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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 OSTI2022

Carbon Anode Material from Biomass Pyrolysis Oil

Lithium-ion batteries (LIB) are an important component of electric vehicles and sodium-ion batteries (SIB) are an attractive alternative for grid electric storage. We are investigating a novel approach to synthesizing the carbon anode materials for these batteries from biomass pyrolysis oil as part of conversion processes to produce biofuels. Graphite is used as anode material in LIB and is exclusively produced from petroleum residue or mined mineral carbon. We have synthesized drop-in graphite by coking the heavy residual oil from the distillation of catalytic fast pyrolysis oil and by catalytic graphitizing raw pyrolysis oil. XRD and Raman spectroscopies were used to verify the production of high purity crystalline graphite. Figure 1 shows typical XRD spectra of the bio-graphite compared to commercial material as well as the charge/discharge cycle. Graphite particle sizes and morphologies were adjusted to improve performance using jet milling and carbon coating. The bio-graphite delivered a high capacity (335 mAh/g) when tested in a graphite half-cell. Full cell coin cell experiments were also conducted to verify the observations from half-cell testing. The high value of graphite (>$9/kg) can positively impact the economics of biofuels production and can be an important part of a future circular carbon economy. We have also investigated synthesizing hard carbon from pyrolysis oil for use as anode material in SIB. These batteries are not commercially mature but have great promise in grid storage and use earth abundant elements. We have demonstrated that pyrolysis oil can be used to synthesize hard carbon, which was subsequently be used in SIB experiments. This material achieved a sodium-ion capacity of 250 mAh/g and a first cycle efficiency of 78%, with opportunities to further optimize this performance from optimizing the composition of the pyrolysis oil to shaping the hard carbon particles. As with graphite, hard carbon is a high value (> $10/kg) material that could facilitate biofuels production.

BIOMASS FUELS,INORGANIC, ORGANIC, PHYSICAL, AND AN↗
DOE OSTI2020

Corn stover harvest reduces soil CO 2 fluxes but increases overall C losses

Abstract Harvesting corn ( Zea mays L.) stover for use as bioenergy feedstock may provide short‐term economic benefits and perhaps improve grain yield in continuous corn systems, but excessive stover removal may lead to long‐term depletion of soil C stocks. To better quantify the impacts of stover harvest on the soil C balance, we investigated CO 2 fluxes under three harvest treatments (none, moderate, and high) in three continuous corn systems: (a) no tillage and no biochar applications, (b) chisel plowing with biochar amendments, and (c) chisel plowing without biochar amendments were quantified. We sampled static chambers 14, 13, and 15 times in 2010, 2011, and 2012, respectively, and the measurements were used to calibrate the Agricultural Production Systems sIMulator model. Although CO 2 ‐C emissions did not differ among the three systems, both moderate (approximately 30%) and high (approximately 60%) stover removal rates reduced simulated CO 2 ‐C emissions by nearly 10% and more than 22%, respectively. Despite these reductions in CO 2 flux, the sum of CO 2 ‐C and stover C exceeded CO 2 ‐C losses in those plots without stover removal. This finding suggested soil C depletion was occurring for the soil and crop management practices used, even though depletion was not evident after 3 years. Application of biochar increased soil C levels, suggesting it may be able to offset some C losses. We conclude that for sustainable, highly productive agroecosystems that include stover harvest, all agronomic practices must be optimized to minimize C losses and maintain soil quality.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1978

Axial residual stresses in boron fibers

The axial residual stress distribution as a function of radius was determined from the fiber surface to the core including the average residual stress in the core. Such measurements on boron on tungsten (B/W) fibers show that the residual stresses for 102, 142, 203, and 366 micron diameter fibers were similar, being compressive at the surface and changing monotonically to a region of tensile within the boron. At approximately 25 percent of the original radius, the stress reaches a maximum tensile stress of about 860 mn/sq.m and then decreases to a compressive stress near the tungsten boride core. Data were presented for 203 micron diameter B/W fibers that show annealing above 900 C reduces the residual stresses. A comparison between 102 micron diameter B/W and boron on carbon (b/C) shows that the residual stresses were similar in the outer regions of the fibers, but that large differences near and in the core were observed. The effects of these residual stresses on the fracture of boron fibers were discussed.

