextraction process. [ABSTRACT FROM AUTHOR]

[Display omitted] • An electro-Fenton coupled membrane filtration (EF-MF) device is used to remove bisphenol A. • Both electro-Fenton and membrane filtering processes played crucial roles in the removal of bisphenol A. • A porous Fe 3 O 4 /FeO/Fe@C catalyst was creatively used in the electro-Fenton process. • The catalyst can effectively accelerate the conversion between ZVI, Fe(Ⅱ) and Fe(Ⅲ). • The catalyst has good stability, and can be easily recovered by magnetism separation. An electro-Fenton coupled membrane filtration system (abbreviated as EF-MF system) was constructed for the efficient removal of bisphenol A (abbreviated as BPA, a kind of pharmaceuticals and personal care products, abbreviated as PPCPs). In the EF-MF system, a porous Fe 3 O 4 /FeO/Fe@C catalyst was synthesized and applied to enhance the electro-Fenton reaction, and polyvinylidene fluoride/carbon fiber cloth composite cathode membrane was used as both cathode electrode and membrane. Characterization results indicated the porous Fe 3 O 4 /FeO/Fe@C catalyst exhibited micron-level rod morphology and was in an encapsulated structure with Fe 3 O 4 /FeO/Fe composite nanoparticles covered by porous graphitic carbon. Degradation experiments indicated the EF-MF system exhibited great removal efficiency (approximately 96.97%) towards BPA within 70 min in the conditions of catalyst dosing at 0.500 g·L−1, the value of pH at 3 and the current density at 0.67 mA cm−2. Quenching experiments verified both OH radical and O2− radical played significant roles in the decomposition of BPA. The mass formation of reactive oxygen radicals was mostly owing to the easy access of H 2 O 2 to the activated sites of the porous Fe 3 O 4 /FeO/Fe@C catalyst through the porous structure and the rapid cycle conversion between zero-valent iron (ZVI), Fe(Ⅱ) and Fe(Ⅲ). Based on the results of intermediates identification, three possible decomposition pathways were presented. Toxicity analysis exhibited most of the intermediates were in less toxicity than BPA. Moreover, the EF-MF system exhibited good stability after four-cyclic utilization. This work provides an efficient and energy-saving strategy for the removal of PPCPs. [ABSTRACT FROM AUTHOR]

• Preparation of molecularly imprinted MOF/PAN hybrid nanofibrous membranes. • Selective and efficient removal of BPA in water. • Detailed adsorption mechanism analysis of molecularly imprinted membranes towards BPA. • Efficient cycling reusability and sustained removal performance on BPA. • Excellent antibacterial fouling property against the Gram-negative and Gram-positive bacteria. Organic pollutants and microorganisms have become the main challenge in sewage treatment for decades. This mainly results from rapidly developing industry and urbanisation. However, simultaneous clearance of the organic pollutants and microorganisms in water still remains challenging in wastewater treatment. To address this problem, a novel molecularly imprinted metal–organic framework (MOF)/polyacrylonitrile (PAN) hybrid nanofibrous membrane (MOF/PAN-MIM) was prepared for selectively adsorbing bisphenol A (BPA) and inhibiting bacterial fouling in water treatment. Based on the experimental results, the MOF/PAN-MIM showed higher affinity towards BPA as compared to any other organic pollutants and a selective adsorption order of BPA > bisphenol F (BPF) > bisphenol S (BPS) > phenol > nitrophenol > resorcinol with adsorption performance 56.63 mg·g−1. The kinetics and isotherm models of the adsorption of MOF/PAN-MIM towards BPA are best fitted to a pseudo-second-order mode and a Langmuir isotherm. The cyclic reusability of the membranes was demonstrated by the regeneration experiments, with a removal efficiency of 77.73% towards BPA and a negligible Cu ion leakage of 0.64% after six adsorption–desorption cycles. Additionally, the inhibition rate against E. coli and S. aureus was measured to be greater than 90% via the antibacterial assay. The above results indicated that the as-prepared MOF/PAN hybrid nanofibrous membrane has efficient selectivity, sustained cyclic adsorption ability, and antibacterial fouling effect, which can be used as a potential multi-functional filtration membrane in real wastewater treatment. [ABSTRACT FROM AUTHOR]

• The FeOCl/PMS/Vis system could efficiently remove and mineralize aquatic organic pollutants. • It was significantly enhancing the activation and utilization efficiency of PMS. • Operation across a broad range of environmental conditions. • The synergistic mechanism between photocatalysis and PMS activation in FeOCl/PMS/Vis system was revealed. Inspired by the photosensitivity and self-heal properties of iron oxychloride (FeOCl), we used photocatalysis coupling peroxymonosulfate (PMS) activation for effective aquatic decontamination in a cost-efficient and environmentally friendly method. Synthesized FeOCl was appointed to activate PMS to degrade bisphenol A (BPA, 2,2-bis(4-hydroxydiphenyl) propane) persistently under visible light. The best performance of FeOCl/PMS/Vis system was ∼100% BPA degradation efficiency which achieved in 20 min. The BPA removal efficiency had a positive correlation with the dosages of FeOCl and PMS, but negatively related to BPA concentration. The FeOCl/PMS/Vis system also presented impressive degradation performance at a wide pH range (pH = 3–11) and showed well excellent stability and reusability. The addition of either bicarbonate or chloride had impressive promotion effect on BPA removal. The reaction mechanism of FeOCl/PMS/Vis system was studied deeply. PMS was activated to generate active radicals (SO 4 − and HO) by Fe(II) of FeOCl for BPA degradation. Then the as-formed Fe(III) was reduced to Fe(II) via trapping photoexcited electrons in conduction band (CB) of FeOCl, which effectively inhibited the recombination of photo-generate charges and the pollutants oxidation would recur via facilitating the Fe(II)/Fe(III) redox recycle. Thus, the activation and utilization efficiency of PMS was effectively improved. This work indicated the FeOCl/PMS/Vis system was a promising application in wastewater treatment. [ABSTRACT FROM AUTHOR]

