Synthesis and characterization of Ni-doped vanadium phosphorus oxide catalysts

The effect of Ni doping (1%, 2%, and 5%) on vanadium phosphate catalysts prepared via VOPO4·2H2O was described and discussed. At low levels, the Ni dopant significantly enhanced the amount of the active lattice oxygen species O− and lowered the reduction peak temperature corresponding to the reducti...

Full description

Bibliographic Details
Main Authors: Yap, Taufiq Yun Hin, Abdul Aziz, Abdul Ghani
Format: Article
Language:English
Published: Elsevier 2007
Online Access:http://psasir.upm.edu.my/id/eprint/7855/
http://psasir.upm.edu.my/id/eprint/7855/1/Synthesis%20and%20Characterization%20of%20Ni.pdf
Description
Summary:The effect of Ni doping (1%, 2%, and 5%) on vanadium phosphate catalysts prepared via VOPO4·2H2O was described and discussed. At low levels, the Ni dopant significantly enhanced the amount of the active lattice oxygen species O− and lowered the reduction peak temperature corresponding to the reduction of V5+ and V4+ phases. A combination of powder X-ray diffraction, temperature-programmed reduction, and chemical analysis data shows that at higher levels, Ni doping induced the formation of the V5+ phase and suppressed the presence of the V4+ phase. Previous studies have indicated that a large amount of oxygen species associated with V5+ inhibit the n-butane conversion but promote the selectivity for maleic anhydride.