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Triboelectric nanogenerators are promising green electrocatalytic alternative energy sources; however, their low current density renders practical applications challenging. Herein, a self‐generating electricity mode based on a droplet friction strategy that significantly mitigates membrane fouling while facilitating the contact of oxidizing substances and sulfamethoxazole within the nanoconfined spaces of 2D conductive catalytic membranes is proposed, which are elaborately designed via the co‐assembly of CoFeMoOOH and MXene laminates. In the confined domain space of the membrane, triboelectric pulses resulted in a 267% (1800  to 4800 min−1) enhancement of the degradation rate constant of sulfamethoxazole, which is significantly higher than the 17% (0.35  to 0.41 min−1) for the suspension system. In situ filtration and kinetic modeling revealed that the pulsed electrical signal generated by the permeate promoted molecular polarization and longitudinal mass transfer within the confined domain space. The alteration in the adsorption‐desorption behavior of solvent/solute molecules between the confined domain layers leads to the migration of water molecules and pollutants in opposite directions, facilitating positive catalytic reactions and fouling inhibition. The proposed self‐generating pulsed electricity‐assisted nanoconfined catalysis offers a powerful tool for efficiently harnessing environmental micro‐energy for the green upgrading of water treatment processes. [ABSTRACT FROM AUTHOR]

The effect of membrane properties, feed water quality, and permeate flux on ultrafiltration (UF) membrane fouling was systematically investigated. Fouling tests were carried out with three types of commercially available UF membrane and a variety of influents. The membrane fouling was assessed by the normalized fouling rate (F500). The results showed that the PVDF membrane with smaller contact angle was more resistant to membrane fouling than the PVC membrane. As for feed water parameters, significant correlations were observed between turbidity, total organic carbon, UV254, fluorescence intensity, and membrane fouling rates using Pearson Correlation Analysis. This was especially true for hydraulically irreversible fouling rate (Firr). Moreover, significant correlations between permeate fluxes and membrane fouling rates were observed. With these correlations, the critical flux and critical flux for irreversibility were calculated. It was found that the critical flux is strongly depended on feed water composition rather than membrane properties. Particulate matter, with a size of 0.45–1.2 μm in diameter, was proved to increase the critical flux and critical flux for irreversibility. [ABSTRACT FROM PUBLISHER]

To investigate the effect of hydrodynamic conditions on hydraulically irreversible fouling of UF membrane in MBR for treating micro-polluted water, the method of determination of hydraulically irreversible fouling of UF membrane was introduced, and the effects of aeration, backwashing, flux and temperature on irreversible fouling were discussed. The results showed that the pollutant removal of MBR should be taken into account when selecting the time and flow of aeration. The duration of 2 min was necessary during intermittent aeration, with the optimal aeration intensity of 30 - 36 m³/ (m² ⋅ h). Prolonged backwashing duration was found to control the hydraulically irreversible fouling. The production of UF membrane in MBR should also be considered when determining the proper backwashing duration. The permeate fluxes influenced the hydraulically irreversible fouling rate significantly, and the values of PVDF and PVC membranes should be no more than 31.5 and 14.0 L/(m² ⋅ h) lo maintain lhe long-term stable operation. Meanwhile, the impact of temperature on irreversible fouling should be considered. [ABSTRACT FROM AUTHOR]

Membrane distillation technology, utilized for treating hypersaline wastewater from seawater desalination, often encounters challenges related to inorganic scaling, adversely affecting membrane performance. Herein, we introduce a innovative approach employing a sacrificial layer on the surface of Thin Film Composite (TFC) membranes to concurrently enhance inorganic scaling resistance and facilitate membrane reusability. The sacrificial layer (Fe3+-TA) consisted of tannic acid (TA) complexed with iron ions (Fe3+) and could be removed and regenerated in situ. The results demonstrated that the Fe3+-TA layer significantly improved the membrane's surface smoothness and densification, maintaining superior anti-scaling performance. The modified membrane exhibited remarkable durability, sustaining six reuse cycles with a flux recovery exceeding 97 % in gypsum scaling tests. Furthermore, the formation of new complexes during gypsum scaling tests confirmed the membrane's augmented scaling retardation capabilities. Thus, integrating of a sacrificial layer into TFC membranes presents a promising strategy for advancing membrane distillation processes in hypersaline wastewater treatment. [Display omitted] • A sacrificial layer was first introduced to membrane distillation for scaling resistance. • Fe3+-TA coatings can be removed and re-coated in situ. • The coated membrane demonstrated excellent scaling resistance. • Sacrificial protective layer showed sustainable performance during long-term test. [ABSTRACT FROM AUTHOR]

