Synthesis and gas separation performance of zeolite membranes with orientation-controlled hexagonal crystals supported on γ-Al2O3

摘要

Zeolite membranes with the well oriented crystals were synthesized by the vapour phase transformation (VPT) of the mesostructured gel coated and spinning on -Al2O3 substrate and characterized by a series of techniques such as XRD, SEM and elemental analysis. It is shown that the orientation of crystals can be controlled by variation of synthesis atmosphere. The compactness and the thickness of the membrane can be tailored by variation of the coating method and the number of coated layers. It is very important to indicate that the alumina flat used played not only the role of the support for membrane growth, but also was used as Al source supplier to guarantee the formation of a silicoaluminate zeolite. 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.