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The rapid development of nanoparticles (NPs) and their broad applications in medicine caused concerns about biological effects and biosafety. Here, the interaction of silver NPs (Ag NPs) and trypsin is studied with ultravioletvisible spectra, circular dichroism, and fluorescence spectra. Trypsin is exposed to various sizes and concentrations of Ag NPs. The intensities of the trypsin ultraviolet-visible absorption peaks are proportional to the Ag NP concentration and size. In the circular dichroism spectra, there was evidence that Ag NPs affected the secondary structure of trypsin. Fluorescence spectra show that the formation of the protein-nanoparticle complexes alters the protein chromophore chemical environment or structure and quenches its fluorescence. Hence, the extent of Ag NP binding of trypsin depends on both NP concentration and size, and changes the Ag NPs physicochemical properties as well as the trypsin secondary structure. With regard to nanomaterial safety, the interaction of NPs with proteins must be explored further for establishing NP toxicity and design guidance.

Carbon-based electrodes play important roles in constructing efficient capacitive deionization (CDI) devices. Therefore, the rational design of carbon materials with optimized structure, composition, and morphology is crucial for further improving the CDI performance. Herein, a novel N, P co-doped eave-like hierarchical porous carbon (NP-EHPC) for CDI is reported. To prepare the NP-EHPC, the core–shell ZIF-8@AF particles are first prepared through the kinetically-controlled growth of zeolitic imidazolate framework-8 (ZIF-8) and polymerization of p-aminophenol and formaldehyde (AF), followed by subsequent pyrolysis and post-doping with phosphorus. Owing to the unique eave-like morphology, presence of abundant mesopores, and co-doping of P and N, the NP-EHPC exhibits a high desalination capacity of 24.14 mg g−1 in 500 mg L−1 NaCl solution at 1.2 V and long cycling stability of over 150 cycles. Moreover, the density functional theory (DFT) calculation results reveal that the co-doping of N and P atoms can greatly enhance the binding energies for Na and Cl atoms and lead to superior electrosorption capacity. This work provides a new insight into the design of high-performance carbon materials for the desalination of brackish water.

In order to improve the mass transfer of anodic oxidation, an inverse opal-like marcoporous RuO2 electrode (IOMP-RuO2) was designed to enhance the concentration diffusion and molecule-to-electrode collision. Characterization methods including SEM, XRD, BET, LSV, CV, EIS and CA were performed to evaluate the properties of the IOMP-RuO2. In addition, the electro-oxidation capacity of the RuO2 electrode prepared at varying calcination temperature was also investigated. Results show that calcination temperature can affect the electro-oxidation performance of IOMP-RuO2 from the specific surface area, crystallinity of RuO2, voltammetric charge and impedance. Thereinto, crystallinity of RuO2 and impedance played decisive roles in the electrochemical oxidation. The fine crystallinity and lower impedance of IOMP-RuO2 acquired by 450 °C increased the electronic transport rate and allowed less redox couple to be involved in oxygen evolution, contributing to the best oxidation performance amongst others. Under this calcination temperature, the IOMP-RuO2 possesses larger electro-active areas, smaller electric resistance and enhanced mass transfer as compared to the planar RuO2 electrode. Furthermore, the IOMP-RuO2 gave a 42.7% higher degradation rate than that observed for the planar RuO2 electrode in the abatement of tricyclazole (TC) after 180 min. The high rate constant (2.14 × 10–2 min−1) and current efficiency (61.1%) achieved by IOMP-RuO2 contributed to a low energy consumption of 0.04744 kWh mg−1. Thus, these findings promoted the IOMP-RuO2 as an alternative electrode for wastewater decontamination.

The rational design of active and sustainable heterogeneous catalysts towards advanced oxidation process (AOPs) is of great significance for water remediation. Here, we synthesized Fe0/graphitized carbon composite catalysts for efficient removal of bisphenol A (BPA) by activating peroxymonosulfate (PMS). The Fe0/graphitized carbon composites were obtained by the pyrolysis of iron-tannic modified cotton, where tannic acid (TA) is an eco-friendly and low-cost polyphenol that can strongly form complexes with iron ions. The introduction of iron could significantly regulate the graphitization of carbon by changing the pyrolysis temperature. The combination of Fe0 and graphitized carbon can endow Fe-TCs with an enhanced adsorption ability due to strong complexation between Fe0 and BPA. The pyrolysis of iron-tannic modified cotton may serve as a novel strategy to design an efficient low-toxic metal-carbon catalyst for sulfate radical based processes in water remediation.

Water flooding in the microporous cathode is poisonous but inevitable for oxygen reduction reaction (ORR) in electro-Fenton (EF) processes. To meet this challenge, a facile modification was reported to stabilize performance of cathode through the infiltration process, which selecting superior CB-PTFE electrode as backbone and dimethyl silicon oil (DMS) as maturation layer. Characterized by FE-SEM, EDS, BET, XRD, the matured cathode was proved to be wrapped uniformly by DMS. Electrochemical performances of cathodes were evaluated by CA, CV, EIS and CP measurements in oxygen “starvation” condition. These results proved that the maturation layer improved the electrocatalysis on 2 e − ORR, the service lifetime from 1.68 h to 18.34 h, the working range of current density from 70 to 110 A m−2 and reduced the oxygen diffusion resistance from 74.23 to 8.07 Ω. Besides, H2O2 generation and oxygen utilization of 2%DMS cathode respectively reached 126.7 mg L−1 and 83.49% in 60 min, which were rarely influenced by pH and aeration rate even after water flooding process. 2%DMS layer served as the accelerated oxygen transport channel can explain the enhanced oxygen transport. The simulated contaminated solution containing a fungicide-flutriafol (FTF) was obtained 100% removal in about 40 min and 48.88% TOC removal in 2 h. The lifetime tests revealed much more stable decay of FTF under the broader operational condition.

This study introduces the application of the Fe(III)/flue gas desulfurization gypsum (FGDG) system to remove EDTA-chelated Pb(II). Systematic experiments were conducted to explore the possibility of removing EDTA-chelated Pb(II) and the crucial factors of the removal process, as well as to determine the underlying removal mechanism. The results showed that the removal reaction was a quick process, with the removal rate exceeding 90% after 1 min. The system removed 97.35% of EDTA-chelated Pb(II), reducing its concentration from 700 mg/L to 18.81 mg/L. EDTA-chelated Pb(II) can be most effectively removed at pH 2. This system had a high removal rate from 50 mg/L to 1000 mg/L of EDTA-chelated Pb(II), particularly at 700 mg/L when the removal rate reached 97.35%. When the molar ratio of Fe(III)/Pb(II) was greater or smaller than 1:1, an inhibitory effect on removal was observed. TOC and UV–Vis analyses indicated that ferric ions replaced lead ions, resulting in the conversion of the EDTA-chelated Pb(II) to EDTA-chelated Fe(III). Surface structure, crystalline phase and elemental distribution were analyzed to explore the transformation of substances. The results indicated that FGDG coprecipitated with free lead ions to form lead sulfate. Overall, the rapid and efficient removal performance with cost-effective characteristics makes the Fe(III)/FGDG system a potentially attractive method for the removal of EDTA-chelated Pb(II)in wastewater.

