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The graphical abstract was designed to characterize the viewpoint that our manuscript wanted to convey. The pristine idea comes from the "traditional Chinese dragon boat race". Three people, the drummer (white), the rower (yellow) and the helmsman (green), drive the dragon boat (the boat in which they ride) forward quickly and ride the waves. The picture corresponded with the standpoint that the different strategies for achieving the goals of (i) absorption of visible light; (ii) inhibition of charge recombination; (iii) utilization of photogenerated carriers, thus synergistically improving the performance of the photocatalyst and the degradation efficiency of the PFOA. Compared with graphical abstracts in other reviews (pie chart with method classification), we believe that the artistic graphical abstract can impress readers more. [Display omitted] • Doping with metal/non-metal elements can adjust the bandgap to enhance the absorption of visible light. • Trapping or rapid migration of electrons can inhibit photogenerated electron-hole recombination. • Constructing semiconductor heterojunctions can improve the degradation efficiency of PFOA. • The high-entropy materials can be used as excellent photocatalysts. • Future research directions about photocatalysts for the PFOA photodegradation were given. Perfluorooctanoic acid (PFOA) is a synthetic organic compound widely used in commercial and industrial products. Due to its high persistence, bioaccumulation, and toxicological properties, PFOA poses a serious risk to human health and the natural environment. Photocatalysis, as a clean energy technology for the potential removal of PFOA, has attracted considerable attention in recent years. However, the efficiency of the photodegradation of PFOA is limited mainly due to three reasons: (i) low light utilization, (ii) rapid electron-hole recombination, and (iii) low utilization of photogenerated carriers. Therefore, this review aims to provide a systematic summary based on current state-of-the-art approaches to designing and fabricating semiconductor photocatalysts to improve the rate of PFOA degradation. Specifically, the fundamental mechanism of photodegradation processes is first introduced, followed by a review of the improvement approaches for enhanced visible-light absorption of photocatalysts, inhibition of electron-hole recombination, and utilization of photogenerated carriers. In addition, this review discusses the principal effects of different semiconductor modifications on their performance in photodegradation systems. Finally, a summary and outlook on the challenges and future directions of semiconductor photocatalysis in practical water treatment are provided. This review contributes to understanding photodegradation mechanisms, promoting photocatalyst development, and opening a pathway for the sustainable treatment of PFOA in water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel Mn-FeS 2 /MWCNT heterogeneous Fenton catalyst were synthesized. • Mn-FeS 2 /MWCNT showed excellent performance in actual wastewater treatment. • The co-enhancement effect of Mn doping and combination of MWCNT was clarified. • Mn doping into FeS 2 promoted the generation of superoxide radical. • The Fe-S-C and Mn-S-Fe bond improved stability and reactivity of catalyst. Recently, pyrite (FeS 2) has been discovered as a promising heterogeneous Fenton catalyst due to the excellent generation of Fe(II). However, the limited inherent catalytic efficiency and poor stability hinder its wide application in wastewater treatment. Herein, a novel carbon nanotube-loaded Mn-doped FeS 2 (Mn-FeS 2 /MWCNT) catalyst was synthesized for high radical production and durable Fenton catalysis. The optimized Mn-FeS 2 /MWCNT exhibited 100 % of bisphenol A elimination within 15 min, which was ∼174- and ∼20-fold than that of FeS 2 and FeS 2 /MWCNT, respectively, and Mn-FeS 2 /MWCNT demonstrated remarkable stability after five cycles (less than 0.8 mg/L Fe leaching in each cycle). The generation of hydroxyl radicals (OH) and superoxide radicals (O 2 −) was enhanced with Mn doping and the introduction of MWCNTs. Mechanistic studies and DFT calculations revealed that Mn doping tuned the electron density between Fe and Mn in the Fe–S–Mn linkage, further improving the H 2 O 2 absorption energy on the Mn-FeS 2 surface for radical generation. Introducing MWCNTs improved the reactivity and stability of the catalyst by electron transfer of the Fe–S–C bond. This work determined the co-enhancement effect of metal sulfur links and sulfur carbon bonds on pyrite-based materials and provides a promising catalyst for wastewater remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • TiO 2 -BNTs/SnO 2 -Sb REM was prepared and used to dispose ROC wastewater. • The dissolved organic matters in ROC could be effectively removed. • Prominent anti-fouling performance and long service lifetime (4.6 years) was achieved. • The competitive energy consumption (10.5 kWh·kg COD−1) achieved in ROC treatment. With the wide application of reverse osmosis technology in municipal wastewater treatment, the abundance of generated reverse osmosis concentrates (ROC) has become a significant challenge for water ecosystems. In this work, a fabricated TiO 2 -BNTs/SnO 2 -Sb reactive electrochemical membrane (REM) was used to dispose of municipal ROC wastewater. The effects of the TiO 2 nanotube array (TiO 2 -BNTs) interlayer, current density, initial pH and flow rate on the COD removal of ROC were investigated. In addition, the 3D-EEM fluorescence spectra showed that humic acid-like substances and soluble microbial byproduct-like substances could be removed effectively. GC-MS analysis indicated that most organics, including aldehydes, phenols, ethers, nitriles, ketones, silanes and alcohols, were eliminated after treatment. The REM also exhibited prominent membrane anti-fouling performance in high-salinity wastewater. After 20 cycles, the transmembrane pressure (TMP) was only slightly changed (within 3 kPa) compared to that of the first cycle. Two key parameters, i.e., service lifetime and energy consumption, were investigated in ROC treatment. The service lifetime reached 31350 h (3.5 years, 20 mA cm−2) in 0.5 M NaCl solution and 40390 h (20 mA cm−2, 4.6 years) in actual wastewater, which is highly competitive with previously reported electrodes. Energy consumption reached 10.5 kWh·kg COD−1 in actual ROC wastewater, which is more acceptable compared with current reported electrochemical technologies and exhibits great application prospects for TiO 2 -BNTs/SnO 2 -Sb REMs. [ABSTRACT FROM AUTHOR]

• Novel multiframe flat membrane contactor (MFMC) was designed for lithium extraction. • Loss of extractant TBP was reduced by 91% using MFMC comparing to liquid–liquid extraction. • Module efficiency of 90% was found in scaling-up. • Height of transfer units (HTU) of MFMC was projected to be about 3 m after future optimization. Comparing to conventional liquid–liquid extraction, membrane extraction is an efficient and environmentally friendly separation technique to recover lithium from the salt-lake brine. Development of suitable hydrophilic solvent resistant nanoporous membranes for membrane extraction has been based on bench-scale small module. Because module design has significant impact on the performance, this work reported a novel multiframe flat membrane contactor module (MFMC) for lithium extraction from synthetic brine. The hydrophilic poly (ethylene-co-vinyl alcohol)/sulfonated poly(ether ether ketone) membrane supported with polypropylene nonwoven (EVAL/SPEEK-NW) was prepared for module evaluation. The membrane mass transfer coefficients k m of 1.1 × 10-6 m/s was obtained by Wilson plot. The global mass transfer coefficient K e increased from 4.5 × 10-7 m/s to 9.9 × 10-7 m/s following the flow velocity from 0.4 to 1.8 cm/s in membrane extraction. We further evaluated the characteristics of MFMC via height of transfer units (HTU) and module efficiency (ME). High module efficiency of 90% was obtained, demonstrating MFMC's efficient flow distribution. HTU of 28 m was estimated and was expected to decrease to 3 m by optimizing thickness of gasket and spacer as well as membrane performance. The MFMC module effectively reduced the loss of tributyl phosphate (TBP) by 91% comparing to liquid–liquid extraction. The research presented herein provides a flat membrane module design for potential future application of membrane extraction in wide applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel vacuum-thermal assisted hybridization strategy of MOF on COF is proposed. • Construction of a novel sunflower-like MOF@COF hybrid system with strong π-π bond stacking. • The photocatalytic pathway can be adjusted by regulating the ratio of MOF and COF. • Sacrificant-free photocatalytic CO 2 reduction for methane production with excellent activity. Metal-organic framework (MOF) and covalent organic framework (COF) hybrid materials have drawn much research attention in the field of photocatalysis due to their complementary advantages, massive specific area, customizable structure and performance, and suitable band gap. Herein, the MOF@COF hybrid platform with a novel sunflower-like strong π-π bond stacking was formed by introducing the preformed synthetic COF into the MOF precursor solution and modulating its morphology by vacuum thermal-assisted growth. More importantly, the synthesized MOF on the COF hybrid platform with multiple active centers exhibits excellent catalytic activity in the sacrificial agent-free photocatalytic CO 2 reduction reaction under simulated sunlight. Additionally, the maximum CH 4 yieldrate of the synthesized PCN-222-Cu@TpPa-1 (1:2) reached 21.27 μmol g-1h -1, with an AQY (apparent quantum yield) about 10.46 % (in pure water system, λ = 550 nm) and a methane selectivity of about 27.25 %. The best performance of PCN-222-Cu@TpPa-1 is approximately 4.3 times higher than that of pure PCN-222-Cu and 100 times higher than that of the reported NH 2 -MIL-125(Ti) NMB. The selectivity of the products CO and CH 4 can be improved by adjusting the ratio of MOF and COF. Finally, the goal of providing an optimal photocatalytic platform for increased photocatalytic CO 2 reduction with highly effective morphology-tunable MOF@COF was expanded upon by a potential photocatalytic reaction mechanism, which was suggested based on the analysis of experimental results. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hierarchical ZnO@ZnFe 2 O 4 \CdS cages were designed and fabricated. • Stepped band heterostructure accelerates charge transfer and separation. • Hierarchical hybrid possesses more active sites and enhanced visible-light absorption. • Hierarchical hybrid exhibits excellent photocatalytic CO 2 reduction activity. Converting CO 2 into chemical energy by efficient photocatalysts is a promising strategy to meet the increasing energy demand and decrease greenhouse gases. In this work, hierarchical ZnO@ZnFe 2 O 4 hollow polyhedrons decorated with CdS quantum dots were designed and prepared to improve photocatalytic CO 2 reduction performance. The facile strategy for the synthesis of hierarchical ZnO@ZnFe 2 O 4 hollow polyhedrons involves the synthesis of ZnO hollow polyhedrons derived from the thermal decomposition of 2-Methylimidazole zinc salt (ZIF-8) precursor and in situ generating Zn-Fe layer double hydroxide nanosheets on the surface of ZnO hollow polyhedrons and subsequent thermal treatment. More importantly, the in situ formation of ZnFe 2 O 4 nanosheets can form strong interaction between ZnO hollow polyhedrons and ZnFe 2 O 4 nanosheets. The hierarchical hollow polyhedral structure of the ZnO@ZnFe 2 O 4 sample possesses more preferable active sites to promote CO 2 adsorption and reduction process. The prepared hierarchical ZnO@ZnFe 2 O 4 hollow polyhedron sample shows a significantly enhanced performance for photocatalytic CO 2 reduction compared with single-component catalysts (ZnO, ZnFe 2 O 4 , and CdS) with a CO evolution rate of 95.84 μmol g−1h−1. The decoration of CdS quantum dots makes the ternary heterostructure hybrid form multichannel charge transfer path, which further accelerate charge separation and enhance electrons utilization, resulting in a significant improvement of photocatalytic activity. Noticeably, the CO evolution rate reaches 197.66 μmol g−1h−1, 3 and 2 times higher than that of the bare ZnO and binary ZnO@ZnFe 2 O 4 hollow polyhedrons, respectively. This work gives a promising direction to prepare high-active photocatalysts for solar fuel production. [ABSTRACT FROM AUTHOR]

