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Highly permeable organic solvent nanofiltration (OSN) membranes are desired to be used in an efficient and energy-saving chemical separation process. Herein, we fabricated a high-flux OSN membrane by synthesizing 7,7′-dihydroxy-2,2′-binaphthol (7,7′-OH-BINOL) as an aqueous phase monomer to react with trimesoyl chloride (TMC) via interfacial polymerization. The unique structures of 7,7′-OH-BINOL having a rotatable highly kinked unit and a rigid binaphthol ring endow the fabricated polyarylate membrane with very high microporosity and super-high Young's modulus. Both simulated and experimental results demonstrate that the BINOL-based polyarylate (PAR-BINOL) membrane has two types of micropores including cross-linked pores and stacked pores. Our results find that the PAR-BINOL membrane exhibits very high solvent permeance over a wide range of solvents with diverse polarity, and also possesses a long-term stable separation performance in solvents. Impressively, the membrane solvent permeance can reach up to 28.7 L m−2 h−1 bar−1, 9.2 L m−2 h−1 bar−1 and 6.7 L m−2 h−1 bar−1 for acetone, methanol, and dimethylformamide (DMF), respectively. The rejection of tetracycline (TC, Mw = 444 g mol−1) is 98.2%. Our work provides some insights into the molecular engineering of monomers with unique contorted and rigid structures for the fabrication of highly permeable OSN membranes.

Zwitterions have been attracting great attention for researchers to tailor the separation membranes featuring enhanced water permeability and excellent antifouling property. Here we functionalized polyamide membrane surface with small-molecule zwitterions through sequential interfacial polymerization (SIP) technique to improve the performance of RO membranes. Zwitterionic molecules 3-(4-(2-((4-aminophenyl)amino)ethyl)morpholino-4-ium)propane-1-sulfonate (PPD-MEPS) and amino acid arginine were covalently bonded onto the PA surface via the amine groups of two zwitterions. Consequently, the surface hydrophilicity of both modified membranes were significantly improved with WCA decreased from ~60° to ~28°, and their surface negative charge also decreased to some extent at high pH values. The water permeability increased from 2.45 LMH/bar to 3.81–3.85 LMH/bar, increasing by about 57%, while maintained a NaCl rejection as high as 98.5%. In addition, the zwitterions-modified RO membranes exhibited much improved antibacterial attachment (E.coil) and fouling resistance to model foulants bovine serum albumin (BSA), lysozyme (LYZ) and humic acid (HA). Therefore, the facile zwitterions modified membranes possessing high water permeability and excellent antifouling performance, especially using amino acid Arg may find their potential promising application in water treatment.

A fluidized bed system was demonstrated and the fluidization performances of silicon carbide in the fluidized bed system were experimentally studied as to facilitate the further application of microwave-assisted fluidized bed. The results show that the smaller silicon carbide particles (0.25–1 mm) have better fluidization performances than larger ones (1–1.5, 1.5–2, 2–2.5 and 2.5–3 mm) due to the fact that the smaller particles are nearly spherical whereas the larger particles are irregular in shape (long and branched), and larger particles tend to form channels in fluidization. Fluidization velocity is too high, large bubbles will be generated to affect the uniformity of fluidized particles. The loading of fluidized particles should match that of the fluidized bed, and too low loading amount wastes the space of the fluidized bed, while too high loading amount will also produce large bubbles. For the fluidized bed system developed in this study, the suggested fluidization parameters were: (a) silicon carbide particle size of 0.25–1 mm, (b) fluidization velocity of 0.47–-0.71 m/s, and (c) silicon carbide particle loading of 40–50 g.

Fluidization is an effective method to better help the transfer and conversion of fuel particles. In this study, intensification of the fluidization performances of polypropylene was experimentally investigated by using microwave absorbent. The fluidization performances of polypropylene (PP) were initially presented and the effects of microwave absorbent (SiC) particle size, mass ratio of SiC to PP, and fluidization velocity on the co-fluidization performances were studied and presented. The results showed that the PP load significantly increased the initial bed height whereas slightly increased the critical fluidization velocity and bed expansion ratio. Adding microwave absorbent (SiC) can effectively improve the fluidization performance of PP particles. The smaller SiC particles (0.25−1 mm) had better fluidization performances than the larger ones (1–1.5 mm and 1.5−2 mm). The mass ratio of silicon carbide to polypropylene decreased the critical fluidization velocity. Fluidization velocity significantly affected the co-fluidization performance. For the co-fluidization of polypropylene and silicon carbide in the designed fluidized bed, the recommended fluidization parameters were: (a) the particle size of silicon carbide of 0.25–1 mm, (b) the mass ratio of silicon carbide to polypropylene of 3:2, and (c) the fluidization velocity of 0.66 m/s.

α-Fe2O3@C core–shell nanorings are prepared by a facile large-scale two-step route incorporating a hydrothermal method and a carbon coated progress. Its structure and morphology are characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscope, and thermogravimetry. It is found that the as-prepared composite is composed of α-Fe2O3@C nanorings of about 148 nm in outer diameter, 50 nm in thickness, and 115 nm in length. These α-Fe2O3@C nanorings are enwrapped with ∼3 nm thick carbon shell. And the electrodes exhibit longer cycle life (815 mAhg−1 after cycling 160 times) at high current rate (1000 mAg−1) compared with that of bare α-Fe2O3 nanorings (810 mAhg−1 after cycling 30 times). The improved performance of the composite is attributed to the bondage from carbon shell, which can enhance the electronic conductivity and structural stability of α-Fe2O3 nanorings.