METHOD FOR PRODUCING AQUEOUS (METH)ACRYLIC ACID

PROBLEM TO BE SOLVED: To provide a method for producing aqueous (meth)acrylic acid containing impurities and by-products in more reduced amounts, while needing only less processes and apparatuses than those of known separation methods. SOLUTION: Provided is the method for producing the aqueous (meth)acrylic acid containing formaldehyde in an amount of ≤0.1 wt.%, comprising feeding a (meth)acrylic acid-containing gaseous substance flow 10 into a condenser column 12, cooling a gaseous substance 24 exhausted from an overhead portion 26 with an outer heat exchanger 16 to divide into a condensed flow 28 returning to the column and a residual exhaust gas 20, making the condensed product into contact with a supplied gas in the column, and then extracting the aqueous (meth)acrylic acid 18 from the column bottom 22. The (meth)acrylic acid-containing gaseous substance flow may be a flow of a product produced by catalytically oxidizing at least one 2-4C alkane or alkene. COPYRIGHT: (C)2010,JPO&INPIT