Reactive Extraction for Downstream Separation of 1,3-Propanediol

The downstream separation of 1,3-propanediol from dilute aqueous solution was studied. A process combining reversible reaction of 1,3-propanediol with acetaldehyde to 2-methyl-l,3-dioxane and a simultaneous extraction of the product by organic solvent appears to be technically feasible and attractive. The dioxane yield was 91-92%, the overall conversion of 1,3-propanediol was ca. 98%, and recovery of dioxane into the organic extractant was 75%.