Epoxidation process for manufacture of olefin oxide and alcohol

Abstract

An epoxidation reaction wherein: an olefin and an organic hydroperoxide, preferably, propylene and tertiary butyl hydroperoxide are reacted in a primary reaction zone in a liquid phase with an organic solvent, preferably tertiary butyl alcohol, in the presence of a soluble molybdenum catalyst at a ratio of propylene to tertiary butyl hydroperoxide of from about 0.9:1 to about 3:1, at a reaction temperature from about 100.degree. C. to about 140.degree. C. and a residence time sufficient to convert about 85 to 95% of the tertiary butyl hydroperoxide and form a primary epoxidation zone reaction product; fractionating, in a primary fractionation zone, the primary zone reaction product into a primary distillate fraction comprising unreacted propylene and propylene oxide and into a primary heavy liquid fraction, comprising molybdenum catalyst, unreacted tertiary butyl hydroperoxide, tertiary butyl alcohol and side reaction products; reacting, in a secondary epoxidation reaction zone, the primary heavy liquid fraction with propylene in the liquid phase, with substantially no back mixing, at a molar ratio of propylene to unreacted tertiary butyl hydroperoxide of about 5:1 to about 10:1, a reaction temperature of about 110.degree. C. to about 140.degree. C. and a residence time sufficient for conversion of substantially all the tertiary butyl hydroperoxide and production of a secondary reaction zone product; fractionating the secondary reaction zone product, in a secondary distillation zone, into a secondary distillate fraction comprising unreacted propylene, and propylene oxide, and into a secondary heavy liquid fraction comprising molybdenum catalyst, tertiary butyl alcohol, and side reaction products; recovering the secondary heavy liquid product for recovery and/or disposal of molybdenum; and fractional distillation of the first distillate fraction and the second distillate fraction for recovery of propylene, and propylene oxide product.