Kinetics of the Temperature-Dependent eaq - and â
OH Radical Reactions with Cr(III) Ions in Aqueous Solutions.
Chemphyschem
; 24(24): e202300465, 2023 Dec 14.
Article
em En
| MEDLINE
| ID: mdl-37877631
ABSTRACT
The reactivity of chromium(III) species with the major oxidizing and reducing radiolysis products of water was investigated in aqueous solutions at temperatures up to 150 °C. The reaction between the hydrated electron (eaq - ) and Cr(III) species showed a positive temperature dependence over this temperature range. The reaction was also studied in pHâ
2.5 and 3.5 solutions for the first time. This work also studied the reaction between acidic Cr(III) species and the hydroxyl radical (â
OH). It was found that Cr3+ did not react significantly with the â
OH radical, but the first hydrolysis species, Cr(OH)2+ , did with a rate coefficient of k= (7.2±0.3)×108 â
M-1 s-1 at 25 °C. The oxidation of Cr(OH)2+ by the â
OH radical formed an absorbing product species that ultimately oxidized to give Cr(VI). These newly measured reaction rates allow for the development of improved models of aqueous chromium speciation for the effective remediation of liquid high-level nuclear waste via vitrification processes.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Chemphyschem
Assunto da revista:
BIOFISICA
/
QUIMICA
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Estados Unidos