التفاصيل البيبلوغرافية
| العنوان: |
Understanding Cd2+ Adsorption Mechanism on Montmorillonite Surfaces by Combining DFT and MD |
| المؤلفون: |
Jia Du, Qinghe Wang, Jun Chen |
| المصدر: |
Processes; Volume 10; Issue 7; Pages: 1381 |
| بيانات النشر: |
Multidisciplinary Digital Publishing Institute |
| سنة النشر: |
2022 |
| المجموعة: |
MDPI Open Access Publishing |
| مصطلحات موضوعية: |
density functional theory, molecular dynamics theory, adsorption, Cd 2+, montmorillonite |
| جغرافية الموضوع: |
agris |
| الوصف: |
The adsorption mechanism of Cd2+ on different cleavage planes of montmorillonite was investigated using density functional theory (DFT) calculations and molecular dynamics (MD) simulations. The most stable adsorption energies of Cd2+ on the (001) and (010) surfaces were −88.74 kJ/mol and −283.55 kJ/mol, respectively. On the (001) surface, Cd2+ was adsorbed on the centre of the silicon–oxygen ring by electrostatic interactions, whereas on the (010) surface, Cd2+ was adsorbed between two ≡Al–OH groups and formed two covalent bonds with O, which was mainly due to the interaction between the Cd s and O p orbitals. Upon the partial substitution of Na+ by Cd2+, Cd2+ was adsorbed on the (001) surface as inner-sphere surface complexes, with a hydration number of 5.01 and a diffusion coefficient of 0 m2/s. Whereas, when Cd2+ completely replaced Na+, part of the Cd2+ moved from the inner-sphere surface complexes to the outer-sphere surface complexes owing to its competitive adsorption. In this case, its hydration number became 6.05, and the diffusion coefficient increased to 1.83 × 10−10 m2/s. This study provides the theoretical background necessary for the development of montmorillonite-based adsorbents. |
| نوع الوثيقة: |
text |
| وصف الملف: |
application/pdf |
| اللغة: |
English |
| Relation: |
https://dx.doi.org/10.3390/pr10071381 |
| DOI: |
10.3390/pr10071381 |
| الاتاحة: |
https://doi.org/10.3390/pr10071381 |
| Rights: |
https://creativecommons.org/licenses/by/4.0/ |
| رقم الانضمام: |
edsbas.4AFC6DB2 |
| قاعدة البيانات: |
BASE |