Enhanced catalytic activity of Fe–Ce catalysts determined by synergistic effect of different precursors in selective catalytic reduction of NOx with NH3

Abstract

AbstractBackgroundDeveloping environmentally benign and non‐vanadium SCR catalysts remains a challenging task for NOx abatement. In this article, Fe–Ce catalysts including Fe–Ce(S) and Fe(S)–Ce catalysts with different molar ratios of Fe/Ce were synthesized by different precursors of active species expecting to gain high catalytic activity for the selective catalytic reduction (SCR) of NOx with NH3 in a wide temperature range.ResultsThe Fe–Ce(S) catalyst exhibited better catalytic activity than the Fe(S)–Ce catalyst. The characterization results indicated the Fe–Ce(S)catalyst possessed better dispersion of active species, which would favor the contact of active sites and reactant molecules and thus enhance the catalytic performance. Moreover, higher ratios of Fe3+ and Ce3+ and more surface chemisorbed oxygen were observed over the Fe–Ce(S) catalyst. In addition, the Fe–Ce(S) catalyst held better low‐temperature redox properties and more weak acid sites.ConclusionsThe precursor effect was closely related to the catalytic activity of catalysts. All of the mentioned above might be the main reasons for the superior catalytic performance of the Fe–Ce(S) catalyst, especially at low temperatures. These findings indicate that Fe–Ce(S) catalyst is a promising catalyst for the SCR reaction to replace V‐W‐Ti catalysts and can provide guidance for the development of environmentally benign and non‐vanadium SCR catalysts. © 2022 Society of Chemical Industry (SCI).