Modification of Bronsted acidity of zeolites by Ga+, GaO+ and AlO+: comparison for alkane activation
Modification of Bronsted acid sites in zeolites by Ga+, GaO+ and AlO+ ions profoundly changes the way of alkane activation. Over Bronsted acid protons propane is activated via a carbonium ion mechanism resulting in propylene, methane and ethylene as hydrocarbon products. Over Ga+ ions, heterolytic dissociation of propane takes place over the Lewis acidbase pair formed by the Ga+ ion and the zeolite oxygen anion. Propylene is now the main product. Similarly, propane gives propylene over the acid-base pair of GaO+, however, via a lower energy barrier. Regeneration of the GaO+ cation is difficult and instead Ga+ cations are generated. Finally, our work indicates that non-reducible AlO+ ions enhance the activity of the Bronsted protons for protolytic cracking.
E. J. M. Hensen E. A. Pidko N. Rane R. A. van Santen
Schuit Institute of Catalysis, Eindhoven University of Technology, Den Dolech 2, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
国际会议
北京
英文
2007-08-12（万方平台首次上网日期，不代表论文的发表时间）