In-situ Resource Utilization Research Articles

Polymeric Reactors for Catalytic Reactions beyond Earth

AbstractCurrent space missions to Luna and Mars are considering to use the resources, which can be found on‐site at the destination. This strategy named in‐situ resource utilization (ISRU) saves valuable pay‐load capacities during the rocket launch from the earth surface. Specifically, in mars missions it is intended to produce the necessary rocket fuel CH4 for the back‐transit to earth via water electrolysis and subsequent CO2 methanation. The present study elaborates this concept and examines the question if polymeric reactors are feasible for heterogeneously catalyzed reactions in applications beyond earth. The study aims at providing a theoretical backbone for a proof‐of‐concept. The evaluation is conducted theoretically by design considerations and adds experimental results to show the general feasibility of polymeric reactors for applicable reaction conditions.

Monte Carlo analysis of dosimetric issues in space exploration

The Radiation protection is of paramount importance in the planning of human exploration activities in space. The related risks must be considered with respect to two aspects: devising a proper shielding and providing answers to the requirement of an effective dosimetry evaluation in astronaut's activities. Both aspects have been considered using the Monte Carlo (MC) code MCNP 6.2 as the reference tool. As case study an application devised for the National Aeronautics and Space Administration (NASA) Artemis program has been chosen. The project aims to establish a sustainable human presence on the Moon, envisioning the realization of an outpost that will serve as a steppingstone for space exploration endeavors. A Class III shelter, in situ resource utilization (ISRU) built habitat for the Moon, has been designed through computational methods and topology optimization techniques, and analyzed in terms of radiation shielding performances and the strictly related structural behavior. The outpost must be able to withstand temperature variations, micrometeorite impacts, and the absence of a substantial atmosphere. Any solution studied to respect the constraints must devise robust and innovative materials and techniques to create habitats that have as goal the shielding from the Galactic Cosmic Rays (GCR) and from the solar flares to provide a safe and habitable environment at the time scales scheduled for the missions. Moreover, the outpost design must incorporate strategies for extracting and utilizing local resources. Overcoming such challenges will pave the way for the establishment of a sustainable human presence on the Moon and serve as a crucial leap for future space exploration missions.

Thermochemical interactions between yttria‐stabilized zirconia and molten lunar regolith simulants

AbstractOxygen produced through in‐situ resource utilization (ISRU) is critical to maintaining a permanent human presence on the lunar surface. Molten regolith electrolysis and carbothermal reduction are two promising ISRU techniques for generating oxygen directly from lunar regolith, which is primarily a mixture of oxide minerals; however, both processes require operating temperatures of 1600°C to melt lunar regolith and dissociate the molten oxides. These conditions limit the use of many oxide refractory materials, such as Al2O3 and MgO, due to rapid degradation resulting from reactions between the refractory materials and molten lunar regolith. Yttria‐stabilized zirconia (YSZ) is shown here to be a promising refractory oxide to provide containment of molten regolith while demonstrating limited reactivity. This work focuses on corrosion studies of YSZ powders and dense YSZ crucibles in contact with molten lunar maria and highlands regolith simulants at 1600°C. The interactions between YSZ and molten regolith were characterized using scanning electron microscopy/energy dispersive spectroscopy, X‐ray diffraction, and electron backscatter diffraction. A FactSage thermochemical model was created for comparison with the experimental results. These combined analyses suggest that lunar maria regolith will degrade the YSZ faster than the lunar highlands regolith due to the lower viscosity of the maria regolith. The feasibility of long‐term molten regolith containment with YSZ is discussed based on the YSZ powder and crucible results.

Planetary Soil Simulant Characterisation: NU-LHT-2M Study Case to Support Oxygen Extraction Lab Tests with a Low-Temperature Carbothermal Process

Since the landing on the lunar surface, the lunar regolith has begun to interact in different ways with landed elements, such as the wheels of a rover, astronaut suits, drills, and plants for extracting oxygen or manufacturing objects. Therefore, a strong effort has been required on Earth to fully characterise these kinds of interactions and regolith utilisation methods. This operation can only be performed by using regolith simulants, soils that are reproduced with the Earth’s rocks and minerals to match the real features. This article presents the main guidelines and tests for obtaining the properties of a generic simulant in terms of composition, physical and mechanical properties, solid–fluid interaction, and thermal properties. These parameters are needed for the designing and testing of payloads under development for planned lunar surface missions. The same tests can be performed on lunar, martian, or asteroid simulants/soils, both in laboratory and in situ. A case study is presented on the lunar simulant NU-LHT-2M, representative of the lunar highlands. The tests are performed in the context of an in situ resource utilisation (ISRU) process that aims to extract oxygen from the lunar regolith using a low-temperature carbothermal reduction process, highlighting the main regolith-related criticalities for an in situ demonstrator plant.