The discovery and development of a novel HER-2 tyrosine kinase inhibitor for the treatment of HER2-positive breast cancer are presented in this article. EGFR family has been recognized as a crucial meditator in the cancer progression; HER-2 tyrosine kinase was one of the members among them. In the effort to explore potent HER-2 inhibitors, a novel series of 4-anilino-3-cyanoquinoline derivatives have been designed, synthesized and evaluated. Most compounds possessed modest proliferation inhibition on SK-BR-3 cell line and HER-2 kinase. Compound 16 appeared to be the most potent compound (HER-2 kinase IC50: 19.4 nM, SK-BR-3 IC50: 94 nM). In the experiment of cellular cytotoxicity assay, compound 16 shows a much lower cytotoxicity than neratinib on Beas-2b cell line (Human bronchial epithelial cells). In conclusion, compound 16 would be a promising lead compound for further anti-breast cancer drug discovery.

The performance of thin film nanocomposite (TFN) membrane is significantly determined by the inherent structure and composition of the incorporated nanofillers. In this work, hydrophilic hollow nanocubes (HHNs) derived from zeolitic imidazolate framework 8 (ZIF-8) were incorporated into the polyamide layer via an interfacial polymerization approach. The HHNs with abundant hydroxyl groups on the surface were obtained by etching solid ZIF-8 using tannic acid. Benefiting from the hydrophilicity, hollow structure, and negative charge of HHNs, the outstanding nanofiltration performance of the composite membrane was achieved. With the assistance of HHNs, the permeance and Na2SO4 rejection of the TFN membrane increased up to 19.4 ± 0.6 L/(m2·h·bar) and 95.2 ± 1.4%, corresponding to an improvement of 190% of the permeance and 2.0% of the rejection compared to the pristine thin film composite membrane. Comparatively, the performance of TFN membranes prepared with solid ZIF-8 only shows 116% improvements of the permeance with slightly increased salt rejection. More importantly, the antifouling property of the TFN-4H membrane was also elevated. The flux recovery ratios of the TFN-4H membrane are 93.2 and 84.7% corresponding to humic acid and bovine serum albumin solutions, respectively. The results indicate that the nanofiltration performance of the composite membrane was significantly enhanced with the incorporation of HHNs.

A phenolic resin (PR)-assisted strategy to transform the zeolitic imidazolate framework (ZIF-67) into hierarchical Co/N-doped carbon rhombic dodecahedra for electrocatalysis is proposed for the first time. The hierarchical ZIF-67@PR composite carbon (HZPC) is obtained by coordinating the kinetic rate of precursors: nucleation/growth of ZIF-67 and polymerization of PR. The introduction of the PR polymer prevents agglomeration of cobalt nanoparticles, creates the well-distributed hierarchical porous structure and optimizes the composition. The advantages of the structure and composition endow HZPC with excellent oxygen reduction reaction (ORR) activity and long-term durability.

A polydopamine (PDA)-assisted interface-induction strategy is proposed to transform Zn, Co-zeolitic imidazolate frameworks (ZIFs) into hollow cactus-like carbon sheet/carbon nanotubes (CS/CNTs) for electrocatalysis for the first time. The precursor Zn, Co-ZIFs@PDA was obtained by the coordination between Co2+ (from ZIFs) and N atoms (from PDA). The introduction of PDA achieves simultaneous rational optimization of the composition (N-doping) and structure (2D/1D) by the interface-induction and confinement effect. The advantageous structure and composition endow CS/CNTs with outstanding oxygen reduction reaction activity and durability in alkaline solution.

Acceleration of Fe3+/Fe2+ cycle and simultaneous reduction of particle size with enhanced stability is extremely important for iron-based heterogeneous Fenton catalysts. In this work, Fe0-Fe2O3 composite nanoparticles embedded ordered mesoporous carbon hybrid materials (Fe0-Fe2O3/OMC) were rationally designed as efficient heterogeneous Fenton catalysts. Because of the confinement and reduction of OMC, highly dispersed Fe0-Fe2O3 active species with diameter of ∼8 nm were generated by an optimized carbothermic reduction process. In addition, Fe0-Fe2O3/OMC possesses ordered mesoporous structure with uniform mesopore, high surface area and pore volume. For comparison, two other catalysts, including solely Fe0 nanoparticles supported on ordered mesoporous carbon (Fe0/OMC) and solely Fe2O3 nanoparticles supported on ordered mesoporous carbon (Fe2O3/OMC) were also prepared. The Fenton catalytic performance of synthesized catalysts was evaluated by using H2O2 as oxidizing agent to degrade Acid Orange II (AOII). The results show that almost 98.1% of 100 mg L−1 AOII was removed by Fe0-Fe2O3/OMC in condition of neutral pH and nearly room temperature, which is much higher than those of compared catalysts. The enhanced catalytic activity of Fe0-Fe2O3/OMC for AOII removal is due to the efficient electron transfer between the Fe0 and iron oxide and the accelerated Fe3+/Fe2+ cycle. The stability and reusability of the catalyst was also investigated, which showed a good performance even after five consecutive runs. The as-synthesized catalyst is proved to be an attractive candidate in heterogeneous Fenton chemistry and practical application.

To enhance the antibacterial property and chlorine resistance, organic nanospheres, polypyrrole (PPy), were innovatively incorporated into the polyamide (PA) layer for fabricating thin film nanocomposite (TFN) membranes. Owing to the improved hydrophilicity and compatibility between the PPy nanospheres and the PA layer, the obtained TFN membranes exhibited significant water flux enhancement without sacrificing salt rejection. Under the optimal PPy dosage (0.006 wt%), TFN membranes showed a high water flux of 42.19 L/(m2 h), which was 118.0% higher than that of the pristine membrane. Remarkably, the chlorine resistance of TFN membranes was strengthened after the incorporation of PPy nanospheres, as evidenced by the less decreased salt rejection, as compared with the TFC and commercial RO membrane. In addition, the positively charged PPy nanospheres immobilized in the PA layer endow the TFN membranes with improved biocidal activity, which was much higher than that of the pristine membrane. This study shows that incorporating organic nanospheres into the PA layer is an effective strategy to develop new TFN membranes with enhanced performance for advanced water purification.

Enhanced biodegradation of high-strength pyridine was successfully achieved in the inner loop anoxic/oxic-dynamic membrane bioreactor (A/O-DMBR) in this study. Due to the key role of dynamic membrane in biomass retention, NH4+ released from pyridine biodegradation could be effectively nitrified to NO3− in oxic zone, which was then recirculated into the anoxic zone to serve as electron acceptor for pyridine biodegradation. Acetate dosage adversely affected pyridine biodegradation, due to the competitive effect of acetate towards NO3−. Increase of recirculation ratio positively affected pyridine biodegradation, due to high availability of NO3− at high recirculation ratio. At influent pyridine concentration as high as 1500 mg L−1, effluent turbidity was well maintained below 10 NTU, indicating excellent biomass retention performance of the dynamic membrane. Microbial community analysis confirmed the enrichment of specific functional species in both anoxic and oxic zones. Stable performance during 260 days’ operation confirmed the potential of A/O-DMBR for full-scale application.

