Creating chemical building blocks via electrochemistry is abundantly researched to provide a sustainable production process. Especially the electrochemical reduction of carbon dioxide is of interest. Usually, it is paired with the oxygen evolution reaction (OER). However, oxygen is unattractive from a financial perspective [1]. Therefore, an alternative oxidation reaction producing high-value products is desired to pair with CO₂ reduction.

In this research we focus on the epoxidation of alkenes, such as ethylene and propylene, as oxidation reaction. For the epoxidation reaction, we will be using a redox mediated system based on silver pyridine systems that was developed in the late 80’s [2]. A major challenge within this system is the low solubility of these gaseous alkenes. A way to overcome this low solubility is to introduce the gas locally at the electrode surface, which can be realized with a hollow fiber electrode. This is an electrode configuration that has a porous electrode wall and therefore, a gas can be introduced directly at the electrode surface. We will discuss the results obtained by applying the silver pyridine based redox mediated system to the hollow fiber electrode and discuss future steps for the realization of the paired electrolysis of CO₂ reduction with alkene epoxidation.

[1] Á. Vass, B. Endrodi and C. Janáky, Current Opinion in Electrochemistry 2021, 25:100621

[2] J.M. van der Eijk et al., Catalysis Today, 259-266 (1988)

Tessa de Koning Gans started her PhD at the Photocatalysis Synthesis group at the University of Twente in 2022. Her research focusses on the epoxidation of alkenes as an alternative anodic reaction in electrochemical CO2 reduction. Within her research she uses a special electrode configuration, the hollow fiber electrode. Her project is part of the Advanced Research Center for Chemical Building Blocks consortium (ARC CBBC) and is part of the multilateral project new chemistry for the future.