Experimental and modelling studies on diffusion of Cs, Ni and Sm in granodiorite, basalt and mudstone

Diffusion and Migration of Ions in Sedimentary Rock Matrix: Behaviour of Cesium and Iodide in Micropores of Sandstone

“…The measurements by water saturation method [1,4] were performed under about 60Torr pressure conditions for core samples with a size of φ30x50mm to accelerate the saturation and to remove air bubbles existing in the pores of the samples. In the measurements by Hg porosimetry [1,4], a sample cell with a volume of 0.5cm 3 was used, and pore sizes ≥ 3.4nm were measured. In the calculations of pore-size distribution and specific surface area of the pores, surface tension γ=0.480N/m and contact angle θ=140°were used.…”

Laboratory studies of the diffusive transport of 137Cs and 60Co through potential waste repository soils

“…Many other studies (Cho et al, 1993;Kato et al, 1995;Sato et al, 1997;Yamaguchi and Nakayama, 2001) have investigated the diffusivity of caesium, but most of these studies have only determined the apparent diffusivity, D a . This is related to the effective diffusion coefficient by:…”

“…Previous studies have concentrated on pure bentonite (eg. Muurinen, 1990;Hsu et al, 1994;Jansson and Eriksen, 2001;Molera, 2002: Garcia-Gutierrez et al, 2006Suzuki et al, 2007) because of its proposed use in manmade barriers in radioactive waste disposal, and rocks from locations of prospective waste facilities (Sato et al, 1997;Lee et al, 2009;Wersin et al, 2008). Apparent diffusivities for various radionuclides are reported in many studies (Muurinen, 1990;Hsu et al, 1994;Sato et al, 1997) but, because the apparent diffusivity is affected by porosity and sorption, and the latter is sensitive to environmental conditions, these values are not readily applicable to other sites.…”

Diffusive transport of water in porous feldspars from granitic saprolites: In situ experiments using FTIR spectroscopy

“…These predictions are in good agreement with findings for marine sediments with high porosity of 0.3-0.9 where the tortuosity factor varies between 1.2 and 4.8 (Iversen and Jørgensen, 1993). On the other hand, more consolidated media with low porosity (0.012-0.028) show much larger diffusional tortuosity factors, e.g., X values of $38, $4.5 Â 10 2 and $ 4.1 Â 10 3 were found for granodiorite, mudstone and basalt, respectively (Sato et al 1997).…”

“…In consolidated media with low porosity (0.012-0.028) the formation factors are usually very large. F values of $3.17 Â 10 3 , $2.61 Â 10 4 and $1.45 Â 10 5 are calculated for granodiorite, mudstone and basalt, respectively, using data of Sato et al (1997).…”