Patent ID: 7041849
Filing Date: 2006-05-09
Classification: C07C

Abstract:
1. A method of recovering a polymerization inhibitor from a liquid that comprises the polymerization inhibitor, the liquid being discharged in an acrylic acid production process, the acrylic acid producing process comprising the steps 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, the liquid being a residue discharged in the step of purifying, wherein the method comprises the steps of: adjusting a viscosity at 20° C. of the liquid to 2Pa·s (2,000 cP) or less; and extracting the polymerization inhibitor from the liquid by using an aqueous medium.