Silicalite-1 zeolite membranes were prepared using the modified secondary growth method, in which titanium sol was used as a substitute of water to disperse the zeolite seed crystals. Effects of content of seed crystal in the seed suspension, number of dip-coating times and mole ratio of water to silicon on properties of the Silicalite-1zeolite membranes were investigated. XRD, SEM and single-gas permeation test were used to characterize the prepared membranes. The surfaces of the prepared membranes were continuous and dense without obvious defects. The Silicalite-1 zeolite layer and the porous support were well-knitted comparing with conventional secondary growth method. Single-gas permeation tests indicated that at 323K, with a 0.1MPa pressure drop, the permeance of H2 and H2/SF6 ideal separation factor of the obtained membrane reached a high level of 7.36 x 10-7mol/m2sPa and 28.6, respectively.

Preparation of Silicalite-1 Zeolite Membrane on Porous α-Al2O3 Tube by Modified Secondary Growth Method and its Characterization. W.Xiao, J.Yang, H.Wu, J.Wang: Petrochemical Technology, 2009, 38[5], 497-503