Prospects of Electrifying Chemical Manufacturing through Co-Conversion

Over the next few decades the chemical industry will need to reduce drastically the greenhouse gas emissions footprint associated with the manufacturing of chemicals and fuels. Electrifying manufacturing of some intermediates or products holds promise to help meet this challenge. While techno-economic (TEA) and life-cycle (LCA) analyses of the electrochemical reduction of CO2 to products such as CO, formic acid, ethylene, and ethanol indicate their promise, these also highlight the challenge to compete in terms of cost with present day chemical conversion processes operated at scale [1]. This contribution will elaborate on the prospects of electrochemical co-conversion: performing desired chemical conversions on both electrodes of an electrolyzer. Such an electrolysis process not only uses renewable energy to produce two or more value added products simultaneously, it also avoids the energy intense oxygen evolution reaction that oftentimes is paired with CO2 reduction or hydrogen evolution (water electrolysis). Indeed, when coupled with CO2 reduction to CO, the oxygen evolution reaction on the anode consumes about 90% of the energy required to drive the overall process. Performing oxidation reactions, in particular oxidation of organic substrates, reduces the cell potential by about 0.8V, representing a reduction in overall energy consumption of 30-50%, depending on the cathode process and operating conditions. . Co-conversion electrolysis process technology could be a starting point for a new generation of chemical manufacturing technology that is significantly more energy efficient than the traditional thermochemical processes, while also able to use renewable feedstocks, such as CO2, water, biomass adducts, or organic waste streams. This presentation will dive into technoeconomic and lifecycle analyses of a wide range of co-conversion scenarios. Using gross margin and other models, the question will be answered which electrolysis process comprised of specific combinations of cathodic reactions (CO2 reduction, hydrogen evolution, ...) and anodic reactions (various specific oxidations of organic compounds) will have the best economic prospects. Similarly, the work will provide insights as to what combinations of anodic and cathode chemical conversions are most promising from a lifecycle point of view, in reducing CO2 emissions. This work also will provide insights with respect to what factors (catalyst cost, electrode durability, ...) have the most potential in helping to further improve economic viability and to further reduce CO2 emissions.