Abstract：The influence of gel alkalinity on the synthesis of zeolite P and its membrane was examined in detail, which show the decisive effect of gel alkalinity on the structure of the zeolite synthesized and the optimum gel alkalinity for the synthesis of zeolite P is given. Zeolite P membranes were hydrothermally synthesized in situ on the outer surface of a porous a-Al2O3 support tube with a length of 25 cm and pore size of 3~5 mm. XRD and SEM characterization of the as-synthesized membrane show that the as-synthesized membrane is a typical zeolite P membrane, with no apparent defects on the membrane surface, where the zeolite crystals grow interlinkedly and compactly, and that the outer surface of the support tube is completely covered with P crystal layers with a thickness of about 10~12 mm. At 25oC, H2 and N2 single component permeation tests of the as-synthesized membrane give the permeability up to 10-6 magnitude and the H2/N2 selective factor between 3.19~3.33.
2004, Vol. 4 
