| 摘要 |
The isomerization of olefins to transfer the double bond to a more central position is effected in two stages, the first at 140-180 DEG C. and the second at 60-100 DEG C., in each stage using a catalyst comprising supported nickel which, under the operating conditions, is present in major proportion as the element and which has been modified by treatment with sulphur, hydrogen sulphide, carbon disulphide and/or an organic sulphur compound to convert a minor proportion of the nickel to sulphide; such catalysts are described in Specification 1,002,394. The second of the two stages may be carried out by recycling over the same bed, passing over a second bed or by having a single bed with a temperature gradient. Space velocities of 0.1-20 vol./vol./hr. may be used and hydrogen may be present. 2-Methylpentene-2 is obtained from 4- and/or 2-methylpentene-1 and/or 4-methyl-pentene-2. |