Mineral scaling and scaling-induced wetting are major challenges for the widespread application of membrane distillation (MD) in saline wastewater treatment. For the first time, an in-line modified activated alumina (AA) granular filtration coupled with MD process was proposed to achieve effective control of gypsum scaling. Firstly, the AA modified by NaOH impregnation with tuned pore structure and surface characteristics were supplied as the filter media. The optimized MD performance was obtained using in-line filtration with modified AA (MAA) with 20 g/L NaOH and the ratio of AA and NaOH solution of 1:3 for the duration of 24 h. Compared with severe scaling without granular filter, the optimized performance with a final normalized flux higher than 0.7 and a permeate conductivity less than 5 μS/cm at 70 % water recovery was observed. The MAA with rich pore, scale-like structures and high Na loading showed a superior ability in capturing gypsum scaling due to the enhanced heterogeneous scaling and the retention of scaling. In-line granular filtration-MD was also effective in mitigating gypsum scaling and scaling-induced wetting in saline solutions (e.g., 7–12 g/L NaCl). Our findings provide guidance for surface design of granular filter media and scaling control in membrane desalination technology. [Display omitted] • MD integrated with in-line granular filtration successfully mitigated gypsum scaling. • In-line filtration-MD increased water recovery to 70 % from 37.5 % under off-line mode. • The Al 2 O 3 filter media after NaOH impregnation increased final MD flux by 3.6 times. • In-line granular filtration reduced gypsum scaling on MD surface by 34.5–84.5 %. • Structure–property relationship of scaling and media characteristics was revealed. [ABSTRACT FROM AUTHOR]

