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Title: Towards resolving the Rare Earth Crisis: Acquiring thermodynamic data required for modelling of the formation of Th-bearing monazites

Abstract

This report describes the Rare Earth Crisis and the effect of rare earth elements.

Authors:
 [1];  [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1392887
Report Number(s):
LA-UR-17-28442
TRN: US1800046
DOE Contract Number:
AC52-06NA25396
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; RARE EARTHS; MONAZITES; THERMODYNAMICS; THORIUM; hydrothermal; REE; Th; fractionation

Citation Formats

Migdissov, Artaches, and Nisbet, Haylea Dawn. Towards resolving the Rare Earth Crisis: Acquiring thermodynamic data required for modelling of the formation of Th-bearing monazites. United States: N. p., 2017. Web. doi:10.2172/1392887.
Migdissov, Artaches, & Nisbet, Haylea Dawn. Towards resolving the Rare Earth Crisis: Acquiring thermodynamic data required for modelling of the formation of Th-bearing monazites. United States. doi:10.2172/1392887.
Migdissov, Artaches, and Nisbet, Haylea Dawn. 2017. "Towards resolving the Rare Earth Crisis: Acquiring thermodynamic data required for modelling of the formation of Th-bearing monazites". United States. doi:10.2172/1392887. https://www.osti.gov/servlets/purl/1392887.
@article{osti_1392887,
title = {Towards resolving the Rare Earth Crisis: Acquiring thermodynamic data required for modelling of the formation of Th-bearing monazites},
author = {Migdissov, Artaches and Nisbet, Haylea Dawn},
abstractNote = {This report describes the Rare Earth Crisis and the effect of rare earth elements.},
doi = {10.2172/1392887},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 9
}

Technical Report:

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  • In 1984 and 1985 the Bureau of Mines investigated radioactive carbonate veins near Salmon Bay, southeastern Alaska, for concentrations of columbium and associated metals. The veins cut units of graywacke, conglomerate, argillite, and limestone and range in width from less than an inch to greater than 10 ft and have a length ranging from less than a hundred to greater than 1,000 ft. Mineralogy of the veins is complex, and includes thorite, the rare-earth-element minerals monazite, parisite, and bastnaesite, and a columbium mineral that is speculated to be columbite. Gangue minerals include ankerite, dolomite, siderite, quartz and albite. More thanmore » seventy veins were sampled but only three contain elevated metal concentrations along a significant strike length. These resources are small compared to columbium, REE, and thorium resources elsewhere in the world.« less
  • The extraction of stable isotopes of Eu and Ce was investigated from simulated sodium-bearing waste (SBW) and dissolved zirconium calcine by TRUEX and CMP solvents at the Idaho Chemical Processing Plant (ICPP). Single batch contacts were carried out in order to evaluate the rare earth behavior in the extraction, scrub, strip and wash sections for the proposed flowsheets. It has been shown that these lanthanides are efficiently extracted from the sodium-bearing wastes into either solvent, are not scrubbed and are stripped from both of the extractants with dilute HEDPA. The extraction distribution coefficients for Ce and Eu are higher inmore » the TRUEX solvent (D{sub Ce} = 11.7, D{sub Eu} = 14.9) compared with CMP (D{sub Ce} = 9.3, D{sub Eu} = 7.23) for SBW. The extraction distribution coefficients for Ce and Eu are considerably less in the TRUEX solvent (D{sub Ce}=1.13, D{sub Eu}=1.8) than in the CMP solvent (D{sub Ce}=7.4, D{sub Eu=}6.1) for dissolved zirconium calcine feeds. The lower distribution coefficients for the extraction of lanthanides in the TRUEX/dissolved zirconium calcine system can be explained by zirconium loading of the solvent. The data obtained also confirmed that Ce and Eu can be used as non-radioactive surrogates for Am in separation experiments with acidic solutions.« less
  • A variety of thorium- and rare-earth-bearing minerals occurs in South Africa, but most of the deposits are too small to assume economic significance. At present the only mineral which is beirg produced primarily for rare earths and thorium is monazite from a lode deposit in the western Cape Province. Pegmatite resources are largely untapped. Much of the base mineral content has already been disposed of, but up to the present there has been no demand for the radioactive or rare-earth-bearing minerals. Apart from the minerals available from this source, bastuaesite, calciumyttrium silicate, allanite, and urimothorianite could be profitably produced frommore » the Union should the demand for thorium and rare earths improve. (auth)« less
  • The heat capacities of 8 rare earth sesquioxides were measured over the range from 10 to 350 deg K. The sesquioxides of lanthanum and neodymium possessed an isomorphic hexagonal structure, samarium sesquioxide the Btype structure, and of the sesquioxides known to crystallize in the cubic phase, those of gadolinium, dysprosium, holmium, erbium, and ytterbium were determined. The lattice heat capacity of the hexagonal structures was approximated by the heat capacity of lanthanum sesquioxide and that for the isomorphic cubic structures below 100 deg K from the heat capacity of ytterbium oxide and above 100 deg K from the heat capacitymore » of gadolinium oxide. Therefore the magnetic heat capacities of the sesquioxides of neodymium, gadolinium, dysprosium, holmium, erbium, and ytterbium were resolved from the knowledge of their isomorphic lattice heat capacities. The magnetic heat capacities above 10 deg K are characterized by Schottky anomalies which were correlated to the energy levels created by the crystalline stances studied were H/sub 2/IrCl/sub 6/, K/sub 2/IrCl/sub 6/, K/sub 3/IrCl/sub 6/ - H/sub 2/O , and tration. With this polarograpbic technique, Ir can be purities. (D.L.C.) Differences between proton and hydride transfers are hibits CH and OH isotope effects of 2.94 and 1.49. These transfer from oxygen. (auth) >i in the decarboxylation of substituted benzolacetic acids in benzene at 50 deg are 2.8 for m-nitro, 1.7 for p-chloro, 1.4 for unsubstituted, and 0.85 for p- methyl, although these substituents have a negligible effect on OH frequencies in the ground state. This large variation in isotope effect with substituents is inconsistent with a cyclic hydride transfer mechanism but in accord with a cyclic proton transfer mechanism. (auth)« less
  • Continuation of studies on the phase relationships and the physical, thermodynamic, and high-temperature properties of oxide and nitride systems of the transition metals is reported. Equilibrium pressure measurements and x-ray diffraction, differential thermal anulysis, and thermogravimetric analysis are among the methods being used. Work in progress during the report period was centered around a study of oxidation kinetics of lanthanum, cerium, praseodymium, neodymium, samarium, gadolinium, and ytterbium. Results are tabulated on aspects such as the temperature region in which an activation energy was observed, the rate laws which were obeyed, activation energies, effects of reducing oxygen partial pressures, and effectsmore » on inert atmospheres. Preparations for studies of phases produced in the region between rare earth metals and their nitrides are reported. Data are also included on the infrared spectra of rare earth hydroxides, and onides which provide information on the type and intensity of the hydroxide bonding. A study of kinetics in high vacuum reduction or decomposition of mixed rare earth oxides is also being made. Preliminary investigations are being conducted to select the mixing agent from among ytterbium, erbium, and lutetium oxides. Papers for publication on the oxidation kinetics of cerium and lanthanum are included. (J.R.D.)« less