To Recover Unsaturate Patents (Class 585/809)
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Patent number: 6015933Abstract: A process to remove polymeric by-products from the product of an acetylene selective hydrogenation reactor has been developed. The product is generated by introducing hydrogen and a liquid hydrocarbon stream containing largely butadiene and some acetylenes to a reactor containing a catalyst effective for the selective hydrogenation of acetylenes. The product contains at least hydrogen, butadiene, and polymeric by-products. The pressure of the product is reduced and the product cooled. The cooled product is conducted to a low pressure flash drum to produce a hydrogen enriched stream and a butadiene and polymeric by-product-enriched stream. The hydrogen-enriched stream is removed. The butadiene and polymeric by-product is passed to a knockout drum to produce a stream enriched in butadiene and polymeric by-products having less than about 12 carbon atoms and a stream enriched in polymeric by-products having about 12 or more carbon atoms.Type: GrantFiled: July 15, 1998Date of Patent: January 18, 2000Assignee: UOP LLCInventors: Hayim Abrevaya, Bipin V. Vora
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Patent number: 5986157Abstract: Carbonyl compound contaminants are removed from hydrocarbon streams containing olefins for use, for example, in the process for the skeletal isomerization of olefins by pretreating the hydrocarbon stream by passing it over an acidic catalyst at elevated temperatures in the range of 100-400.degree. C. under conditions to react the carbonyls to form reaction products which are deposited onto the catalyst.Type: GrantFiled: February 3, 1998Date of Patent: November 16, 1999Assignee: Catalytic Distillation TechnologiesInventor: J. Yong Ryu
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Patent number: 5955640Abstract: Integrated process for the production of butene-1 which comprises feeding a C.sub.4 hydrocarbon stream to a separation unit of butene-1 and recycling the remaining stream to the same unit after treatment in a bond isomerization section to convert the remaining butenes-2 into butene-1, a molecular sieve separation unit is inserted in the cycle operating with the hydrocarbons in a vapour phase, for the purge of the paraffins.Type: GrantFiled: May 24, 1996Date of Patent: September 21, 1999Assignees: Enichem S.p.A., Snamprogetti S.p.A.Inventors: Renato Paludetto, Alfredo Orsi, Roberto Trotta, Gianni Donati
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Patent number: 5942656Abstract: A process for separating linear alpha olefins from branched alpha olefins in a feed stream by:a) contacting the feed stream with a linear polyaromatic compound having at least four fused aromatic rings, such as 2,3-benzanthracene, under conditions effective to form a reaction mixture comprising a linear polyaromatic compound-linear alpha olefin adduct;b) separating the linear polyaromatic compound-linear alpha olefin adduct from the reaction mixture;c) dissociating the linear polyaromatic compound-linear alpha olefin adduct to form the linear polyaromatic compound and a linear alpha olefin composition, and optionallyd) separating the linear polyaromatic compound formed in step c) from the linear alpha olefin composition.Type: GrantFiled: December 9, 1997Date of Patent: August 24, 1999Assignee: Shell Oil CompanyInventors: Lynn Henry Slaugh, Laurent Alain Fenouil, Howard Lam-Ho Fong
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Patent number: 5942655Abstract: A process for the removal of trace quantities of polynuclear aromatic compounds from the vapor effluent of a hydrocarbon dehydrogenation zone containing normally gaseous olefinic hydrocarbons, trace mononuclear aromatic compounds and trace polynuclear aromatic compounds by contacting the vapor effluent of a hydrocarbon dehydrogenation zone with a lean liquid absorption stream comprising at least one alkylated mononuclear aromatic compound to absorb at least a portion of the trace mononuclear aromatic compounds and the trace polynuclear aromatic compounds to produce a rich liquid absorption stream and a gaseous olefin-containing hydrocarbon stream having a reduced concentration of mononuclear aromatic compounds and polynuclear aromatic compounds. The rich liquid absorption stream is separated to produce a stream rich in mononuclear aromatic compounds, a stream rich in alkylated mononuclear aromatic compounds and a stream comprising polynuclear aromatic compounds.Type: GrantFiled: September 9, 1997Date of Patent: August 24, 1999Assignee: UOP LLCInventor: Bryan K. Glover
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Patent number: 5939596Abstract: The present invention provides a process and system for the removal of butadiene from a cracked gas stream prior to entering a front end hydrogenation reactor in an olefin production facility.Type: GrantFiled: January 12, 1998Date of Patent: August 17, 1999Assignee: Stone & Webster Engineering Corp.Inventor: Mark Whitney