Modeling electrolysis in reduced gravity: producing oxygen from in-situ resources at the moon and beyond

Molten Regolith Electrolysis, as an in situ resource utilization (ISRU) technology, has the potential to enable the production of oxygen and metallic alloys on the Lunar surface; opening new doors in Cis-Lunar, and eventually Martian space exploration. This research studies the fundamental physics which govern the formation, growth, detachment, and rise of electrolytic bubbles. To this end, computational fluid dynamic (CFD) models were developed and run, to simulate water electrolysis, molten salt electrolysis (MSE), and molten Lunar regolith (MRE) electrolysis across multiple reduced gravity levels. The results demonstrate that reduced gravity, electrode surface roughness (possibly due to surface degradation), fluid properties, and electrode orientation can all affect electrolytic efficiency and possibly even stall electrolysis by delaying bubble detachment. The findings of this research must be considered when designing and operating electrolysis systems at reduced gravity levels.

Optimized manufacturing process of homogeneous microwave-sintered blocks of KLS-1 lunar regolith simulant

The use of materials from the Moon's surface based on In-Situ Resource Utilization (ISRU) is gaining considerable attention as a means of constructing infrastructure to sustain a human presence there. In particular, the sintering of lunar regolith appears a promising way to fabricate infrastructure on the lunar surface. This study presents a method to manufacture homogeneous blocks using a lunar regolith simulant. The tested simulant, KLS-1, was sintered under diverse conditions in a multi-mode microwave sintering furnace. Successful sintering requires the sample to be heated throughout, without generating a temperature gradient. This was achieved by testing various heating rates and sample sizes. X-ray computed tomography was used to assess the pore structure of sintered samples. While the optimized sintering conditions resulted in the formation of internal cracks by outgassing, preheating the KLS-1 in a vacuum oven at 250 °C effectively prevented the formation of internal cracks. The homogeneity of the blocks was confirmed by coring and measurements of true density, bulk density, porosity, and unconfined compressive strength. The robust reproducibility and similarity in physical and mechanical properties validate the viability of microwave sintering in manufacturing large and uniform blocks suitable for application as construction materials on the Moon.

Unlocking the future of space resource management through satellite remote sensing and AI integration

This scientific study investigates how artificial intelligence (AI) and satellite remote sensing could work together to transform space resource management. As human activity in space continues to expand, the effective and sustainable utilization of celestial resources is of paramount importance. It begins by highlighting the evolution of space exploration and the growing interest in resource extraction beyond Earth's boundaries. It emphasizes the critical role of resource management for the success of future space missions.Advances in technology in recent times, including the implementation of in-situ resource utilization (ISRU) and self-governing mining systems, have significantly enhanced the possibility of extracting resources from celestial entities. While the economic feasibility of space mining is compelling, environmental concerns, sustainability, and intricate governance challenges necessitate careful examination.An approach for comprehending the complex field of space resource management is presented in this research. It delineates a clear roadmap of its content, offering a succinct summary of key objectives and sections, facilitating reader comprehension. The methodology includes a literature review of relevant research materials from Web of Science, Scopus, and Google Scholar sources. It investigates celestial bodies' resource potential, main challenges, and environmental implications.Preliminary contributions include one analysis of the potential applications of satellite remote sensing and AI technologies in mitigating these challenges, highlighting their pivotal roles in resource identification and management, proposing terrestrial solutions applicable to space resource management. The integration of AI into space resource management is discussed, emphasizing its potential to enhance safety protocols, resource allocation, and overall efficiency. Furthermore, it discusses international agreements and treaties governing space exploration and resource utilization while advocating for cooperation among space-faring nations and stakeholders. It concludes discussing the implications, benefits, challenges, areas requiring further attention, and future directions of integrating these technologies in space resource management.

