| 摘要 |
Phenol itself and phenols substituted by one or two alkyl radicals containing from 1 to 4 carbon atoms are produced by dehydrogenating the corresponding cyclohexanols and/or cyclohexanones at temperatures between 200 DEG and 500 DEG C. by means of a catalyst comprising as active metallic component cobalt and/or nickel in an amount of 3 to 50% by weight with reference to the whole catalyst, on a carrier which contains at least 20% of iron oxide with reference to the carrier and calculated as ferric oxide, the throughput being 0.1 to 5 Kg of the cyclohexanols and/or cyclohexanones per litre of catalyst per hour. The carrier may contain only iron oxide but preferred carriers are those containing 30 to 80% by weight of iron oxide with the remainder being made up of aluminium oxide, silicon dioxide, titanium dioxide, zinc oxide or magnesium oxide or mixtures of these oxides. The additional oxides may enter into combination with the iron oxide. Advantageously the catalyst also contain 0.2 to 10% by weight with reference to the carrier of an alkali metal oxide or an alkaline earth metal oxide and 1 to 20% by weight with reference to the active metallic components of the catalyst of a catalyst promoter, e.g. the oxides of chromium, manganese, molybdenum, tungsten and vanadium. The dehydrogenation reaction may be carried out with an addition of hydrogen and preferably in the presence of steam. For each mole of initial material it is advantateous to use 0.5 to 10 moles of water but when the initial material contains cyclohexylamines it is desirable to use in addition 12 to 100 moles of water per mole of cyclohexylamines. The process is usually carried out in the vapour phase at atmospheric pressure although increased and reduced pressures may be employed. Specification 640,363 is referred to.ALSO:A catalyst used for dehydrogenation comprises as active metallic component cobalt and/or nickel in an amount of 3 to 50% by weight with reference to the whole catalyst, on a carrier which contains at least 20% of iron oxide with reference to the carrier and calculated as ferric oxide. The iron oxide in the carrier may be present as ferrous oxide, ferric oxide or ferrosoferric oxide or mixtures thereof. The carrier may contain only iron oxide but preferred carriers are those containing 30 to 80% by weight of iron oxide with the remainder being made up of aluminium oxide, silicon dioxide, titanium dioxide, zinc oxide or magnesium oxide or mixtures of these oxides. The additional oxides may enter into combination with the iron oxide. Advantageously the catalyst also contains 0,2 to 10% by weight with reference to the carrier of an alkali metal oxide or an alkaline earth metal oxide and 1 to 20% by weight with reference to the active metallic components of the catalyst of a catalyst promoter, e.g. the oxides of chromium, manganese, molybdenum, tungsten and vanadium. Specification 640,363 is referred to. |
