Separation and recovery of 3-methyl-3-butene-1-ol
AssigneeKuraray Co., Ltd.
InventorsSunao Kyo, Hideaki Oka, Katsuhiko Hayashi, Hidetsugu Tanaka
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Abstract
The 3-methyl-3-butene-1-ol contained in the oily mixture obtained in the production of isoprene by the reaction of isobutene and formaldehyde through the intermediate 4,4-dimethyl-1,3-dioxane can be isolated by adding boric acid to said mixture to form the boric acid ester of 3-methyl-3-butene-1-ol and recovering the higher boiling fraction having a boiling point of above 160.degree.C.
Claims6
A process for the separation and the recovery of 3-methyl-3-butene-1-ol from an oily mixture containing the same and 4,4-dimethyl-1,3-dioxane, which mixture is obtained during the production of isoprene by the reaction of isobutene and formaldehyde through the intermediate 4,4-dimethyl-1,3-dioxane, said oily mixture having a boiling point not lower than 85.degree.C at atmospheric pressure, which process comprises the steps of (1) heating at a temperature ranging between about 92.degree. to 160.degree.C said oily mixture in the presence of one-third to one-half mole of boric acid or boric acid anhydride per mole of 3-methyl-3-butene-1-ol contained in said oily mixture while eliminating the generated water azeotropically with 4,4-dimethyl-1,3-dioxane, (2) removing therefrom a first fraction by distillation which boils at a temperature not higher than 160.degree.C at atmospheric pressure to separate the fraction containing 4,4-dimethyl-1,3-dioxane from a second fraction containing boric acid ester of 3-methyl-3-butene-1-ol, (3) recovering the second fraction remaining and (4) isolating 3-methyl-3-butene-1-ol therefrom.
Dependencies are inferred from the claim text.