Modeling of the dynamics adsorption of some hazardous elements from aqueous solution onto bentonite-calcium-alginate beads

Abstract

Encapsulation of bentonite-Ca-alginate was employed for discharge of Cs, Sr, UO2 and Co from aquatic solution. Preferable pH for elimination of these ions was 5.5. For radiation stability, bentonite-Ca-alginate was investigated; a Co source was used to expose it to gamma radiation. Data obtained from (FT-IR) assessed radiation-induced effect on a stability of bentonite-Ca-alginate. Irradiated samples untill 100 kGy do not impair an absorption of an ions examined. In a column application, bentonite-Ca-alginate composite beads were examined for the discharge of these ions from multicomponent solution using fixed-bed column. Effect on column output of various parameters, like bed height, flow rate and initial inlet concentration were investigated. The column performance was 49, 46, 47 and 46.6% for Cs, Sr, UO2 and Co, respectively at flow rate of 0.5mL/min, 3cm bed depth and initial metal concentration, 50mg/L for each element. Thomas and Yoon-Nelson models identified a breakthrough curves, which successfully predict breakthrough adsorption curves.