LIBS for prospecting and Raman spectroscopy for monitoring: two feasibility studies for supporting in-situ resource utilization

Laser-induced breakdown spectroscopy (LIBS) and Raman spectroscopy are still rather new techniques for in-situ exploration of extraterrestrial planetary surfaces but have shown their suitability and great potential in several successful robotic missions already. Next to serving primary scientific applications, both methods can also be used in the context of in-situ resource utilization (ISRU) such as scouting for wanted substances and the surveillance of extraction processes. Here, we present two laboratory studies conducted in the context of ISRU with a focus on the chain from prospecting to extracting oxygen from lunar regolith. For LIBS, with optimized data processing and combined with state-of-the-art multivariate data analysis approaches, we show the potential of the technique for identifying samples with increased ilmenite content and for elemental quantification. The measurements were done using lunar regolith simulant and low pressures simulating vacuum on atmosphereless bodies such as the Moon. With Raman spectroscopy, we analyzed lunar regolith simulant samples that underwent electrochemical alteration for oxygen extraction and production of metal alloys demonstrating the potential of Raman spectroscopy for ISRU process monitoring. We also discuss the results in a broader context, evaluating the potential of both methods for other aspects of ISRU support.

Lunar simulant behaviour in molten fluoride salt for ISRU applications

This study investigated the behaviour of a lunar mare crystalline analog dissolved in molten LiF–NaF at 800 °C for the in situ production of metals as a part of In Situ Resource Utilization (ISRU) research. Molten fluorides have the capability to dissolve metallic oxides, and the Hall-Héroult process uses this kind of media to produce Al from Al2O3.The first step was to compare the individual solubility of the main oxides composing the mare lunar soil (SiO2, Al2O3, Fe2O3, and MgO) with the solubility of the crystalline analog using Inductively Coupled Plasma – Atomic Emission Spectroscopy (ICP-AES). The species concentration added jointly are lower than the concentration of the same species added separately. Nonetheless, this study showed that LiF–NaF can be used to dissolve the analog with a maximum solubility of 3.9 wt% at 800 °C. Cyclic voltammograms were also used to verify the electroactivity of all oxide species in LiF–NaF, wherein all the main oxides are electroactive except SiO2 and TiO2. Then electrolyses on different cathodic substrates were performed at different conditions and the obtained cathodic products were analysed with a scanning electron microscope (SEM) coupled with an energy dispersive spectroscopy (EDS). Despite the non-electroactivity of SiO2 and TiO2, they were extracted in an alloyed form through Under Potential Deposition (UPD). Metallic deposition of other metals such as aluminium and titanium was achieved on carbon electrode. Finally, a synthetic mixture made of the different oxide species with the same chemical composition as the simulant, was investigated as a viable substitute for lunar mare soil. Its electrochemical behaviour was identical to the crystalline lunar simulant showing that our original process based on oxides dissolution is not influenced by the amorphous/crystalline state of the raw material.the outputs of LiF–NaF molten process are not critically influenced by the physical state of the lunar regolith.

Verification of a virtual lunar regolith simulant

Introduction: Physical regolith simulants are valuable tools for developing In-Situ Resource Utilisation hardware. However, using virtual models of regolith instead can reduce costs, limit exposure to hazardous materials, and offer a practical method of testing the effects of reduced gravity.Methods: We verify a virtual model of regolith as macroparticles against physical tests. Using space partitioning techniques to identify neighbouring particles, we present a scalable model of regolith, in which the computation time increases roughly proportionally with the number of particles. We evaluated the performance of this virtual simulant vs. a physical simulant (Exolith LMS-1) by comparing the flow rate through funnels of various diameters, and the resultant angle of repose of material on both large (500 g) and small (16 g) scale tests.Results: For large scale tests, the flow rates were within the predicted range for macroparticles with radii 3–7 mm, with the greatest accuracy achieved for radii 4–5 mm. However, the macroparticles blocked the simulated funnels more easily than in the physical trials, due to their high cohesion. The angle of repose was not accurately represented by this model for either of the tests.Discussion: The high efficiency of this model makes it best suited for applications which require large scale approximations of regolith with real-time execution, such as virtual training for robot operators or providing visual and haptic feedback in model-mediated teleoperation systems. The results of this model in reduced gravity could be further verified against data from upcoming lunar missions in future work.

