Chemical character and structure of uraniferous bitumens (Vrchlabí, Czech Republic)

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985891%3A_____%2F22%3A00566957" target="_blank" >RIV/67985891:_____/22:00566957 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/61389005:_____/22:00565001

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0166516222002130?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0166516222002130?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.coal.2022.104137" target="_blank" >10.1016/j.coal.2022.104137</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Chemical character and structure of uraniferous bitumens (Vrchlabí, Czech Republic)

Popis výsledku v původním jazyce

Black shales from the Permian rocks at Vrchlabí in the Krkonoše Piedmont Basin (Czech Republic) contain bitumens with uraninite grain inclusions and bulk uranium concentrations up to 4.8 wt%, determined by instrumental neutron activation analysis. The carbonaceous matter in the bitumens has been characterised by gas chromatography/mass spectrometry, attenuated total reflection Fourier transform infrared spectroscopy, scanning electron microscopy, and stable carbon isotopic composition. Progressive radiolytic alteration was documented by changes in the chemical composition and structure of both bulk samples and on the microscale. Condensation of aromatic structures, increase in content of oxygenated compounds, and enrichment in 13C were documented in the uranium-rich bulk samples. Micro-ATR-FTIR area mapping throughout the bright halos around uraninite inclusions revealed detailed structural changes, particularly a decrease in aliphatic bond intensities and an increase in the aromaticity of the structures close to the inclusions. A radiolytic alteration pathway has been suggested assuming a complex of reactions between organic matter and uranyl containing hydrothermal solutions, and oxidation by OH radicals produced in radiolysis of water. The organic matter transformations observed in the uraniferous bitumen correspond to the coalification processes, changing the bitumen composition from type I to type III and IV kerogens. Detailed characterisation of the radiation-induced chemical and structural changes in the naturally occurring uraniferous bitumens will contribute to the general understanding of the nature and behaviour of organic matter in other uraniferous environments or in the radioactive waste repositories.

Název v anglickém jazyce

Chemical character and structure of uraniferous bitumens (Vrchlabí, Czech Republic)

Popis výsledku anglicky

Black shales from the Permian rocks at Vrchlabí in the Krkonoše Piedmont Basin (Czech Republic) contain bitumens with uraninite grain inclusions and bulk uranium concentrations up to 4.8 wt%, determined by instrumental neutron activation analysis. The carbonaceous matter in the bitumens has been characterised by gas chromatography/mass spectrometry, attenuated total reflection Fourier transform infrared spectroscopy, scanning electron microscopy, and stable carbon isotopic composition. Progressive radiolytic alteration was documented by changes in the chemical composition and structure of both bulk samples and on the microscale. Condensation of aromatic structures, increase in content of oxygenated compounds, and enrichment in 13C were documented in the uranium-rich bulk samples. Micro-ATR-FTIR area mapping throughout the bright halos around uraninite inclusions revealed detailed structural changes, particularly a decrease in aliphatic bond intensities and an increase in the aromaticity of the structures close to the inclusions. A radiolytic alteration pathway has been suggested assuming a complex of reactions between organic matter and uranyl containing hydrothermal solutions, and oxidation by OH radicals produced in radiolysis of water. The organic matter transformations observed in the uraniferous bitumen correspond to the coalification processes, changing the bitumen composition from type I to type III and IV kerogens. Detailed characterisation of the radiation-induced chemical and structural changes in the naturally occurring uraniferous bitumens will contribute to the general understanding of the nature and behaviour of organic matter in other uraniferous environments or in the radioactive waste repositories.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

<a href="/cs/project/GA19-05360S" target="_blank" >GA19-05360S: Radiolytická alterace organické hmoty v uranonosném prostředí</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2022

Kód důvěrnosti údajů

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

Název periodika

International Journal of Coal Geology

ISSN

0166-5162

e-ISSN

1872-7840

Svazek periodika

264

Číslo periodika v rámci svazku

DEC 1

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

13

Strana od-do

104137

Kód UT WoS článku

000883101200001

EID výsledku v databázi Scopus

2-s2.0-85141226100