Abstract: With growing demand for propylene and increasing production of propane from shale gas, the technologies of propylene production, including direct dehydrogenation and oxidative dehydrogenation of propane, have drawn great attention in recent years. In particular, direct dehydrogenation of propane to propylene is regarded as one of the most promising methods of propylene production because it is an on-purpose technique that exclusively yields propylene instead of a mixture of products. In this critical review, we provide the current investigations on the heterogeneous catalysts (such as Pt, CrO_x, VO_x, GaO_x-based catalysts, and nanocarbons) used in the direct dehydrogenation of propane to propylene. A detailed comparison and discussion of the active sites, catalytic mechanisms, influencing factors (such as the structures, dispersions, and reducibilities of the catalysts and promoters), and supports for different types of catalysts is presented. Furthermore, rational designs and preparation of high-performance catalysts for propane dehydrogenation are proposed and discussed.

Key words: Propane dehydrogenation, Propylene, Heterogeneous catalyst, Active site, Catalytic mechanism