[Display omitted] • The lignin content of the adsorbent is more than 98%. • The adsorption capacity of Cr(VI) ions is up to 703.6 mg/g at 30 °C. • The removal efficiency of the adsorbent for low concentration Cr(VI) ions is up to 99.9%. • The reduction of Cr(VI) to Cr(III) by phenolic hydroxyl drives the adsorption. The development of full-lignin-based adsorbents with high adsorption capacity for the removal of Cr(VI) ions from wastewater has intensively attracted attention. However, it is still a challenge up to now due to the low reactivity and complexity of lignin structure. Herein, a high hydroxyl content demethylated alkaline lignin (DAL) was prepared using AlCl 3 as the modification reagent. With this DAL as the full-lignin-based adsorbent, the adsorption capacity for Cr(VI) was up to 703.6 mg/g at 30 °C. Moreover, when the concentration of Cr(VI) ions was below 100 mg/L, the removal efficiency was high up to 99.9 % by only using 10 mg adsorbent in 50 mL solution. On the basis of the isotherm, kinetic, and thermodynamic model analyses, it could be concluded that the chemisorption occurred in monolayer on the surface of the adsorbent, and the adsorption process was endothermic and spontaneous. The characterizations of the spent adsorbents showed that the adsorption might be driven by the reduction of negatively charged Cr 2 O 7 2- or HCrO 4 - ions to positively charged Cr3+, which could generate strong electrostatic interaction with the oxygen containing groups in lignin. Simultaneously, the toxicity of chromium ions was significantly decreased during the reduction. This work provides a new way to realize high adsorption capacity of Cr(VI) ions by a full-lignin-based adsorbent, and accelerates the high-value utilization of lignin. [ABSTRACT FROM AUTHOR]

• A bulk nitrogen-rich carbon nitride (g-C 3 N 5) photocatalyst was prepared. • Design and synthesis CdS-DETA@g-C 3 N 5 , which exhibit excellent performance for H 2 evolution (14.2 mmol·g−1 · h−1) and ofloxacin degradation (95.4 %). • Enhance the bending of the energy band by adding diethylenetriamine (DETA). The proper design of photocatalysts is essential to improving photocatalytic decomposition of water and degradation of pollutants. In this work, we used nitrogen-rich carbon nitride with high electronic properties combined with CdS-DETA to generate CdS-DETA@g-C 3 N 5 composite, and diethylenetriamine (DETA) was used to enhance the band bending to enable the excellent photocatalytic performance of the photocatalyst. The hydrogen evolution rate (14.23 mmol/(g·h)) of the CdS-DETA@g-C 3 N 5 composite is 7.1, 7.5, and 4.5 times higher than that of g-C 3 N 5 (2.03 mmol/(g·h)), 20CSCN5 (1.89 mmol/(g·h)), and CdS-DETA (3.17 mmol/(g·h)), and the OFLX degradation rate (95.6 %) is 3.4 and 1.5 times higher than that of g-C 3 N 5 and CdS-DETA, respectively. These performance enhancements result from the enhancement of energy band bending, the construction of a built-in electric field (IEF), and the retention of high redox carriers. This work provides new insights into the design of nitrogen-rich carbon nitride-based photocatalyst for efficient photocatalytic degradation and hydrogen precipitation activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • The prepared PEI-JE had the same 3D network structure as the JE. • PEI-JE had a maximum adsorption capacity of 268.93 mg/g at 25 ℃. • Cr(VI) removal rate almost kept unchanged after 10 adsorption/desorption cycles. • Cr(VI) removal was involved in electrostatic adsorption, redox and complexation. • The Cr(VI) adsorbed on the surface of PEI-JE was completely reduced to Cr(III). In the present study, a novel PEI-modified Juncus effuses (PEI-JE) adsorbent was prepared based on the natural 3D network structure of JE via a simple and environmental-friendly method with the help of the ethanol/aqueous solution. SEM, EDS, ATR-FTIR and XPS were performed to reveal the physical and chemical structure of the PEI-JE. The Cr(VI) removal by the PEI-JE was investigated by bath adsorption experiments. Results showed that the developed PEI-JE exhibited the same 3D network structure as the JE, which not only was easy to separate from aqueous solution but also can expose more active sites and facilitate mass transfer. The optimal pH for Cr(VI) adsorption on the PEI-JE was 3, and adsorption equilibrium time was related to initial Cr(VI) concentrations. The adsorption kinetic obeyed pseudo-second-order kinetic model, and the adsorption isotherm showed the best fit with Freundlich model. The calculated maximum adsorption capacity was 268.93 mg/g at 25℃. Coexisting ions including Na+, K+, Al3+, H 2 PO 4 −, Cl−, NO 3 – had no remarkable effect on Cr(VI) adsorption, but the presence of SO 4 2−, HCO 3 – and CO 3 2– caused the efficiency losses of 10.9%, 41% and 66%, respectively. After 10 cycles of adsorption/desorption, Cr(VI) removal rate on the PEI-JE almost kept unchanged, demonstrating that the PEI-JE possessed good reusability. Mechanism study suggested that Cr(VI) removal was involved in a three-step reaction, namely electrostatic adsorption, redox and complexation. Film diffusion was the rate-limiting step and chemical adsorption was the main mechanism. The Cr(VI) adsorbed on the PEI-JE surface was completely reduced to Cr(III), demonstrating that PEI-JE is useful for Cr (VI) removal and detoxification. [ABSTRACT FROM AUTHOR]

