Adsorption of Benzothiophene and Dibenzothiophene on Ion-Impregnated Activated Carbons and Ion-Exchanged Y Zeolites

This work mainly involved the investigation of the adsorption of benzothiophene (BT) and dibenzothiophene (DBT) on transition-metal ion-impregnated activated carbons and ion-exchanged Y zeolites. Five kinds of transition-metal ions, Ag +, Ni 2+, Zn 2+, Cu 2+, and Fe 3+, were separately loaded on activated carbons (ACs) and the Na I /Y zeolites, respectively. Adsorption isotherms were measured with the static adsorption method. Textual properties of these adsorbents were measured by using ASAP 2010. Results indicated that (1) there was no adsorption of DBT on Na I /Y because the aperture size of Na I /Y was smaller than the molecular size of BT, (2) the equilibrium amount adsorbed of BT on Ag I /Y was the highest within six ion-exchanged zeolites studied and that on Ni II /Y, Zn II /Y, Cu II /Y, and Fe III /Y became improved in comparison to Na I /Y, (3) the equilibrium amounts adsorbed of BT and DBT on the modified ACs followed the order: Ag I /AC > Ni II /AC > Cu II /AC > Zn II /AC > AC > Fe III /AC, and (4) at low BT concentrations (Cs < 3mmol/L), the ion-exchanged Y zeolites had a higher adsorption capacity of BT compared to the modified ACs because of their larger surface area of micropores, while at higher BT concentrations (7 < Cs < 10 mmol/L), the modified ACs had a higher adsorption capacity of BT because of their much larger surface area.