Extraction of Rare Earth from La–Ni Alloys by the Glass Slag Method

2003 ◽  
Vol 18 (12) ◽  
pp. 2814-2819 ◽  
Author(s):  
Tetsuji Saito ◽  
Hironori Sato ◽  
Tetsuichi Motegi
Keyword(s):  
Rare Earth ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Oxide Phase ◽  
Chemical Analyses ◽  
X Ray Diffraction ◽  
X Ray ◽  
Boron Trioxide ◽  
Ni Alloys

The use of the glass slag method in the extraction of rare earth from La–Ni alloys was studied. X-ray diffraction and electron probe microanalysis studies revealed that the La–Ni alloys produced by the glass slag method using boron trioxide consisted of Ni and Ni3B phases. No La-containing phase such as the LaNi5 phase and the La oxide phase was found in the resultant alloys. The chemical analyses confirmed that the La content in the alloys produced by the glass slag method was very limited. However, the glass slag materials contained a large amount of lanthanum. The La in the La–Ni alloys was successfully extracted by the glass slag method using boron trioxide.

Chemical variability in wakabayashilite: a real feature or an analytical artifact?

2014 ◽  
Vol 78 (3) ◽  
pp. 693-702 ◽  
Author(s):  
L. Bindi ◽  
P. Bonazzi ◽  
M. Zoppi ◽  
P. G. Spry
Keyword(s):  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Chemical Analyses ◽  
X Ray Diffraction ◽  
Wavelength Dispersive Spectroscopy ◽  
X Ray ◽  
Minor Elements ◽  
Molecular Group ◽  
Chemical Variability

AbstractWakabayashilite is a rare mineral with ideal formula [(As,Sb)6S9][As4S5]. Its structure consists of an [M6S9] bundle-like unit (M = As, Sb) running along the [001] axis and [As4S5] cage-like molecules. In this study, samples of wakabayashilite from different occurrences (Khaidarkan, Kyrgyzstan; Jas Roux, France; White Caps mine, USA; Nishinomaki mine, Japan) were selected to verify the possible presence of different molecular groups replacing the As4S5 molecule. Given the chemical (electron probe microanalysis-wavelength dispersive spectroscopy), spectroscopic (micro-Raman) and structural (single-crystal X-ray diffraction) results obtained, it appears evident that only the As4S5 molecular group is present in the wakabayashilite structure and that the apparent non-stoichiometry reported in literature is actually due to unreliable chemical analyses. The structural role of the minor elements (Cu, Zn and Tl) in wakabayashilite is also discussed.

scholarly journals Syntheses, crystal structures, and comparisons of rare-earth oxyapatites Ca2 RE 8(SiO4)6O2 (RE = La, Nd, Sm, Eu, or Yb) and NaLa9(SiO4)6O2

2019 ◽  
Vol 75 (7) ◽  
pp. 1020-1025 ◽  
Author(s):  
Jarrod V. Crum ◽  
Saehwa Chong ◽  
Jacob A. Peterson ◽  
Brian J. Riley
Keyword(s):  
Rare Earth ◽  
Crystal Structures ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Similar Unit ◽  
Cell Volumes

Six different rare-earth oxyapatites, including Ca2 RE 8(SiO4)6O2 (RE = La, Nd, Sm, Eu, or Yb) and NaLa9(SiO4)6O2, were synthesized using solution-based processes followed by cold pressing and sintering. The crystal structures of the synthesized oxyapatites were determined from powder X-ray diffraction (P-XRD) and their chemistries verified with electron probe microanalysis (EPMA). All the oxyapatites were isostructural within the hexagonal space group P63/m and showed similar unit-cell parameters. The isolated [SiO4]4− tetrahedra in each crystal are linked by the cations at the 4f and 6h sites occupied by RE 3+ and Ca2+ in Ca2 RE 8(SiO4)6O2 or La3+ and Na+ in NaLa9(SiO4)6O2. The lattice parameters, cell volumes, and densities of the synthesized oxyapatites fit well to the trendlines calculated from literature values.

A note on the occurrence of chevkinite, allanite, and zirkelite on St. Kilda, Scotland

1982 ◽  
Vol 46 (341) ◽  
pp. 445-448 ◽  
Author(s):  
R. R. Harding ◽  
R. J. Merriman ◽  
P. H. A. Nancarrow
Keyword(s):  
Rare Earth ◽  
Great Britain ◽  
Electron Probe ◽  
Energy Dispersive ◽  
X Ray Diffraction ◽  
Electron Probe Analysis ◽  
Accessory Minerals ◽  
X Ray ◽  
Probe Analysis ◽  
Recorded Occurrence

AbstractThe occurrence of three accessory minerals with significant rare earth contents in Tertiary acid rocks of St. Kilda is described. Allanite, zirkelite, and chevkinite were identified by electron probe analysis (with energy-dispersive attachment) and the chevkinite confirmed by X-ray diffraction. Brief comparison is made with other Tertiary occurrences of RE minerals. This is the first recorded occurrence of chevkinite in Great Britain.

