Indexed by:Journal Article

Date of Publication:2017-07-01

Journal:CRYSTAL GROWTH & DESIGN

Included Journals:Scopus、EI、SCIE

Volume:17

Issue:7

Page Number:3940-3947

ISSN:1528-7483

Abstract:Zeolite omega has been synthesized directly in the presence of tetramethylammonium ions (TMA(+)) by the magadiite conversion method. Using the reactive gel composition: 20SiO(2): Al2O3: 3.6Na(2)O: 180H(2)O: 0.96TMABr, pure and high crystalline zeolite omega could be obtained at 100 degrees C for 72 h. It is found that most of the long-range order structure of magadiite was retained, even though part of it was collapsed, as its primary structure during the crystallization process. Meanwhile, the crystallization behavior and changes of medium-range structure in the synthesis were characterized. The growth of zeolite omega occurs on the surface of magadlite, and 4-membered rings probably from the connection by 5-membered rings are formed after 10 h. The Al atoms prefer to occupy the position in 6-membered rings of gmelinite in zeolite omega. The influence of reaction time, temperature, and composition in starting gel was examined.