Hafnium is een glanzend en buigzaam metaal met uitstekende corrosiebestendigheid. Chemisch gezien vertoont het veel overeenkomsten met zirkonium en daardoor zijn deze elementen moeilijk van elkaar te onderscheiden. Het opmerkelijkste verschil is de dichtheid; die van hafnium …
17-1-2019· The preparation of nuclear-grade zirconium and hafnium is very important for nuclear power. The separation of hafnium from zirconium in a hydrochloric acid solution by solvent extraction was investigated with di(2-ethylhexyl)phosphoric acid (D2EHPA). The effects of hydrochloric acid concentration, extractant concentration, diluents, and temperature on the distribution coefficient of hafnium ...
18-6-2020· @article{osti_4011738, title = {PROCESS FOR THE SEPARATION AND PURIFICATION OF ZIRCONIUM AND HAFNIUM}, author = {Peters, K}, abstractNote = {A process for the separation and purification of hafnium and zirconium by means of complex compounds is described. The process consists of first treating freshly prepared zirconium - hafnium phosphates or hydroxides with …
Electrical properties of yttrium-doped hafnium-zirconium dioxide thin films prepared by solution process for ferroelectric gate insulator TFT application Mohit*, Ken-ichi Haga, and Eisuke Tokumitsu School of Materials Science, Japan Advanced Institute of Science and Technology (JAIST), Nomi, Ishikawa 923-1211, Japan *E-mail: [email protected]
Separation of Hafnium From Zirconium by Anion Exchange John 1. Hague and Lawrence A. Machlan (September 13, 1960) The resul ts of a systematic survey of the elution of hafnium and zirconium in diluted sulfuric acid, and i!1 solutions of hydrochloric and sulfuric acids in water, are presented.
The difficulties encountered in separating hafnium from zirconium are well known [6, 7].1 It has been shown [1] that a separation of hafnium and zirconium can be obtained by anion-exchange in sulfuric acid solution. The method described here has been used to determine hafnium and zirconium …
A process is provided for separating zirconium and hafnium tetrachlorides by the direct distillation from their solution in an eutectic mixture of sodium and potassium chlorides. Hafnium tetrachloride and zirconium tetrachloride are provided in adequate purity for direct introduction into reduction units for the production of the respective metals by virtue of controlled ratios of the salt ...
26-8-2019· Among transition metal carbides and nitrides, zirconium, and hafnium compounds are the most stable and have the highest melting temperatures. Here we review published data on phases and phase equilibria in Hf-Zr-C-N-O system, from experiment and ab initio computations with focus on rocksalt Zr and Hf carbides and nitrides, their solid solutions and oxygen solubility limits.
1-12-2014· The stripping of zirconium and hafnium from loaded LIX 63 containing 0.137 g/L of Zr and 0.02 g/L of Hf was carried out by varying the concentration of H 2 SO 4 and HCl solutions. The effect of the stripping agent concentration on the stripping percentage of zirconium and hafnium …
Hafnium is a shiny, silvery, ductile metal that is corrosion-resistant and chemically similar to zirconium (due to its having the same number of valence electrons, being in the same group, but also to relativistic effects; the expected expansion of atomic radii from period 5 to 6 is almost exactly cancelled out by the lanthanide contraction). Hafnium changes from its alpha form, a hexagonal close-packed lattice, to its beta form, a body-centered cubic lattice, at 2388 K. The physical properties of hafnium metal samples are markedly …
Pilot plant extraction of hafnium from zirconium. of hafnium and zirconium occurs. Extraction section. The stages in which the aqueous volume consists of the scrub and feed volumes. The organic solvent enters the extraction section and the raffinate stream leaves the extraction section. Peed. An aqueous solution of hafnium and zirconium ...
(2020). Liquid–liquid separation of zirconium and hafnium from nitric liquor in order to obtain nuclear zirconium oxide using TBP as extractant. Chemical Engineering …
Zirconium is a chemical element with the symbol Zr and atomic number 40. The name zirconium is taken from the name of the mineral zircon (the word is related to Persian zargun (zircon; zar-gun, "gold-like" or "as gold")), the most important source of zirconium. It is a lustrous, grey-white, strong transition metal that closely resembles hafnium and, to a lesser extent, titanium.
The zirconium and hafnium separation schematic technology diagram with extraction, washing and re-extraction stages was offered. At the first stage zirconium is extracted by tributylphosphate solution. The received organic phase is washed by solution containing 0.1–0.5 mole/dm3 of HNO3 with phases proportionate as O:W = 7:1.
