Laponites ® for the Recovery of 133 Cs, 59 Co, and 88 Sr from Aqueous Solutions and Subsequent Storage: Impact of Grafted Silane Loads
Abstract
In this study, silylated Laponites ® (LAP) were synthetized with various loads of 3-aminopropyltriethoxysilane (APTES) to evaluate their adsorption properties of 133 Cs, 59 Co, and 88 Sr during single-solute and competitive experiments. The increase in the initial load of APTES increased the adsorbed amount of APTES in the resulted grafted clay. The characterization of LAP-APTES exhibited a covalent binding between APTES and LAP and emphasized the adsorption sites of APTES for each tested load. In comparison with raw LAP, LAP-APTES displayed significantly higher adsorption properties of Co 2+ , Cs + , and Sr 2+. The competitive adsorption of these three contaminants provides a deeper understanding of the affinity between adsorbate and adsorbent. Therefore, Co 2+ displayed a strong and specific adsorption onto LAP-APTES. Except for Cs + , the adsorption capacity was improved with increasing the load of APTES. Finally, the desorption behavior of the three contaminants was tested in saline solutions. Cs + and Sr 2+ were significantly released especially by inorganic cations displaying the same valence. Conversely, desorption of Co 2+ was very low whatever the saline solution. LAP-APTES, therefore, presented suitable adsorption properties for the removal of radionuclides especially for Co 2+ , making this material suitable to improve the decontamination of radioactive wastewaters.
Origin : Publisher files allowed on an open archive
Loading...