| 摘要 |
<p>A diolefine is obtained by the dehydrogenation of a lighter or a heavier olefine obtained from the catalytic disproportionation of an olefine feed. The preferred olefine feed is propylene; other 1- or 2-alkenes of 3-16 carbons may be used. Disproportionation is effected at 150-500 DEG F., 0-1500 p.s.i.g. with a WHSV of 0.5-20 in the presence or absence of a diluent, e.g. a paraffin or cycloparaffin of up to 12 carbons. A suitable catalyst is molybdenaalumina, optionally containing chromia, e.g. 0.5-30% molybdena, 0-20% chromia and 50-99.5% alumina. Preferably the heavier olefine product is dehydrogenated; in the case of a propylene feed this is a butene,which forms butadiene. The olefine may be separated before dehydrogenation or the whole effluent treated. Unreacted materials are recycled and heat is recovered from reaction effluents to heat reactor feeds and separating equipment.</p> |
