Effects of Seeding on the Formation of Large NaX Zeolite Crystals

Abstract:

The problem with zeolite crystals synthesized by conventional methods is that they are extremely small: their size typically varies 2 and 8 µm, To better define the structure of a zeolite, scientists need to grow crystal that are 100 to 1000 times larger. In this work, large crystals zeolite NaX with a uniform size of 50µm were grown by a continuous crystallization method from seed crystals (5-10µm) formed in a mother solution with the 3.5Na2O : Al2O3 : 2.1SiO2 : 1000H2O composition. In order to grow zeolite NaX crystals to an appropriate size by the continuous method, the mother solution was fed into an autoclave a solution with various seed contents (3 - 20wt%); the autoclave has at 90°C and the solution was added after 7, 12, 16, 19 and 24 days or at 100°C after 7 and 9 days.

• Periodical: Materials Science Forum (Volumes 492-493)
• Pages: 287-292
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.492-493.287
• Online since: August 2005
• Authors: Ik Jin Kim, Hae Jin Lee
• Keywords: Crystallization, Homogeneity, Large Crystal, NaX Zeolite, Nucleation, Seed

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