Catalytic dense membranes of doped Bi4V2O11 (BIMEVOX) for selective partial oxidation: chemistry of defects versus catalysis

Axel Löfberg (1) , Hervé Bodet (1) , Caroline Pirovano (1) , Marlu César Steil (1) , Rose-Noëlle Vannier (1) , Elisabeth Bordes-Richard (1)

1 UCCS - Unité de Catalyse et Chimie du Solide - UMR 8181

A catalytic dense membrane reactor (CDMR) is used to physically separate the reaction step from the reoxidation of the catalyst. By decoupling the redox mechanism prevailing in mild oxidation of hydrocarbons, the operating conditions may be optimized resulting in an increase of selectivity. The membranes are made up of BIMEVOX oxides, obtained by partial substitution of V in Γ-Bi4V2O11 by ME (Co, Cu, Ta). Experiments performed on BIMEVOX dense membranes using propene and propane are described in terms of, (i) active sites on polished or unpolished surfaces, (ii) operating conditions (T, pO2 in the high oxygen partial pressure compartment), which determine the selectivity, either to mild oxidation products (acrolein, hexadiene, CO), or to partial oxidation products (CO, H2), and, (iii) nature of ME cations and relative properties. The discussion deals with the respective role of electronic vs. oxide ion conductivities which depend on defects in the structure as well as on the redox properties of cations.

Mots clés: catalytic dense membrane reactor; syngas; mild oxidation of propene; partial oxidation of propane; oxide ion conductivity; electronic conductivity

Domaines: Catalyse

Axel Löfberg, Hervé Bodet, Caroline Pirovano, Marlu César Steil, Rose-Noëlle Vannier, et al.. Catalytic dense membranes of doped Bi4V2O11 (BIMEVOX) for selective partial oxidation: chemistry of defects versus catalysis. Topics in Catalysis, 2006, 38, pp.169-179. ⟨10.1007/s11244-006-0082-x⟩. ⟨hal-00104262⟩