Method for reducing methane exhaust emissions from natural gas fueled engines

摘要

High conversion efficiencies for methane, other unburned hydrocarbons, carbon monoxide and nitrogen oxides can be obtained from a natural gas or methane fueled engine by operating the engine with an air- fuel ratio within a range that includes the stoichiometric air-fuel ratio and extends to the fuel-rich side and by employing in combination with the engine a platinum or platinum and palladium noble metal catalyst for treatment of the engine exhaust gases.