Zirconium and hafnium are extracted quantitatively into chloroform, dichloroethane or nitrobenzene in the presence of hexyl-, nonyl- and o-nitrophenyl diantipyrylmethane from hydrochloric acid solutions (⩾ 8 M) in the form of RMeCl 4,complexes.New methods of determining up to 1·10 −4 % zirconium in materials containing Mg, Be, Al, Y, Sc, La, Ce, Ti, Th, Cr, Ni, and other elements are ...
zirconium carbonate acid solution precipitate Prior art date 1940-07-17 Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.) Expired - Lifetime Application number US346059A Inventor Wainer Eugene
For the separation of hafnium from zirconium, a CuCl2-containing molten chloride salt is used to selectively extract hafnium in the zirconium produced in the electrolysis step.
1-12-2014· The stripping of zirconium and hafnium from loaded LIX 63 containing 0.137 g/L of Zr and 0.02 g/L of Hf was carried out by varying the concentration of H 2 SO 4 and HCl solutions. The effect of the stripping agent concentration on the stripping percentage of zirconium and hafnium …
L. Poriel et al, “Zirconium and Hafnium Separation, Part 2. Solid/liquid Extraction in Hydrochloric Acid Aqueous Solution with Anion Exchange Resins”, Separation Science and Technology, 41 (2006), 2711–2722. CrossRef Google Scholar
This article is cited by 53 publications. Jason P. Holland. Predicting the Thermodynamic Stability of Zirconium Radiotracers.
This article is cited by 53 publications. Jason P. Holland. Predicting the Thermodynamic Stability of Zirconium Radiotracers.
The zirconium and hafnium separation schematic technology diagram with extraction, washing and re-extraction stages was offered. At the first stage zirconium is extracted by tributylphosphate solution. The received organic phase is washed by solution containing 0.1–0.5 mole/dm3 of HNO3 with phases proportionate as O:W = 7:1.
The preparation of nuclear-grade zirconium and hafnium is very important for nuclear power. The separation of hafnium from zirconium in a hydrochloric acid solution by solvent extraction was ...
OSTI.GOV Journal Article: Electrometric Titrations of Zirconium and Hafnium Solutions. Electrometric Titrations of Zirconium and Hafnium Solutions. Full Record; Other Related Research; Authors: Larsen, E M; Gammill, A M Publication Date: Tue Aug 01 00:00:00 EDT 1950 Research Org.:
zirconium hafnium solution. Separation of Hafnium from Zirconium and Their ... Separation of Hafnium from Zirconium and Their Deter ... 3 Each column must be calibrated to determine the volume of solution needed to elute the hafnium and zirconium.
This article shows the investigation of peculiarities of preparation and stability of concentrated solutions of zirconium (hafnium) nitrates, containing 100–350 g/dm3 of zirconium (hafnium) and 2–6 mol/dm3 of nitric acid. There were found the optimum conditions of concentrated nitrate solutions preparation, using initial zirconium (hafnium) salt processing by sodium or ammonium hydroxide ...
of Zr and Hf would yield a solution concentration of 1.096E-05 M and 6.72E-06 M, respectively. The concen-tration of dissolved Zr (or Hf) in solution was calculated as a function of pH. Speciation diagrams for zirconium and hafnium in aqueous solutions were also constructed for the same total amount of Zr and Hf as those used for solubility ...
The sorption properties of zirconium and hafnium toward a commercial macroporous anion exchanger (Amberjet 4200 Cl) in acidic chloride solutions were investigated. Variations of the distribution ratio, as a function of HCl concentration in the range of 0.1−12 M, were studied. Separation factors up to 9, under equilibrium conditions, were obtained with an HCl concentration of 9.5 M ...
zirconium and hafnium solution is passed through a series of liquid-liquid extractions, stripping, and scrubbing steps to separate zirconium from hafnium. Liquid-liquid extraction, using methyl isobutyl ketone (containing thi ocyanate) as a solvent, separates zirconium from hafnium by preferentially extracting hafnium into the solvent phase.
The mononitrides of hafnium and zirconium of stoi-chiometry MN (M ) Hf, Zr) are all metallic conductors.1 On the other hand, the higher nitrides of hafnium and zirconium, M 3N 4, are reported to be transparent insula-tors or semiconductors.2-11 In general, the properties of group IV nitrides are well-understood for nitrogen-
