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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 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Synthesis of perfluoroalkylene dianilines

The objective of this contrast was to optimize and scale-up the synthesis of 2,2-bis(4-aminophenyl)-hexafluoropropane and 1,3-bis(4-aminophenyl)hexafluoropropane, as well as to explore avenues to other perfluoroalkyl-bridged dianilines. Routes other than Friedel-Crafts reaction leading to 2,2-bis(4-aminophenyl)hexafluoropropane were investigated. The processes utilizing bisphenol-AF were all unsuccessful; reactions aimed at the production of 4-(hexafluoro-2-halo-isopropyl)aniline from the hydroxyl intermediate failed to yield the desired products. Tailoring the conditions of the Friedel-Crafts reaction of 4-(hexafluoro-2-hydroxyisopropyl)aniline, aniline, and aluminum chloride by using hydrochloride salts and selecting optimum reagent ratios, reaction times, and temperature resulted in approx. 20% yield of pure crystallized 2,2-bis(4-aminophenyl)hexafluoropropane in 0.2 mole reaction batches. Yields up to approx. 40% were realized in small, approx. 0.01 mole, batches. The synthesis of 1,3-bis(4-aminophenyl)hexafluoropropane starting with perfluoroglutarimidine was reinvestigated. The yield of the 4-step reaction sequence giving 1,3-bis(4-acetamidophenyl)hexafluoropropane was raised to 44%. The yield of the subsequent hydrolysis process was improved by a factor of approx. 2. Approaches to prepare other perfluoroalkyl-bridged dianilines were unsuccessful. Reactions reported to proceed readily with trifluoromethyl substituents failed when longer chain perfluoroalkyl groups were employed.

Paciorek, K. L.↗
DOE OSTI2019

Enhanced Light Extraction from Low Cost White OLEDs Fabricated on Novel Patterned Substrates” (Final Report)

Organic LEDs (OLEDs) are a very attractive emerging solid state lighting (SSL) technology. Currently, one of the main challenges is to increase the extraction of the light generated inside the OLED into the forward (viewing) hemisphere. In conventional OLEDs fabricated on a transparent flat anode coated on glass the outcoupling factor is only about 20%. About 50% of the light is lost at the metal cathode (surface plasmon excitation), and waveguided internally in the organic layers and the transparent anode. Another ~30% is waveguided in the substrate to its edges. The research addressed this issue of outcoupling by evaluating OLEDs fabricated on corrugated plastic substrates manufactured in a cost-effective approach. It demonstrated that the outcoupling from such OLEDs can exceed 50% by mitigating plasmon–related loss and internal waveguiding, even without the addition of a microlens array or a hemispherical lens, either of which extracts the light trapped in the substrate. Simulations conducted in parallel with the experimental effort demonstrated how the corrugation assists in the outcoupling. The project also evaluated the role of the corrugation pitch and height in determining the outcoupling factor and other properties of the OLEDs. The technical effectiveness and economic feasibility of the project lie in the patterning of the extracting plastic substrates in an approach that is scalable to roll-to-roll (R2R) manufacturing. R2R processes are drastically lower-cost than batch or single-unit fabrication. The corrugated plastic substrates studied are part of an integrated substrate that includes also a microlens array at the air-side of the substrate and a conductive electrode. The project that was a university-industry collaboration is of major benefit to the public as it demonstrates the feasibility of manufacturing highly efficient OLEDs for SSL in a R2R process, which would drastically reduce the manufacturing cost and increase production in the USA. SSL is efficient and environmentally-friendly. It reduces electricity consumption, and hence lighting cost.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
NASA NTRS2001

Maximally Informative Statistics for Localization and Mapping

This paper presents an algorithm for localization and mapping for a mobile robot using monocular vision and odometry as its means of sensing. The approach uses the Variable State Dimension filtering (VSDF) framework to combine aspects of Extended Kalman filtering and nonlinear batch optimization. This paper describes two primary improvements to the VSDF. The first is to use an interpolation scheme based on Gaussian quadrature to linearize measurements rather than relying on analytic Jacobians. The second is to replace the inverse covariance matrix in the VSDF with its Cholesky factor to improve the computational complexity. Results of applying the filter to the problem of localization and mapping with omnidirectional vision are presented.

