Molybdenum oxide based partial oxidation catalyst: 4. TEM identification of a new oxygen-reduced phase formed during acrolein partial oxidation under reducing conditions

✍ Scribed by Y Uchida; G Mestl; O Ovsitser; J Jäger; A Blume; R Schlögl

• Book ID: 104421989
• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 265 KB
• Volume: 187
• Category: Article
• ISSN: 1381-1169
• DOI: 10.1016/s1381-1169(02)00211-x

✦ Synopsis

A new Mo-based structure was detected by high resolution transmission electron microscopy (HRTEM) and electron diffraction techniques in a molybdenum based mixed oxide catalyst after operation in the partial oxidation of acrolein at temperatures between 533 and 573 K for 9 h. This new crystalline phase has an orthorhombic crystal system. The structure has presumably a space group of Pban, but Pmmn cannot be excluded. XRD analysis was further used to refine this new Mo 2 O 5 structure. The lattice constants were estimated to be a = 1217.5, b = 374.7 and c = 404.4 pm, respectively. The elemental composition of the crystal was determined by the EDAX system attached to the electron microscope to be about (Mo 0.6 V 0.3 W 0.1 ) 2 O 5-x . This new structure is discussed in relation to earlier reports on a comparable composition and with respect to its possible role for partial oxidation catalysis.