• The egg-box model was used to explain the flux decline caused by organic foulants. • Fe(II)/PMS was innovatively applied as pretreatment for nanofiltration. • Fe(II)/PMS combined process had greater efficiency in water purification. • Fe(II)/PMS had better performance on fouling alleviation than coagulation. • The unexpected flux deterioration resulted from enhanced gypsum scaling. As a practical advanced oxidation process with high-efficiency, ferrous-activated peroxymonosulfate (PMS) technology has been extensively investigated and employed for the degradation of organic substances in water treatment process. However, to our best of knowledge, few studies in applying ferrous-activated PMS as the pretreatment for nanofiltration process have been conducted and the mechanisms of membrane fouling alleviation due to ferrous-activated PMS was still unclear. Consequently, ferrous-activated PMS approach was innovatively adopted as pretreatment for nanofiltration in present study, compared with the conventional pretreatment process (coagulation). The results indicated that both strategies could significantly mitigate organic fouling at membrane surface, but the gypsum scaling was enhanced when Fe(II)/PMS was adopted prior to nanofiltration process at the dose of 80/80 μM, because of the assistance of ferric ions and sulfate anions. ATR-FTIR spectra indicated that the greater alleviation of flux decline caused by Fe(II)/PMS oxidation was attributed to the less accumulation of organic substances on membrane surface, relative to the conventional Fe(III) coagulation. Furthermore, Xtended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory was utilized to explain the greater interfacial free energy of adhesion (equal to decreased repulsion or increased attraction) between foulants and nanofiltration membranes in ferrous-activated PMS strategies joined nanofiltration process. Interestingly, Fe(II)/PMS oxidation could efficiently improve the quality of effluent in nanofiltration process, and three-dimension excitation emission matrix fluorescence spectroscopy (3D-EEM) spectra demonstrated that Fe(II)/PMS conferred higher removals of organic substances. The removal efficiency of Bisphenol A in Fe(II)/PMS assisted nanofiltration process varied from 53% to 78%, while only 5–12% Bisphenol A was removed in Fe(III) coagulation joined system. Besides, the potential mechanisms of flux decline caused by individual and combined organic substances were also investigated. Therefore, the findings in present study would contribute to the deep understanding of membrane fouling mechanism and promote the practical application of nanofiltration technologies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Diatomic Fe-Co catalysts activate peroxydisulfate to abate bisphenol A. • FeCo-N-C exhibits superior catalytic performance than Fe/Co single-atom catalysts. • Synergy between Fe/Co sites was studied from the whole PDS activation process. • FeCo-N-C/PDS performs efficient pollutants degradation in complex water matrices. The application of catalysts with highly available active sites, such as single-atom catalysts (SACs), is a growing trend in peroxysulfate activation for organic contaminant degradation. However, the single functional active site of SACs limits its performance in such reactions involving multiple steps or reactants. For this issue, a Fe-Co diatomic catalyst (FeCo-N-C) with multi-functional active sites is synthesized to abate bisphenol A (BPA) using peroxydisulfate (PDS) as an oxidant. X-ray Absorption Fine Structure (XAFS) measurement confirms the successful construction of diatomic Fe-N 4 /Co-N 4 sites. The FeCo-N-C exhibits a higher normalized reaction rate (2.07 × 105 min−1 mol−1) in BPA removal than previously reported SACs. Low-temperature electron paramagnetic resonance analysis reveals that Fe-N 4 and Co-N 4 process different intrinsic properties (spin states), which may lead to their diverse functions in the PDS activation process. The Co sites can significantly accelerate electron transfer and enhance the PDS adsorption abilities. As a complement, Fe sites perform better in the electrostatic interaction and destabilization of PDS. This study not only explains the synergy of multi-functional diatomic sites from the whole PDS activation process but provides a reliable reference for the elimination of emerging organic contaminants. [ABSTRACT FROM AUTHOR]

[Display omitted] • 2Fe–NC with three-dimensional flower shape and mesoporous structure was developed via facile pyrolysis. • 2Fe–NC possesses the catalytic performance of a nanozyme with a mononuclear Fe active site. • Fe(IV) O is the main contributor to the degradation of CAP in the 2Fe–NC@PDS system. • 2Fe–NC acts as a shuttle that mediates the electron transfer from organic substrates to PDS. The high-valent iron-oxo species (Fe(IV) O) exhibit great prospects for the removal of organic contaminants in iron-mediated persulfate activation. Nevertheless, an adequate research of the mechanisms involved in Fe(IV)-based activation processes and organic degradation remains elusive. Here, an Fe encapsulated in N-doped carbons catalyst (2Fe–NC) with three-dimensional flower shape and mesoporous structure was developed, which can 100 % remove various organic pollutants such as chloramphenicol (CAP), sulfamethoxazole, amoxicillin, benzoic acid, and bisphenol A within 30 min by peroxydisulfate (PDS) activation. In the oxidation system, 2Fe–NC as an electron transfer medium was critical to mediate electron transfer from organic compound to PDS, accompanied by the redox cycle of Fe(IV)/Fe(II) and Fe(IV)/Fe(III). Multiple experiments reveal that the oxidation mechanism of 2Fe–NC@PDS system is similar to the dioxygen activation mechanism of binuclear active sites, which activates PDS to form surface-active Fe(IV) O species without producing radicals. The two pathways of CAP degradation simulated by density functional theory calculations release 6.92 and 4.23 eV, respectively, which is thermodynamically favorable. Overall, the new insights gained in this work offer a significant route to design more effective advanced oxidation processes for refractory contaminant treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • The g-C 3 N 4 was prepared from six different precursors to activate H 2 O 2 , PMS and PDS. • The structural and photoelectric properties were influenced by the precursors. • g-C 3 N 4 prepared by trithiocyanuric acid showed the best photocatalytic performance. • g-C 3 N 4 prepared by urea was the most suitable for peroxide activation. • •OH and 1O 2 were the dominant ROS in PDS and PMS related processes, respectively. In this study, g-C 3 N 4 catalysts were prepared from six different precursors including urea, melamine and its hydrochloride, dicyandiamide, thiourea, trithiocyanuric acid to compare their photocatalytic performance and the activation of three commonly seen peroxides, i.e., H 2 O 2 , peroxymonosulfate (PMS), and peroxydisulfate (PDS) under visible light irradiation. The structural and photoelectric properties were analyzed systematically. Results showed that the g-C 3 N 4 synthesized from trithiocyanuric acid (TCA-CN) showed the largest SSA (56.59 m2/g), the narrowest band gap (2.621 eV), and lowest carriers' recombination rate, which correspondingly exhibited the best photocatalytic performance for the degradation of bisphenol A (BPA). Moreover, the g-C 3 N 4 synthesized by urea (U-CN) demonstrating the strongest photoelectron density, widest band gap (2.790 eV) and the most positive VB potential showed the highest activating efficiencies of all three oxidants. In general, persulfates were more competent to enhance the degradation of BPA than H 2 O 2 , and PMS showed the highest activity. The dominant reactive oxidation species (ROS) depended more on the type of peroxides than on the catalyst precursors. The effective activation of PDS by U-CN was primarily resulting from the photoelectrons to produce extra •OH to enhance compounds degradation, and high yield of 1O 2 could be achieved by PMS activation through h+ oxidation, leading to the most significant enhancement of BPA removal. The N–C 3 and NH x of U-CN were likely the sites for PMS activation. Moreover, the U-CN/LED/PMS process showed the strong adaptability to the complex water environment. This work may provide new insights into selecting highly efficient g-C 3 N 4 -based advanced oxidation processes for water remediation. [ABSTRACT FROM AUTHOR]

Carbon vacancies and Rh 2 O 3 nanoparticles were sequentially introduced into CN to accelerate photo-generated electron and hole transfer simultaneously, and the effect of defect and cocatalyst on the photodegradation process was systematically analyzed, resulting in high performance of degradation 10 ppm BPA within 15 min under visible light condition. [Display omitted] • Ultrafine Rh 2 O 3 nanoparticles (∼5 nm) are dispersed on the surface of CN. • The C vacancies and Rh 2 O 3 can respectively promote the transfer of electrons and holes to inhibit the recombination of excitons. • V C -CN 7.5 -Rh 2 O 3 -900 can degrade 10 ppm BPA in 15 min showing excellent degradation rate. The sluggish charge transfer and fast recombination of charge carriers is a determining factor limiting photocatalytic efficiency of carbon nitride. Herein, carbon vacancies and Rh 2 O 3 nanoparticles were sequentially introduced into CN to accelerate photo-generated electron and hole transfer simultaneously, thereby improving the photocatalytic performance of CN to achieve the complete removal of Bisphenol A (BPA) in 15 min. Mechanism analyses reveal that the modification of the carbon vacancies regulates the active charge carriers, excitons and trap states, thus enhances the carrier separation capabilities and light absorption. Meanwhile, the in situ photodeposited Rh 2 O 3 nanoparticles, as a hole-transfer mediator, maximally suppress recombination of photogenerated charges. These synergistic effects result in promoting the separation and transfer of charge carriers and thus improving photocatalytic performances. This strategy can serve as guideline for the reasonable design of efficient photocatalysts for phenolic wastewater remediation. [ABSTRACT FROM AUTHOR]

