Patent ID: 6833057
Filing Date: 2004-12-21
Classification: C07D,Y10S

Abstract:
A process for purification of ethylene oxide by distillation, comprising the step in whichan aqueous mixture comprising ethylene oxide, formaldehyde and at least 5% by weight of water is introduced via a feed into a distillation apparatus comprising at least one packed column which contains a structured or bulk packing and has a specific mass transfer area A, the mixture being introduced at a height above the bottom of at least xmin, in m, which for a given specific mass transfer area A, in m2/m3, is given by the equation xmin=5.5 mâˆ’AÂ·0.006 m2, pure ethylene oxide containing 4 ppm or less formaldehyde, is taken off at the top and in the bottom phase a mixture is obtained which contains less than 5% by weight of ethylene oxide; an acetaldehyde enriched fraction is removed as a sidestream from the column at a side take-off located between the too and bottom of the column, and wherein the aqueous mixture is introduced via the feed at a height of from 1.5 xmin to 7 xmin.