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• Near-infrared responsive photocatalytic nanofiltration membrane was fabricated. • It was used for continuous dynamic removing antibiotics in sewage effluent. • Self-cleaning foulant attachment on the activated membrane was analyzed. • Antibiotics were inclined to adhere to the background matrices than membrane. • It exhibited a powerful environmental risk reduction capability. Bifunctional photocatalytic nanofiltration (PNF) membrane has become a reliable frontier technique for removing refractory organic micropollutants. However, the active mitigated fouling mechanism from the microscopic perspective during its long-term operation of purifying real micro-polluted water is rarely studied. Herein, with an integrated use of QSense Explorer and confocal laser scanning microscope techniques, self-cleaning foulant attachment on an activated and customized near-infrared responsive polymeric PNF (termed as nPNF) membrane with good service performance for continuous dynamic removing antibiotics in sewage effluent environment was firstly elucidated. Time-dependent changes in dissipation oscillation frequency, sensed mass and the visualized foulant spatial distribution all indicated that there were only sporadic foulant attachment, an extremely low fouling layer thickness and irreversible fouling rate on/of the activated nPNF membrane top surface, thereby endowing it with excellent self-cleaning characteristic. This is probably because the reactive oxygen species (mainly •O 2 − and •OH) concurrently destroys the integrity of fouling layer and its internal adhesion structure, transforming part of the irreversible fouling on nPNF membrane surface into reversible one that is easy to wash off. These new horizons provided useful insight on the fate of selected antibiotics in the to-be-removed stage and self-cleaning foulant attachment of PNF membrane. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper aims to validate the feasibility of hairwork dyeing effluent (HDE) reclamation using an ultrafiltration (UF)-reverse osmosis (RO) integrated membrane system combined with coagulation-flocculation and sedimentation acquiring the highest possible product water recovery rate along with both satisfactory separation performance and well controlled membrane fouling. Under the circumstance of only physical cleaning involved, the laboratory-scale test yielded a higher and satisfactory reuse ratio of 76% for HDE, and the corresponding RO product as reclaimed water contained only 223 mg·L−1 of TDS, 3.87 mg·mL−1 of DOC and 10.3 mg·mL−1 of total hardness, which was obviously better than the quality of existing feedwater in hairwork dyeing process. After each processing unit, the distributions of fulvic (region III) and humic (region V) organics decreased continuously, while an overall rising trend in distribution of protein-like organics (regions I and II) was observed. Contact angle for the fouled UF and RO membranes significantly increased by 19.5° and decreased by 19.7°, respectively, which suggested that different polarity of organic or inorganic adsorption rather than membrane roughness was the main factors affecting wetting properties of the fouled employed membranes. Both ATR-FTIR and XPS spectra indicated that organic fouling on UF membrane surface under harsh condition (R UF = 90%) was mild and tolerable, whereas a surprising amount of hydrophilic micromolecular organics riched in carboxyl and hydroxyl functional groups were absorbed on RO membrane surface after permeation. Unlabelled Image • The feasibility of CFS-UF-RO processes for HDE reclamation was firstly studied. • This test yielded a higher and satisfactory reuse ratio of 76% for HDE. • Removal effect of COD and TOC by RO unit was contrasted with UF module. • Contact angle for the fouled UF and RO membranes appeared an opposite trend. • Organic fouling on UF membrane surface was mild and tolerable at R UF = 90%. [ABSTRACT FROM AUTHOR]

Abstract As a new type of green solvents, deep eutectic solvents (DESs) are attracting more and more attentions due to their unique properties and cheapness. However, most DESs reported previously were hydrophilic and thus limiting their applications in aqueous medium. In this study, a novel hydrophobic DES was prepared by mixing ethylparaben and methyl trioctyl ammonium chloride, and density, viscosity, and contact angle of the DES were determined to character its solvent characteristics. Then, this DES was used as an efficient additive of sol-gel sorbent coating of poly(dimethylsiloxane) (PDMS) fiber. It was found that the addition of hydrophobic DES could generate a lot of neat pores in the PDMS fiber surface, thus significantly improving the performance of PDMS fiber coating. The feasibility of PDMS-DES adopted for head space solid phase microextraction was evaluated by GC-FID for the extraction and determination of volatile organic compounds, such as toluene, ethylbenzene and o -xylene. Key parameters affecting the extraction efficiency were investigated systematically. Under optimal conditions, the linear range with PDMS-DES fiber lied between 10 and 1000 μg L−1, and the limit of detection (LOD) was in the range from 0.005 to 0.025 μg L−1. Compared with homemade PDMS fiber, the peak area of signal response for the PDMS-DES fiber was 3 times higher. At the same time, the LOD for the proposed method was much lower than the commercial 100 µm-PDMS fiber coating. Graphical abstract fx1 Highlights • A novel hydrophobic DES mediated sol-gel SPME coating has been developed. • Effective extraction depends on the extraction ability of DES and pore formation. • The signal response is 3 times higher than that with traditional PDMS fiber coating. [ABSTRACT FROM AUTHOR]

