Patent ID: 6596901
Filing Date: 2003-07-22
Classification: C07C

Abstract:
A process for preparing acrylic acid or methacrylic acid, comprising:(a) providing a gaseous reaction product mixture having essentially the composition of a reaction mixture of the catalytic gas phase oxidation of at least one member selected from the group consisting of C3-/C4-alkanes, alkenes, alkanols, alkanals, and precursors thereof, to form acrylic acid or methacrylic acid, (b) condensing said gaseous reaction product mixture to form a solution, (c) crystallizing acrylic acid or methacrylic acid from a solution consisting essentially of the solution obtained in step (b), to form crystals of acrylic acid or methacrylic acid and a mother liquor, and (d) removing the crystals from the mother liquor.