Operando Molecular Spectroscopy During Ethylene Polymerization by Supported CrO x /SiO 2 Catalysts: Active Sites, Reaction Intermediates, and Structure-Activity Relationship
作者： Anisha Chakrabarti , Maciej Gierada , Jaroslaw Handzlik , Israel E. Wachs
DOI: 10.1007/S11244-016-0546-6
关键词:
摘要: Time-resolved operando molecular spectroscopy was applied during ethylene polymerization by supported CrO x /SiO2 catalysts to investigate the structure-activity relationships for this important industrial catalytic reaction. A combination of spectroscopic techniques (Raman, UV–Vis, XAS, DRIFTS and TPSR) allows first time monitor events taking place activation establishment Based on complementary DFT computational studies, a new initiation mechanism is proposed. During reaction, initial surface Cr+6O sites reduce Cr+3 form Cr–(CH2)2CH=CH2 Cr–CH=CH2 reaction intermediates with latter representing active site.
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