Novel Fe–Ce–Ti catalyst with remarkable performance for the selective catalytic reduction of NOx by NH3

Abstract

An environmentally benign Fe–Ce–Ti mixed oxide catalyst, which was prepared via the hydrothermal method, has been investigated for the selective catalytic reduction of NO_x with NH₃ (NH₃-SCR). It was found that the Fe–Ce–Ti catalyst exhibited excellent NH₃-SCR activity, high N₂ selectivity and strong resistance against H₂O and SO₂ with a wide operation temperature window. XRD and Raman spectra suggest that the Fe–Ce–Ti catalyst has an amorphous structure. The co-presence of Fe and Ce induced the formation of a redox cycle (Ce⁴⁺ + Fe²⁺ ↔ Ce³⁺ + Fe³⁺), which promotes the activation of NO and NH₃. In situ DRIFTS studies demonstrate that the synergetic effect between Fe and Ce contributes to the formation of reactive intermediate species, thus leading to the high catalytic deNO_x performance of the Fe–Ce–Ti mixed oxide catalyst.