Spent tire rubber-derived chars and their corresponding H 3 PO 4 and CO 2 -activated chars were used as adsorbents in the recovery of Pb(II) ion and (W(VI)) oxyanion from synthetic solutions. The developed chars (both raw and activated) were thoroughly characterized to have insight about their textural and surface chemistry properties. H 3 PO 4 -activated chars presented lower surface areas than the raw chars and an acidic sur...