Search NASA⌕ Search

SEARCH · Search NASA

Results for “ISOTOPE SEPARATION”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Liquid centrifugation-based isotope separation of 7 Li, 37 Cl and D

Liquid centrifugation is an emerging method to separate isotopes. By spinning a liquid containing target isotopes (e.g., pure chemical or solution), the heavier isotope will be enriched at the outer part of a centrifuge, and the lighter ones will be enriched at the inner part of a centrifuge. The separation capability is positively correlated with rotation speed, outer radius and mass difference between isotopes to separate. This award targets to understand whether liquid centrifugation is effective in separating isotopes important for nuclear fission technologies. The results include the following three sections: 1) Effects of solute concentration on isotope separation; 2) Preliminary progress of building a low-speed countercurrent centrifuge, and 3) Analysis on possible candidates for 7 Li and 37 Cl. The award trained one research scientist, one Ph.D. student, one master student, and one undergraduate on liquid centrifugation and isotope measurements.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2023

Liquid solution centrifugation for safe, scalable, and efficient isotope separation

A general method of separating isotopes by centrifuging dissolved chemical compounds in a liquid is introduced. This technique can be applied to almost all elements and leads to large separation factors. The method has been demonstrated in several isotopic systems including Ca, Mo, O, and Li with single-stage selectivities of 1.046 to 1.067 per neutron mass difference (e.g., 1.43 in 40 Ca/ 48 Ca), which are beyond the capabilities of various conventional methods. Equations are derived to model the process, and the results agree with those of the experiments. The scalability of the technique has been demonstrated by a three-stage enrichment of 48 Ca with a total 40 Ca/ 48 Ca selectivity of 2.43, and the scalability is more broadly supported through analogies to gas centrifuge, whereby countercurrent centrifugation can further multiply the separation factor by 5 to 10 times per stage in a continuous process. Optimal centrifuge conditions and solutions can achieve both high-throughput and highly efficient isotope separation.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2015

Recent advances in SRS on hydrogen isotope separation using thermal cycling absorption process

TCAP (Thermal Cycling Absorption Process) is a gas chromatograph in principle using palladium in the column packing, but it is unique in the fact that the carrier gas, hydrogen, is being isotopically separated and the system is operated in a semi-continuous manner. TCAP units are used to purify tritium. The recent TCAP advances at Savannah River Site (SRS) include compressor-free concept for heating/cooling, push and pull separation using an active inverse column, and compact column design. The new developments allow significantly higher throughput and better reliability from 1/10 of the current production system's footprint while consuming 60% less energy. Various versions are derived in the meantime for external customers to be used in fusion energy projects.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
NASA NTRS1975

Possible application of laser isotope separation

The laser isotope separation process is described and its special economic features discussed. These features are its low cost electric power operation, capital investment costs, and the costs of process materials.

Delionback, L. M.↗
DOE OSTI2014

High Specific Activity Sm-153 By Post Irradiation Isotope Separation (Final Scientific Technical Report)

The isotope, samarium-153 ( 153 Sm) has ideal nuclear properties well suited for a variety of therapeutic applications; however, it is only available with low specific activity (radioactivity per unit mass) due to the method of production. Commercially useful quantities can be made by the 152 Sm (n,γ) 153 Sm reaction in a nuclear reactor, but typical irradiation parameters result in less than 2% of the 152 Sm target material being converted, leading to a very diluted end product. Since chemical processing methods cannot be used to perform isotopic separation, this means that >98% of the resultant pharmaceutical molecules are labeled with “cold” target atoms and are incapable of providing any radiation-induced therapeutic effect. The goals of this project were to introduce a new approach to the production of high specific activity (HSA) 153 Sm utilizing electromagnetic isotope separation (EMIS), and to perform biodistribution and chemistry studies with such HSA 153 Sm to test labeling capability with targeting molecules. Included in these studies was the successful development of a collection substrate that would allow the efficient deposit and removal of 153 Sm; to this end, DLC (diamond like carbon) foils were successfully employed. In the first year of this project a surface ion source was developed, leading to the successful production of a mass separated beam of stable Sm ions. Studies were then performed using similar apparatus at the Oak Ridge National Laboratory, leading to a well-separated beam of isotopically pure samarium ions. This was followed by the successful production of four 15 mCi samples (over a 7 month period) of HSA 153 Sm which were delivered to the IsoTherapeutics Group for biodistribution and chemical labeling studies. Such samples were produced by neutron irradiation of 5 mg metal samples of 152 Sm at the HFIR (ORNL High Flux Isotope Reactor), followed by manual transfer of the samples from the irradiation capsule to the chamber of a surface ion source. Isotopic beams were then extracted using the IRIS2 EMIS facility, and collected onto 10 μm thick DLC foils. The samples were irradiated for 10 h periods, with typical collection periods lasting 12 - 16 h. Employing appropriate chemical approaches, these HSA 153 Sm samples were evaluated for labeling with small, medium and large molecules. The ability to label a variety of targeting molecules is important to demonstrate the potential therapeutic capabilities. Biodistribution studies, using HSA 153 Sm with the bone agent DOTMP, in rodents demonstrated that the biodistribution is similar to what is observed with LSA 153 Sm. Labeling was successfully achieved with peptides, and large protein molecules.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2023

