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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

A Bifunctional Ionic Liquid for Capture and Electrochemical Conversion of CO 2 to CO over Silver

Electrochemical conversion of CO 2 requires selective catalysts and high solubility of CO 2 in the electrolyte to reduce the energy requirement and increase the current efficiency. In this study, the CO 2 reduction reaction (CO 2 RR) over Ag electrodes in acetonitrile-based electrolytes containing 0.1 M [EMIM][2-CNpyr] (1-ethyl-3-methylimidazolium 2-cyanopyrolide), a reactive ionic liquid (IL), is shown to selectively (>94%) convert CO 2 to CO with a stable current density (6 mA·cm –2 ) for at least 12 h. The linear sweep voltammetry experiments show the onset potential of CO 2 reduction in acetonitrile shifts positively by 240 mV when [EMIM][2-CNpyr] is added. This is attributed to the pre-activation of CO 2 through the carboxylate formation via the carbene intermediate of the [EMIM] + cation and the carbamate formation via binding to the nucleophilic [2-CNpyr] – anion. The analysis of the electrode–electrolyte interface by surface-enhanced Raman spectroscopy (SERS) confirms the catalytic role of the functionalized IL where the accumulation of the IL-CO 2 adduct between –1.7 and –2.3 V vs Ag/Ag + and the simultaneous CO formation are captured. Furthermore, this study reveals the electrode surface species and the role of the functionalized ions in lowering the energy requirement of CO 2 RR for the design of multifunctional electrolytes for the integrated capture and conversion.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1977

Extraction processes for the production of aluminum, titanium, iron, magnesium, and oxygen and nonterrestrial sources

The suitability of existing terrestrial extractive metallurgical processes for the production of Al, Ti, Fe, Mg, and O2 from nonterrestrial resources is examined from both thermodynamic and kinetic points of view. Carbochlorination of lunar anorthite concentrate in conjunction with Alcoa electrolysis process for Al; carbochlorination of lunar ilmenite concentrate followed by Ca reduction of TiO2; and subsequent reduction of Fe2O3 by H2 for Ti and Fe, respectively, are suggested. Silicothermic reduction of olivine concentrate was found to be attractive for the extraction of Mg becaue of the technological knowhow of the process. Aluminothermic reduction of olivine is the other possible alternative for the production of magnesium. The large quantities of carbon monoxide generated in the metal extraction processes can be used to recover carbon and oxygen by a combination of the following methods: (1) simple disproportionation of CO,(2) methanation of CO and electrolysis of H2O, and (3) solid-state electrolysis of gas mixtures containing CO, CO2, and H2O. The research needed for the adoption of earth-based extraction processes for lunar and asteroidal minerals is outlined.

D Bhogeswara Rao↗
NASA NTRS1982

An integrated regenerative air revitalization system for spacecraft

Progress towards development of an air revitalization system (ARS) for spacecraft breathable atmosphere regeneration is assessed, and a preliminary design for a one-person ARS is described. The ARS is considered a necessary component of any permanently manned orbital station, and studies have demonstrated that penalties for expendable air supplies justify an ARS for missions longer than 40 days. CO2 must be removed and O2 returned along with N2, which can be extracted from hydrazine, with the H2 component returning to the operation of the CO2 reduction subsystem. An experimental ARS (ARX-1) features a cabin humidity control unit, a CO2 concentrator, an air-cooled CO2 reduction reactor, an oxygen generator (electrolysis), the hydrazine N2 generator, and a water handling unit. A 120-day test demonstrated one-button startup and 480 hr operation in a normal mode.

Noyes, G. P.↗
NASA NTRS1983

Integrated atmosphere revitalization system description and test results

The design and operation of several air revitalization subsystems are described, along with the testing of these subsystems separately and integrated in an air revitalization system for use in space stations. The subsystems are: one that generates O2 by water electrolysis, one that removes and concentrates CO2 using an electrochemical technique, and one that reduces concentrated CO2 by the Sabatier process. Results of the integrated testing include the observations that liquid cooling should be baselined for recovery of the CO2 reduction subsystem product water, continuous CO2 injection into the air supply unit is preferable, small changes in the current CO2 removal subsystem inlet PCO2 are detectable as changes in the CO2 reduction subsystem reactor temperatures, and hardwired shutdown of critical parameters is vital if computer-based controllers are not redundant. Several block diagrams are provided.