In this study, bioaugmentation potential of 1H-1,2,4-triazole (TZ) degrading strain namely Shinella sp. NJUST26 and tricyclazole (TC) degrading strain namely Sphingomonas sp. NJUST37 was evaluated in a bench-scale activated sludge tank. The performance of the bioreactor demonstrated the feasibility of bioaugmentation by NJUST26 and NJUST37 in terms of almost complete TC and TZ removal, significant COD and TOC removal, as well as toxicity reduction. The effect of influent pH, hydraulic retention time (HRT) and triazole fungicide concentration was investigated in order to reach an optimal treatment performance. The bioaugmented process after the inoculation of NJUST26 and NJUST37 could maintain stable performance in terms of TZ, TC, COD and TOC removal from the wastewater. High-throughput sequencing analysis suggested that higher diversity and significant shifts in bacterial community structure were achieved after the inoculation of NJUST26 and NJUST37. However, both NJUST26 and NJUST37 lost their dominance during long-term operation, despite of the key role of the inoculation of NJUST26 and NJUST37 in the formation of effective microbial community.

A highly ordered three-dimensional macro-porous PbO2 (3D porous PbO2) electrode has been prepared for electrochemical oxidation of nitrogen-heterocyclic compounds. The 3D porous PbO2 electrode was fabricated by templated electrochemical deposition method with TiO2 nanotube arrays as substrate and SnO2-Sb as intermediate layer. The morphology and composition characterization of the 3D porous PbO2 electrode was performed by field emission scanning electron microscopy and X-ray diffraction, which revealed a uniform distribution of highly ordered macro-porous β-PbO2 structure. The Brunner−Emmet−Teller analysis suggested the electrode possessed large specific surface area of 37.39 m2·g−1. Electrochemical measurements indicated the electrode had a favourable oxygen evolution potential of 1.89 V and inner voltammetric charge of 14.48 mC·cm−2, which were higher than that of conventional PbO2 electrode. Furthermore, the electrochemical oxidation and TOC removal percentage of pyrrole, pyrazole and tetrazole obtained by 3D porous PbO2 electrode were 93.4%, 72.7%, 61.2% and 66.7%, 57.3%, 38.6% respectively, which were also superior to conventional PbO2 electrode. The intermediates were detected and analyzed by high-performance liquid chromatography, gas chromatography-mass spectrometer, and ion chromatography to propose a degradation pathway of pyrrole, pyrazole and tetrazole. Finally, quantum chemical calculation was introduced in this study by density function theory method, which is consistent with the experimental detection.

Porous matrix immobilization is considered as an effective approach to address the engineering challenges during practical application of nanoadsorbent. In this work, solid and hollow hydrous Zirconium (IV) oxide (ZrO2·nH2O, SHZO and HHZO) nanoparticles were enwrapped into millimeter-level beads by polyethersulfone through a mild liquid-liquid phase inversion technique. The beads possess asymmetric and hierarchical structure with an exterior porous surface dense layer and numerous inner interpenetrating finger-like channels, which promote the transportation of molecule and prevent the leaching of nanoadsorbents. As compared to SHZO beads, HHZO beads exhibited higher efficient adsorption capacity toward Pb (II) (104 mg·g−1), which could remain at 94% of HHZO nanoparticles. The effects of pH, the stability of adsorbents and coexisting ionic are further explored in detail. The Pb (II) removal mechanism is further studied by the EDS mapping, XPS, FTIR measurements, further indicating the surface hydroxyl groups played a key role in the adsorption process. Fixed-bed column sorption experiment and in situ regeneration were conducted so as to examine the practical application of the beads. Therefore, this kind of beads indicated the potential practical application in industrial wastewater treatment.

MXene, as an emerging group of two-dimensional layered material, attracted more and more attention due to its extraordinary physical properties. In this study, a sandwich-like Co3O4/MXene (CMs) composite was prepared via a one-step heating method and used as a novel catalyst to activate peroxymonosulfate (PMS) for Bisphenol A (BPA) degradation. The sample (CM-20%) achieved an efficient catalytic activity with 95% removal of BPA at 20 mg/L within 7 min. Meanwhile, the parameters in the degradation process were optimized. In particular, CM-20% obtained excellent BPA removal efficiency in a wide pH range (4–10). Anions like NO3− and Cl− had a slight negative effect while HCO3− had a great negative effect on catalytic activity in CM-20%/PMS system. Notably, the catalyst exhibited a good performance after 5 consecutive runs and the leached cobalt ion was negligible. Electron paramagnetic resonance (EPR) analysis and quenching tests identified SO4 − and OH were the reactive species. The pathway of degradation was also detected by analyzing its intermediates using LC-MS. This work provides a new field of MXene composite material for PMS remediation of organic pollutant and widens the application of MXene in environmental remediation field.

The application of bioelectrochemical system (BES) for recalcitrant contaminant removal is a promising strategy for wastewater treatment but is limited to the low cathodic reduction efficiency. In this paper, a new approach using polypyrrole as nitrogen source has been utilized for the fabrication of nitrogen-doping graphene (NG) modified graphite felt (GF) electrodes. The results of the Raman spectrum and X-ray photoelectron spectroscopy confirmed that the nitrogen species, i.e., pyridinic N, pyrrolic N and graphitic N, in the NG sheets could be conveniently controlled by tuning the pyrolysis temperature from 300 to 600 °C during carbonization process. Cyclic voltammetry and electrochemical impedance spectra measurements verified that the catalytic activity and electron transfer efficiency of the ‘as prepared’ electrodes were greatly improved. Due to the synergistic effect of pyrrolic N and graphitic N, the 4-nitrophenol reduction efficiency of the modified cathode increased 2.1 times higher than that of blank GF cathode in the BES system.

In this study, a pyridine-degrading strain namely NJUST30 was isolated from aerobic granules capable of degrading pyridine and was identified as Paracoccus sp. At incubation temperature of 30 °C, initial pH of 7.0 and initial pyridine concentration of 500 mg L−1, complete pyridine removal could be achieved within incubation period as short as 54 h. Pyridine biodegradation profile by NJUST30 could be well fitted by the first-order decay kinetic model, suggesting the recalcitrant nature of pyridine and the inhibitory effect of pyridine towards NJUST30. Major intermediates during pyridine biodegradation by NJUST30, including 2,4-dihydroxy-2H-pyridine-3-one, 2-carbonyl-succinic acid, 1,2-dihydro-pyridin-2-ol, piperidin-2-ol and 4-formylamino-butyric acid were identified through HPLC/MS. Based on these intermediates, a distinct pyridine biodegradation pathway via hydroxylation, pyridine ring cleavage, carbonylation and carboxylation was revealed for the first time.

Simultaneous removal of multi-component pollutants from atmosphere is crucial for personal protection. Herein, porous carbon spheres (PCSs) with 1.2 mm diameter were prepared through the phase inversion route followed by carbonization using g-C3N4 and PVDF as precursors. The structure and chemical property of PCSs can be tailored via controlling the content of g-C3N4 due to its dual-function of template and nitrogen source. The resultant PCSs possess high surface areas, rich nitrogen content and favorable micro/meso/macro hierarchical porous structure, which are highly desired for simultaneous removal of benzene and H2S. The dynamic adsorption behaviors for benzene and H2S were investigated to examine the protective performance. Owing to the abundant porous structure and chemical polarity, PCSs extend the protective performance for H2S under retention of adsorption performance for benzene. The promotion on adsorption performance for H2S from mixture could be attributed to the change of electron distribution on nitrogen atom caused by the adsorbed benzene. The adsorption kinetic confirmed the enhancement on mass transfer ascribed to meso/macro hierarchical porous structure. These results revel that PCSs would be a promising adsorbent in personal protective equipment for VOCs and TICs.