[Display omitted] • The dual Z-scheme heterojunction improves the separation and migration efficiency of electron-hole pairs. • The space separation between the oxidation center and the reduction center improves the utilization rate of carriers. • Thiazoles as an electron acceptor to reconstruct electrons on the g-C 3 N 4 surface and adjust its HOMO and LUMO dispersion to improve electron mobility. • ZnCdS@ZnIn 2 S 4 @g-C 3 N 4 -vTA prepared by electrostatic self-assembly, and its intimate interfacial contact shortens the migration distance of carriers. The structural design of the photocatalyst has a great influence on photocatalytic performance. Here, the ZnCdS@ZnIn 2 S 4 @g-C 3 N 4 -vTA with a dual Z-scheme heterojunction structure is prepared by electrostatic self-assembly. It has high photocatalytic hydrogen evolution (11359.9 μmol g−1h−1), excellent OFX degradation performance (95.7%), and good reusability under visible light. The hydrogen production performance of ZnCdS@ZnIn 2 S 4 @g-C 3 N 4 -vTA is about 56, 7, 2 times higher than g-C 3 N 4 , ZnCdS, and ZnIn 2 S 4 , respectively. The excellent photocatalytic performance mainly depends on the following aspects: (1) The dual Z-scheme heterojunction with spatial separation of active centers improves the migration and separation efficiency and utilization of electron-hole pairs. (2) The 4-methyl-5-vinylthiazole (vTA) molecular is grafted to the edge of g-C 3 N 4 by visible light to reconstruct the surface electrons so that the electrons can be transferred to the ZnIn 2 S 4 surface more efficiently to increase the overall carrier transport rate; (3) ZnCdS@ZnIn 2 S 4 @g-C 3 N 4 -vTA prepared by electrostatic self-assembly, and its intimate interfacial contact shortens the migration distance of carriers. In addition, the high specific surface area and pore size of ZnCdS@ZnIn 2 S 4 @g-C 3 N 4 -vTA improves the migration and separation of carriers. Our research provides an expandable idea for designing molecular engineering-based dual Z-scheme heterojunction photocatalysts and nanomaterial composite methods. [ABSTRACT FROM AUTHOR]

[Display omitted] • AMOF was successfully synthesized as a novel PMS activation mediator. • The AMOF/PMS process had robust tolerance of pH and ions for the BPAF removal. • The activation mechanism involved radical and non-radical reactions. • The characteristic byproducts and degradation pathways were discussed in depth. • The toxicity of several byproducts was higher than that of the BPAF. Advanced oxidation processes (AOPs) based on the metal–organic frameworks (MOFs) and peroxymonosulfate (PMS) have been demonstrated as promising methods for the degradation of contaminants. In this study, the degradation of bisphenol AF (BPAF) by activated PMS via amino-modified metal–organic frameworks (AMOF) was investigated thoroughly. BPAF could be efficiently removed (94.1%) in the optimal condition. The decontamination of BPAF could be accelerated significantly with the increasing temperature, and a highly stable degradation performance was observed at a wide pH range. Quenching experiments and electron paramagnetic resonance (EPR) tests revealed that sulfate radical (SO 4 –•), hydroxyl radical (HO•), singlet oxygen (1O 2), and superoxide radical (O 2 –•) were produced synergistically in the AMOF/PMS system. Chloride ion (Cl–) exhibited a dual influence on BPAF removal, while other anions and NOM could hinder the degradation rate mildly. A total of fifty-two intermediates were identified using UHPLC-MS/MS method and four main degradation pathways were proposed based on the density functional theory (DFT) calculation, including the frontier molecular orbital theory (FMO), natural population analysis (NPA), and Fukui function. Finally, the Quantitative Structure Activity Relationship (QSAR) method for Toxicity Estimation Software Tool (TEST) was applied to estimate the accurate toxicity of BPAF and degradation byproducts. This study exhibited the promising potential for the decontamination of BPAF in the water via the AMOF based AOPs. [ABSTRACT FROM AUTHOR]

One-pot synthesis of functional material from waste expanded polystyrene foam, which displays good adsorption performance and reusability for dyes. [Display omitted] • Waste expanded polystyrene foam is transformed into adsorbent. • Adsorbent shows rapid adsorption, high adsorption capacity and good reusability. • Adsorbent shows excellent adaptability to pH and salt solutions. • Adsorbent can easily realize continuous column adsorption process. • Easy adsorption and desorption to achieve the separation of dyes. Many researchers focus on the conversion of waste into reusable materials in recent years. In this study, waste expanded polystyrene foam (WEPS) and 1,2,4-benzenetricarboxylic anhydride (BTA) were used as raw materials to prepare recyclable acylating waste expanded polystyrene adsorbent (WEPS-BTA) by Friedel-Crafts reaction and to recover dyes effectively. The WEPS-BTA was characterized by FT-IR, TGA, BET and SEM. WEPS-BTA showed good performance in a wide range of pH (2–12) and high concentration brine (0.2 M). The maximum adsorption capacity to methylene blue, safranine T, and malachite green were 859.9, 1036.7, and 1197.3 mg/g, respectively. It was found that Freundlich model and pseudo-second-order kinetics could describe the adsorption behavior. This is a heterogeneous, endothermic, and spontaneous multiple adsorption process. The plausible adsorption mechanism was explained by kinetic model, thermodynamic discussion, SEM-EDS, XPS and FT-IR. In addition, WEPS-BTA showed satisfactory reusability without significant loss of the removal efficiency of the three dyes after 5 cycles. Therefore, WEPS-BTA has the advantages of simple synthesis, efficient adsorption, easy recycling and reuse, and stable performance in a harsh environment. Converting waste polystyrene foam to an adsorbent is an economic way of handling waste and providing material for wastewater remediation simultaneously. [ABSTRACT FROM AUTHOR]

To explore an economic Fluoride-adsorbent with high capacity and superior selectivity as well as easy regeneration, a new synthetic strategy was constructed through a hydrothermal procedure with the aid of glucose to prepare high performance adsorbent ZrO 2 -MgO@C composite (CZMC). The adsorption capacity and the selectivity toward fluorine ions were evaluated for the synthesized adsorbents. Through characterizations of XRD, BET, SEM, HRTEM, XPS, etc., the crystal structure, the morphology and the chemical composition of the adsorbents were analyzed, illustrating that CZMC has the desirable structure with high dispersion of metal oxides in the porous carbonized microspheres. The results indicate that ZrO 2 -MgO@C composite show the F-ions adsorption capacity of 184.5 mg/g, with excellent resistance toward disturbance of other anions including NO 3 −, Cl−, SO 4 2−, CO 3 2− and PO 4 3−. DFT calculations show that the adsorption process of fluorine ions occurs spontaneously and accompanied by orbital hybridization of surface atoms. Such composite adsorbent having high adsorption capacity and superior F-selectivity as well as the feature of easy regeneration would possess promising applications in the treatment of waste water containing fluorine ions. • ZrO 2 -MgO@C was investigated for fluoride treatment. • Surface reaction is explored by DFT analysis. • Electrostatic attraction, ion exchange, and surface complexation are adsorption mechanisms. • Theoretical adsorption capacity was 184.5 mg/g. • The adsorbent has good regeneration performance and practical application value. [ABSTRACT FROM AUTHOR]

• How EPS function in RO membrane biofouling is shown for the first time. • EPS in bio-foulants facilitate the adhesion of bacteria to membranes and each other. • High compactness and firm adhesion of bio-foulant indicate severe biofouling. • High EPS content and MW indicate high interaction energy and severe biofouling. The interaction of bio-foulants at the interface of reverse osmosis (RO) membranes is highly correlated with the degree of fouling during wastewater treatment. However, there are few observations showing the micro/nanoscale bio-foulant morphology at the interface and its relationship with the degree of fouling. In this study, two typical bacterial strains (Escherichia coli CGMCC1.3373 and Bacillus cereus CR19) present in reclaimed water were used to test their fouling potential and reveal their interactions with RO membranes. B. cereus , a typical chlorine-resistant bacterium, exhibits significantly higher extracellular polymeric substance (EPS) content and higher interaction energy with membranes. The rate of decrease in membrane flux in the B. cereus group was 1.5 times higher than that in the E. coli group. By rapidly freezing the bio-foulants and examining the micro/nanoscale morphology around their interface with RO membranes, it was revealed that the membrane was fouled by stacked bacterial cells with EPS adhering to each other and to the RO membrane surface. B. cereus secreted more EPS, stacked more compactly, and adhered to the RO membranes more firmly than E. coli , resulting in more severe fouling. To our knowledge, this is the first study to demonstrate that the micro/nanoscale morphology of the interface between bio-foulants and RO membranes indicates the degree of fouling. [ABSTRACT FROM AUTHOR]

[Display omitted] • The adsorbent shows the high adsorption capacities for Pb2+ and Ni2+ ions. • The adsorption efficiency can still maintain over 85% after 5 cycles. • The chemisorption occurs in monolayer during the adsorption process. • The spent adsorbent can be utilized as the electromagnetic wave absorber. • The electromagnetic wave absorber exhibits excellent adsorption performance. Graphene oxide/magnetic lignin-based nanoparticles (GO-MLNPs) were successfully prepared for adsorbing heavy metal ions. Then the spent adsorbents (M2+@GO-MLNPs) were unprecedentedly applied as efficient electromagnetic wave absorption (EMWA) materials. The structures and performances of the prepared GO-MLNPs were comprehensively characterized with various analytical methods. Adsorption experiments were studied in detail to identify the influence of various factors. The maximum adsorption capacities (Q max) of Pb2+ and Ni2+ ions would be up to 147.88 and 110.25 mg/g, respectively. Notably, the adsorption rate could be maintained over 85% after 5 sorption–desorption cycles. After the adsorption, in order to reduce the secondary pollution, the spent adsorbents were recycled as novel EMWA materials via carbonization process (M2+@GO-CMLNPs). Surprisingly, the reflection loss (RL) of Ni2+@GO-CMLNPs reached −39.2 dB at 4.56 GHz under the thickness of 5.0 mm. In short, the low-cost and renewable GO-MLNPs not only have the large adsorption capacity of heavy metal ions but also can be reused after adsorption process as efficient electromagnetic wave (EMW) absorbers. [ABSTRACT FROM AUTHOR]