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Patent number: 5936136Abstract: Linear alpha olefins are separated from 2-branched alpha olefins and/or 3-branched alpha olefins. A feedstock of linear alpha olefins, branched alpha olefins, and internal olefins is converted to a linear alpha olefin composition having a lower concentration of branched alpha olefins than present in the feedstock bya) contacting the feedstock with anthracene under conditions effective to form a reaction mixture comprising an anthracene-linear alpha olefin adduct;b) separating the anthracene-linear alpha olefin adduct from the reaction mixture;c) disassociating the anthracene-linear alpha olefin adduct to form anthracene and a linear alpha olefin composition, andd) separating the anthracene formed in step c) from a linear alpha olefin composition.Type: GrantFiled: June 16, 1997Date of Patent: August 10, 1999Assignee: Shell Oil CompanyInventors: Lynn Henry Slaugh, Howard Lam-Ho Fong, Laurent Alain Fenouil
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Patent number: 5925799Abstract: In an olefins plant for the production and recovery of ethylene and propylene, the hydrogenation of the C.sub.2 acetylenes, the C.sub.3 acetylenes and dienes and the C.sub.4 and heavier acetylenes, dienes and olefins and the selective separation of the resulting products is carried out by the use of various arrangements of one or more reaction distillation columns. These columns contain a hydrogenation catalyst in enriching and stripping sections and concurrently perform a catalytic hydrogenation reaction and a distillation function.Type: GrantFiled: August 19, 1997Date of Patent: July 20, 1999Assignee: ABB Lummus Global Inc.Inventors: Stephen J. Stanley, Charles Sumner
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Patent number: 5907076Abstract: A process is disclosed for the separation and removal of hydrogen, alone or together with carbon monoxide, from a mixture of these gases with olefinic hydrocarbons by contacting the mixture with oxygen over a catalyst at conditions sufficient to oxidize the hydrogen to form water while suppressing reaction of the reactive, unsaturated hydrocarbons. The catalyst contains at least one metal or metal oxide from Groups Ib, IIb, IIIa, IVa and Va of the Periodic Table, and the temperature of the reaction may range from about 40.degree. C. to 300.degree. C. and a pressure of about 14.7 psig to 1,000 psig, and the flow rate of the entering feed ranges from about 1 GHSV to about 50,000 GHSV. The process can be conducted using one, two or three reaction zones.Type: GrantFiled: June 23, 1997Date of Patent: May 25, 1999Assignee: Exxon Chemical Patents Inc.Inventors: Di-Yi Ou, Stephen Neil Vaughn, Lawrence Gilbert Daniel
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Patent number: 5880320Abstract: Gases and liquid products of the cracking zone of a ethylene production plant fractionated in a demethanizer to from a dilute ethylene stream containing about 5 to about 40 percent of the ethylene contained in the feed. The dilute ethylene is feed to an ethylbenzene plant and reacts with impure benzene. The product ethylbenzene is normally converted to styrene.Type: GrantFiled: October 24, 1997Date of Patent: March 9, 1999Inventor: David Netzer
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Patent number: 5877378Abstract: The alpha-olefin content of mixed hydrocarbon streams is selectively utilized to produce trialkylaluminum compounds in which the alkyl groups are linear primary alkyl groups. This selective utilization is accomplished by use of a specific, highly selective low residence-time, low isomerization catalytic displacement reaction. In addition, when alpha-olefins are the desired end product, a second low residence-time catalytic displacement reaction is utilized whereby high purity alpha olefins are produced.Type: GrantFiled: September 15, 1997Date of Patent: March 2, 1999Assignee: Amoco CorporationInventors: Andrew D. Overstreet, Robert H. Allen, Larry H. Nemec, Ronny W. Lin
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Patent number: 5877380Abstract: The viscosity of quench oil circulated in a pyrolysis fractionation unit is controlled by contacting pyrolysis furnace effluent with a slip stream of 0.1-0.5 kg/kg of the quench oil, separating the resulting vapor-liquid mixture to remove tarry liquid, and feeding the remaining vapor to the fractionator. Removing the tarry liquid from the fractionator feed in this manner allows operation of the fractionator with less reflux, a higher bottoms temperature, and more heat recovery at a higher temperature.Type: GrantFiled: October 27, 1997Date of Patent: March 2, 1999Assignee: The M. W. Kellogg CompanyInventors: Brendan Patrick Conroy, Vijender Kumar Verma
