In this paper, poly（amide-6-b-ethylene oxide） （Pebax1657）/SAPO-34 mixed matrix membranes （MMMs） were prepared by solvent-evaporation method with acetic acid as a novel solvent. CO2, N2, CH4 and H2 permeation pro...In this paper, poly（amide-6-b-ethylene oxide） （Pebax1657）/SAPO-34 mixed matrix membranes （MMMs） were prepared by solvent-evaporation method with acetic acid as a novel solvent. CO2, N2, CH4 and H2 permeation properties were investigated, and the physical properties of Pebax/SAPO-34 MMMs were characterized by XRD and SEM. At low SAPO-34 content, it was homogeneously distributed in the Pebax ma- trix, and then precipitated and agglomerated at high SAPO-34 content. The crystallinity of Pebax phase in Pebax/SAPO-34 MMMs decreased initially and then rebounded as a result of phase separation. With the increase of transmembrane pressure difference, CO2 permeability was en- hanced due to the effect of pressure-induced plasticization. Owing to the happening of stratification, the CO2 permeability of Pebax/SAPO-34 MMMs （50 wt% SAPO-34） increased to 338 Barrer from 111 Barrer of pristine Pebax, while the selectivities of CO2/CH4 and CO2/N2 were almost unchanged. Compared with the pristine Pebax, the gas separation performances of Pebax/SAPO-34 MMMs were remarkably enhanced.展开更多
Zeolitic imidazolate framework-8(ZIF-8)is a typical filler used to fabricate mixed matrix membranes(MMMs)on account of its attractive advantage of high selective permeability for gas separation.However,the performance...Zeolitic imidazolate framework-8(ZIF-8)is a typical filler used to fabricate mixed matrix membranes(MMMs)on account of its attractive advantage of high selective permeability for gas separation.However,the performance is usually affected by filler aggregation due to strong interactions among fillers and weak interactions between the polymer and fillers,However,the performance is usually affected by filler aggregation due to strong interactions among fillers and weak interactions between the polymer and fillers,which will lead to a decrease of selectivity and the performance of gas separation will be strongly influenced.Herein,we modified ZIF-8 with 3-amino-1,2,4-triazole to obtain ZIF-8-NH_(2),Kapton polyamide acid was selected as the polymer matrix.Results showed that the ZIF-8-NH_(2)/Kapton MMMs has a good compatibility interface between ZIF-8 and Kapton because of the covalent bridging,even the filler loading up to 45%(mass).The 45%(mass)of ZIF-8-NH_(2)/Kapton membrane showed 297 barrer(1 barrer=10^(-10)10 cm^(3)·cm·cm^(-2)·s^(-1)·cmHg^(-1),1 cmHg=1333.22 Pa,standard temperature and pressure)of the permeability of H_(2)and 43.9 and 62.2 of selectivities for H_(2)/N_(2)and for H_(2)/CH_(4),respectively,which are beyond the upper limit of Robeson 2008.展开更多
Nowadays,mixed matrix membranes(MMMs)have considered by many researchers to overcome the problems of polymeric membranes.In addition,molecular dynamics(MD)and Monte Carlo(MC)simulation Methods are suitable tools for s...Nowadays,mixed matrix membranes(MMMs)have considered by many researchers to overcome the problems of polymeric membranes.In addition,molecular dynamics(MD)and Monte Carlo(MC)simulation Methods are suitable tools for studying transport properties and morphology in MMMs.For this purpose,in this study using material studio 2017(MS)software,the transport properties of CO2,CH4 and N2 in Pebax,Psf neat Pebax/Psf composite and Pebax/Psf composite filled with ZIF-90 particles have been investigated.By adding Psf to Pebax matrix,the selectivity of CO2/CH4 and CO2/N2 gases has significantly increased.In addition,adding ZIF-90 particles to the Pebax/Psf composite increased the permeability of CO2,CH4 and N2 compared to neat and composite membranes.The morphological properties of the membranes,such as the fractional free volume(FFV),radial distribution function(RDF),glass transition temperature(TG),X-ray diffraction(XRD)and equilibrium density have calculated and acceptable results have obtained.展开更多
