Results for “electrochemical CO 2 reduction”

NASA NTRS2024

Reliable and Efficient Electrochemical Recovery of O 2 from Metabolic CO 2 at the International Space Station (ISS)

Maximum O 2 recovery from metabolic carbon dioxide (CO 2 ) is desired for future long-duration missions beyond Low Earth Orbit (LEO). The O 2 recovery for the Environmental Control and Life Support System (ECLSS) at the International Space Station (ISS), presently limited to 50% (Sabatier), must be highly reliable and efficient and recover a minimum of 75% oxygen (O 2 ) from metabolic CO 2 . An alternative technology development effort currently underway at NASA Marshall Space Flight Center (MSFC) via a Microfluidic Electrochemical Reactor (MFECR) approach has the potential to increase O 2 recovery significantly and reduce the complexity of the ECLSS O 2 recovery at the ISS as it would replace three pieces, the CO 2 Reduction Assembly (CRA) (Sabatier reactor), the Oxygen Generation Assembly (OGA), and the Plasma Pyrolysis Assembly (PPA). The MFECR's electrochemical process generates ethylene (C 2 H 4 ) and carbon moxide (CO) instead of methane (CH 4 ) (Sabatier) as a byproduct, eliminating the need for further dehydrogenation through the PPA. As in the OGA, the MFECR's electrochemical process generates O 2 and hydrogen (H 2 ) from the water electrolysis process. MSFC and the University of Texas in Arlington (UTA) have jointly designed and fabricated an MFECR's single cell that operates at ambient conditions and utilizes a proprietary catalysis highly selective on reducing CO 2 to C 2 H 4 and CO at the cathode. This MFECR's single cell consists of gas diffusion layers at the cathode and anode for respective intake of CO 2 and output of O 2 from the catalytic layer. This approach is expected to substantially improve the ISS ECLSS sustainability and reduce power and weight requirements as the MFECR would replace three units currently installed in the ISS. In this paper, the authors discuss the outcome of preliminary tests, the current development, and the evaluation efforts on different alternatives for the cathode and the anode configurations, the setup of the MFECR at an engineering development unit (EDU) scale, and the O 2 recovery performance, and evaluation efforts on different alternatives on not only the configuration and setup of the MFECR at an Engineering Design Unit (EDU) scale but also the selection of component materials.

Jesus A Dominguez↗

NASA NTRSDate not supplied

CO2-Based Manufacturing System for Recombinant Protein Production

Space biomanufacturing is a potential In Situ Resource Utilization (ISRU) strategy to provide critical consumables and products while minimizing the launched mass for long-duration, deep space missions. On Earth, the primary biological conversion of CO 2 to biomass is through photosynthesis, and sugars from photosynthetic organisms are used as feedstocks for microbial biomanufacturing. The efficiency of non-biological reduction of CO 2 to organic molecules, such as acetate or ethanol, has greatly increased in recent years. We are designing a biomanufacturing system to rely on electrochemical CO 2 conversion products for carbon substrates to support microbial growth and production of recombinant proteins. The preliminary design includes a gas-permeable membrane bioreactor with dry salts that are rehydrated and mixed with the carbon source to support growth of bacteria or yeast. The system architecture has a partially automated bioprocessing system to concentrate biomass and purify recombinant protein. This system is designed to operate semi-autonomously with minimal crew intervention. The specific use-case scenario is to produce a thermal stable carbonic anhydrase to increase the efficiency of a proposed liquid amine CO 2 removal subsystem of an environmental control and life-support system (ECLSS) on Mars.

Biomanufacturing↗

NASA NTRSDate not supplied

Development of a Space Compatible Biomanufacturing System

Space biomanufacturing is a potential In Situ Resource Utilization (ISRU) strategy to provide critical consumables and products while minimizing the launched mass for long-duration, deep space missions. On Earth, the primary biological conversion of CO 2 to biomass is through photosynthesis, and sugars from photosynthetic organisms are used as feedstocks for microbial biomanufacturing. The efficiency of non-biological reduction of CO 2 to organic molecules, such as acetate or ethanol, has greatly increased in recent years. We are designing a biomanufacturing system to rely on electrochemical CO 2 conversion products for carbon substrates to support microbial growth and production of recombinant proteins. The preliminary design includes a gas-permeable membrane bioreactor with dry salts that are rehydrated and mixed with the carbon source to support growth of bacteria or yeast. The system architecture has a partially automated bioprocessing system to concentrate biomass and purify recombinant protein. This system is designed to operate semi-autonomously with minimal crew intervention. The specific use-case scenario is to produce a thermal stable carbonic anhydrase to increase the efficiency of a proposed liquid amine CO 2 removal subsystem of an environmental control and life-support system (ECLSS) on Mars.