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Patent number: 5864052Abstract: The invention relates to a process for preparing di-n-butene and alkyl tertbutyl ethers in a coupled production from field butanes, which indicates (a) separating the field butanes 1 into n-butane and isobutane in the separation stage 4, (b) dehydrogenating the n-butane 5 in a dehydrogenation stage 6 to give an n-butene-containing dehydrogenation mixture 7, oligomerizing the n-butene in the oligomerization stage 10 to give an oligomer mixture 11 and separating di-n-butene 12 off from this, and (c) de-hydrogenating the isobutane 15 in the dehydrogenation stage 16 to give an isobutene-containing dehydrogenation mixture 17 and reacting the isobutene with an alkanol 20 in the etherification stage 19 to give an alkyl tert-butyl ether 21.Type: GrantFiled: July 24, 1997Date of Patent: January 26, 1999Assignee: Huels AktiengesellschaftInventors: Franz Nierlich, Paul Olbrich, Wilhelm Droste, Richard Mueller, Walter Toetsch
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Patent number: 5859304Abstract: The present invention provides an improved method for recovering high purity olefins from cracked gas effluents or other parafin/olefin gaseous mixtures by use of a chemical absorption process.Type: GrantFiled: December 13, 1996Date of Patent: January 12, 1999Assignee: Stone & Webster Engineering Corp.Inventors: Richard Barchas, Richard McCue, Jr., Christopher Wallsgrove, Mark Whitney
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Patent number: 5849979Abstract: A process for the removal of trace quantities of polynuclear aromatic compounds from the vapor effluent of a hydrocarbon dehydrogenation zone containing normally gaseous olefinic hydrocarbons, trace mononuclear aromatic compounds and trace polynuclear aromatic compounds by contacting the hot vapor effluent of a hydrocarbon dehydrogenation zone with a cold lean liquid absorption stream to absorb at least a portion of the trace polynuclear aromatic compounds to produce a rich liquid absorption stream and a gaseous olefin-containing hydrocarbon stream having a reduced concentration of polynuclear aromatic compounds.Type: GrantFiled: March 6, 1997Date of Patent: December 15, 1998Assignee: UOP LLCInventors: Tom N. Kalnes, Bryan K. Glover, Lester F. Smith, Norman H. Scott
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Patent number: 5811621Abstract: A polymerizable grade of ethylene is recovered from an olefin-containing composition, prepared by the conversion of a methoxy compound to olefins, by a process which significantly reduces the requirements of the demethanizer distillation column through which hydrogen and methane are eliminated as impurities from the ethylene product without suffering economically unacceptable losses of ethylene to the hydrogen-methane fraction that is separated. The invention also provides for a C-2 splitter column of simplified requirements.Type: GrantFiled: August 9, 1996Date of Patent: September 22, 1998Inventor: Christiaan P. van Dijk
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Patent number: 5792899Abstract: A process for the management of polynuclear aromatic compounds produced in a hydrocarbon dehydrogenation zone wherein the effluent from the hydrocarbon dehydrogenation zone is contacted with an adsorbent to reduce the concentration of polynuclear aromatic compounds. The resulting dehydrogenated hydrocarbon having a reduced concentration of polynuclear aromatic compounds is reacted with methanol to produce an ether. A portion of the ether is contacted with a spent bed of adsorbent to recover at least a portion of the polynuclear aromatic compounds adsorbed thereon to thereby regenerate the adsorbent.Type: GrantFiled: September 27, 1996Date of Patent: August 11, 1998Assignee: UOP LLCInventor: Paul R. Cottrell
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Patent number: 5792898Abstract: A process for the management of polynuclear aromatic compounds produced in a hydrocarbon dehydrogenation zone wherein the effluent from the hydrocarbon dehydrogenation zone containing dehydrogenated hydrocarbons, dehydrogenatable hydrocarbons and trace quantities of mononuclear and polynuclear aromatic hydrocarbons is admixed with a recycle stream containing mononuclear aromatic compounds and the resulting admixture is contacted with an adsorbent to reduce the concentration of mononuclear and polynuclear aromatic compounds and to produce a stream comprising dehydrogenated hydrocarbons and dehydrogenatable hydrocarbons. An off-line spent adsorbent containing mononuclear and polynuclear aromatic compounds is contacted with a hot hydrogen-rich gas to recover at least a portion of said mononuclear and polynuclear aromatic compounds to thereby regenerate the spent adsorbent.Type: GrantFiled: September 27, 1996Date of Patent: August 11, 1998Assignee: UOP LLCInventor: Bryan K. Glover
