Dehydrogenation – Heterogeneous

Abstract

The dehydrogenation of alkanes is an important industrial reaction, widely used to produce olefins. This endothermic reaction is thermodynamically favored at high temperatures and low pressures. As a result, it typically operates under severely deactivating conditions. Therefore, the design of effective catalysts and processes is an interesting technical challenge. Catalytic dehydrogenation is employed in the production of propylene, isobutylene, C 6 –C 19 monoolefins, as well as styrene from ethylbenzene. Dehydrogenation is typically carried out on noble metal catalysts, such as Pt, or oxide catalysts, such as chromia. Promoters are used to improve the selectivity and stability of dehydrogenation catalysts. On Pt‐based catalyst, the preferred promoter is Sn, which modifies Pt geometrically and electronically to reduce the undesired side reactions, hydrogenolysis, and coking. On chromia‐based catalysts, the addition of alkali improves the performance. In addition to Pt‐ and chromia‐based catalysts, other catalytic materials have been used in dehydrogenation reactions. They include iron oxide, zinc titanates, and sulfided nickel.