丙烯环氧化合成环氧丙烷新技术的研究进展

评述了以分子氧和双氧水为氧源的丙烯环氧化催化剂体系的最新研究进展。其中包括金属Ag催化剂。金属熔盐混合物，钛硅沸石TS-1和过渡金属络合物催化剂体系，根据氧转移机理。金属Ag催化剂和熔盐体系是以分子氧为直接氧源，而TS-1和最近报道的反应相转移含钨催化剂本质上是以过氧化氢为直接氧源。TS-1和反应相转移含钨催化剂和优点是反应条件较温和，生成环氧丙烷的选择性和产率较高。如一种负载成“蛋壳醇作为溶剂），环氧丙烷选择性和产率（以双氧水计）分别可达92%和90%以上。催化剂运转1000h以上性能稳定，今后的一个重要发展方向是开发以分子氧为起始氧源，简单高效的原位双氧水工艺。

Research Progress on New Technology of the Epoxidation of Propylene

Recent research progress on the propylene epoxidation catalysts which use molecular oxygen or hydrogen peroxide as oxidants is reviewed.Four catalytic systems,i.e.,silver catalysts,molten salts,titanium silicalite (TS-1) and transition metal complexes are discussed in detail.According to the transferring path of active atomic oxygen during the epoxidation,both silver catalysts and molten salts directly utilize molecular oxygen as oxidants,but they still suffer from low selectivity and yield of propylene oxide.While TS-1 and the most recently emerging reaction-controlled phase-transfer tungsten-containing catalyst need hydrogen peroxide as direct oxidant,they can be operated under relatively milder reaction conditions and give quite higher selectivity and yield of propylene oxide.For example,a kind of TS-1 catalyst,when co-fed by dilute hydrogen peroxide and propylene,can keep a more than 92% selectivity and a 90% yield of propylene oxide during 1000 hours' continuous operation.Owing to the cost and transportation problem,however,the use of hydrogen peroxide as oxidant has obvious drawbacks.Therefore,efforts to produce hydrogen peroxide in situ using molecular oxygen as starting feed are very important.