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[Display omitted] • Rapid co-deposition of dopamine and APTS was used to construct superhydrophilic membranes. • Superhydrophilic membrane had an effective oil repellency with underwater oil contact angle of ∼163.5°. • Superhydrophilic membrane has a fast gravity-driven filtration for oil-in-water emulsions with a separation efficiency of >99.9 % • Incorporation of Cu NPs and polydopamine enables the membranes with complete antibacterial activity. Substantial discharge of industrial oily wastewater calls for an efficient and sustainable treatment for resource recovery. Superwetting membranes offer a feasible approach to fractionate oil species and water from oily wastewater for addressing this technical challenge. In this study, we proposed a useful strategy for constructing a superhydrophilic membrane with superior antibacterial properties through rapid co-deposition of dopamine and 3-aminopropyltriethoxysilane (APTS) initiated by ammonium persulfate on the Cu nanoparticles-loaded porous PVDF substrate. The resultant superhydrophilic membrane yielded an underwater oil contact angle of 163.5°, enabling a fast and robust gravity-driven filtration for various oil-in-water emulsions with a separation efficiency of >99.9 %. Additionally, incorporating of Cu nanoparticles and polydopamine endowed the superhydrophilic membrane with superior antibacterial activity (100 % inhibition efficiency against Escherichia coli), and thereby remarkably enhancing the anti-biofouling performance. This study provides a viable approach to design high-performance membranes for separation of oil-in-water emulsions, with promising applications in the industrial and environmental sectors. [ABSTRACT FROM AUTHOR]

[Display omitted] • ● Simultaneous extraction and stripping of light rare earth elements were conducted. • ● Hollow fiber supported liquid membrane system with P507 as extractant effectively fractionate La3+ and Nd3+. • ● No saponification was required by hollow fiber supported liquid membrane system for LREEs fractionation. • ● Hollow fiber supported liquid membrane system had the superior selectivity for Nd3+. Rare earth elements (REEs) are commonly categorized into light (LREEs), medium (MREEs), and heavy (HREEs) groups. Separation between LREEs and MREEs or MREEs is relatively straightforward. However, isolating LREEs themselves is particularly challenging because of their similar ionic radii and identical charges. Traditional separation processes are hindered by drawbacks including low recovery rates for dilute REEs, poor selectivity, complex protocols, and environmental pollution. Consequently, developing a cleaner and more efficient method for LREEs separation is imperative. In this study, we employed a single-module hollow fiber supported liquid membrane (HFSLM) system with 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (P507) as an extractant to concurrently extract and strip La3+ and Nd3+ from the mixed LREEs containing solutions. We also investigated the impact of flow rate, stripping solution acidity, feed solution pH, P507 concentration, Nd3+ concentration of feed solution, and the volume ratio between the feed and stripping solutions influence the extraction and stripping of LREEs, as well as the molar fractions of La3+ and Nd3+ in the solutions. Under optimal condition, the molar fraction of La3+ was 99.0% in the feed solution, whereas the molar fraction of Nd3+ reached 91.6% in the stripping solution. Furthermore, the experimental results demonstrated a consistent preference of P507-HFSLM system for extracting Nd3+ over La3+, and the underlying mechanism was thoroughly investigated. In summary, this study offers comprehensive insights and technical approaches for selective separation and purification of LREEs. [ABSTRACT FROM AUTHOR]

