scholarly journals SIMS analyses of rare earth elements in natural minerals and glasses: An investigation of structural matrix effects on ion yields

Scanning ◽  
1992 ◽  
Vol 14 (3) ◽  
pp. 160-168 ◽  
Author(s):  
Piero Bottazzi ◽  
Luisa Ottolini ◽  
Riccardo Vannucci
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Matrix Effects ◽  
Natural Minerals ◽  
Ion Yields ◽  
Structural Matrix

Rare-Earth Analysis by a Rotating Platform, Silver-Spark Technique

1968 ◽  
Vol 22 (5) ◽  
pp. 558-561
Author(s):  
Theodore R. Lyon
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Electrode Material ◽  
Matrix Effects ◽  
Small Samples ◽  
Good Sensitivity ◽  
Rotating Platform

A rotating platform, silver-spark technique has been adapted for analysis of rare-earth elements directly, either as solutions or after coprecipitation with a carrier. The platform sample electrode is compared with the rod sample electrode conventionally used, and silver is shown to provide some advantages over copper as an electrode material. Observations are reported on conditions pertaining to the preparation and excitation of samples. Three varied applications of the method are briefly described, and matrix effects are discussed. Platform electrodes are found to be more convenient and adaptable than conventional rods, and the sensitivity of the method is comparable to the copper-spark method for small samples. When larger samples are used, the sensitivity decreases; however, good sensitivity can be obtained by properly selecting conditions or equipment.

scholarly journals Detection of Rare Earth Elements in Minerals and Soils by Laser-Induced Breakdown Spectroscopy (LIBS) Using Interval PLS

Minerals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1379
Author(s):  
Nina Rethfeldt ◽  
Pia Brinkmann ◽  
Daniel Riebe ◽  
Toralf Beitz ◽  
Nicole Köllner ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Matrix Effects ◽  
Principal Component ◽  
Laser Induced Breakdown Spectroscopy ◽  
Regression Methods ◽  
Breakdown Spectroscopy ◽  
Field Samples ◽  
Laser Induced Breakdown

The numerous applications of rare earth elements (REE) has lead to a growing global demand and to the search for new REE deposits. One promising technique for exploration of these deposits is laser-induced breakdown spectroscopy (LIBS). Among a number of advantages of the technique is the possibility to perform on-site measurements without sample preparation. Since the exploration of a deposit is based on the analysis of various geological compartments of the surrounding area, REE-bearing rock and soil samples were analyzed in this work. The field samples are from three European REE deposits in Sweden and Norway. The focus is on the REE cerium, lanthanum, neodymium and yttrium. Two different approaches of data analysis were used for the evaluation. The first approach is univariate regression (UVR). While this approach was successful for the analysis of synthetic REE samples, the quantitative analysis of field samples from different sites was influenced by matrix effects. Principal component analysis (PCA) can be used to determine the origin of the samples from the three deposits. The second approach is based on multivariate regression methods, in particular interval PLS (iPLS) regression. In comparison to UVR, this method is better suited for the determination of REE contents in heterogeneous field samples.

A Combined Dilution and Line-Overlap Coefficient Solution for the Determination of Rare Earths in Monazite Concentrates

1981 ◽  
Vol 25 ◽  
pp. 133-137
Author(s):  
T. K. Smith
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Atomic Number ◽  
Rare Earths ◽  
Microprobe Analysis ◽  
Matrix Effects ◽  
Emission Spectra ◽  
X Ray ◽  
Overlap Coefficient

The rare earth elements (REE) together give guite complex X-ray emission spectra with a considerable number of overlaps at analytical energies by lines of other REE with lower atomic numbers. Where the concentration of REE is high, as in lanthanide minerals, this Interference is more difficult to rectify. Smith and Gold resolved a similar problem with lower atomic number elements in energy dispersive microprobe analysis by establishing a series of overlap coefficients. They asserted that accurate corrections were necessary because of the relatively poor overall resolution of the instrument and that these should not be limited to the major coincidences. Some of the smaller values had probably been ignored because they were considered statistically Insignificant. The mathematical matrix of Smith and Gold covered 22 elements from fluorine to barium, with intensity coefficients (other than intraelement) quoted from 0.01% to 282.1% and with ZAF corrections necessary in cases of K to L conversion. The overlap coefficients were also adjusted for matrix effects.

scholarly journals Bioleaching of Phosphate Minerals Using Aspergillus niger: Recovery of Copper and Rare Earth Elements

Metals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 978
Author(s):  
Laura Castro ◽  
Maria Luisa Blázquez ◽  
Felisa González ◽  
Jesús Angel Muñoz
Keyword(s):  
Rare Earth ◽  
Aspergillus Niger ◽  
Rare Earth Elements ◽  
Aluminum Phosphate ◽  
Soluble Form ◽  
Copper Ore ◽  
Batch Cultures ◽  
Cerium Phosphate ◽  
Natural Minerals ◽  
Phosphate Solubilizing

Rare earth elements (REE) are essential in high-technology and environmental applications, where their importance and demand have grown enormously over the past decades. Many lanthanide and actinide minerals in nature are phosphates. Minerals like monazite occur in small concentrations in common rocks that resist weathering. Turquoise is a hydrous phosphate of copper and aluminum scarcely studied as copper ore. Phosphate-solubilizing microorganisms are able to transform insoluble phosphate into a more soluble form which directly and/or indirectly contributes to their metabolism. In this study, bioleaching of heavy metals from phosphate minerals by using the fungus Aspergillus niger was investigated. Bioleaching experiments were examined in batch cultures with different mineral phosphates: aluminum phosphate (commercial), turquoise, and monazite (natural minerals). The experiments were performed at 1% pulp density and the phosphorous leaching yield was aluminum phosphate > turquoise > monazite. Bioleaching experiments with turquoise showed that A. niger was able to reach 8.81 mg/l of copper in the aqueous phase. Furthermore, the fungus dissolved the aluminum cerium phosphate hydroxide in monazite, reaching up to 1.37 mg/L of REE when the fungus was grown with the mineral as the sole phosphorous source. Furthermore, A. niger is involved in the formation of secondary minerals, such as copper and REE oxalates.

Sign in / Sign up

Export Citation Format

Share Document