| 摘要 |
Unsaturated ketones are catalytically hydrogenated in a continuous process in which the ketone is evaporated, hydrogen added to the vapours by bubbling it through the liquid ketone, the mixture passed over a catalyst in a distillation column between the upper and lower fractionization elements, and the saturated ketone vapour is condensed and a portion recycled to the top of the column, whereby heat is transferred from the catalyst to the unsaturated liquid and the catalyst is cleaned by the recycled product. Suitable unsaturated ketones are mesityl oxide, isophorone and homoisophorone. The hydrogenation may be carried out at 50-250 DEG C. The hydrogen may be recycled. The catalyst may be in two separate zones and the unsaturated ketone introduced between them. The hydrogen may be mixed with an inert carrier. In the examples, isophorone is converted to trimethylcyclohexanone, and mesityl oxide to methyl isobutyl ketone. |
