摘要 |
1. Catalyst based on the elements molybdenum, vanadium, phosphorus and oxygen, and optionally one or more metal ions, as acitve ingredients, preferably arranged on an inert support, for the oxidative dehydrogenation of isobutyric acid or the lower esters thereof to obtain methacrylic acid or the lower esters thereof, characterized in that the catalytically active component of the catalyst is or is formed from a vanadium -containing heteropolymolybdate mixture or phosphorusmolybdic acid, H3 PMo12 O40 or the salts thereof, and/or vanadium derivatives thereof, H3+x PMo12-x Vx O40 wherien x = 1, 2 or 3 and/or the salts thereof. |