Deans, Matthew C.↗
DOE OSTI2019

Scalable One‐Step Gel Conversion Route to High‐Performance CHA Zeolite Hollow Fiber Membranes and Modules for CO 2 Separation

Efficient separation of CO 2 from other molecules such as CH 4 , N 2 , and hydrocarbons is a key problem in many energy production and greenhouse gas reduction schemes. Zeolite materials demonstrate attractive gas separation properties, but their industrial application as membranes in gas separation are elusive because of high cost and low reproducibility of conventional fabrication techniques. A facile method is demonstrated for the fabrication of high‐silica CHA zeolite membranes on low‐cost alumina hollow fiber substrates by a one‐step direct gel conversion method, along with a detailed characterization of the CHA hollow fiber membranes. To demonstrate the scalability of the method, 20 hollow fiber (710 μm OD and 390 μm ID) membranes are synthesized in the same batch and assembled into a module. Under dry conditions, the membranes show an excellent CO 2 permeance up to 3500 GPU (1 Gas Permeation Unit = 3.348 × 10 −10 mol m −2 s −1 Pa −1 ) and an excellent CO 2 separation performance (e.g., CO 2 /CH 4 separation factors up to 210 in the 1–7 bar feed pressure range). In addition, the membranes exhibit a considerable increase in CO 2 selectivity under humid (saturated water vapor) conditions with moderate permeance drops. This study opens a promising new path for accelerated development of low‐cost zeolitic membranes for gas separation technology.

Yang, Shaowei↗
NASA NTRS1998

Characterizing the Hazard of a Wake Vortex Encounter

The National Aeronautics and Space Administration (NASA) is conducting research with the goal of enabling safe improvements in the capacity of the nation's air transportation system. The wake vortex upset hazard is an important factor in establishing the minimum safe spacing between aircraft during landing and take-off operations, thus impacting airport capacity. Static and free-flight wind tunnel tests and flight tests have provided an extensive data set for improved understanding of vortex encounter dynamics and simulation. Piloted and batch simulation studies are also ongoing to establish a first-order hazard metric and determine the limits of an operationally acceptable wake induced upset. This paper outlines NASA's research in these areas.

Vicroy, Dan D.↗
DOE OSTI2016

Fuel Cycle Performance of Thermal Spectrum Small Modular Reactors

Small modular reactors may offer potential benefits, such as enhanced operational flexibility. However, it is vital to understand the holistic impact of small modular reactors on the nuclear fuel cycle and fuel cycle performance. The focus of this paper is on the fuel cycle impacts of light water small modular reactors in a once-through fuel cycle with low-enriched uranium fuel. A key objective of this paper is to describe preliminary reactor core physics and fuel cycle analyses conducted in support of the U.S. Department of Energy Office of Nuclear Energy Fuel Cycle Options Campaign. Challenges with small modular reactors include: increased neutron leakage, fewer assemblies in the core (and therefore fewer degrees of freedom in the core design), complex enrichment and burnable absorber loadings, full power operation with inserted control rods, the potential for frequent load-following operation, and shortened core height. Each of these will impact the achievable discharge burn-up in the reactor and the fuel cycle performance. This paper summarizes the results of an expert elicitation focused on developing a list of the factors relevant to small modular reactor fuel, core, and operation that will impact fuel cycle performance. Preliminary scoping analyses were performed using a regulatory-grade reactor core simulator. The hypothetical light water small modular reactor considered in these preliminary scoping studies is a cartridge type one-batch core with 4.9% enrichment. Some core parameters, such as the size of the reactor and general assembly layout, are similar to an example small modular reactor concept from industry. The high-level issues identified and preliminary scoping calculations in this paper are intended to inform on potential fuel cycle impacts of one-batch thermal spectrum SMRs. In particular, this paper highlights the impact of increased neutron leakage and reduced number of batches on the achievable burn-up of the reactor. Fuel cycle performance metrics for a small modular reactor are compared to a conventional three-batch light water reactor in the following areas: nuclear waste management, environmental impact, and resource utilization. Metrics performance for a small modular reactor are degraded for mass of spent nuclear fuel and high level waste disposed, mass of depleted uranium disposed, land use per energy generated, and carbon emission per energy generated

