Fe-PILC for selective catalytic reduction of NO by propene under lean-burn conditions

Iron-pillared clays (Fe-PILC) were prepared by ion-exchange method and the iron species act as the pillaring components and active components and their performances for selective catalytic reduction of NO by propene were investigated under lean-burn conditions. XRD, N₂ adsorption/desorption, H₂-TPR, UV-vis, Py-FTIR, etc were used to characterize the catalysts. The results showed that 1.0Fe-PILC reduced more than 98% of NO at 450-600℃ and the selectivity for N₂ reached 97%. The catalytic activity of the 1.0Fe-PILC was slightly influenced by water vapor and SO₂. XRD and N₂ adsorption/desorption characterization results showed that the iron species entered the Na-Mont interlayer and formed much larger specific surface area and pore volume. H₂-TPR results indicated that Fe-PILC had a strong reduction ability at about 400 ℃, which represented the reduction of Fe³⁺→Fe²⁺. UV-vis results showed that the denitrification activity of Fe-PILC was positively correlated with the iron oxide oligomer Fe_xO_y. Py-FTIR results revealed that Lewis acid and Brønsted acid sites formed on the Fe-PILC surface. The main catalytic activity center of C₃H₆ and NO reaction was the Lewis acid site.