Sorption and diffusion behaviours of strontium in sodium-type bentonite bed

Abstract

Sorption and diffusion of Sr were examined using a typical Japanese bentonite. The experimental results showed that Sr sorption on the bentonite had linear relationship between the equilibrium Sr concentration and Sr sorption amount, i.e., Henry's type of sorption, in wide initial Sr concentration from 1.1 × 10 -9 to 1.1 × 10 -4 mol L -1 at pH 10. The Sr sorption also indicated pH dependence in pH range between 2 and 12. Sorption modelling calculation indicated that cationexchange reactions contributed to Sr sorption in the pH range studied and a surface complexation reaction was predominant above pH 8. Diffusion of Sr in loosely compacted bentonite bed was described by pore and surface diffusion and surface complexation of Sr. Chemical-transport calculations reproduce the diffusion data at pH 5 using the cation-exchange parameters obtained in the analysis of the batch sorption experiment.

Sorption and retardation of strontium in saturated Chinese loess: experimental results and model analysis

“…The extent of Sr sorption in a given environment is influenced by pH and Eh of the soil and groundwater (Khan, 2003;Kohli cková and Jedináková-K ri zová, 1998;Tsukamoto et al, 2006;Wang and An, 2004). In addition, the composition and amount of clay in soil also play a role in Sr attachment to soil particles (Bilgin et al, 2001;Murali and Mathur, 2002;Khan, 2003;Wang and An, 2004).…”

Adsorptive Removal of Strontium by Binary Mineral Mixtures of Montmorillonite and Zeolite

“…90 Sr having a longer half-life is the more frequently encountered radionuclide in soil and groundwater at nuclear weapon test sites and nuclear waste repositories . It can easily replace Ca in the bones of living organisms, being a source of long-term irradiation of bone marrow. − Adsorption of 90 Sr on surrounding minerals is one of the predominant processes controlling its mobility in an aquifer besides other interaction types including dissolution, precipitation, and redox reactions. , Natural zeolites and montmorillonite are effective clay minerals to improve the immobilizing ability of the matrix used for underground disposal of low and medium radioactive wastes. , Adsorption of Sr on montmorillonite, − clinoptilolite, − and natural clays consisting of these minerals − has been extensively studied by various researchers.…”

“…5,6 Natural zeolites and montmorillonite are effective clay minerals to improve the immobilizing ability of the matrix used for underground disposal of low and medium radioactive wastes. 7,8 Adsorption of Sr on montmorillonite, [9][10][11][12][13][14][15][16][17][18][19] clinoptilolite, [20][21][22][23][24][25][26] and natural clays consisting of these minerals [27][28][29][30][31][32] has been extensively studied by various researchers.…”