中文摘要：

环氧丙烷（PO）是仅次于聚丙烯和丙烯腈的第三大丙烯衍生物,广泛应用于轻工、医药和纺织等行业。相比于传统的氯醇法和共氧化法,在临氢条件下使用氧气直接氧化丙烯生产PO的工艺具有绿色环保、操作简单、经济性高等优势,是当前国内外PO生产领域的研究热点。本文针对该领域仍存在的催化剂寿命短、活性低等亟待解决的问题,综述了国内外近年来的研究进展,着重介绍催化剂中含钛载体的表面和结构性质、金属颗粒的形貌和电子效应对丙烯直接气相环氧化反应活性、稳定性的影响机制,并评述了催化剂的反应机理及结焦失活机理。此外,还总结了Cs、Ag、Pd、Pt、Ge、表面烷基化、离子液体、氮掺杂等助剂对催化性能的影响,分析了丙烯环氧化反应过程尚存的难题。最后,从载体材料的选择、催化剂性能的改进等方面展望了可能的解决途径和方向。

英文摘要：

Propylene oxide（ PO）,as the third largest propene derivative ranking behind polypropylene and acrylonitrile,is widely used in light industry,pharmaceutical and textile industries. Compared with traditional chlorohydrin and hydroperoxide processes,direct propene epoxidation with hydrogen and oxygen to synthesize PO has the advantages of being green,simple and profitable. It is therefore a current worldwide research hotspot. Herein,recent progress is reviewed with the purpose of solving remaining problems such as poor stability and low activity. M oreover,the effect of surface and structural properties of Ti-containing supports together with the morphologic and electronic effect of gold nanoparticles on catalytic activity and stability areintroduced. The reaction mechanism and deactivation mechanism are further discussed. The influences of additives such as Cs,Ag,Pd,Pt,Ge,surface alkylation,ionic liquid and nitrogen doping on catalytic performance are summarized. The existing problems in direct propene epoxidation with H2 and O2are also analyzed. In the end,possible solutions and directions from the aspects of selecting supports and improving catalytic performance are remarked.