Enhanced Low-Temperature Activity of Ag-Promoted Co-ZSM-5 for the CH4-SCR of NO

Abstract

Ag-promoted Co-ZSM-5 catalyst was prepared and tested for the selective catalytic reduction of NO with methane. The low-temperature activity and water-resistant ability of the promoted catalyst were markedly improved in comparison to Co-ZSM-5. The NO conversion was about 100% in the temperature range of 350-550°C at a space velocity of 6,000 h -1 and nearly 60% in the presence of 2% water steam. The results showed that with Ag presence, the redox nature of cobalt species changed. The improvement of low-temperature activity and water-resistance of catalyst is attributed to the suppression of methane combustion and the formation of surface nitrate species.

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.…”

Enhancement of the Activities of γ-Ga2O3–Al2O3 Catalysts for Methane-SCR of NO by Treatment with NH3

“…Although various zeolite catalysts have high performance for CH 4 -SCR of NO x [1][2][3][4][5][6], they are hydrothermally unstable; their frameworks are destroyed by exposure to high temperature steam [7]. Therefore, the development of active oxide-type catalysts with higher hydrothermal stability is necessary because the water content in the exhaust gases from stationary combustion plants is high.…”