Characterization of High-priority Landing Sites for Robotic Exploration Missions in the Apollo Basin, Moon

The South Pole–Aitken (SPA) basin is the oldest and largest visible impact structure on the Moon, making it a high priority science site for exploration missions. The 492 km diameter Apollo peak-ring basin is one of the youngest and largest basins within the SPA basin. We selected three regions of interest (ROIs) in the Apollo basin for which the landing and operational hazards are minimized and evaluated their science and in situ resource utilization (ISRU) potential. We examined topography, slope, crater density, rock abundance, geologic mapping, mineralogy, and inferred subsurface stratigraphy within each ROI. The results show that the terrain is safe for landing without precision landing (within a few hundred meters). The mare materials have high ISRU potential with relatively high FeO (∼16–20 wt%) and TiO2 (∼3–10 wt%) contents. Two robotic exploration mission architectures were examined for their scientific potential: (1) lander and rover with a dedicated payload suite and (2) the same architecture with sample return capability. In situ observations can address six of seven National Research Council concepts (1–3, 5–7) and Campaigns 1 and 5 of the European Space Agency’s Strategy for Science at the Moon.

Modelling and optimization of a forced convection heat exchanger for Mars waste heat rejection for power cycle and cryocooling applications

A forced convection heat exchanger for waste heat rejection to the Martian atmosphere is modelled for both a power generation and cryogenic refrigeration application. The modeling is based on existing as well as recent, experimentally validated heat transfer and pressure drop correlations for low-Reynolds-number, moderate-Knudsen number finned tube arrays and represents the first detailed examination of optimal heat exchanger design and performance in this regime. These correlations were developed from heat exchanger performance data taken in Mars-like conditions and are described in a separate, companion work [1]. A heat exchanger model based on the effectiveness-NTU method is developed using these correlations and the heat exchanger geometry is optimized using an open-source solver to minimize the overall system mass for a range of candidate heat exchanger materials and heat transfer rates. The optimal heat exchangers generally consisted of shallow, staggered banks of 1–2 mm diameter tubes and 2–4 mm fin spacing, although in some conditions bare tube arrays were optimal. These geometries tended to be preferred due to their low relative pressure drop, a necessity given the power requirement of producing high pressure head in the thin atmosphere. Curve fits that capture the heat exchanger performance are generated based on the input conditions in order to develop a reduced order model that can be used to integrate the heat exchanger model with an existing recuperated Brayton cycle high-temperature gas cooled reactor (HTGR) power cycle model. This power cycle model is used to determine the impact of using convective heat rejection on optimal system mass and compare this approach to radiative heat rejection. For a 40 kWe power output, the optimal overall cycle mass is found to decrease by 78 % when using convective heat rejection compared to a radiator; this is due to the decreased mass of the heat rejection system as well as the lower optimal rejection temperature which results in a lower recuperator mass. The heat exchanger itself has a mass of only 37 kg, a frontal area of 12.7 m2, and requires 2134 W of fan power to operate. The system is shown to perform well over a wide range of Mars ambient conditions. A high-power liquid Oxygen (LOx) reverse Brayton cryocooler cycle is also modeled to determine the benefit of using convective heat rejection for in-situ resource utilization (ISRU) applications. Across a range of power source options and ambient temperatures, using a convective heat rejection system reduced total system mass by up to 43 % and frontal area by up to 95 % compared to a radiator and also reduced the mass-optimal cycle power draw by increasing the optimal cycle efficiency. However, the magnitude of the mass reduction depends strongly on the specific power of the electrical source; the forced convection system provides only a 7 % improvement over a radiator when coupled with a photovoltaic power source due to the increased power demand of the fan. Overall, this technology offers significant performance advantages over radiative heat rejection systems for waste heat rejection applications on Mars and therefore may significantly benefit future crewed Mars missions.

