| 摘要 |
A method of decomposing nitrogen dioxide to nitrogen monoxide in an exhaust gas of a lean-burn internal combustion engine, such as a diesel engine, comprises adjusting the C1 hydrocarbon:nitrogen oxides (C1 HC:NOx) ratio of the exhaust gas to from 0.1 to 2 and contacting this exhaust gas mixture with a particulate acidic refractory oxide selected from the group consisting of zeolites, tungsten-doped titania, silica-titania, zirconia-titania, gamma-alumina, amorphous silica-alumina and mixtures of any two or more thereof and passing the effluent gas to atmosphere. |
