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Ultrafiltration (UF) is a promising membrane process to remove surfactant-stabilized oil emulsions from produced water (PW). However, UF membranes prepared by conventional methods have suffered from low permeate flux and are susceptible to fouling due to the sparsity of pores on the surface. In this study, we used our recently developed mixed solvent phase separation (MSPS) method to fabricate a highly porous poly (vinylidene fluoride) (PVDF) ultrafiltration membrane for the treatment of produced water. The prepared MSPS PVDF membrane showed an asymmetric high-porous structure with a surface porosity of 23.66% and a narrow pore size distribution of 40 ± 19 nm. The MSPS PVDF membrane showed almost complete oil removal and high oily water permeance above 300 L m−2 h−1·bar−1 even after 72 h of continuous testing, which is an order of magnitude higher than the commercial PVDF membranes. In addition, the MSPS PVDF membrane showed excellent regeneration and recovery capabilities with a flux recovery ratio of 97% without any chemical cleaning, making the process economically and environmentally more viable. Moreover, we achieved optimal membrane performance without any further surface modification processes. [Display omitted] • High-porous PVDF membranes with 23.7% surface porosity was prepared by MSPS method. • Ultrafiltration of produced water showed flux >300 LMH/Bar even after 75 h. • Excellent antifouling properties with >97% flux recovery and 99.99% TOC removal. • Easy flux recovery by a low-pressure DI water backwash without chemical additives. [ABSTRACT FROM AUTHOR]

Nanoporous polyethersulfone (PES) membranes with high surface porosity and uniform pore size distribution were prepared by combining the phase separation in NMP/nonane mixed solvent system with the traditional nonsolvent induced phase inversion process. The effects of PES concentration, nonane concentration, evaporation time, casting solution temperature, and varied mixed solvent systems on the porous PES membrane surface morphology were thoroughly investigated and optimized. The optimized nanoporous PES membrane showed a high surface porosity with a uniform pore size of 20 nm, rendering an exceptional molecular weight cut-off of as low as 100 k Dalton. In addition, the membrane exhibited a significant molecular size exclusion with water permeance of 121 LMH bar−1, bovine serum albumin (BSA) protein rejection of 60.1%, and γ-globulin protein rejection of 99.5% at 0.5 bar, respectively, demonstrating the potential of the as-prepared nanoporous PES membrane for application in protein separation. [Display omitted] • PES membranes with high surface porosity were prepared by the MSPS method. • NMP/nonane system demonstrated a UCST phase behavior. • Asymmetric membrane structure was created by combining MSPS with NIPS. • Promising protein separation was demonstrated on PES membranes. [ABSTRACT FROM AUTHOR]

Mixed Matrix Membranes (MMMs) made from a porous covalent triazine piperazine polymer (CTPP) as filler embedded in poly ether-block-amide (PEBAX® 1657) were studied for the separation of CO 2 /N 2 and CO 2 /CH 4 gas systems. At a loading rate of 0.025 wt%, significant improvement was achieved for both CO 2 permeability (from 53 to 73 barrer) and selectivity (from 51 to 79 for CO 2 /N 2 and from 17 to 25 for CO 2 /CH 4) that were measured at 293 K and 3 bars. Results of FTIR, DSC, WAXS, and SEM revealed a strong interaction between CTPP and PEBAX due to the high density of hydrogen bonding in CTPP, which led to chain rigidification of PEBAX at very low loading rate compared to other literature reported systems. On the other hand, CTPP contains rich nitrogen in the framework, which favourites the adsorption of CO 2 more than N 2 and CH 4. Hence, although the chain rigidification decreased the CO 2 adsorption sites in PEBAX matrix, the intrinsic porosity and high surface area of CTPP compensated the diffusivity and solubility which in turn improved the overall permeability and selectivity at a very low loading rate. CTPP is highly stable in acid, base, and high temperature up to 400 °C. Hence, this novel type material is a very promising filler for preparation of mixed matrix membranes for the separation of CO 2 /N 2 and CO 2 /CH 4 systems. Image 1 • MMMs prepared from a covalent porous polymer filler CTPP in polymer PEBAX. • Strong interactions between CTPP and PEBAX were discovered. • Multiple effects in CTPP/PEBAX MMMs were discovered. • Enhancement in both permeability and selectivity was achieved at very low loading. [ABSTRACT FROM AUTHOR]

[Display omitted] • A solvent-free process was raised to prepare composite solid electrolyte. • A large-scale size of ca. 40 m was demonstrated. • Tensile strength was increased to three times due to the solvent-free feature. • Stable operation without lithium dendrite for over 3700 h was demonstrated. Composite solid-state electrolytes (CSEs) are regarded as a promising alternative for the next‐generation lithium-ion batteries because they integrate the advantages of inorganic electrolytes and organic electrolytes. However, there are two issues faced by current CSEs: 1) a green and feasible approach to prepare CSEs in large scales is desired; and 2) the trace solvents, remaining from the preparation processes, lead to some serious concerns, such as safety hazard issues, electrolyte–electrode interfacial issues, and reduced durability of batteries. Here, a continuous thermal-extrusion process is presented to realize the large-scale fabrication of solvent‐free CSE. A 38.7-meter CSE membrane was prepared as a demonstration in this study. Thanks to the elimination of residual solvents, the electrolyte membrane exhibited a high tensile strength of 3.85 MPa, satisfactory lithium transference number (0.495), and excellent electrochemical stability (5.15 V). Excellent long-term stability was demonstrated by operating the symmetric lithium cell at a stable current density of 0.1 mA cm−2 for over 3700 h. Solvent-free CSE lithium metal batteries showed a discharge capacity of 155.7 – 25.17 mAh g−1 at 0.1 – 2.0C, and the discharge capacity remained 78.1% after testing for 380cycles. [ABSTRACT FROM AUTHOR]