Molybdate/Antimonate as Key Metal Oxide Catalysts for Acrolein Ammoxidation to Acrylonitrile

Acrylonitrile, a large tonnage chemical used in the polymer industry, may be produced by ammoxidation of acrolein, the latter being possibly obtained by glycerol dehydration. This would provide a green acrylonitrile synthesis as compared to the present industrial practice which involves ammoxidation of propylene (or propane) of fossil origin. Traditionally, antimonate and molybdate based catalysts are used for propylene ammoxidation to acrylonitrile, and these catalysts should be also active for acrolein conversion. In this work, we report a simple method for synthesis of mixed antimonate and molybdate with various molar ratios supported on mesostructured silica in order to obtain highly porous and high specific surface area materials. The results indicate that molybdenum oxide plays a major role for the acrolein ammoxidation compared to antimony oxide. Acrolein conversion and acrylonitrile selectivity were reduced with increasing fraction of antimony oxide in the mixture. The catalysts were characterized by N 2 physisorption, X-ray diffraction, Raman spectroscopy, thermal gravimetric analysis, inductively coupled plasma, transmission electron microscopy, X-ray photoelectron spectroscopy, and catalytic tests. Graphical Abstract