Polymerization on CO-Reduced Phillips Catalyst initiates through the C–H bond Activation of Ethylene on Cr–O Sites
作者： Murielle F. Delley , Matthew P. Conley , Christophe Copéret
DOI: 10.1007/S10562-014-1238-0
关键词: Photochemistry 、 Polymer chemistry 、 Phillips catalyst 、 Chemistry 、 Heterolysis 、 Infrared spectroscopy 、 Chromium 、 Heterogeneous catalysis 、 Polymerization 、 Ethylene 、 Catalysis
摘要: Investigation of the polymerization ethylene on CO-reduced Phillips catalyst (1 wt% chromium) by infrared spectroscopy reveals presence new OH bands. In particular, an OH-band appears at 3,605 cm−1, consistent with interaction SiOH group adjacent Lewis acidic chromium center, Si–(μ-OH)–Cr. Polymerization d4-ethylene leads to formation isotopically shifted band 2,580 cm−1, heterolytic C–H activation over a Cr–O bond generate first Cr–C in catalyst, as recently observed well-defined Cr(III) silicates.
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sci-hub.se 参考文章(35)
Raphael Wischert, Christophe Copéret, Françoise Delbecq, Philippe Sautet, Optimal water coverage on alumina: a key to generate Lewis acid-base pairs that are reactive towards the C-H bond activation of methane. Angewandte Chemie. ,vol. 50, pp. 3202- 3205 ,(2011) , 10.1002/ANIE.201006794
D MYERS, Silica-supported chromium catalysts for ethylene polymerization: The active oxidation states of chromium Journal of Catalysis. ,vol. 99, pp. 140- 148 ,(1986) , 10.1016/0021-9517(86)90207-1
E. Groppo, C. Lamberti, S. Bordiga, G. Spoto, A. Zecchina, The structure of active centers and the ethylene polymerization mechanism on the Cr/SiO2 catalyst: a frontier for the characterization methods. Chemical Reviews. ,vol. 105, pp. 115- 183 ,(2005) , 10.1021/CR040083S
V. J. Ruddick, J. P. S. Badyal, EARLY STAGES OF ETHYLENE POLYMERIZATION USING THE PHILLIPS CROX/SILICA CATALYST Journal of Physical Chemistry B. ,vol. 102, pp. 2991- 2994 ,(1998) , 10.1021/JP963318F
Bert M Weckhuysen, Robert A Schoonheydt, Alkane dehydrogenation over supported chromium oxide catalysts Catalysis Today. ,vol. 51, pp. 223- 232 ,(1999) , 10.1016/S0920-5861(99)00047-4
L PRZHEVALSKAYA, The study of active centers of ethylene polymerization over chromium catalysts prepared from tri- and bivalent chromium compounds Journal of Catalysis. ,vol. 39, pp. 363- 368 ,(1975) , 10.1016/0021-9517(75)90302-4
Christophe Coperet, C−H Bond Activation and Organometallic Intermediates on Isolated Metal Centers on Oxide Surfaces Chemical Reviews. ,vol. 110, pp. 656- 680 ,(2010) , 10.1021/CR900122P
C GROENEVELD, P WITTGEN, A VANKERSBERGEN, P MESTROM, C NUIJTEN, G SCHUIT, Hydrogenation of olefins and polymerization of ethene over chromium oxide/silica catalystsI. Preparation and structure of the catalyst Journal of Catalysis. ,vol. 59, pp. 153- 167 ,(1979) , 10.1016/S0021-9517(79)80021-4
Øystein Espelid, Knut J. Børve, Molecular-Level Insight into Cr/Silica Phillips-Type Catalysts: Polymerization-Active Mononuclear Chromium Sites Journal of Catalysis. ,vol. 205, pp. 366- 374 ,(2002) , 10.1006/JCAT.2001.3443
Eugene You-Xian Chen, Tobin J. Marks, Cocatalysts for Metal-Catalyzed Olefin Polymerization: Activators, Activation Processes, and Structure−Activity Relationships Chemical Reviews. ,vol. 100, pp. 1391- 1434 ,(2000) , 10.1021/CR980462J