Highlights • Novel nanofiltration membranes were fabricated with tunable surface charges. • PCSs with modulated substituted degree of phosphate group were synthesized. • FTIR and EDX analysis verified that it was introduced into the NFMs. • Impacts on NFMs’ permeation and selectivity performance were studied. • NFM4 exhibits good chemical stability in the long-term operation. Abstract Phosphorylated chitosan (PCS) with tailored amount of phosphate groups was synthesized, and novel composite nanofiltration membranes (NFMs) with tunable surface charges were prepared by coating PCS onto polyacrylonitrile (PAN) supporting layer and subsequently cross-linked by glutaraldehyde (GA). Chemical structures and compositions of PCS and NFMs, along with morphologies, surface charges, and performance of NFMs were represented by using FTIR, TG, ATR-IR, SEM-EDX, AFM, streaming potential analyzer, and cross-flow flat permeation test, respectively. The effect of different phosphorous abundance of PCS precursors on the surface charge and permselectivity of NFMs was investigated systematically. It was illustrated that the incorporation of phosphate group with high-substitute degree did enhance the surface charge and selectivity of NFM, respectively, while retaining its permeability. The resultant membrane showed a zeta potential of −77.6 mV at 1 mol·m−3 KCl electrolyte solution and pH 7.0, significantly more superior than that of the commercial DL membrane. For the feedwater (Na 2 SO 4 + MgCl 2 , 1.0 g·L−1), the mass ratio of SO 4 2−/Cl− and Mg2+/Na+ decreased from initial 0.5:1 in the feed to 1.58 × 10−2 and 0.254 in the permeate after filtration by the optimal NF membrane. Anionic dyes removal tests also confirmed the existence of negative charge characteristics from the prepared membranes, and pivotal role of the Donnan exclusion in separating performance. In addition, NFM4 exhibits good chemical stability in the long-term operation. [ABSTRACT FROM AUTHOR]

Based on the continuous innovation of membrane materials and partnered reagents, it is necessary to timely evaluate the efficiency improvement of a package of relevant wastewater treatment processes and clarify the associated pivotal causes. For this purpose, the root-cause analysis for fouling mitigation derived from influent characteristics, the techno-economic and toxicity reduction assessments of hairwork dyeing effluent (HDE) reclamation via three membrane-based hybrid systems approaching zero discharge were systematically carried out. The experimental results showed that with the aid of a novel efficient and biodegradable flocculant, the lower fluorescence peak intensity, the more negative zeta potential and the quantitatively dominant hydrophobic components in feedwater all helped to mitigate the same-charged hydrophilic TFN-CQDs membrane fouling due to modification of itself. Accordingly, the optimal processing technology required the minimum amount and replacement frequency for membrane elements and less than 1/5 and 1/10 of the energy consumption and chemicals of their counterparts, respectively. Besides, it also decreased the waste (brine) stream volume fraction to 7%, and greatly increased B/C value of supernatant to 0.667, thus strengthening "intermediate control" of pollutants. Although the organic contaminant components in HDE basically transcend the aromatic/hydrophilic differences in producing biotoxicity, all schemes still had good performance in its elimination. Undoubtedly, the outcome of these evaluations will provide valuable technical guidance for scaling-up the prototype results and promoting the cleaner production of local wig enterprises. [Display omitted] • The techno-economy of hairwork dyeing effluent reclamation was assessed. • Customized flocculant and nanocomposite membrane incorporated in Scheme III. • Scheme III achieved better control of the source and intermediate of pollutants. • Fouling mitigation, biotoxicity elimination assessments were also fulfilled. • It will promote the clean production of local wig enterprises. [ABSTRACT FROM AUTHOR]

Based on the fact that when inlet bulk solution with low or medium concentration was involved, scaling was apt to appear on nanofiltration (NF) membrane surface in retentate side. Therefore, study on its surface charge performance under threshold concentration condition is necessary. Two polyamide composite NF membranes (DL and DK) were characterized with streaming potential ( E s ), zeta ( ξ ) potential and other measurements encountering with a wide ionic strength range (1.5–108 mol·m −3 ). Then, the interactional relations between membrane surface charge and concentration polarization ( CP ) degree, along with the relevant constituting factors were investigated. The results showed that even when the sparingly soluble salt concentration for CaSO 4 exceeded its threshold point, both NF membranes at pressure drop of 180 kPa still exhibited low and medium-intensity surface electrokinetic phenomena (−5.94 ≤  E s  ≤ −3.41 mV; −38.82 ≤  ξ -potential ≤ −36.34 mV). It turned out that solvent flux decreased almost linearly, but measured concentrations of the scalant ions in NF retentate streams increased slightly at first and then rapidly with the enlargement of ξ -potential, respectively. Meanwhile, mass transfer coefficient and boundary layer thickness had a negligible change in the scope of testing ξ -potential. Therefore, CP SO4 2− and CP Ca 2+ decreased apparently with ξ -potential becoming less negative for the adopted NF membranes. [ABSTRACT FROM AUTHOR]