New insights into the nature of glauconite

2020 ◽  
Vol 105 (5) ◽  
pp. 674-686 ◽  
Author(s):  
Adrián López-Quirós ◽  
Antonio Sánchez-Navas ◽  
Fernando Nieto ◽  
Carlota Escutia
Keyword(s):  
Electron Probe ◽  
Layer Growth ◽  
Chemical Characteristics ◽  
Chemical Analyses ◽  
X Ray Diffraction ◽  
K Uptake ◽  
X Ray ◽  
New Findings ◽  
Dioctahedral Mica ◽  
Interstratified Mineral

Abstract Glauconite must be assessed as mica-rich mica-smectite R3 interstratified mineral, with the pure end-member mica also having intrinsic K-deficient chemical characteristics (K+ ~ 0.8 apfu). This assertion is in accordance with our X-ray diffraction (XRD) and high-resolution tranmission electron microscopy (HRTEM) studies and chemical analyses by electron probe microanalysis (EPMA) of mature glauconites in Cenozoic Antarctic sediments that indicate that: (1) It consists of a glauconite-smectite (R3 ordered) mixed-layer silicate, composed mainly of mica-type layers (>90%), but displaying slightly different proportions of Fe(III)-smectite layers (<10%). (2) More mature glaucony grains are characterized by major K+ and VIFe2+ (mica layers) and minor VIFe3+ (smectite layers) content in the interstratified glauconite-smectite. (3) Potassium is stabilized at the interlayer site by the octahedrally coordinated Fe2+. (4) Microtexture of the glauconite crystals are comparable with those of other micas and illite minerals, with straight, defect-free lattice fringes of ~10 Å spacings glauconite packets characteristic of mica with minor interstratified poorly crystalline smectite layers. In addition, our new findings give insights into the glauconitization process and at the same time investigate the potassium-deficient character of the dioctahedral mica “glauconite.” These findings show that glauconite crystallizes by a layer-growth mechanism at the expense of a poorly crystalline smectite precursor and that smectiteto-glauconite transformations are accompanied by a gradually higher octahedral charge deficiency (Fe2+/Fe3+) stabilized by K+ uptake into the interlayer sheet.

Synthetic TRPO4 crystals as reference samples in the quantitative X-ray electron probe microanalysis of rare-earth elements

2011 ◽  
Vol 66 (9) ◽  
pp. 831-837 ◽  
Author(s):  
Yu. G. Lavrent’ev ◽  
I. M. Romanenko ◽  
M. P. Novikov ◽  
L. V. Usova ◽  
V. N. Korolyuk
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
X Ray ◽  
Reference Samples

Rare-earth element determination in minerals by electron-probe microanalysis: application of spectrum synthesis

1998 ◽  
Vol 62 (1) ◽  
pp. 1-8 ◽  
Author(s):  
S. J. B. Reed ◽  
A. Buckley
Keyword(s):  
Rare Earth ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Distribution Patterns ◽  
Correction Factors ◽  
Relative Precision ◽  
Element Determination ◽  
X Ray ◽  
Background Measurement ◽  
Spectrum Synthesis

AbstractElectron-probe microanalysis (EPMA) is applicable to rare-earth elements (REE) in minerals with relatively high REE concentrations (e.g. hundreds of parts per million). However, given that each of the 14 REE has at least 12 X-ray lines in the L spectrum, finding peak-free regions for background measurement can be problematical. Also, measured peak intensities are liable to require correction for interferences. Hitherto, little attention has been paid to the optimisation of background offsets and the implications of the wide variation in REE distribution patterns in different minerals. The ‘Virtual WDS’ program, which enables complex multi-element spectra to be synthesised, has been used to refine the conditions used for different REE distributions. Choices include whether to use the Lβ1 rather than the Lα1 line, background offsets, and counting times for comparable relative precision. Correction factors for interferences affecting peak and background measurements have also been derived.

