Study And Application Of Reaction-controlled Phase Catalysis Transfer On The Epoxidation

Epoxide compound is one of the most important fine chemical intermediates. Currentindustrial production method of epoxide gives rise to serious problems of equipmentcorrosion and environmental pollution. The new production method in consistent with thegreen chemistry and cleaner is required. Thus, environmental friendly catalytic methods forepoxidation with clean oxidant are actively investigated. In this thesis, a kind ofreaction-controlled phase-transfer catalyst was synthesized and used in the epoxidation ofstyrene and HTPB with a good activity and selectivity. This catalytic system possesses theadvantages of both homogeneous and heterogeneous catalysts, and the catalyst precipitatedafter oxidation reaction for easy recycling.Firstly, The system of (n-C₁₆H₃₃N（CH₃）₃)₃[PW₄O₁₆]/H₂O₂was used in epoxidation ofstyrene. The factors such as the solvents, the amount of H₂O₂, the amount of catalyst, reactiontemperature, reaction time, and the concentration of substrate were investigated. It is foundthat the optimized conditions are ethyl acetate as a solvent, n（H₂O₂）:n（double bond ofSubstrate）=1:1, n（double bond of Substrate）:n（catalyst）=300:1, the concentration ofsubstrate=10%,60℃,6h. Up to72.6%of the yield was obtained under the optimizedconditions and the catalysis can be reused and keep good stability. By adding a little theadditive and inhibitor to the reaction system, the effect of epoxidation was improved.Then the system of (n-C₁₆H₃₃N（CH₃）₃)₃[PW₄O₁₆]/H₂O₂was used in epoxidation ofHTPB. The factors such as the solvents, the amount of H₂O₂, the amount of cat alyst, reactiontemperature, reaction time, and the concentration of substrate were investigated. It is foundthat the optimized conditions are1,2-dichloroethane as a solvent, n（H₂O₂）:n（double bond ofSubstrate）=1:1, n（double bond of Substrate）:n（catalyst）=100:1, the concentration ofsubstrate（based on solvent）=65g/L,60℃,6h. Up to8.74of the epoxy value was obtainedunder the optimized conditions and the catalysis can be reused and keep good stability.