Simulation studies for beam commissioning at FRIB Advanced Rare Isotope Separator

The Facility for Rare Isotope Beams (FRIB) includes a powerful superconducting driver accelerator and an Advanced Rare Isotope Separator (ARIS). The ARIS collects and purifies the rare isotope fragments of interest for experiments in nuclear physics, nuclear astrophysics, fundamental symmetries, etc. ARIS consists of a vertical pre-separator and downstream horizontal separator section (C-Bend). Each section can provide a high-resolution separation alternatively. The resolution reduction due to the emittance induced by momentum compression can be avoided by isotope separation in different dispersive planes. Beam commissioning of ARIS for the first experiments was completed and demonstrated particle identification of fragments. The beam tuning in ARIS largely relies on numerical simulations since the limited space for diagnostics. Here, we report the result of the beam trajectory correction, transverse matching, and beam-based misalignment studies at ARIS.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2011

Influence of liquid structure on diffusive isotope separation in molten silicates and aqueous solutions

Molecular diffusion in natural volcanic liquids discriminates between isotopes of major ions (e.g., Fe, Mg, Ca, and Li). Although isotope separation by diffusion is expected on theoretical grounds, the dependence on mass is highly variable for different elements and in different media. Silicate liquid diffusion experiments using simple liquid compositions were carried out to further probe the compositional dependence of diffusive isotopic discrimination and its relationship to liquid structure. Two diffusion couples consisting of the mineral constituents anorthite (CaAl{sub 2}Si{sub 2}O{sub 8}; denoted AN), albite (NaAlSi{sub 3}O{sub 8}; denoted AB), and diopside (CaMgSi{sub 2}O{sub 6}; denoted DI) were held at 1450°C for 2 h and then quenched to ambient pressure and temperature. Major-element as well as Ca and Mg isotope profiles were measured on the recovered quenched glasses. In both experiments, Ca diffuses rapidly with respect to Si. In the AB–AN experiment, D{sub Ca}/D{sub Si} ~ 20 and the efficiency of isotope separation for Ca is much greater than in natural liquid experiments where D{sub Ca}/D{sub Si} ~ 1. In the AB–DI experiment, D{sub Ca}/D{sub Si} ~ 6 and the efficiency of isotope separation is between that of the natural liquid experiments and the AB–AN experiment. In the AB–DI experiment, D{sub Mg}/D{sub Si} ~ 1 and the efficiency of isotope separation for Mg is smaller than it is for Ca yet similar to that observed for Mg in natural liquids. The results from the experiments reported here, in combination with results from natural volcanic liquids, show clearly that the efficiency of diffusive separation of Ca isotopes is systematically related to the solvent-normalized diffusivity—the ratio of the diffusivity of the cation (D{sub Ca}) to the diffusivity of silicon (D{sub Si}). The results on Ca isotopes are consistent with available data on Fe, Li, and Mg isotopes in silicate liquids, when considered in terms of the parameter D{sub cation}/D{sub Si}. Cations diffusing in aqueous solutions display a similar relationship between isotopic separation efficiency and D{sub cation} =D{sub H 2 O} , although the efficiencies are smaller than in silicate liquids. Our empirical relationship provides a tool for predicting the magnitude of diffusive isotopic effects in many geologic environments and a basis for a more comprehensive theory of isotope separation in liquid solutions. We present a conceptual model for the relationship between diffusivity and liquid structure that is consistent with available data.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2015

Separative analyses of a chromatographic column packed with a core-shell adsorbent for lithium isotope separation