Worrall, Andrew↗
DOE OSTI2020

Analysis of the sludge batch 9 (Macrobatch 10) DWPF pour stream glass sample

A pour stream (PS) sample taken during processing of Sludge Batch 8 (SB8, Macrobatch 10) was analyzed by Savannah River National Laboratory (SRNL) to verify compliance with the Defense Waste Processing Facility (DWPF) Glass Product Control Program. The following conclusions were drawn from these analyses; The sum of oxides for the SB8 PS glass (97.41 wt%) is within the Product Composition Control System (PCCS) limits (100 ± 5 wt%); The average Waste Dilution Factor (WDF) calculated from the Tank 40 dried sludge analysis results for SB8 is 1.9 ± 0.1. In general, the radionuclide concentration of the SB8 PS glass sample calculated using this WDF is in good agreement with the measured radionuclide content; The Product Consistency Test (PCT) results indicate that the SB8 PS glass meets the Waste Acceptance Product Specifications (WAPS) for durability, with normalized release rates for boron, lithium and sodium all at least two standard deviations lower than those of the Environmental Assessment (EA) glass; The average measured density of the SB8 PS glass is 2.72 g/cm 3 , consistent with previous PS samples; and, The average measured Fe 2+ /ΣFe ratio of the SB8 PS glass is 0.15, within the target range of 0.09- 0.33, and closely resembling the predicted REDOX value of 0.15.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Technetium immobilization by materials through sorption and redox-driven processes: A literature review

The purpose of this review is to evaluate materials for use as a barrier or other deployed technology to treat technetium-99 (Tc) in the subsurface. To achieve this, Tc interactions with different materials are considered within the context of remediation strategies. Several naturally occurring materials are considered for Tc immobilization, including iron oxides and low solubility sulfide phases. Synthetic materials are also considered, and include tin-based materials, sorbents (resins, activated carbon, modified clays), layered double hydroxides, metal organic frameworks, cationic polymeric networks and aerogels. All of the materials were evaluated for their potential in-situ and ex-situ performance with respect to long-term Tc uptake and immobilization, environmental impacts and deployability. Other factors such as the technology maturity, cost and availability were also considered. Given the difficulty of evaluating materials under different experimental conditions (e.g., solution chemistry, redox conditions, solution to solid ratio, Tc concentration etc.), a subset of these materials will be selected, on the basis of this review, for subsequent standardized batch loading tests.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1983

Aerodynamic coefficient identification package dynamic data accuracy determinations: Lessons learned

The errors in the dynamic data output from the Aerodynamic Coefficient Identification Packages (ACIP) flown on Shuttle flights 1, 3, 4, and 5 were determined using the output from the Inertial Measurement Units (IMU). A weighted least-squares batch algorithm was empolyed. Using an averaging technique, signal detection was enhanced; this allowed improved calibration solutions. Global errors as large as 0.04 deg/sec for the ACIP gyros, 30 mg for linear accelerometers, and 0.5 deg/sec squared in the angular accelerometer channels were detected and removed with a combination is bias, scale factor, misalignment, and g-sensitive calibration constants. No attempt was made to minimize local ACIP dynamic data deviations representing sensed high-frequency vibration or instrument noise. Resulting 1sigma calibrated ACIP global accuracies were within 0.003 eg/sec, 1.0 mg, and 0.05 deg/sec squared for the gyros, linear accelerometers, and angular accelerometers, respectively.

Heck, M. L.↗
DOE OSTI2024

A graphics processing unit accelerated sparse direct solver and preconditioner with block low rank compression