Mars In Situ Resource Utilization (ISRU) with Focus on Atmospheric Processing for Near-Term Application—A Historical Review and Appraisal

The inspirational paper by Ash, Dowler, and Varsi in 1978, proposing to utilize in situ resources on Mars (ISRU) rather than bringing them from Earth, originated the field of Mars ISRU that has been the subject of research ever since. In this paper, we reviewed significant research reported on Mars ISRU since 1978 and reported briefly on accomplishments. We found that prior to 2014, progress on small tasks was sporadic and intermittent, always at low Technology Readiness Level (TRL). In 2014, the National Aeronautics and Space Administration (NASA) took a bold, imaginative, unprecedented step to fund a major project in Mars ISRU: the so-called “MOXIE” (Mars Oxygen In Situ Experiment), in which an oxygen production plant based on solid oxide electrolysis (SOEC) was developed, and finally demonstrated on Mars in 2022 and 2023. While MOXIE leaves behind it a wealth of accomplishments, there remains the need to close remaining gaps with additional laboratory and field work. Solid-oxide electrochemical cell (SOEC) technology has become a major area of worldwide investment for terrestrial energy and CO2 control. There is a very strong overlap between this terrestrial technology and Mars ISRU. NASA has already leveraged the terrestrial development work via MOXIE. NASA can leverage further advances with a comparatively small investment beyond 2023. Because NASA is engaged in a major program to return humans to the Moon, NASA’s focus is on lunar ISRU. Unfortunately, the mission impact and return on investment for lunar ISRU does not compare to that for Mars ISRU. NASA’s concept for Mars ISRU is futuristic, involving autonomous mining, transporting, and processing large amounts of Mars regolith. This might well occur long after initial human landings which could better profit in the near-term from MOXIE technology. By continuing further development of SOEC technology beyond MOXIE, while leveraging large investments in terrestrial applications, NASA can develop the Mars ISRU appropriate to nearer term human missions at modest investment. The goal of this paper is to place the relatively mature MOXIE technology advance and solid oxide electrolysis in general in perspective to the historical evolution of low TRL Mars ISRU technology.

Optimizing lunar regolith beneficiation for ilmenite enrichment

Over the past few years, the international space industry has focused extensively on advancing technologies to enable prolonged human space exploration missions. The primary limiting factor for these endeavors is the spacecraft’s capacity to transport and store essential supplies from Earth to support human life and mission equipment throughout the mission’s duration. In-situ resource utilization (ISRU) is the preferred solution for this challenge. Previous lunar missions have identified the presence of oxygen within the lunar regolith, which is an important resource for human space exploration missions. Oxygen is present in many different minerals within the lunar regolith out of which, ilmenite provides the highest yield of oxygen per unit mass using hydrogen reduction. However, the distribution of ilmenite is neither high nor uniform throughout the lunar surface and therefore, needs beneficiation, which is an important intermediate step for ilmenite-based oxygen production. A regolith beneficiation testbed was developed at DLR Bremen which is a TRL 4 level representation of the technology. The testbed has multiple process parameters that can be adjusted to produce the desired feedstock. This work focuses on the optimization of this testbed to produce a feedstock with higher ilmenite content than the input regolith. The testbed comprises three beneficiation techniques, viz. gravitational, magnetic and electrostatic beneficiation that work sequentially to produce the desired feedstock. The optimized parameter configuration achieved up to three-fold increase in the ilmenite grade relative to the input with about 32 wt% of the total ilmenite being recovered in the enriched output. These experiments have highlighted other underlying factors that influenced the experimental research such as the design of testbed components, system residuals and limited availability for Off-the-shelf components. The observations made from these experiments have also provided insights into the further development of the technology. The work has thus produced evidence for the effectiveness of the beneficiation testbed in producing an enriched feedstock while outlining avenues for future improvements.

Lunar polar volatile remobilization in regolith-filled craters

Under lunar polar cold traps, volatile molecules within porous regolith may experience temperature and depth dependent slow mobility. Many degraded lunar craters exhibit thick regolith fill based on models of topographic diffusion and observations of fresh and degraded craters. Regolith has a low thermal conductivity relative to megaregolith and may act as a blanket for internal lunar heat flow, leading to increased temperatures at depth. We develop 2D thermal models of fresh and regolith-filled lunar craters over depths of meters to hundreds of meters below the surface. We find that the base of the stability and slow mobility zones migrate upward with regolith fill, which leads to temperatures that may increase the sublimation rate of volatiles at depth. For a notional cold trap crater 1.6 km in diameter and 3.6 billion years old, topographic diffusion fills it with approximately 90 m of regolith, and the regolith fill's blanketing effect causes the 110 K isotherm to shift about 180 m upward. This places it approximately 25 m below the current cold trap surface and well above the initial crater floor. The slow water ice mobility zone below the 110 K isotherms also shifts upward with regolith fill, potentially increasing volatile concentrations at shallower depths. These secondary volatile concentrations may be targets for sampling and testing hypotheses of volatile system processes. In addition, remobilized volatile concentrations may be a resource for future In-Situ Resource Utilization (ISRU) applications. The thick regolith fill in degraded craters and volatile remobilization potential in lunar subsurface cold traps have implications for future exploration instruments, sampling, and ISRU architectures.