Behrendt, D. R.↗
NASA NTRS1978

Axial residual stresses in boron fibers

A method of measuring axial residual stresses in boron fibers is presented. With this method, the axial residual stress distribution as a function of radius is determined from the fiber surface to the core including the average residual stress in the core. Such measurements on boron on tungsten (B/W) fibers show that the residual stresses for 102, 142, 203, and 366 micron diam fibers are similar, being compressive at the surface and changing monotonically to a region of tensile stress within the boron. At approximately 25% of the original radius, the stress reaches a maximum tensile stress of about 860 MN sq m and then decreases to a compressive stress near the tungsten boride core. Data are presented for 203-micron diam B/W fibers that show annealing above 900 C reduces the residual stresses. A comparison between 102-micron diam B/W and boron on carbon (B/C) show that the residual stresses are similar in the outer regions of the fibers, but that large differences near and in the core are observed. Fracture of boron fibers is discussed.

Behrendt, D. R.↗
NASA NTRS1993

Removal of carbonaceous contaminants from silica aerogel

Capture of micrometeorite material from low Earth orbit or dust grains around active comets for return to terrestrial laboratories, capable of practicing the most up to date techniques of chemical isotopic and mineralogical analysis, will greatly enhance our knowledge of primitive material in the solar system. The next generation of space launched cosmic dust collectors will undoubtedly include extremely low density target materials such as silica aerogel as the decelerating and arresting medium. This material has been found to be clean from the point of view of inorganic elements and is thus acceptable for the purpose of harvesting grains to be studied by, for example PIXE, INAA, or SXRF. However, the process used in making aerogel leaves substantial carbon and hydrogen containing residues which would negate their suitability for collection and subsequent investigation of the very important CHON particles. Attempts to precondition aerogel by solvent extraction or heating at 500 C and 750 C in air for 24 hours or under a vacuum of 2(7)(exp -7) torr at 260 C were largely ineffective except that pyrolysis did reduce volatile species. In this investigation we have examined the use of supercritical fluids for the purpose of extracting organic residues. The logic of the new approach is that beyond the supercritical point a substance has the solvating properties of a liquid but the viscosity characteristics of a gas. For example carbon dioxide becomes supercritical at a pressure of 73 atmospheres and a temperature of 31 C; in consequence it can transform to a very powerful and ultraclean solvent. It can dissolve organic matter from low molecular weight up to molecules containing 90 carbon atoms. On release of pressure the fluid reverts to a gas which can easily be pumped away and removed from the substrate being extracted.

Huang, Hui-Ping↗
DOE OSTI2021

BETO 2021 Peer Review - CAP Process Research

Combined Algal Processing (CAP) is an algae biorefining approach that employs pretreatment and extraction operations to fractionate algal biomass into an organic liquid phase containing lipids, an aqueous hydrolysate phase containing carbohydrates and protein, and a residual solid phase containing insoluble matter. Each of these fractions is upgraded to fuels and/or co-products, including non-isocyanate polyurethanes from unsaturated lipids, fuels from saturated lipids, fuel precursor carboxylic acids from the hydrolysate, and conductive carbons from the solid residue. Techno-economic analysis of multiple CAP configurations suggests that some configurations have a viable pathway to algal biofuels at $2.50/gallon of gasoline equivalent.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2023

Recent development and manufacturing of coal-derived building materials

Coal has been challenged because coal combustion generates large quantities of carbon dioxide (CO2), which contributes to global warming. Pyrolysis char (PC), a valuable byproduct of coal that does not liberate CO2 when produced in an inert environment, can be used as a high carbon content fuel in combustion and gasification. However, using PC as a fuel is not an eco-friendly and cost-efficient way to make energy. Contrastingly using PC to make engineered products does offer an eco-friendly, attractive and value-added use. This paper introduces a novel integrated coal pyrolysis and solvent extraction process invented by the University of Wyoming (UW) to convert as-mined coal from the Powder River Basin Coal Field, Wyoming, to functional carbon products, which together liberates very little CO2. PC and coal deposit, extract and residual (CDER) are two functional carbon products that can be used in the development and manufacture of high value coal-derived building materials. The novel development of three building products known as coal-derived char bricks (CCB), carbon structural unit (CSU), and char-based insulation foam (CIF) are introduced. The approaches to manufacture them are investigated, including consideration of the eco-friendly approaches, optimization of engineering performance, and cost effectiveness relative to traditional products. CCBs show advantages in terms of their light weight (< 1 g/cm3) and good compressive strength (> 14 MPa). CSUs possess high compressive strength (> 30 MPa) and low thermal conductivity (< 0.3 W/mK), while CIFs can achieve a low thermal conductivity of 0.06 W/mK. Two demonstration houses have been built on UW campus, one using CCBs and another using commercial clay bricks. The performances of these houses are being monitored for temperature control, humidity uptake, noise reduction, inside air volatile organic content, indoor air quality and weatherability. The performance of the CCBs in terms of these criteria is discussed.

