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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 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Purification of industrial grade lithium chloride for the recovery of high purity battery grade lithium carbonate

Due to lithium’s high energy along with other exceptional characteristics, lithium demand across many industries is rising, specifically for Li-batteries. Thus, a sufficient supply of high purity lithium is vital in order for these significant technologies to develop. In the current work, industrial grade lithium chloride has been successfully treated with four simple precipitation steps to obtain a high purity battery grade lithium carbonate of >99.95%. The LiCl starting solutions contained K, Na, Mg, Ca, Cu, Ni, and Fe chloride contaminants and solutions of 2.5 to 10 M were simulated. The heavier metals and the majority of Mg were removed in a single step with an increase in pH. The removal of Ca and remaining Mg was executed by sodium oxalate addition where the calcium levels of the 10 M were able to be reduced to 5–6 ppm in solution. It appeared that the higher molarity and ionic strength of the LiCl solution aided in obtained higher degrees of impurity removal. Lastly, high purity Li 2 CO 3 was obtained by first precipitating from brine solution, followed by a second purification step with pressurized CO 2 . The second step allowed for the removal of entrapped Na and K after the first precipitation, resulting in >99.95 wt% purity Li 2 CO 3 .

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Electrification and decarbonization of spent Li-ion batteries purification by using an electrochemical membrane reactor

The expanding electric vehicle market brings with it exponential growth in the use of lithium (Li)-ion batteries (LIB) for which a wave of spent LIB is expected to come within the next 5 to 10 years. Due to the economic and strategic value imbedded within the metals contained in LIB, different recycling technologies, including hydrometallurgy, pyrometallurgy and direct recycling, are under development. Being different from previous hydrometallurgical methods, which may have high chemical consumption and negative environmental impact, an electrochemical membrane reactor is designed and validated for the first time, to electrify and decarbonize the impurity removal process. This reactor electroplates copper (Cu) and electrochemically precipitates aluminum (Al) and iron (Fe) from simulated spent LIB leachates, by consuming only air, water, and electricity, and the impurities are reduced to <1 ppm. The purified leachate maintains 99.5 % of the nickel (Ni), 95.4 % of the cobalt (Co) and 99.14 % of manganese (Mn) from the original leachate solution, and then can be directly applied for cathode precursor synthesis. Additionally, the purification process doesn’t introduce extra impurity, and the reactor restoration process generates valuable by-product hydro sulfate (H2SO4). This electrochemical process can reduce the cost, because of the much less chemical consumption and the valuable by-product generation, and mitigates the waste emissions, because of no extra impurity introduced and no greenhouse gas (GHG) produced. In conclusion, the chemical precipitation method uses significant amount of NaOH, which induced GHG emission during the manufacturing process.

25 ENERGY STORAGE↗
DOE OSTI2021

High-temperature corrosion of a nickel-based alloy in a molten chloride environment – The effect of thermal and chemical purifications

There is currently an ever-increasing demand for higher process efficiencies in next generation (Gen3) concentrating solar power (CSP). Higher process efficiencies may be procured by increasing the operating temperature, and simultaneously, minimizing the degradation of materials used for construction of CSP plants (e.g., piping, thermal storage tanks, solar receivers and heat exchangers). Thus, understanding materials corrosion in the presence of molten salt mixtures used as thermal energy storage media and heat transfer fluids is indispensable for CSP development. The present paper provides insights into the effects of salt purification on the corrosion of a nickel-based alloy (Haynes 230) isothermally exposed to a stagnant chloride-based salt mixture at 800 °C. The MgCl 2 -based salt mixture was thermally dehydrated and chemically treated with (0.1 and 0.5 wt %) elemental magnesium. Results reveal the electrochemical nature of the corrosion process, and the formation of corrosion products such as oxides (MgO, MgCr 2 O 4 , and MgAl 2 O 4 ) and nitrides (CrN) on the alloy surface and in sub-surface regions. Magnesium additions enhanced the ability to resist corrosion by reducing the concentration of impurities (H 2 O, MgOH + , OH - species) and polarizing the alloy surface. The formation of nitrides in all cases studied indicates the impact of using nitrogen as a protective gas in the system. Results also reveal that a single step treatment of the salt using metallic Mg could be considered as a measure to control the salt's impurity level, e.g., if required for system control.

