| 摘要 |
1,159,053. Disproportionating olefins. BRITISH PETROLEUM CO. Ltd. 29 Jan., 1968 [13 Feb., 1967], No. 6749/67. Heading C5E. Olefins are prepared by co-disproportionating an initial mixture of an olefin R(R 1 )C = C(R 2 )R 3 , the R substituents representing hydrogen atoms or alkyl or aryl groups, with an easily polymerizable tertiary olefin containing the grouping or a secondary olefin containing the grouping wherein Ar represents an aromatic radical, in the presence of a catalyst comprising a carbonyl of Mo, W or Re supported on SiO 2 and/or Al 2 O 3 the support having been modified by addition of a minor proportion of alkali or alkaline earth metal ions prior to combining the support with the carbonyl. The catalyst may comprise 0.1-20% by wt. of carbonyl and 0.02-5% by wt. of added metal ion. The support may be subjected to thermal activation, after adding the metal ions, either in a stream of an inert gas (e.g. N 2 , CO 2 or He) or in a stream of air or O 2 followed by final treatment in an inert gas. In an example a feed containing butene-2 and isobutene was co-disproportionated over a catalyst comprising Al 2 O 3 , molybdenum carbonyl and sodium to give a product containing propylene and 2-methylbutene-2. An inert diluent such as a paraffin or cycloparaffin may be present. |
