Zhu Tengyang,Zhao Xiaoxu,Yi Ming,Xu Sheng,Wang Yan
To eliminate the interfacial defects between polymeric matrix and inorganic fillers in hybrid membranes, various strategies have been proposed by modifying membrane materials or optimizing membrane formation process. In this work, a ternary cross-linked PVA-APTES-ZIF-90 (PVA, poly(vinyl alcohol); APTES, 3-aminopropyltriethoxysilane; ZIF-90, zeolitic imidazolate framework-90) membrane was developed to eliminate interfacial defects between PVA and ZIF-90 for enhanced ethanol dehydration performance, where APTES served as a covalently linked bridge to cross-link PVA and ZIF-90 simultaneously. The morphologies and physicochemical properties of the resultant membranes were characterized by various characterization techniques. Moreover, we also explored the effects of [ZIF-90]/[APTES] mole ratio and [ZIF-90]/[APTES] loading on the separation performance of the trinity membranes. The results indicated that ZIF-90 particles showed better dispersion and compatibility in PVA-APTES-ZIF-90 trinity membranes than in PVA/ZIF-90 hybrid membrane, attributed to the ternary cross-linking among PVA, APTES, and ZIF-90. Compared with pristine PVA membrane, PVA-APTES-ZIF-90 trinity membranes showed stronger anti-swelling and mechanical properties, as well as more excellent separation performance, which resulted from the incorporation of cross-linker APTES and ZIF-90 particles. The separation factor of the optimal PVA-APTES-ZIF-90 trinity membrane was improved by 215.4%, up to 552, accompanied by a total flux of 82 g/m 2 h. Ternary cross-linking among cross-linker, inorganic filler, and polymeric chain is therefore believed to be a feasible strategy in preparing polymeric-based hybrid membranes with high separation performance. Graphical abstract Summary: A novel ternary cross-linked hybrid membrane with APTES as co-cross-linkers of ZIF-90 and PVA for efficient ethanol dehydration
Xu Wang,Rui Yao,Han Zhu,Zinan Zhang,Lifeng Zhang,Qiang Ma,Hua Jin,Yanshuo Li
Membrane separation has been well acknowledged as a forward-looking technology for hydrocarbon separation. Zeolitic imidazole framework-90 (ZIF-90) with effective pore size of 5.0 Å is a promising membrane material for hydrocarbon separation. Owing to the enormous challenges facing the fabrication process, the research on the ZIF-90 polycrystalline membrane is fairly underexplored. Herein we report a solvent-vapor-triggered crystallization strategy for the production of ZIF-90 membranes. The resultant ZIF-90 membrane had a typical polycrystalline membrane structure where the regular ZIF-90 grains propagated inside the whole porous support. Intriguingly, the membrane displayed two obvious sharp cut-off regions falling between the C 3 H 6 /C 3 H 8 and n- C 4 H 10 / i- C 4 H 10 gas pairs, respectively. The ZIF-90 membrane achieved ultrafast and selective permeation of C 3 H 6 from the C 3 H 6 /C 3 H 8 mixture. The C 3 H 6 flux was about 3.4 kg·m −2 ·h −1 which was comparable to the commercial NaA zeolite membrane for organic solvent dehydration. Further, the distinctive gas transport kinetic nature enabled the ZIF-90 membranes to exclude i -C 4 H 10 and thus harvest unprecedented n -/ i -C 4 H 10 separation ability in high-temperature regions. As the temperature elevated from 25 to 150 °C, the n- C 4 H 10 permeance was enhanced from 3.0 × 10 −9 to 12 × 10 −9 mol·m −2 ·s −1 ·Pa −1 and the n- C 4 H 10 / i- C 4 H 10 separation factors was improved from 63 to 95, respectively. The high permeance and permselectivity at industrially relevant high temperatures and pressures make ZIF-90 membrane attractive for industrial light hydrocarbon separation.
Yahui Cai,Dongyun Chen,Najun Li,Qingfeng Xu,Hua Li,Jinghui He,Jianmei Lu
Special wetting characteristic surfaces typically combine low-surface-energy micro/nanoscale structures, and special wetting coating material applications are wide-ranging, including self-cleaning and drag-reducing surfaces to anti-adhesives. However, the poor durability of these special wetting surfaces greatly limits their practical application, and external conditions such as illumination, friction, and corrosion can damage and destroy the low-surface-energy surface of the superhydrophobic coatings. These low-surface-energy materials must then be redeposited to restore the superhydrophobic coatings, which is cost and time prohibitive. Endowing superhydrophobic coatings with a self-repairing performance could effectively solve these durability problems. Here we report a robust, superhydrophobic metal organic framework layer membrane with a repair ability. This composite membrane was prepared by a simple wet-chemistry coating technique consisting of fluorinated alkyl silane, a fluorocarbon surfactant, and a hydrophobic ZIF-90 membrane. This study represents a durable superhydrophobic membrane for sewage treatment application.
危险品化学品经营许可证（带存储）