NaA zeolite membranes were prepared by secondary growth method using ball-milled NaA particles with submicron size. Three average particle sizes (similar to 0.3 mu m, similar to 0.5 mu m and similar to 1 mu m) were obtained by ball-milling treatment of NaA zeolite powders (similar to 2.8 mu m) with a high-energy ball mill. The effect of ball-milled seeds on membrane growth was investigated. It was found that the small size and defective surface for the ball-milled seeds accelerated the growth of NaA zeolite membrane. Compared with original NaA zeolite seeds, the ball-milled seeds can induce well-intergrown NaA zeolite membranes with large reduction of synthesis time. High-quality NaA zeolite membranes were synthesized at 373-383 K for 4 h using the milled seeds with an average particles size of similar to 0.3 mu m, which showed a permeation flux of similar to 2.6 kg m(-2) h(-1) and water/ethanol separation factor of >10,000 for separating 90: 10 (wt.%) ethanol/water mixture at 343 K. (C) 2011 Elsevier B.V. All rights reserved.