Abstract: In order to investigate the method to produce NaA molecular sieve in large scale,the fine-crystal NaA molecular sieve was prepared by grinding method using NaA zeolite as raw materials and NaCl as grinding aids.The phase composition,morphology,particle distribution and surface area of NaA molecular sieve before and after grinding were characterized by SEM,BET,and Laser Particle Size Analyzer,and Cd2+ exchange capacity was determined.The results showed that the particle size of NaA molecular sieve was decreased from 3 μm to 0.98 μm,the surface area was increased from 12.306 m2/g to 27.997 m2/g,and Cd2+ exchange capacity was enhanced from 294 mg/g to 352 mg/g after grinding under conditions of rotating speed 400 r/min,w(NaCl)∶w(NaA) of 12∶1,mass ratio between ball and powder 7∶1 for 7 h.Therefore,the dry grinding method is a novel method for mass production of NaA molecular sieve,with easy operating and low cost.

Key words: Fine-crystal NaA molecular sieve, Grinding method, NaCl, Grinding aids