Abstract:
A C.sub.4 -hydrocarbon feedstream containing butenes, butadiene, and vinylacetylene is subjected to a first extractive distillation with a selective solvent to remove butenes and a first portion of vinylacetylene as the extract; by the extraction with a minor quantity of methylethyl ketone in the selective solvent in this step, it has been found that a major portion of the vinylacetylene can be rejected, together with the butenes in the rich extract and that simultaneously the quantity of butadiene extracted could be considerably reduced; in a second extractive distillation the butadiene-rich raffinate of the first extractive distillation is further purified by extractive distillation using a mixture of sulfolane and methylethyl ketone as the solvent; after solvent stripping, the butadiene stream is finally purified in a fractionation step, wherein further vinylacetylene is removed.
Abstract:
Preparation of a hydrocarbon-soluble nickel complex substantially free of moisture comprising reacting a nickel compound with an organic complexing agent in a hydrocarbon solvent to form a complex, allowing the complex to settle and separate into a water phase and a hydrocarbon solution of the complex, then drying the hydrocarbon solution of complex by azeotropic distillation. The substantially anhydrous nickel complex obtained can be mixed with an alkylaluminum halide to form a catalyst system useful for the dimerization of olefins.
Abstract:
A process and apparatus for HF alkylation wherein the vapor from the fractionation zone in which the effluent of the reaction zone is fractionated is contacted with water, the mixture formed is reacted with an olefin to form an alkyl fluoride, the alkyl fluoride is recovered and reintroduced into the alkylation reaction zone.
Abstract:
Olefins are dimerized in a loop reactor with flashing of the reactor effluent in a flashing zone within the loop. A subsequent flash in a second flashing zone can also be used for the removal of product as flash vapor. In another embodiment, separated product dimers or product heavies are used as absorbents for unreacted ethylene. The use of a vapor-liquid contacting device incorporated in the loop reactor is especially helpful in the dimerization of an olefin when the olefin is available in low-concentration gas streams. A thermosiphon loop reactor can also be used for low-concentration olefin streams to minimize the power requirements as the energy of the feed gas is used to induce the reactor circulation.
Abstract:
A gas stream containing CO.sub.2 and H.sub.2 S is contacted with an alkanolamine in a contacting zone. The rich solution is then selectively stripped in a stripping zone to produce a gas stream containing a higher CO.sub.2 :H.sub.2 S mole ratio than the initial stream. This stream can be recycled to the alkanolamine contacting zone. The partially stripped solution can be introduced into another stripping zone to provide a third gas stream which is rich in H.sub.2 S and lean in CO.sub.2 suitable as feed for a Claus Unit and a lean alkanolamine solution which can be recycled to the contacting zone.
Abstract:
A solvent system composed essentially of sulfolane and a ketone, e.g., sulfolane and methyl ethyl ketone is employed in a liquid-liquid extraction operation to separate a low boiling olefin, e.g., pentene-2, hexene-1, octene-1, etc., from a corresponding close boiling paraffin, e.g., n-pentane, n-hexane, and n-octane, respectively, and wherein solvent is recovered by employing a portion thereof in a drying or stripping column.
Abstract:
In the production of ethylfluoride by reacting ethylene with hydrofluoric acid, the addition of a very minor amount of a heavier olefin such as a C.sub.3 and/or C.sub.4 olefin greatly improves conversion and selectivity of the reaction. The product ethylfluoride can be recovered by liquid-liquid extraction.
Abstract:
A high temperature absorption process for bulk recovery of CO.sub.2 comprises contacting a gaseous mixture containing CO.sub.2, H.sub.2 S, and natural gas with C.sub.3 and heavier components and having a high and variable CO.sub.2 loading, with an amine absorbent solution at a temperature above 220.degree. F. The amine absorbent solution is continuously regenerated in a multiple section flashing so as to reduce the energy requirements for regeneration and thereby making the process more suitable for bulk recovery of CO.sub.2 from gas streams associated with enhanced oil recovery projects employing CO.sub.2 for miscible flood of oil reservoirs.
Abstract:
A gas stream containing CO.sub.2 and H.sub.2 S is contacted with an alkanolamine in a contacting zone. The rich solution is then selectively stripped in a stripping zone to produce a gas stream containing a higher CO.sub.2 :H.sub.2 S mole ratio than the initial stream. This stream can be recycled to the alkanolamine contacting zone. The partially stripped solution can be introduced into another stripping zone to provide a third gas stream which is rich in H.sub.2 S and lean in CO.sub.2 suitable as feed for a Claus Unit and a lean alkanolamine solution which can be recycled to the contacting zone.
Abstract:
The overhead stream of a deisobutanizer in an HF-alkylation plant is extracted with HF to produce a stream containing isobutane, HF and ethyl fluoride, which in turn is fractionated under a pressure of about 150 to 300 psig. The bottoms stream of this fractionation, then, is fractionated under a pressure of 50 to 145 psig to produce a relatively pure ethyl fluoride overhead stream and a relatively pure HF bottoms stream.