COLL 414 |
| Allen Burton and Stacey Zones. Chevron Research and Technology Co, Chevron, Richmond, CA 94802 |
| A holy grail in zeolite synthesis has been the a priori prediction of zeolite phases based upon the use of particular organic structure directing agents (SDAs). In this study, we first examined a group of monoquaternary imidazolium compounds as SDAs [1]. Changes in the substituents off the imidazole ring led to specification of different zeolite structures, specifically one-dimensional pore zeolites with the MTT, TON, and MTW topologies. In order to better understand and rationalize the structure-directing effects of these molecules, we performed energy optimization calculations of the molecules within each of the pore structures. From the energy-optimized position of the N,N’-diisopropylimidazolium compound within the MTT pore structure and crystallographic considerations of the zeolite structure itself, we were able to understand the determinant properties of many other molecules that specify MTT phases. Based upon these considerations, we next predicted a large family of previously unexamined molecules of varying carbon lengths and shapes that should also yield MTT phases in zeolite syntheses. We then prepared these novel amines and used them in zeolite syntheses under three different Si/Al gel compositions. The results of the zeolite syntheses are in remarkable agreement with the predicted phases. Zones S. I., Zeolites 9 (1989) 483 |
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Ipatieff Award Symposium Honoring Raul Lobo
8:30 AM-11:30 AM, Wednesday, March 31, 2004 Marriott -- Grand Ballroom K, Oral
Division of Colloid and Surface Chemistry |