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Patent number: 5763715Abstract: The present invention provides a process and system for the removal of butadiene from a cracked gas stream prior to entering a front end hydrogenation reactor in an olefin production facility.Type: GrantFiled: October 8, 1996Date of Patent: June 9, 1998Assignee: Stone & Webster Engineering Corp.Inventor: Mark Whitney
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Patent number: 5756872Abstract: A process wherein an FCCU off gas is treated by first subjecting the off gas to an alkylation with a heavy reformat to remove the propylene and contaminants after which the gas is separated from the reformat and alkylated products by distillation to produce an ethylene feed suitable for the reaction with benzene to produce ethyl benzene.Type: GrantFiled: January 27, 1997Date of Patent: May 26, 1998Assignee: Catalytic Distillation TechnologiesInventors: Lawrence A. Smith, Jr., John R. Adams
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Patent number: 5744685Abstract: A process is disclosed for the separation and recovery of an unsaturated hydrocarbon from its mixture with at least one other material by the selective and reversible complexation of the unsaturated hydrocarbon using a single cubane-type cluster of palladium, molybdenum and sulfur as a complexation agent.Type: GrantFiled: October 15, 1996Date of Patent: April 28, 1998Assignee: Amoco CorporationInventors: Robert B. Wilson, Jr., Karen Meyer, Marianna F. Asaro
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Patent number: 5710357Abstract: A safe, effective, and economical method is provided for recovering olefins from cat-cracked gases without accumulating dangerous amounts of nitrogen oxides. A stream of cat-cracked gas first is scrubbed to remove acid gases, including nitrogen dioxide (NO.sub.2), and then is passed through a depropanizer fractionation tower. Hydrocarbons having four or more carbon atoms are recovered in the bottoms of the depropanizer, and the overhead from the depropanizer--which is composed of hydrocarbons having three or fewer carbon atoms--is sent to an absorber demethanizer tower. Hydrocarbons having two or more carbon atoms are recovered in the bottoms from the absorber demethanizer tower, where temperatures are no lower than about -45.56.degree. C. (-50.degree. F.) The overhead from the absorber demethanizer tower--which is composed of methane, hydrogen, and trace amounts of nitrogen oxide, C.sub.2, and absorbent (C.sub.3)--then is chilled to condense and recover trace amounts of C.sub.Type: GrantFiled: June 5, 1995Date of Patent: January 20, 1998Assignee: Exxon Chemical Patents Inc.Inventors: Dane Clark Grenoble, Roy Thomas Halle, William Douglas Thomson
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Patent number: 5675054Abstract: The invention is a process for reducing capital and energy costs in ethylene recovery. Moderate pressure processing and thermally coupled fractionation steps are achieved through the use of integrator columns. Ethylene separation from cracked gas originating from ethane through gas oil feeds can now be done with thermodynamically efficient fractionation at capital cost competitive with low efficiency designs. Acetylene hydrogenation may be done before demethanization where desired, and dephlegmation is preferred to accomplish high-efficiency rectification of hydrogen and methane from ethylene. Open loop heat pumps can optionally be incorporated into the ethane/ethylene splitter fractionation step, whose desirability is controlled by optimization of capital and energy costs.Type: GrantFiled: July 17, 1995Date of Patent: October 7, 1997Inventors: David Manley, Hazem Haddad
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Patent number: 5602290Abstract: A process is disclosed for pretreating a dilute ethylene feedstock with benzene, ethylbenzene, or mixtures thereof to reduce the higher olefin content of the ethylene feedstock and to render it suitable as the feed to an alkylation reactor for producing ethylbenzene. Benzene and ethylbenzene recovery are integrated with other downstream operations in the ethylbenzene production.Type: GrantFiled: May 30, 1995Date of Patent: February 11, 1997Assignee: Raytheon Engineers & Constructors, Inc.Inventor: Kevin J. Fallon
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Patent number: 5595634Abstract: A process for treating C.sub.3 to C.sub.12 petroleum fractions, such as a light cracked naphtha to be used as an etherification feed stock in which H.sub.2 S is removed by distillation of at least the C.sub.3 fraction and mercaptans and diolefins are removed simultaneously in a distillation column reactor using a dual catalyst bed. The mercaptans and H.sub.2 S are reacted with the diolefins in the presence of a reduced nickel catalyst to form sulfides which are higher boiling than the portion of the feed which is fractionated to an upper hydrogenation catalyst bed of palladium for hydrogenating diolefins and acetylenes. The higher boiling sulfides are removed as bottoms along with heavier materials. Any diolefins not converted to sulfides and acetylenes are selectively hydrogenated to mono-olefins in the presence of a palladium oxide catalyst in an upper bed, producing overheads, substantially free of sulfur compounds, diolefins and acetylenes.Type: GrantFiled: July 10, 1995Date of Patent: January 21, 1997Assignee: Chemical Research & Licensing CompanyInventors: Dennis Hearn, Gary R. Gildert, Hugh M. Putman
