Journal Article
A New Class of Environmental Friendly Vanadate Based NH3 SCR Catalysts Exhibiting Good Low Temperature Activity and High Temperature Stability
2011-04-12
2011-01-1331
For the removal of NOx from the oxygen-rich diesel exhaust in mobile applications the selective catalytic reduction (SCR) is one of the most favored technologies. Well established NH₃-SCR technique uses either V₂O₅/WO₃-TiO₂ or Zeolite-based catalysts, NOx being continuously reduced by NH₃ resulting in the selective formation of nitrogen and water. A major drawback of V₂O₅-based formulations is their lower thermal stability and low temperature activity, in addition, V₂O₅ release poses serious environmental and toxicity problems. In active filter regeneration performed by post-injection of fuel the temperature may increase up to 800°C resulting in drastic loss of activity (due to poor stability of V₂O₅-based formulations) as well as discharge of V₂O₅.
