Patent ID: 6582565
Filing Date: 2003-06-24
Classification: B01D,C07D,Y02P

Abstract:
Process for the separation of 3,4-epoxy-1-butene (epoxybutene) from a mixture comprising epoxybutene and at least one aliphatic or aromatic hydrocarbon containing five to seven carbon atoms and having a boiling point of between about 20 and 115Â° C. which comprises the steps of:(1) feeding a mixture comprising epoxybutene and at least one hydrocarbon selected from aliphatic or aromatic hydrocarbons containing five to seven carbon atoms and having boiling points of between about 20 and 115Â° C., to the mid-section of an extractive distillation column; (2) feeding an extractive distillation solvent to the upper section of the extractive distillation column; (3) removing from the upper section or top of the extractive distillation column a vapor comprising the hydrocarbon; (4) removing from the lower section or base of the extractive distillation column a liquid comprising epoxybutene and extractive distillation solvent; and (5) separating the liquid of step (4) into epoxybutene and extractive distillation solvent; wherein the extractive distillation solvent (i) is inert, (ii) does not form an azeotrope with either epoxybutene or the hydrocarbon, (iii) is miscible with epoxybutene and the hydrocarbon, (iv) has a boiling point at least about 20Â° C. higher than the higher boiling point of epoxybutene and the hydrocarbon, and (v) creates a large relative volatility difference between epoxybutene and the hydrocarbon; and wherein the extractive distillation solvent is selected from the group consisting of C3 to C12 alcohols, C5 to C12 aliphatic ketones; alkyl alkanoate esters containing a total of 6 to 12 carbon atoms, C6 to C12 aliphatic and cyclic ethers, glycol ethers containing a total of 4 to 12 carbon atoms, glycol ether esters containing a total of 5 to 12 carbon atoms, polar aprotic solvents, and mixtures thereof.