Martin, R. B.↗
DOE OSTI2021

Flow-through reactor for electrocatalytic reactions

A flow-through electrolysis cell includes a hierarchical nanoporous metal cathode. A method of reducing CO2 includes flowing the CO2 through the hierarchical nanoporous metal cathode of the flow-through electrolysis cell.

Biener, Monika M.↗
NASA NTRS1976

Integration of the electrochemical depolorized CO2 concentrator with the Bosch CO2 reduction subsystem

Regenerative processes for the revitalization of spacecraft atmospheres require an Oxygen Reclamation System (ORS) for the collection of carbon dioxide and water vapor and the recovery of oxygen from these metabolic products. Three life support subsystems uniquely qualified to form such an ORS are an Electrochemical CO2 Depolarized Concentrator (EDC), a CO2 Reduction Subsystem (BRS) and a Water Electrolysis Subsystem (WES). A program to develop and test the interface hardware and control concepts necessary for integrated operation of a four man capacity EDC with a four man capacity BRS was successfully completed. The control concept implemented proved successful in operating the EDC with the BRS for both constant CO2 loading as well as variable CO2 loading, based on a repetitive mission profile of the Space Station Prototype (SSP).

Schubert, F. H.↗
DOE OSTI2021

The Modeling of Synfuel Production Process: ASPEN Model of FT production with electricity demand provided at LWR scale

Synfuels, or electro-fuels (e-fuels) have the unique potential to significantly reduce greenhouse gas (GHG) emissions across the transportation sector. This is especially true for applications with substantial payloads and daily miles traveled, such as long-haul heavy-duty vehicles, rail locomotives, marine vessels and aviation aircrafts that are challenging to directly electrify via battery or fuel cell powertrain technologies. Synfuels, or electro-diesel/electro-jet fuels, have similar properties with the incumbent petroleum fuels, compatible with current infrastructure but have much lower GHG emissions relative to the petroleum counterpart, because they utilize waste carbon dioxide (CO2) streams and green hydrogen (H2) sourced from electrolysis. To achieve substantial reductions in GHG emissions, electricity sources must be zero carbon or near-zero carbon, which is the case with solar, wind, hydro and nuclear power. Compared to the intermittency of solar, wind and hydro, nuclear energy provides a steady energy source. In addition, it’s advantageous for nuclear power to produce synfuels because it provides not only near-zero carbon electricity to displace grid electricity, but also near-zero carbon steam to displace carbon-intensive natural gas combustion for steam generation. The availability of electricity and steam also enables more efficient green hydrogen production by using high-temperature electrolysis. In this work, Argonne National Laboratory (ANL) models a synfuel production process via the Fischer- Tropsch (FT) reaction by using nuclear power to provide electricity and steam. In 2021, using ASPEN Plus software, ANL established a detailed process model of a stand-alone FT production facility, assuming feedstocks of pure CO2 and H2. This stand-alone model can be expanded to integrate H2 production from nuclear power via low-temperature and high-temperature electrolysis at light-water reactor (LWR) scale. This report summarizes the stand-alone ASPEN Plus model results with a detailed mass and energy analysis. Our modeled facility produces 351 MT/day (130,000 gal/day) of FT fuel (a mixture of naphtha, jet fuel, and diesel) by converting 223 MT/day of H2 and 2,387 MT/day of CO2. The FT fuel production energy efficiency is 58% and the carbon conversion efficiency (from CO2 to FT fuel) is 46%. The production of green hydrogen requires 390–470 MWe of electricity, which is compared with the capacity of an LWR plant. For the stand-alone FT process, the detailed energy demand (electricity and heat) is summarized in the table below. Based on the energy supply source and the required temperature, potential insertion points of nuclear energy are identified. Based on the potential nuclear energy utilization, this report discusses potential modification options for expanding the system boundary to integrate nuclear power use, for example on-site hydrogen production via water electrolysis. Modeling of the integrated system is conducted by closely working with ANL and Idaho National Laboratory (INL) collaborators to harmonize design parameters of nuclear plants and the FT production process.

