Dual Functional Reactor for Direct Air Capture of Carbon Dioxide and Production of Oxygenated Hydrocarbons in One Pot

There are a few major challenges associated with direct air capture (DAC) of carbon dioxide, including 1) lowering capture costs and 2) disposal or usage of the captured carbon dioxide. On the other hand, converting carbon dioxide with renewable electricity into useful products and/or fuels has been hindered by the problems of 1) high costs and 2) availability of carbon dioxide. A new technology - Adsorption Concentrated Electrochemical Reactor (ACER) process is proposed to integrate direct air capture with subsequent conversion to C2+ oxygenated hydrocarbons into unit operation system, using renewable electricity. The ACER process simplifies process steps, eliminates usage of expensive equipment, and achieves energetic synergism between the capture and conversion steps. The ACER reactor unit operates at low temperature and low pressures and uses carbon dioxide and water in the air as feedstock. No other chemicals or feedstock is needed. Thus, the ACER unit can be deployed and operated wherever renewable electricity is available. The feasibility of the ACER process and associated electrochemical (EC) reactor concept has been demonstrated by laboratory-scale tests. A gas/liquid two-phase EC reactor design has been invented and tested using proprietary cathode catalyst prepared by Argonne National Laboratory (ANL) and proprietary andic membrane electrode assembly (MEA) prepared by Molecule Works Inc. (MWI). MWIĺs adsorption-based DAC prototype apparatus is used to produce CO2 gas on site for the EC cell tests. CO2 gas produced from the DAC can be directly converted to C2+ oxygenates via. the EC reactor without any additional purification. Preliminary design and economics analysis indicates that with the electrical efficiency and reactor productivity achieved by this team, C2+ products can be produced from air at cost competitive with ethanol market price. In phase II, the EC cell designs will be further optimized to enhance the C2+ product selectivity and electrical efficiency. Longer-time stability of the EC cell operation will be demonstrated. The EC stack and system prototype with about 1kg/day of product capacity will be developed and demonstrated to show scaleup feasibility of the optimum catalyst and MEA materials, and fabrication of this new type of EC reactor. Process parametric tests will be conducted on the prototype unit to produce performance data for commercial-scale process designs and produce large amounts of products for accurate C atomic balance and for customer tests. The C2+ products including ethanol, acetic acid, isopropanol, and acetone can be easily stored and transported. They can be used as oxygenated fuels, upgraded to jet fuels, or separated into individual chemicals. The market for these products is large. Compared to fossil fuels, net reduction to carbon dioxide emissions can be 99%.