[Display omitted] • The synergy of EP-zone and BSR-zone fully promoted the multi-pathway conversion and utilization of O 3. • The dual-zone synergistic catalytic reaction effectively inhibited the accumulation of the in. • A possible mechanism for the dual-zone synergistic catalytic reaction in the 3D/E-P process was provided. • The E-GAC (N) -P system offered higher COD removal and lower energy consumption in actual wastewater. The electro-peroxone (E-P) technology exploits in-situ generated H 2 O 2 to drive the peroxone reaction, which not only improves degradation efficiency but also utilizes wasted O 2 in the process of O 3 generation. However, limited by the cathodic interface reaction, a quantity of O 3 diffused into the bulk solution could not be effectively utilized. To address this problem, a dual-zone E-P process was proposed in combination with nitrogen-doped granular activated carbon (GAC (N)) and a 2 electron-oxygen reduction reaction (2e-ORR) system, i.e., the E-GAC (N) -P system. Combining EPR and quenching experiments, the addition of GAC (N) was proven to alter the ·OH-dominated reaction routine of E-P to the ·OH and ·O 2 – synergistic routine, which achieved a high pollutant removal efficiency of up to 98.75 % and a reaction rate constant of 0.3838 min−1 (3.5 times that of the traditional E-P system). In terms of the mineralization mechanism, the E-GAC (N) -P system not only effectively inhibited the accumulation of intermediate products but also increased the total organic removal by 63.94 %. Moreover, the efficient removal of COD in actual wastewater also confirmed that the E-GAC (N) -P system had excellent mass transfer efficiency and 36.9 % lower electric energy consumption than did the traditional E-P system, indicating good practical application prospects. [ABSTRACT FROM AUTHOR]

• The motion and capture of spherical particles in a micro cross-shaped channel are studied. • The orbital motion of finite-size particles within confined vortex is revealed. • The window of particle capture is modified by unsteady engulfment flows. Vortex-induced particle capture has attracted widespread attention as an effective tool for particle preconcentration or manipulation. In this work, the motion and capture of particles in confined vortices in a micro cross-shaped channel are explored by a high-speed camera within Reynolds numbers ranging from 10 to 450. Micro Laser-Induced Fluorescence (μLIF) and numerical simulation are used to visualize flow structures. Results demonstrate that a buoyant particle undergoes an attenuation oscillation, finally arriving a periodic orbit (i.e., a limit cycle) inside the vortex. The formation of the orbit is closely associated with the development of recirculating flows in the microchannel. With an increase in the number of captured particles, the average distributions of particles show particle exchange corridors between capture regions and mainstream, which is caused by interactions between particles or flow instability. Once the particle density exceeds the fluid density, the particle periodic orbits disappear, and particles move directly or spirally to the outlets. Moreover, oscillation induced by vortex merging and splitting influences the quantities and distributions of capture regions, as well as the migration paths of buoyant particles. In addition to particle capture at the channel center, a portion of captured particles is observed near channel walls. [ABSTRACT FROM AUTHOR]

• PPy-modified natural eggplant composite aerogel was first developed. • PPy@eggplant possessed impressive shape recovery capacity after absorbing water. • Simultaneous evaporation and adsorption performance was reasonably evaluated. • PPy@eggplant aerogel showed a high and stable evaporation rate of 2.05 kg·m−2·h−1. • A mechanism of simultaneous evaporation and adsorption was proposed. Solar water evaporation has proven to be one of the most effective approaches to generate clean water. However, simultaneous clean water generation and heavy metal ion removal is challenging and urgent for the treatment of wastewater containing heavy metal ions. Herein, polypyrrole (PPy)-modified natural eggplant (PPy@eggplant) aerogel was developed to effectively address the aforementioned problems. The resultant PPy@eggplant aerogel possessed impressive shape recovery capacity after absorbing water regardless of multiple squeezing and twisting, which contributed to usage stability in long-term applications. Moreover, the PPy@eggplant aerogel achieved solar light absorption of 98.48 % due to PPy uniform distribution and multiple light diffraction/scattering in the porous structure (porosity of 92.16 %), excellent water replenishment capacity (water droplet fully spread within 118 ms), and extremely low thermal conductivity (0.039 W·m−1·K−1). Thus, the PPy@eggplant aerogel demonstrated a high evaporation rate of 2.05 kg·m−2·h−1 and a simultaneous Cr6+ adsorption capacity of 27.83 mg·g−1 for treating dye water with Cr6+ ions. Additionally, the PPy@eggplant aerogel preserved the evaporation rate after a 10-h test, indicating long-term stability in practical applications. In conclusion, the impressive shape recovery capacity, high evaporation performance, and satisfactory Cr6+ adsorption ability make the PPy@eggplant aerogel a good alternative for treating wastewater, especially wastewater with heavy metal ions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co-ZrP is successfully prepared through absorbing Co2+ onto ZrP and calcining. • PNT is completely degraded in the Co-ZrP/PMS system within 10 min. • PNT rapid degradation is mainly attributed to •OH and SO 4 •−. • ZrP as a carrier significantly improves the catalytic performance of cobalt oxide. • Co-ZrP exhibits excellent stability, reusability and universality. Herein, zirconium phosphate as a recycled material was used for the first time to support cobalt (Co-ZrP) serving as a catalyst for activating peroxymonosulfate (PMS) to remove phenacetin (PNT). It was found that PNT (5 mg L−1) was completely eliminated in the Co-ZrP (0.2 g L−1)/PMS (2 mM) system in an initial pH range of 5 to 7 within 10 min. The pseudo-first-order rate constant of PNT degradation by PMS combined with Co-ZrP was 0.625 min−1, far faster than those with ZrP (0.0065 min−1) and with Co 3 O 4 (0.104 min−1). The introduction of HA and HCO 3 − significantly inhibited PNT removal, while the addition of H 2 PO 4 − accelerated PNT elimination in the Co-ZrP/PMS system. Nevertheless, PNT could still be completely removed by Co-ZrP-activated PMS in actual water. Recycling experiments indicated that the degradation efficiency of PNT could reach 98 % after four cycles and calcining Co-ZrP could completely restore its catalytic activity. In addition, effective decomposition of chloramphenicol, bisphenol A, sulfamethazine and rhodamine B was also achieved by Co-ZrP-activated PMS within 15 min. Hence, the combination of Co-ZrP and PMS had great potential in removing organic pollutants from water environment. EPR analysis and quenching tests suggested that the rapid degradation of PNT was mainly ascribed to the generation of •OH and SO 4 •− in the Co-ZrP/PMS system. Based on HPLC-HRMS analysis, the main degradation products were determined and the possible degradation pathways were further proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • An amino acid ionic liquid [TEPAH][Pro]/NPA/H 2 O was proposed as a phase change adsorbent. • The absorption loading of [TEPAH][Pro]/NPA/H 2 O is 2.01 mol·mol−1, the rich phase viscosity is 8.06 mPa·s. • The efficiency of the 5th cycle of [TEPAH][Pro]/NPA/H 2 O was 80.1%. • The heat duty of [TEPAH][Pro]/NPA/H 2 O is 2.39 GJ·t CO 2 -1, which was 37% lower than that of 30 wt% MEA. • The CO 2 capturing reaction of [TEPAH][Pro]/NPA/H 2 O is a fast pseudo-first-order reaction. In order to overcome high heat duty and poor regeneration efficiency of existing chemical absorbent, a novel aqueous amino acid ionic liquids (AAILs) phase change absorbent with tetraethylenepentamine (TEPA) as cation, L-proline (L-Pro) as anion and N-propanol (NPA) as phase separator was proposed in this study. [TEPAH][Pro]/NPA/H 2 O owned the maximum absorption loading of 2.01 mol CO 2 ·mol absorbent−1, and the rich phase viscosity was only 8.06 mPa·s. Moreover, its desorption efficiency was 84.4% while the 5th cyclic loading kept above 1.61 mol CO 2 ·mol absorbent−1. With the presence of NPA, the rich phase only accounted for 41% of the total volume while it contained 99.3% of CO 2 products. The heat duty was only 2.39 GJ·t CO 2 -1, which was 37% lower than that of 30 wt% ethanolamine (MEA) aqueous solution. Meanwhile, the reaction mechanism and product distribution were revealed by 13C NMR and the mass transfer kinetics was investigated using the wetted wall column. The products in the rich phase mainly consisted of carbamate, hydrogen carbonate, propyl carbonate and water while the main component of the lean phase was NPA. The reaction followed a fast pseudo-first order reaction. At 313.15 K, the rate constant of fresh absorbent was 51346 s−1, which showed a decreasing trend with the increase of absorption loading at 313.15 K. The second order reaction rate was calculated by: k 2 = 9.88 × 109exp(-3591.2/T), where the reaction activation energy was only 29.86 kJ·mol−1. [ABSTRACT FROM AUTHOR]

