Sorption of silicates on goethite, hematite, and magnetite: Experiments and modelling

International audienceSorption of H4SiO4 (including experiments as a function of time, Kd measurement with different m/v ratios and sorption edges) onto different iron (hydro)oxides as goethite (α-FeOOH), hematite (α-Fe2O3), and magnetite (Fe3O4) has been studied with concentration of silicates under solubility limit. A surface complexation model has been used to account for sorption edge of silicates onto these iron oxide surfaces. It reveals that two types of surface complex namely FeH3SiO4 and FeH2SiO−4, are needed to describe properly the experimental observations