Reduction of nitrobenzene by steel convert slag with Fe(II) system: The role of calcium in steel slag

► Steel convert slag (SCS) adsorbed Fe(II) by ion replacement with Ca(II) in SCS. ► Adsorbed Fe(II) on SCS were able to reduce nitrobenzene to aniline. ► A three-step model was proposed for nitrobenzene reduction in SCS-Fe(II) system.