In order to improve the photocatalytic activity of In-based metal organic framework (MOF) materials (In-MOF) with H 4 TBAPy as ligand, we constructed a novel Z scheme plasma photocatalyst Ag/Ag 3 PO 4 /In-MOF (A/AP/In). The improved photocatalytic activity is mainly due to the presence of Z-type heterojunctions and Ag particles that enable efficient migration and separation of photogenerated carriers, while the surface plasmon resonance (SPR) effect generated by Ag nanoparticles can promote the visible light absorption of the composite. Ultimately, A/AP/In retains the large specific surface area of In-MOF and provides abundant reactive sites, thus achieving efficient adsorption and degradation of BPA. [Display omitted] • Large specific surface area and strong π-π interaction bring enhanced adsorption capacity. • Ag NPs can produce surface plasmon resonance (SPR) effect and promote visible light absorption. • Z-type heterojunctions and Ag NPs can efficiently boost migration and separation of photogenerated carriers. • The synergistic effect of adsorption and photocatalysis achieved efficient removal of BPA. Refining the visible light absorption and optimizing the separation of photogenerated electron-hole pairs are pivotal in enhancing the photocatalytic activity of composites. A novel Z-scheme plasma photocatalyst, Ag/Ag 3 PO 4 /In-MOF (A/AP/In), was developed in this study. Experimental results demonstrated that A/AP/In exhibited the highest photocatalytic activity for BPA among all samples tested, achieving complete degradation of 50 ppm BPA within 30 min, as well as its apparent degradation rate was about 11 times higher than that of pure Ag 3 PO 4 and 4 times higher than that of pure In-MOF. The enhanced photocatalytic activity can be mainly attributed to the existence of Z-type heterojunctions and the surface plasmon resonance (SPR) effect induced by Ag nanoparticles, which facilitate efficient migration and separation of photogenerated carriers. Meanwhile, the incorporation of Ag nanoparticles enhances visible light absorption and protects Ag 3 PO 4 from photocorrosion in the composites. Moreover, A/AP/In maintains the large specific surface area of In-MOF and provides abundant reactive active sites. In addition, the photocatalytic performance of A/AP/In was above 90 % after five consecutive cycles confirming its good stability. Overall, this study proposes a novel approach for constructing bifunctional composites with efficient adsorption/catalytic degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Iron/carbon composites derived from solid waste were applied in PMS activation. • FeAC-950/PMS exhibited an excellent activity for BPA elimination. • SO 4 •− plays dominant role in BPA removal compared with electron-transfer process. • FeAC-950/PMS system shows good performance to oxidize various organic pollutants. Efficient and low-cost catalysts are important for contaminant remediation in peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs). In this study, a solid waste, generated by the polyferric chloride coagulation of the phenol-saturated powder activated carbon from an industrial wastewater treatment plant, was used to prepare metal/carbon composites under different pyrolysis temperatures (650–950 °C). The catalyst pyrolyzed at 950 °C (FeAC-950) exhibited the highest reactive activity for PMS activation as demonstrated by a series of electrochemical techniques. Nearly complete BPA elimination can be achieved within 60 min by 0.1 g L–1 FeAC-950 and 0.5 mM PMS. The results of electron paramagnetic resonance (EPR), chemical quenching and open circuit potential (OCPT) experiments demonstrate a combined radical and non-radical oxidation mechanism in the FeAC-950/PMS process and BPA was removed dominantly through radical pathway. Various persistent organic pollutants can be efficiently eliminated in the FeAC-950/PMS system. In addition, the present system showed good tolerance to natural organic matter as well as some common anions such as chloride and nitrate. This study dedicated a simple method to prepare an efficient solid waste-based catalyst in environmental catalysis. The outcomes will not only provide a value-added reuse approach for waste management but also facilitate the FeAC-950 applications in wastewater remediation technologies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Developed a newly, greenly, low-cost strategy to reuse waste PET plastics. • Fe-MOF was in situ growth on the surface of waste PET substrate by PDA-treated. • MOF composites show good catalytic ability to DBPs in the photo-Fenton system. • Intermediates were identified and potential degradation routes of DBPs were proposed. Drinking water disinfection processes have made remarkable contributions to keeping drinking water safe. However, these processes can lead to the formation of numerous harmful disinfection by-products (DBPs). Therefore, it is crucial to implement effective measures to minimize the production of DBPs. Herein, PET@PDA@NH 2 -MIL-53(Fe) (PNM) composite was successfully prepared via surface etching and solvothermal method. The material exhibited excellent photocatalytic activity for DBPs and their precursors at the photo-Fenton system formed by PNM and trace H 2 O 2 , which system achieved 99% degradation of 2,6-dichloro-1,4-benzoquinone (2,6-DCBQ) in 30 min, and more than 98% and 95% degradation of phenol and bisphenol A (BPA) in 60 min. The PNM shows more than 90% degradation of DBPs even in real water. Based on free radical trapping experiments, a possible catalytic mechanism was proposed. ·OH and holes were the main active species in the catalytic process. Meanwhile, using UPLC-QTOF and GC–MS to identify intermediate degradation products and Toxtree software to assess toxicity. The PNM maintained a degradation rate over 95% after 5 cycles which demonstrates a remarkable recyclability. This study achieves the reuse of waste PET and opens a new way in exploring the development of eco-friendly photocatalytic materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • An impregnation–calcination route is proposed to prepare FeQDs/TiO 2−x. • The obtained FeQDs/TiO 2−x exhibited quasi−full visible light absorption. • The lifetime of the photogenerated electrons in the catalyst was greatly prolonged. • Efficient Fe3+/Fe2+ cycling was observed on the surface of Fe3+/Ti3+ co−doped TiO 2. • Synergistic effects between Fe3+/Ti3+ doping improved the catalytic performance. In this work, a facile impregnation–calcination route was proposed for the synthesis of Ti3+ self−doped TiO 2 anchored with iron oxide quantum dots (FeQDs/TiO 2−x) as an efficient visible light−derived persulfate catalyst for organic degradation. After the successful co−doping of Fe3+ and Ti3+, the obtained FeQDs/TiO 2−x exhibited quasi−full visible light absorption, with the maximum absorption edge broadened to 791 nm; furthermore, its charge separation and interfacial transport capacity were significantly enhanced, as evidenced by the fact that the lifetime of the photogenerated electrons was prolonged from 6.17 to 10.34 ns. In addition, the surface Fe3+ species on FeQDs/TiO 2−x can be effectively reduced to Fe2+ by the separated electrons, establishing an efficient cycle between Fe3+ and Fe2+. Therefore, the obtained FeQDs/TiO 2−x nanocomposite exhibited enhanced catalytic performance for the degradation of phenolic pollutants via PS activation under visible light. Specifically, 50 mg/L bisphenol A (BPA) and acetaminophen (AAP) can be completely degraded by FeQDs/TiO 2−x with faster reaction rate constants and higher mineralization rates compared to its counterparts, including TiO 2 , TiO 2−x , and FeQDs/TiO 2. Based on the results of material characterization, degradation experiments, identification of reactive oxidizing species, and chemical quenching experiments, the mechanism of the enhanced photocatalytic activity of FeQDs/TiO 2−x was elucidated. Our results demonstrated the high potential of FeQDs/TiO 2−x for wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Fe-N-C content of FCF-A composites can be precisely controlled can be precisely. • Two main routes of BPA degradation pathway were investigated by DFT calculations. • The synthesized FCF-0.05 exhibited great potential for practical application. Graphitic carbon nitride (CN) is a promising photocatalyst in wastewater treatment field; however, CN suffers from sluggish photogenerated charge separation. Herein, a single atom catalyst (Fe-N-C) coupled with ferrocene-functionalized CN (CN-Fc) heterostructured composite (FCF-0.05) with superior photocatalytic activity was fabricated. Bisphenol A (BPA) can be removed completely over FCF-0.05/PMS/Vis system within 60 min, the corresponding apparent rate constant (k) was 24 times and 10 times higher than those of CN/Vis and CN/PMS/Vis systems, respectively, which was derived from the efficiently charge separation since generated interfacial heterojunction. Moreover, FCF-0.05/PMS/Vis system exhibited high stability and superior catalytic activity in real water and outdoor environment. Furthermore, the BPA degradation mechanism and pathway have been identified by combination experimental (quench testing, electron paramagnetic resonance and liquid chromatography-mass spectrometry techniques) and density functional theory (DFT) calculations method, providing insight of synthesis of cost-effective photocatalyst with outstanding catalytic activity. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Combination of an electrochemical process equipped with Zn sacrifice anode with visible light. • In situ generation of ZnO nanoparticles as a results of anode corrosion. • Achieving an innovative combination of electrochemical and photocatalytic processes. • Synergistic degradation of bisphenol A (BPA) through the hybrid process. Abstract In the present study, an innovative combination of electrochemical and photocatalytic processes with significant synergy was considered to destroy bisphenol A (BPA) as model endocrine disrupting compound. For this purpose, in situ electro-generated ZnO nanoparticles due to the corrosion of sacrificial Zn anode played the photocatalyst role under visible light irradiation. X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Brunnaer–Emmett–Teller (BET), photoluminescence (PL) and UV–Vis diffuse reflectance spectra (DRS) results exhibited the formation of ultrafine crystalline ZnO nanoparticles with appropriate optical properties. A higher synergy factor was obtained by the combination of aforementioned electrochemical and photocatalytic processes relying on the electro-generated ZnO nanoparticles in BPA-contained solution. In the presence of chemical enhancing compounds such as solid hydrogen peroxide and Oxone, the degradation of BPA increased from 84 to 90.5 and 97.5% within 2 h, respectively. The complete elimination of BPA was attained during the elapsed time of 90 min when ultrasound was applied. The results of bio-toxicity assay, based on the application of biosolids as the source of living microorganisms, revealed that the hybrid process could decrease the specific oxygen consumption inhibition (I SOUR) of the BPA from 31.3 to 18.8%. [ABSTRACT FROM AUTHOR]

