Interface assembled from Preparative thin composite membrane having a separation layer of gas through the transmission channel
CO2 is the key to efficient separation of CO2 emissions and energy gas purification, membrane technology with its low energy consumption, operating flexibility, and environmentally friendly advantages become one of the most promising industrial CO2 separation technology. Mixed matrix membrane bound nanofiller polymers with their respective advantages, both alone and is expected to avoid the deposition problem may occur, causing widespread attention in the field of gas separation membrane. Currently, most of the continuous phase polymer is wrapped mixed matrix membranes reported in the porous material, resulting in transfer of the advantages of the porous material can not be fully realized. Thus, the advantages of how to make the transfer of the porous material should be a key factor to enhance the performance of the mixed matrix membrane gas separation. In view of this, Tianjin University Professor Wang Task Force and the Professor Michael D. Guiver Task Force In \” Advanced Materials \”entitled the\” unobstructed Ultrathin Gas Transport Channels in Composite Membranes by Interfacial Self-Assembly \”research paper . This study provides A simple method of gas separation composite membrane and thin passage through the high-speed transmission is constructed of MOF layer is separated, which give full play to the advantages of porous material transfer, significantly improve the film properties. In this study, polyvinylamine (PVAm) and γ- glycidoxypropyl trimethoxysilane (of KH560) interfacial layer consisting of nanoparticles of MIL-101 (Cr) hydrophilic modification, KH560 form a covalent bond tightly connected to MIL-101 (Cr) and PVAm, the modified nanoparticles named MKP, the modification process as shown in FIG. (B) it is seen from FIG. 2, the contact angle of the modified MKP significantly reduced, indicating an increase in hydrophilicity of MKP.
the specific process film (2) further comprises a hydrophilic modified polysulfone support layer (MpSF) (FIG. 2 ( a)) and MKPInterfacial self-assembly (FIG. 2 (c)) between the nanoparticles with the polymer matrix PVAm. First, MKP nanoparticle dispersion liquid film is formed PVAm aqueous solution, the film was drawn down over the support layer mPSf, MKP nanoparticle density is greater than its rapid subsidence PVAm solution, preferentially contacting mPSf support layer. FIG 2 contact angle measurement results show that the hydrophilic support layer than mPSf MKP nanoparticles show hydrophilically modified difficult to completely change the nature of the hydrophobic nanoparticles, modified main purpose is to improve the interface between the nanoparticles with the polymer matrix compatibility, while increasing the amount of added nano-particles to prevent agglomeration of nanoparticles appear in a hydrophilic environment. Then, along with the volatile water-continuous, and continuous phase tends PVAm mPSf more hydrophilic support layer in contact, resulting in a continuous polymer phase is attached by suction to the body surface of the particles in a small amount of PVAm departing from the surface of the particles and nano-MKP MKP nano . In this study, we PVAm polymer film by controlling the thickness of the separation layer (~ 200 nm), MKP to be smaller than size of the nanoparticles (220 nm), the MKP PVAm filled between the nanoparticles and the surface does not cover the MKP. Thus, a mixed matrix arrangement is a single layer film made of MKP nanoparticles may be passed through the passage as a gas separation layer.
at 0.5MPa, MKP nanoparticles are added in an amount 44.44 wt%, the produced film CO2 permeation rate of 823 GPU, CO2 / N2 separation factor of 242, as compared with the particle film was not added, are promoted and 4.93 times 2.35 times, the flue gas in a simulated real environment a film performance good long-term stability. The method of the present design and Preparation of thin composite membrane having a separation layer through the transfer passage is simple, practical, it can be prepared by mixing with a variety of transmission channels through the separation layer by changing the porous material and the polymer matrix matrix membrane, for efficient separation of gases. Related papers published in Advanced Materials (DOI: 10.1002 / adma.201907701). This study wasTo the key national research and development program (project number: 2017YFB0603400), National Natural Science Foundation (project number: 21436009) funding. The full text link: https: //onlinelibrary.wiley.com/doi/epdf/10.1002/adma.201907701