[Display omitted] • The AFIL [TEPAH][AICA]/NPA/EG was developed for CO 2 capture. • There were no HCO 3 - products in the absorption, so the corrosion rate of the saturated AFIL to carbon steel was very low. • The increase in absorption loading weakened the CO 2 absorbing ability of the AFILs, which led to the decrease in the K G. • The relationship between k 2 and temperature was expressed as k 2 = 7.2075 × 10 8 exp - 3093.5 T . Extensive energy consumption is a challenge for developing industrial carbon capture absorbents. A novel amino functionalized ionic liquid (AFIL) organic solution, tetraethylene pentamine 5-amino-4-imidazolecarboxamide/n-propanol/ethylene glycol ([TEPAH][AICA]/NPA/EG), is considered as a promising absorbent due to its high CO 2 absorption capacity and low energy consumption. However, its industry application potential still needs to be further evaluated for carbon capture process. In this work, thermodynamics, kinetics and corrosive behavior of [TEPAH][AICA]/NPA/EG solution were investigated. The regeneration energy consumption was 2.30 GJ⋅t−1 CO 2 , which was 39.5% lower than the benchmark monoethanolamine (MEA) solution. The mass transfer reaction kinetic model was established, showing that the reaction between CO 2 and [TEPAH][AICA]/NPA/EG solution followed fast pseudo-first-order. The enhancement factor and reaction rate constant increased with the increase of absorption temperature, while they showed a decreasing trend with the increase of absorption loading. The relationship between the second-order rate constant and temperature was expressed as k 2 = 7.2075 × 10 8 exp - 3093.5 T . The activation energy was 25.72 kJ·mol−1. During absorption process, the dominant mass transfer resistance gradually changed from gas phase to liquid phase. In addition, the absorbent presented non-corrosive behavior after saturated absorption, which was superior than the MEA absorbent for storage and transportation in the carbon capture technology. To be concluded, the above results showed that the [TEPAH][AICA]/NPA/EG solution owned great potential for future industrial application. [ABSTRACT FROM AUTHOR]

[Display omitted] • A versatile strategy is proposed to construct heterojunction nanofiber membranes and effectively capture PM. • Composite membranes exhibit remarkably enhanced filtration performance under light illumination. • Filter demonstrates excellent filtration efficiency even at high PM concentration and air flow velocity conditions. • The electrostatic field of filter membranes with heterojunction can be regenerated with light. Particulate matter (PM) pollution has posed a severe threat to the environment and human health. Especially for submicron-level fine particulate PM 0.3 , it is still difficult to achieve high-efficiency filtration. Herein, we loaded TiO 2 /g-C 3 N 4 (TCN) heterojunction photocatalyst on polystyrene/polyacrylonitrile (PS/PAN) multiscale nanofiber membranes by a simple one-step blending electrospinning technique. Due to the strong long-range electrostatic force of the built-in electric field, the composite membrane has a remarkably enhanced filtration effect under light. Even under harsh conditions with a high PM 0.3 concentration of more than 1,800,000 m−3 and a high flow rate of 25 L/min, it still has a high filtration efficiency of greater than 98.5%, an increase of about 20% compared with dark conditions, and the pressure drop is only low to 94 Pa. More importantly, the electrostatic field can be regenerated with light, and this preparation strategy can be effectively extended to other photocatalyst heterojunctions. [ABSTRACT FROM AUTHOR]

• Microwave flash evaporation(MFE) process could be utilized to concentrate sulfuric acid. • Power consumption and heat transfer of concentration process were analyzed. • Clean production mode averts the corrosion and the pollution of products. The ameliorative microwave flash evaporation system (MFE) was utilized to concentrate and distillate waste sulfuric acid, the system may overcome the problems of equipment corrosion, product pollution, high energy consumption, long process flow, and low heat transfer rate during recovery process of waste sulfuric acid. The dilute sulfuric acid with mass fraction of 75 wt% was used as experimental medium, 5 experimental cases was generated to verify the effects of MFE with the conditions of different volume, microwave power and depressurization rate. Experimental results demonstrated that the sulfuric acid could be concentrated to mass fraction of 85–95%, and the heating efficiency was among 30% to 80%, heat transfer volume coefficient was among 100 J/K·L-1 to 500 J/K·L-1 with the combination of vacuum and microwave heating during flash evaporation process. Thermal process analysis indicated that the interaction among experimental factors affected concentration and distillation process. At last, we gave the modeling and process optimization method for concentrating sulfuric acid through MFE process based on analyzing those experimental cases. [ABSTRACT FROM AUTHOR]

[Display omitted] • An anionic covalent organic polymer (COP) with the so far fastest cationic dye adsorption kinetics is reported. • The adsorption mechanism is elucidated via comparative experiments and computer simulation. • The excellent performance is demonstrated to be attributed to 1 + 1 > 2 synergy between carbonyl and hydroxyl groups. • An automatic and recyclable water treatment device is constructed based on the anionic COP. • This work suggests that non-porous COPs can also be excellent adsorbents via the synergy of functional groups. Rapid and highly efficient removal of organic dyes from polluted water is of great significance for environmental protection and water resources management. Herein, an anionic covalent organic polymer (COP), denominated as COP OH+CO , with the fastest cationic dye adsorption kinetics so far was prepared and packed into solid phase extraction cartridges for rapid and automatic water treatment. As-prepared COP OH+CO contains abundant hydroxyl and carbonyl groups. Compared to COP OH and COP CO , other two COPs containing only hydroxyl and carbonyl, respectively, COP OH+CO gives a maximum adsorption capacity of 813 mg·g−1 towards cationic dye methylene blue (MB), which is about 4.6 times the sum of those of COP OH (42.4 mg·g−1) and COP CO (135 mg·g−1), suggesting the existence of 1 + 1 > 2 synergy between carbonyl and hydroxyl groups. Such a synergy is well demonstrated by theoretical calculation, which shows that the mutual penetration distance of electrostatic potentials in MB/COP OH+CO complex (4.722 Å) is much larger than those in MB/COP OH (0.443 Å) and MB/COP CO (1.602 Å). Although the rapid synthesis endows COP OH+CO with very poor porosity, the resulted surface adsorption avoids the long-term mass transfer, thus giving an ultra-fast adsorption kinetics with a so far fastest adsorption rate constant of 0.17 g·mg−1·s−1. This work demonstrates that by using the synergetic effect of surface functional groups, rapidly synthesized non-porous COPs may work as promising adsorbents for fast adsorption of targets. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effects of solid particles on liquid–liquid extraction were revealed. • Impacts of rotor structures of high shear mixer on extraction were assessed. • Equipment performance is highly related to vortex and turbulent characteristics. • Machine learning algorithms were used for prediction of mass transfer coefficient. The liquid–liquid extraction process with solid particles is of practical importance in the chemical industry. Consequently, the inline high shear mixer (HSM) was employed for the process intensification, and the effects of particle size and concentration, rotor revolution speeds, and rotor structural parameters were revealed in this work. Results indicate that increasing the rotor revolution speed remarkably promotes mass transfer performance. The extraction efficiency (E) and mass transfer coefficient (K L a) increase at low revolution speeds, yet mainly decrease with the elevated particle concentration. The larger particle size is more unfavorable to mass transfer. E and K L a first decline and then increase with the raised rotor outer diameter, and more rotor teeth correspond to higher E and K L a. Increasing the forward teeth angle promotes liquid–liquid extraction. The relationship between K L a and key parameters is established via machine learning algorithms with high accuracy for HSM design and optimization. [ABSTRACT FROM AUTHOR]

