Behavior of Cs in Grimsel granodiorite: sorption on main minerals and crushed rock

Abstract

<jats:title>Abstract</jats:title><jats:p>In this study the sorption of cesium was investigated on four different minerals; quartz, plagioclase, potassium feldspar and biotite as well as granodiorite obtained from the Grimsel test site in Switzerland. The experiments were conducted in the presence of the weakly saline Grimsel groundwater simulant by determining the distribution coefficients using batch sorption experiments and PHREEQC-modelling across a large concentration range. In addition, the purity of the minerals was measured byXRDand the specific surface areas by BET method using krypton. The distribution coefficients of cesiumwere largest on biotite (0.304±0.005 m</jats:p>

Characterization of spatial porosity and mineral distribution of crystalline rock using X-ray micro computed tomography, C-14-PMMA autoradiography and scanning electron microscopy

“…In previous studies, approximations have been made regarding the chemical reactions and, typically, only one reactive grain type has been used. This is not the case in real crystalline rock samples as Muuri et al (2016; have shown in their studies. In this work, we have separated the mixed mineral phases and by applying this kind of approach for sample characterization the different reactive properties of the main minerals can be taken into account in the reactive transport modeling.…”

“…Furthermore, the results of FE-SEM-EDS can be applied when adjusting parameters for mineral specific geochemical reactions and for apertures between the mineral grains. In some cases, however, further experimental studies, such as (Muuri et al 2016;Muuri et al 2017), may be needed. In previous studies, approximations have been made regarding the chemical reactions and, typically, only one reactive grain type has been used.…”

A Scaling Approach for Retention Properties of Crystalline Rock: Case Study of the In‐Situ Long‐Term Sorption and Diffusion Experiment (LTDE‐SD) at the Äspö Hard Rock Laboratory in Sweden

“…The relatively wider uncertainty ranges in the tracer depletion and penetration profile in the stub section are due to the larger uncertainties of K d values for Cs + in the fracture fillings (Figure 4a). This may be explained by the complex sorption mechanisms of Cs, such as specific sorption at frayed edge sites (FES), and the significant dependence of these mechanisms on mineralogical heterogeneities at the fracture surface and the crushing effect (e.g., Bradbury & Baeyens, 2000;Kyllönen et al, 2014;Muuri et al, 2016;Tachi et al, 2011Tachi et al, , 2020Trinchero et al, 2017;Voutilainen et al, 2017). 4).…”