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Results for “chemical separations”

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 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Specific ion effects on ion transport in charged polymer membranes

Selective separation of like-charged ions is a central challenge in applications such as critical mineral recovery. Electrochemical membrane–based separations offer promising pathways to address this need, but a limited fundamental understanding of ion transport in charged polymer membranes hampers the development of highly selective materials. This study elucidates the role of specific ion effects (SIEs) in ion transport through charged polymer membranes by integrating experimental measurements of ion mobility and in situ ion/ion and ion/water interactions in model charged polymer membranes with results from molecular dynamics simulations on analogous systems. We demonstrate that solvent-mediated ion interactions drive pronounced SIEs within the studied membranes, with the ion softness, i.e., the malleability of ion hydration shells, from hard/soft acid/base (HSAB) theory emerging as a key predictor of transport properties. HSAB theory also explains the observed mechanism of solvent-mediated ion interactions. Our findings offer a mechanistic framework for designing membranes with tailored ion selectivity, potentially enabling efficient separations of chemically similar ions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Catalytic Fast Pyrolysis for Chemicals: Cooperative Research and Development, CRADA Number CRD-16-00637 (Final Report)

The purpose of this partnership between the ExxonMobil Chemical Company and NREL is to advance the state of the art for converting biomass to liquid hydrocarbons using catalytic fast pyrolysis (CFP), with particular emphasis on directing and improving yields of such liquid hydrocarbons for uses in commodity chemical markets. CFP of biomass is a promising route for the production of renewable fuels and chemicals, and the key driver for economic viability is carbon yield to valuable products. The majority of prior CFP work has been targeted at fuel production, but this CRADA seeks to pursue routes to chemical co-products, thereby enhancing the overall economic viability of CFP. This project is beneficial to the public because it advances a technology that could one day provide renewable fuels and chemicals to our economy, thus improving the sustainability of our transportation and chemical manufacturing sectors.

09 BIOMASS FUELS↗
DOE OSTI2025

Isolation and conversion of electrolyte components into a value-added product

The overall objective of this work was to develop a process for effectively (i) recycling the electrolyte components from the end-of-life batteries and reduce the environmental hazard, (ii) understand the fundamental differences between pristine and recycled electrolyte components, (iii) electrochemically and analytically evaluate the recycled electrolyte components and (iv) establish deviations from the pristine electrolyte, and effectively separation of value-added product. We focused on determining scaling up the electrolyte recovery process by distillation of end-of-life batteries to get yield enough to use it for electrolyte formulation of reuse in the battery cell. The used cells from the ORNL battery manufacture facility (BMF)as well as received from the industry partner, Austin Elements Inc., was scaled to 10 used multilayered pouch cells in each batch of distillation and systematically separated and identified the electrolyte components of the used cells with FTIR and NMR studies. We were able to recovery 10g of solvent mass from the used pouch cells. NMR spectroscopy showed that the solvent was pure EMC,DMC and the sample was used to make a new battery cell. The end-of-life battery, it was noted that some cells were visually drier than the other cells and were more advanced in aged. In that case, even though the same distillation conditions were utilized, no usable mass of electrolyte solvent was recovered. It is expected that most of the solvent was decomposed during the battery charge-discharge cycling. The solid salt residue was separated by chemical and water treatment processes. Components of resulting solid product was analyzed by XRD and XPS measurements. The solid products are very much related to the salts used in the electrolyte solution.

25 ENERGY STORAGE↗
DOE OSTI2025

Isolation and Conversion of Electrolyte Components into a Value-Added Product

The overall objective of this work was to develop a process for effectively (i) recycling the electrolyte components from the end-of-life batteries and reduce the environmental hazard, (ii) understand the fundamental differences between pristine and recycled electrolyte components, (iii) electrochemically and analytically evaluate the recycled electrolyte components and (iv) establish deviations from the pristine electrolyte, and effectively separation of value-added product. We focused on determining scaling up the electrolyte recovery process by distillation of end-of-life batteries to get yield enough to use it for electrolyte formulation of reuse in the battery cell. The used cells from the ORNL battery manufacture facility (BMF) as well as received from the industry partner, Austin Elements Inc., was scaled to 10 used multilayered pouch cells in each batch of distillation and systematically separated and identified the electrolyte components of the used cells with FTIR and NMR studies. We were able to recovery 10g of solvent mass from the used pouch cells. NMR spectroscopy showed that the solvent was pure EMC, DMC and the sample was used to make a new battery cell. The end-of-life battery, it was noted that some cells were visually drier than the other cells and were more advanced in aged. In that case, even though the same distillation conditions were utilized, no usable mass of electrolyte solvent was recovered. It is expected that most of the solvent was decomposed during the battery charge-discharge cycling. The solid salt residue was separated by chemical and water treatment processes. Components of resulting solid product was analyzed by XRD and XPS measurements. The solid products are very much related to the salts used in the electrolyte solution.