Zang, Guiyan↗
NASA NTRS2001

A Survey of Alternative Oxygen Production Technologies

Utilization of the Martian atmosphere for the production of fuel and oxygen has been extensively studied. The baseline fuel production process is a Sabatier reactor, which produces methane and water from carbon dioxide and hydrogen. The oxygen produced from the electrolysis of the water is only half of that needed for methane-based rocket propellant, and additional oxygen is needed for breathing air, fuel cells and other energy sources. Zirconia electrolysis cells for the direct reduction of CO2 arc being developed as an alternative means of producing oxygen, but present many challenges for a large-scale oxygen production system. The very high operating temperatures and fragile nature of the cells coupled with fairly high operating voltages leave room for improvement. This paper will survey alternative oxygen production technologies, present data on operating characteristics, materials of construction, and some preliminary laboratory results on attempts to implement each. Our goal is to significantly improve upon the characteristics of proposed zirconia cells for oxygen production. To achieve that goal we are looking at electrolytic systems that operate at significantly lower temperatures, preferably below 31C to allow the incorporation of liquid CO2 in the electrolyte. Our preliminary results indicate that such a system will have much higher current densities and have simpler cathode construction than a porous gas feed electrode system. Such a system could be achieved based on nonaqueous electrolytes or ionic liquids. We are focusing our research on the anode reaction that will produce oxygen from a product generated at the cathode using CO2 as the feed. Operation at low temperatures also will open up the full range of polymer and metal materials, allowing a more robust system design to withstand the rigors of flight, landing, and long term unattended operation on the surface of Mars.

Lueck, Dale E.↗
NASA NTRS2000

A Survey of Alternative Oxygen Production Technologies

Utilization of the Martian atmosphere for the production of fuel and oxygen has been extensively studied. The baseline fuel production process is a Sabatier reactor, which produces methane and water from carbon dioxide and hydrogen. The oxygen produced from the electrolysis of the water is only half of that needed for methane-based rocket propellant, and additional oxygen is needed for breathing air, fuel cells and other energy sources. Zirconia electrolysis cells for the direct reduction of CO2 are being developed as an alternative means of producing oxygen, but present many challenges for a large-scale oxygen production system. The very high operating temperatures and fragile nature of the cells coupled with fairly high operating voltages leave room for improvement. This paper will survey alternative oxygen production technologies, present data on operating characteristics, materials of construction, and some preliminary laboratory results on attempts to implement each.

Lueck, Dale E.↗
NASA NTRS2018

Plasma Methane Pyrolysis for Spacecraft Oxygen Loop Closure

Life support is a critical function of any crewed space vehicle or habitat. Human life support systems on the International Space Station (ISS) include a number of atmosphere revitalization (AR) technologies to provide breathable air and a comfortable living environment to the crew. The Trace Contaminant Control System removes harmful volatile organic compounds and other trace contaminants from the circulating air. The Carbon Dioxide Removal Assembly (CDRA) removes metabolic carbon dioxide (CO2) and returns air to the cabin. Humidity is kept at comfortable levels by a number of condensing heat exchangers. The Oxygen Generation Assembly (OGA) electrolyzes water to produce oxygen for the crew and hydrogen (H2) as a byproduct. A Sabatier reaction-based CO2 Reduction Assembly (CRA) was launched to the ISS in 2009 and became fully operational in June 2011.The CRA interfaces with both the OGA and CDRA. Carbon dioxide from the CDRA is compressed and stored in tanks until hydrogen is available from OGA water electrolysis. When the OGA is operational and there is CO2 available, the CRA is activated and produces methane and water via the Sabatier reaction shown in Equation 1... One approach to achieve these higher recovery rates builds upon the ISS AR architecture and includes adding a methane post-processor to recover H2 from CRA methane. NASA has been developing the Plasma Pyrolysis Assembly (PPA) to fill the role of a methane post-processor.