Lithium-6 is used as a blanket material for sufficient tritium production in DT fueled fusion reactors. A core-shell type adsorbent was proposed for lithium isotope separation by chromatography. The mass transfer model in a chromatographic column consisted of 4 steps, such as convection and dispersion in the column, transfer through liquid films, intra-particle diffusion and and adsorption or desorption at the local adsorption sites. A model was developed and concentration profiles and time variation in the column were numerically simulated. It became clear that core-shell type adsorbents with thin porous shell were saturated rapidly relatively to fully porous one and established a sharp edge of adsorption band. This is very important feature because lithium isotope separation requires long-distance development of adsorption band. The values of HETP (Height Equivalent of a Theoretical Plate) for core-shell adsorbent packed column were estimated by statistical moments of the step response curve. The value of HETP decreased with the thickness of the porous shell. A core-shell type adsorbent is, then, useful for lithium isotope separation. (authors)

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2023

An Overview of the Radioisotope Electromagnetic Isotope Separation Capabilities at Idaho National Laboratory

Electromagnetic isotope separation (EMIS) has been an effective tool for the enrichment of isotopes for over 80 years. In the early 1990’s the U.S. reduced or eliminated electromagnetic isotope separation capabilities, but in the last decade, increased demand for both stable and radioactive enriched isotopes have led to the reestablishment of small-medium scale EMIS capabilities in the U.S. National Laboratory Complex.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2016

Selective IR multiphoton dissociation of molecules in a pulsed gas-dynamically cooled molecular flow interacting with a solid surface as an alternative to low-energy methods of molecular laser isotope separation

We report the results of studies on the isotope-selective infrared multiphoton dissociation (IR MFD) of SF{sub 6} and CF{sub 3}I molecules in a pulsed, gas-dynamically cooled molecular flow interacting with a solid surface. The productivity of this method in the conditions of a specific experiment (by the example of SF{sub 6} molecules) is evaluated. A number of low-energy methods of molecular laser isotope separation based on the use of infrared lasers for selective excitation of molecules are analysed and their productivity is estimated. The methods are compared with those of selective dissociation of molecules in the flow interacting with a surface. The advantages of this method compared to the low-energy methods of molecular laser isotope separation and the IR MPD method in the unperturbed jets and flows are shown. It is concluded that this method could be a promising alternative to the low-energy methods of molecular laser isotope separation. (laser separation of isotopes)

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2022

Advanced Isotope Separation Technology for Fusion Fuel

Deuterium-tritium fusion is the easiest nuclear fusion reaction among known fusion reactions. Since tritium is extremely rare, it is artificially produced by irradiating lithium metal. The separation, isolation, and storage of the tritium isotope has been a major focus of the Savannah River Site (SRS) for many decades. Thermal diffusion, fractional absorption, and cryogenic distillation have all been used in the past, and each has significant operational and safety challenges. A process known as the Thermal Cycling Absorption Process (TCAP) was invented at SRS, and because of its overwhelming advantages in safety, efficiency, size, and reduced tritium inventory, it has replaced all other hydrogen isotope separation processes at SRS. Here, the working principles and current development of hydrogen isotope separation using TCAP at SRS are explained as a potential advanced isotope separation process for the fusion fuel cycle.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2020

Isotope separation methods and systems

Methods and systems for the separation of isotopes from an aqueous stream are described as can be utilized in one embodiment to remove and recover tritium from contaminated water. Methods include counter-current flow of an aqueous stream on either side of a separation membrane. The separation membrane includes an isotope selective layer (e.g., graphene) and an ion conductive supporting layer (e.g., Nafion®). An electronic driving force encourages passage of isotopes selectively across the membrane to enrich the flow in the isotopes.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2022

Modeling Isotope Separation in Electrochemical Lithium Deposition

Naturally occurring Li consists of two stable isotopes, 6 Li with an abundance of about 7.5%, and 7 Li making up the remainder with 92.5%. The development of a 6 Li enrichment technique, in terms of technical reliability and environmental safety to reach 6 Li future requirements, represents a key step in the roadmap for nuclear fusion energy supply worldwide. This paper uses finite element analysis-based models to simulate electrochemical Li isotope separation, which is an attractive method in terms of simplicity, safety, and scalability. In the model, we quantitatively analyze how different electrochemical factors including thermodynamics, charge-transfer kinetics, and diffusivities affect the separation process (separation factor), together with cell parameters, such as cell length and current density. The maximum separation factor of 1.128 could be obtained with the cell under the optimal thermodynamic, kinetic, and diffusive conditions, which is among the highest separation factors ever reported. Furthermore, these results will assist in designing the actual isotope separation setup with large separation factor and appropriate timing for sample collection.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2021

