11-Molybdo-1-vanadophosphoricacid H4PMo11VO40 supported on ammonia-modified silica as highly active and selective catalyst for oxidation of methacrolein

Gas-phase oxidation of methacrolein to methacrylic acid has been carried out over various unsupported and supported H4PMo11VO40 catalysts. While SiO2-supported H4PMo11VO40showed low selectivity to methacrylic acid, H4PMo11VO40 supported on NH3-modified SiO2, which was prepared by using an impregnation method with acetone as the solvent, exhibited high selectivity (~ 90%) and high activity for the formation of methacrylic acid. The activity of H4PMo11VO40/NH3-modified SiO2was more than five times higher than that of the corresponding unsupported catalysts.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Ammonia-modified SiO2 was used as a support for H4PMo11VO40. ► H4PMo11VO40 supported on ammonia-modified SiO2 exhibited high activity and selectivity for formation of methacrylic acid in the oxidation of methacrolein. ► On ammonia-modified SiO2, NH4+ salt of H4PMo11VO40 was formed and this was stable under the reaction conditions.