25 ENERGY STORAGE↗
DOE OSTI2021

Ironsand (Titanomagnetite-Titanohematite): Chemistry, Magnetic Properties and Direct Applications for Wireless Power Transfer

Ironsand is an abundant and inexpensive magnetic mineral resource. However, the magnetic properties of unprocessed ironsand are often inadequate for any practical applications. In this work, the applicability of ironsand for use as a component in a soft magnetic composite for large-scale inductive power transfer applications was investigated. After magnetic separation, the chemical, structural and magnetic properties of ironsand sourced from different locations were compared. Differences observed in the DC magnetic properties were consistent with changes in the chemical compositions obtained from X-ray Absorption Near-Edge Spectroscopy (XANES), which suggests varying the titanohematite to titanomagnetite content. Increased content in titanomagnetite and magnetic permeability correlated well with the total Fe content in the materials. The best-performing ironsand with the highest permeability and lowest core losses was used alongside Mn,Zn-Ferrite particles (ranging from ~100 μm to 2 mm) to fabricate toroid cores with varying magnetic material loading. It was shown that ironsand can be used to replace up to 15 wt.% of the magnetic materials with minimal impact on the composite magnetic performance, thus reducing the cost. Ironsand was also used as a supporting material in a single-rail wireless power transfer system, effectively increasing the power transfer, demonstrating potential applications to reduce flux leakage.

36 MATERIALS SCIENCE↗
DOE OSTI2024

The Isotopic Limit of Recycling

Despite advances in recycling technologies and practices, the world still mostly operates on a once-through materials use cycle. The once-through approach to the materials supply chain cannot work into perpetuity. The vast majority of current recycling efforts focus on mechanical or chemical separation-based techniques and are often subsequently limited on the number of times a component can be recycled or upcycled. By looking at things from a particle physics and nuclear history perspective, we propose a thought experiment to determine the physical limit of recycling and propose subsequent limits and standards to evaluate all recycling efforts. This uncommon approach to analysis demonstrates that the current limits to recycling are not physical in nature but engineering.

Lang, Eric↗
NASA NTRS1988

Oxygen extraction for a mission life support

Research conducted to extract oxygen from air or water with possible applications to oxygen production on Mars, the moon, or the Space Station is discussed. The technology under development involves an electrochemical process which is energy-efficient, regenerative and, in combination with a fuel cell, will provide net positive power, and generate oxygen for life support systems. The history of chemical oxygen separation and details of the oxygen separation technology are presented.

Carnevale, Steven J.↗
NASA NTRS1990

Reacting flows

Features of chemically reacting separated hypersonic flows are identified and issues concerning their analysis and simulation are discussed. Emphasis is placed on flows of high temperature dissociating and ionizing air and current methods for studying and characterizing these flows, including separation, are reviewed. The aeroassist orbital transfer vehicle and its flight trajectory are used for illustration. Thermochemical nonequilibrium phenomena are emphasized and extension of continuum analysis to the high altitude slip-flow regime is considered.

Deiwert, George S.↗
NASA NTRS1990

An empirical test for the metallicity sensitivity of the Cepheid period-luminosity relation

The results are reported of the first observational test of the sensitivity of the zero point of the Cepheid period-luminosity relation to metal abundance. BVRI time-averaged observations of Cepheids in three radially separated and chemically different fields in M31 are used to find mean reddenings and true distance moduli that differ by only 0.25 mag. Consistent distances are found for all three fields. The large observed differences in the apparent moduli can be totally attributed to different mean extinctions among the three fields.

Freedman, Wendy L.↗
NASA NTRS1993

Isotopic composition and concentration of sulfur in carbonaceous chondrites

New sulfur isotopic ratio measurements are reported for seven carbonaceous chondrites. Newly developed procedures permit measurement of delta S-33, delta S-34, and delta S-36 at precisions significantly greater than previously reported. A search for S-36 nucleosynthetic anomalies coproduced with anomalies in, for example, Ti-50 and Ca-48 was negative. The high endemic sulfur concentration probably dilutes any S-36 anomaly, and separation of individual sulfur phases may be needed to identify S-36 carrier phases. Large internal isotopic variations are observed, deriving from parent body and possibly nebular processes. Chondrule separates from Allende demonstrate isotopic compositions which vary as a function of diameter. High-temperature gas-solid exchange and a two-component mixing model may account for the observations. High-resolution isotopic data and structural information are reported for organic sulfur compounds separated by chemical extractions. The insoluble organics appear to be of either aliphatic or alicyclic structure and are dominant phases.

