Selective adsorbents for germanium(IV) derived from chitosan

Branched-saccharide-chitosan resins and beads were prepared from chitosan and saccharides. Germanium(IV) was selectively adsorbed on these resins and beads from aqueous solutions containing semimetals over the range of weakly acidic to basic media. The adsorbents have large adsorption capacities of up to about 2 mmol g−1. The adsorption mechanism is ascribed to a complex formation between germanium(IV) and the hydroxy groups of the branched saccharide.