Research output: Contribution to journal › Article › peer-review
Structure and properties of montmorillonite containing Ca2+, Sr2+, and Ba2+ cations simultaneously. / Wang;, Cailun; Myshkin, Vyacheslav Fedorovich ; Bespala, Evgeniy Vladimirovich; Poberezhnikov, Andrey Dmitrievich; Baraban, Alexander Petrovich ; Shukshina, Daria Dmitrievna; Semenov , Dmitry Andreevich.
In: Journal of Molecular Liquids, Vol. 382, 01.07.2023, p. 121994 .Research output: Contribution to journal › Article › peer-review
}
TY - JOUR
T1 - Structure and properties of montmorillonite containing Ca2+, Sr2+, and Ba2+ cations simultaneously
AU - Wang;, Cailun
AU - Myshkin, Vyacheslav Fedorovich
AU - Bespala, Evgeniy Vladimirovich
AU - Poberezhnikov, Andrey Dmitrievich
AU - Baraban, Alexander Petrovich
AU - Shukshina, Daria Dmitrievna
AU - Semenov , Dmitry Andreevich
PY - 2023/7/1
Y1 - 2023/7/1
N2 - Most raw montmorillonites (MMT) used for radioactive waste disposal (HLW) contain Ca in the interlayer space. When HLW and MMT come into contact, various ions, such as Sr2+ and Ba2+, enter the mineral. Therefore, the article presents the results of modeling, based on molecular dynamics, for four different models for the replacement of part of Ca2+ with Sr2+ and Ba2+ ions in Ca-MMT.The general trend of MMT swelling does not change significantly after the introduction of Sr2+ and Ba2+ ions. The diffusion coefficient of water molecules increases with an increase in the number of H2O layers between mineral layers or the presence of a certain amount of large radius ions in the series Ca-MMT, Ca-Ba-MMT, Ca-Sr-MMT, Ca-Sr-Ba-MMT. It shown that in the state of single-layer clay hydration, all the studied cations form outer-sphere complexes. During two-layer clay hydration, Ca2+ tends to form outer-sphere complexes, while Sr2+ and Ba2+ ions predominantly form inner-sphere complexes. With a further increase in the number of water molecules, the interaction of Ca2+ with the basal surface of the MMT mineral layer increases.
AB - Most raw montmorillonites (MMT) used for radioactive waste disposal (HLW) contain Ca in the interlayer space. When HLW and MMT come into contact, various ions, such as Sr2+ and Ba2+, enter the mineral. Therefore, the article presents the results of modeling, based on molecular dynamics, for four different models for the replacement of part of Ca2+ with Sr2+ and Ba2+ ions in Ca-MMT.The general trend of MMT swelling does not change significantly after the introduction of Sr2+ and Ba2+ ions. The diffusion coefficient of water molecules increases with an increase in the number of H2O layers between mineral layers or the presence of a certain amount of large radius ions in the series Ca-MMT, Ca-Ba-MMT, Ca-Sr-MMT, Ca-Sr-Ba-MMT. It shown that in the state of single-layer clay hydration, all the studied cations form outer-sphere complexes. During two-layer clay hydration, Ca2+ tends to form outer-sphere complexes, while Sr2+ and Ba2+ ions predominantly form inner-sphere complexes. With a further increase in the number of water molecules, the interaction of Ca2+ with the basal surface of the MMT mineral layer increases.
KW - Cations
KW - Diffusion
KW - Hydration
KW - Inner-sphere complexes
KW - MD simulation
KW - Montmorillonite
KW - Outer-sphere complexes
KW - Swelling
UR - https://www.mendeley.com/catalogue/2c33b90f-c8df-3ff6-968e-5ac3e241d72a/
U2 - 10.1016/j.molliq.2023.121994
DO - 10.1016/j.molliq.2023.121994
M3 - Article
VL - 382
SP - 121994
JO - Journal of Molecular Liquids
JF - Journal of Molecular Liquids
SN - 0167-7322
ER -
ID: 105182085