| 摘要 |
1,255,570. Separating a mixture of C 5 hydrocarbons. METALLGESELLSCHAFT A.G. 29 July, 1970 [13 Aug., 1969], No. 36771/70. Heading C5E. A process for separating a mixture of C 5 hydrocarbons into its constituents comprising: extracting the feedstock with a selective solvent in a first countercurrent extraction step, separating an overhead fraction from the extract-laden solvent in a first extractive distillation step, paraffins and mono-olefins being obtained as refined products in the first countercurrent extraction step; supplying the bottoms from the first extractive distillation to a second extractive distillation, removing an overhead product containing all the isoprene from the second extractive distillation, separating the cyclopentadiene therefrom and recovering it as a refined product in a subsequent second countercurrent extraction using a purified solvent, the extract-loader solvent from the second extraction being supplied as an extraction solvent to the top of the second extractive distillation and cyclopentadiene being distilled from the bottoms in the second extractive distillation. The purified solvent from the second extraction should be cyclopentadiene-free and may be taken from the bottoms in the cyclopentadiene distillation. Suitable solvents are acetonitrile N-dimethylacetamide, ethanolamine, ethylene diamine DMF, butyrolactone, furfural, morpholine aniline, N-methylpyrrolidone, glycol methyl ether or a mixture thereof, optionally containing water. A paraffin countersolvent may be used in the second countercurrent extraction. |
