In an acrylic acid production process which comprises the step of producing acrylic
acid by catalytic vapor-phase oxidation of propane, propylene, and/or acrolein;
and purifying the acrylic acid produced in the step of producing with distillation
in the presence of the polymerization inhibitor for preventing polymerization of
the acrylic acid, a viscosity at 20 C. of the bottoms which comprises the
polymerization inhibitor, discharged in the step of purifying, is adjusted to 2
Pas (2,000 cP) or less and the polymerization inhibitor is extracted using
an aqueous medium.
According to the method, in an acrylic acid production process, an extraction
operation for recovery of the polymerization inhibitor can be continuously conducted
in a stable manner.