Simultaneous High Conversion and Selectivity in Olefin Oxidation with Oxygen Through Solid/Liquid/Gas Three-Phase Interface Design

摘要

In oxidation reactions with oxygen as oxidant, low O-2 concentration on catalyst surface under ambient pressure is a major kinetic limitation for selective oxidation of olefins; while increasing O-2 pressure to enhance the reaction rate suffers lower selectivity due to thermodynamic factors. In this study, we demonstrate that simultaneous enhancement of conversion and selectivity can be achieved under ambient pressure by solid/liquid/gas three-phase interface design. We produced Au nanoparticles supported on graphene aerogel with superaerophilic surface (denoted as Au/GA) as the catalyst for demonstration. The results show that O-2 gas shows "bursting" behavior on the surface of Au/GA under water, resulting in rapid adsorbing of O-2 in 98 ms and therefore high O-2 concentration on the surface of catalyst. Thus, solid/liquid/gas three-phase interface is formed under this condition, leading to high conversion as well as high selectivity at ambient O-2 pressure. Such strategy is expected to find wide applications in many other selective oxidation reactions that traditionally needed high pressure.