PROCESS FOR PRODUCING ACRYLIC ACID

摘要

A process for producing acrylic acid, characterized by subjecting to azeotropic dehydration an acrylic-acid-containing liquid oxidation product obtained by catalytic vapor-phase oxidation to obtain crude acrylic acid, regulating the total concentration of maleic acid and maleic anhydride in the crude acrylic acid to 2,000 ppm or lower, and then distilling the crude acid in the presence of a hydrazine compound. The process enables high-purity acrylic acid to be economically produced from crude acrylic acid obtained by the catalytic vapor-phase oxidation method, while sufficiently removing impurities such as aldehydes, ketones, maleic acid, and the like and inhibiting sludge generation.