• A novel surface-anchored photocatalytic nanofiltration membrane was fabricated. • A continuous flow-through process under visible light irradiation was involved. • It removes antibiotics in sewage effluent indiscriminately to more than 99%. • Good self-cleaning and biotoxicity reduction capacities were also fulfilled. • The usability of photocatalytic nanofiltration membrane is greatly improved. Bifunctional photocatalytic nanofiltration (PNF) membrane is increasingly concerned in practical micro-polluted water purification, but there are still several bottlenecks that inhibit its practicality. In this context, the feasibility of a novel metal-free and visible light-responsive surface-anchored PNF membrane for simultaneously removing target antibiotics in real sewage effluent in a continuous dynamic process was explored. The results showed that the optimal PNF-4 membrane was expectedly consisted of an inside tight sub-nanopore structured separation layer and an outside thinner, smoother, super hydrophilic mesoporous degradation layer, respectively. Consequently, the activated PNF-4 membrane could synergistically reduce trimethoprim and sulfamethoxazole concentrations to below two orders of magnitude, accompanying with almost constant high water permeability, suggesting that the hydrophilic modification of the mesoporous degradation layer basically offsets its inherent hydraulic resistance. Also, after repeating the fouling-physical rinsing process three times lasted for 78 h, only sporadic adherent contaminants remained onto the top surface, together with the minimal total and irreversible fouling ratios (as low as 7.2% and 1.2%, respectively), strongly demonstrated that PNF-4 membrane displayed good self-cleaning performance. Undoubtedly, this will significantly reduce its potential cleaning frequency and maintenance cost in long-term operation. Meanwhile, the acute and chronic biotoxicities of its permeate to Virbrio qinghaiensis sp. -67 were also reduced sharply to 2.22% and 0.45%, respectively. All of these evidences suggest that the dual functions of PNF-4 membrane are synergetic in an uninterrupted permeating process. It will provide useful insights for continuously enhancing the practicality and effectiveness of PNF membrane in actual micro-polluted water purification scenarios. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, one brackish water quality, which typically represented the water quality in the Huanghuai region of China, was simulated and used as feedwater to run an ultrafiltration (UF)–nanofiltration (NF) integrated membrane system. Laboratory-scale experiments were carried out to evaluate NF softening performance. The influences of transmembrane pressure (0.6–2.2 MPa), inlet tangential flow velocity (0.087–0.384 m·s − 1 ) and feedwater temperature (7–35 °C) on the softening efficiencies of two NF membranes denoted as DK (termed as NF1) and DL (termed as NF2) were investigated. The experimental results revealed that the calculated total hardness and the bivalent ion (SO 4 2 − , CO 3 2 − , Mg 2 + and Ca 2 + ) concentrations in NF2 product water on the same operation were all slightly lower than those in NF1 permeate in two schemes. Additionally, pH value of NF permeate decreased prominently than those in feedwater with increasing of transmembrane pressure, inlet tangential flow velocity or decreasing of feedwater temperature within the testing scope. [ABSTRACT FROM AUTHOR]

This study explored the effect of increasing nanofiltration (NF) permeate recovery ( R NF ) by recirculation and dosage of chemicals on NF separation performance, concentration polarization ( CP ) and accumulation of scaling-prone ion concentration on NF membrane surface. The related coupling effect on seawater reverse osmosis (SWRO) desalination was also evaluated. The results show that when R NF for a single NF membrane element increased from 40% to 65%, pH of NF retentate and recycling ratio ( R r) increased from 5.02 and 0.75 to 5.10 and 3.58, respectively, with the dosage of both acid and antiscalant. In the same R NF range, the rejection of Ca 2 + , CO 3 2 − , SO 4 2 − , TDS and total hardness decreased from 35.1%, 78%, 96.3%, 18.2% and 56.1% to 28%, 76.9%, 96.1%, 10.9% and 33.9%, respectively, for NF in without chemical dosage. The CO 3 2 − and SO 4 2 − ion concentrations both in SWRO brine and on SWRO membrane surface were only around 0.12, 98, 0.12 and 99 mg·L − 1 , respectively, which were much lower than those in typical SWRO brine. Higher rejection for SO 4 2 − ion and higher selectivity of divalent ions over monovalent ions by the NF element were demonstrated in this study, which indicates that ESNA3 membrane yields a relatively higher efficiency of seawater pretreatment. [ABSTRACT FROM AUTHOR]