Graphical abstract MnO x quantum dots decorated nitrogen-doped hollow carbon shells were synthesized as robust and enhanced heterogeneous catalyst for peroxymonosulfate activation. Highlights • MnO x QDs decorated N-doped hollow porous carbon was synthesized by a facile strategy. • MnO x /N-HPCS outperformed other benchmark catalysts for PMS activation to degrade BPA. • Excellent universality, recyclability and stability of MnO x /N-HPCS were obtained. • Mn-OH, valence variation of Mn, and metal-free N-doped carbon sites induced ROSs. Abstract Manganese oxide (MnO x) with earth-abundance and low toxicity have received considerable interest for advanced oxidation processes (AOPs) but suffer from poor catalytic activity and stability. Herein, a unique hybrid hollow structure with ultrasmall size MnO x quantum dots (QDs, ∼3 nm) homogeneously dispersed on N-doped porous carbon shells (denoted as MnO x /N-HPCS) was designed as heterogeneous Fenton-like catalyst. The ultrafine nanoscaling morphology of MnO x QDs enlarges its specific surface area (227.9 m2/g) for providing more active sites. The N-doped carbon (NC) shells can not only greatly improve the conductivity of the hybrid and effectively prevent the aggregation of MnO x QDs, but serve as metal-free active sites for Fenton-like reaction. While the hollow porous structure enables the fast transportation of reactants access to the full-exposure active sites. When evaluated as catalyst for peroxymonosulfate (PMS) activation, the MnO x /N-HPCS hybrid outperformed other benchmark catalysts toward the removal of bisphenol A (BPA) with highest removal rate of 0.29 min−1. Results showed that exceed 99% of BPA (10 mg L−1) was removed within 20 min at the dosage of 0.2 g L−1 PMS and 0.06 g L−1 MnO x /N-HPCS. Moreover, the mechanism of PMS activation by MnO x /N-HPCS was studied. The mixed valence states of Mn, the hydroxyl species induced complexation of Mn(3+/4+)-PMS and the metal-free N-doped sites synergistically enhancing the generation of reactive oxygen species (OH and SO 4 −). Furthermore, the MnO x /N-HPCS catalyst also displayed good reusability (successive 4 runs) with negligible Mn leaching (less than 2 μg L−1). Together with the investigation of the application in real environment water samples (such as tap water and wastewater), we demonstrated this novel Mn-based AOPs catalyst with unique structure and high activity will hold great potential in environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • First synthesis of polyethyleneimine (PEI)/BiOBr semiconductor organic framework (SOF). • Bonding and intercalation of PEI enhance the BPAF photocatalytic degradation actively. • BPAF toxicity decreased after degradation confirmed by zebrafish exposure experiment. • Mutual validation of degradation products toxicity prediction and zebrafish toxicity test. Photocatalysis is a promising method for water pollution treatment, but it is challenged due to its low efficiency and insufficient understanding of the toxicity after degradation. In this work, we construct a polyethyleneimine-enhanced BiOBr semiconductor organic framework (PEI/BiOBr SOF) by utilizing PEI's bonding and intercalation effects. PEI/BiOBr SOF enhances the photocatalytic degradation of bisphenol AF (BPAF) at a reaction rate 10 times that of BiOBr. Under the dual effects of intercalation and bonding, PEI/BiOBr SOF can realize extended the light absorption, increase the specific surface area and surface-active sites, inhibit carrier complexation, and promote the production of reactive oxygen species. The toxicity changes of the BPAF were evaluated by combining chemical product analysis and biological toxicity experiments. The mutual validation of the toxicity prediction results of the ECOASR product and the zebrafish toxicity experiment confirmed that the toxicity of BPAF decreased after degradation. Furthermore, the mechanism of photocatalytic degradation and detoxification of BPAF with PEI as the circuit of charge transmission of the BiOBr SOF was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel β-cyclodextrin polyurethane hyper-crosslinked polymers (CDPU-HCP) was prepared for BPA removal. • The high surface area of CDPU-HCP was obtained by Friedel-Crafts alkylation reaction. • The micropores of CDPU-HCP promote the diffusion and capture most of BPA. • The maximum adsorption capacities of BPA are 371.8 mg∙g−1 by CDPU-HCP. Bisphenol A (BPA) is a common industrial products ingredient, whose widespread utilization leads to a non-negligible problem of water pollution. For efficient adsorption of BPA, hyper-crosslinked β-cyclodextrin polyurethane (CDPU-HCP) was synthesized via crosslinking β-cyclodextrin (β-CD) with 4,4′-diphenylmethane diisocyanate followed by further external crosslinking reaction. CDPU-HCP showed high surface area (1133.12 m2∙g−1) and has hierarchically pores, such as β-CD nanocavities, micropore and mesopores. Adsorption data fitted better with Freundlich adsorption isotherm model and the pseudo second order kinetic model. The fitted maximum adsorption capacity toward BPA was shown to be 371.8 mg∙g−1. The stable adsorption performance during successive six recycling experiments indicated the excellent recyclability of CDPU-HCP. Furthermore, the density functional theory (DFT) calculations showed hydrophobic interaction of β-CD cavity and π-π interactions between aromatic moieties and BPA synergistically promoted the adsorption process. Therefore, CDPU-HCP was suggested to be a promising adsorbent in the treatment of BPA. [ABSTRACT FROM AUTHOR]

