| 摘要 |
A catalytic composition comprises a glass fabric base coated with a refractory material and having platinum, palladium or cobalt or an oxide thereof deposited thereon. The glass fabric base may be woven, knitted or crocheted and may be a quartz fabric; it may be reinforced with fine metal wires. The refractory material applied to the glass fabric may be a ceramic slip or alumina and may be applied by dipping the glass fabric in a slurry of the refractory material and drying and calcining the product. If alumina is used as the refractory material, the alumina slurry is preferably fluidized by addition of a nitrate of chromium, yttrium or samarium. In preparing the catalysts, the refractory-coated glass-fibre fabric is treated with a solution of a soluble compound of the catalytic metal, e.g. chloroplatinic acid, palladium chloride or cobalt nitrate, and the product is dried and heated to decompose the catalytic metal compound. The decomposition of a platinum or palladium compound may be facilitated by including a reducing organic compound, e.g. sugar, in the original solution. The catalysts are particularly useful for insertion in the exhaust lines of automobile engines, to decompose unsaturated hydrocarbons, nitrogen oxides and (or) carbon monoxide.
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