Abstract: Pilot-scale tests were carried out on a nanofiltration (NF)–seawater reverse osmosis (SWRO) integrated membrane system (IMS) using a kind of ultra-low pressure and high selectivity NF membrane (ESNA3, Hydranautics). Three different schemes were investigated for the NF seawater softening processes. The effect of increasing NF permeate recovery rate (R NF) on the potential of scaling in the NF and RO modules was investigated in term of concentration polarization modulus (CP) of scalant ions, Stiff and Davis Stability Index (S&DSI), and Supersaturation Index (SI) of CaCO3 and CaSO4. The results show that within the test range, high R NF, large permeate flux and low specific energy consumption (Es) could be achieved simultaneously for the loosen NF membrane. The Es for ESNA3 membrane could be lower than 0.95kWh·m−3. CP SO4 2− was larger than CP CO3 2− in the NF module under the NF retentate recycling operating conditions. The SI data indicated that at R NF of higher than 65% and with antiscalant addition and pH adjustment, CaSO4 would preferentially precipitate on NF membrane surface. However, with pH adjustment, the S&DSI values on the NF and SWRO membrane surface remained negative, which indicated that CaCO3 scaling could not form in the pilot test operating range. [Copyright &y& Elsevier]

Abstract: Pilot-scale experiments were carried out on a nanofiltration (NF)–seawater reverse osmosis (SWRO) integrated membrane system (IMS) to evaluate scaling potential on NF and SWRO membrane surface using a kind of loosen NF membrane and costal seawater. The effect of NF permeate recovery (R NF ) increasing on the occurrence of scaling in the NF and SWRO module was investigated in term of concentration polarization modulus (CP) of scalant ions, Stiff and Davis Stability Index (S&DSI), as well as Supersaturation Index (SI) of CaCO3 and CaSO4. The results show that the salt rejection by the loosen NF module is only about 10%, while the rejection of SO4 2− is higher than 95%; S&DSI is always less than zero, indicating that CaCO3 scaling could not form on the NF membrane surface when R NF was less than 35%. is much higher than ; and at R NF of higher than 30%, SI of CaSO4 on NF membrane surface increased gradually higher than 1.0, which indicated that CaSO4 scale is more apt to form on the NF membrane surface than CaCO3 at that NF permeate recovery. This scaling sequence in the loose NF module was different from that in traditional SWRO desalination processes. [Copyright &y& Elsevier]

• Fouling behavior evoked by PhACs under multiple influent matrices was assessed. • Both customized NF membrane and advanced pretreatment were involved. • Solute-membrane interactions were much weaker than solute-solute interactions. • The roles of critical factors on separation mechanism were re-recognized. • RQs of PhACs in virgin/fouled NF permeate showed low risk to aquatic organisms. Rare information is available on fouling behavior of customized nanofiltration (NF) membrane evoked by pharmaceutically active compounds (PhACs) under real multiple influent matrices pretreated by ultrafiltration module beforehand. To this end, a novel tight NF membrane with excellent perm-selectivity and antiadhesion was fabricated and used to assess its separation performance/mechanism and fouling behavior to a broad range of small molecular PhACs in the context. The adsorption ratio results revealed that the affinities between five selected PhACs and the customized nanocomposite membrane surface were all much weaker (below 5.5%) than the solute-solute interacting forces (between 23.6 and 83.2%), whether for natural or synthetic complex micropollutants. The predominant membrane fouling could be interpreted by the incomplete blocking model in the permeation of both influent conditions. For neat nanocomposite membrane, the order of critical factors important on separation mechanism was electrostatic effect, adsorption and steric hindrance. The fouling layer seemed to act as a secondary separating layer for those negatively charged or hydrophilic PhACs, but showed the cake enhanced concentration polarization effect for the neutral and hydrophobic ones. This study provides valuable insights for defining PhACs fate and NF membrane fouling behavior to fit increasingly stringent criteria for wastewater treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: An ultrafiltration–nanofiltration (UF–NF) integrated membrane system (IMS) was operated for 500h to examine the performance of the NF membrane in seawater desalination pretreatment. The rejection of divalent ions, TDS, TOC and UV254 by the NF membrane as well as the permeation flux decreased gradually with operating time before each chemical cleaning procedure, while the calculated Stiff and Davis Stability Index (S&DSI) increased gradually from negative up to positive. The result indicates that there exists inorganic fouling during the long run. However, the IMS produced excellent effluent with 93.6% removal of total organic carbon (TOC) for long-term operation. The TOC concentration of the NF permeation samples was in the range of 0.06–0.35mg/L. The chemical cleaning results indicated that inorganic fouling should be preferentially paid attention to, and a combination of citric acid cleaning and NaOH cleaning may achieve an optimal cleaning efficiency. The long-term operation reveals that the membrane is more prone to fouling gradually after chemical cleaning. [Copyright &y& Elsevier]