We present the GPU implementation efforts and challenges of the sparse solver package STRUMPACK. The code is made publicly available on github with a permissive BSD license. STRUMPACK implements an approximate multifrontal solver, a sparse LU factorization which makes use of compression methods to accelerate time to solution and reduce memory usage. Multiple compression schemes based on rank-structured and hierarchical matrix approximations are supported, including hierarchically semi-separable, hierarchically off-diagonal butterfly, and block low rank. Here, in this paper, we present the GPU implementation of the block low rank (BLR) compression method within a multifrontal solver. Our GPU implementation relies on highly optimized vendor libraries such as cuBLAS and cuSOLVER for NVIDIA GPUs, rocBLAS and rocSOLVER for AMD GPUs and the Intel oneAPI Math Kernel Library (oneMKL) for Intel GPUs. Additionally, we rely on external open source libraries such as SLATE (Software for Linear Algebra Targeting Exascale), MAGMA (Matrix Algebra on GPU and Multi-core Architectures), and KBLAS (KAUST BLAS). SLATE is used as a GPU-capable ScaLAPACK replacement. From MAGMA we use variable sized batched dense linear algebra operations such as GEMM, TRSM and LU with partial pivoting. KBLAS provides efficient (batched) low rank matrix compression for NVIDIA GPUs using an adaptive randomized sampling scheme. The resulting sparse solver and preconditioner runs on NVIDIA, AMD and Intel GPUs. Interfaces are available from PETSc, Trilinos and MFEM, or the solver can be used directly in user code. We report results for a range of benchmark applications, using the Perlmutter system from NERSC, Frontier from ORNL, and Aurora from ALCF. For a high frequency wave equation on a regular mesh, using 32 Perlmutter compute nodes, the factorization phase of the exact GPU solver is about 6.5× faster compared to the CPU-only solver. The BLR-enabled GPU solver is about 13.8× faster than the CPU exact solver. For a collection of SuiteSparse matrices, the STRUMPACK exact factorization on a single GPU is on average 1.9× faster than NVIDIA’s cuDSS solver.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2016

Analytical results from routine DSSHT and SEHT monthly samples

Strip Effluent Hold Tank (SEHT) and Decontaminated Salt Solution Hold Tank (DSSHT) samples from several of the “microbatches” of Integrated Salt Disposition Project (ISDP) Salt Batch (“Macrobatch”) 8B have been analyzed for 238 Pu, 90 Sr, 137 Cs, cations (Inductively Coupled Plasma Emission Spectroscopy - ICPES), and anions (Ion Chromatography Anions - IC-A). The analytical results from the current microbatch samples are similar to those from previous macrobatch samples. The Cs removal continues to be excellent, with decontamination factors (DF) averaging 22,100 (114% RSD). The bulk chemistry of the DSSHT and SEHT samples does not show any signs of unusual behavior, other than lacking the anticipated degree of dilution that is calculated to occur during Modular Caustic-Side Solvent Extraction Unit (MCU) processing.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Analytical results from salt batch 9 routine DSSHT and SEHT monthly samples

Strip Effluent Hold Tank (SEHT) and Decontaminated Salt Solution Hold Tank (DSSHT) samples from several of the “microbatches” of Integrated Salt Disposition Project (ISDP) Salt Batch (“Macrobatch”) 9 have been analyzed for 238 Pu, 90 Sr, 137 Cs, cations (Inductively Coupled Plasma Emission Spectroscopy - ICPES), and anions (Ion Chromatography Anions - IC-A). The analytical results from the current microbatch samples are similar to those from previous macrobatch samples. The Cs removal continues to be acceptable, with decontamination factors (DF) averaging 25700 (107% RSD). The bulk chemistry of the DSSHT and SEHT samples do not show any signs of unusual behavior, other than lacking the anticipated degree of dilution that is calculated to occur during Modular Caustic-Side Solvent Extraction Unit (MCU) processing.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Rate of MgO Pickup in Alumina Inclusions in Aluminum-Killed Steel

This work aims to clarify the rate and mechanism of MgO pickup by alumina inclusions and the effect of oxide impurities in MgO crucibles on this transformation. Two MgO crucibles from different batches from the same supplier were used in laboratory experiments with Al-killed steel. A kinetic model was developed, based on mass-transfer control in the liquid steel. Rate constants were fitted using inclusion analysis. The rate of magnesium transfer from the two types of crucibles was found to differ by a factor of 20; faster magnesium transfer was associated with formation of a slag layer on the inner surface of the crucible wall (rather than a solid spinel product layer). The kinetic model was also used to simulate industrial scale ladle refining (1) to illustrate the effects of total oxygen concentration and (2) to evaluate the contribution of steel-refractory reaction (in addition to steel-slag reaction) on the rate of MgO pickup in alumina inclusion. The rate of MgO pickup was higher with a lower inclusion concentration. For ladle desulfurization, the extent of MgO pickup in inclusions is directly linked to the extent of desulfurization; both reactions are controlled by the oxygen potential at the steel-slag interface.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Assessing the impact of substrate-level enzyme regulations limiting ethanol titer in Clostridium thermocellum using a core kinetic model

