DIKUL - logo
E-viri
Celotno besedilo
Recenzirano
  • The use of polyacrylamide-a...
    Baybaş, Demet; Ulusoy, Ulvi

    Applied clay science, January 2011, 2011, 2011-01-00, 20110101, Letnik: 51, Številka: 1-2
    Journal Article

    The adsorption of Th4+ ions was studied on composites of polyacrylamide (PAAm) with montmorillonite (Mt), clinoptilolite (Z) and zeolite Y (ZY), and after phytic acid (Phy) modification. The monolayer adsorption capacity was 0.33 and 0.65molkg−1 for PAAm-Mt and PAAm-Mt-Phy, 0.07, 0.21 and 0.60molkg−1 for Z, PAAm-Z and PAAm-Z-Phy, and 0.74, 0.89 and 1.18molkg−1 for ZY, PAAm-ZY and PAAm-ZY-Phy. The enthalpy and entropy changes were positive for all adsorbents. The adsorption kinetics followed the pseudo-second order model indicating that the rate controlling step was chemical adsorption by ion exchange. The reusability tests for five uses proved that the PAAm-Mt and PAAm-Z were reusable and complete recovery of the adsorbed ions was possible. ZY and the composites modified with Phy were not reusable. The presence of foreign metal cations did not influence the Th4+ adsorption. The adsorbed Th4+ onto the columns was effectively recovered with diluted HNO3. ► Montmorillonite (Mt), clinoptilolite (Z) and zeolite Y were encapsulated in PAAm. ► The adsorption of Th4+ on these composites was significant. ► PAAm-Mt/Z were reusable for Th adsorption. ► The Th4+ ions were selectively adsorbed in the presence of foreign metal ions.