Propylene Production via Oxidative Dehydrogenation of Propane with Carbon Dioxide over Composite M x O y -TiO 2 Catalysts

• Published in: Nanomaterials (Basel, Switzerland) Vol. 14; no. 1
• Main Authors: Florou, Alexandra, Bampos, Georgios, Natsi, Panagiota D, Kokka, Aliki, Panagiotopoulou, Paraskevi
• Format: Journal Article
• Language: English
• Published: Switzerland 28.12.2023
• Subjects: surface basicity; Ce; Zr; composite metal oxides; oxidative dehydrogenation of propane with CO2; Ga; Ca; Cr; TiO2
• ISSN: 2079-4991; 2079-4991

The CO -assisted oxidative dehydrogenation of propane (ODP) was investigated over titania based composite metal oxides, 10% M O -TiO (M: Zr, Ce, Ca, Cr, Ga). It was found that the surface basicity of composite metal oxides was significantly higher than that of bare TiO and varied in a manner which depended strongly on the nature of the M O modifier. The addition of metal oxides on the TiO surface resulted in a significant improvement of catalytic performance induced by a synergetic interaction between M O and TiO support. Propane conversion and propylene yield were strongly influenced by the nature of the metal oxide additive and were found to be superior for the Cr O -TiO and Ga O -TiO catalysts characterized by moderate basicity. The reducibility of the latter catalysts was significantly increased, contributing to the improved catalytic performance. This was also the case for the surface acidity of Ga O -TiO which was found to be higher compared with Cr O -TiO and TiO . A general trend was observed whereby catalytic performance increased significantly with decreasing the primary crystallite size of TiO . DRIFTS studies conducted under reaction conditions showed that the adsorption/activation of CO was favored on the surface of composite metal oxides. This may be induced by the improved surface basicity observed with the M O addition on the TiO surface. The Ga O containing sample exhibited sufficient stability for about 30 h on stream, indicating that it is suitable for the production of propylene through ODP with CO reaction.