(478a) Understanding and Characterizing a Novel Cell Design for the Electrooxidation of Cyclohexene Towards Value Added Chemicals

Due to increased reaction tunability and the rising production of renewable energy, electrochemically catalyzed processes have the potential to replace thermally catalyzed processes for the sustainable production of a variety of industrially relevant chemicals. However, electrocatalysis is still a relatively new and unexplored field, especially towards the production of more complex chemical species. The practical use of sustainable electrochemical processes over the coming years will therefore depend on rapidly developing a fundamental understanding of the unique reaction networks and mass transport processes present in these systems.

In this work, we investigate the direct electrooxidation of cyclohexene in a biphasic electrochemical cell using water as an oxidant. Our novel cell design (Figure 1) allows for the reaction of two otherwise immiscible liquids at a porous electrode interface, which both supports the formation of a three phase boundary region and allows for in situ product separation. Several metal oxides are employed as catalysts to explore relationships between catalyst activity, product distribution, and relative binding strength to oxygen surface species under reaction conditions. Reaction operating conditions such as pH and applied potential are also systematically explored to understand their effect on these performance metrics. Cell activity is assessed via cyclic voltammetry and total charge passed during chronoamperometry, while products are analyzed via Gas Chromatography – Mass Spectroscopy and Nuclear Magnetic Resonance to determine reaction selectivity in both the aqueous and organic phases. Catalysts are additionally analyzed via a variety of techniques to identify their physical and chemical structure before and after catalysis. We find that a range of cyclic hydrocarbons and oxides are formed, in competition with oxygen evolved from water splitting; activity and selectivity results are shown in Figure 1 below under three reaction conditions.