14 SOLAR ENERGY↗
DOE OSTI2014

Facile purification and click labeling with 2-[ 18 F]fluoroethyl azide using solid phase extraction cartridges

In this paper, a facile method was developed to purify 2-[ 18 F]fluoroethyl azide ([ 18 F]FEA) using a C18 cartridge and an Oasis® HLB cartridge in series, in which [18F]FEA was exclusively trapped on the HLB cartridge. [ 18 F]FEA can be eluted for reactions in solution; alternatively click labeling can be carried out on the HLB cartridge itself by loading an alkyne substrate and copper (I) catalyst dissolved in DMF onto the cartridge. Finally, this solid phase extraction methodology for purification and click labeling with [ 18 F]FEA, either in solution or on the cartridge, is safe, simple, reproducible in high yield, and compatible with automated synthesis of 18 F-labeled PET tracers.

2-Fluoroethyl azide↗
DOE OSTI2018

Highly Selective and Permeable Microporous Polymer Membranes for Hydrogen Purification and CO2 Removal from Natural Gas

This paper reports a new macromolecular design that incorporates hierarchical triptycene unit into thermally rearranged polybenzoxazole (TR-PBO) structures for highly selective and permeable gas separation membranes with great potential for H2 purification and CO2 removal from natural gas. We demonstrate that triptycene moieties not only effectively disrupt chain packing enabling microporous structure for fast mass transport, but also introduce ultra-fine microporosity via the unique internal free volume intrinsic to triptycene unit that allows for superior molecular sieving capability in resulting PBO membranes. Consequently, these triptycene-based polybenzoxazole (TPBO) membranes display among the highest gas selectivities for H2 separations (i.e., a(H2/N2) = 6; a(H2/CH4) = 203) and CO2 removal from natural gas (i.e., a(CO2/CH4) = 68) among existing glassy polymeric membranes. It is also demonstrated that microporous structure and gas transport properties of TPBO films are highly tailorable by adjusting the triptycene content and the ortho-functionality of the precursors. The highly diverse tunability, along with the excellent resistance towards membrane plasticization and physical aging, render the TPBO membranes with extremely versatile separation capability applicable for a wide range of important industrial processes to get clean or low carbon fuels and reduce carbon footprint.

Luo, Shuangjiang↗
DOE OSTI2016

Probing Metal–Organic Framework Design for Adsorptive Natural Gas Purification

Parent and amine-functionalized analogues of metal–organic frameworks (MOFs), UiO-66(Zr), MIL-125(Ti), and MIL-101(Cr), were evaluated for their hydrogen sulfide (H 2 S) adsorption efficacy and post-exposure acid gas stability. Adsorption experiments were conducted through fixed-bed breakthrough studies utilizing multicomponent 1% H 2 S/99% CH 4 and 1% H 2 S/10% CO 2 /89% CH 4 natural gas simulant mixtures. Instability of MIL-101(Cr) materials after H 2 S exposure was discovered through powder X-ray diffraction and porosity measurements following adsorbent pelletization, whereas other materials retained their characteristic properties. Linker-based amine functionalities increased H 2 S breakthrough times and saturation capacities from their parent MOF analogues. Competitive CO 2 adsorption effects were mitigated in mesoporous MIL-101(Cr) and MIL-101–NH 2 (Cr), in comparison to microporous UiO-66(Zr) and MIL-125(Ti) frameworks. This result suggests that the installation of H 2 S binding sites in large-pore MOFs could potentially enhance H 2 S selectivity. In situ Fourier transform infrared measurements in 10% CO 2 and 5000 ppm H 2 S environments suggest that framework hydroxyl and amine moieties serve as H 2 S physisorption sites. In conclusion, results from this study elucidate design strategies and stability considerations for engineering MOFs in sour gas purification applications.

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

Suspended Membrane Evaporators Integrating Environmental and Solar Evaporation for Oily Wastewater Purification

Solar-driven evaporation is promising in oily wastewater treatment, in particular for emulsions, but conventional evaporators suffer from pore blocking by residual oil or contamination by volatile oil compounds in the condensed water. In the current research, we develop a suspended membrane evaporator integrating solar evaporation with oil-in-water emulsion separation. The heating and evaporating interface is separated from the rejecting interface to avoid oil escape and improve heat management. A temperature gradient forms on the membrane surface that can promote evaporation performance by combining both solar and environmental evaporation. Such an evaporator achieves a maximum evaporation rate of 1.645 kg/(m 2 ·h) as well as an apparent evaporation efficiency of 111.9%. Moreover, the superhydrophilic and superoleophobic membrane shows excellent oil repellence and emulsion rejection, which can achieve an oil removal efficiency above 98.8% in oil-in-water emulsion separation, and high evaporation rate recovery in cycling tests. Furthermore, a scaled-up membrane evaporator array produces ~8 kg/(m 2 ·d) of clean water from oily wastewater in outdoor experiments, further demonstrating the strong purification performance of this evaporator in oily wastewater treatment.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Mapping Composition Evolution through Synthesis, Purification, and Depolymerization of Random Heteropolymers

