Adsorption and desorption characteristics of mercury(II) ions using aminated chitosan bead.

Adsorption and desorption characteristics for mercury ions using aminated chitosan bead which showed very high affinity to mercury ions were studied. The adsorption of mercury ions using aminated chitosan bead was an exothermic process since binding strength each other increased as the temperature decreased. And the adsorption of mercury ions was almost completed in 100 min at 150 rpm. In case that adsorbent dose increased, mercury uptake capacity decreased, while, removal efficiency increased. The beads were not greatly affected by the ionic strength, organic material and alkaline-earth metal ions. Mercury ions adsorbed on aminated chitosan bead were desorbed effectively about 95% by EDTA and the adsorption capacity of the recycled beads can still be maintained at 90% level at the 5th cycle.