Gamma radiolysis of hydrophilic diglycolamide ligands in concentrated aqueous nitrate solution
The radiation chemistry of a series of hydrophilic diglycolamides (DGAs: TEDGA, Me-TEDGA, Me 2 -TEDGA, and TPDGA) has been investigated under neutral pH, concentrated aqueous nitrate solution conditions. A combination of steady-state gamma and time-resolved pulsed electron irradiation experiments, s...
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Published in | Dalton transactions : an international journal of inorganic chemistry Vol. 48; no. 45; pp. 175 - 1713 |
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Main Authors | , , , , , , , , |
Format | Journal Article |
Language | English |
Published |
Cambridge
Royal Society of Chemistry
19.11.2019
Royal Society of Chemistry (RSC) |
Subjects | |
Online Access | Get full text |
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Summary: | The radiation chemistry of a series of hydrophilic diglycolamides (DGAs: TEDGA, Me-TEDGA, Me
2
-TEDGA, and TPDGA) has been investigated under neutral pH, concentrated aqueous nitrate solution conditions. A combination of steady-state gamma and time-resolved pulsed electron irradiation experiments, supported by advanced analytical techniques and multi-scale modeling calculations, have demonstrated that: (i) the investigated hydrophilic DGAs undergo first-order decay with an average dose constant of (−3.18 ± 0.23) × 10
−6
Gy
−1
; (ii) their degradation product distributions are similar to those under pure water conditions, except for the appearance of NO
x
adducts; and (iii) radiolysis is driven by hydroxyl and nitrate radical oxidation chemistry moderated by secondary degradation product scavenging reactions. Overall, the radiolysis of hydrophilic DGAs in concentrated, aqueous nitrate solutions is significantly slower and less structurally sensitive than under pure water conditions, similar to their lipophilic analogs. Acid hydrolysis, not radiolysis, is expected to limit their useful lifetime. These findings are promising for the deployment of hydrophilic DGAs as actinide aqueous phase stripping and hold-back agents, due to the presence of high concentrations of nitrate in envisioned large-scale process conditions.
Advanced analytical techniques and predictive multi-scale modeling calculations show that gamma radiolysis of hydrophilic diglycolamides in concentrated, aqueous nitrate solutions is significantly slower and less structurally sensitive than under pure water conditions. |
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Bibliography: | Electronic supplementary information (ESI) available: HPLC-ESI-MS/MS solvent gradients, reaction kinetics figures, and degradation product tables. See DOI 10.1039/c9dt03918j ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22) USDOE Office of Nuclear Energy (NE) AC07-05ID14517; FC02-04ER15533; SC0012704; NE0008406 |
ISSN: | 1477-9226 1477-9234 |
DOI: | 10.1039/c9dt03918j |