Abstract: High-performance LTA zeolite membranes were synthesized on tubular supports by a modified in situ synthesis strategy. The preparation by conventional heating (CH) and microwave heating (MH) was studied. Both CH- and MH-synthesized membranes showed high dehydration performance toward 95.0% isopropanol/water mixtures. However, when the water content in the feed was lower than 2.0%, the CH-synthesized membrane had no separation ability any more. This is due to the existence of nano-sized non-zeolite pores in the zeolite membranes. These defects could be eliminated mostly using fast and homogenous MH.

Key words: LTA zeolite, zeolite membrane, non-zeolite pore, defect, microwave, pervaporation