| 摘要 |
Hydrocarbon mixtures containing compounds having more than one olefinic bond and/or at least one acetylenic bond, but substantially free from acetylene, are selectively hydrogenated to mono-olefins in the presence of a catalyst comprising at least one metal of Group Ib, i.e. copper, silver and gold, supported on an inert carrier. The process may be applied to hydrocarbon mixtures boiling below 216 DEG C., suitably those obtained by cracking processes, and these include full boiling range gasolines, narrow fractions thereof, and substantially pure butadiene and isoprene. The Group Ib metal may constitute 1-15% by weight of the total catalyst; silver and/or copper supported on silica gel is preferred. A preferred catalyst is made by impregnating the support with copper and/or silver complexed with a water-soluble nitrogen base, particularly ammonia or ethylene diamine, and calcining. Hydrogenation may be effected at 35-345 DEG C., at 1-50 atmospheres, and in the vapour, liquid or mixed phase, liquid being preferred as the hydrogenation is exothermic, and at a L.H.S.V. of 0.5-300 kg. olefine and/or acetylene per kg. catalyst; the hydrogenating gas, which contains at least 60% H2 by volume, may be the gas obtained in the catalytic reforming of gasoline fractions. Examples describe the selective hydrogenation of isoprene (2-methylbutadiene-1,3) to isoamylene. |