[Display omitted] • KH570 dispersed Ag nanoparticles well on the surface of TiO 2 NTAs. • KH570 anchored Ag+/Ag0 firmly during photocatalytic activation of PMS process. • Ag/KH570/TiO 2 NTAs/PMS/VL system had a superior organics removal. • Ag/KH570/TiO 2 NTAs showed excellent catalytic stability. To enhance the photocatalytic activation of peroxymonosulfate (PMS), the precious metal was used to modify the catalyst. However, the catalyst suffered from metal leaching due to the oxidation of zero-valent metal into the ionic state by PMS. Herein, the silane coupling agent, KH570, was selected to fix metal Ag on the surface of TiO 2 nanotubes arrays (TiO 2 NTAs) firmly and dispersedly. The prepared Ag/KH570/TiO 2 NTAs were efficient visible-light (VL) photocatalytic PMS activators for the degradation of bisphenol A (BPA). The Ag/KH570/TiO 2 NTAs/PMS/VL system exhibited a higher degradation rate (k obs = 0.1 min−1) and exceptional stability even after 30 cycles (0.098 min−1) compared to Ag/TiO 2 NTAs/PMS/VL system (0.074 and 0.015 min−1 for first and fourth use, respectively). KH570 well-dispersed Ag0 on the surface of TiO 2 NTAs showed significantly enhanced VL absorption, photo-generated current, and electro-transfer ability, which boosted PMS activation. The Ag0 also activated PMS and converted to Ag+, which was quickly reduced to Ag0 again by photo-generated electrons. KH570 well-immobilized Ag0/Ag+ promoted above catalytic cycles with minimal Ag leaching. Activation of PMS by the photo-generated electrons and Ag0 resulted in the generation of •OH and SO 4 •−, which seized the principal position for BPA removal. The wide pH adaptability and production of more oxidant in water matrixes (Cl−, HCO 3 −, and humic acid) enabled Ag/KH570/TiO 2 NTAs/PMS/VL system to exhibit excellent performance in the actual waterbodies (groundwater and tap water). This work would provide useful information in the construction of stable zero-valent metal modified catalysts for the (photo)catalytic activation of PMS/persulfate. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe doped porphyrin-based porous organic polyme (Fe@PrPOP) was facilely prepared with hierarchically porous structure and highly dispersive Fe atoms. • Fe@PrPOP exhibited excellent periodate activation performance. • Nonradical reaction pathways including 1O 2 and electron transfer were identified. • Fe@PrPOP catalyst presented high stability, reusability and adaptability. Developing efficient and stable catalysts for periodate (PI) activation is important for the abatement of emerging contaminants. Herein, Fe doped into polyprophyrin-based porous organic polymer (Fe@PrPOP) was prepared via a facile one-step reaction, and its catalytic capacity and reaction mechanism for PI activation were systematically investigated. Complete removal of bisphenol A (BPA) was achieved within 12 min under the Fe@PrPOP/PI system within a wide pH range (3–8), as well as no leaching of Fe was observed throughout the reaction. Nonradical pathways, including 1O 2 and electron transfer, were identified for the BPA removal. According to substantial characterizations and density functional theory calculations, we concluded that the scattered Fe species on the surface of Fe@PrPOP were the main active sites, which was conducive to the adsorption and activation of PI. In addition, the Fe@PrPOP/PI system exhibited selective oxidation toward various organic pollutants with electron-rich moieties. Overall, this study provides a promising alternative in activating PI for the removal of organic compounds in water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nitrogen-doped carbon with high activity for BPA degradation via PMS activation was prepared. • A free radical/non-radical process dominated by SO 4 •- and 1O 2 caused the formation of free radical intermediates. • The deactivation of N-doped carbon resulted from a free radical grafting reaction. Nitrogen-doped carbon has been established as an effective catalyst for peroxymonosulfate (PMS) activation to remove pollutants from water. However, the easy deactivation during the reaction process limits its potential for widespread application. In this study, nitrogen-rich carbocatalysts was synthesized by two-step pyrolysis and used to activate PMS for degradation of bisphenol A (BPA). The nitrogen-rich catalysts calcined at 900 ℃ with the amount of 2 mg degraded more than 80 % of 20 mg/L BPA in 20 min and the degradation of TOC has reached 65 %, showing excellent catalytic performance. Based on free radical quenching experiments and electron spin resonance (ESR), the non-radical process played a key role in BPA degradation. The characterization results of fresh and used catalysts suggested that the instability of the nitrogen-rich carbon materials resulted from the grafting reaction between free radicals on the graphite carbon site of the N -doped carbon materials and the intermediate degradation products of BPA, which covered the active sites of the catalysts. This new discovery elucidates the reason of N -doped carbon materials deactivation in PMS oxidation and provides a complementary for the reaction mechanism of carbon catalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • The composite with Fe/Fe 3 C nanoparticles embedded into N-doped porous carbon was fabricated. • Fe/Fe 3 C@NPC could be utilized as the heterogeneous electro-Fenton catalyst cathode. • Highly efficient BPA degradation performance was achieved in the electro-Fenton system. • BPA removal mechanism was systematically investigated. Heterogeneous electro-Fenton is a promising technology for the degradation of organic contaminants. To ensure its effectiveness, it is in urgent demand to design cathode materials with the integrated capability of sufficient H 2 O 2 generation and subsequent activation into reactive oxygen species (ROS) together with catalytic stability. Herein, a composite constituted by Fe/Fe 3 C nanoparticles embedded into N-doped porous carbon (NPC), designated as Fe/Fe 3 C@NPC, was successfully fabricated from Fe3+-loaded poly(imine dioxime) (PIDO) membrane via the thermal treatment in N 2 atmosphere and employed as the heterogeneous electro-Fenton catalyst to degrade bisphenol A (BPA). By optimizing the pyrolysis temperature and loading level of iron species, the catalyst obtained at 800 °C (i.e. Fe/Fe 3 C@NPC-800) achieved almost 100% of BPA removal efficiency within 120 min via the electro-Fenton system, accompanied by 69.2% of the total organic carbon (TOC) removal rate. Furthermore, the proposed composite catalyst also exhibited satisfactory reusability and stability, as reflected by low decrease in removal efficiency after six successive degradation tests and limited iron leaching (<0.5 mg/L). This work might provide valuable instruction for the rational design of highly efficient and stable heterogeneous electro-Fenton catalysts for organic pollutant control. [ABSTRACT FROM AUTHOR]