High-salinity textile wastewater is a pressing environmental concern, urgently requiring the appropriate treatment. Sustainable management of high-salinity textile wastewater via fractionation of the existing dyes and inorganic salts (NaCl) using selective separation membranes is a key approach to address this detrimental concern. Herein, tight composite ultrafiltration membranes with impressive antibacterial function were constructed using one-step co-deposition of dopamine and tobramycin on the porous substrate to fractionate the dyes and NaCl. Triggered by ammonia persulfate, the polydopamine/tobramycin coating layer imparts the fabricated composite ultrafiltration membranes with tight surface structure and narrow pore size distribution, enabling effective dyes/salts fractionation. Specifically, the tight composite ultrafiltration membrane with a molecular weight cutoff of 3692 Da experienced a > 98.0 % rejection against various reactive dyes (molecular weight: <1000 Da) with nearly complete salt transmission (<0.8 % NaCl rejection), demonstrating an effective fractionation of dyes and salts. Additionally, the incorporated tobramycin as a broad-spectrum antibiotic endowed the tight composite ultrafiltration membrane with a sufficient inhibition efficiency (i.e., 100 %) against E. coli bacteria in a short-time contact (i.e., 3 min). Thereby, the tight composite ultrafiltration membrane constructed by fast co-deposition of dopamine and tobramycin established an unparalleled platform technology for sustainable resource recovery (dyes or salts) from high-salinity textile wastewater. [Display omitted] • Tight ultrafiltration (UF) membrane with 3692 Da MWCO was designed by rapid co-deposition of dopamine and tobramycin. • Tight UF membrane had an impressive rejection of >98.0 % for various reactive dyes with >99.2 % NaCl transmission. • Tight UF membrane showed a robust stability in fractionation of dyes and salts. • Tight UF membrane yielded a 100 % inhibition efficiency against E. coli for mitigating the biofouling. [ABSTRACT FROM AUTHOR]

This study reports the fabrication of mixed matrix membranes (MMMs) using immersion precipitation phase inversion for promising application in desalination of dye solutions. Aromatic poly(m-phenylene isophthalamide) is used as the polymer material, and the metal-organic framework MIL-53(Al) is added to develop integrally skinned asymmetric membranes. Successful dispersion of MIL-53(Al) particles into the membrane-separating layer is confirmed by scanning electron microscopy. The optimum performance of the membranes is obtained at 0.5 wt % MIL-53(Al) concentration. In particular, the M-0.5 membrane is planned for use in separating dye/salt aqueous mixtures. It is observed that the M-0.5 membrane has a rejection for NaCl and Na2SO4 below 11% and 37%, respectively, in mixed salt/dye solutions. Additionally, the M-0.5 membrane is found to have a rejection rate of 83.9%, 98.3%, and 99.8% for nitroso-R salt, xylenol orange, and ponceau S, respectively, in mixed Na2SO4/dye solutions. The rejection rate for Na2SO4 is lower than that of some commercial nanofiltration membranes (NF90, NF270, and DK). The membrane is promising for dye desalination in industrial-scale applications. [ABSTRACT FROM AUTHOR]

Effective extraction of useful resources from high-salinity textile wastewater is a critical pathway for sustainable wastewater management. In this study, an integrated loose nanofiltration-electrodialysis process was explored for simultaneous recovery of dyes, NaCl and pure water from high-salinity textile wastewater, thus closing the material loop and minimizing waste emission. Specifically, a loose nanofiltration membrane (molecular weight cutoff of ~800 Da) was proposed to fractionate the dye and NaCl in the high-salinity textile wastewater. Through a nanofiltration-diafiltration unit, including a pre-concentration stage and a constant-volume diafiltration stage, the dye could be recovered from the high-salinity textile wastewater, being enriched at a factor of ~9.0, i.e., from 2.01 to 17.9 g·L−1 with 98.4% purity. Assisted with the subsequent implementation of electrodialysis, the NaCl concentrate and pure water were effectively reclaimed from the salt-containing permeate coming from the loose nanofiltration-diafiltration. Simultaneously, the produced pure water was further recycled to the nanofiltration-diafiltration unit. This study shows the potential of the integration of loose nanofiltation-diafiltration with electrodialysis for sufficient resource extraction from high-salinity textile wastewater. [Display omitted] • Integration of loose nanofiltration (NF) with electrodialysis is proposed for textile wastewater treatment. • Loose NF-diafiltration enriches the dye from 2.01 to 17.9 g·L−1 with a purity of 98.4%. • 99.94% of salt is removed by loose NF-diafiltration with 7 diavolumes. • Subsequent electrodialysis effectively recovers water and salt from NF-diafiltration permeate. • No significant fouling of ion exchange membranes is observed in electrodialysis performance. [ABSTRACT FROM AUTHOR]