Developing novel coating materials for fast and sensitive solid-phase microextraction (SPME) is highly desired but few are achieved. In this work, a new material of metal-organic framework (MOF)-derived hollow carbon nanocubes (HCNCs) was prepared as a fiber coating material for SPME. The HCNC-coated fiber (denoted as HCNCs-F) exhibited a better enrichment performance than solid carbon nanocube (SCNC)-coated fiber (denoted as SCNCs-F) and commercial fibers based on the abundant active sites of the hollow structure, hydrophobic interactions, and π-π interactions. Moreover, because of the reduced mass-transport lengths of the hollow mesoporous structure, the HCNCs-F demonstrated a faster mass transfer compared with the SCNCs-F. The HCNCs-F was used to determine the six hydrophobic polycyclic aromatic hydrocarbons (PAHs) with wide linear ranges (10-2000 ng L-1 for naphthalene and 5-2000 ng L-1 for the other five analytes), good reproducibility (relative standard deviation < 8.8%), and low detection limits (0.03-0.70 ng L-1). Finally, the HCNCs-F was successfully applied for the determination of PAHs from the real water samples. It can be concluded from the results that MOF-derived hollow carbon materials are promising candidates for the fast SPME and can be used for practical applications in analytical chemistry.

The electrode material with high electrosorption capacity and fast electrosorption rate is highly desired in capacitive deionization (CDI) process. To meet this demand, the nitrogen-doped cluster-like porous carbons (NCPCs) with hierarchical hollow nanoarchitecture were rationally prepared by carbonizing the polydopamine/nano-ZnO composite and employed as CDI electrodes. The resultant NCPCs possess an interconnected hierarchical structure with a hollow cavity, nitrogen-doping property, high specific surface, large pore volume and good wettability. All these merits can ensure a huge accessible electrosorption interface for the very quick diffusion of ions so that achieve an excellent CDI performance. Particularly, the sample carbonized at 900 °C (NCPC-900) with the optimal porous structure and chemistry composition exhibits the highest electrosorption capacity of 11.98 mg g− 1 in 100 mg L− 1 NaCl solution. Besides, the NCPC-900 electrode shows a good cycle stability over 20 electrosorption-desorption cycles. These results render that the NCPCs have the great potential as the electrode material for high performance CDI desalination.

A series of novel blend ultrafiltration (UF) membranes have been successfully prepared from commercial poly (ether sulfone), lab-synthesized sulfonated poly (aryl ether sulfone) (SPAES, 1 wt%) and copper nanoparticles (0 ∼ 0.4 wt%) via immersion precipitation phase conversion. The micro-structure and separation performance of the membranes were characterized by field emission scanning electron microscopy (SEM) and cross-flow filtration experiments, respectively. Sodium alginate, bovine serum albumin and humic acid were chosen as model organic foulants to investigate the antifouling properties, while E. coil was used to evaluate the antibacterial property of the fabricated membranes. By the incorporation with SPAES and copper nanoparticles, the hydrophilicity, antifouling and antibacterial properties of the modified UF membranes have been profoundly improved. At a copper nanoparticles content of 0.4 wt%, the PES/SPAES/nCu(0.4) membrane exhibited a high pure water flux of 193.0 kg/m2 h, reaching the smallest contact angle of 52°, highest flux recovery ratio of 79% and largest antibacterial rate of 78.9%. Furthermore, the stability of copper nanoparticles inside the membrane matrix was also considerably enhanced, the copper nanoparticles were less than 0.08 mg/L in the effluent during the whole operation.

Arsenic-contaminated water has significant adverse impacts on human health and ecosystems. We developed a new adsorptive membrane by modifying the porous support layer of a phase inversion formed membrane for arsenic removal. Iron oxide (Fe3O4) microspheres were immobilized in the support layer of the membrane by reverse filtration, followed by dopamine polymerization. The prepared adsorptive membrane was compared with a virgin membrane without Fe3O4 microspheres and a Fe3O4 blended membrane in terms of membrane structures and separation performance. The adsorptive membrane prepared by our new method had comparable water permeability and rejection performance with the virgin membrane without Fe3O4 microspheres, but higher rejection performance and dynamic adsorption capacity than the membrane prepared by the conventional blending method. Both static and dynamic adsorption modes were used to evaluate the adsorption performance of the membranes. Our new adsorptive membrane also had excellent regeneration performance. After three regeneration cycles, the membrane was still capable of treating more than 2 tons of As-contaminated water/m2. The adsorptive membrane of 1 m2 could treat over 7 tons of water to the drinking water standard in terms of arsenic concentration during three regeneration cycles. Therefore, our adsorptive membrane may pave a new way for arsenic removal from water and ensuring drinking water security.

In this work, we have fabricated a kind of N-doped hierarchal carbon fiber web by electrospinning hollow mesoporous carbon spheres (HMCSs) into fibrous structure. The as-synthesized carbon fiber web with novel mulberry-like morphology, thus denoted as MC-FW, possesses micro/meso/macroporous porosity, large surface area, high conductivity and multi-level structure, which are highly desired for supercapacitor electrode materials. The electrochemical measurements demonstrate that the designed MC-FW shows high capacitance (298.6 F g−1), favorable capacitance retention (71.0%) and long cycle life (97.3% capacitance retention after 5000 cycles). Notably, the capacitance of 298.6 F g−1 for MC-FW is higher than the capacitance reported so far for many hollow carbon spheres and carbon fibers, which may contribute to the synergistic effect between the merits of HMCSs (e.g. micro/meso/macroporous hierarchal structure, large surface area, high pore volume) and advantages of 1D carbon fiber (e.g. large aspect ratio and high conductivity). It is believed that this distinctive carbon fiber web may show promising prospects as advanced energy storage materials and catalyst.

Flue gas desulphurization (FGD) gypsum is an abundant waste generated from coal-fired power plants. This study evaluated the potential application of hydroxyapatite (F-HAP) derived from FGD gypsum for immobilization of lead (Pb) and copper (Cu) in water and soil. MINTEQ software was employed to determine the species distribution of Pb(II) and Cu(II) at different solution pH conditions. The factors that affect sorption behavior such as pH effect, sorption kinetics, thermodynamics, and isotherms were investigated using batch tests. Various kinetics and isotherms models were used to fit the obtained data. The experimental results showed that the amount of Pb(II) and Cu(II) adsorbed on F-HAP increased as the pH increased from 2.0 to 6.0, and adsorption was enhanced with the rise in temperature. The predicted maximum adsorption capacities were found to be 1.376 and 0.460. mmol/g for Pb(II) and Cu(II), respectively. The values of mean free energy (E) obtained from Dubinin-Radushkevich (D-R) model implied that the chemical reaction, which was stronger than ion exchange governed the process of Pb(II) adsorption, while the adsorption of Cu(II) was mainly ascribed to ion exchange. XRD analysis revealed that the final solid obtained after Pb(II) immobilization was mainly mixed of pyromorphite and F-HAP, while the final solid acquired after Cu(II) immobilization still consisted of a single phase of F-HAP. On the other hand, application of F-HAP in contaminated soil effectively reduced the leachable and exchangeable Pb and Cu, reflecting that F-HAP is a potential material for remediating environmental pollution with Pb and Cu. This study realized the potential of a modified geochemical waste material towards remediation of metal contaminated soils, providing very useful and valuable information for other similar solid wastes, such as paper sludge and phosphogypsum. Refereed/Peer-reviewed

The facile synthesis and engineering of highly active catalysts is an urgent requirement for the practical application of environmental remediation. In this report, we demonstrate the convenient synthesis of Co3O4-incorporated carbon composite (Co3O4/CC) by pyrolysis of a cobalt complex modified cotton cloth, which can be extended to other cellulose products (cotton, filter paper). Benefitting from the ultrafine Co3O4 particles with a mean particle size of ∼7.4 nm, the Co3O4/CC catalyst exhibits excellent performance for biphenol A (BPA) removal based on the sulfate radical (SO4˙−) process. Notably, as a proof-of-concept application, the Co3O4/CC packed column as a microreactor was designed and used in the continuous-flow reaction. Leveraging on the long half-life time period and high oxidability of SO4˙−, the degradation rate of BPA could increase above 95% at a flow rate of 2 mL min−1 when the total BPA solution reached to 1400 mL. The convenient synthesis of a high-performance catalyst and its efficient application to a continuous-flow reaction represent a further step towards practical application of SO4˙− based advanced oxidation processes.

