Patent ID: 6244044
Filing Date: 2001-06-12
Classification: B01D,F01N,Y02T

Abstract:
A method for reducing cold-start hydrocarbon emissions in a gasoline, natural gas, or propane fueled engine, comprising:providing a partial oxidation catalyst between an exhaust port of the engine and a catalytic converter;starting the engine from a cold-start;discharging an exhaust gas from the engine and introducing said exhaust gas into said partial oxidation catalyst during an initial period of engine operation, said exhaust gas introduced into said partial oxidation catalyst containing hydrocarbon and having an air/fuel ratio that has a .lambda. value of less than 1.0;passing the exhaust gas introduced into said partial oxidation catalyst during said initial period through said partial oxidation catalyst at a flow rate sufficient to provide a residence time of from about 10.sup.-2 seconds to 10.sup.-5 seconds whereby at least a portion of the hydrocarbon present in the exhaust gas discharged from the engine is partially oxidized and converted into carbon monoxide and hydrogen: and,subsequently passing the exhaust gas passed through the partial oxidation catalyst through said catalytic converter and thence into an ambient environment.