Preparation of Composite Microporous Silica Membranes Using TEOS and 1,2-Bis(triethoxysilyl)ethane as Precursors for Gas Separation  

以正硅酸乙酯和1,2-二(三乙氧基硅基)乙烷为前驱体制备微孔Si0_2复合膜及其气体分离性能(英文)

作　　者：漆虹 

机构地区：[1]Membrane Science and Technology Research Center,State Key Laboratory of Materials-Oriented Chemical Engineering,Nanjing University of Technology

出　　处：《Chinese Journal of Chemical Engineering》2011年第3期404-409,共6页中国化学工程学报（英文版）

基　　金：Supported by the National Natural Science Foundation of China(20906047);the State Key Laboratory of Chemical Engineering(SKL-ChE-09A01);the State Key Laboratory of Materials-Oriented Chemical Engineering(ZK201002)

摘　　要：This paper reports on a new microporous composite silica membrane prepared via acid-catalyzed polymeric route of sol-gel method with tetraethylorthosilicate(TEOS)and a bridged silsesquioxane[1,2-bis(triethoxysilyl)ethane, BTESE]as precursors.A stable nano-sized composite silica sol with a mean volume size of^5 nm was synthesized. A 150 nm-thick defect-free composite silica membrane was deposited on disk support consisting of macroporous α-Al2O3 and mesoporousγ-Al2O3 intermediate layer by using dip-coating approach,followed by calcination under pure nitrogen atmosphere.The composite silica membranes exhibit molecular sieve properties for small gases like H2,CO2,O2,N2,CH4 and SF6 with hydrogen permeances in the range of(1-4)×10 -7mol·m -2·s -1·Pa -1(measured at 200°C,3.0×105 Pa).With respect to the membrane calcined at 500°C,it is found that the permselectivities of H 2 (0.289 nm)with respect to N2(0.365 nm),CH4(0.384 nm)and SF6(0.55 nm)are 22.9,42 and>1000,respectively, which are all much higher than the corresponding Knudsen values(H2/N2=3.7,H2/CH4=2.8,and H2/SF6=8.5).This paper reports on a new microporous composite silica membrane prepared via acid-catalyzed polymeric route of sol-gel method with tetraethylorthosilicate（TEOS）and a bridged silsesquioxane[1,2-bis（triethoxysilyl）ethane, BTESE]as precursors.A stable nano-sized composite silica sol with a mean volume size of^5 nm was synthesized. A 150 nm-thick defect-free composite silica membrane was deposited on disk support consisting of macroporous α-Al2O3 and mesoporousγ-Al2O3 intermediate layer by using dip-coating approach,followed by calcination under pure nitrogen atmosphere.The composite silica membranes exhibit molecular sieve properties for small gases like H2,CO2,O2,N2,CH4 and SF6 with hydrogen permeances in the range of（1-4）×10 -7mol·m -2·s -1·Pa -1（measured at 200°C,3.0×105 Pa）.With respect to the membrane calcined at 500°C,it is found that the permselectivities of H 2 （0.289 nm）with respect to N2（0.365 nm）,CH4（0.384 nm）and SF6（0.55 nm）are 22.9,42 and1000,respectively, which are all much higher than the corresponding Knudsen values（H2/N2=3.7,H2/CH4=2.8,and H2/SF6=8.5）.

关 键 词：TETRAETHYLORTHOSILICATE 1 2-bis（triethoxysilyl）ethane composite silica membranes gas separation mo- lecular sieving 

分 类 号：TQ028.8[化学工程] TN304.21[电子电信—物理电子学]