Propylene of C. P. Grade dissolved in t-butanol was catalytically oxidized to propylene epoxide using cumene hydroperoxide, which was prepared by contacting cumene with oxygen. The catalysts used were molybdenum, manganese, cobalt, and copper compounds.
The work of searching the optimal reaction conditions, reaction mechanisms, and its kinetics were attempted by conducting several series of experiments.
It was confirmed in this work that, among catalysts used, the molybdenum catalyst was the only effective one for the selective formation of propylene oxide, and the effective concentration of the catalyst was limited to only a small value ; the higher the concentration of molybdenum in reacting solution, the less the portion of cumene hydroperoxide was used for converting propylene into propylene oxide, or the lower the selectivity for forming propylene oxide.
The selectivity attained in this work was more than 98 % at reaction temperatures ranging from 80 ℃ to 105 ℃ when the initial relative concentrations of cumene hydroperoxide, t-butanol, and propylene in liquid phase were 1, 4, and 16 moles per liter and the molybdenyl naphthanate, less than 1.3×10^-3 mole per mole of cumene hydroperoxide, was mixed into reactants.
The rate of formation of propylene oxide is
dx/dt = K[ROOH][CH₃CH=CH₂][Mo]^α （1≤α≤2）
The rate increased about twice by the raise of 10 ℃ in reaction temperature.
The activation energy calculated from the Arrhenius plot is 18.8 Kcal/mole.