基金supported by the National Science and Technology Planning Project(No.2011BAC08B00)the National High Technology Research and Development Program of China(863 Program)(No.2012AA03A611)
文摘In this paper, poly（amide-6-b-ethylene oxide） （Pebax1657）/SAPO-34 mixed matrix membranes （MMMs） were prepared by solvent-evaporation method with acetic acid as a novel solvent. CO2, N2, CH4 and H2 permeation properties were investigated, and the physical properties of Pebax/SAPO-34 MMMs were characterized by XRD and SEM. At low SAPO-34 content, it was homogeneously distributed in the Pebax ma- trix, and then precipitated and agglomerated at high SAPO-34 content. The crystallinity of Pebax phase in Pebax/SAPO-34 MMMs decreased initially and then rebounded as a result of phase separation. With the increase of transmembrane pressure difference, CO2 permeability was en- hanced due to the effect of pressure-induced plasticization. Owing to the happening of stratification, the CO2 permeability of Pebax/SAPO-34 MMMs （50 wt% SAPO-34） increased to 338 Barrer from 111 Barrer of pristine Pebax, while the selectivities of CO2/CH4 and CO2/N2 were almost unchanged. Compared with the pristine Pebax, the gas separation performances of Pebax/SAPO-34 MMMs were remarkably enhanced.
基金funded by National Natural Science Foundation of China(22278023)Beijing Municipal Science and Technology Planning Project(Z221100002722002)+1 种基金Beijing Natural Science Foundation(2222015)the long-term from the Ministry of Finance and the Ministry of Education of China.
文摘Zeolitic imidazolate framework-8(ZIF-8)is a typical filler used to fabricate mixed matrix membranes(MMMs)on account of its attractive advantage of high selective permeability for gas separation.However,the performance is usually affected by filler aggregation due to strong interactions among fillers and weak interactions between the polymer and fillers,However,the performance is usually affected by filler aggregation due to strong interactions among fillers and weak interactions between the polymer and fillers,which will lead to a decrease of selectivity and the performance of gas separation will be strongly influenced.Herein,we modified ZIF-8 with 3-amino-1,2,4-triazole to obtain ZIF-8-NH_(2),Kapton polyamide acid was selected as the polymer matrix.Results showed that the ZIF-8-NH_(2)/Kapton MMMs has a good compatibility interface between ZIF-8 and Kapton because of the covalent bridging,even the filler loading up to 45%(mass).The 45%(mass)of ZIF-8-NH_(2)/Kapton membrane showed 297 barrer(1 barrer=10^(-10)10 cm^(3)·cm·cm^(-2)·s^(-1)·cmHg^(-1),1 cmHg=1333.22 Pa,standard temperature and pressure)of the permeability of H_(2)and 43.9 and 62.2 of selectivities for H_(2)/N_(2)and for H_(2)/CH_(4),respectively,which are beyond the upper limit of Robeson 2008.
文摘Nowadays,mixed matrix membranes(MMMs)have considered by many researchers to overcome the problems of polymeric membranes.In addition,molecular dynamics(MD)and Monte Carlo(MC)simulation Methods are suitable tools for studying transport properties and morphology in MMMs.For this purpose,in this study using material studio 2017(MS)software,the transport properties of CO2,CH4 and N2 in Pebax,Psf neat Pebax/Psf composite and Pebax/Psf composite filled with ZIF-90 particles have been investigated.By adding Psf to Pebax matrix,the selectivity of CO2/CH4 and CO2/N2 gases has significantly increased.In addition,adding ZIF-90 particles to the Pebax/Psf composite increased the permeability of CO2,CH4 and N2 compared to neat and composite membranes.The morphological properties of the membranes,such as the fractional free volume(FFV),radial distribution function(RDF),glass transition temperature(TG),X-ray diffraction(XRD)and equilibrium density have calculated and acceptable results have obtained.
