Determination of the Mössbauer parameters of rare-earth nitroprussides: Evidence for new light-induced magnetic excited state (LIMES) in nitroprussides

The analytical capabilities of arc atomic emission determination of As, Bi, Sb, Cu, Te in rare earth metals (REM) and their oxides after preparatory group concentration using S,N-containing heterochain polymer sorbent are studied on a high-resolution spectrometer “Grand- Extra” (“WMC-Optoelectron-ics” company, Russia). Sorption kinetics and dependence of the degree of the impurity extraction on the solution acidity are analyzed to specify conditions of sorption concentration. To optimize the procedure of arc atomic emission determination of As, Bi, Sb, Cu, and Te various schemes of their sorption preconcentration and subsequent processing of the resulted concentrate with the addition of a collector at different stages of the sorption process have been considered. Graphite powder is used as a collector in analysis of rare earth oxides due to universality and relative simplicity of the emission spectrum. Conditions of analysis and parameters of the spectrometer that affect the analytical signal (mass and composition of the sample, shape and size of the electrodes, current intensity and generator operation mode, interelectrode spacing, wavelengths of the analytical lines) are chosen. The evaporation curves of the determinable impurities were studied and the exposure time of As, Bi, Sb, Cu, and Te in the resulted sorption concentrate was determined. Correctness of the obtained results was evaluated using standard samples of the composition and in comparisons between methods. The results of the study are used to develop a method of arc chemical-atomic emission analysis of yttrium, gadolinium, neodymium, europium, scandium and their oxides in a concentration range of n x (10-2 - 10-5) wt.%.

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DETERMINATION OF THE RARE EARTH METALS IN THE RED MUD FOR POSSIBLE UTILIZATION

Environmental Engineering and Management Journal ◽

10.30638/eemj.2018.199 ◽

2018 ◽

Vol 17 (8) ◽

pp. 2001-2009

Author(s):

Tatjana Juzsakova ◽

Akos Redey ◽

Le Phuoc Cuong ◽

Zsofia Kovacs ◽

Tamas Frater ◽

...

Keyword(s):

Rare Earth ◽

Red Mud ◽

Rare Earth Metals ◽

The Rare Earth

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USE OF A PORTABLE X-RAY FLUORESCENCE DETECTOR FOR DETERMINATION OF RARE EARTH ELEMENTS IN COAL BYPRODUCTS

10.1130/abs/2016am-286373 ◽

2016 ◽

Author(s):

Elliot Roth ◽

◽

Tracy L. Bank ◽

Emma Keegan ◽

Evan Granite

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Fluorescence Detector ◽

X Ray

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The fluorimetric determination of cerium and terbium

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19890616 ◽

1989 ◽

Vol 54 (3) ◽

pp. 616-621 ◽

Cited By ~ 3

Author(s):

Záviš Holzbecher

Keyword(s):

Rare Earth ◽

Detection Limit ◽

Rare Earth Elements ◽

Fluorimetric Determination ◽

Fluorescence Maximum ◽

Relative Standard ◽

And Shifts ◽

Hcl Medium ◽

Fold Excess

It has been found that phosphoric acid decreases the first excitation maximum of Ce(III) at 256 nm, increases the second excitation maximum at 297 nm and shifts the fluorescence maximum from 350 to 346 nm. Under optimum conditions, with λexc = 297 nm and λem = 346 nm, Ce(III) can be determined fluorimetrically with a detection limit of 1.2 ng ml-1 in 12M-H3PO4 medium. No interference was observed from a 20-200 fold excess of HCl, H2SO4, Na, K, NH4+, Al and the rare earth elements. HNO3 interferes and Ce(IV) and Fe(III) interfere strongly. It follows from the stereofluorograms of Ce and Tb that the spectra of the two elements are practically independent. The detection limit for Tb(III) in 0.02-2.5M-H2SO4 medium for λexc = 222 nm and λem = 494 nm is 33 ng ml-1. No interference was observed from a 5-20 fold excess of Al3+ and the other rare earth elements. The determination is slightly less sensitive in H3PO4 or HCl medium. The relative standard deviation of the measurement for 10 ng ml-1 Ce(III) or 50 ng ml-1 Tb(III) is about 3%.

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