A novel class of mixed-matrix membranes was synthesized through strategic integration of Polyether-block-amide (PEBAX) with Deca-dodecasil 3R (DD3R) zeolitic fillers, targeting efficiency-driven ethanol recovery in pervaporation separation systems. The DD3R molecular sieve was synthesized using adamantylamine (ADA) as a structure-directing agent and Sigma-1 seed crystals in a pure silicon precursor system. To improve compatibility with the polymer matrix, the DD3R particles were surface-modified with a silane coupling agent. Comprehensive characterization through Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectra (XPS), Water Contact Angle (WCA), X-ray diffraction (XRD), swelling degree tests, and mechanical properties confirmed the successful bonding of the silane coupling agent to both DD3R and PEBAX. The optimized membrane containing 0.75 wt.% DD3R achieved a flux of 1152.06 g/m 2 h and a separation factor of 4.52 at 60 o C with a 5 wt.% ethanol feed concentration, representing a 115 % enhancement in flux and a 68 % increase in separation factor compared to the pristine PEBAX membrane. Additionally, the PEBAX/DD3R membrane displayed excellent long-term stability. This work provided a foundation for developing membranes with DD3R incorporated therein for a wide range of liquid or gas mixture separation processes.
Xi Chen,Zhenggang Wang,Zhuo Yang,Guozhen Liu,Guining Chen,Gongping Liu,Xiuxia Meng,Naitao Yang,Wanqin Jin
Towards natural gas purification , polymeric membranes generally face challenges of trade-off between permeability and selectivity , as well as CO 2 -induced plasticization effect. Previous works demonstrated that incorporating high-performing nanofillers and crosslinking the polymers are effective methods to overcome these two issues, respectively. In this work, we aimed to simultaneously improve permeability, selectivity and plasticization resistance of polymeric membranes by incorporating surface-engineered nanoporous fillers for CO 2 /CH 4 separation. DD3R zeolite nanoparticles with high purity were synthesized and then surface-functionalized by 3-aminopropyl trimethoxysilane (APTMS) to serve as the filler. Mixed-gas permeation measurements showed that DD3R zeolites offered CO 2 -selective channels in 6FDA-DAM polyimide based on molecular sieving effect of zeolitic aperture. 30 wt% DD3R-APTMS zeolite imparted the membrane with CO 2 permeability of 1661 Barrer (increased by 71.7%) and CO 2 /CH 4 selectivity of 28.0 (increased by 44.5%), which was beyond the upper-bound of polymeric membranes. Meanwhile, the hydrogen bond interaction between amino groups on APTMS and carboxyl groups on 6FDA-DAM rendered the resulting DD3R-APTMS MMMs highly enhanced plasticization resistance over 40 bar when equimolar CO 2 /CH 4 mixture as the feed. This work demonstrates a facile approach to simultaneously enhance separation performance and mitigate the plasticization effect.
危险品化学品经营许可证（带存储）