Clostridium thermocellum is a promising candidate for consolidated bioprocessing because it can directly ferment cellulose to ethanol. Despite significant efforts, achieved yields and titers fall below industrially relevant targets. This implies that there still exist unknown enzymatic, regulatory, and/or possibly thermodynamic bottlenecks that can throttle back metabolic flow. By (i) elucidating internal metabolic fluxes in wild-type C. thermocellum grown on cellobiose via 13 C-metabolic flux analysis ( 13 C-MFA), (ii) parameterizing a core kinetic model, and (iii) subsequently deploying an ensemble-docking workflow for discovering substrate-level regulations, this paper aims to reveal some of these factors and expand our knowledgebase governing C. thermocellum metabolism. Generated 13 C labeling data were used with 13 C-MFA to generate a wild-type flux distribution for the metabolic network. Notably, flux elucidation through MFA alluded to serine generation via the mercaptopyruvate pathway. Using the elucidated flux distributions in conjunction with batch fermentation process yield data for various mutant strains, we constructed a kinetic model of C. thermocellum core metabolism (i.e. k-ctherm138). Subsequently, we used the parameterized kinetic model to explore the effect of removing substrate-level regulations on ethanol yield and titer. Upon exploring all possible simultaneous (up to four) regulation removals we identified combinations that lead to many-fold model predicted improvement in ethanol titer. In addition, by coupling a systematic method for identifying putative competitive inhibitory mechanisms using K-FIT kinetic parameterization with the ensemble-docking workflow, we flagged 67 putative substrate-level inhibition mechanisms across central carbon metabolism supported by both kinetic formalism and docking analysis.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2019

Cesium Ion Exchange Testing Using a Three-Column System with Crystalline Silicotitanate and Hanford Tank Waste 241-AP-107

Washington River Protection Solutions (WRPS) is working to support early production of immobilized low-activity waste by feeding Hanford tank supernate from tank farms to the Hanford Waste Treatment and Immobilization Plant (WTP) Low-Activity Waste (LAW) facility. This goal incorporates the design of a Tank-Side Cesium Removal (TSCR) system, which in effect filters tank waste supernate and processes it through a cesium ion exchange medium to remove 137Cs. The 137Cs-depleted product is sent to the WTP for vitrification. Rovira et al. (2018) reported the successful Cs removal from Hanford tank 241-AP-107 waste (hereafter called AP-107) using crystalline silicotitanate (CST) ion exchange media manufactured by Honeywell UOP, LLC (product IONSIVTM R9140-B, Batch 2081000057) in a lead-lag column system. Since that testing, WRPS has changed the column design to a three-column system. WRPS requested a repeated study with AP-107 tank waste using a different batch of IONSIVTM R9140-B, Lot 2002009604, in a three-column format. A small-scale test platform was constructed to demonstrate solids filtration, Cs removal, and LAW vitrification and installed at Pacific Northwest National Laboratory. This report describes the small-scale ion exchange testing system component of the test platform and the processing of approximately 8.55 L of filtered AP-107 supernate using CST, Lot 8056262-999, that passed through a 25-mesh filter. This report also describes the Cs ion exchange batch contact testing to determine the Cs distribution coefficient and the maximum Cs loading capacity in the AP-107 tank waste matrix. Batch contact testing helps to evaluate CST performance on tank waste supernate and is often used prior to processing tank waste through ion exchange columns to assess some performance metrics (e.g., 50% Cs breakthrough). Batch contact tests were performed with the filtered AP-107 tank waste at four Cs concentrations at a phase ratio of 200 (liquid volume to exchanger mass). The distribution coefficient (K d ) at the equilibrium condition of 9.2 µg Cs/mL (AP-107 feed condition) was determined to be 806 mL AP 107/g CST. With a CST bed density of 1.01 g/mL (<25 mesh CST), this K d corresponded to a predicted 50% Cs breakthrough of 814 bed volumes (BVs). The Cs load capacity at the equilibrium feed condition was determined to be 8.3 mg Cs/g dry CST. The three-column format testing was prototypic to the intended TSCR operations, albeit on a small scale with 10-mL CST beds. Flowrate was adjusted to match the CST contact time expected for the full-scale operation, i.e., matched bed volumes per hour (BV/h) flow rate. The feed was processed downflow through the lead column, then through the middle column, and then through the polish column. Loading continued at an average of 1.88 BV/h (1.83 to 2.04 BV/h range) until the entire available AP-107 feed was processed. The Cs-decontaminated product will be provided for vitrification testing. The lead column only reached 45% Cs breakthrough after processing 855 BVs of feed. The 50% Cs breakthrough was extrapolated to occur at ~900 BVs. This extrapolated 50% Cs breakthrough value differed from the batch contact estimate (814 BVs) by 13%. The waste acceptance criteria (WAC) or contract limit for the WTP LAW vitrification facility is 3.18E-5 Ci 137 Cs per mole Na. For the AP-107 tank waste, only 0.127% of the influent 137 Cs concentration may be delivered to the WTP; this required a Cs decontamination factor of 787. The Cs effluent from the middle column reached the WAC after processing 590 BVs. Cs breakthrough from the polish column began at 590 BVs, reaching 6.3E-3 µCi/mL or 4.3E-3% Cs breakthrough after processing 844 BVs of feed.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS1972

