(509ax) Ethane Dehydrogenation over Co/SiO2 and Its High-Temperature Treatment Effect

Light olefins such as ethylene and propylene are important building blocks for modern chemical industries. With the increasing demand over the past decades and recent shale gas revolution, direct dehydrogenation of alkanes to olefins has become an economically viable choice to produce light olefins¹. Co/SiO₂ is a highly active and selective catalyst for light olefin dehydrogenation, which is also low-cost and environmentally friendly^2–4. However, the active site structure and reaction mechanism remain unclear and catalyst activity requires further improvement.

In this study, we synthesized Co/SiO₂ with a facile electrostatic adsorption method and optimized the catalyst activity with regard to cobalt loadings and pretreatment conditions. A facile high temperature pretreatment method was found to increase the initial activity of the catalyst up to 4 times. Extensive spectroscopic characterizations such as FTIR, XAS, and XPS were conducted to investigate the structure-function correlations of Co/SiO₂. In addition, micro kinetic modeling of the proposed site in combination with kinetics experiments reveals the active site structure. Post characterization indicates that hydrogen generated by the reaction plays a key role in catalyst deactivation.