New Trends in Separation Techniques of Lithium Isotopes: A Review of Chemical Separation Methods

Abstract

In terms of isotopic technologies, it is essential to be able to produce materials with an enriched isotopic abundance (i.e., a compound isotopic labelled with 2H, 13C, 6Li, 18O or 37Cl), which is one that differs from natural abundance. The isotopic-labelled compounds can be used to study different natural processes (like compounds labelled with 2H, 13C, or 18O), or they can be used to produce other isotopes as in the case of 6Li, which can be used to produce 3H, or to produce LiH that acts like a protection shield against fast neutrons. At the same time, 7Li isotope can be used as a pH controller in nuclear reactors. The COLEX process, which is currently the only technology available to produce 6Li at industrial scale, has environmental drawbacks due to generation of Hg waste and vapours. Therefore, there is a need for new eco-friendly technologies for separation of 6Li. The separation factor of 6Li/7Li with chemical extraction methods in two liquid phases using crown ethers is comparable to that of COLEX method, but has the disadvantages of low distribution coefficient of Li and the loss of crown ethers during the extraction. Electrochemical separation of lithium isotopes through the difference in migration rates between 6Li and 7Li is one of the green and promising alternatives for the separation of lithium isotopes, but this methodology requires complicated experimental setup and optimisation. Displacement chromatography methods like ion exchange in different experimental configurations have been also applied to enrich 6Li with promising results. Besides separation methods, there is also a need for development of new analysis methods (ICP-MS, MC-ICP-MS, TIMS) for reliable determination of Li isotope ratios upon enrichment. Considering all the above-mentioned facts, this paper will try to emphasize the current trends in separation techniques of lithium isotopes by exposing all the chemical separation and spectrometric analysis methods, and highlighting their advantages and disadvantages.

Influence of molecular orientation on the photodissociation process of LiH molecules

“…The LiH molecule is also an excellent hydrogen storage material, which has important applications in the development of new energy [13][14][15]. Meanwhile, it also has been used as nuclear protection materials and reducing agents [16][17][18]. Photodissociation is the process in which a molecule absorbs photons, leading to the breaking of chemical bonds within the molecule [19][20][21][22].…”

Study on Flowability Regulation of Vacuum Gas-Atomized Fe-Cr-Ni-W-B Spherical Powder

“…Fe-W-B system materials are a novel ternary boride with a TiNiSi crystal structure and a high content of W and B (73.4% and 4.3% wt%, respectively) [ 1 ]; these materials exhibit a wide range of unusual physical and chemical properties at elevated temperatures [ 2 , 3 ]. These fascinating features open a wide range of possible applications for Fe-W-B, including nuclear shielding, microwires, petrochemicals, corrosion-resistant coating, and wear-resistant materials [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ].…”

“…These fascinating features open a wide range of possible applications for Fe-W-B, including nuclear shielding, microwires, petrochemicals, corrosion-resistant coating, and wear-resistant materials [4][5][6][7][8][9][10][11].…”

Purification of Quinoline Insolubles in Heavy Coal Tar and Preparation of Meso-Carbon Microbeads by Catalytic Polycondensation

“…Coal is an important chemical raw material [ 1 , 2 ], and a great amount of by-product coal tar is produced from the coal chemical industry every year [ 3 , 4 , 5 ]. The production of low-temperature coal tar produced by the coal chemical industry is especially abundant in the northern region of Shaanxi, China [ 6 , 7 ].…”