Monitoring synchrotron X-ray-induced radiolysis effects on metal (Fe, W) ions in high-temperature aqueous fluids
Radiolysis-induced effects on aqueous tungsten ions are observed to form a precipitate within seconds upon exposure to a synchrotron X-ray micro-beam in a WO(3) + H(2)O system at 873 K and 200 MPa. In situ Fe K-edge energy-dispersive X-ray absorption spectroscopy (ED-XAS) measurements were made on F...
Publié dans: | Journal of synchrotron radiation. - 1994. - 19(2012), Pt 5 vom: 05. Sept., Seite 797-805 |
---|---|
Auteur principal: | |
Autres auteurs: | , , , |
Format: | Article en ligne |
Langue: | English |
Publié: |
2012
|
Accès à la collection: | Journal of synchrotron radiation |
Sujets: | Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Water 059QF0KO0R Iron E1UOL152H7 Tungsten V9306CXO6G |
Résumé: | Radiolysis-induced effects on aqueous tungsten ions are observed to form a precipitate within seconds upon exposure to a synchrotron X-ray micro-beam in a WO(3) + H(2)O system at 873 K and 200 MPa. In situ Fe K-edge energy-dispersive X-ray absorption spectroscopy (ED-XAS) measurements were made on Fe(II)Cl(2) aqueous solutions to 773 K in order to study the kinetics of high-temperature reactions of Fe(2+) and Fe(3+) ions with transient radiolysis species. The radiolytic reactions in a fluid sample within a hydrothermal diamond anvil cell result in oxidation of the Fe(2+) ion at 573 K and reduction of Fe(3+) at temperatures between 673 and 773 K and of the Fe(2+) ion at 773 K. The edge-energy drift evident in the ED-XAS data directly reflects the kinetics of reactions resulting in oxidation and/or reduction of the Fe(2+) and Fe(3+) ions in the aqueous solutions at high temperatures. The oxidation and reduction trends are found to be highly consistent, making reliable determinations of reaction kinetics possible |
---|---|
Description: | Date Completed 10.01.2013 Date Revised 21.11.2013 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1600-5775 |
DOI: | 10.1107/S0909049512029093 |