Adsorption of Cs(I) and Sr(II) on Bentonites with Different Compositions at Different pH

This paper deals with adsorption regularities and mechanisms of nonradioactive Cs(I) Sr(II) analogs on bentonites different chemical mineral composition from solutions Cs Sr nitrates pH 3, 7, 10 units at constant ionic strength. The were taken the deposits Taganskoe (T), Dash-Salakhlinskoe (DS), Zyryanskoe (Z), 10th Khutor (10H). bentonite aqueous suspensions, T DS, exceeded 9 units. A less alkaline reaction was observed in suspensions Z 8.94 7.70, respectively. Bentonites DS contained significant amounts nonsilicate iron compounds, 1.0 0.5%, recovery rate studied clays ions concentrations 0.25 to 5 mmol/L varied 50% 90% decreased following order: “Ta-ganskoe” > “Dash-Salakhlinskoe” “Zyryanskoe” “10th Khutor” range. main mechanism sorption range cation fixation form outer-sphere complexes planar surfaces resulting ion exchange. Increasing (pH 6) enhanced pH-dependent positions, which allowed especially fix them more firmly as inner-sphere complexes. At 9–10, could precipitate carbonates. + accompanied by competitive interactions proton < 6 Na+, Ca2+, Mg2+, K+ cations higher values. competition apparent Cs(I)and initial 0.5 mmol/L. ability sorb large compared other determined high CEC values charge smectite T.