[Display omitted] • The combination of AOPs and membrane achieves 98 % naproxen removal. • AOP efficacy is inhibited by naproxen adsorption, caused by a pH drop after adding PMS. • Restoring the original pH, directly after adding PMS, results in a 23-fold increase in degradation rate. • Chemically cleaning mitigates inhibition and restores catalytic functionality. In this work, catalytic membranes were fabricated by blending CoFe 2 O 4 catalysts into polyethersulfone (PES) and then used to treat naproxen with the addition of peroxymonosulfate (PMS). It was found that the addition of PMS results in a decrease in pH, which increases the adsorption of naproxen. This often overlooked phenomenon is demonstrated here to have an important role since the adsorption of naproxen on the polymeric matrix and catalytic particles decreases the degradation efficiency of naproxen. To verify this hypothesis and rule out the decrease in pH after the addition of pH, two ways of controlling the pH of the naproxen solution were compared: adjusting pH before and after the addition of PMS, respectively. Our results indicate that in the batch experiment, adjusting the pH of naproxen solution after adding PMS led to a dramatic 23-fold increase in the kinetic constant of the naproxen oxidation (0.42/min, pH6) compared to when pH was adjusted before adding PMS (0.018/min, pH 6). This enhancement in the overall kinetics was attributed to the elimination of the inhibition caused by MPs adsorption at low pH. In a dead-end cell, the catalytic membranes with 2.0 % of CoFe 2 O 4 achieved quantitative conversion of naproxen, bisphenol A, and atrazine, with values of 98 %, 97 %, and 74 %, respectively, demonstrating the efficacy of this approach to convert multitype of MPs in wastewater streams. In a reusability study, the naproxen removal of the catalytic membranes with 2.0 % of CoFe 2 O 4 decreased by 81 % and 45 % after 5 rounds in the batch experiment and dead-end cell, respectively. However, with a chemical cleaning process between each round, the degradation efficiency can be effectively recovered, proving the negative effects of the adsorption of MPs or their intermediates during the SR-AOPs. Our work demonstrates that pH in SR-AOP-based catalytic membrane processes determined both the reaction rate and the adsorption of MPs or their intermediates on the membrane and its reactive sites. We envision that these results will be valuable in developing efficient catalytic membranes for the treatment of MPs in wastewater streams. [ABSTRACT FROM AUTHOR]

A new hyper-crosslinked β -cyclodextrin porous polymer, HCP(BnCD-DCX), was synthesized by crosslinking benzylated β -CD (BnCD) with dichloroxylene (DCX) via a Friedel-Crafts alkylation route. The polymer showed high surface area and thermal stability, making it an efficient adsorbent for the removal toward bisphenol A from water. The adsorption process of bisphenol A on the polymer followed the pseudo-second-order model and Langmuir isotherm model. The maximum adsorption capacity of bisphenol A on HCP(BnCD-DCX) was calculated to be 278 mg g −1 at 25 °C. Host-guest and π-π interactions between bisphenol A and HCP(BnCD-DCX) contributed to the high adsorption capacity. Moreover, the peak pore size distribution of the polymer (1.3 nm) matched well with the maximum molecular z length of bisphenol A, also benefitting for the adsorption efficiency. Our strategy may open a new avenue for designing various hyper-crosslinked polymers for water treatment. [ABSTRACT FROM AUTHOR]

Degradation of bisphenol A (BPA), an industrial chemical and suspected endocrine disruptor, in a pulsed discharge plasma (PDP) system combined with activated carbon (AC) was investigated in this study. The experimental results showed that the degradation rate of BPA could reach 95.3% after 60 min discharge plasma treatment at 20 kV discharge voltage and the degradation process fitted the first-order kinetic model; degradation rate of BPA was higher in acid solution than that in neutral or alkaline solution; compared to air and nitrogen, the degradation rate of BPA was highest when oxygen was bubbled into the reaction system; the results of spectrum detection indicated the synergistic effect of PDP and AC and the important role of OH and O for the degradation of BPA; the removal of TOC could be 36.8% at the optimal condition; longer discharge plasma treatment time resulted in lower pH value and higher conductivity of treated solution; the increase of absorbance at 240–260 nm in UV–Vis spectra of the BPA solution illustrated the production of intermediates during the degradation process; the degradation pathway was proposed based on the research results and references. Scanning electron microscope (SEM) analysis showed that the surface of the AC after PDP treatment was smoother and AC could be generated by pulse discharge under a certain condition. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe-doped g-C 3 N 4 (Fe/CNSP) is synthesized by supramolecular preorganization. • Combination of photogenerated carriers is suppressed due to thin nanosheet structure. • The reduction of Fe(III) to Fe(II) is accelerated by the photogenerated charges. • Photo-Fenton activity of Fe/CNSP is enhanced obviously compared with bulk Fe-g-C 3 N 4. • The CBZ degradation pathways are proposed and the product toxicity is analyzed. The photo-Fenton process, with a synergistic effect of Fenton oxidation and photocatalysis, is a promising technique for the removal of refractory organic pollutants. However, the rapid recombination of photogenerated charge carriers results in less electrons for Fe(III)/Fe(II) cycle and later generation of hydroxyl radicals. In this work, Fe-doped graphite carbon nitride with a thin nanosheet structure (∼5 nm thickness) was prepared using the supramolecular preorganization method (Fe/CNSP), which effectively suppresses the recombination of photogenerated charges compared with that of Fe-doped bulk carbon nitride (Fe/BCN), resulting in an obviously improved photo-Fenton performance by increasing the electron gain at the Fe sites and the speed of the reduction of Fe(III) to Fe(II). The heterogeneous photo-Fenton activity of Fe/CNSP displays a 6.5 times higher kinetic constant for carbamazepine degradation than that of Fe/BCN, and universal effectiveness toward other organic pollutants, namely phenol, sulfamethoxazole, bisphenol A, and 2,4-dichlorophenol, with TOC removals between 37.4% and 91.3% in 150 min. OH, O 2 −, e−, h+, and 1O 2 contribute to the degradation of organic pollutants. Fe/CNSP was proven to be stable and reusable in cyclic experiments. The analysis of the intermediate toxicity demonstrated that the Fe/CNSP photo-Fenton system effectively reduced the toxicity of carbamazepine. This study offers a simple, highly reproducible method for developing efficient heterogeneous photo-Fenton catalysts. [ABSTRACT FROM AUTHOR]

Three-dimensional carbon nitride co-modified by oxygen doping and nitrogen vacancies on peroxydisulfate activation for pollutants degradation and photocatalytic transfer hydrogenation of nitrophenols. [Display omitted] • Surface electron density on PEPE-C 3 N 4 was enhanced by oxygen doping and nitrogen vacancies. • 1% PEPE-C 3 N 4 exhibits excellent performance in PDS photocatalytic activation. • In-depth exploration of the intermediate products during the photodegradation. • The photodegradation mechanism for BPA and MBT by PEPE-C 3 N 4 was proposed. • The mechanism of transfer hydrogenation with water as hydrogen source was revealed. A three-dimensional carbon nitride co-modified through oxygen doping and nitrogen vacancies was prepared via an ordinary hydrothermal and thermal polymerization reaction of dicyandiamide and polyethylene glycol-polypropylene glycol-polyethylene glycol triblock copolymer (PEPE-C 3 N 4). The electronic structure of carbon and nitrogen was proven through solid-state nuclear magnetism and electron loss energy spectroscopy. Density functional theory calculations revealed reduced band gap and altered charge density. The results show that the PEPE-C 3 N 4 constructed by O-doped and nitrogen vacancy released electrons to activate peroxodisulfate (PDS), in which the 1% PEPE-C 3 N 4 in the photocatalytic PDS system showed about 12 and 30 times increase of the photodegradation of 2-mercaptobenzothiazole (MBT) and bisphenol A (BPA), respectively, compared to graphite-phase carbon nitride (g-C 3 N 4). The degradation products of MBT and BPA were named according to applying liquid chromatography-mass spectrometry and conceivable degradation pathways proposed. Furthermore, 1% PEPE-C 3 N 4 had the highest hydrogen production activity (8275.74 μmol•h−1•g−1); it completely hydrogenates 4-nitrophenol to 4-aminophenol after 2.5 h of simulated sunlight. Additionally, biomass was used instead of TEOA to measure the coupling operation of H 2 generation and selective oxidation of 5-hydroxymethylfurfural (HMF) to 2, 5-furandicarboxaldehyde (DFF). The optimized PEPE-C 3 N 4 demonstrated high efficiency for selective oxidation of HMF to DFF with simultaneous H 2 co-production (1176.84 μmol•h−1•g−1 for H 2 and 357.67 μmol•h−1•g−1 for DFF), 5.31 and 2.36 times more excellent than that of g-C 3 N 4 , respectively. This study outlines a way to devise photocatalysts for organic pollutant degradation and biomass value-added co-production of hydrogen. [ABSTRACT FROM AUTHOR]

