TY - JOUR

T1 - On the issue of comparing the immobilization characteristics of matrix materials based on Nb–Ta–Ti-oxides of the types AB2O6 and A2B2O7

AU - Hosseinpour Khanmiri, M.

AU - Bogdanov, R.

AU - Puchkova, E.

AU - Titov, A.

AU - Yadollahi, A.

N1 - Export Date: 19 October 2024 Адрес для корреспонденции: Hosseinpour Khanmiri, M.; Nuclear Science and Technology Research Institute, Iran; эл. почта: mhosseinpourkhanmiri@aeoi.org.ir Химические вещества/CAS: oxide, 16833-27-5; uranium, 7440-61-1

PY - 2024/12/1

Y1 - 2024/12/1

N2 - In the study presented here, the initial (that is, before the start of the process of natural hydrochemical influence) mineral formula of metamict polycrase in the composition of granite pegmatites of the Baltic Shield, applying an uranium natural half-leaching period, was calculated. To investigate the characteristics of immobilization of actinides in the studied polycrase, the absolute and relative uranium contents are compared with the corresponding uranium contents in the original betafite of the same deposit and age. It has been shown that over its geological history, betafite has lost up to 80% of its original uranium content. The proportion of uranium preserved in polycrase is twice as high. It is concluded that the difference in the relative content of uranium (27.3 wt% in polycrase and 31.6 wt% in betafite) cannot be the only reason for the complete oxidation of uranium in betafite, given that in polycrase 30% of uranium is preserved in the tetravalent state. It is more likely that the oxidation of uranium in betafite was primarily a result of the low ionicity of the chemical bonds compared to that in polycrase. This allows us to consider minerals of the euxenite group to be quite promising as matrix materials for the immobilization of actinides. At the same time, an opinion was expressed on the advisability of further comparative studies of Nb–Ta–Ti-oxides of the mineral groups AB2O6 and A2B2O7 for their use at the final stage of the nuclear fuel cycle. © The Author(s) 2024.

AB - In the study presented here, the initial (that is, before the start of the process of natural hydrochemical influence) mineral formula of metamict polycrase in the composition of granite pegmatites of the Baltic Shield, applying an uranium natural half-leaching period, was calculated. To investigate the characteristics of immobilization of actinides in the studied polycrase, the absolute and relative uranium contents are compared with the corresponding uranium contents in the original betafite of the same deposit and age. It has been shown that over its geological history, betafite has lost up to 80% of its original uranium content. The proportion of uranium preserved in polycrase is twice as high. It is concluded that the difference in the relative content of uranium (27.3 wt% in polycrase and 31.6 wt% in betafite) cannot be the only reason for the complete oxidation of uranium in betafite, given that in polycrase 30% of uranium is preserved in the tetravalent state. It is more likely that the oxidation of uranium in betafite was primarily a result of the low ionicity of the chemical bonds compared to that in polycrase. This allows us to consider minerals of the euxenite group to be quite promising as matrix materials for the immobilization of actinides. At the same time, an opinion was expressed on the advisability of further comparative studies of Nb–Ta–Ti-oxides of the mineral groups AB2O6 and A2B2O7 for their use at the final stage of the nuclear fuel cycle. © The Author(s) 2024.

KW - Hydrochemical weathering processes

KW - Initial elemental composition of the mineral

KW - Isolation of actinides

KW - Mineral-like matrices

KW - Minerals of the euxenite and pyrochlore groups

KW - Uranium half-leaching period

KW - actinide

KW - mineral

KW - oxide

KW - uranium

KW - article

KW - chemical bond

KW - controlled study

KW - granite

KW - immobilization

KW - leaching

KW - nuclear fuel

KW - oxidation

KW - weathering

UR - https://www.mendeley.com/catalogue/0cb04a56-e0e3-376a-ad69-fe0c129830a5/

U2 - 10.1038/s41598-024-68984-6

DO - 10.1038/s41598-024-68984-6

M3 - статья

VL - 14

JO - Scientific Reports

JF - Scientific Reports

SN - 2045-2322

IS - 1

M1 - 17992

ER -