| 摘要 |
1366217 Exhaust gas catalyst KNAPSACK AG 14 Nov 1972 [20 Nov 1971 29 Dec 1971] 52528/72 Heading B1E [Also in Division F1] A process for the oxidation of carbon monoxide and hydrocarbons, particularly those contained in the exhaust gas of i.c. engines, with oxygen-containing gases to carbon dioxide and water, which comprises effecting the oxidation at temperature between 100 and 700‹C in contact with a catalyst consisting of one or more oxides of copper, manganese, nickel or cobalt, the catalyst being on a support consisting of at least one alkaline earth aluminate. Preferably the oxidation is effected at temperatures between 150 and 600‹C. The support is an aluminate of barium, calcium or strontium and may additionally contain 2 to 30% by weight of one or more silicon containing compounds, e.g. silicon dioxide or magnesium silicate, preferably talc. The support may also contain between 2 and 30% by weight, preferably 5 to 20% by wt. of titanium dioxide. The support may also contain both silicon dioxide and titanium dioxide, the total amount of the two additives being 2 to 30% by weight. The carrier-supported catalyst is made by impregnating the alkaline earth metal aluminates with an aqueous solution of copper, manganese and nickel or cobalt salts of volatile acids, the quantity of solution being just sufficient to be completely absorbed by the aluminates, then heating the resulting mass to temperatures between 300 and 600‹C to decompose the salts and finally annealing the resulting catalyst at temperatures between 600 and 1200‹C. The metal salts may be nitrates of volatile acids, which are decomposed at temperatures between 350 and 450‹C and then annealed at temperatures between 600 and 1000‹C. |
