PROCESS FOR THE MANUFACTURE OF METHACRYLIC OR ACRYLIC ACID

摘要

Methacrylic acid or acrylic acid is produced by the oxidation of methacrolein or acrolein with molecular oxygen in the presence of water vapour. Present in the reaction system is a catalyst containing palladium, phosphorus, oxygen and, optionally, antimony. A phosphoric acid or a phosphorus compound capable of forming a phosphoric acid under the reaction conditions is concurrently supplied to the reaction system. The catalyst possesses good selectivity and long life even when used at high space velocities.