Combined process for the manufacture of ethylene oxide and ethanolamines, by catalytic oxidation of ethylene and subsequent reaction of part of the ethylene oxide produced with ammonia

摘要

The invention firstly produces a mixture of water enriched with ethylene oxide, of which part is sampled and contacted with ammonia to produce ethanolamines ; the remaining part is processed to obtain pure ethylene oxide. The combined preparation of ethylene oxide and ethanolamine(s) comprises the following stages (1) (a) synthesis of ethylene oxide by contact of ethylene with molecular oxygen in the presence of a catalyst to form a gaseous mixture containing ethylene oxide; (2) (b) an absorption stage by contact of the gaseous mixture with water to form a dilute solution of ethylene oxide; (3) (c) a desorption stage of the dilute solution by entrainment with water vapour to form an ethylene oxide-enriched mixture and separation from the mixture of an ethylene oxide-depleted solution which can be returned to stage(b); (4) and(c) purification of the ethylene oxide by distillation of the enriched aqueous solution and separation of pure ethylene oxide. Part of the mixture of water enriched with ethylene oxide is sampled before stage(d) then contacted directly or indirectly with ammonia(stage e of synthesis of ethanolamine(s).