[Display omitted] • A Janus ZIF-8/P(AN-MA) MF membrane is fabricated via self-assembly and in-situ interfacial reaction methods on one side of HP(AN-MA) membrane prepared by TIPS combined with hydrolysis methods. • The ZIF-8/P(AN-MA) hybrid MF membranes are superoleophobic underwater on the PEI side while super-hydrophobic under oil on the ZIF-8 side. • The ZIF-8/P(AN-MA) hybrid MF membranes have efficiently and accurately separate oil-in-water (PEI side) and water-in-oil (ZIF-8 side) emulsions at a low pressure. • Janus ZIF-8/P(AN-MA) hybrid MF membrane exhibits excellent anti-oil-fouling and anti-water-fouling properties. The separation of oil-in-water and water-in-oil emulsions with high efficiency and environmental friendly remains a challenge in the past decade. This work describes a new method to improve the trade-off of the poly(acrylonitrile- co -methyl acrylate) (P(AN-MA))-based membrane for water/oil separation. P(AN-MA) microfiltration (MF) membrane was fabricated via thermally induced phase separation (TIPS) method in this study. Then, some of the –CN groups and –COOCH 3 groups were converted to –COOH groups via hydrolyzing. Finally, the selected wettability was attained by grafting PEI on one side while ZIF-8 was anchored to the other side via self-assembly and in-situ interfacial reaction methods. The ZIF-8/P(AN-MA) hybrid MF membranes are superoleophobic underwater on the PEI side while super-hydrophobic under oil on the ZIF-8 side, which can efficiently and accurately separate oil-in-water and water-in-oil emulsions at a low pressure (0.01 MPa). The separation fluxes of the PEI side were as high as 3053 L/m2 h and 1035 L/m2 h respectively, for the surfactant-free mixtures and surfactant-stabilized emulsions. For water-in-oil emulsions, the fluxes were up to 2316 L/m2 and 878 L/m2 h on the ZIF-8 side, respectively. The separation efficiency of all the mixtures and emulsions was higher than 97.5 %. Moreover, the Janus membranes showed excellent anti-oil-fouling and anti-water-fouling properties on the two sides of the membranes, as well as remarkable durability during the 10 cycles in oil/water separation. Hence, Janus ZIF-8/P(AN-MA) hybrid MF membranes show potential application prospects in oil/water separation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zn-ZIF-65/PAN ES membrane are firstly fabricated as PMS activators. • Zn-ZIF-65/PAN/PMS system showed high RSE when degrade CIP. • Zn-ZIF-65/PAN are renewable through layer-by-layer self-assembly. • SO 4 ·−, ·OH, and 1O 2 was generated to form radical and nonradical process. • CIP was degraded into eleven intermediates through mainly-three pathways. A novel peroxymonosulfate (PMS) catalyst, zinc-based metal–organic framework electrospinning (ES) nanofibers membrane (short for ZIF-65/PAN) was firstly fabricated and used for the degradation of aqueous ciprofloxacin (CIP). Physicochemical properties, catalytic performance, stability, reusability, and the regeneration of ZIF-65/PAN was observed and conducted. Influence of various parameters including ZIF-65 loading content, reaction temperature, initial pH, and competitive organic molecules on CIP degradation was investigated. Reactive active species and degradation intermediates that involved in ZIF-65/PAN/PMS/CIP process were identified. Corresponding reaction mechanisms were speculated. The results indicate that the easy-separation ZIF-65/PAN nanofibers exhibit high efficiency for PMS activation, 89.2 % of CIP was degraded within 60 min, with up to 87.5 % of PMS utilization efficiency. ZIF-65/PAN was renewable through simple layer-by-layer self-assembly, thus shows good prospect in future applications. 26.4 % of surface Zn2+ of ZIF-65/PAN exists in the form of + III oxidation state after activation, indicating the role of zinc catalytic site. Through activation, oxidative active species SO 4 ·−, ·OH, and 1O 2 was generated, CIP was thus degraded through mainly-three pathways. This study provides novel ideas for the application of MOF-based membrane on PMS based advanced oxidation processes. [ABSTRACT FROM AUTHOR]

[Display omitted] • NF can simultaneously remove traditional PFOS/PFOA and emerging PFAS homologous. • MW and logK ow are the most significant molecular parameters affecting PFAS removal. • Membrane intrinsic structural characteristics affect the PFAS removal significantly. • Adsorption and rejection of PFAS may occur via similar driving forces. Although nanofiltration (NF) has been widely reported for removing long-chain per- and polyfluoroalkyl substances (PFAS) from water, little is known about the correlations between removal efficacy and PFAS/membrane characteristics, especially for emerging PFAS with shorter polyfluoroalkyl chain or containing fluoroether moieties. A systematic study of treatment of structurally diverse PFAS by NF can help predict the behavior of more unknown compounds during NF process. In this study, we conducted filtration experiments with five commercial NF membranes. Results show that seven legacy PFAS, three emerging perfluoroalkyl ether acids (PFEA) and two fluorotelomer sulfonates (FTS) can be removed simultaneously during the NF process, with rejection ranging from 66.0% to > 99.9%. The removal efficiency of five membranes decreased successively as DK > NF90 > XN45 > NF270 > DL. Rejection of FTS and PFEA by DK membranes were 88.3% to 97.1% and 81.7% to > 99.9%, respectively. Correlation analysis revealed that PFAS molecular structure and membrane characteristics significantly affect PFAS rejection. PFAS molecular weight (MW) and hydrophobicity (logK ow) and membrane intrinsic structural characteristics (e.g., molecular weight cut-off (MWCO), water permeability, and salt selectivity) are among the most significant parameters impacting PFAS removal. The findings imply that both steric hindrance and hydrophobic interactions contribute to PFAS rejection. Moreover, the mass of PFAS adsorbed on the membrane was positively correlated with their molecular parameters (i.e., MW and logK ow) and weakly correlated with membrane properties, suggesting that the adsorption and rejection of PFAS have similar driving forces. This study provides critical insights into the application of NF for emerging PFAS removal for both the scientific community and private industry, concerning water purification processes and remediation of thousands of PFAS-impacted sites. [ABSTRACT FROM AUTHOR]

[Display omitted] • Perovskite oxide LaMO 3-δ cathodes were applied for NO 3 –-N electroreduction. • La 2 CuO 4 exhibited best catalytic performance as its super electrochemical property. • The selectivity of NH 4 +-N and N 2 were 82.4 ± 2.2% and 9.4 ± 2.4%, respectively. • Both electron- and H*-mediated pathway occurred for NO 3 –-N electroreduction. • Oxygen vacancies and redox cycle of Cu(I)-Cu(II)-Cu(I) worked for NO 3 –-N reduction. Electroreduction removal of nitrate (NO 3 –-N) is considered as a promising approach to solve its adverse effects on environment and human health, where efficient and cheap catalysts are required. Perovskite-based catalysts showed a versatile catalytic ability for wide range of redox reactions, but seldom applied for NO 3 –-N reduction. Herein, four perovskite oxide cathodes, LaMO 3-δ (M = Fe, Co, Ni and Cu) were prepared and used for the reduction of NO 3 –-N. The Ruddlesden-Popper (RP) type La 2 CuO 4 exhibited the best NO 3 –-N catalytic activity among the four perovskite oxide cathodes, with a removal rate of 11.7 × 10-3 min−1. The high selectivity of NH 4 +-N (82.4 ± 2.2%) indicated that NH 4 +-N was the main final product for NO 3 –-N electroreduction at La 2 CuO 4 cathode, but 100% of N 2 selectivity could be obtained with addition of 1000 and 1500 mg/L Cl- as the electro-assisted chlorination process. The mechanism of NO 3 –-N electroreduction occurred by both electron- and H*-mediated pathway, and the oxygen vacancies and redox cycle of Cu(I)-Cu(II)-Cu(I) were proposed as the accommodation sties and direct electron sources for NO 3 –-N reduction. Generally, this study opens a novel avenue for the development of earth-abundant, cost-effective catalyst with effective NO 3 –-N electroreduction. [ABSTRACT FROM AUTHOR]