Ba3YRu0.73(2)Al1.27(2)O8 and Ba5Y2Ru1.52(2)Al1.47(2)O13.5: New Perovskite Ruthenates with Partial Octahedra Replacement

2007 ◽  
Vol 62 (11) ◽  
pp. 1383-1389 ◽  
Author(s):  
Barbara Schüpp-Niewaa ◽  
Larysa Shlyk ◽  
Yurii Prots ◽  
Gernot Krabbes ◽  
Rainer Niewa
Keyword(s):  
Single Crystal ◽  
Single Crystals ◽  
Diffraction Data ◽  
Electron Probe Microanalysis ◽  
Perovskite Structure ◽  
Electron Probe ◽  
X Ray Diffraction ◽  
Powder Mixtures ◽  
X Ray ◽  
Vertex Sharing

Dark red single crystals of the new phases Ba3YRu0.73(2)Al1.27(2)O8 and Ba5Y2Ru1.52(2)Al1.47(2)O13.5 have been grown from powder mixtures of BaCO3, Y2O3, Al2O3, and RuO2 . The compositions given in the formulas result from the refinements of the crystal structures based on single crystal X-ray diffraction data (hexagonal P63/mmc (No. 194), Z = 2, Ba3 YRu0.73(2)Al1.27(2)O8: a = 5.871(1), c = 14.633(3) Å , R1 = 0.035, wR2 = 0.069 and Ba5Y2Ru1.52(2)Al1.47(2)O13.5: a = 5.907(1), c = 24.556(5) Å, R1 = 0.057, wR2 = 0.114). Ba3YRu0.73(2)Al1.27(2)O8 crystallizes in a 6H perovskite structure, Ba5Y2Ru1.52(2)Al1.47(2)O13.5 has been characterized as a 10H Perovskite. Due to similar spatial extensions of (Ru2O9) facesharing pairs of octahedra and (Al2O7) vertex-sharing pairs of tetrahedra, both structures show partial mutual substitution of these units. Consequently, the title compounds may be written as Ba3Y(Ru2O9)1−x(Al2O7)x, x = 0.64(1) and Ba5Y2RuO6(Ru2O9)1−x(Al2O7)x, x = 0.74(1). This interpretation is supported by the results of electron probe microanalysis using wavelength-dispersive X-ray spectroscopy. An oxidation state of Ru close to +5 for the (Ru2O9) units, as can be derived from the distances d(Ru-Ru), additionally leads to similar charges of both the (Ru2O9) and the (Al2O7) units.

An investigation of the invariant reactions in the BiPbSrCaCuO system

1996 ◽  
Vol 11 (9) ◽  
pp. 2142-2151 ◽  
Author(s):  
Libin Liu ◽  
Zhanpeng Jin
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Invariant Reaction ◽  
Reaction Scheme ◽  
Partial Substitution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Melting Temperatures

The phases present around the (Bi, Pb)2Sr2Ca2Cu3Ox (2223) phase between 830–880 °C have been studied by x-ray diffraction (XRD) and electron probe microanalysis (EPMA) methods. The decomposition and melting temperatures of the 2223 phase in these samples have been measured by the differential thermal analysis (DTA) method. Partial substitution of Bi with Pb (Pb: Bi = 3: 22) does not change the 850 °C phase relations around 2223 phase. 2223 decomposes to liquid, Sr7Ca7Cu24O41 (7724), and Ca2CuO3 at 875 °C. The invariant reactions (degree of freedom is zero) among 2223, 7724, Ca2CuO3, CuO, Bi2Sr2CaCu2O8 (2212), and liquid were proposed to be L + 7724 + Ca2CuO3 → 2223 + 2212, L + 7724 + Ca2CuO3 → 2223 + CuO, L + 7724 → 2223 + 2212 + CuO. The reaction temperatures were estimated to be 860 °C, 860 °C, and 854 °C, respectively. An invariant reaction scheme and a tentative liquidus projection were sketched out.

Thermoelectric Properties of InxCo4-yNiySb12 Skutterudite Compounds

2007 ◽  
Vol 1044 ◽  
Author(s):  
Veronique Da Ros ◽  
Juliusz Leszczynski ◽  
Bertrand Lenoir ◽  
Anne Dauscher ◽  
Christophe Candolfi ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Electrical Resistivity ◽  
Thermal Properties ◽  
Chemical Composition ◽  
Thermoelectric Power ◽  
Thermoelectric Properties ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
X Ray Diffraction ◽  
X Ray

AbstractThe preparation of partially filled n-type InxCo4Sb12 skutterudite compounds has been recently reported. The results were particularly promising, the materials exhibiting a ZT value far higher than one at moderated temperature. In this paper, we propose to investigate another way to tune the electrical and thermal properties by substituting Co atoms by Ni atoms in InxCo4Sb12. InxCo4-yNiySb12 polycrystalline samples have been prepared by a conventional metallurgical route. Structural analyses have been carried out by X-ray diffraction. The chemical composition and micro-homogeneity have been checked by electron probe microanalysis. Measurements of the electrical resistivity, thermoelectric power and thermal conductivity have been performed between 300 and 800 K. The influence of the presence of Ni on the thermoelectric properties of InxCo4Sb12 compounds is presented and discussed.

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