Solar-Plasma Reactors and Processes for Sustainable Chemical Synthesis

The synthesis of fuels and chemicals utilizing renewable energy via environmentally-benign methods is recognized as essential towards achieving sustainable development. Solar-plasma chemical synthesis seeks to combine the sustainability advantages and scalability of concentrated solar thermochemical techniques and the versatility, continuous operation, and high-efficiency of plasmachemical methods. Solar-plasma processes are characterized by their ratio of input solar power (P_s) to input electric power (P_e) as either Solar-Enhanced Plasmachemical (SEP, for P_e > P_s) or Plasma-Enhanced Solar thermochemical (PES, for P_s > P_e). This talk summarizes the rationale of solar-plasma chemical synthesis reactors and processes and presents two specific implementations for the conversion of carbon dioxide (CO₂): solar-microwave plasma SEP and solar-gliding arc discharge PES. The rationale and evaluation of each approach is presented and contrasted. Particularly, solar-microwave plasma processes allow greater power densities circumventing the limitations of skin-depth power absorption, and solar-glidarc approaches present simpler operation and potential integration with solar thermochemical methods. Strategies for the advancement of solar-plasma methods for sustainable chemical synthesis are discussed.