摘要 |
In the preparation of acrylonitrile or methacrylonitrile by ammoxidation of propylene or isobutylene with ammonia and molecular oxygen in the vapor phase in the presence of a catalyst comprising silica and supported thereon oxides of molybdenum, bismuth and iron, the yield of acrylonitrile or methacrylonitrile based on ammonia is improved without sacrificing the yield based on propylene or isobutylene by the use of a novel catalyst having, incorporated therein, 0.002 to 0.2 atom, based on 12 atoms of molybdenum, of an oxide of at least one element selected from the group consisting of palladium, platinum, osmium and iridium. |