A Comprehensive Review of Selected Major Categories of Lithium Isotope Separation Techniques

The ability to generate materials with an enriched isotopic abundance, that is one that differs from natural abundance, is critical in terms of technology. Isotopes are used in a wide range of applications, including radioactive tracers, nondestructive tests, radiotherapy in human medicine, nuclear fuels, and isotope‐substituted compounds for chemistry and biology research, as well as environmental geochemical signature tracers. A commonly discussed research topic is the isotopic separation of various elements—uranium, hydrogen, lithium, and iodine, among many others. Among these isotopes, lithium isotopes are especially important in various applications including strategic areas. These isotopes are light and hence their separation techniques are not very obvious. Herein, all the main categories of Li isotope separation are reviewed in depth with a focus on electrochemical technologies for stable lithium isotope separation.

Murali, Arun↗
DOE OSTI2022

Hydrogen isotope separation methods and systems

Methods and systems for the separation of hydrogen isotopes from one another are described. Methods include utilization of a hydrogen isotope selective separation membrane that includes a hydrogen isotope selective layer (e.g., graphene) and a hydrogen ion conductive supporting layer. An electronic driving force encourages passage of isotopes selectively across the membrane at an elevated separation temperature to enrich the product in a selected hydrogen isotope.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2016

High efficiency noble gas electron impact ion source for isotope separation

An electron impact ion source has been designed for generation of noble gas ions in a compact isotope separator. The source utilizes a circular filament that surrounds an ionization chamber, enabling multiple passes of electrons through the ionization chamber. This report presents ion optical design and the results of efficiency and sensitivity measurements performed in an ion source test chamber and in the compact isotope separator. The cylindrical design produced xenon ions at an efficiency of 0.37% with a sensitivity of ~24 µA /Pa at 300 µA of electron current.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2010

Efficient isotope separation by single-photon atomic sorting

We propose a general and scalable approach to isotope separation. The method is based on an irreversible change of the mass-to-magnetic moment ratio of a particular isotope in an atomic beam, followed by a magnetic multipole whose gradients deflect and guide the atoms. The underlying mechanism is a reduction of the entropy of the beam by the information of a single scattered photon for each atom that is separated. We numerically simulate isotope separation for a range of examples, which demonstrate this technique's general applicability to almost the entire periodic table. The practical importance of the proposed method is that large-scale isotope separation should be possible, using ordinary inexpensive magnets and the existing technologies of supersonic beams and lasers.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2026

Toward Hydrogen Isotope Separations through Strong Hydrogen Adsorption at Open Copper(I) Sites in an Ultramicroporous Metal-Organic Framework

Metal-organic frameworks with coordinatively unsaturated metal sites (open metal sites) capable of engaging in orbital interactions with pi-acidic gases are of interest for enabling ambient-temperature gas separations, such as hydrogen isotope separations. In view of the weakly pi-acidic nature of H2, we sought to strengthen pi-backbonding-mediated H2 adsorption through pore confinement effects. Toward that end, we synthesized and characterized the ultramicroporous metal-organic framework CuxZn5-xCl4-yHz(bbta)3 (CuIZn-MFU-4; H2bbta = 1H,5H-benzo(1,2-d:4,5-d')bistriazole), featuring pi-basic trigonal pyramidal CuI sites that reside within 7 A of one another at their closest. Gas adsorption measurements reveal an H2 adsorption enthalpy of -38 kJ/mol, exceeding that of the larger-pore analog (CuIZn-MFU-4l; -33 kJ/mol) and representing the strongest H2 adsorption yet achieved in a metal-organic framework. The stronger H2 adsorption in CuIZn-MFU-4 is attributed to a combination of pore confinement effects and the increased ..sigma..-accepting nature of the CuI sites caused by a more electron-withdrawing bbta2- linker, as supported by structural, spectroscopic, and computational evidence. With the strongest H2 adsorption, equilibrium isotope effects in CuIZn-MFU-4 lead to a D2/H2 selectivity (as estimated by ideal adsorbed solution theory) of 1.35 even at 298 K, approaching the values reported below 200 K for conventional porous materials.

08 HYDROGEN↗