Efficent removal of nickel(II) salts from aqueous solution using carboxymethylchitosan-coated silica particles as adsorbent.

Three types of organo-mineral composites have been probed as adsorbents for the removal of Ni(II) ions from aqueous solution. Native Aerosil 200 silica particles have been encapsulated with carboxymethylchitosan (CM-CS) providing SiO+CM-CS, surface-silanized silica particles SiONH+CM-CS were obtained by treatment with APTES and subsequent encapsulation by CM-CS. Alternatively, surface-carboxylated Aerosil 200 was coated by CM-CS affording SiOCOH+CM-CS.