Effect of active component addition and support modification on catalytic activity of Ag/Al 2 O 3 for the selective catalytic reduction of NOx by hydrocarbon – A review

Bimetallic AgFe Systems on Mordenite: Effect of Cation Deposition Order in the NO Reduction with C3H6/CO

“…The AgMOR monometallic catalysts at both temperatures presented low-temperature activity (~125 • C), which is attributed to the presence of Ag + ions catalyzing a mild oxidation process, since the propene is not yet activated [36]. By increasing the temperature to 350-520 • C a further increase in conversion is observed which is attributed to silver in reduced state (Ag + → Ag m n+ → Ag m → Ag 0 NPs) [65][66][67][68]. Such reduced species of silver were generated during the ionic exchange according to UV-Vis spectra (Figure 1a,b).…”

Plasma-Assisted Selective Catalytic Reduction for Low-Temperature Removal of NOx and Soot Simulant

“…This phenomenon was also observed when the CHF 3 concentration was changed to a few thousand ppm in the feed in the DBD discharge [52]. Equation (1), which is adapted from published work [53][54][55], can be used to estimate the discharge power that is suitable for the plasma-catalyst system and the sinusoidal voltage waveform in this experiment. As understood from Equation (1), the inclusion of n-heptane and naphthalene in the feed can significantly change R and C cg , due to the changes in the gas composition and the surface properties of the catalyst when adsorbing the reactants.…”

“…There is considerable attention being paid to the removal of nitrogen oxides (NO x ) and soot produced by diesel engines [1][2][3][4][5][6], because these engines using petroleum products continue to be a crucial energy source [7]. However, the emission of CO, hydrocarbons (HCs), NO x , and soot (particulate matter) from diesel engines is an environmental concern, because these gases are a major source of air pollution [8].…”

A review on pillared clay-based catalysts for low-temperature selective catalytic reduction of NO with hydrocarbons

“…In the past years, many studies have reported on the synthesis methods of different catalysts, types of carriers, catalyst stability, and NOx conversion rate under different reaction conditions (Mrad et al, 2015;Yuan et al, 2018Yuan et al, , 2019Halepoto et al, 2020;Kashif et al, 2020Kashif et al, , 2022Khan et al, 2020;Wen et al, 2020;Tang et al, 2022;Vignesh and Ashok, 2022;Xu et al, 2022;Yedala and Aghalayam, 2022). Metal oxide-supported catalysts have been found to be easy to prepare and have good hydrothermal stability at high temperatures (above 400 ºC) under high space velocity conditions (Miyahara et al, 2008;Mrad et al, 2015;More, 2017). Precious metal catalysts such as platinum, silver, rhodium, gold, and palladium supported on Al2O3, SiO2, TiO2, and ZrO2, showed good NOx reduction and better resistance to SO2 and water vapor above 400 ºC (Zhou et al, 2018;Jia et al, 2021;Yedala and Aghalayam, 2022) but they usually have a relatively low N2 selectivity and they may produce N2O as an undesired by-product.…”