Distillation: processes – separatory – With disparate physical separation – Utilizing liquid-liquid extracting of distillation product
Patent
1976-09-21
1977-07-26
Bascomb, Jr., Wilbur L.
Distillation: processes, separatory
With disparate physical separation
Utilizing liquid-liquid extracting of distillation product
203 46, 203 60, 203 75, 203 77, 203 80, 203 88, 2606815R, B01D 340, C07C 708
Patent
active
040381560
ABSTRACT:
An improvement is described on a process for recovery of butadiene from a C.sub.4 hydrocarbon mixture additionally containing minor amounts of C.sub.5 saturated and unsaturated hydrocarbons, said hydrocarbon mixture being obtained as the overhead product of an initial hydrocarbon fractionation employed to separate larger quantities of C.sub.5 and heavier hydrocarbons from the hydrocarbon mixture, wherein the hydrocarbon mixture is subject to extractive distillation in the presence of a polar solvent e.g. acetonitrile, in which butadiene is separated from the fat solvent bottoms of extractive distillation by sequential low pressure flashing and stripping, followed by compression of the combined vapors of flashing and stripping with part of the compressed vapors being recycled as reboiled vapor to the extractive distillation and the remainder being again stripped at a higher pressure to recover butadiene therefrom. In this improved process, butadiene purification problems associated with carry over of C.sub.5 hydrocarbons into the fat solvent bottoms of extractive distillation are avoided by condensing a portion of the combined and compressed vapor stream from low pressure flashing and stripping to obtain a condensed liquid stream relatively rich in C.sub.5 hydrocarbons, which additionally contains butadiene and a small amount of polar solvent, followed by water washing of the condensed liquid stream to remove polar solvent therefrom and subsequent passing of the water-washed stream, substantially free of polar solvent, to the initial hydrocarbon fractionation employed to separate larger quantities of C.sub.5 and heavier hydrocarbons, whereby C.sub.5 hydrocarbons contained in the condensed liquid stream are substantially removed from the hydrocarbon mixture passed to extractive distillation.
REFERENCES:
patent: 2376425 (1945-05-01), Frey
patent: 2459410 (1949-01-01), Brandon
patent: 2920113 (1960-01-01), Pollack et al.
patent: 2993841 (1961-07-01), Sarno
patent: 3436436 (1969-04-01), Takao et al.
patent: 3436438 (1969-04-01), Takao et al.
patent: 3772158 (1973-11-01), Sarno
patent: 3798132 (1974-03-01), Sarno
patent: 3844902 (1974-10-01), Vickers et al.
Handlos Arthur E.
Knott Robert F.
Bascomb, Jr. Wilbur L.
Shell Oil Company
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