The scaling-induced wetting phenomenon seriously affects the application of membrane distillation (MD) technology in hypersaline wastewater treatment. Unlike the large amount of researches on membrane scaling and membrane wetting, scaling-induced wetting is not sufficiently studied. In this work, the current research evolvement of scaling-induced wetting in MD was systematically summarized. Firstly, the theories involving scaling-induced wetting were discussed, including evaluation of scaling potential of specific solutions, classical and non-classical crystal nucleation and growth theories, observation and evolution of scaling-induced processes. Secondly, the primary pretreatment methods for alleviating scaling-induced wetting were discussed in detail, focusing on adding agents composed of coagulation, precipitation, oxidation, adsorption and scale inhibitors, filtration including granular filtration, membrane filtration and mesh filtration and application of external fields including sound, light, heat, electromagnetism, magnetism and aeration. Then, the roles of operation conditions and cleaning conditions in alleviating scaling-induced wetting were evaluated. The main operation parameters included temperature, flow rate, pressure, ultrasound, vibration and aeration, while different types of cleaning reagents, cleaning frequency and a series of assisted cleaning measures were summarized. Finally, the challenges and future needs in the application of nucleation theory to scaling-induced wetting, the speculation, monitoring and mitigation of scaling-induced wetting were proposed., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Treatment of recalcitrant landfill leachate (LFL) induces huge energy consumption and carbon emissions due to its complex composition. Although membrane distillation (MD) exhibits good potential in LFL treatment with waste heat utilization, membrane fouling and ammonia rejection are still the major problems encountered that hinder its application. Herein, membrane electrochemical reactor (MER) was coupled with MD for simultaneous membrane fouling control and resource recovery. LFL pretreatment with membrane-less electrochemical reactor (EO) and without pretreatment were also purified by MD for comparison. Results showed that the MER-MD system rejected almost all COD Cr , total phosphorus, metal salts, and ammonia nitrogen (increased by 33.5%-43.5% without chemical addition), and recovered 31% of ammonia nitrogen and 48% of humic acid in the raw LFL. Owing to the effective removal of hardness (61%) and organics (77%) using MER, the MER-MD system showed higher resistance to the membrane wetting and fouling, with about 61% and 14% higher final vapor flux than those of the MD and EO-MD systems, respectively, and the pure water flux could be fully recovered by alkaline solution cleaning. Moreover, SEM-EDS, ATR-FTIR and XRD characterization further demonstrated the superiority of the MD membrane fouling reversibility of the MER-MD system. Energy consumption and carbon emissions analysis showed that the MER-MD system reduced the total energy consumption/carbon emissions by ∼20% and ∼8% compared to the MD and EO-MD systems, respectively, and the ammonia nitrogen recovered by MER could offset 8.25 kg carbon dioxide equivalent. Therefore, the introduction of MER pretreatment in MD process would be an option to decrease energy consumption and reduce carbon emissions for MD treatment of LFL., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:, (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Desulfurization wastewater in coal-fired power plants (CFPPs) is a great environmental challenge. This study aimed at the current status and future research trends of desulfurization wastewater by bibliometric analysis. The desulfurization wastewater featured with high sulfate (8000 mg/L), chlorite (8505 mg/L), magnesium (2882 mg/L) and calcium (969 mg/L) but low sodium (801.82 mg/L), and the concentrations of the main contaminants were critically summarized. There was an increasing trend in the annual publications of desulfurization wastewater in the period from 1991 to 2021, with an average growth rate of 15%. Water Science and Technology, Desalination and Water Treatment, Energy & Fuels, Chemosphere, and Journal of Hazardous Materials are the top 5 journals in this field. China was the most productive country (58.3% of global output) and the core country in the international cooperation network. Wordcloud analysis and keyword topic trend demonstrated that removal/treatment of pollutants dominated the global research in the field of desulfurization wastewater. The primary technologies for desulfurization wastewater treatment were systematically evaluated. The physicochemical treatment technologies occupied half of the total treatment methods, while membrane-based integrated processes showed potential applications for beneficial reuse. The challenges and outlook on desulfurization wastewater treatment for achieving zero liquid discharge are summarized., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Paralytic ileus is common in patients with septic shock, causing high morbidity and mortality. Enteric neurons and enteric glial cells (EGCs) regulate intestinal motility. However, little is known about their interaction in endotoxemia. This study aimed to investigate whether reactive EGCs had harmful effects on enteric neurons and participated in intestinal motility disorder in mice during endotoxemia. Endotoxemia was induced by the intraperitoneal injection of lipopolysaccharide (LPS) in mice. Fluorocitrate (FC) was administered before LPS injection to inhibit the reactive EGCs. The effects of reactive EGCs on intestinal motility were analyzed by motility assays in vivo and colonic migrating motor complexes ex vivo. The number of enteric neurons was evaluated by immunofluorescent staining of HuCD, nNOS, and ChAT in vivo. In addition, we stimulated EGCs with IL-1β and TNF-α in vitro and cultured the primary enteric neurons in the conditioned medium, detecting the apoptosis and morphology of neurons through staining TUNEL, cleaved caspase-3 protein, and anti-β-III tubulin. Intestinal motility and peristaltic reflex were improved by inhibiting reactive EGCs in vivo. The density of the neuronal population in the colonic myenteric plexus increased significantly, while the reactive EGCs were inhibited, especially the nitrergic neurons. In vitro, the enteric neurons cultured in the conditioned medium of reactive EGCs had a considerably higher apoptotic rate, less dendritic complexity, and fewer primary neurites. Reactive enteric glial cells probably participated in paralytic ileus by damaging enteric neurons during endotoxemia. They might provide a novel therapeutic strategy for intestinal motility disorders during endotoxemia or sepsis., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)