Random heteropolymers (RHPs) consisting of three or more comonomers have been routinely used to synthesize functional materials. While increasing the monomer variety diversifies the side-chain chemistry, this substantially expands the sequence space and leads to ensemble-level sequence heterogeneity. Most studies have relied on monomer composition and simulated sequences to design RHPs, but the questions remain unanswered regarding heterogeneities within each RHP ensemble and how closely these simulated sequences reflect the experimental outcomes. Here, we quantitatively mapped out the evolution of monomer compositions in four-monomer-based RHPs throughout a design-synthesis-purification-depolymerization process. By adopting a Jaacks method, we first determined 12 reactivity ratios directly from quaternary methacrylate RAFT copolymerization experiments to account for the influences of competitive monomer addition and the reversible activation/deactivation equilibria. The reliability of in silico analysis was affirmed by a quantitative agreement (<4% difference) between the simulated RHP compositions and the experimental results. Furthermore, we mapped out the conformation distribution within each ensemble in different solvents as a function of monomer chemistry, composition, and segmental characteristics via high-throughput computation based on self-consistent field theory (SCFT). These comprehensive studies confirmed monomer composition as a viable design parameter to engineer RHP-based functional materials as long as the reactivity ratios are accurately determined and the livingness of RHP synthesis is ensured.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Extraction, purification, and reuse of dyes from coloured polyester textiles

The removal of dyes from coloured textile waste represents a sustainable approach to textile recycling, enabling the recovery of valuable chemical, and material resources that would otherwise be discarded. Up to 40% of the greenhouse gas emissions from textiles originate from dye production, making efficient recycling of dyes a major opportunity for curbing emissions and minimizing waste in both textile manufacturing and recycling. Here, in this study, we demonstrate a process for the extraction, purification, and reuse of mixed dyes from polyester textiles using bio-based, non-hazardous solvents selected on the basis of computational predictions for polyester and dye solubilities. Extracted dyes are purified to individual compounds using counter-current chromatography and analysed via liquid chromatography-mass spectrometry. Post-extraction characterization of the extracted dyes and polymer substrate confirms dye colour retention and polyester fabric property preservation. Dye recycling is demonstrated by redyeing colour-free fabrics with the recovered dyes. We further show a potential process configuration for dye removal using a flow-through reactor packed with a textile substrate. The proposed dye removal process produces reusable, recyclable dyes, and dye-free fabrics, thus facilitating textile recycling.

36 MATERIALS SCIENCE↗
DOE OSTI2016

DMR (deacetylation and mechanical refining) processing of corn stover achieves high monomeric sugar concentrations (230 g L -1 ) during enzymatic hydrolysis and high ethanol concentrations (>10% v/v) during fermentation without hydrolysate purification or concentration

Distilling and purifying ethanol and other products from second generation lignocellulosic biorefineries adds significant capital and operating costs to biofuel production. The energy usage associated with distillation negatively affects plant gate costs and causes environmental and life-cycle impacts, and the lower titers in fermentation caused by lower sugar concentrations from pretreatment and enzymatic hydrolysis increase energy and water usage and ethanol production costs. In addition, lower ethanol titers increase the volumes required for enzymatic hydrolysis and fermentation vessels increase capital expenditure (CAPEX). Therefore, increasing biofuel titers has been a research focus in renewable biofuel production for several decades. In this work, we achieved approximately 230 g L -1 of monomeric sugars after high solid enzymatic hydrolysis using deacetylation and mechanical refining (DMR) processed corn stover substrates produced at the 100 kg per day scale. The high sugar concentrations and low chemical inhibitor concentrations achieved by the DMR process allowed fermentation to ethanol with titers as high as 86 g L -1 , which translates into approximately 10.9% v/v ethanol. To our knowledge, this is the first time that titers greater than 10% v/v ethanol in fermentations derived from corn stover without any sugar concentration or purification steps have been reported. As a result, the potential cost savings from high sugar and ethanol titers achieved by the DMR process are also reported using TEA analysis.

