Patent ID: 7038079

Claim:
A method for the production of acrylic acid comprising: a step of introducing a mixed gas containing propylene and molecular oxygen into a first reactor packed with a complex oxide catalyst having molybdenum and bismuth as essential components and oxidizing propylene and obtaining an acrolein-containing gas; a step of introducing said acrolein-containing gas into a second reactor packed with a complex oxide catalyst having molybdenum and vanadium as essential components and obtaining an acrylic acid-containing gas; and a step of introducing said acrylic acid-containing gas into an acrylic acid absorption column and causing it to contact an absorbent, wherein said absorbent is introduced into said acrylic acid absorption column at a mass flow rate in the range of 0.1–1.5 times the mass flow rate of propylene introduced into said first reactor, thereby obtaining an acrylic acid-containing solution in which (a) said mixed gas for introduction into said first reactor having a propylene concentration in the range of 7–15 vol. % and a water concentration in the range of 0–10 vol. %, and (b) said acrylic acid-containing solution obtained in said acrylic acid absorption column having a water concentration in the range of 1–45 wt. %.