| With gradual decreasing of petroleumresources, it is more and more essential and urgent to develop an energy-conserving and high-efficient production technology of fuel ethanol. Silicalite-1 Zeolite membrane with well crystalline structures, built-in hydrothermal and chemical stabilization, especially it's hydrophobic capability can be expected to apply in pervaporation process, which can selectively permeate ethanol. The purpose of this study is to prepare such a silicalite zeolite membrane with good performance.Nano-sized silicalite-1 zeolite crystals with uniform size were synthesized using TPAOH solution as a template and TEOS as a Si source in a clear synthesis solution. The ultimate crystal size is ranging from approximate 180nm to 6μm. Factors influencing particle size and habit have been investigated, including aging time, reaction temperature and other conditions. The effect of seeds was discussed when applying in seeding.Seeded growth methods have been used to prepare intact Sil-1 zeolite membrane on a-alumina support with a average pore diameter of 5μm. Flux of H2 in single gas permeation is 8.6×10-7 mol·m-2·s-1·Pa-1. Separation factor of H2 to SF6 is 72. Reaction time, temperature and recipe were investigated. Different seeds have been used to prepared better membranes. The results showed that membranes prepared using seeds of approximate 500nm had the best separation performance.Pervaporation of an aqueous ethanol solution with 5wt％ethanol were used to test membranes prepared at different conditions. The best separation factor is 51.
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