Abstract: Nanofiltration (NF) membranes are playing a more and more important role in brackish and seawater softening process, wastewater reclamation and other industrial separation. In this study, ultrafiltation (UF) and NF (ESNA3, Hydranautics) were assembled to an integrated membrane system (IMS) as pretreatment prior to seawater reverse osmosis (SWRO) to evaluate the NF efficiency of seawater softening. The influences of NF feed property (the feed from UF1 with 100kDa MWCO and UF2 with 20kDa MWCO, respectively), operating pressure (0.5–3.0MPa), cross-flow velocity (0.028–0.048m/s) and feed temperature (5–17°C) on the softening efficiency in terms of the NF flux and ion rejection were investigated. The results showed that the high softening efficiency of NF membrane could be achieved using UF membrane with smaller MWCO (20kDa). NF system using UF2 as pretreatment process yielded a higher flux of 61.4L/(m2 h) with Ca2+, Mg2+, SO4 2− rejection of 44.37%, 73.26% and 99.82%, respectively, under the optimum operating conditions of operating pressure at 1.5MPa, cross-flow velocity at 0.035m/s and feed temperature at 12.5°C. And, the relatively excellent selectivity of divalent ions and univalent ions can be obtained by ESNA3 membrane compared to that of other NF membranes reported in the literature, indicating that the ESNA3 membrane seems to be appropriate for seawater softening process. [Copyright &y& Elsevier]

A novel combination of custom-tailoring tight nanocomposite membrane process with dual-stage pretreatment incorporating flocculation and ultrafiltration has been experimentally conceived for the advanced reclamation of seriously contaminated hairwork dyeing effluent (HDE). The hybrid system exhibited impressive advantages of qualified recycle rate of HDE (91.2%) and minimal environmental impact when taking both bearable membrane fouling and appropriate long-term separation performance into consideration. It was observed that after partial alternative doping of M-tolidine-H and continuous incorporating of carbon quantum dots, both skin features (smoothness, hydrophilicity and charge) and nanoporous loose body (porosity and apparent pore size) of the resultant membranes were improved synergistically. As a consequence, the optimal TFN-CQDs membrane showed high water permeance of 4.31 L m−2 h−1 bar−1, rejection for small-sized organics (≥97.3%) and salt (≥96.4%) and good antifouling ability (86.2% of flux recovery ratio) operated for 72 h, which were superior than those of most other reported permeate membranes. Besides, the economical and feasible pretreatment steps including less dosage (only 100 mg L−1) of biodegradable CLF-10 flocculant and cheap UF module made the optimized reuse process more attractive. Overall, this study has taken a concrete step forward on the road of realizing zero liquid discharge and advanced reclamation of HDE. [Display omitted] • A tight nanocomposite membrane was tailored for advanced reclamation of HDE. • A qualified and stable R ov of HDE up to 91.2% was accomplished. • The optimal one showed excellent perm-selectivity and good antifouling ability. • Less dosage of biodegradable flocculant and minimizing retentate were involved. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effective fractionation of HDE was feasible by a novel loose NF membrane. • Partial alternative and continuous incorporating of BP and GQDs were involved. • TFN-0.2 membrane exhibited superior flux, dye rejection and salt permeation. • It showed good fouling resistance and stability for HDE treatment. The complete fractionating synthetic and real dye/salt mixtures through loose nanofiltration membranes are of great significance for the textile wastewater recycling and reuse. Therefore, in this paper, a custom-tailoring loose nanocomposite membrane was fabricated to validate the feasibility of high-efficient dye/salt fractionation in the real pretreated hairwork dyeing effluent (HDE). It was observed that after partial alternative doping of 4,4′-bipiperidine and continuous incorporating of graphene quantum dots, the resultant membrane skin-layer features including smoothness, hydrophilicity and surface charge as well as nominal pore size were improved synergistically. Consequently, the optimal TFN-0.2 membrane showed outstanding fractionation and antifouling performance for synthetic dye/salt mixtures and real pretreated HDE. Specifically, for the former, the as-prepared TFN-0.2 membrane displayed the highest water permeance of 56.0 L·m−2·h−1·bar−1, retention for all selected dyes (≥99.8%) and salt permeability (≥91.2%). Besides, the antifouling indexes in terms of reversible and irreversible fouling ratios of TFN-0.2 membrane against HDE solution reduced from 13.3% and 20.7% of pristine one to 8.32% and 1.34%, respectively. While flux recovery ratio markedly enhanced from 79.1% to 98.5% in the meantime. Overall, this work provides a facile method to fabricate high-efficient loose nanofiltration membranes for sustainably and precisely fractionating dye/salt mixtures from textile wastewater. [ABSTRACT FROM AUTHOR]

