Purification of exhaust gases from motor vehicles comprises combining effects of conventional three-way catalysts with catalyst comprising powdered calcium carbonate

摘要

The presence of powered calcium carbonate supplements the action of a conventional three-way catalyst, which is ineffective until it reaches 200-300 deg C. In the purification of motor vehicle exhaust gases, the gases, directly after engine start-up, are simultaneously submitted to the three-way catalysts and to dissociated powdered calcium carbonate (CaCO3). The gases initially pass through the three-way catalyst and then through the reactor containing the CaCO3 powder. An Independent claim is also included for a reactor unit, containing CaCO3 powder, attached to the exhaust system.