Electrochemistry to fuels and chemicals

Publieke samenvatting / Public summary

Through catalysis liquid lignocellulosic feedstocks (bioliquids) can be transformed into highly valued (usually oxygenated) chemicals or oxygen-free fuels ('biofuels'). An essential step in the conversion is the selective functionalization of the oxygen containing molecules. The required hydrogenation reactions are currently deployed in reactors operated at elevated temperatures, applying hydrogen at high pressures (up to 200 bar) in the presence of heterogeneous catalysts. Unfortunately, these catalysts suffer from deactivation, limiting practical application.

EC2Fuel will investigate the feasibility of sustainable, electrocatalytic conversion of liquid biomass derived products ('bioliquids') into fuel intermediates / precursors. Reactions include the previously mentioned anodic decarboxylation of acids and C-C-bond formation with concomitant evolution of CO2 (electrochemical Kolbe reaction), and cathodic hydrogenating / deoxygenation of ketones to hydrocarbons.

Korte omschrijving
Another possibility to stabilize and convert biomass related pyrolysis liquids is by electrochemical techniques. For example, anodic conversion (selective oxidation) of acids has been demonstrated to form gas (for example CO2 and ethane in case of acetic acid). The protons and electrons generated at the anode, can be applied to reduce the also unwanted aldehydes/ketones into alcohols at the cathode, or alternatively to form hydrogen. This provides a simple, cheap and very effective method to not only upgrade the bio-liquids, but also to produce hydrogen for further processing if required. This approach is proposed here in 'EC2Fuel'.

Research activities focus on catalyst development (both for anode and cathode), and integration thereof in redox flow cells by constructing a catalyst-electrode-assemblies (CEA). Mild operating conditions and modest scales are to be deployed, while allowing a flexible and easy integration with renewable electricity.