| 摘要 |
Catalyst system of the equilibrium type for simultaneous removal of nitrogen oxides, CO and unburnt hydrocarbons from an internal combustion engine exhaust comprises a substrate having a large specific surface area and >=0.1 wt. % of rhenium deposited upon it. The rhenium is stabilised with a refractory oxide to prevent volatilisation of its oxides. Fluctuations of the oxygen content in exhaust gases are compensated for, because in the oxygen-rich periods, rhenium is converted into its high oxidn. state and thus stores oxygen for the low-oxygen periods. In this manner uniform purificn. of exhaust gases is achieved. |