Greenwood, Z. W.↗
NASA NTRSDate not supplied

Modeling Electrolytic O2 Recovery from Metabolic CO2 for Advanced Closed Loop Life Support Systems in Extraterrestrial Human Missions

The International Space Station (ISS) is currently equipped with a complex, heavy, and power consuming system that recovers approximately 50% of O2 from metabolic CO2. Future long duration human missions to the Moon and Mars will necessitate a sustainable and highly efficient metabolic oxygen recovery system capable of yielding a minimum of 75% O2 recovery. A Macrofluidic Electrochemical Reactor (MFECR) technology development effort is currently underway at NASA Marshall Space Flight Center (MSFC) to significantly increase current metabolic O2 recovery efficiency, expand mission sustainability, and reduce complexity of the system. The novel design combines CO2 conversion to O2 along with C2H4 as byproduct and water electrolysis (currently conducted in two separate units) into a single compact unit that runs at standard conditions and is theoretically capable of generating O2 with a theoretical maximum metabolic CO2 conversion of 73% while consuming less than metabolic water. This paper presents a comprehensive multi-physic 3D model developed at MSFC on CO2 conversion to O2 and C2H4 at standard conditions via MFECR. The 3D spatial domain of the model is a replica of the actual MFECR’s 3D drawing generated for the MFECR fabrication and operated to recover O2 from CO2 yielding C2H4 as byproduct. Electrochemical (EC) physics that includes EC multicomponent reaction mechanisms, mass transport, and electrical current density distributions is coupled in the model with all the other physics phenomena involved in the MFECR’s process, such as two-phase flow, free and porous fluid regimes, multicomponent mass transfer, heat transfer, and DC electrical current generation along with Joule heating effect. The EC reaction sections of the MFECR consists of two porous gas diffusion electrodes (GDE) and an electrolyte serpentine channel sandwiched in the middle. The CO2 feeds the cathode serpentine channel and part of the O2 product is fed back to the anode serpentine chamber. An alkaline solution feeds the electrolyte serpentine chamber wetting the GDEs of both, the anode and cathode allowing the OH- ionic transport between them. The EC reactions in the cathode’s GDE yield C2H4 from CO2 and H2 from water while the EC reaction in the anode’s GDE yields O2. The authors will present in this paper the validation of the model using experimental data and the utilization of the validated model in building a reliable simulator that will not only assist the authors on the MFECR design but also the optimization of its operation in the ISS and future spatial human missions.

Jesus A Dominguez↗
DOE OSTI2025

Catalysis: Volume 36 (Preface)

This volume reviews the extensive literature published in the area of microwave-assisted catalytic approaches for waste conversion, non-reductive CO2 conversion, CO₂ utilization, heterogeneous catalysis and its integration with solid oxide electrolysis cell (SOEC) systems for chemical production, mechanistic pathways in ethylene epoxidation.

CO2 utilization↗
DOE OSTI2022

A Novel Process for Carbon Dioxide Conversion to Fuel

In this project, TDA developed a new mixed metal oxide-based sorbent that converts CO2 (captured from coal fired power plants) to CO, which can then be combined with renewable H2 generated by water electrolysis or H2 from steam methane reforming to produce different liquid fuels. TDA’s absorbent-based CO2 conversion process uses a redox process, which splits the catalytic reforming of methane with CO2 reaction into two stages: CO2 reduction to CO and CH4 reforming into H2 and CO which eliminates the equilibrium limitations. The CO produced in the two-stage reactor system can then be further reacted with renewable H2 to produce methanol, naphtha, diesel, or gasoline. We worked with the Advanced Power & Energy Program (APEP) of University of California, Irvine (UCI) to design and develop the liquid fuel synthesis process that is built around this new material. We demonstrated the techno-economic viability of the new sorbent based redox process to convert CO2 into synthesis gas by demonstrating continuous carbon dioxide reduction in a prototype test system for over 585 hours while converting up to 10 kg CO2/day. With the successful completion of the R&D effort, the technology is now ready for a larger pilot-scale demonstration and the technology readiness has been raised from TRL 3 to TRL 5. In collaboration with UCI, we completed a high-fidelity process design and economic analysis. The required sale price (RSP) for gasoline (Case 1 NG-MTG) is $4.91/gal and naphtha and diesel (Case 2 NG-FT) are $4.23/gal and $6.07/gal, respectively, on a 2011 dollar basis. To put these costs in perspective, the California prices in current dollars (with its strict specifications) for regular grade gasoline from last year to current year have varied from a low of $3.10/gal in January 2021 to a high of $5.76/gal in March 2022, while prices for diesel from last year to current year have varied from a low of $3.40/gal in January 2021 to a high of $6.41/gal in May 2022 according to the U.S. Energy Information Agency data. It should be noted that the gasoline and diesel produced by these designs of Case 1 and Case 2 would be of very high quality and both nitrogen and sulfur free. These RSPs are based on a cost of imported electricity of $64/MWh based on the low-end current wind generated electricity cost (Genevieve 2011). This cost is by far the largest component of the variable costs used in computing the RSPs. A sensitivity analysis of these RSPs to the cost of imported electricity shows that the cost of the imported electricity has a significant effect on the RSPs. The life cycle analysis (LCA) shows that the total cradle-to-gate CO2 emissions for both liquid fuels (diesel and gasoline) were negative, indicating that overall more CO2 is consumed than released during production of the fuel from CO2 feed stack for both cases (-296 kgCO2 per MT gasoline for Case 1 and -705 kgCO2 per MT diesel for Case 2). On a cradle-to-grave comparison, the use of diesel produced using TDA’s process (2,457 kgCO2 per MT diesel) would release 37.6% less CO2 compared to petroleum based diesel (3,937 kgCO2 per MT diesel) while the use of gasoline produced using TDA’s process (2,792 kgCO2 per MT gasoline) would release 29.3% less CO2 compared to petroleum based gasoline (3,946 kgCO2 per MT gasoline). With the successful completion of the R&D effort, the technology is now ready for a bench-scale demonstration and the technology readiness has been raised from TRL 3 (Analytical and experimental critical function and/or characteristic proof of concept) to TRL 5 (Laboratory scale similar system validation in relevant environment).

