| 摘要 |
A process for the manufacture of a supported chromium oxide catalyst from a catalyst precursor, which in turn is a silica-based finely divided carrier homogeneously charged with a chromium compound-by (1) treating the catalyst precursor, with or without addition of a promoter, with an oxygen-containing gas at an elevated temperature and then (2) treating the product obtained from stage (1) with carbon monoxide, wherein, in both stages (1) and (2), the solid is in the form of a fluidized bed maintained by means of a stream of carrier gas, and wherein furthermore, in stage (1), the treatment with oxygen is carried out at from 400 DEG to 1,500 DEG C. for a period of at least 30 minutes, and in stage (2) the carbon monoxide treatment is carried out at from 250 DEG to 500 DEG C. for a period of from 0.5 to 3 hours using an anhydrous and oxygen-free gas consisting of nitrogen to which a total of from 100 to 1,000 mole %, based on the chromium trioxide content of the product obtained from stage (1), of carbon monoxide is added uniformly over the total period of the carbon monoxide treatment.
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