PROCESS FOR PREPARING METHACRYLIC ACID

摘要

A catalyst for the oxidation of isobutyric acid to methacrylic acid in the vapor phase comprises a molybdenum-phosphorus oxide catalyst, optionally containing vanadium, supported on a porous support having a porosity of 10 to 80 % and an interior surface of less than 1 m2/g. The catalyst may optionally contain at least one metal from the first through fourth principal group or second through eighth secondary group of the periodic table. The oxidative dehydrogenation is carried out by contacting a gaseous mixture of isobutyric acid and oxygen with the catalyst at a temperature above 300.degree.C.