Ng, Kam↗
NASA NTRS1977

Residual stresses in boron/tungsten and boron/carbon fibers

Longitudinal residual stress distribution is determined for 102-micron diam B/W and B/C fibers. The 102-micron diam B/W fibers are deposited on a 12.7-micron diam tungsten wire resistively heated in a BCl3-H2 reactor. The 102-micron diam B/C fibers are made by deposition of boron on a pyrolytic graphite-coated carbon fiber. The longitudinal residual stress distribution is calculated from measurements of the change in length of the fiber produced by removal of the surface through electropolishing. It is found that for both types of fibers, the residual stress vary from a compressive stress at the surface to a tensile stress in the boron near the core. Closer to the core and in the core, significant differences in the residual stresses are observed for the B/W and B/C fibers.

Behrendt, D. R.↗
DOE OSTI2025

Soil erosion and lateral carbon fluxes from corn stover-derived biofuel

Abstract Crop residues hold promise to alleviate food vs. fuel competition and contribute to biofuel production. However, the impacts of lateral sediment and carbon fluxes caused by residue removal are not fully understood. Here we employ agroecosystem modeling to conservatively estimate lateral sediment and carbon fluxes resulting from partial corn stover removal in the U.S. Midwest. Results show substantial increases in soil erosion resulting from corn stover removal. For example, the area of continuous corn and corn soybean cropping systems exceeding soil erosion tolerance threshold could increase from 1.1 to 13.3% because of 66% corn stover removal. Depending on removal intensity, conservation, and crop rotation, the stover removal-induced increases in eroded soil organic carbon is equivalent to 3.9–12.5 gCO 2 e MJ −1 , which is comparable to other components of the life cycle impacts of corn stover-derived biofuel. Our findings highlight the need to consider the soil erosion and lateral carbon fluxes impacts of corn stover removal in designing supply chains for cellulosic biofuel production.

Science & Technology - Other Topics↗
NASA NTRS1983

Samarium-146 in the early solar system - Evidence from neodymiun in the Allende meteorite

A carbon-chromite fraction from the Allende C3V chondrite shows strikingly large isotopic enrichments of neodymium-142 (0.47 percent) and neodymium-143 (36 percent). Both apparently formed by alpha decay of samarium-146 and samarium-147 (half-lives 1.03 x 10 to the 8th and 1.06 x 10 to the 11th years), but the isotopic enrichment was greatly magnified by recoil of residual nuclei into a carbon film surounding the samarium-bearing grains. These data provide an improved estimate of the original abundance of extinct samarium-146 in the early solar system, Sm-146/Sm-144 = (4.5 + or - 0.5) x 10 to the -3rd, higher than predicted by some models of p-process nucleosynthesis. It may be possible to use this isotopic pair as a chronometer of the early solar system.

Lugmair, G. W.↗
DOE OSTI2021

A comparative study of two-way and offline coupled WRF v3.4 and CMAQ v5.0.2 over the contiguous US: performance evaluation and impacts of chemistry–meteorology feedbacks on air quality

The two-way coupled Weather Research and Forecasting and Community Multiscale Air Quality (WRF-CMAQ) model has been developed to more realistically represent the atmosphere by accounting for complex chemistry–meteorology feedbacks. In this study, we present a comparative analysis of two-way (with consideration of both aerosol direct and indirect effects) and offline coupled WRF v3.4 and CMAQ v5.0.2 over the contiguous US. Long-term (5 years from 2008 to 2012) simulations using WRF-CMAQ with both offline and two-way coupling modes are carried out with anthropogenic emissions based on multiple years of the U.S. National Emission Inventory and chemical initial and boundary conditions derived from an advanced Earth system model (i.e., a modified version of the Community Earth System Model/Community Atmospheric Model). The comprehensive model evaluations show that both two-way WRF-CMAQ and WRF-only simulations perform well for major meteorological variables such as temperature at 2 m, relative humidity at 2 m, wind speed at 10 m, precipitation (except for against the National Climatic Data Center data), and shortwave and longwave radiation. Both two-way and offline CMAQ also show good performance for ozone (O3) and fine particulate matter (PM 2.5 ). Due to the consideration of aerosol direct and indirect effects, two-way WRF-CMAQ shows improved performance over offline coupled WRF and CMAQ in terms of spatiotemporal distributions and statistics, especially for radiation, cloud forcing, O 3 , sulfate, nitrate, ammonium, elemental carbon, tropospheric O 3 residual, and column nitrogen dioxide (NO 2 ). For example, the mean biases have been reduced by more than 10 W m –2 for shortwave radiation and cloud radiative forcing and by more than 2 ppb for max 8 h O 3 . However, relatively large biases still exist for cloud predictions, some PM 2.5 species, and PM 10 that warrant follow-up studies to better understand those issues. The impacts of chemistry–meteorological feedbacks are found to play important roles in affecting regional air quality in the US by reducing domain-average concentrations of carbon monoxide (CO), O 3 , nitrogen oxide (NO x ), volatile organic compounds (VOCs), and PM 2.5 by 3.1 % (up to 27.8 %), 4.2 % (up to 16.2 %), 6.6 % (up to 50.9 %), 5.8 % (up to 46.6 %), and 8.6 % (up to 49.1 %), respectively, mainly due to reduced radiation, temperature, and wind speed. The overall performance of the two-way coupled WRF-CMAQ model achieved in this work is generally good or satisfactory and the improved performance for two-way coupled WRF-CMAQ should be considered along with other factors in developing future model applications to inform policy making.

