Work

Mars in situ oxygen and propellant production by non-equilibrium plasmas

Year: 2021

Type: article

Abstract: It has been recently advocated that Mars has excellent conditions for oxygen and fuel production directly from atmospheric CO 2 using non-equilibrium plasmas. The Martian conditions would be favorable for vibrational excitation and/or enhanced dissociation by electron impact, two important pathways for CO 2 plasma dissociation. Herein we confirm these theoretical predictions by measuring, for the first time, the vibrational temperatures of CO 2 and the CO and CO 2 concentrations in realistic Martian conditions. In situ Fourier transform infrared spectroscopy measurements are performed in experiments conducted in DC glow discharges operating at pressures p = 1–5 Torr, discharge currents I = 10–50 mA, initial gas temperatures of 220 K and 300 K, both in pure CO 2 and in the synthetic Martian atmosphere 96% CO 2 –2% Ar–2% N 2 . To analyze and interpret the experimental results, we develop a detailed self-consistent kinetic model for pure CO 2 plasmas, describing the coupled electron and heavy-particle kinetics. The simulation results are in very good agreement with the experimental data. It is shown that the low-temperature conditions may enhance the degree of vibrational non-equilibrium and that the Martian atmospheric composition has a positive effect on CO 2 decomposition. Accordingly, the present investigation confirms the potential of plasma technologies for in situ resource utilization on Mars.

Source: Plasma Sources Science and Technology

DOI: 10.1088/1361-6595/abec28