Internal Combustion Engines, both Compression - Ignition ( CI), mainly for Diesel oil, and Spark Ignition, for Gasoline, Compressed Natural Gas (CNG) or LPG emit pollutants during operation but particularly during cold startup in addition to nitrogen, carbon dioxide and water. The POLLUTANTS are: Carbon Monoxide (CO) Unburned Hydrocarbons (HC) and Nitrogen-Oxides (NOx) All cars today must be equipped with Catalytic Converters for oxidizing the CO to C02 and the HC to C02 and water and for the reduction of the NOx to N2 and water. These catalysts are inactive at temperatures below ca. 300 deg.c and so when starting an engine from cold the emission of pollutants is high and not mitigated by the catalysts. Another problem is that a Reductant is required for the reduction of the NOx to N2 and water and the reductants in the exhaust gases namely CO and HC or Ammonia or Urea added to the flue gases are not efficient enough to fulfill the more stringent requirements for very low emission of NOx, There were many sugg
