Tobias Duyster

 

Investigation of the future potential of high temperature CO2-electrolysis

Electrochemical impedance spectra (EIS) at 80%CO2-20%CO depending on the current density Copyright: L. Dittrich Electrochemical impedance spectra (EIS) at 80%CO2-20%CO depending on the current density

Conventional processes in the chemical industry are often dependent on fossil fuels, finite raw materials and emit climate-damaging greenhouse gases. A sustainable approach is the so-called CO2 electrolysis.

Converting electrical energy from renewable energies such as wind energy into chemical energy makes it to a direct method to pursue sustainable value creation. To this effect, the greenhouse gas CO2 is reduced to CO in a solid oxide electrolysis cell. The obtained CO is an important raw material for the chemical industry, since it can be used to obtain hydrocarbons, which allows the production of biofuels or plastics.

The high temperatures between 700°C-900°C required for this technology, thermodynamically favor the electrolysis process and increase the efficiency of the cell.

In this thesis the performance of the electrolysis cell is examined depending on the reaction parameters gas composition, temperature and volume flow by using of impedance spectroscopy and current/potential-curves.

Based on the results the kinetic processes of CO2 electrolysis with various parameter settings can be optimized and the potential of the technology increased.