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7728279 
Journal Article 
Seeding on the synthesis of MCM-22 (MWW) zeolite by dry-gel conversion method and its catalytic properties on the skeleton isomerization and the cracking of hexane 
Saha, SK; Komura, PK; Kubota, Y; Sugi, Y 
2005 
1 
Materials Transactions
ISSN: 1345-9678 
JAPAN INST METALS 
SENDAI 
46 
12 
2651-2658 
English 
WOS:000234846500020 
The effects of seeding on synthesis of MCM-22 (MWW) have been studied by the dry gel conversion (DGC) method. Highly reproducible crystalline MWW zeolite could be obtained by DGC method, using seeds of calcined sodium MWW with SiO2Al2O3 = 31. Crystallization of MWW phase was completed in the presence of seeds (2 mass% against SiO2) at 150°C within two days. The small amount of seed (0.25 mass% against SiO 2) was sufficient for the required phase formation of MWW. The MWW with SiO2/Al2O3 ratio from 35 to 66 was obtained as pure phase; however, the crystallinity of MWW decreased with further increase in the ratio: products were contaminated with impurities. The catalytic properties of MWW were examined in the skeleton isomerization and the cracking of hexane, and compared to zeolites such as BEA, MFI, and MOR. The catalytic activities were in the order: MFI>BEA>MWW»MOR; however, the selectivity for the isomerization were in the order: BEA>MWW>MFI. These catalytic properties were due to the differences of structures and acid strength of zeolites. © 2005 The Japan Institute of Metals. 
MCM-22 (MWW); dry-gel conversion (DGC) seeds; skeleton isomerization of hexane; cracking 
7th International Conference on Ecomaterials 
Singapore, SINGAPORE