This present work validated the feasibility of high-efficient removal of series of cationic small-sized contaminants such as pharmaceutically active compounds (PhACs), dyes and hardness-forming ions in aqueous solution by novel thin-film nanocomposite (TFN) membranes. Thanks to the positively participated effect on interfacial polymerization for both nanostructured quaternized carbon-based nanoparticles (QCBNPs), skin-layer characteristics including smoothness, wettability and positive charge as well as nanoporous loose body (porosity, thickness) of the resultant TFN membranes were all markedly improved after doping modification. On this basis, compared with the neat thin-film composite membrane, these modified TFN membranes showed perfect mirror-symmetric transformation in the rejection orders of the selected electrolytes, dyes and PhACs with different charge properties, respectively. Of course, these changes were all accomplished in the process of increasing each small-sized contaminant removal rate, membrane permeability and fouling resistance. Specifically, the optimal TFN-QCQDs membrane possessed high permeate flux of 23.8 L m−2·h−1 bar−1, 99.7%, 99.5%, 98.9%, 98.4% and 95.7% rejection rates for cationic trimethoprim, atenolol, rhodamine B, methylene blue and MgCl 2 , flux recovery ratio of 85.5%, which increased by 53.6%, 6.75%, 5.96%, 2.17%, 2.21%, 17.0% and 29.6%, respectively, compared with the neat membrane. In brief, both QCBNPs embedded nanocomposite membranes provide good alternative options for efficient and sustainable removing series of cationic small-sized contaminants by one step. [Display omitted] • Efficient removal of two cationic PhACs, dyes, 2:1/2:2 electrolytes by one step. • Novel tight NF membranes were fabricated by doping nanostructured QCBNPs. • Mirror-symmetric changes in rejection orders for employed PhACs occurred. • Three related effects have been scientifically re-recognized and evaluated. [ABSTRACT FROM AUTHOR]

[Display omitted] • PHACUF-caused PA or PES NF membrane fouling mechanism was studied. • The roles of Mg2+ and Ca2+ from micro- and macro-level were analysed. • HOA and HON fractions possess higher hydrophobicity and content percentage. • Fewer Mg2+ ions could fully link with PHACUF molecules than Ca2+ ions. • The related membrane-foulant and foulant-foulant interactions were explored. It is of practical significance to explore the fouling mechanism of nanofiltration membrane caused by residual natural organics left over after ultrafiltration unit. This paper systematically investigates nanofiltration membrane fouling behaviors induced by preserved humic acid components after ultrafiltration filtration (PHACUF) in the existence of Mg2+/Ca2+ ion from micro- and macro-level analyses. Those similarities and disparities in the roles of polyethersulfone or polyamide active layer to these issues were also studied comparatively. The results showed that there existed unneglectable standard blocking for polyethersulfone membrane when permeating bare PHACUF solution. However, with the addition of divalent cations, the main fouling mechanism changed to intermediate blocking. Fewer Mg2+ ions could fully link with the carboxylic groups of PHACUF molecules, leading to larger and more dense flocs by the "bridging" effect and the aggravated nanofiltration membrane fouling with more compact layer structure, especially for more hydrophobic polyethersulfone membrane. It could be inferred that in Mg2+/Ca2+ environment, actually, PHACUF-caused nanofiltration membrane fouling was mainly formed and constituted by hydrophobic acids and neutral fractions with much higher both hydrophobicity and content percentage, whether for the membrane-foulant interaction in the early stage or the foulant-foulant interaction in subsequent permeation stage. [ABSTRACT FROM AUTHOR]

• The roles of Ca2+/Mg2+ in PHACUF induced NF fouling were deeply studied. • Hydrophobic in appearance for PHACUF with a higher charge density than HA. • Mg2+ was more effective than Ca2+ in intensifying PHACUF size and NF fouling. • O 1s bonding energy shift and ITC data also provided powerful evidences. This study was conducted to systematically investigate how Ca2+/Mg2+ interacted with the preserved humic acid components after UF filtration (PHACUF) to cause fouling of nanofiltration (NF) membrane. Inherent characteristics including molecular weight distribution, charge, wettability, hydrodynamic size of PHACUF and its fractions under predetermined conditions and differences in PHACUF-induced NF membrane fouling behaviors, surface characteristics in the absence/presence of Ca2+/Mg2+ were analysed and explored, respectively. Microinteraction forces between PHACUF and Ca2+/Mg2+ were also compared. The results manifested that contrary to many typical reports about HA foulant, Mg2+ exhibited superior charge screening effect with PHACUF, and performance in accelerating hydrodynamic colloid size, dense membrane fouling compared to Ca2+. O 1s bonding energy shift and ITC data provided powerful and quantified evidences that Mg2+ could coordinate with PHACUF more effectively and cause more serious fouling deposits on NF membrane surfaces than Ca2+, presumably due to its favorable specific charge and binding ability. In terms of its own components, HOA fraction seems destined to preferentially bond with most of Ca2+ and Mg2+ ions and constitute a high proportion of membrane fouling loading because it possesses the highest charge density and content compared with other fractions in near-actual natural surface water circumstance. [ABSTRACT FROM AUTHOR]