Recombinant↗

NASA NTRS2023

Development of an Efficient Alternative to Recovery O2 From Metabolic CO2 Via Electrolysis Operated at Ambient Temperature and Driven By A Highly Selective Catalysis

The current State of Art (SOA) on oxygen recovery onboard the Environmental Control and Life Support System (ECLSS) at the International Space Station (ISS) is complex, heavy, and power consuming system that recovers approximately 50% of the oxygen (O 2 ) from metabolic carbon dioxide (CO 2 ). For future long duration beyond low earth orbit missions (LEO), O 2 recovery systems will need to be highly reliable, efficient, and recover a minimum of 75% O 2 from metabolic CO 2 . An alternative technology development effort currently underway at NASA Marshall Space Flight Center (MSFC) has the potential to significantly increase O 2 recovery currently limited to 50% (Sabatier) and reduce the complexity of ECLSS O 2 recovery. MSFC and University of Texas in Arlington (UTA) have jointly designed and fabricated a microfluid electrochemical reactor (MFECR) that operates at ambient conditions and utilizes a proprietary catalysis highly selective on reducing CO 2 to ethylene (C 2 H 4 ) at the cathode while O 2 is generated at the anode. The MFECR would replace three pieces of hardware for future ECLSS architectures: the current CO 2 Reduction Assembly (CRA) (Sabatier reactor), the Plasma Pyrolysis Assembly (PPA), and the Oxygen Generation Assembly (OGA). It is designed to interface directly with the CO 2 Removal Assembly (CDRA) and the Water Processing Assembly (WPA) to supply CO 2 reactant and water replenish respectively. This is expected to substantially improve sustainability of the ISS ECLSS and reduce requirement on power and weight. Here, we discuss the current development and evaluation efforts on different alternatives on not only the configuration and setup of the MFECR at an Engineering Design Unit (EDU) scale but also the selection of component materials.

Jesus A Dominguez↗

NASA NTRS1982

An electrochemical study of Ni/2+/, Co/2+/, and Zn/2+/ ions in melts of composition CaMgSi2O6

Results are reported for a study of the behavior of Ni(2+), Co(2+), and Zn(2+) in molten diopside, determined by cyclic voltametry, as a first step in adapting electrochemical methods for use in experimental geochemistry. The techniques used are described, the theory is briefly discussed, and it is demonstrated that Ni(2+), Co(2+), and Zn(2+) can be reduced, then reoxidized in an uncomplicated case of reversible charge transfer at the Pt electrode. This implies that the neutral metal atoms remain undissolved in the melt. The kinetics of the reduction process, the effects of concentration, the standard reduction potentials, and the diffusion coefficients are discussed in detail. The observations are consistent with the mechanism of Ni(2+) diffusion by transport from site to site. As the proportion of SiO2 in the melt increases, a higher activation energy is required for Ni(2+) to move, and the rate of diffusion is lowered.

Semkow, K. W.↗

NASA NTRS2016

Solar Powered CO.Sub.2 Conversion

Methods and devices for reducing CO.sub.2 to produce hydrocarbons are disclosed. A device comprises a photoanode capable of splitting H.sub.2O into electrons, protons, and oxygen; an electrochemical cell cathode comprising an electro-catalyst capable of reducing CO.sub.2; H.sub.2O in contact with the surface of the photoanode; CO.sub.2 in contact with the surface of the cathode; and a proton-conducting medium positioned between the photoanode and the cathode. Electrical charges associated with the protons and the electrons move from the photoanode to the cathode, driven in part by a chemical potential difference sufficient to drive the electrochemical reduction of CO.sub.2 at the cathode. A light beam is the sole source of energy used to drive chemical reactions. The photoanode can comprise TiO.sub.2 nanowires or nanotubes, and can also include WO.sub.3 nanowires or nanotubes, quantum dots of CdS or PbS, and Ag or Au nanostructures. The cathode can comprise a conductive gas diffusion layer with nanostructures of an electro-catalyst such as Cu or Co.

Chen, Bin↗