Abstract: A process for separating an alkylene oxide from an aqueous mixture is provided in which no detectable dioxane byproduct is formed. An aqueous mixture containing an alkylene oxide is contacted with a carboxylic acid ion exchange resin to separate the alkylene oxide from the aqueous mixture. The ion exchange capacity of the resin is regenerated with an acid wash at a temperature of at least 60° C., wherein regeneration of the resin does not result in the formation of dioxane in the spent acid wash. The process is particularly useful in purifying an aqueous 3-hydroxypropionaldehyde solution derived from an aqueous extraction of a hydroformylation reaction mixture containing ethylene oxide.

Abstract: A process for preparing 1,3-propanediol comprising the steps of: (a) preparing an aqueous mixture of 3-hydroxypropanal, (b) passing said aqueous 3-hydroxypropanal mixture to a hydrogenation zone wherein the hydrogenation zone is comprised of at least two stages wherein the hydrogenation in the first stage is carried out under hydrogenation conditions at a temperature in the range of about 50 to about 130° C. in the presence of a fixed bed or slurry hydrogenation catalyst and wherein an acidic co-catalyst is added or present in at least one of the later stages and the hydrogenation in said later stages is carried out under hydrogenation conditions at a higher temperature than that of the first hydrogenation stage and in the range of about 70 to about 155° C. to form an aqueous solution of 1,3-propanediol; and (c) recovering said 1,3-propanediol.

Abstract: The present invention is an improvement upon the process for the production of 1,3-propanediol wherein an aqueous solution of 3-hydroxy propanal is formed, catalyst, if any, used in said formation is removed from the solution, sodium hydroxide is added to the solution to neutralize any acid therein such that the pH is at least about 5, the neutralized aqueous solution is subjected to hydrogenation to produce a crude 1,3-propanediol mixture which is distilled to produce 1,3-propanediol, water, and reactive heavy components. The improvement on this process comprises replacing the sodium hydroxide with a hydroxide selected from the group consisting of ammonium hydroxide, alkali metal hydroxides other than sodium hydroxide, and alkaline earth metal hydroxides to reduce the viscosity of the reactive heavy components.