Thermodynamic model of Mars Oxygen ISRU Experiment (MOXIE)

Abstract

As humankind expands its footprint in the solar system, it is increasingly important to make use of the resources already in our solar system to make these missions economically feasible and sustainable. In-Situ Resource Utilization (ISRU), the science of using resources at a destination to support exploration missions, unlocks potential destinations by significantly reducing the amount of resources that need to be launched from Earth. Carbon dioxide is an example of an in-situ resource that comprises 96% of the Martian atmosphere and can be used as a source of oxygen for propellant and life support systems. The Mars Oxygen ISRU Experiment (MOXIE) is a payload being developed for NASA's upcoming Mars 2020 rover. MOXIE will produce oxygen from the Martian atmosphere using solid oxide electrolysis (SOXE). MOXIE is on the order of magnitude of a 1% scale model of an oxygen processing plant that might enable a human expedition to Mars in the 2030's through the production of the oxygen needed for the propellant of a Mars ascent vehicle. MOXIE is essentially an energy conversion system that draws energy from the Mars 2020 rover's radioisotope thermoelectric generator and ultimately converts it to stored energy in oxygen and carbon monoxide molecules. A thermodynamic model of this novel system is used to understand this process in order to derive operating parameters for the experiment. This paper specifically describes the model of the SOXE component. Assumptions and idealizations are addressed, including 1D and 2D simplifications. Operating points are discussed as well as impacts of flow rates and production.

Carbon deposition and sulfur poisoning during CO2 electrolysis in nickel-based solid oxide cell electrodes

“…The products can potentially find use in the chemical industry, military operations where silent production of high purity O2 is required, or in more unconventional applications such as utilization of the CO2-rich atmosphere found on Mars [11]. In fact, an SOEC is planned to be brought on the coming 2020-NASA rover-mission for preliminary investigations [12,13]. The initial purpose is oxygen production on location to minimize the amount brought from Earth for a return tripin fuel combustion, oxygen makes up a large majority of the mass.…”

Fuel and oxygen harvesting from Martian regolithic brine

“…The metrics of the SMRB electrolyzer reported here was compared to existing plans for the generation of O 2 on Mars. MOXIE, developed by the Massachusetts Institute of Technology (MIT) and NASA as a test bed on the Mars 2020 mission, has been designed to produce 10-22 g•h −1 of O 2 by the electrolysis of CO 2 (31). Utilizing the abundant CO 2 present in the Martian atmosphere, MOXIE produces O 2 and CO, with pure O 2 obtained by subsequent purification.…”

Towards a Biomanufactory on Mars

“…While short-term forays rely on such abiotic production primarily for basic astronaut consumables like O 2 113 and fuel, longerterm missions necessitate placing a higher priority on the efficiency and scalability of ISRU systems along with a significantly expanded product spectrum. This prompts a biomanufactory able to produce and utilize feedstocks along three axes as depicted in Figure 5: CO 2 -fixation to supply a carbon and energy source for downstream heterotrophic organisms or to generate commodity chemicals directly, N 2 -fixation to provide ammonium for plants and other organisms, and regolith decontamination and enrichment for soil-based agriculture and trace nutrient provision.…”