Patent ID: 7005529
Filing Date: 2006-02-28
Classification: B01D,C07D,C08G

Abstract:
1. A process for the separation of an aqueous mixture of trioxane and formaldehyde, said mixture having a first trioxane to formaldehyde ratio, said process comprising the steps of reacting the aqueous mixture of trioxane and formaldehyde, which is in vapor phase, with a urea solution; wherein said reacting step includes the steps of scrubbing said aqueous mixture of trioxane and formaldehyde with the urea solution in a scrubbing column; and separating an exiting vapor phase and an exiting liquid phase, wherein said exiting vapor phase has a second trioxane to formaldehyde ratio that is higher than said first trioxane to formaldehyde ratio and said exiting liquid phase is a urea-formaldehyde solution, and wherein, at a foot of said scrubbing column, a formaldehyde to urea molar ratio is between 1:1 and 6:1.