Effects of seeding on large crystal growth of NaX zeolite by continuous crystallisation

Abstract

The problem with zeolite crystals synthesized by conventional method is that they are extremely small of two to eight microns, To better define the structure of zeolite, scientist need to grow crystal that are 100 to 1000 times larger. In this work, Large crystal zeolite X of uniform crystal size of 50mum were grown by a continuous crystallization method from seed crystals (5-10mum) in a mother solution having a composition 3.5Na(2)O: Al2O3: 2.1SiO(2): 1000H(2)O. In order to grow crystals of zeolite X to an appropriate size by the continuous method, the mother solution was supplied into the starting solution with various seed content (3similar to20wt%) in an autoclave at 90degreesC after 7 days, 12days, 16days, 19days and 24 days, respectively.