2016 AIChE Annual Meeting
(461f) CO2 Hydrogenation on Silica- and Titania- Supported Single-Site Heterogeneous CoII Catalyst
Authors
In this presentation, single-site CoII catalyst for the CO2 hydrogenation will be discussed. Single-site Co supported on silica are synthesized using methods adapted from literature[5]. Since the active site for this reaction is the highly stable CoII center, titania was also explored as a support due to its strong metal-support interaction with Co in the oxidized state[4], leading to enhanced activity compared to silica supported Co catalyst. The stability of the CoII active site comes from its tetrahedral geometry with neighboring oxygens from the oxide supports. Understanding the interactions with isolated metal ions with a uniform active site can provide insight into the mechanism of CO2 hydrogenation, which is still widely debated. In order to obtain a detailed understanding of the catalytic activity of the single-site CoII we must verify the surface species are in an isolated geometry. To this end the techniques that will be used to characterize the surface are Raman spectroscopy, diffuse reflectance UV-vis, TPR, and STEM-HAADF. These characterization techniques coupled with reaction data can correlate the activity of single-site heterogeneous CoII catalyst for CO2 hydrogenation.
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