In this work, Fe3O4@C yolk-shell carbon architecture were fabricated in one pot sol-gel process and further examined as adsorbents for the removal of sulfamethazine. To understand yolk-shell structure on the adsorption properties of sulfamethazine, another adsorbent without hollow cavity, i.e., Fe3O4@SiO2@C carbon material, was also prepared for comparison. The adsorption results showed the yolk-shell carbon materials complied with the pseudo-second order kinetics model. Based on the Langmuir model the yolk shell material possess a Qmax of 312 mg g−1, which is higher than that of core-shell materials (236 mg g−1). Due to the magnetic property, the yolk-shell carbon materials can be retrieved facilely from the aqueous media by an external magnet and 89.1% of recovery can be achieved over five adsorption desorption cycles. Possessing high surface area, a well-defined interface of the material and central cavity the as-prepared material has proved to be a potentially eminent adsorbent for the broad scale removal of sulfamethazine from industrial processes.

The simultaneous rational optimization of structure and composition is extremely important for improving the catalytic performance of yolk–shell nanoreactors, but has been rarely achieved so far. In this work, yolk–shell Co3O4/C@SiO2 nanoreactors (YSCCSs) are facilely synthesized by coordinating the growth of Co-zeolitic imidazole framework (ZIF-67) crystals with the hydrolysis/condensation of tetraethoxysilane (TEOS). In this process, the preliminarily formed ZIF-67 crystals play an essential role in the final structure of YSCCSs, which can be used as the template for silicon hydroxide growth and the precursors for carbon and cobalt species. To present the advantages of YSCCSs as a catalyst, sulfate-radical-based advanced oxidation processes (SR-AOPs) for bisphenol A (BPA) degradation were chosen as the model reaction. For comparison, three other catalysts, including yolk–shell Co3O4@SiO2 nanoreactors (YSCSs), and Co3O4 and ZIF-67 derived Co3O4/C nanoparticles, were also tested. The results show that YSCCSs exhibit significant BPA degradation performance over YSCSs, and CO3O4 and Co3O4/C nanoparticles. This outstanding catalytic performance is ascribed to the rational optimization of the catalyst from the following two aspects: (i) confinement effect of yolk–shell nanostructure and the improved dispersity of carbon supported Co3O4 species enhance the catalytic activity and stability (structure optimization); and (ii) the existence of graphitized carbon accelerates the electron transport from the catalyst to peroxymonosulfate (PMS) and thus increases the reaction kinetics (composition optimization). The results of this research show that metal–organic framework (MOF)-derived nanoreactors with a rational structure and composition have a promising application prospect for environmental remediation.

A novel single-step approach, named phase transformation interfacial growth (PTIG), was developed for the fabrication of metal-organic framework membranes on polymeric substrates. Both the separation layer and the substrate were formed within the PTIG process. This innovative methodology paves a way for fabricating high-quality MOF membranes.

During the boronic acid production process, boronic acid emission causes considerable loss of resources and water pollution. At present, adsorption is the preferred technology to treat boron pollution. Although conventional adsorbents are simple and effective, their regeneration and recovery are challenging, which hinder their wide-scale application. Considerable research efforts have been devoted to resolving the two issues mentioned above. Herein, a novel boron-adsorbing magnetic material with a cis-diol structure possessing boronate affinity was prepared. 3-Hydroxytyramine hydrochloride auto-polymerization (PDA), magnetic graphene oxide (GO) synthesis, polyethylenimine (PEI) self-assembly, and a 3,4-dihydroxyphenylpropionic acid (DHHA) covalent bonding procedure were conducted to synthesize a Fe3O4/PDA/GO/PEI/DHHA nanocomposite. This nanocomposite exhibited excellent adsorption performance and was easily recycled using an external magnetic force. The boronic acid was separated and recovered by simply adjusting the pH of the solution. The nanocomposite’s adsorption capacity reached 91.46 mg g-1 at 30 °C with 4-formylphenylboronic acid (FPBA) as a model compound. Besides, the adsorption capacity of the nanocomposite was maintained at >89% of its original value even after five cycles. It was confirmed that the adsorption was primarily a thermochemical reaction controlled by entropy change. Thus, this novel adsorbent can be used for boron removal because it exhibits significant boronate affinity and high regeneration ability and is easy to recycle.

Purification of various types of industrial wastewater containing chelated heavy metals (CHMs) remains a challenging task due to the easy dissolution, poor biodegradation and extremely high stability over a wide pH range. Compared with the common CHMs, the attention of Cr(III) complexes is greatly insufficient. Especially, Cr(III) of the wastewater is easily reoxidized and converted into Cr(VI) with high biotoxicity during the transferring process, so the treatment of Cr(III) complexes needs to be treated more strictly. Obviously, compared with previous advanced oxidation and replacement-coprecipitation technologies, adsorption method could directly remove Cr(III) complexes in one step, thus avoiding the accumulation of secondary toxic Cr(VI). Considering that ferrihydrite (Fh) materials are widely distributed on the nature, excellent adsorption performance, low cost, and environmentally friendly, this paper proposes a novel strategy that uses the common Fh as an efficient adsorbent to realize one-step elimination of typical EDTA-Cr(III) complexes without introducing secondary pollution. Batch experiment results illustrated that more than 93% of EDTA-Cr(III) was removed at pH = 3 or 6 (a final concentration of

A novel electrochemical filter has been prepared for the effective adsorption and electrochemical oxidation of aqueous organic pollutants. The adsorptive electrode utilized in the electrochemical filter was a porous Graphite-RuO 2 electrode decorated with multi-walled carbon nanotubes (MWCNTs) adsorption layer, which was prepared by sol–gel coating, thermal decomposition, and vacuum filtration synthesis. The morphology and composition of adsorptive electrode characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) revealed a uniform distribution of RuO 2 active coating and MWCNTs adsorption layer. Electrochemical measurements indicated that the adsorptive electrode possessed a favorable oxygen evolution potential (OEP) of 1.42 V and inner voltammetric charge 170.05 mC·cm −2 , which were higher than that of non-MWCNTs electrode. Furthermore, the mass transfer of adsorptive electrode was enhanced as high as 4.6-fold in the electrochemical filter. The optimal operation parameters obtained was 3 mA·cm −2 and 7 g·L −1 Na 2 SO 4 . Under this condition, the electrochemical filter can remove > 97% of pyrrole and >75% of total organic carbon. The pyrrole oxidation mechanism of electrochemical filter was also investigated, revealed three dominant reaction stages: adsorption (≤0.3 V), direct oxidation (0.3–1.2 V) and indirect oxidation (>1.2 V). In general, the high electrochemical performance of Graphite-RuO 2 -MWCNTs filter on pyrrole removal resulted from the enhanced mass transfer, which attributed to the synergistic effect of adsorption from MWCNTs, electrochemical oxidation and convection by filtration.

