Sökning: "Bentonite"
Visar resultat 6 - 10 av 41 avhandlingar innehållade ordet Bentonite.
6. Nuclear magnetic resonance studies on bentonite in complex mixed systems
Sammanfattning : In this work 23Na MAS NMR was validated as a successful quantitative method for studies of exchanging sodium in bentonites useful, in particular, for studies of ion-exchange kinetics. Na-enriched bentonites equilibrated in a re-circulated process water at iron-oxide pelletizing plants may acquire properties of Ca-bentonites after already 20 minutes of the equilibration time, since >50 % of sodium ions will be exchanged by calcium ions during first minutes of bentonite placed in contact with the process water. LÄS MER
7. The Bentonite Barrier - Swelling Properties, Redox Chemistry and Mineral Evolution
Sammanfattning : Bentonite is planned for use as a buffer material in high-level radioactive waste repositories, where safety assessment is performed for very long periods (100-1000 ka). This thesis focuses on the swelling of smectites in liquid water, and analysis of bentonite from field experiments at Äspö Hard Rock Laboratory, Sweden. LÄS MER
8. On the sorption and diffusion of radionuclides in bentonite clay
Sammanfattning : .... LÄS MER
9. Transport of Heavy Metals in Soil Subjected to an Electric Field -A Study of the Transport of Copper in Bentonite Clay
Sammanfattning : This licentiate thesis addressesphosphorus release from sewage sludge, which is the first stepin phosphorus recovery. The concept ofphosphorus recovery maybe seen as a part of sustainable sludge handling in that it isa means of recycling resources without supplying harmfulsubstances to humans or the environment. LÄS MER
10. Interfacial properties of calcium montmorillonite in aqueous solutions : Density functional theory and classical molecular dynamics studies on the electric double layer
Sammanfattning : The swelling properties of Bentonite are highly affected by clay content and the clay-water interactions that arise from the ion distribution in the diffuse double layer formed near the charged montmorillonite (or smectite) surfaces. Existing continuum models describing the electric double layers, such as classical Poisson-Boltzmann and DLVO theory, ignore the ion-ion correlations, which are especially important for multivalent ions at high surface charge and ionic strength. LÄS MER