09 BIOMASS FUELS↗
DOE OSTI2015

Modular microfluidics for point-of-care protein purifications

Biochemical separations are the heart of diagnostic assays and purification methods for biologics. On-chip miniaturization and modularization of separation procedures will enable the development of customized, portable devices for personalized health-care diagnostics and point-of-use production of treatments. In this report, we describe the design and fabrication of miniature ion exchange, size exclusion and affinity chromatography modules for on-chip clean-up of recombinantly-produced proteins. Our results demonstrate that these common separations techniques can be implemented in microfluidic modules with performance comparable to conventional approaches. We introduce embedded 3-D microfluidic interconnects for integrating micro-scale separation modules that can be arranged and reconfigured to suit a variety of fluidic operations or biochemical processes. In conclusion, we demonstrate the utility of the modular approach with a platform for the enrichment of enhanced green fluorescent protein (eGFP) from Escherichia coli lysate through integrated affinity and size-exclusion chromatography modules.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Unexpected compositional and structural modification of CoPt 3 nanoparticles by extensive surface purification

We combined synchrotron small angle X-ray scattering, X-ray fluorescence and extended X-ray absorption fine structure spectroscopy to probe the structure of chemically synthesized CoPt 3 nanoparticles (NPs) after ligand removal via the commonly accepted solvent/nonsolvent approach. We showed that the improved catalytic activity of extensively purified NPs could not be explained only in terms of a “cleaner” surface. We found that extensive surface purification results in the substantial leaching of the Co atoms from the chemically synthesized CoPt 3 NPs transforming them into CoPt 3 /Pt core/shell structures with an unexpectedly thick (~0.5 nm) Pt shell. We indicated that the improved catalytic activity of extensively purified NPs in octyne hydrogenation reaction can be explained by the formation of CoPt 3 /Pt core/shell structures. Also, we demonstrated that drastic compositional and structural transformation of water transferred CoPt 3 NPs was rather a result of extensive removal of native ligands via a solvent/nonsolvent approach than leaching of cobalt atoms in aqueous media. We expect that these findings can be relevant to other transition metal based multicomponent NPs.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Passivation-driven speciation, dealloying and purification

Thin passivating surface oxide layers on metal alloys form a dissipation horizon between dissimilar phases, hence harbour an inherent free energy and composition gradient. We exploit this gradient to drive order and selective surface separation (speciation), enabling redox-driven enrichment of the core by selective conversion of low standard reduction potential (E°) components into oxides. Additionally, coupling this oxide growth to volumetric changes during solidification allows us to create oxide crystallites trapped in a metal (‘ship-in-a-bottle’) or extrusion of metal fingerlings on the heavily oxidized particle. We confirm the underlying mechanism through high temperature X-ray diffraction and characterization of solidification-trapped particle states. We demonstrate that engineering the passivating surface oxide can lead to purification via selective dealloying with concomitant enrichment of the core, leading to disparate particle morphologies.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Purification of the output modes of overmoded relativistic backward wave oscillators

Successful suppression of mode competition in the beam-wave interaction process of overmoded relativistic backward wave oscillators (RBWOs) cannot ensure the output modes purity. Optimizing the magnitude and the phase of the mode conversion coefficients in the devices is significant for purifying the output modes. A universal method of purifying the TM{sub 01} and TM{sub 02} mixed modes output by overmoded RBWOs without decreasing the total output power is presented in this paper. With this method, we purify the TM{sub 01} and TM{sub 02} mixed modes generated in an X-band overmoded RBWO (D/λ ≈ 2.6) operated at the constant diode voltage of 730 kV. Dependence of modes purification effect on the variation of diode voltage is also analyzed in particle-in-cell simulation. Our analysis indicates that when the diode voltage is in the range of (730 ± 60) kV, the percentage of output power carried by TM{sub 01} mode will be higher than 95%.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2014

Separation of thorium (IV) from lanthanide concentrate (LC) and water leach purification (WLP) residue

Thorium (IV) content in industrial residue produced from rare earth elements production industry is one of the challenges to Malaysian environment. Separation of thorium from the lanthanide concentrate (LC) and Water Leach Purification (WLP) residue from rare earth elements production plant is described. Both materials have been tested by sulphuric acid and alkaline digestions. Th concentrations in LC and WLP were determined to be 1289.7 ± 129 and 1952.9±17.6 ppm respectively. The results of separation show that the recovery of Th separation from rare earth in LC after concentrated sulphuric acid dissolution and reduction of acidity to precipitate Th was found 1.76-1.20% whereas Th recovery from WLP was less than 4% after concentrated acids and alkali digestion processes. Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) was used to determine Th concentrations in aqueous phase during separation stages. This study indicated that thorium maybe exists in refractory and insoluble form which is difficult to separate by these processes and stays in WLP residue as naturally occurring radioactive material (NORM)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