[Display omitted] • SiO 2 @G1.5-IL can separate hydrophobic and hydrophilic substances. • The separation mechanisms include π-π stacking, hydrophobic, hydrophilic, hydrogen bonding, and electrostatic interaction. • SiO 2 @G1.5-IL has good extraction performance for hydrophobic analytes. • The online analytical method was established for the detection of PAHs. The efficient sample pretreatment and high-performance chromatographic separation are essential for an accurate analysis of the complex sample. Finding a material that can apply as both sorbent for sample preparation and stationary phase for chromatography is greatly important for analytical chemistry. With a large number of active sites and designable properties, the dendrimers displayed potential performance for sample preparation and chromatographic separation. In order to improve its selectivity restricted by the limited type of functional groups (amide, ethylidene, amino groups), ionic liquid (1,1′-(1,4-butyricdiyl)bis(1-aminopropyl imidazolium)dibromide) were introduced to functionalize dendrimers. With porous silica as the base, ionic liquid-functionalized dendrimer grafted silica (SiO 2 @G1.5-IL) was obtained and characterized by X-ray photoelectron spectroscopy, elemental analyzer, as well as specific surface and porosity analyzer. The material was used as stationary phase for mixed-mode chromatography and sorbent for SPE, respectively. Under reversed-phase liquid chromatography (RPLC), it successfully separated some hydrophobic analytes (five polycyclic aromatic hydrocarbons (PAHs), two bisphenols, diphenylpropane, and diphenylmethane), by utilizing hydrophobic, π-stacking and hydrogen bonding interactions. Based on the hydrophilic effect, it could separate hydrophilic analytes (nucleosides and alkaloids), which coincident with hydrophilic interaction liquid chromatography (HILIC). And it exhibited better separation capacity than NH 2 @SiO 2 and SiO 2 @G1.5 under the above two modes. Furthermore, the thermodynamic parameters (ΔH, ΔS, and ΔG) of the above types of analytes on the SiO 2 @G1.5-IL column were also investigated in detail, revealing the controlling factors during the chromatographic separation. And the relative standard deviations (RSDs, 0.03–2.95%, n = 10) of the repeatability of chromatographic separation were satisfactory. After that, SiO 2 @G1.5-IL-based SPE column was online combined with high-performance liquid chromatography to investigate the extraction selectivity for three types of hydrophobic organic pollutants (PAHs, estrogens, and bisphenols), and compared to SiO 2 and C18 columns. According to their extraction performance, PAHs were selected as the target analytes, and the online analytical method was established. The limits of detection were as low as 0.001 μg L-1 due to the high enrichment factor reach to 3869, limits of quantity were 0.003–0.17 μg L-1, linear ranges were from 0.003 to 15.0 µg L-1, the adsorption capacity was 16.10 μg g−1, as well as RSDs were 0.5–3.7%, 0.6–6.7%, and 4.2–9.0% for intraday, interday tests and reproducibility. Finally, it was applied to analyze the environmental water samples (tap water, snow water, and rainwater), and satisfactory results were obtained (spiked recoveries were 86.8%-120.9%). Therefore, SiO 2 @G1.5-IL was a powerful material that can be used for the chromatographic separation of both hydrophobic and hydrophilic samples by RPLC or HILIC mode, as well as the efficient online extraction of hydrophobic targets prior to C18 column-based high-performance liquid chromatography. [ABSTRACT FROM AUTHOR]

[Display omitted] • ▪ ZrO 2 -N bears Lewis acidic Zr4+, Brönsted acidic -OH, and mono -dentate NO 3 − (NO 3 - SUP). • ▪ NO 3 - SUP elevates acidic strengths of Zr4+/-OH to lower energy barrier of OH desorption for OH → NO 3 SUP. • ▪ ZrO 2 and ZrO 2 -N primarily use OH and NO 3 SUP in degrading pollutants, respectively. • ▪ ZrO 2 -N enhances efficiency/recyclability over ZrO 2 in aromatic degradation with poison accumulation evaded. • ▪ ZrO 2 -N outperforms α-MnO 2 -N in recycling textile wastewater mineralization with minute Zr leaching. To advance aqueous pollutant degradation using OH, H 2 O 2 (OH carrier) should be cleaved homolytically on a non-reducible metal oxide (ZrO 2) rather than heterolytically on a reducible counterpart (MnO 2), given the merits of H 2 O 2 homolysis such as improved OH productivity, unnecessity to recover H 2 O 2 activators (Lewis acidic metals; LA) via electron reduction, and minute LA leaching. This paper presents a methodology to exploit H 2 O 2 homolysis with the rate-determining step of endothermic OH desorption, thereby proposing the coupling of H 2 O 2 homolysis and exothermic radical inter-conversion of OH → NO 3 SUP (supported NO 3 ) to create the overall OH → NO 3 SUP route. ZrO 2 was modified with NO 3 − functionalities (NO 3 SUP precursors) to form ZrO 2 -N, where NO 3 - SUP species were located close to Zr4+ (LA) and Brönsted acidic -OH (BA) sites, whose acidic strengths must be elevated to facilitate OH desorption for reducing the energy barrier (E BARRIER) of the overall OH → NO 3 SUP route. NO 3 - SUP species were bound to the ZrO 2 surface via mono -dentate configuration only, thereby avoiding LA loss (rate in a per-gram↑), escalating LA/BA strengths (E BARRIER ↓), and imparting two free oxygens available to OH → NO 3 SUP (rate in a per-site↑). Moreover, NO 3 SUP species extract electrons from contaminants via electron transfer to recover NO 3 - SUP species used for recurring OH → NO 3 SUP , while sustaining pollutant fragmentation efficiency by circumventing surface poison accumulation. Hence, NO 3 SUP on ZrO 2 -N revealed higher efficiencies in fragmenting bisphenol A or recycling phenol degradation than OH evolved from ZrO 2. In addition, ZrO 2 outperformed MnO 2 in exploiting NO 3 SUP species, thus showing greater recyclability in mineralizing textile wastewater, while leaching a negligible amount of Zr. [ABSTRACT FROM AUTHOR]

Mg-Al-layered double hydroxide (Mg-Al-LDH) modified nanoscale zero-valent iron (NZVI) (Fe@MgAl-LDH) was firstly synthesized and characterized by several techniques. The results showed that the layered double hydroxides were coated on the surface of nanoscale zero-valent iron particles. This new material exhibited good adsorption for bisphenol A, 4-octylphenol and 4-nonylphenol from water samples. Based on these, a sensitive method was developed for the extraction and preconcentration of bisphenol A, 4-octylphenol and 4-nonylphenol using magnetic Fe@MgAl-LDH nanoparticles as the solid phase extraction adsorbents prior to high performance liquid chromatography coupled with variable wavelength detection. Under the optimal conditions, linear responses were achieved in the range of 0.5–200 μg L −1 with the correlation coefficients (r) above 0.999. The detection limits of three analytes were in the range of 0.24–0.34 μg L −1 , and precisions were all below 2.5% (n = 6). The proposed method was evaluated with real water samples and the excellent spiked recoveries in the range of 96.0–99.3% were achieved. [ABSTRACT FROM AUTHOR]

