Fe-Treated Artificial Zeolite as an Adsorbent for Anionic and Cationic Pollutants

Artificial zeolite (AZ) synthesized from coal fly ash was treated with iron nitrate solution of OH/Fe=2.5 and OH/Fe=0 in order to make new adsorbent for anionic and cationic pollutants. Decrease in cation exchange capacity with the iron solution treatment indicated blocking of negative charge on zeolite structure by iron species. Adsorbed iron was not released by extraction with 1 M CH3COONH4, proving that iron is strongly adsorbed on the zeolite. The AZ treated with the iron solution of OH/Fe=0 had higher capacity for phosphate adsorption. The adsorbed iron seems to become anion adsorption site newly formed on zeolite structure.