58 GEOSCIENCES↗
DOE OSTI2026

Trends and limits of CO 2 capture in solid and liquid sorbents at standard conditions

Carbon capture and storage (CCS) plays a critical role in achieving climate change mitigation targets, offering a pathway to decarbonize power generation, industrial processes, and heat production while addressing atmospheric CO 2 removal. While CCS technologies are technically advanced, the widespread adoption of 100 % CO 2 capture capacities such as 1 mol of CO 2 /mol of material and 1 g CO 2 /g storage (targeted by the DARPA, Defense Sciences Office, USA Govt.) has raised questions about the feasibility of achieving higher capture capacities. In the context of limiting global warming to 1.5°C, reaching 100 % CO 2 capture capacity is increasingly necessary, with residual emissions requiring complementary carbon dioxide removal (CDR) technologies. This review exclusively focuses on the CO 2 capture capacities of various sorbents under standard conditions, using different evaluation metrics. This study explores the performance of solid and liquid sorbents under standard conditions, analyzing factors including surface area, pore structure, solvent type, and functionalization to identify materials optimized for industrial-scale CCS applications. Emerging sorbents, including ILs, MOFs, COFs, POPs, DES, RCC, hybrid materials, and reactive sorbents, offer significant potential for enhanced selectivity and energy-efficient regeneration. Through a systematic assessment of gravimetric, volumetric, and molar capacities, the study provides insights into material efficiencies and trade-offs, offering guidance on optimizing sorbent selection for specific applications. The research advances understanding of scalable CCS technologies, contributing to global efforts to achieve net-zero emissions and address the pressing challenge of climate change.

Absorption↗
NASA NTRS2016

Performance of Silica Gel in the Role of Residual Air Drying. Part II.

Removal of carbon dioxide (CO2) is a necessary step in air revitalization and is often accomplished with sorbent materials. Since moisture competes with CO2 in zeolite sorbent materials, it is necessary to remove the water first. This is typically accomplished in two stages: “bulk” removal and “residual” drying. Silica gel is used as the bulk drying material in the Carbon Dioxide Removal Assembly (CDRA) in operation on the ISS (International Space Station). There has been some speculation that silica gel may also be capable of serving as both bulk and residual drying material to reduce system mass and Foreign Object Debris (FOD). Previous research tested silica gel alone as drying material. However, the silica gel volume used was not comparable to the current amount used on the CDRA. Therefore, the tests were repeated with the new silica gel volume. This paper discusses the fabrication and assembly of the modified canister to accommodate the new volume, the testing, and the evaluation of the test results.

Air Revitalization↗
NASA NTRS1986

Noble gases in the diamond-free ureilite, ALHA 78019 - The roles of shock and nebular processes

The noble gases for unshocked ureilite ALHA 78019 and moderately shocked ureilite Kenna are measured. The preparation of the samples and the analysis procedures are described. The analyses reveal that for ALHA 78019 the residue yield equals 2.5 percent of the original mass of the meteorite and 25 percent of the gas is contained in the fine-grained amorphous carbon, and for Kenna the residue yield equals 2.9 percent and 60 percent of the noble gas is contained in the carbon. It is noted that the gases and carbon are present in the ureilites prior ot the shock that produced the diamond, and the shock has no effect on the origin of the carbon in these meteorites. The source of the gas-rich carbon in the ureilite ALHA 78019 is investigated; the Xe-130/C ratio, which equals 4.2 x 10 to the -10th, implies that the gases were acquired while the ureilite was exposed to the solar nebula.

