Resolving the structural state of heavy rare earth elements in lateritic ion adsorption clays

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F62156489%3A43410%2F19%3A43917211" target="_blank" >RIV/62156489:43410/19:43917211 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sga2019glasgow.com/abstract" target="_blank" >https://www.sga2019glasgow.com/abstract</a>

DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Resolving the structural state of heavy rare earth elements in lateritic ion adsorption clays

Popis výsledku v původním jazyce

Lateritic Ion Adsorption Deposits (IADs) are the world&apos;s dominant source for heavy rare earth elements (HREE: Gd-Lu), currently mostly mined from China. IADs in Brazil, Madagascar and South East Asia may provide alternative supply for HREE. However, the exact nature of REE in the IADs is unclear; for example whether deposits elsewhere are directly analogous to the easily-leachable Chinese laterites, and whether the REE are truly adsorbed, structurally bound in clays or hosted in other mineral phases. This study compares economically mineralized IADs from the Zhaibei granite, China to prospective IADs developed on peralkaline igneous rocks from Madagascar. We use synchrotron X-Ray Fluorescence (SXRF) element mapping and X-ray Absorption Spectroscopy (XAS) to study the distribution and coordination state of light and heavy REE. We explore sites of adsorption to clays and the presence of HREE in other mineral phases. The Malagasy and Chinese laterites have kaolinite as the dominant REE-hosting clay phase, with minor halloysite. XAS data demonstrate that the REE occur as 8 to 9-coordinated outer-sphere basal surface complexes on kaolinite, rather than 5- or 6-coordinated edge complexes, or 6- or 8-coordinated interlayer complexes, thus confirming the truly adsorbed nature of REE in lateritic IAD&apos;s from both localities.

Název v anglickém jazyce

Resolving the structural state of heavy rare earth elements in lateritic ion adsorption clays

Popis výsledku anglicky

Lateritic Ion Adsorption Deposits (IADs) are the world&apos;s dominant source for heavy rare earth elements (HREE: Gd-Lu), currently mostly mined from China. IADs in Brazil, Madagascar and South East Asia may provide alternative supply for HREE. However, the exact nature of REE in the IADs is unclear; for example whether deposits elsewhere are directly analogous to the easily-leachable Chinese laterites, and whether the REE are truly adsorbed, structurally bound in clays or hosted in other mineral phases. This study compares economically mineralized IADs from the Zhaibei granite, China to prospective IADs developed on peralkaline igneous rocks from Madagascar. We use synchrotron X-Ray Fluorescence (SXRF) element mapping and X-ray Absorption Spectroscopy (XAS) to study the distribution and coordination state of light and heavy REE. We explore sites of adsorption to clays and the presence of HREE in other mineral phases. The Malagasy and Chinese laterites have kaolinite as the dominant REE-hosting clay phase, with minor halloysite. XAS data demonstrate that the REE occur as 8 to 9-coordinated outer-sphere basal surface complexes on kaolinite, rather than 5- or 6-coordinated edge complexes, or 6- or 8-coordinated interlayer complexes, thus confirming the truly adsorbed nature of REE in lateritic IAD&apos;s from both localities.

Druh

D - Stať ve sborníku

CEP obor

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OECD FORD obor

10505 - Geology

Projekt

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Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Proceedings of the 15th SGA Biennial Meeting on Life with Ore Deposits on Earth. Volume 4

ISBN

978-0-85261-965-0

ISSN

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e-ISSN

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Počet stran výsledku

4

Strana od-do

1748-1751

Název nakladatele

University of Glasgow

Místo vydání

Glasgow

Místo konání akce

Glasgow

Datum konání akce

27. 8. 2019

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

000503111600457