Metal-organic framework (MOF) nanocrystalline materials have received great attention because of their application in heterogeneous catalysis. However, they suffer from poor separation from reaction mixtures in practical applications. In this study, we report the first cobalt metal-organic framework containing zeolitic imidazolate framework (ZIF)-67 nanoparticles immobilized on electrospun polyacrylonitrile (PAN) nanofibers, which was used as a composite catalyst (ZIF-67/PAN) for activating peroxymonosulfate (PMS). Detailed characterization showed that the ZIF-67/PAN nanofibers possessed a flexible one-dimensional structure. To demonstrate the catalytic performance of the ZIF-67/PAN nanofibers, the activation of PMS for the catalytic degradation of acid yellow-17 (AY) was chosen as the model catalytic reaction. The results show that 95.1% of AY (500 mg L−1) was removed by ZIF-67/PAN in 10 min, which is much higher than many other PMS catalyst. More interestingly, the flexible ZIF-67/PAN composite nanofibers catalysts were not only easy to separate from solution but they also retained high catalytic stability. The influencing factors for PMS activation were also investigated, including the catalyst dosage, reaction temperature, solution pH, and doping with competing organic molecules. The degradation mechanism was elucidated by electron paramagnetic resonance experiments. This work provides a new sight into the fabrication of high-performance MOF catalysts with outstanding recycling properties, which may promote the use of MOF materials in more practical applications.

Ordered mesoporous silica (OMS) film supported on anodized titanium wire was fabricated as a new solid phase microextraction (SPME) fiber for the extraction of chlorophenols (CPs) from aqueous media followed by the determination with gas chromatography flame ionization detection (GC-FID). The supported OMS film was prepared via a solvent evaporation-induced self-assembly approach (EISA) combined with dip-coating technology. Commonly used fragile fused silica fiber was replaced by anodized titanium wire. The coating materials were characterized by N2 adsorption-desorption, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and thermogravimetric (TG) analysis. The N2 adsorption-desorption results show the OMS material has well-ordered mesostructure with uniform pore diameter. The SEM images verify that the OMS film was successfully grafted onto the surface of anodized titanium wire. The resultant method based on the OMS fiber exhibited wide linear ranges (0.2-200μgL-1), low detection limits (0.03-0.12μgL-1) and good repeatabilities (6.2-9.8% for one fiber, 8.9-13.2% for fiber-to-fiber). No significant change was observed after being subjected into high temperature or immersed in organic solvents. The new fiber was successfully applied to the extraction and determination of three CPs compounds in the natural water samples. Thus, the OMS fiber is a promising alternative to the commercial fiber as it is easily and inexpensively prepared with high extraction capacity and good stability.

In this work, nitrogen doped hollow carbon spheres (NHCS) were synthesized via modified “silica-assistant” route and further examined as adsorbents for the removal of benzene, which is a typical volatile organic compounds (VOCs). To understand the structure and composition on benzene removal, solid carbon spheres (SCS), nitrogen doped solid carbon spheres (NSCS) and hollow carbon spheres (HCS), were also prepared for comparison. The structure and morphology characterization revealed that the resultant carbon spheres possess uniform spherical shape, abundant micropores and mesopores with solid or hollow structure and high pore volume. Combined with Raman and XPS spectra, the composition of carbon spheres was successfully tailored via introduction of nitrogen atom into carbon matrix. To present the removal performance of carbon spheres for VOCs, the dynamic adsorption behavior was evaluated. Attributed to the combined effect of hollow structure and nitrogen doping, NHCS presents remarkable dynamic adsorption performance for benzene vapor with adsorption capacity of 766 mg/g. The enhancement on desorption behaviors resulting from hollow structure of HCS is confirmed when compared with SCS. Carbon spheres exhibit good regenerability based on desorption experiment. The mechanism of enhanced adsorption performance caused by nitrogen doping is clarified as the combined action of adjustment on porous structure and composition. These results indicate that NHCS would become a promising candidate for VOCs removal.

In order to develop an electrochemical technology with low-energy consumption for water treatment applications, we fabricated a novel reactive electrochemical membrane (REM) operated in cross-flow filtration mode. The REM with three-dimensional ordered macroporous PbO2 (3DEM-PbO2) film was synthesized via templated deposition that was based on a porous Ti substrate. Compared to conventional flat Ti/PbO2 (F-Ti/PbO2) electrode, the 3DEM-PbO2 possessed larger specific surface area (38.89 m2 g−1), higher oxygen evolution potential (OEP, 1.9 V), larger Voltammetric charge (238 mC cm−2) and smaller electron transfer resistance (1.43 Ω). Furthermore, advection-enhanced mass transfer was obtained when the 3DEM-PbO2 REM is operated in an electrochemical filtration reactor (EFR), relative to a traditional batch reactor (BR). The electrochemical mineralization experiments with flutriafol (FTF) demonstrated that the 3DEM-PbO2 REM operated in the EFR was active for FTF and TOC removal at a low current density of 5 mA cm−2. The oxidation current efficiency of REM operated in a EFR was much higher than that of conventional electrochemical system, and the corresponding energy consumption was lower (0.0505 kWh g−1 FTF, at FTF removal of 75%). The hydroxyl radicals (·OH) production and its utilization rate of the REM was significantly improved, resulting from a combination of the strong catalytic activity of 3DEM-PbO2 and the enhanced mass transfer by filtration mode. Furthermore, computational fluid dynamics (CFD) method was carried out to help explain the improvement of oxidation performance with 3DEM-PbO2 REM in a EFR. Eventually, the electrocatalysis experiments of practical wastewater demonstrated the extreme promise of 3DEM-PbO2 REM for tailwater advanced treatment applications.

In this study, a novel hollow mesoporous carbon spheres-based fiber (HMCSs-F) was fabricated to immobilize HMCSs onto a stainless steel wire for solid-phase microextraction (SPME). Characterization results showed that the HMCSs-F possessed a large specific surface area, high porosity and uniform pore size. To demonstrate the extraction performance, a series of polycyclic aromatic hydrocarbons (PAHs) was chosen as target analytes. The experimental parameters including extraction and desorption conditions were optimized. Compared to commercial fibers, the HMCSs-F exhibited better extraction efficiency for PAHs. More interestingly, a good extraction selectivity for PAHs from the complex matrix was observed in these HMCSs-F. The enhanced SPME performance was attributed to the unique pore structure and special surface properties of the HMCSs. Furthermore, under the optimum conditions, the limits of detection (LODs) for the HMCSs-F were in the range of 0.20-1.15ngL-1 with a corresponding relative standard deviation that was below 8.6%. The method was successfully applied for the analysis of PAHs in actual environmental water samples with recoveries ranging from 85.9% to 112.2%. These results imply that the novel HMCSs-F have potential application in environmental water analysis.

