Improvements in the production of cyclohexanol

    公开(公告)号:GB888644A

    公开(公告)日:1962-01-31

    申请号:GB1568960

    申请日:1960-01-26

    Applicant: BASF AG

    Abstract: Cyclohexanol, together with mono- and dicyclohexylamine, is produced by mixing hydrogen (or a mixture of hydrogen and water-vapour) at at pressure above 60 atmospheres and preheated to 150 DEG C. to 300 DEG C., with a preheated liquid mixture of nitrobenzene and water, in such proportions that a mixing-temperature of 160 DEG C. to 250 DEG C. is established and the weight-ratio of nitrobenzene to water added in the liquidphase lies between 1 : 1 and 1 : 3, and then passing the mixture over a hydrogenationcatalyst at a hydrogen partial pressure of at least 30 atmospheres, the temperature in the catalyst-zone not being allowed to exceed 300 DEG C. In order to obtain a product which contains mainly cyclohexanol, a large amount of water (within the specified limits) and a hydrogenwater mixture preheated to 250 DEG C. to 300 DEG C. are employed. When a small amount of water is used, and the hydrogen is not preheated to such a high temperature, the product contains large proportions of mono- and dicyclohexylamine, besides cyclohexanol. Suitable catalysts are the metals or compounds of the iron or platinum group, and the oxides or sulphides of the metals of the 5th and 6th groups of the Periodic System, possibly with copper and/or manganese compounds. In an example, a 1 : 2 mixture of nitrobenzene and water, preheated to 180 DEG C. under a pressure of 200 atmospheres, and a stream of hydrogen, heated up to 250 DEG C. under pressure of 200 atmospheres, are introduced into the top of a vertical tube which contains annular filler bodies of iron in the upper section while the lower section contains granular catalyst comprising metallic nickel and metallic copper supported on silica. The mixing-temperature is 190 DEG C.; and the temperature in the reaction chamber is 275 DEG C. The gas speed is 0.35 metre per second with reference to the empty tube. The effluent vapours are condensed. The product consists of cyclohexanol (7.1%), monocyclohexylamine (19.2%) and dicyclohexylamine (9.7%).

    A process for the production of cyclohexanone

    公开(公告)号:GB874864A

    公开(公告)日:1961-08-10

    申请号:GB3247859

    申请日:1959-09-24

    Applicant: BASF AG

    Abstract: Cyclohexanone is produced from aniline or nitrobenzene by a process wherein the initial material is led with an equal or greater amount of water or steam and with an excess of hydrogen at a temperature of 150 DEG -300 DEG C. over a hydrogenation catalyst, the reaction mixture formed is cooled, freed from the gaseous constituents and reacted in a pressure vessel in the liquid state at a temperature of 250 DEG -350 DEG C. in the presence of a dehydrogenation catalyst under the vapour pressure of the water containing reaction mixture set up by the prevailing temperature, the hydrogen and ammonia formed during the reaction being removed continuously from the pressure vessel. The hydrogenation is preferably carried out at 170 DEG -225 DEG C. using metallic copper, zinc, nickel or iron or their oxides or sulphides as catalyst at normal or elevated pressure. The dehydrogenation may be carried out using metallic copper, nickel or zinc or their oxides as catalyst and at a pressure of 40-60 atmospheres. The dehydrogenation may be carried out in two or more stages using the same or increased temperatures. In an example the dehydrogenation is carried out, using finely divided copper, in three reactors connected in series where the liquid catalyst mixture is kept in motion by passing steam up through the mixture and the gases evolved are carefully decompressed so there is no appreciable vapourisation of the liquid portions.

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