In this study, a duplex-structured SnO 2 -Sb-CNT composite anode (Ti/SnO 2 -Sb/SnO 2 -Sb-CNT) was fabricated using pulse electrodeposition technique. SnO 2 -Sb-CNT composite composed of 4–5 nm SnO 2 -Sb particles was synthesized via co-precipitation prior to the electrode preparation and characterized with BET and TEM. Characterization of Ti/SnO 2 -Sb/SnO 2 -Sb-CNT by FESEM, EDS, XRD, XPS, LSV, CV and EIS revealed that the novel duplex structured electrode had larger electroactive surface area and lower charge transfer resistance than conventional Ti/SnO 2 -Sb prepared by thermochemical decomposition, due to its more compact and rough surface. It also improved the electrochemical stability of Ti/SnO 2 -Sb/SnO 2 -Sb-CNT with a service lifetime up to 86 h. The oxygen evolution potential (OEP) of Ti/SnO 2 -Sb/SnO 2 -Sb-CNT was determined to be 2.2 V (vs Ag/AgCl). Bulk electrolysis of bisphenol A (BPA) was conducted to evaluate the electrocatalytic performance of the electrodes at various current densities (10–40 mA cm −2 ) and initial pH (3–11) of solution by determination of BPA degradation, total organic carbon (TOC) removal and mineralization current efficiency (MCE). Ti/SnO 2 -Sb/SnO 2 -Sb-CNT intended to adsorb more BPA molecules, which may contribute to its high current efficiency for electrochemical oxidation of BPA. The presence of humic acid (HA) could decrease the performance efficiency by inhibiting the adsorption of BPA by Ti/SnO 2 -Sb/SnO 2 -Sb-CNT. A mechanism is proposed to illustrate the enhanced degradation of BPA by Ti/SnO 2 -Sb/SnO 2 -Sb-CNT by synergistic adsorption and electrochemical oxidation. [ABSTRACT FROM AUTHOR]

A rapid and green synthesis of Cu-deposited N-doped TiO 2 /titanate nanotubes (TNTs) by the aid of microwave-assisted hydrothermal method was developed for the enhanced photocatalytic activity toward bisphenol A (BPA) degradation under UV and visible light irradiations. The TNTs are first synthesized at 150 °C for 3 h by microwave-assisted method followed by the calcination at 450 °C under NH 3 /N 2 atmosphere after the adsorption of 2–10 wt% Cu(II) ions to produce metallic Cu-deposited N-TiO 2 /TNTs nanocomposites. The microstructural analyses show that the Cu(II) ions are converted to Cu 0 in NH 3 /N 2 with mean particle sizes of 39–42 nm and N atoms are incorporated into the lattices of TiO 2 /TNTs. The Cu-deposited N-TiO 2 /TNT nanocomposites show the superior photoactivity toward BPA degradation under both UV and visible light irradiations. The photodegradation efficiency and rate of BPA increases upon increasing Cu amount and the optimal mass loadings of 8–10 wt% are obtained. In addition, the pseudo-first-order rate constants for BPA degradation increase 5.3–6.8 and 2.1–3.0 times under UV and visible light irradiations, respectively, when compare with those of Degussa P25 TiO 2 . The Schottky barrier between Cu 0 and N-TiO 2 promotes the electron transfer from N-doped TiO 2 to metallic Cu nanoparticles under UV and visible light irradiations, resulting in the efficient generation of prolonged oxygen-containing radicals for enhanced photodegradation of BPA. Results obtained in this study clearly open a new pave for the green synthesis of 1-dimensional metal-metal oxide nanophotocatalysts which can be potentially used in the fields of purification, green chemistry and photocatalysis. [ABSTRACT FROM AUTHOR]

The paper focuses on preparation of dual purpose porous prefilter that can serve either as a filter or sorbent for removal of bisphenol A. To obtain such materials, a possibility to form imprinted layer of methyl methacrylate and ethylene glycol methacrylate copolymer was evaluated. The layer was grafted to plasma activated porous polypropylene filters. It was noted formation of some patches on the surface for lower grafting yield. The patches increased their size up to formation of continuous layer. It was noted that optimization of grafting parameters should be performed separately and the use of the same protocol as for bulk polymerization of molecularly imprinted polymers could not be applied. The dual purpose prefilters were able to catch bisphenol A during filtration and its concentration was reduced significantly while other phenol derivatives were not adsorbed. By the use of molecularly imprinted filters, the removal of bisphenol A was four time higher than that removal on non-imprinted membranes. The best sorption properties were obtained for materials grafted by monomers with 4:6 M ratio of methyl methacrylate to ethylene glycol dimethacrylate. The static sorption reached the value of 0.06 mmol g −1 and bisphenol A was rejected at 70% level in filtration of 0.2 mM BPA aqueous solution. [ABSTRACT FROM AUTHOR]

In the present study, horseradish peroxidase (HRP) was employed to removal bisphenol A (BPA) with the presence of natural organic matter (NOM) and suspended solids (SS). Humic acid (HA) and kaolin have been selected as the typical NOM and SS in the experiment. According to the results, HA has shown a very interesting performance, which has both inhibitory and facilitation effects on BPA removal. For the low enzyme concentration (20 u/L and 50 u/L), small amount of HA could facilitate the BPA removal, while large amount of HA could inhibit the BPA removal. For the higher enzyme concentration (100–300 u/L), the addition of HA reduced the removal transformation of BPA and the inhibition effect of HA raised with the increase of HA concentrations. The facilitation nature of HA on enzyme catalytic processes can be attributed to the mitigation of enzyme inactivation, which has been proven by HRP inactivation rate. The inhibitory effect could be caused by the inhibition effect of HA on the enzyme activity, which has been suggested by both kinetic study and enzyme inactivation analysis. Kaolin showed a negative effect on BPA removal by HRP catalyzed reactions due to the inhibition effect of kaolin on HRP activity. The results have important implications for the engineering design by employing HRP in water and waste water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of a novel sulfhydryl-rich β-cyclodextrin polymer for wastewater treatment. • The adsorption process of Pb2+ was able to reach equilibrium rapidly within 60 s. • The theoretical adsorption capacity of Pb2+ and BPA reached 604.64 mg/g and 287.88 mg/g, respectively. • The different adsorption sites of Pb2+ and BPA lead to the excellent performance of the adsorbent in treating the mixed solution. • The adsorbent had excellent renewability and potential adsorption capacity for other pollution. At present, endocrine-disrupting chemicals (EDCs) and heavy metals (HMs) are increasingly polluting water. In this work, we prepared a sulfhydryl-rich β-cyclodextrin polymer (SH-CDP) for the adsorption of Pb2+ and bisphenol A (BPA), as the representatives of HMs and EDCs, respectively. SH-CDP have excellent adsorption performance with theoretical maximum adsorption capacity of 604.65 mg/g and 287.88 mg/g for Pb2+ and BPA, respectively. The adsorption process of Pb2+ by SH-CDP reaches equilibrium quickly within 60 s because of chelation between Pb2+ and sulfhydryl group, suggesting an ultra-fast adsorption rate. Since the adsorption sites of Pb2+ and BPA by SH-CDP are independent, the adsorption performance is still favorable under the coexistence of Pb2+ and BPA. Furthermore, SH-CDP maintains stable adsorption performance after five consecutive cycles. These results demonstrate that SH-CDP is a potential material capable of effectively treating HMs and EDCs in wastewater. [ABSTRACT FROM AUTHOR]