Wacker, J. F.↗
DOE OSTI2022

Detailed modeling of hydrogen release and particle shrinkage during pyrolysis of inhomogeneous wood

Hydrogen release during pyrolysis of woody biomass is studied considering anisotropicity and inhomogeneity of wood structure. A new anisotropic shrinkage model is proposed based on the decomposition of main wood constituents, i.e., cellulose, hemicellulose, and lignin. The new shrinkage model can predict the temporal evolution of the wood structure, and the differences between axial and radial shrinkage during pyrolysis. The model agrees very well with several experimental data from the literature. Based on particle temperature during conversion, the pyrolysis is partitioned into four stages, and the hydrogen release and H 2 formation from each stage are investigated. Stage (IV) of pyrolysis, from 1000 to 1273 K, is found to be efficient for H 2 production owing to the production of considerable mass of H with a minimal amount of tar species. Furthermore, the char quality is found to be different at the end of stages (II), (III), and (IV), where around 67.7, 80.5, and 93.4% wt. of solid residue is made of carbon, respectively. The model is also used to explain how the heating rate affects the temperature distribution inside the particle and how it shifts the peak of hydrogen release. Finally, the pyrolysis of two inhomogeneous wood samples — a beech twig with bark and a beech dowel with growth rings — are investigated. The bark can affect the pyrolysis rate, products, and flow pattern inside the particle. The growth rings do not have a considerable effect on the pyrolysis rate and products, but they have a significant impact on the flow pattern. This has an important implication for char conversion studies where the internal surface area and porosity field distribution have a significant effect on the gasification and oxidation rates.

09 BIOMASS FUELS↗
DOE OSTI2024

Abstract for CRADA between National Energy Technology Laboratory and Carbon To Stone, Inc.

The National Energy Technology Laboratory (NETL) and Carbon To Stone (CTS), Inc. (Participant) will collaborate on a techno-economic assessment (TEA) and life cycle assessment (LCA) of CTS’s carbon dioxide removal (CDR) technology under an awarded project from the Department of Energy’s Direct Air Capture Pre-Commercialization Technology Prize. CTS has developed a technological platform that captures carbon dioxide (CO2) from air and mineralizes it into durable carbonates using alkaline industrial residues such as steel slag and mine tailings. In addition, CTS’s technology uses electrochemistry to recover value-added energy critical metals (ECMs) from these residues. NETL has expertise in CDR TEA and LCA development. The collaboration between CTS and NETL aims to quantify the performance, cost and lifecycle impacts of CTS’s technology and produce LCA and TEA models that can accelerate development and deployment of this technology.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2024

Hydrogen and Power Co-Production Using Direct sCO 2 Power Cycles

This report presents the techno-economic analysis (TEA) results of integrating a modified autothermal reforming (ATR) hydrogen (H 2 ) production plant with a natural gas-fired, utility-scale power plant based on the direct supercritical carbon dioxide (sCO 2 ) power cycle. In this study, the H 2 production and the power plant are fully integrated in terms of heat, fuel, and carbon capture and storage (CCS). The ATR process has significant waste heat available for heat integration with a direct-fired sCO 2 power plant that benefits the power plant efficiency. The off-gas stream from the modified ATR process is primarily carbon dioxide (CO 2 ), carbon monoxide (CO), and residual H 2 . As supplemental fuel, it has beneficial heating value in the CO and H 2 that can be used in the direct sCO 2 power cycle. Finally, the direct sCO 2 power plant can isolate the CO 2 produced at the facility for CCS.

08 HYDROGEN↗
DOE OSTI2024

Carbon Ore-Derived Critical Materials for Clean Energy Technologies

Conference presentation at American Institute of Chemical Engineers (AIChE) Annual Meeting, San Diego, California, October 27–31, 2024. Trends in the manufacture of electric vehicles that use graphite-based LIBs are rising steeply in the United States and globally, but the U.S. domestic supply chains for graphite, the largest component in an LIB by mass, is severely limited and faces complicated geopolitical dynamics with foreign sources. Consequently, the United States has designated graphite as a critical mineral to focus attention and resources to develop technologies to meet the challenge of limited domestic graphite supply chains. Results obtained so far based on the UCOP process have successfully validated the technology at the laboratory scale, with the produced graphite material showing up to 95% degree of graphitization, high carbon purity of ~99.98%, residual ash content of ≤0.02%, negligible moisture, low trace elements, and high electrochemical stability. These results suggest that the emerging UCOP technology is a promising approach to effectively synthesize high-quality graphite from abundant coal and coal waste resources in the United States to create a sustainable domestic critical graphite supply chain. A brief description of the status of UCOP process development and representative results will be presented.

01 COAL, LIGNITE, AND PEAT↗