Separation of lanthanides by capillary tube isotachophoresis using complex-forming equilibria

Nukatsuka, Isohi; Taga, Mitsuhiko; Yoshida, Hitoshi

doi:10.1016/s0021-9673(00)81817-8

Cited by 71 publications

(23 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure I 1 shows the observed and simulated isotachopherograms obtained at pHL=6. A good agreement was obtained in both cases when no Ca2+ was added (A) and ions utilizing the complex-forming effect has been reported for the lanthanides by Nukatsuka et al 58, in which a-hydroxyisobutyric acid (HIB) was used as the complex-forming agent. The concentration of a complex-forming agent and the pH of the leading electrolyte should be optimized in order to obtain good separation.…”

Section: Separation Utilizing the Complex-forming Effectsupporting

confidence: 74%

Computer Simulation of Isotachophoresis

Hirokawa

Kiso

1992

ANAL. SCI.

View full text Add to dashboard Cite

A computer simulation of isotachophoresis is described for the purpose of determining physico-chemical constants and separation optimization. On the basis of the mobilities, dissociation constants and stability constants of the separands, the effective mobilities and the isotachopherogram in the steady state condition can be exactly simulated at a given electrolyte condition. When some of the necessary constants are unknown, they can be evaluated by means of a leastsquares method on the basis of the observed qualitative indices. Since the sample amount necessary for electrophoretic separation is very small and good separability from coexisting substances is expected, this may be one of the useful methods for determining the physico-chemical constants. When the necessary constants are known, the optimum separation condition can be obtained by an iterative simulation that varies the electrolyte condition, such as the electrolyte pH, the solvent (water and methanol) and the concentration of the complex-forming agents to give the largest effective mobility differences among the separands.

show abstract

Section: Separation Utilizing the Complex-forming Effectsupporting

confidence: 74%

Computer Simulation of Isotachophoresis

Hirokawa

Kiso

1992

ANAL. SCI.

View full text Add to dashboard Cite

show abstract

“…25 cm V 21 s 21 from La 31 to Lu 31 -which is insufficient even when the most effective CE separation modes are used. Some additional mechanisms are necessary to amplify the differences in the effective mobilities of lanthanide ions and to facilitate their separation.…”

Section: Separation Modes and Strategiesmentioning

confidence: 99%

“…Probably the first electrophoretic method suitable for routine determinations of REEs was a capillary isotachophoretic method in an arrangement as suggested by Nakatsuka et al [31]. The ITP analysis was performed in the presence of HIBA as a constituent of leading electrolyte.…”

Section: Some Historical Factsmentioning

confidence: 99%

See 1 more Smart Citation

Analytical separations of lanthanides and actinides by capillary electrophoresis

Janoš

2003

Electrophoresis

View full text Add to dashboard Cite

The separation of lanthanide and actinide elements belongs to one of the most challenging tasks of the separation science, due to a great similarity in their physical and chemical properties. The electrophoretic separation can be accomplished in the presence of suitable complex-forming agents, from which alpha-hydroxyisobutyric acid (HIBA) has been used most often. In the most effective capillary electrophoretic mode--capillary zone electrophoresis (CZE)--a complete separation of lanthanide ions can be accomplished within a few minutes. Various electrophoretic methods can be relatively easily adopted for the determinations of individual lanthanide elements in certain kinds of technical materials, concentrates, precursors, etc., where the high speed and low costs of analysis characteristics of capillary electrophoresis (CE) may be advantageously exploited. Electrophoretic techniques may also be employed for speciation studies, especially for examinations of the behavior of actinides in the environment.

show abstract

“…The separation of fourteen lanthanide ions using the electrolyte is one of the typical applications of ITP. 5,6 However, since Y and Dy could not be separated by using the electrolyte, ITP was not useful for analyzing rareearth ores containing both Y and Dy. In order to improve this defect we have recently developed a new leading electrolyte by adding tartaric acid to the previous leading electrolyte as a helping complexing agent.…”

mentioning

confidence: 99%

Analysis of Some Rare-Earth Ores by the Isotachophoresis-Particle Induced X-Ray Emission Method

et al. 1994

View full text Add to dashboard Cite

Rare-earth ores (monazite, ion-adsorption type and xenotime) were analyzed using a coupled analytical method, isotachophoresis-particle induced X-ray emission (ITP-PIXE). The detection limit for each minor rare-earth element in the ores was ca. 0.01 mass% of the total rare-earth elements (TREE), when 200 µg of monazite was analyzed. Since yttrium was the major component in ion-adsorption type and xenotime ores, the use of a leading electrolyte containing a-hydroxyisobutyric acid and tartaric acid as complexing agents was effective for the separation of yttrium ion from lanthanide ions. KeywordsRare-earth element, isotachophoresis, particle induced X-ray emission (PIXE), isotachophoresis-PIXE The analysis of rare-earth ores, which include fourteen lanthanide elements and yttrium with very different abundances, is one of the difficult problems for any analytical method. Especially when the minor components in the ores are analyzed, an accurate analysis may be disturbed by inherent disadvantages of the employed method, for example, spectrum interference in atomic emission spectroscopy, isotope interference in mass spectroscopy and a matrix effect in X-ray analysis.In such instances chromatographic analysis may be useful. However, since the separation column used for analytical chromatography is easily overloaded, a large amount of sample can not be applied. Therefore, the detection method should be sufficiently sensitive to analyze minor components in the applied sample. As long as conventional detection methods are used, however, the necessary sensitivity is not always available. A coupled analytical method for rare-earth ores, HPLC-ICP-AES, as reported by Yoshida and Haraguchi', is one possible solution, where ICP-AES plays the role of an HPLC detector with high sensitivity and discriminating ability.On the basis of the same strategy, we have developed isotachophoresis-particle induced X-ray emission (ITP-P1XE). Ionic components in a sample solution are first preconcentrated and separated by ITP, and zones of the separated components are fractionated utilizing the counterflow of a leading electrolyte. Dropwise fractions are then analyzed off-line by PIXE. By using this coupled method, a crude rare-earth chloride from monazite ore2 and a model solution of high-level waste from the nuclear fuel cycle3,4 were analyzed with high accuracy.The leading electrolyte used contained a-hydroxyisobutyric acid (HIB) as the complex-forming agent. The separation of fourteen lanthanide ions using the electrolyte is one of the typical applications of ITP.5,6 However, since Y and Dy could not be separated by using the electrolyte, ITP was not useful for analyzing rareearth ores containing both Y and Dy. In order to improve this defect we have recently developed a new leading electrolyte by adding tartaric acid to the previous leading electrolyte as a helping complexing agent.' This paper aims to confirm the utility of the abovementioned electrolyte system in the analysis of rare-earth ores containing Y as one of the major component...

show abstract

Separation of lanthanides by capillary tube isotachophoresis using complex-forming equilibria

Cited by 71 publications

References 10 publications

Computer Simulation of Isotachophoresis

Computer Simulation of Isotachophoresis

Analytical separations of lanthanides and actinides by capillary electrophoresis

Analysis of Some Rare-Earth Ores by the Isotachophoresis-Particle Induced X-Ray Emission Method

Contact Info

Product

Resources

About