Effect of Fe doped over V–Sb oxide catalyst in toluene selective oxidation

✍ Scribed by Adriana Romero; Beatriz Irigoyen; Susana Larrondo; Silvia Jacobo; Norma Amadeo

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 472 KB
• Volume: 133-135
• Category: Article
• ISSN: 0920-5861
• DOI: 10.1016/j.cattod.2007.11.030

✦ Synopsis

Mixed oxides Fe x V 1Àx SbO 4 with x = 0-1.0 were prepared by slurry method and characterized by X-ray diffraction (XRD), Mo ¨ssbauer spectroscopy, and temperature-programmed reduction (TPR). The samples with x = 0, 0.4 and 1.0 were evaluated as catalyst in vapor phase toluene partial oxidation reaction. It was found by XRD that Fe, as doping, was introduced in the rutile structure of VSbO 4 . The BET surface area of partially substituted solid with x = 0.4 was higher than those obtained for VSbO 4 and FeSbO 4 samples. It was shown that V is responsible of the hydrocarbon molecule activation. The catalyst with Fe x = 0.4 presented lower specific rate reaction and lower selectivity to total oxidation products than undoped solid (VSbO 4 ), which it would be related to a partial replace of V by Fe in the V-O-V chains.

In conclusion, the solid activity and selectivity to total oxidation decrease due to a higher isolation of V sites, when V 3+ is substituted by Fe 3+ in the rutile structure.