20 FOSSIL-FUELED POWER PLANTS↗
NASA NTRS1999

Fabrication and Performance of Zirconia Electrolysis Cells for Cabon Dioxide Reduction for Mars In Situ Resource Utilization Applications

Use of the Martian atmosphere (95% CO2) to produce oxygen (for propellant and life support) can significantly lower the required launch mass and dramatically reduce the total cost for Mars missions. Zirconia electrolysis cells are one of the technologies being considered for oxygen generation from carbon dioxide in Mars In Situ Resource Utilization (ISRU) production plants. The attractive features of the zirconia cell for this application include simple operation and lightweight, low volume system. A zirconia electrolysis cell is an all-solid state device, based on oxygen-ion conducting zirconia electrolytes, that electrochemically reduces carbon dioxide to oxygen and carbon monoxide. The cell consists of two porous electrodes (the anode and cathode) separated by a dense zirconia electrolyte. Typical zirconia cells contain an electrolyte layer which is 200 to 400 micrometer thick. The electrical conductivity requirement for the electrolyte necessitates an operating temperature of 9000 to 10000C. Recently, the fabrication of zirconia cells by the tape calendering has been evaluated. This fabrication process provides a simple means of making cells having very thin electrolytes (5 to 30 micrometers). Thin zirconia electrolytes reduce cell ohmic losses, permitting efficient operation at lower temperatures (8000C or below). Thus, tape-calendered cells provides not only the potential of low temperature operation but also the flexibility in operating temperatures. This paper describes the fabrication of zirconia cells by the tape calendering method and discusses the performance results obtained to date.

Minh, N. Q.↗
NASA NTRS1992

The feasibility of processes for the production of oxygen on the moon

An evaluation of the perceived feasibility of 20 different processs for the production of oxygen on the moon is presented. Many of them are largely untested and/or extremely complicated and difficult to implement. Simplicity, low energy, easily attainable feedstock, and resupply mass are the principal criteria for the processes that will ultimately be selected for the initial production of oxygen on the moon. An evaluation of the 20 processes resulted in a ranking according to overall feasibility. The eight processes considered to be the most likely candidates, at this time, for oxygen production on the moon are: ilmenite reduction of H2, CO2, and CH4; glass reduction with H2; molten silicate electrolysis; fluxed molten silicate electrolysis; vapor pyrolysis; and ion plasma pyrolysis.

Taylor, Lawrence A.↗
NASA NTRS1999

Fabrication and Performance of Zirconia Electrolysis Cells for Carbon Dioxide Reduction for Mars In Situ Resource Utilization Applications

The use of the Martian atmosphere (95% CO2) to produce oxygen (for propellant and life support) can significantly lower the required launch mass and dramatically reduce the total cost for Mars missions. Zirconia electrolysis cells are one of the technologies being considered for oxygen generation from carbon dioxide in Mars In Situ Resource Utilization (ISRU) production plants. The attractive features of the zirconia cell for this application include simple operation and lightweight, low volume system.

Minh, N. Q.↗