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Membranes are widely used for liquid separations such as removing solute components from solvents or liquid/liquid separations. Due to negligible vapor pressure, adjustable physical properties, and thermal stability, the application of ionic liquids (ILs) has been extended to fabricating a myriad of membranes for liquid separations. A comprehensive overview of the recent developments in ILs in fabricating membranes for liquid separations is highlighted in this review article. Four major functions of ILs are discussed in detail, including their usage as (i) raw membrane materials, (ii) physical additives, (iii) chemical modifiers, and (iv) solvents. Meanwhile, the applications of IL assisted membranes are discussed, highlighting the issues, challenges, and future perspectives of these IL assisted membranes in liquid separations.

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Herein, thin-film composite membranes consisting of poly(m-phenyleneisophthalamide) substrate and polyamide active layer were constructed by transition metal ionassisted interfacial polymerization method. As compared to the traditional polyamide membranes, a much thinner polyamide layer (33 vs. 200 nm) can be synthesized with higher permeance (3.2 vs. 0.62 L m À2 h À1 bar À1 ) in the organic solvent nanofiltration.

In this work, we have developed a novel and facile method to prepare gallic acid-grafted chitosan/polysulfone (PS) composite membranes for dye removal from aqueous solutions. First, the gallic acid was grafted onto the eco-friendly chitosan through a free-radical grafting copolymerization reaction. Second, the gallic acid-grafted chitosan conjugates were codeposited onto the top surface of PS substrates by electrostatic interactions in order to transform the ultrafiltration membrane to the thin and defect-free nanofiltration membrane. The morphology and chemical composition of the as-prepared composite membranes were fully characterized by various spectroscopy and microscopy techniques. Moreover, after the optimization of preparation parameters, the obtained membrane displayed a high rejection of 97.2% for Congo red with a high permeance of 14.0 L h −1 m −2 bar −1 . Furthermore, the composite membranes also exhibited good rejections for other dyes with different molecular weights such as Evan blue (97.3%), Acid red 94 (97.6%), and Alcian blue 8GX (98%) on the basis of size exclusion, accompanied with good permeance of 12.9, 11.9, and 10.9 L h −1 m −2 bar −1 , respectively, which shows potential for scale-up industrial applications.

The α‐L‐Rhamnosidase (Rha) is a useful glycoside hydrolase for selectively hydrolyzing the terminal L‐rhamnose residues in flavonoids, being vital to food and pharmaceutical industries. However, Rha suffers from low recyclability and poor stability in harsh environments. Herein, we explored five typical metal‐organic frameworks (MOFs) as porous carriers to immobilize Rha, and the activities of the resultant Rha@MOF composites were compared with the free enzyme. The locations of the enzyme in MOFs were proved by a series of characterization techniques. It was found that Rha@Ce‐BTC (with enzyme immobilization efficiency of 23 % and enzyme loading content of 8.8 %) showed the highest enzymatic activity. The immobilized Rha@Ce‐BTC showed 80 % residual activity after five consecutive cycles, suggesting a limited leaching effect. Also, Rha@Ce‐BTC manifested markedly enhanced enzyme‐substrate affinity and catalytic efficiency compared to free Rha, as supported by Michaelis‐Menten kinetic studies. Accordingly, the Ce‐BTC would be an appealing carrier for enzyme immobilization, and the as‐designed enzyme/Ce‐BTC composites are promising candidates for industrial use with remarkably high activity, recyclability, and storage stability.