Continuous process for the production and purification of acrylic acid

A continuous process for the purification of acrylic acid, having the formula CH2═CH—COOH, comprising a process stage that comprises the following process steps:

• a) crystallizing acrylic acid out from a mother liquor by a continuous crystallization method;
• b) separating crystallized acrylic acid from the mother liquor in a wash column that permits continuous operation of the process, wherein the crystallized acrylic acid is washed and compacted to form a crystal bed, wherein a suspension is formed from the crystal bed and a wash melt, wherein the suspension is moved to a heat exchanger, and the mother liquor is removed from the wash column;
• c) melting at least part of the suspension from b) to form molten acrylic acid;
• and
• d) the molten acrylic acid is at least partially recycled to step a) or to step b) wherein at least part of acrylic acid is continuously removed from the process.