Improved stability of Co-Ferrierite catalyst by Mn in dry–wet cycles of lean CH4-SCR of NOx

Abstract

Ion-exchanged Co, Mn and Co,Mn-FER zeolite was tested as catalyst for the selective reduction of NO x with CH 4 in the presence of O 2 under dry and wet (1 vol% H 2 O) cycles. Under hydrothermal conditions Co-FER undergoes a progressive loss of activity, while Co,Mn-FER catalyst shows an increased water resistance. UV-VIS spectra of monometallic and bimetallic catalysts collected before and after dry-wet catalytic cycles show a change of Co species distribution within the zeolite upon heating and exposure to water. However, the presence of Mn prevents the decrease in the population of the most active Co 2+ site in the presence of water and stabilises the catalytic activity, as evidenced in 80 h time on stream run.

Removal of arsenic from drinking water by photo‐catalytic oxidation on MoOx/TiO2 and adsorption on γ‐Al2O3

“…Na‐K ferrierite (FER) was supplied by Engelhard. Ferrierite in ammonium form (NH 4 ‐FER) was obtained by ion exchange with a solution 1 mol L −1 of ammonium nitrate . Titanium silicate (ETS‐10) and zeolite‐L (EZ‐200) were provided by Engelhard.…”

On the enhancing effect of Ce in Pd-MOR catalysts for NOx CH4-SCR: A structure-reactivity study

“…Cobalt-containing zeolites, introduced by Li and Armor as active catalysts for CH 4 -SCR [6], have been widely studied by the scientific community [7][8][9][10][11]. This research has significantly contributed to the understanding of the nature of active species involved in this reaction, as well as the important parameters [12][13][14][15][16][17][18], Pt/Co [19,20], In/Co [21][22][23], La/Co [24], Zn/Co [25], Ag/Co [26] and Mn/Co [27]. However, the use of Co in final products such as catalytic converters may be restricted for legal reasons.…”

Combination of Nonthermal Plasma and Low Temperature-C3H8-Selective Catalytic Reduction over Co-In/H-beta Catalyst for Nitric Oxide Abatement

“…Various HCs have been tested in the SCR of NO x , including methane (Kubacka et al, 2006;She and Flytzani-Stephanopoulos, 2007), propene (Srinivasan and Rajanikanth, 2007;Park et al, 2008), and propane (Shichi et al, 2007). Recently, cobalt (Co) and indium (In)-containing catalysts were extensively studied (Ciambelli et al, 2007;Lonyi et al, 2007;Montanari et al, 2007). Zeolitesupported base-metal (Co, In) catalysts were found to have superior activity and N 2 selectivity in HC-SCR (Kubacka et al, 2006).…”