Plasma-based conversion of martian atmosphere into life-sustaining chemicals: The benefits of utilizing martian ambient pressure

We explored the potential of plasma-based In-Situ Resource Utilization (ISRU) for Mars through the conversion of Martian atmosphere (∼96% CO2, 2% N2, and 2% Ar) into life-sustaining chemicals. As the Martian surface pressure is about 1% of the Earth’s surface pressure, it is an ideal environment for plasma-based gas conversion using microwave reactors. At 1000 W and 10 Ln/min (normal liters per minute), we produced ∼76 g/h of O2 and ∼3 g/h of NOx using a 2.45 GHz waveguided reactor at 25 mbar, which is ∼3.5 times Mars ambient pressure. The energy cost required to produce O2 was ∼0.013 kWh/g, which is very promising compared to recently concluded MOXIE experiments on the Mars surface. This marks a crucial step towards realizing the extension of human exploration.

Character and spatial distribution of mineralogy at the lunar south polar region

The lunar south polar region, encompassing part of the South Pole-Aitken (SPA) basin, stands out as one of the most intriguing areas for future lunar exploration endeavors. Using the Moon Mineralogy Mapper (M3) data, we conducted a comprehensive investigation into the characteristics and distribution of minerals within the lunar south polar region, spanning from 80°S to the south pole. The cartographic outputs from this study, capable of delineating the composition and abundance of various minerals, have enabled the partitioning of the lunar south polar region into two distinct zones. The region situated within the inner ring of the SPA basin is characterized by an elevated abundance of low-Ca pyroxene, whereas the Feldspathic Highlands (FH) in the lunar south polar region and the outer ring of the SPA basin predominantly comprise feldspathic materials, albeit with localized pyroxene-rich areas. The dominant mafic component across the lunar south polar region is low-Ca pyroxene, with no evidence of olivine-rich materials being detected. The mineralogy of some candidate landing sites was illustrated and the hematite-bearing materials were observed at the rim of Shackleton and de Gerlache. Furthermore, we also identified an abundance plagioclase on the western rim of Shackleton. These findings underscore the significance of the lunar south polar region, not only as a promising locale for in situ resource utilization (ISRU) in forthcoming lunar missions but also as a key site for advancing our understanding of the Moon's geological evolution.

Material aspects of sintering of EAC-1A lunar regolith simulant

Future lunar exploration will be based on in-situ resource utilization (ISRU) techniques. The most abundant raw material on the Moon is lunar regolith, which, however, is very scarce on Earth, making the study of simulants a necessity. The objective of this study is to characterize and investigate the sintering behavior of EAC-1A lunar regolith simulant. The characterization of the simulant included the determination of the phase assemblage, characteristic temperatures determination and water content analysis. The results are discussed in the context of sintering experiments of EAC-1A simulant, which showed that the material can be sintered to a relative density close to 90%, but only within a very narrow range of temperatures (20–30 °C). Sintering experiments were performed for sieved and unsieved, as well as for dried and non-dried specimens of EAC-1A. In addition, an analysis of the densification and mechanical properties of the sintered specimens was done. The sintering experiments at different temperatures showed that the finest fraction of sieved simulant can reach a higher maximum sintering temperature, and consequently a higher densification and biaxial strength. The non-dried powder exhibited higher densification and biaxial strength after sintering compared to the dried specimen. This difference was explained with a higher green density of the non-dried powder during pressing, rather than due to an actual influence on the sintering mechanism. Nevertheless, drying the powder prior to sintering is important to avoid the overestimation of the strength of specimens to be fabricated on the Moon.

