Role of anions on heavy metal sorption of a cellulose modified with poly(glycidyl methacrylate) and polyethyleneimine.

The influence of anions on the equilibrium and kinetic uptake of heavy metals from an aqueous solution by a novel nitrogen-type chelating adsorbent was evaluated. Equilibrium experiments revealed that stoichiometric amounts of metals and anions are adsorbed by the resin. Kinetic studies showed that during the initial stage of adsorption, the anions are adsorbed by the adsorbent prior to the metal ions. This occurred almost simultaneously with an increase in solution pH. At equilibrium, the pH returned towards its initial value. The concentration of anion also fluctuated during the entire equilibration process. Following these observations, mechanisms governing the role of anions on enhancing capacity and rate of metal uptake of this type of chelating adsorbent type were established.