The Regenerable Trap Oxidizer—An Emission Control Technique for Diesel Engines

Daimler–Benz made an early start with the development of systems for the aftertreatment of the exhaust gas emitted by diesel engines. The more important limiting conditions could best be met by the provision of a ceramic, selfcleaning trap oxidizer (TO). In such filters, self–regeneration is effected continuously while driving without any external control. Either partial or complete regeneration is effected, depending on the temperature, oxygen content and rate of flow of the exhaust gas, the amount of soot in the filter and the period for which a given operating condition is maintained. Such a trap oxidizer was developed for a 3.0 liter turbocharged diesel engine to the extent necessary for series production and has been fitted to type 300 SD and 300 D turbocharged diesel of model year 1985 in California.