[Display omitted] • The device shows a steam generation rate of 1.73 kg·m−2·h−1 under 1 sun illumination. • Rh B and cyclohexane remaining can be removed after steam generation. • The non-wetting fabric has stability and universality in oil/water separation. • The device has the performance of salt-resistance. Freshwater has become a rare resource on account of population increase and environmental pollution. At present, most the solar-driven interfacial evaporators used for water polluted by organic solvents and dyes have an outstanding nature of clean water production due to their special design. However, its downside is that contaminants remaining in the residual polluted water cannot be removed. Herein, a device applied to water polluted by organic solvents and dyes is formed by a hydrogel-based interfacial evaporator (PVA hydrogel/CNTs) and non-wetting fabric. The photodegradation efficiency of the non-wetting fabric is 95.7% for Rh B dye after five cycles. Meanwhile, the organic solvents including toluene, cyclohexane and so on are cleared through the non-wetting fabric. Importantly, the device presents a clean water production rate of 1.73 kg·m−2·h−1 under 1 sun illumination and it has a freshwater produce rate of 1.63 kg·m−2·h−1 after 6 h of desalination experiments. Furthermore, the device displays the performance of salt resistance in a 3 h NaCl dissolution experiment. A new strategy is provided for interfacial water evaporation technology used for water dyed by organic solvents and dyes purification and has a great application potential. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pressure-time curves were classified according to curve shape and mechanisms. • New constant-flux RO pressure–time model was developed: the Integrated SDC Model. • Integrated SDC Model showed better fitting performance than previous models. • The proposed model could indicate the fouling tendency of a full-scale RO system. • Integrated SDC Model could predict pressure growth of RO systems in NEWater plant. Reverse osmosis membranes have been used to produce high-quality reclaimed water for portable and industrial use, but face inevitable fouling problems. In the constant flux RO membrane operation, fouling is manifested as increase in operational pressure. However, the pressure–time curves have no consistent form, and there's a lack of pressure–time models that is capable of fitting various shapes of curves. In this study, the pressure–time curves of RO membranes were summarized into 3 types according to their change in pressure increasing rate. Each type of curve was speculated to be caused by a specific density change pattern of the fouling layer. An Integrated Spherical Diffusion Cell (SDC) Model was developed for the pressure–time relationships of Type I curves (pressure increasing rate increases with time) and Type III curves (pressure increasing rate decreases with time). Time-course pressure data of Type I and III curves were collected from literature, and the Integrated SDC model fitted these data better than other models derived from literature. Over 70% of R2 exceeded 0.90 for Type I curves and over 85% of R2 exceeded 0.88 for Type III curves. Furthermore, the Integrated SDC Model also showed superior fitting performance to the operational data of the full-scale RO system in the Changi NEWater plant. The model could characterize the fouling tendency by the model parameters, and predict subsequent pressure growth with the pressure data within 20% increase compared to the original pressure. For 10 out of 14 sets of data, the relative error of the predicted final pressure to the actual final pressure was below 10%. The findings are well-applied to industrial practice and may enable further research in the pressure growth pattern of constant flux RO filtration, assuring stable operation of full-scale RO systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • MPA/LDH after absorption heavy metal could be converted to photocatalyst. • Adsorption efficiency and selectivity of MPA/LDH was enhanced via host–guest interaction. • Metal sulfides NPs were formed in the interlayer of LDH by in situ spontaneous reaction. • MPA/LDH could be used for the simultaneous removal of heavy metals and dyes. Adsorption is considered an effective way for the removal of heavy metal ions in aqueous solutions; however, recycling of spent adsorbents is a formidable challenge. We synthesized mercaptocarboxylic acid/layered double hydroxide (MPA/LDH) adsorbents for the removal of heavy metal ions from wastewater, and it demonstrated excellent adsorption capacities; the maximum adsorption capacities for Hg2+, Pb2+, and Cu2+ were 250.30, 122.10, and 105.33 mg/g at adsorbent dosage of 0.2 g/L and pH of 5.5. The excellent adsorption performance was attributed to the inner-sphere surface complexation between the heavy metal ions and the S-S and COO– groups in MPA/LDH. Moreover, host–guest interactions between MPA and the LDH laminate may have enhanced the adsorption efficiency and selectivity of MPA/LDH. After the adsorption of Hg2+, Pb2+, and Cu2+, highly dispersed metal sulfide NPs were spontaneously formed in the LDH interlayer via confined base catalysis, providing excellent photocatalytic activity for the degradation of organic dyes. High photocatalytic activity was attributed to the suitable energy band and high dispersity of metal sulfides. MPA/LDH-absorbed Hg2+ showed the best photodegradation performance of 99.2% for methylene blue. Notably, MPA/LDH can be used for the simultaneous removal of heavy metals and organic dyes under visible light irradiation. The findings of this study provide insights for developing an environmentally friendly method for conversion from adsorbent to photocatalyst, demonstrating wide prospects in industrial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • An excellent adsorbent EPMT was prepared from the expanded polystyrene waste. • Giving an upcycling strategy for the sustainable utilization of polystyrene foam. • EPMT showed outstanding stability under strong acid and ion interference. • The dyes were recovered in better purity. Single-use polystyrene impose an enormous environmental threat, but their recycling has been proven challenging. Chemical conversion is the most versatile and robust approach to combat polystyrene waste. Carbon materials adsorbent EPMT was prepared from expanded polystyrene waste and applied to recover Eriochrome Black T (EBT) and Congo red (CR) from aqueous solution. EPMT was characterized by different analytical skills and the outcomes were used to analyze the corresponding adsorption interactions. The maximum adsorption capacity of the adsorbent for EBT and CR were 560.25 and 1010.19 mg/g, respectively. Thermodynamic showed the adsorption was subject to an endothermic spontaneous process. In terms of reusability, the performance of adsorbent was kept in a superior state all the time, and the dyes were recovered in better purity. The adsorbent displayed outstanding elimination competence and realized the separation of different dyes when it was used as padding to equip packed column. In brief, converting waste polystyrene to an adsorbent offers potential for water purification and provides a new route for upcycling of polystyrene into value-added materials. [ABSTRACT FROM AUTHOR]

• AFIL organic solution was developed for CO 2 capture. • The regeneration energy was 2.98 GJ·t−1 CO 2 and 21.6% lower than that of MEA aqueous solution. • The relationship between k 2 and temperature was expressed as k 2 = 5.6192 × 10 8 exp - 3111.6 T . • The dominant role of mass transfer resistance gradually changed from gas phase to liquid phase. The main disadvantage of commercial absorption solution for CO 2 capture from flue gas is extensive energy consumption. A novel amino-functionalized ionic liquid (AFIL) organic solution of tetraethylene pentamine 2-methylimidazolium/N-propanol/ethylene glycol ([TEPAH][2-MI]/NPA/EG) is considered as a promising candidate absorption system because of its efficient CO 2 capture performance and low energy consumption. The thermodynamics and kinetics studies are very essential for evaluating the absorbent and its potential of future practical industrial application. In this work, the performance in these two aspects of [TEPAH][2-MI]/NPA/EG solution were investigated. The regeneration energy consumption was 2.98 GJ·t−1 CO 2 , which was 21.6% lower than that of benchmark monoethanolamine (MEA) aqueous solution, and the energy saving advantage was embodied in sensible heat and latent heat. Kinetic analysis showed that chemical reaction of CO 2 absorption into [TEPAH][2-MI]/NPA/EG solution took place in the pseudo-first-order reaction. The reaction rate constant and enhancement factor increased with the increase of absorption temperature, while those showed a decreasing trend with the increase of absorption loading. The relation between the second-order rate constant and temperature was expressed as k 2 = 5.6192 × 10 8 exp - 3111.6 T , and the activation energy was further calculated as 25.87 kJ·mol−1. Compared with those of MEA and several traditional ionic liquid solutions, these parameters indicated a stronger reaction ability of the novel system. Moreover, the mass transfer resistance of gas and liquid phase changed constantly during the absorption process, and the dominant role of mass transfer resistance gradually changed from the gas phase to liquid phase. The thermodynamics and kinetics of CO 2 capture revealed that the [TEPAH][2-MI]/NPA/EG solution had an excellent application potential in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • A heterogeneous catalytic system of NaBiO 3 for PMS without light irradiation was investigated. • Both radical (SO 4 −• and •OH) and non-radical (1O 2) were contributed to BPAF degradation. • The contribution rate of 1O 2 , · SO- 4, and · OH was calculated as 80.4%, 8.7%, and 9.9%, respectively. It has been shown previously that the NaBiO 3 (NBO) could efficiently photocatalytically degrade organic contaminants because of its excellent photocatalytic property. In this study, we proposed a heterogeneous catalytic system of NBO for peroxymonosulfate (PMS) without light irradiation. The results showed that NBO/PMS exhibited excellent performance toward bisphenol AF (BPAF) degradation and mineralization. The effectiveness of the NBO/PMS system was also investigated in different multicomponent systems. The effects of initial pH, NBO dosages, and PMS concentration for BPAF degradation were also investigated. Radical quenching experiments combined with electron spin resonance analysis indicated that singlet oxygen (1O 2) was the main reactive oxygen species, and · SO 4 - and · OH– radicals participated in the process. X-ray photoelectron spectroscopy revealed the main catalytic mechanism: lattice oxygen (O vac) was extruded during the transformation of Bi(V) to Bi(III) to form and activate oxygen (O*), and the generated O* between the [BiO 6 ] regular octahedral layers reacted with PMS on the NBO surface to form 1O 2. Based on the results of the Bi element, it is suggested that the activation process proceeded through electron transfer from NBO to PMS. The stability of NBO and applicability of the NBO/PMS system in a natural water environment were explored. This work provides a novel approach to PMS activation and the potential use of NBO for the decontamination of organic pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ZnFe 2 O 4 /AgBr brings high magnetic field effect. • The introduction of magnetic field can further improve the transfer of carriers. • ZnFe 2 O 4 /AgBr with negative MR shows high photocatalytic activity under magnetic field. • ZnFe 2 O 4 /AgBr has high adsorption capacity and efficient magnetic separation. A ZnFe 2 O 4 /AgBr magnetic photocatalyst was constructed to simply the structure of the Z-scheme photocatalyst, and further enhance the photocatalytic activity using the magnetoresistance (MR) effect of the system and an external magnetic field. The photocurrent density of ZnFe 2 O 4 /AgBr was 75.1 μA/cm2, which was higher than that of pure ZnFe 2 O 4 (47.6 μA/cm2). Whereas the photocurrent density of pure ZnFe 2 O 4 did not notably change under a magnetic field, that of ZnFe 2 O 4 /AgBr clearly increased to 151.8 μA/cm2 under a magnetic field of 1000 Oe. The MR results demonstrated that ZnFe 2 O 4 /AgBr had a more negative MR than ZnFe 2 O 4 did, therefore, the transfer of photogenerated carriers for ZnFe 2 O 4 /AgBr was quicker under the magnetic field. The existence of this magnetic field-enhanced effect can replace the role of the electron transfer bridge, and simply the Z-scheme structure. In addition, the photodegradation activity of ZnFe 2 O 4 /AgBr for organic pollutants also got obvious enhancement under the magnetic field. [ABSTRACT FROM AUTHOR]

