Zeolite membrane with orientation-controlled hexagonal crystals from a mesostructured gel supported on γ-Al2O3

The crystals well oriented zeolite membranes were synthesized by the vapor-phase transformation (VPT) of the mesostructured gel coated and spinning on γ-Al2O3 substrate and characterized by a series of techniques such as XRD, SEM, TEM and elemental analysis. It is shown that the orientation of crystals can be controlled by variation of synthesis atmosphere and the compactness and the thickness of the membrane can be tailored by variation of the coating method and the number of coated layers. The gas separation performances of synthesized membranes have been evaluated. The selectivity of C3H8/O2 of membrane obtained by dip coating is much higher than that by spin coating due to the difference in compactness of these membranes.