Knowhow of Fe/HBEA Catalyst for NH3-SCR of NOx in the Diesel Emissions

The iron species on fresh and aging Fe/HBEA were characterized and determined. Fe²⁺ mononitrosyls were the key intermediates in NH₃-SCR reaction. The activity of Fe-zeolites was suppressed in the presence of propene. A novel formulated Fe-BEA catalyst coating modified with MOR was designed, and the deactivation due to propene poisoning was clearly reduced.