The open literature concerning chemical and mechanistic aspects of the selective catalytic reduction of NO by ammonia (SCR process) on metal oxide catalysts is reviewed. Catalytic systems based on supported V2O5 (including the industrial TiO2-supported V2O5–WO3 and/or V2O5–MoO3 catalysts) and catalysts containing Fe2O3, CuO, MnOx and CrOx are considered. The results of spectroscopic studies of the adsorbed surface species, adsorption–desorption measurements, flow reactor and kinetic experiments are analyzed. The proposed reaction mechanisms are described and critically discussed. Points of convergence and of disagreement are underlined.

Chemical and mechanistic aspects of the selective catalytic reduction of NOx by ammonia over oxide catalysts: A review

Hydrogen production reactions from carbon feedstocks: fossil fuels and biomass.

Selective catalytic reduction with NH3 (NH3-SCR) is the most efficient technology to reduce the emission of nitrogen oxides (NOx) from coal-fired industries, diesel engines, etc. Although V2O5-WO3(MoO3)/TiO2 and CHA structured zeolite catalysts have been utilized in commercial applications, the increasing requirements for broad working temperature window, strong SO2/alkali/heavy metal-resistance, and high hydrothermal stability have stimulated the development of new-type NH3-SCR catalysts. This review summarizes the latest SCR reaction mechanisms and emerging poison-resistant mechanisms in the beginning and subsequently gives a comprehensive overview of newly developed SCR catalysts, including metal oxide catalysts ranging from VOx, MnOx, CeO2, and Fe2O3 to CuO based catalysts; acidic compound catalysts containing vanadate, phosphate and sulfate catalysts; ion exchanged zeolite catalysts such as Fe, Cu, Mn, etc. exchanged zeolite catalysts; monolith catalysts including extruded, washcoated, and metal-mesh/foam-based monolith catalysts. The challenges and opportunities for each type of catalysts are proposed while the effective strategies are summarized for enhancing the acidity/redox circle and poison-resistance through modification, creating novel nanostructures, exposing specific crystalline planes, constructing protective/sacrificial sites, etc. Some suggestions are given about future research directions that efforts should be made in. Hopefully, this review can bridge the gap between newly developed catalysts and practical requirements to realize their commercial applications in the near future.

Selective Catalytic Reduction of NOx with NH3 by Using Novel Catalysts: State of the Art and Future Prospects.

Raman and IR studies of surface metal oxide species on oxide supports: Supported metal oxide catalysts

This paper surveys the present status and the perspective of de-NO x SCR catalysis for stationary sources, that is based on the reduction of NO x by NH 3 to form water and nitrogen. After a brief description of the SCR chemistry the characteristics of commercial SCR catalysts, their physico-chemical properties and reactivity, and their performances in both NO x reduction and SO 2 oxidation are presented. The mechanism of the SCR reactions, the mathematical modeling of the reactor and the arrangements of the reactor and process are then described. Finally the emerging technologies for NO x removal and the future perspectives of the SCR catalysis are outlined.

Present status and perspectives in de-NOx SCR catalysis

Reactivity of V2O5-WO3/TiO2 catalysts in the selective catalytic reduction of nitric oxide by ammonia

Production of hydrogen from oxidative steam reforming of methanol: II. Catalytic activity and reaction mechanism on Cu/ZnO/Al2O3 hydrotalcite-derived catalysts

Characterization and reactivity of MoO3/SiO2 catalysts in the selective catalytic oxidation of ammonia to N2

On the consistency of data obtained from different techniques concerning the surface structure of vanadia-titania catalysts: Reply to the comment of Israel E. Wachs

G. Ramis

Papers

Reactivity of V2O5-WO3/TiO2 catalysts in the selective catalytic reduction of nitric oxide by ammonia

Production of hydrogen from oxidative steam reforming of methanol: II. Catalytic activity and reaction mechanism on Cu/ZnO/Al2O3 hydrotalcite-derived catalysts

Characterization and reactivity of MoO3/SiO2 catalysts in the selective catalytic oxidation of ammonia to N2

On the consistency of data obtained from different techniques concerning the surface structure of vanadia-titania catalysts: Reply to the comment of Israel E. Wachs

Cu–Zn–Al hydrotalcites as precursors of catalysts for the production of hydrogen from methanol