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In-Fe loaded sulfated zirconia (SZ) was firstly studied for the selective catalytic reduction (SCR) of NO with methane and exhibited higher activity than In/SZ and Fe/SZ. The addition of iron to the In/SZ increases its surface area and strong acid sites, which can be helpful for the SCR of NO. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

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 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. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In this work we studied the effect of acidity and of oxygen on the reduction of NO with CH on Pd sulphated zirconia and alumina supports under reducing and oxidizing feed conditions. The acidity of sulphated zirconia (SZ) is higher than sulphated alumina (SA). The surface acids are Lewis sites and are responsible for the NO dissociation. The introduction of Pd affects the acidity and surface area. The conversion of NO is higher on the Pd/SA than on Pd/SZ catalyst under reducing condition. The addition of O increased the oxidation of methane. The NO molecules are adsorbed dissociatively into N and O species. The higher acidity inhibits the dissociation and reaction over the metallic Pd particles. Oxygen favored the oxidation of Pd particles and influences negatively the NO conversion. Graphical Abstract: Effect of acidity and oxygen on the reduction of NO with CH on Pd sulphated zirconia and alumina supports. The introduction of Pd affects the acidity and surface area. The NO molecules are adsorbed dissociatively on the Pd/SA but not on the Pd/SZ. The higher acidity inhibits the dissociation and reaction over the metallic Pd particles. Oxygen favored the oxidation of Pd particles and influences negatively the NO conversion. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]