[Display omitted] • APVC membrane had uniform macroporous surface structure and thin top skin layer. • The grafted TETA participated in the IP process in a synergistic manner. • Covalent bond between the support layer and the active layer was formed. • Semi-free-standing like structure of PA/APVC membrane overcame trade-off effect. • NF-6 membrane had expected interfacial stability in inverse permeation test. In this research, a novel interfacial enhanced thin film composite nanofiltration (TFC NF) membrane with nail-fixed like surface structure and wave line like cross-section structure, good permeability and superior interfacial stability was prepared by interfacial polymerization (IP) on one-step in-situ aminated polyvinyl chloride (APVC) support layer. The effects of amination agent (triethylenetetramine, TETA) content on the support layers and the effects of the support layers with different degrees of amination on the performance of the TFC NF membranes were studied comprehensively. Furthermore, the interfacial bonding strength of the TFC NF membrane was explored by the inverse permeation test. It was concluded from the results that higher TETA content in casting solution led to the APVC membrane to form macroporous surface structure, thinner top skin layer and larger mean pore size. Meanwhile, more TETA molecules were grafted onto the PVC chains through nucleophilic substitution to participate in IP in a synergistic manner. Accordingly, the corresponding TFC NF membrane formed a nail-fixed like surface structure similar to semi-free-standing polyamide (PA) layer and wave line like cross-section structure with thinner and denser active layer. The water flux of the TFC NF membrane prepared with the optimized APVC membrane as the substrate membrane was increased by 395% at 0.6 MPa compared with the TFC NF membrane prepared with PVC membrane as the substrate membrane, while Na 2 SO 4 rejection did not sacrifice and increased by 3.48%, which manifested that unique structure was favorable to speed up the water transmission and effectively conquered the trade-off effect. Moreover, the representative TFC NF membrane prepared with optimized APVC membrane as the substrate membrane with strong covalent bond between support layer and active layer demonstrated superior interfacial stability in the short-term circulating inverse permeation test. [ABSTRACT FROM AUTHOR]

• Poly (butyl acrylamide-co-divinylbenzene) nanofiltration membrane was synthesized. • The toplayer regularly distributed oxygen and nitrogen groups to anchor metal ions. • Fe-binding treatment enhanced the permeance and dye rejection in organic solvents. • Changes of the void size and the charge density in the toplayer were disclosed. A new nanofiltration composite membrane poly (butyl acrylamide-co-divinylbenzene) (poly-TaDb) was synthesized via a facile photopolymerization on polyetherimide using the monomers of n- tert -butyl acrylamide and divinylbenzene, and evaluated the separation performance in organic solutions. The unique poly-TaDb toplayer has a feature of branch structure containing regularly distributed oxygen and nitrogen groups that work as the interacting sites with metal ions (Fe3+, Zn2+, and Cu2+), as reflected by the characterizations of ATR-FTIR, XPS, AFM, etc. Without the metal ion treatment, the optimal poly-TaDb membrane shows the permeance of 31, 17, 20.4 L m−2h−1 MPa−1 respectively for organic solutions of tetrahydrofuran (THF), methanol (MeOH) and acetonitrile (ACN), with the rejection rates higher than 90% toward EB dye (879.8 g.mol−1). After interacting with these metal ions, the obtained Fe-binding poly-TaDb membranes possess higher permeance, with the THF, MeOH, and ACN permeance enhanced respectively to 113, 35, and 24.2 L m−2h−1 MPa−1, meanwhile maintaining high dye rejection rate. While the Cu- and Zn-binding membranes show much higher permeance but lower dye rejection rate. Density functional theory (DFT) calculations disclose that the void size of the toplayer network increases in the order of: the pristine (11.40 Å) < Fe-binding (11.54 Å) < Zn-binding (11.60 Å) < Cu-binding membrane (11.63 Å). It is the suitable void size and charge density distribution in the toplayer network of Fe-binding membrane. that results in the superior nanofiltration performance. This work provides a facile route to explore new polymeric network materials for highly effective separation performance in organic solvents. [ABSTRACT FROM AUTHOR]

• The high-salinity UF permeate of landfill leachate was concentrated efficiently by ED. • The conductivity of the ED concentrate can reach to > 120 mS/cm. • The COD and salt reduction ratio were 12.5% and 79.9%, respectively. • ED is stable for treating the UF permeate in the lab-scale and pilot-scale application. The treatment of landfill leachate, which is highly polluted wastewater, is a critical challenge for waste-to-energy power plants in China. In recent years, pressure-driven membrane processes such as ultrafiltration (UF), nanofiltration (NF), reverse osmosis (RO), and disk-tube reverse osmosis (DTRO) have been used to treat landfill leachate for water recovery. However, the water recovery ratio is relatively low because of the high osmotic pressure of the concentrated landfill leachate, and the treatment of DTRO concentrate is still a key issue. In this study, electrodialysis (ED), an electro-driven membrane process, was integrated into the current pressure-driven membrane processes to separate and concentrate the UF permeate. The results indicate that the optimal ion exchange membranes for assembly in the ED stack are the CJMC-2S/CJMA-2S membranes, and the voltage drop of the membrane stack was optimised to achieve a feasible voltage across the cell pair (0.5–0.6 V), as well as low specific energy consumption; the flow velocity of the dilute solution and concentrate was optimised at 4 cm/s. The conductivity of the ED concentrate could reach a value as high as > 120 mS/cm when the volume ratio of the initial concentrate to the dilute solution was 1:20, where the specific energy consumption was 3.76 kWh/m3. The chemical oxygen demand (COD) and salt reduction ratios were 12.5% and 79.9%, respectively. Additionally, the ED operating process was stable in ten-batch lab-scale operation and continuous pilot-scale application for the treatment of the UF permeate of landfill leachate. Hence, the ED process exhibits excellent performance and can be potentially integrated into the current method for treating landfill leachate. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel AFIL organic solution was proposed for CO 2 capture. • The novel AFIL organic solution has obvious advantage in the recyclability and viscosity. • The regeneration energy was 2.30 GJ·t−1 CO 2 and 39.5% lower than that of MEA/water. • The reaction mechanism of [TEPAH][AICA]/NPA/EG solution was comprehensively elucidated. A novel sustainable amino functionalized ionic liquid (AFIL) organic solution of tetraethylene pentamine 5-amino-4-imidazolecarboxamide/n-propanol/ethylene glycol ([TEPAH][AICA]/NPA/EG) was proposed for CO 2 capture to reduce the regeneration energy consumption. The solution had an efficient absorption loading of 1.78 mol·mol−1, and it still maintained a good recyclability after 10 cycles (regeneration efficiency > 88%). Under this condition, the regeneration energy consumption was 2.30 GJ·t−1 CO 2 , which was 39.5% lower than that of MEA/water. The absorption and desorption mechanisms were investigated by 13C NMR. For CO 2 absorption reaction, N atom of [AICA]− combined with CO 2 to form the carbamate directly, while other amino groups followed the zwitterion formation and deprotonation. Then some carbamates combined with alcohol to form the alkyl carbonates. For CO 2 desorption reaction, both the alkyl carbonates and carbamates combined with AFILH+ to decompose, but the alkyl carbonates decomposed completely and a small amount of carbamates remained, indicating that carbonate was easier to decompose than carbamate. The novel [TEPAH][AICA]/NPA/EG solution with low energy consumption and good recyclability, which provides a sustainable strategy for advancing carbon capture technologies. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new strategy in the study is proposed for preparing PPS membrane. • This process was simple and required fewer organic solvents. • The prepared PPS membrane had good hydrophobicity and chemical stability. • The PPS membrane can efficiently separate surfactant-stabilized water–oil emulsion. Polyphenylene sulfide (PPS) has excellent hydrophobicity and stability, making it an ideal material for preparing water-in-oil separation membranes. PPS membranes are mainly fabricated via thermally induced phase separation which requires a certain amount of solvent. The electrospinning technique is relatively simple and requires little solvent, and it has become a research hotspot in recent years. This study proposes a new strategy for preparing a PPS membrane for water-in-oil emulsion separation in harsh environments. Here, we prepared PPS composite nanofiber membranes via electrospinning and sintering technology. The membrane was formed using polyvinyl alcohol (PVA) as the sacrificial template and polyacrylonitrile as the supporting substrate. By studying the effects of the PPS/PVA mass ratio and sintering temperature on the PPS composite nanofiber membrane structure and performance, the optimum PPS membrane was selected for subsequent water-in-oil emulsion separation. The results show that the water contact angle of the PPS membrane was above 150°; the maximum pure oil flux was 1707 L/ (m2 h) for the surfactant-stabilized water-in-oil emulsion separation under gravity; and the separation efficiency was around 99%. Moreover, the membrane maintained good chemical resistance after immersion in an organic mixed or acid-base solutions for 5 days. [ABSTRACT FROM AUTHOR]