Olefin metathesis

摘要

The present invention is a process for the production of a mixed C4 olefinic stream comprising primarily isobutene and butene-1, and propylene, said process comprising subjecting a mixed olefin feedstock comprising C5 olefins and ethylene to metathesis in the presence of a catalyst at a temperature in the range from about -20 DEG C to 200 DEG C and subjecting the resulting metathesis product to fractionation to recover the mixed C4 stream and propylene resulting therefrom. The production of MTBE or tertiary butyl alcohol or iso-butene sulphate from this C4 stream gives rise to substantially pure butene-1 as a by-product. This method therefore obviates the need separate butene-1 from butene-2 and conventional C4 saturated hydrocarbons as would be the case if a conventional MTBE raffinate had to be processed.