Plasma-based CO₂ Conversion for Mars ISRU

Plasma-based CO₂ conversion is a promising power-to-gas chemical synthesis process for Mars In-Situ Resource Utilization (ISRU). The abundant CO₂ in the Martian atmosphere can be converted into breathable oxygen and fuel for astronauts, enabling safer and more independent Mars missions while reducing launch costs. Nonthermal plasma technologies leverage electron excitation chemistry to achieve kinetic activation and split the stable bonds of CO₂ at modest temperatures and pressures compared to typical thermal conversion processes. Other benefits of Plasma-based conversion technologies include the compatibility with many feedstock gases, opening up possibilities for synthesizing other important chemicals in situ. Many plasma sources have been explored for CO₂ conversion, and an understanding of the fundamental atomic processes in CO₂ plasmas has led to validated chemical kinetic mechanisms. However, there have been limited parametric studies that directly compare the chemical performance of reactors under varied operating conditions. Understanding the coupled pressure, temperature, and reduced electric-field dependence of the relevant chemical processes’ will inform the system-level reactor design, including the pumps, heaters, and electronics required. This thesis describes a parametric exploration of a nanosecond repetitively pulsed plasma reactor under different operating conditions to compare reactor performance and elucidate the important kinetic effects. A 0-D chemical kinetic model is developed and described in detail, building upon previous work to ensure the mechanism is appropriate for the defined conditions. A tradespace is constructed in terms of important performance metrics such as conversion, efficiency, and specific energy input. To understand the primary kinetic pathways, a first-order sensitivity analysis is conducted on selected conditions. This work contributes a robust analysis of NRPD reactor performance to extend fundamental plasma studies for the engineering of a competitive technological candidate for Martian ISRU.

Name thesis:degree_name

Master

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Aeronautics and Astronautics

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2024

Author dc:creator

• McKinney, Lanie G.

Advisor dc:contributor.advisor

• Guerra-Garcia, Carmen

Statement dc:rights

• In Copyright - Educational Use Permitted
• Copyright retained by author(s)

Licence dc:rights.uri

• https://rightsstatements.org/page/InC-EDU/1.0/

Handle dc:identifier.uri

https://hdl.handle.net/1721.1/155377

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/155377