Process for the production of diacyl peroxides

A process for the production of a diacyl peroxide comprising the following steps:

• a) producing a mixture comprising a diacyl peroxide and a carboxylic acid by reacting an anhydride with the formula R1—C(═O)—O—C(═O)—R2 with a peroxyacid of the formula R3—C(═O)—OOH,
• wherein R1 and R3 are independently selected from linear and branched alkyl, cycloalkyl, aryl, and arylalkyl groups, each with 1 to 17 carbon atoms, optionally substituted with oxygen- and/or halogen-containing substituents, and R2 is selected from linear and branched alkyl, cycloalkyl, aryl, and arylalkyl groups, each with 2 to 17 carbon atoms, optionally substituted with oxygen- and/or halogen-containing substituents,
• b) extracting or separating the carboxylic acid from the mixture in the form of its carboxylic acid salt or adduct,
• c) liberating the carboxylic acid from the salt or adduct,
• d) optionally producing an additional amount of carboxylic acid by reacting an aldehyde of the formula R2—C(═O)H with oxygen,
• e) reacting the carboxylic acid obtained in step c) and optionally an additional amount of carboxylic acid of the formula R2—C(═O)OH—said additional amount of carboxylic acid being obtained from step d) and/or obtained in another way—with an acid anhydride or a ketene of the formula C(R4)2═C═O, each R4 being independently selected from H and CH3 to form an anhydride with the formula R1—C(═O)—O—C(═O)—R2, and
• f) recycling at least part of the anhydride formed in step e) to step a).