METHOD OF PRODUCING ALKYLENE GLYCOL Russian patent published in 2012 - IPC C07C31/20 C07C29/10 C07D303/02 C07D301/04 

FIELD: chemistry.

SUBSTANCE: present invention relates to a method of producing alkylene glycol, which can be used as a raw material in production of polyester fibres, polyethylene terephthalate plastic and resins, as well as in antifreeze liquids. The method involves the following steps: (a) reaction of alkene with oxygen in the presence of a catalyst in a reactor to obtain a gaseous composition which contains alkylene oxide, alkene, oxygen, carbon dioxide and water vapour, and removing contaminants from the gaseous composition; (b) feeding the gaseous composition from step (a) into an alkylene oxide absorber, having a column of vertically stacked plates or having a packed column, feeding the impoverished absorbent into the alkylene oxide absorber, bringing the gaseous composition into contact with the impoverished absorbent in the alkylene oxide absorber in the presence of one or more catalysts which facilitate carboxylation and hydrolysis, and removing the saturated absorbent from the alkylene oxide absorber, where the impoverished absorbent contains at least 20 wt % and less than 80 wt % water, wherein at least 50 wt % alkylene oxide coming into the alkylene oxide absorber is converted in the alkylene oxide absorber and where temperature in the alkylene oxide absorber ranges from 50 to 160°C; (c) optionally feeding a portion or all of the saturated absorbent from step (b) into one or more final treatment reactors and removing the product stream from the one or more final treatment reactors, where at least 90% of alkylene oxide and alkylene carbonate coming into one or more final treatment reactors are converted to alkylene glycol in one or more final treatment reactors; (d) optionally feeding the saturated absorbent from step (b) or the product stream from at least one or more final treatment reactors at step (c) into a flash vessel or into an apparatus for evaporating light fractions, and removing the light fractions; (e) feeding the saturated absorbent from step (b) or (d) or the product stream from step (c) or (d) into a dehydrator, removing water and obtaining a stream of dehydrated product; and (f) purifying the stream of dehydrated product from step (e) and obtaining a product stream of purified alkylene glycol.

EFFECT: method enables to reduce the cost and complexity of the apparatus while ensuring high selectivity.

12 cl, 1 ex, 6 dwg