Patent ID: 6972346
Filing Date: 2005-12-06
Classification: C07C

Abstract:
1. A process for producing 1,3-propanediol comprising the steps of: a) forming an aqueous solution of 3-hydroxypropanal, b) hydrogenating the 3-hydroxypropanal to form a first crude 1,3-propanediol mixture comprising 1,3-propanediol, water, and MW 132 cyclic acetal, c) distilling the first crude 1,3-propanediol mixture to remove water and low boiling impurities and form a second crude 1,3-propanediol mixture, d) contacting the second crude 1,3-propanediol mixture with an acid form cationic exchange resin at a temperature of from about 50 to about 150° C. to convert the MW 132 cyclic acetal to more volatile cyclic acetals and/or other degradation products, and e) separating the more volatile cyclic acetals and/or other degradation products from the 1,3-propanediol by distillation or gas stripping.