Pesticide tailwater often contains residual and toxic contaminants of triazole fungicides (TFs) due to their poor biodegradability which will do great harm to local aquatic systems. For this case, a novel electrochemical reactor (TPER) equipped a tubular porous RuO 2 -Sb 2 O 5 -SnO 2 electrode was assembled and then employed to deeply treat pesticide tailwater. Characterizations of the electrode studied by SEM, EDS and XRD analysis indicated that it owns a porous structure and a compact and crack-free surface. Influence of the porous structure on electrochemical property was examined by cyclic voltammetry and normal pulse voltammetry. The results indicated that porous structure can not only enlarge electrochemical active area but also increase mass transfer efficiency by 5.7-fold in flow-through mode compared with batch mode. Furthermore, the optimal operating conditions of TPER were flow rate of 250 mL min −1 and current density of 4 mA cm −2 . After 1.5 h treatment under these conditions, Tz, TC and PPC were removed by 98.9%, 99.0% and 98.4% respectively, while 81.9% of COD was also removed. Additionally, the microbial content was dropped to 0 CFU mL −1 and fecal coliform was lower than 2 MPN (100 mL) −1 . All results demonstrated that the treated tailwater has met the Class 1 of National Discharge Standard of China. Especially, operating cost of TPER was only $ 0.33 per ton. The excellent performance together with the low cost indicated that TPER is a promising option for depth treatment of industrial tailwater.

To enhance the structure stability of conventional capacitive deionization (CDI) electrode, this work intends to provide a facile preparation of Titania nanotubes (TiO2-NTs) based electrode with carbon imbedded for capacitive deionization application. The TiO2-NTs array is obtained through anode oxidation method on the titanium substrate, then carbon precursors were induced into the nanochannels of TiO2-NTs carrier by the vacuum pressure and transferred to carbon capacitor through anaerobic pyrolysis process. Such structure possesses a unique combination with hollow carbon fibers as layer binders to fix the upper carbon spheres onto TiO2-NTs substrate. The as-prepared electrode revealed an excellent mechanical stability, electrosorption ability and electroconductibility as well as a favorable hydrophilicity especially after acid modification. This paper also investigates the influence of various operational parameters on the capacitive deionization process, including feed temperatures, flow rates and initial salt concentrations. The electrosorption kinetics is also analyzed within the deionization process, which shows the novel electrode presents a better sorption rate as well as a higher sorption capacity of 13.11 ± 0.58 mg/g at 1.2 V and 500 mg/L feed concentration. Furthermore, the removal principles of CDI electrode under multi-ion circumstance are compared and discussed depending on existing studies.

We report the first preliminary and extensive study on the solution self-assembly behaviors of poly(vinylidene fluoride)–b-polystyrene (PVDF–PS) block copolymers. The two PVDF–PS polymers we examined have the same length of PVDF block with number averaged repeating unit of 180, but distinctly different lengths of PS block with number averaged repeating unit of 125 and 1202. The self-assembly experiments were carried out in a series of mixture solutions containing a good solvent N,N-dimethylformamide and a selective solvent with different ratios. Our results showed that the self-assembly process was greatly affected by the two factors we examined, i.e. the length of the PS block and the solvent composition. We hope that our study could stimulate more research on the self-assembly of PVDF-containing polymers in solution. Keywords: Self-assembly, Block copolymers, Poly(vinylidene fluoride)

In order to develop a highly efficient anode material for recalcitrant phenol degradation in bioelectrochemical system (BES), fabrication of polypyrrole (PPy)/β-MnO2 composite onto graphite felt (GF) electrode through facile one-step electrodeposition was investigated in this study. The successful coating of PPy/β-MnO2 onto GF surface was verified by scanning electron microscopy, Raman spectrum and XPS. The improved electrochemical property of the GF electrode modified by PPy/β-MnO2 was confirmed by cyclic voltammetry analysis, chronoamperometric and electrochemical impedance spectra. The application of PPy/β-MnO2 modified GF electrodes in BES notarized the superior degradation performance towards phenol. Shorter startup time, higher mineralization efficiency and improved bacteria adhesion was achieved in BES using PPy/β-MnO2 modified GF as anode. Coulombic efficiencies of 17.3 ± 0.5% in BES using PPy/β-MnO2 modified GF as anode was much higher than those in BES using PPy modified GF and blank GF as anode, which were as low as 12.1 ± 2.4% and 6.6 ± 1.3%, respectively. The key role of MnO2 and possible degradation pathway involved in phenol degradation was further proposed. The milder fabrication condition, improved electrochemical activity and increased phenol degradation efficiency suggest that PPy/β-MnO2/GF has a promising future in BES application for recalcitrant phenol catalytic degradation.

Iron-copper bimetallic nanoparticles supported on carbon nanofibers as a composite catalyst (FeCu/CNF) was prepared for the first time in this work. The iron-copper bimetallic nanoparticles were formed in situ by carbothermic reduction during the carbonization process. The characterization results show that the FeCu/CNF possesses fibrous morphology, porous structure with high specific surface area, and dispersed iron-copper nanoparticles. For comparison, three other catalysts, including solely iron nanoparticles supported on carbon nanofibers (Fe/CNF), solely copper nanoparticles supported on carbon nanofibers (Cu/CNF) and iron-copper nanoparticles supported on blocky carbon matrixes (FeCu/C) were also prepared. The heterogeneous Fenton catalytic performance of synthesized catalyst was evaluated by degradating a typical azo dye, Acid Orange II (AOII). The results show that almost 97.7% of 100 mg/L AOII is removed by FeCu/CNF in reaction time of 1 h, which is much higher than those of comparison catalysts operated in the same experimental condition. Additionally, the FeCu/CNF also reveals a wider pH adaptation ability compared with Fe/CNF. Based on the results of OH detection and resistance of mass transfer testing in catalysts, the remarkable catalytic performance of FeCu/CNF is considered as the synergistic effect of iron and copper and the superiority of nanofibrous structure in catalyst. The good stability and recoverability of FeCu/CNF were also demonstrated. The as-synthesized catalyst is proved to be an attractive candidate in heterogeneous Fenton chemistry.

A new catalyst system of CoP/peroxymonosulfate (PMS) is presented, which achieved significant improvement in catalytic activity. Nanostructured CoP, obtained by a simple solid-state reaction, exhibited dramatic catalytic activity with 97.2% degradation of orange II of 100ppm within 4min. Moreover, the high efficiency could be reached for other phenolic pollutants, i.e., phenol and 4-chlorophenol. The reaction rate is much higher than the most reported catalysts. Effect of parameters on catalytic activity of the catalyst was studied in detail. Notably, initial pH of the solution had a slight negative effect on the catalytic performance over the pH range 4.07-10.92, suggesting that CoP has the great adaptability of pH. CoP/PMS demonstrated excellent anti-interference performance toward anions (Cl-, NO3-, and HCO3-). In addition, the pathway of degradation of orange II is proposed by analyzing its intermediates. Based on the XPS spectra of CoP, the identification of the reactive species (OH and SO4-) by electron paramagnetic resonance (EPR) analysis and quenching tests, a possible mechanism for activation of PMS by CoP was proposed. Considering the dramatic catalytic activity, a wide range of pH catalyst suited, CoP is believed to provide robust support for the promising industrial application of AOPs.