The purpose of this study is to prepare eco-friendly cationic tree-shaped cellulose-based flocculants (CLFs) through ultrasonic modification as the primary pretreatment, and then realize advanced hairwork dyeing effluent (HDE) reclamation by coupling with dual membrane process. The results showed that the optimal CLF-10 could be obtained by extra ultrasonic processing with a certain conservative time to tune its microstructure appearing in a well-veined and fluffy tree-shaped morphology with relatively uniform particle size distribution. The excellent flocculation performance of CLF-10 in terms of turbidity, total organic carbon (TOC) and dissolved organic carbon (DOC) removal rates reached up to 99.1%, 72.1% and 70.5% at the dosage of 100 mg L−1, and the largest and most dense flocs (A mean of 269 900 μm2 and D f of 1.80) were formed accordingly. This is precisely because the above mentioned microstructure properties enable it to have smaller steric hindrance effect and more active sites, thus effectively clustering the largest amount of target contaminants. Consequently, the bench-scale test employed CLF-10 agent achieved a higher HDE recovery rate of 80.3% under the circumstance of lower operating pressure and significantly mitigated membrane fouling, and the final cleaner reuse water only contained 76.2 mg⋅L−1 of total dissolved solids (TDS), 23.9 mg CaCO3·L−1 of total hardness and 1.85 mg·L−1 of DOC. Image 1 • Tree-shaped cellulose-based flocculants were modified through ultrasonic. • It appeared in a well-veined and fluffy morphology with relatively uniform PSD. • CLF-10 with the optimal flocculability led to the largest and most dense flocs. • Advanced reuse of HDE by coupling with dual membrane process was realized. • This test yielded a higher and satisfactory reuse ratio of 80.3% for HDE. [ABSTRACT FROM AUTHOR]

Sepsis-associated encephalopathy (SAE) is a severe complication that affects the central nervous system and is a leading cause of increased morbidity and mortality in intensive care units. Psoralidin (PSO), a coumarin compound isolated from the traditional Chinese medicine Psoralea corylifolia L. , can penetrate the blood-brain barrier and has various pharmacological activities, including anti-inflammation, anti-oxidation and anti-depression. This study aims to explore whether PSO alleviates SAE and delve into the underlying mechanisms. We found that PSO treatment significantly reduced sepsis scores, aspartate transaminase (AST) and aspartate transaminase (LDH), while increased anal temperature and neurological scores in CLP-injured mice. Moreover, PSO treatment ameliorated sepsis-associated cognitive impairment, mood, anxiety disorders, inhibited inflammatory responses, as well as attenuated endoplasmic reticulum stress (ERS). These results were also validated in vitro experiments, PSO treatment reduced ROS, inflammation response, and attenuated ERS in LPS-injured N2a cells. Importantly, tunicamycin (TUN), as ERS agonist, significantly reversed the protective effect of PSO on LPS-injured N2a cells, as evidenced by increased expression levels of IL-6, NLRP3, CHOP, and ATF6. Likewise, ATF6 overexpression also reversed the protective effect of PSO. In conclusion, these results confirmed that PSO has a protective effect on SAE, which was largely attributed to neuroinflammation and ERS. These findings provide new insights into the neuroprotective role of PSO and suggest that PSO is a new therapeutic intervention of SAE. [Display omitted] • Psoralidin treatment ameliorated sepsis-associated cognitive impairment, mood, anxiety disorders, inhibited inflammatory responses, as well as improved endoplasmic reticulum stress. • Tunicamycin, as endoplasmic reticulum stress agonist, significantly reversed the protective effect of psoralidin on LPS-injured N2a cells. • Psoralidin has a protective effect on sepsis-associated encephalopathy, which was largely attributed to neuroinflammation and endoplasmic reticulum stress. [ABSTRACT FROM AUTHOR]

• Several new hydrophobic deep eutectic solvents (DESs) were prepared • A high efficient microextraction method was developed based on hydrophobic DESs • Successfully used for the determination of bisphenols from food-contacted plastics • The proposed method was simple, efficient and environment-friendly As a new kind of green solvents for potential replacement of traditional volatile organic compounds, deep eutectic solvents (DESs) have been attracting more and more attention in various applications. In this work, three types of hydrophobic DESs were synthesized by simple mixing of trioctylmethyl ammonium chloride (used as hydrogen bond acceptor) with decanoic acid, ketoprofen and gemfibrozil (hydrogen bond donors), respectively, at different molar ratios. In order to evaluate the solvent characteristics of these DESs, some of the physical properties such as melting point, density, viscosity, and water contact angle were determined. Then, these hydrophobic DESs were used for the vortex-assisted liquid-liquid microextraction of bisphenol-type contaminants in water, followed by quantitative determination of bisphenols contents with high performance liquid chromatography (HPLC-FLD) coupled with fluorescence detection. For this purpose, four bisphenols, namely, 2, 2-bis(4-hydroxydiphenyl)propane (BPA), 2, 2-bis (4-hydroxyphenyl)butane (BPB), 4, 4′-(1-phenylethylidene)bisphenol (BPAP) and 4, 4′-cyclohexylidenebisphenol (BPZ) were selected as model contaminants. It was found that the enrichment factors of the proposed method were in the range from 97 to 112, depending on the structure of the analytes. Under optimal experimental conditions, the linearity ranges of the method varied from 0.3 to 700 µg L−1 with linear correlation coefficients (R2) higher than 0.996. The limit of detections (LODs) and limit of quantifications (LOQs) were in the range of 0.3-0.5 µg L−1 and 0.06-0.08 µg L−1, respectively. Furthermore, the developed method was successfully used in the extraction and determination of four bisphenols from food-contacted plastic samples. [ABSTRACT FROM AUTHOR]

