Separation of lithium isotopes with the N3O2 trimerrifield peptide resin

Abstract

A study on the separation of lithium isotopes was carried out with 1,13-dioxa-4,7,10-triazacyclopentadecane-4,7,10-trimerrifield peptide resin [N3023M ]. The resin having N302 as an anchor group has a capacity of 0.2 meq/g dry resin. Upon column chromatography [0.1 cm (I.D)x30 cm (height)] using 1.0M NHaCI solution as an eluent, a single separation factor of 1.00104 was obtained from the elution curve and isotope ratios based on the GLUECKAUF theory. The heavier isotope, 7Li concentrated in the resin phase, while the lighter isotope, 6Li enriched in the solution phase.

Novel Syntheses Method of Phenol Type Benzo-15-Crown-5 Ether Resin and its Application for Lithium Isotope Separation

“…While, Kim et al reported the contrary tendency of the lithium isotope enrichment by using the different crown ethers such as the 18-crown-6 7) and triazacrown. 8) This difference is interesting. The separation coefficients obtained by use of crown ether resins were summarized in Table 1.…”

“…The isotope exchange of metal elements on crown ether is expected to have the high separation coefficient in comparison to other chemical reaction. [1][2][3][4][5][6][7][8] The many isotope separation experiments based on complex formation of metal ions with crown ether were carried out using the liquid-liquid extraction 1,2) or the extraction chromatography. 3,4) The liquid-liquid extraction is difficult to commercially separate the isotopes, because the distribution coefficient is too small and the establishment of the multi-stage process is difficult.…”

Preparation and Characterization of Polysulfone-graft-4′-aminobenzo-15-crown-5-ether for Lithium Isotope Separation

“…The mercury amalgam method is the first industrial-scale application for lithium isotope separation. , However, the huge volumes of toxic mercury used in this technique bring about serious biological and environmental problems. To avoid the use of toxic mercury, many other techniques such as laser, , electromigration, − solvent extraction, − chromatography, − and membrane separation , have been developed. Among them, solvent extraction and chromatography methods using crown ethers or polymerized crown ethers as lithium isotope receptor have been proven to be an alternative method with favorable separation factor. ,, …”

Crown Ether Chemistry of Polydentate Complexing for Lithium Isotope Separation

“…1983 年, Fujine 等 [29] 首先使用商品化的穴醚 ( 采用类似的合成方法, 该课题组 [34] 合成了 N 4 O 2 氮 杂冠醚树脂 20, N 4 O 2 枝接量为 3.8 meq/g, 可得 1.038 的 同位素单级分离系数; N 4 S 2 硫氮杂冠醚树脂 21, N 4 S 2 枝 接量为 0.34 meq/g, 可得 1.034 的同位素单级分离系 数 [35] ; 对于 N 4 O 氮杂冠醚树脂 22 [36] 以及 N 3 O 2 氮杂冠醚 树脂 23 [37] , 则分别只有 1.00127 及 1.00104 的同位素分 离系数.…”