Exhaust Aftertreatment

Excerpt

When it comes to exhaust aftertreatment systems, there is a huge gap between public perception and actual progress. For example, approximately 140 current passenger cars with a diesel engine that complies with Euro 6 emit the same amount of NOx as one single comparable vehicle from the early 1990s. In recent decades, there has been continuous further development in the technology of exhaust aftertreatment for spark-ignition and diesel engines, which began as early as in the 1950s with the first automotive catalytic converter. The smog problem in Los Angeles motivated the French engineer Eugene Jules Houdry, who had emigrated to the United States, to found the Oxy Catalyst Company. In 1956, his company registered a patent for the first vehicle catalytic converter for spark-ignition engines. Its function was to use oxidation to split up hydrocarbons, nitrogen oxides and carbon monoxide. However, the invention was not suitable for practical application: the gasoline used at that time contained tetramethyl lead, which quickly destroyed the catalytic surfaces. …