Optimization of Electrode Material, Morphology and Geometry for Electro-Swing DAC of CO2

Direct air capture (DAC) of carbon dioxide is gaining prominence as a negative emissions technology for curtailing anthropogenic carbon dioxide (CO2) emissions. While most incumbent technologies rely on temperature and pressure changes to achieve carbon capture and release, we have developed a new technology which relies solely on electrical energy input. This is the electro-swing adsorption technique, which uses electrochemical cells that can capture CO2 upon charging and release it upon discharge. While this technology is ideal for DAC, due its binary affinity to CO2 in its charged and discharged states, different aspects of the electrochemical cells require optimization to be compatible with various implementations of DAC. This optimization addresses the large amounts of oxygen in the air and the low concentration of CO2, in addition to other contaminants present in the inlet streams of low concentration carbon capture applications. The optimization proposed herein is three- pronged and it considers the electroactive material, the morphology of the electrode and the geometry of the gas flow channels. In Phase I of this work a set of optimum solutions in the optimized dimensions for various applications of DAC using the electro-swing technology will be mapped out. A combination of a number of these solutions will be ideal for one implementation of DAC for a given application. Upon the completion of a Phase I, we plan to commence Phase II which will entail the fabrication of bench-scale and pilot-scale prototypes for a number of very different DAC applications utilizing the optimum set of solutions obtained in Phase I. This will allow the commercialization of various applications of DAC, especially at the smaller scale and closer-to-consumer type applications, which will provide significant de-risking in the development and commercialization of large-scale DAC systems where deployments using the electro-swing technology can operate at a significantly reduced cost of < $100 per tonne CO2.