Selective oxidation of propane over alkali-doped Mo-V-Sb-O catalysts

[EN] Alkali metal-doped MoVSbO catalysts have been prepared by impregnation of a MoVSbO-mixed oxide (prepared previously by a hydrothermal synthesis) and finally activated at 500 or 600 degrees C in N-2. The catalysts have been characterized and tested for the selective oxidation of propane and propylene. Alkali-doped catalysts improved in general the catalytic performance of MoVSbO, resulting more selective to acrylic acid and less selective to acetic acid than the corresponding alkali-free MoVSbO catalysts. However, the specific behaviour strongly depends on both the alkali metal added and/or the final activation temperature. At isoconversion conditions, catalysts activated at 600 degrees C present selectivity to acrylic acid higher than that achieved on those activated at 500 degrees C, both K-doped catalysts presenting the highest yield to acrylic acid. The changes in the number of acid sites as well as the nature of crystalline phases can explain the catalytic behaviour of alkali-doped MoVSbO catalysts. (C) 2008 Elsevier B.V. All rights reserved.Financial support from DGICYT in Spain through Project CTQ2006-09358/BQU is gratefully acknowledged.Ivars Barceló, F.; Solsona Espriu, BE.; Botella Asuncion, P.; Soriano Rodríguez, MD.; López Nieto, JM. (2009). Selective oxidation of propane over alkali-doped Mo-V-Sb-O catalysts. Catalysis Today. 141(3-4):294-299. doi:10.1016/j.cattod.2008.07.002S2942991413-