• Several new hydrophobic deep eutectic solvents with low viscosity were prepared. • Higher efficient microextraction method based on hydrophobic DES was developed. • Successfully used for the determination of PEs in food-contacted plastics. • The proposed method was simple, rapid and environment-friendly. In this work, a novel class of eight low viscosity hydrophobic deep eutectic solvents (DESs) has been designed and prepared from two kinds of quaternary ammonium salts and six kinds of water-insoluble fatty alcohols/acids. Several physical properties of these DESs, such as melting point, density and viscosity, have been determined to investigate their adaptability as solvents. Then, such DESs are used as extraction solvents in a vortex-assisted liquid-liquid microextraction for the extraction and preconcentration of phthalate esters (PEs) from water samples, and the content of PEs from food-contacted plastics is then determined by using gas chromatography. It is found that the analytic method developed in this work exhibits wide linear range of 5–1000 µg L−1, and the limit of detections for target analytes is as low as 1 µg L−1. Finally, the proposed method has been successfully used for the determination of PEs from food-contacted plastics. [ABSTRACT FROM AUTHOR]

• S-TiO 2 was prepared by condensation reaction and doped in the S-TiO 2 /PVDF-g-PSSA PEM. • The fouling mechanism of PEM in MFC was studied by QCM-D with membrane-coated sensor. • The incorporation of S-TiO 2 improved the proton conductivity of composite membrane. • The composite membrane has superior antifouling ability than that of Nafion membrane. • The MFC with the S-TiO 2 /PVDF-g-PSSA had higher maximum power density and COD removal. Sulfonated titanium dioxide (S-TiO 2) was prepared by the grafting of sulfonic groups onto TiO 2 , and doped into the PVDF-g-PSSA as a highly efficient inorganic additive, thus achieving simultaneous improvement of the proton conductivity and anti-fouling property of the synthesized S-TiO 2 /PPSSA proton exchange membrane (PEM). The S-TiO 2 /PPSSA membrane was implemented in microbial fuel cell (MFC) for the first time, and its physicochemical properties and performance in MFC were studied. A new technique of combining Quartz crystal microbalance with dissipation with membrane spin-coated sensors made by a spin coating method was utilized to provide an insight into the anti-fouling property of the prepared membranes. The implementation of Fourier transform infrared spectrometry and X-ray photoelectron spectroscopy demonstrated TiO 2 was successfully introduced into the sulphonic groups. The S-TiO 2 /PPSSA-5.0 membrane has a significant increase in the water uptake (40.9%) and proton conductivity (0.067 S/cm) compared with the PVDF-g-PSSA membrane. QCM-D results indicated that it has better anti-fouling property than pristine membrane and Nafion 117. Moreover, the MFC with the S-TiO 2 /PPSSA-5.0 membrane exhibited a maximum power density of 130.54 mW/m2, very close to that of Nafion 117 (132.02 mW/m2), but had the highest COD removal of 91% and least bio-fouling adsorption. These results demonstrate that the blending of sulfonated organic polymers and sulfonated inorganic additives can improve the electrochemical and anti-fouling properties of the composite membranes, which is a new concept for the preparation of PEM suitable for MFC. The S-TiO 2 /PPSSA-5.0 composite PEM is an appropriate candidate separator for the large-scale application of MFCs. [ABSTRACT FROM AUTHOR]

A novel anti-fouling cation exchange membrane (CEM) of sulfonated polybenzimidazole (S-PBI) was fabricated by the polymer bulk grafting modification of poly (4,4′-diphenyl ether-5,5′-bibenzimidazole) with sodium styrene sulfonate. FTIR, TGA, XPS, SEM and AFM were used to characterize membrane properties and the results showed that the ion exchange capacity and hydrophilicity of S-PBI increased with increased degrees of grafting and the electric resistance decreased accordingly. When the mass ratio of O-PBI/SSS was 1:4, the electric resistance of S-PBI-4.0 was 4.5 Ω·cm2, while the ion exchange capacity was 2.3 meq/g. The ED experiment with the S-PBI-4.0 membrane exhibited good desalination rate (>96 %), high current efficiency (80.73 %) and low energy consumption (1.13 kW·h/kg), which were very close to the results of a commercial CEM (Neosepta CMX). What's more, because of its good hydrophilicity, the S-PBI-4.0 membrane had better anti-fouling ability than Neosepta CMX, which was manifested as less resistance increase after membrane fouled by bovine serum albumin and smaller resistance after membrane cleaned by deionized water. These results demonstrate that the S-PBI-4.0 membrane is an appropriate candidate CEM and helpful to expand the application of ED in high-salinity organic industrial wastewater treatment. [Display omitted] • A novel CEM of S-PBI was synthesized by thermally induced graft copolymerization. • S-PBI-4.0 has good ionic conductivity and exhibits excellent desalination results. • The S-PBI-4.0 presents superior anti-fouling ability than that of Neosepta CMX. [ABSTRACT FROM AUTHOR]