T. Takewaki, L. Beck, Mark E. Davis
Dec 15, 1999
Citations
0
Influential Citations
25
Citations
Journal
Microporous and Mesoporous Materials
Abstract
Abstract A number of 1,4-diazabicyclo[2,2,2]octane (DABCO) derivatives are used as structure-directing agents in high-silica, zeolite syntheses in the presence and absence of Al 3+ , B 3+ and Zn 2+ . Several high-silica products including phases with unknown structure are synthesized. The results suggest that the product selectivity can be influenced by methyl-substitution of the DABCO moiety. However, when using DABCO-polymers, the number of methylene carbon atoms between the DABCO units rather than methyl-substitution of DABCO has the largest effect on the final products formed. 13 C-CP MAS NMR results show that the signal attributed to the carbon atoms in the DABCO unit in both a DABCO polymer and 1,4-diazoniabicyclo[2,2,2]octane,1,4-dimethyl are split into two signals when these organics are guests in zeolites. The data suggest that the ionic interactions between two cation sites of the DABCO unit and the zeolite framework are different.