What makes active regions grow.

A study of magnetic flux growth or growth failure in over 100 active regions is shown to indicate that most growth is connected with the emergence of a large batch of flux in the shape of a new arch filament system (AFS). During the recent sunspot maximum, new AFSs appeared at a rate of nearly one per day over the entire sun. Evidence is presented for two proposed hypotheses, namely: (1) a twist in the flux tubes of new AFSs is a key factor in determining which new AFSs will grow; and (2) this twist is related to the well-known asymmetry of sunspot groups.

Weart, S.↗
DOE OSTI2019

Additive Manufacturing: Assessing Metal Powder Quality Through Characterizing Feedstock and Contaminants

The quality of powder feedstock for additive manufacturing (AM) metal powder bed fusion methods can significantly affect the quality of parts built from it. Particle size distribution (PSD) and shape factors influence flowability as well as the thickness and uniformity of each powder layer in the build box. For high-performance applications such as aerospace, medical, power generation and military, it becomes important to identify critical additional factors: the types, numbers and sizes of particulate contaminants that may be present in the powder. This is true for virgin, used and blended powders. Contaminants may be introduced during powder manufacture (e.g., ceramic insulation fragments from gas atomization equipment), handling (building insulation, talc) or possibly during the build process itself. Contaminants contained within a batch of powder can be physically built into an additive part when they are incorporated into the melt pool, and they can remain as discrete particulates or non-fused interfaces that act as stress concentrators. Their presence may decrease fatigue life by increasing the likelihood of fatigue crack initiation. This article describes three methods to rapidly and quantifiably characterize powder feedstock. (1) Computer-controlled scanning electron microscopy (CCSEM) provides quantitative size and shape parameters, as well as fine surface details from individual images on a particle-by-particle basis in large populations of powder. (2) Energy-dispersive spectroscopy (EDS) can be included, providing insights into variations within a batch of powder, as well as contaminant compositions. (3) For critical applications, the heavy liquid separation (HLS) method physically extracts low-density contaminants from a sample of powder metal down to part-per-billion detection limits to allow direct examination of contaminants and enhance identification and prevention of their sources. Altogether, these methods permit direct comparisons among powder metal samples. Better quantification of powder characteristics aids determination of suitability for end uses.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Hydrothermal Liquid Recovery of Rare Earth Elements and Critical Materials

This project demonstrated the technical viability of using tunable hydrothermal liquid (HTL) solutions to recover valuable minerals from a range of source materials. The effort focused upon rare earth elements (REE) and other minerals critical to the industrial security of the United States. This effort demonstrated, for the first time, that s, supercritical water (SCW) in particular, can: Extract critical and valuable minerals from a range of matrices ranging from rock ore to biomass; The process can be used to recover a wide range of minerals; This novel extraction chemistry can be cheap, simple, and nontoxic/”green”: The chemical extraction uses water, the cheapest industrial acid (sulfuric), and simple salts (i.e. sodium sulfate). However, other acids, salts, and additives could be used as appropriate. This Laboratory Directed Research and Development (LDRD) project identified that the process is complex with many interacting factors, but the benefits are significant if the complexities can be resolved. Challenges remain in the development of this technology and are described in this report. However, the results are positive, and commercial partners have already expressed interest. In summary, a novel, green, inexpensive mineral extraction process has been developed and demonstrated in a small batch reactor system. The effort provided information for an invention disclosure, proposal to DOE, and will support future business development efforts.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