(Invited) Utilization of Bio-CO2 and Bio-Methane for Fuel Production: Integration Solid Oxide Electrolyzer, Low Energy Plasma Reformer with Fischer-Tropsch Synthesis

Transition to renewable energy is essential to achieve climate protection objectives. Besides storing electricity for later use, fuel production using renewable energy is an essential part of reducing fossil dependance. Hydrogen production is receiving the greatest attention as a carbon free energy carrier with the potential to fuel future fleets of hydrogen fuel cell vehicles, to store grid electricity to accommodate asynchronous generation and load, and to a lesser extent to displace heating fuels. However, the highest value application in current markets is the production of liquid transportation fuels such as sustainable aviation fuels (SAF) and low (fossil) carbon diesel fuel. However, liquid hydrocarbon fuels only achieve the decarbonization goals if they displace fossil fuels and are produced from sustainable, ideally biogenic carbon resources.Solid oxide electrolysis cell (SOEC) stack developed by OxEon team for MOXIE, the Mars OXygen ISRU Experiment has demonstrated the use of CO2 as an electrolysis feedstock aboard the Perseverance rover which as of this writing has operated thirteen times on Mars, splitting the Mars atmosphere CO2 to carbon monoxide and oxygen, as the first ever demonstration of In Situ Resource Utilization (ISRU) on another planet. The technology is applicable to efficient resource utilization on this world and OxEon is actively developing power to fuels technology to maximize the conversion of biogenic carbon to high value, energy dense, liquid transportation fuels that are needed by an existing vehicle fleet that will be on the road and in the air decades to come.OxEon’s technologies are being applied to bridge the electrical and materials energy sectors. In this project OxEon processes the bio-CO2 through an SOEC and the bio-CH4 through a low energy plasma reformer. The combined synthesis gas is supplied to a Fischer-Tropsch reactor. The combination offers several advantages: the yield of biofuel nearly doubles by use of the bio-CO2 compared to the bio-methane alone, cooling the FT reactor generates all the steam needed in the SOEC system reducing the effective operating voltage (accounting for raising steam) from > 1.5 V/cell to < 1.3 V/cell, oxygen by-product from the SOEC is used in the autothermal reformer, as is some of the FT produced water. The product fuel is all bio-carbon, but it also embodies renewable electric energy in a high-value, storable and transportable liquid hydrocarbon that will be usable in the current air and ground fleets.

Electrochemical Peroxide Generation for in Situ Disinfection

Among the numerous technological advances sought in order to facilitate human exploration and habitation outside of earth’s atmosphere, solutions and innovations are needed for processing resources locally to support sustainable and long duration space missions. Such in-situ resource utilization (ISRU) is aimed at reducing the payload mass during launch and eliminate the need for ground support for long-term missions and ultimately space colonization. Disinfection needs is an area of particular need, which is currently accomplished through the use of pre-packaged, disposable, wetted disinfection wipes. These items represent an appreciable carry-along mass and disposal/replacement burden requiring ground support. Therefore, a system is desired that could utilize onboard utilities to create disinfecting solutions to eliminate storage/disposable problems of the wetted wipes and further reduce the astronaut’s dependence on earth-based supplies.Faraday Technology Inc. is addressing this challenge by demonstrating an in-situ approach, which utilizes on-board supplies of air and water for on demand electrochemical generation of hydrogen peroxide. Hydrogen peroxide is well-established disinfectant with non-toxic decomposition products (viz., O2 and H2O), that is safe enough for human contact to be sold commercially as a 1-5 w/w% solution, which makes it an ideal disinfecting solution for closed space environments. Faraday has continued to improve the TRL by scaling the electrochemical peroxide generation system from a sub-scale to alpha-scale process in order to deliver 1 L per day of ~2 w/w% hydrogen peroxide for disinfectant applications from DI water feed-stream with air as a feed source[1],[2],[3],[4]. These electrolytes were then sent to NASA for microbial control property characterization.This system eliminates the need to ferry disinfectant wipes to manned space capsules and is a critical enabling technology for future moon-based missions and beyond. Specifically, this talk will discuss the results of these advancements. Acknowledgements: Financial support of NASA Contracts NNX16CA43P, NNX17CJ12C, 80NSSC20C0070, and 80NSSC23CA036 is acknowledged.