Patent AT-E400544-T1: [Translated] IMPROVED METHOD FOR PRODUCING A (METH)ACRYL HYDRIDE

The present invention relates to an improved method for manufacturing (meth)acrylic anhydride by transanhydrization between (meth)acrylic acid and acetic anhydride, in the presence of air and in the presence of at least one polymerization inhibitor, characterized in that the polymerization inhibitor is chosen from the group formed from (a) metal salts of thiocarbamic or dithiocarbamic acid and their mixtures with a phenolic derivative or phenothiazine and its derivatives, and (b) N-oxyl compounds as a mixture with 2,6-di-tert-butyl-4-methylphenol taken alone or in the presence of 2,4-dimethyl-6-tert-butylphenol.