Location and migration of cations in Cu(2+)-adsorbed montmorillonite.
Environ Int
; 26(5-6): 347-52, 2001 May.
Article
en En
| MEDLINE
| ID: mdl-11392750
ABSTRACT
Locations of Cu2+ ion in Cu(2+)-adsorbed montmorillonite have been studied by electron paramagnetic resonance (EPR), supplemented by X-ray diffraction (XRD) and differential thermal analysis (DTA). In the EPR spectra of Cu(2+)-adsorbed montmorillonite, three signals, corresponding to Cu2+ ion, have been simultaneously recorded. Some Cu2+ ions seemed to replace the original interlayer metal cations and some entered into the hexagonal cavities. A small fraction of Cu2+ ions penetrated into the octahedral vacancies. There were two ways for the adsorption of Cu2+ ion by montmorillonite--exchangeable and specific. On heating, the hydrated Cu2+ ion in the interlayer loses the coordinating water and then enters into the hexagonal cavities. When the heating temperature further increased, dehydroxylation occurs, which facilitates Cu2+ ion in the hexagonal cavities to penetrate into the octahedral vacancies.
Buscar en Google
Banco de datos:
MEDLINE
Asunto principal:
Bentonita
/
Cobre
Idioma:
En
Año:
2001
Tipo del documento:
Article