Gao, Xia↗
NASA NTRS1996

Highly Efficient Molecular Adsorbers

Molecular adsorbers developed to reduce contamination of sensitive optoelectronic components inside housings of scientific instruments. Contaminants stick to surfaces of these devices. Needed in situations in which simply venting contaminants to environment not an option because environment even more contaminating. Useful for variety of purposes in addition to suppressing contamination. Used as collection devices for sensitive total-mass-loss measurements on specimens of materials exhibiting low outgassing or as passive witness plates for collection of contaminants to be analyzed subsequently. Temperature-differential desorption from adsorbers used for preliminary separation of chemical species prior to mass spectroscopy or as alternative to gas chromatography/mass spectroscopy.

Voecks, Gerald E.↗
NASA NTRS1995

Capsule Aerothermodynamics. CFD Prediction Methodology; Database for CFD Validation; Capsule Flight Programs: AFE and Apollo Lessons Learned

Features of chemically reacting separated hypersonic flows are identified and issues concerning their analysis and simulation are discussed. Emphasis is placed on flows of high temperature dissociating and ionizing air and current methods for studying and characterizing these flows, including separation, are reviewed. The aeroassist orbital transfer vehicle and its flight trajectory are used for illustration. Thermochemical nonequilibrium phenomena are emphasized and extension of continuum analysis to the high altitude slip-flow regime is considered.

Deiwert, George S.↗
NASA NTRS2004

Multiplex coherent raman spectroscopy detector and method

A multiplex coherent Raman spectrometer (10) and spectroscopy method rapidly detects and identifies individual components of a chemical mixture separated by a separation technique, such as gas chromatography. The spectrometer (10) and method accurately identify a variety of compounds because they produce the entire gas phase vibrational Raman spectrum of the unknown gas. This is accomplished by tilting a Raman cell (20) to produce a high-intensity, backward-stimulated, coherent Raman beam of 683 nm, which drives a degenerate optical parametric oscillator (28) to produce a broadband beam of 1100-1700 nm covering a range of more than 3000 wavenumber. This broadband beam is combined with a narrowband beam of 532 nm having a bandwidth of 0.003 wavenumbers and focused into a heated windowless cell (38) that receives gases separated by a gas chromatograph (40). The Raman radiation scattered from these gases is filtered and sent to a monochromator (50) with multichannel detection.

Chen, Peter↗
NASA NTRS2010

Monolithically Integrated, Mechanically Resilient Carbon-Based Probes for Scanning Probe Microscopy

Scanning probe microscopy (SPM) is an important tool for performing measurements at the nanoscale in imaging bacteria or proteins in biology, as well as in the electronics industry. An essential element of SPM is a sharp, stable tip that possesses a small radius of curvature to enhance spatial resolution. Existing techniques for forming such tips are not ideal. High-aspect-ratio, monolithically integrated, as-grown carbon nanofibers (CNFs) have been formed that show promise for SPM applications by overcoming the limitations present in wet chemical and separate substrate etching processes.

Kaul, Anupama B.↗
NASA NTRS2003

Block Copolymers as Templates for Arrays of Carbon Nanotubes

A method of manufacturing regular arrays of precisely sized, shaped, positioned, and oriented carbon nanotubes has been proposed. Arrays of carbon nanotubes could prove useful in such diverse applications as communications (especially for filtering of signals), biotechnology (for sequencing of DNA and separation of chemicals), and micro- and nanoelectronics (as field emitters and as signal transducers and processors). The method is expected to be suitable for implementation in standard semiconductor-device fabrication facilities.

Bronikowski, Michael↗
DOE OSTI2020

[Challenges and Opportunities in] Process Modeling of Intensified Chemical Processes

Before the benefits of process intensification can be fully realized, a multitude of advances in process modeling will be necessary. Process intensification (PI) has the potential to speed development of chemical engineering innovations. Among its many benefits, PI can increase the driving forces (physical and/or chemical) for transport phenomena, separations, and/or reactions in chemical processes, and inspire novel process configurations with major technical and economic benefits. Examples of PI applications include integrated process units such as heat exchange networks, sorption- or membrane-enhanced reactors, and dividing-wall distillation columns, among others [AIChE(2017)].

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