Capacitive deionization (CDI) with high energy efficiency, low cost, and non-secondary pollution is considered an emerging desalination technology. To pursue excellent electrode materials with high electrosorption capacity is highly desired for practical CDI application. In this work, the protic salt-derived porous carbon was synthesized via the direct pyrolysis of the protic salt, i.e., p-phenylenediamine bisulfate ([pPDA][2HSO4]), which was obtained by simply neutralizing p-phenylenediamine with sulfuric acid. The resultant carbon materials possessed large specific surface area, high nitrogen doping, good graphitization and large mesopores. These intrinsic characteristics endowed protic salt-derived porous carbon with excellent electrochemical properties and CDI desalination performance. Particularly, the carbon obtained at 900 °C (C-9) with optimal porous structure (1082 m2 g−1) and chemical composition (5.2% N) exhibited the best electrochemical property with a specific capacitance of 222.3 F g−1. The CDI results showed that C-9 had a high electrosorption capacity of 16.5 mg g−1 in 100 mg L−1 NaCl solution and excellent electrosorption stability over 20 times of adsorption-desorption cycles. Furthermore, we demonstrated the dependence of CDI performance on the balance between porous structure and chemical composition. These results imply that the protic salt-derived porous carbon should be a promising electrode material for CDI application.

In this work, a novel integrated system in pilot plant scale of electrochemical oxidation, upflow biological aerated filter and electrodialysis was investigated for high level standard reuse of triazole fungicides discharged water. In order to enhance biodegradable property of discharged water to be easier to recycled, a novel enhanced electrochemical oxidation reactor was designed and applied as pretreatment process. Effects of operating parameters on the performance of each process were studied with the discussion of economic evaluation. The results indicated that the optimal condition was current density of 5 mA/cm 2 , flow velocity of 3 m 3 /h, pH value of 5.0 and without supporting electrolyte. The target species including N-heterocyclic contaminants (tricyclazole, 1H-1,2,4-triazole and propiconazole) were removed over 90% from the discharged water by this process. Within upflow biological aerated filter, the remained COD would decrease further to the level less than 60 mg/L from 250 mg/L. Then the salt was removed efficiently during electrodialysis. Final effluent revealed a very low level of COD of 58.32 mg/L, TOC of 20.56 mg/L, EC 50,48h of 73.1 ± 2.1%, consistent with an excellent removal of the target species of 94.19% tricyclazole, 90.11% 1H-1,2,4-triazole and 100% propiconazole, >99% salt and a low operating cost of $0.85. The excellent performance as well as the low energy consumption confirmed that this integrated system is highly applicable for the advanced treatment of triazole fungicides discharged water.

Flutriafol is one of the widely used triazole fungicides in global pesticides market, and its degradation mechanisms are important to develop powerful technologies to remove it. Insight into the kinetics and mechanisms of ·OH-mediated mineralization of flutriafol have been obtained using quantum chemical calculation and electrochemical experiment methods. The complete ·OH-mediated degradation pathway of flutriafol was proposed by density functional theory (DFT) simulation and the potential energy surface was mapped out for possible reactions. On the basis of DFT calculations, the optimal ·OH-mediated mineralization mechanism of flutriafol was revealed, and a series of intermediates were observed accumulated in the degradation process, most significance among which were (2-fluorophenyl) (4-fluorophenyl)-Methanone, phenol, dihydroxybenzenes, benzoquinones, muconic acids, maleic acids, oxalic acids and formic acid. To give deeper insight into the ·OH-mediated reaction mechanism, the electrostatic potential (ESP) and average local ionization energy (ALIE) analysis were conducted for o-benzoquinone and p-benzoquinone. The proposed mechanism was further validated by electrochemical experiments at TiO2-NTs/SnO2-Sb/PbO2 anode. The main intermediates were identified and quantified by experimental method, indicating that the proposed ·OH-mediated degradation mechanism derived from DFT calculations was feasible. These detailed findings could be instrumental for a comprehensive understanding of the ·OH-mediated mineralization mechanism of flutriafol and the similar contaminants.

Novel ultrafiltration-adsorption membranes (UFAMs) were designed via decorating the walls of membrane internal pores with polydopamine (PDA) nanoparticles for heavy metals removal. Specially, self-polymerized dopamine solution was penetrated through the polyethersulfone (PES) UF membrane from reverse direction (i.e., from bottom to top) by circulatory filtration, leading to the formation of a PDA nanoparticle coating around the walls of finger-like pores (labeled as PES/PDA-R). The conventional PDA-decorated membrane (labeled as PES/PDA-F) prepared with forward filtration was used for comparison. The results indicated that the introduction of PDA nanoparticles on the walls of internal pores endowed the PES/PDA-R membrane with enhanced UF performance and remarkable adsorption capacity for heavy metals. PES/PDA-R membrane exhibited ascendant bovine serum albumin (BSA) rejection (92.9%) and maintainable pure water flux (166 L/m 2 h). The static adsorption capacities for Pb 2+ , Cd 2+ and Cu 2+ on PES/PDA-R membranes were 20.23 mg Pb/g, 17.01 mg Cd/g and 10.42 mg Cu/g, respectively, which are 1.69, 2.25 and 1.91 times higher than that of the PES/PDA-F membranes. Importantly, dynamic filtration experiments revealed 4.13 times adsorption capacity for Pb 2+ was achieved on PES/PDA-R membrane over PES/PDA-F membrane. The significant enhancement of dynamic adsorption capacity on PES/PDA-R membrane is derived from the three dimensional distribution of PDA nanoparticles on the cross section of PES membrane which provide the more active sites and increase the contact time between PDA and metal ions. This novel approach paves a way to design specific composite membranes for a cost-effective water treatment.

Developing oxygen reduction reaction (ORR) catalysts with high performance at low cost is critical for the practical application of fuel cell technology. In this work, novel Fe-N-C hybrid mulberry-like fibers (denoted as MB-CFs), which are composed of hollow mesoporous carbon spheres (HMCSs) encapsulated in N-doped carbon fiber, have been synthesized by a facile electrospinning method. These composite materials have successfully combined together the merits of HMCSs (i.e. high surface area and micro-meso-macropores) and carbon fibers (i.e. large aspect ratio, high conductivity, and favorable flexibility), as well as graphitic and multilevel structure, which are highly desired as ORR catalysts. The electrochemical measurements demonstrate that the designed MB-CFs-0.6 was the best among the series, which possess outstanding activity, excellent durability and selectivity toward ORR catalytic reaction in both alkaline and acid media. Considering the favorable structure and ORR performance of this novel carbon fiber, other nanoparticles (heteroatom or metal-doped hierarchical porous carbon spheres, hollow metal oxides, etc.) could also be electrospun into functional carbon fibers for energy storage and conversion.

In order to accelerate the aerobic granulation and thus promote the degradation efficiency of highly refractory compounds such as pyridine in aerobic granular system, enhanced aerobic granulation based on biochar addition was developed in this study. The results indicated that the sludge formed in the reactor with the addition of biochar possessed excellent settling property, high biomass retention and excellent degradation ability. Extracellular polymeric substances (EPS) contents in granular sludge increased noticeably at the presence of biochar, indicating the stimulation of EPS secretion by biochar. High-throughput sequencing analysis exhibited that enhanced granulation and pyridine degradation could be attributed to the enrichment of aggregation-related species and pyridine degrading species at the presence of biochar. This study indicated that adding biochar is a simple and effective method for the initiation of granulation to facilitate the treatment of high-strength refractory wastewater.