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Patent number: 5569788Abstract: A process is directed to the removal of impurities such as sulfur compounds, oxygenates, and/or olefins from a light paraffin hydrocarbon feedstock such as a C.sub.4 -C.sub.6 fraction, which may be used subsequently in an isomerization process in an integrated complex for the production of ethers such as MTBE and TAME. The hydrocarbon feedstream is passed to a removal zone wherein the hydrocarbon feedstream is contacted with a selective solvent for the removal of the impurities comprising at least one of sulfur compounds, oxygenates and olefins to provide a rich solvent stream and a treated hydrocarbon stream. The rich solvent comprising the trace impurities is contacted with a stripping medium stream to regenerate the selective solvent in a stripping zone. The removal zone may be a liquid-liquid extraction zone or a gas absorption zone.Type: GrantFiled: March 20, 1995Date of Patent: October 29, 1996Assignee: UOPInventors: Paulino Forte, Stanley J. Frey
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Patent number: 5551972Abstract: An absorption process for separating a feed gas stream having components with a spectrum of volatilities including volatile (light) components, intermediate volatility components, and least volatile (heavy) components. The disclosed process includes the steps of: (1) contacting the feed gas stream with an internally generated liquid lean solvent stream in an absorber to produce a light product gas stream that is composed of predominantly light components and a rich solvent stream containing most of the intermediate and heavy components; (2) flashing the rich solvent stream at reduced pressure in a flash zone to produce an intermediate product gas stream composed predominantly of intermediate components and a lean solvent stream; (3) conveying the lean solvent stream from the flashing zone to the absorber, wherein the lean solvent is composed predominantly of heavy components supplied from the feed; the process does not use an external lean solvent.Type: GrantFiled: August 23, 1995Date of Patent: September 3, 1996Assignee: Advanced Extraction Technologies, Inc.Inventors: Glenn C. Wood, Yuv R. Mehra
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Patent number: 5516965Abstract: The invention relates to a process for recovering unreacted unsaturated hydrocarbons from an effluent stream of a process for synthesizing oxygenated hydrocarbons from unsaturated hydrocarbons, said stream containing unreacted unsaturated hydrocarbons, oxygenated reaction products, and low-boiling gaseous components selected from the group including CO, H.sub.2, CO.sub.2, H.sub.2 O, C.sub.1 -C.sub.5 alkanes, nitrogen, helium, and argon by absorbing the unreacted unsaturated hydrocarbons and the oxygenated hydrocarbons of the synthesis process effluent stream in a solvent wherein said solvent is an unsaturates-depleted stream of the oxygenated product of said synthesis process, and stripping the unsaturated hydrocarbons from the solvent to produce a first stream concentrated in unsaturates and a second stream of oxygenated product depleted in unsaturates, wherein said unsaturates-depleted stream is the absorption solvent and the synthesis process product.Type: GrantFiled: January 18, 1995Date of Patent: May 14, 1996Assignee: Exxon Research and Engineering CompanyInventors: Frank Hershkowitz, Gabor Kiss
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Patent number: 5462583Abstract: An absorption process for separating a feed gas stream having components with a spectrum of volatilities including volatile (light) components, intermediate volatility components, and least volatile (heavy) components. The disclosed process includes the steps of: (1) contacting the feed gas stream with a liquid lean solvent stream in an absorber to produce a light product gas stream that is composed of predominantly light components and a rich solvent stream containing most of the intermediate and heavy components; (2) flashing the rich solvent stream at reduced pressure in a flash zone to produce an intermediate product gas stream composed predominantly of intermediate components and a lean solvent stream; (3) conveying the lean solvent stream from the flashing zone to the absorber, wherein the lean solvent is composed predominantly of heavy components taken from the feed; the process does not use an external lean solvent.Type: GrantFiled: March 4, 1994Date of Patent: October 31, 1995Assignee: Advanced Extraction Technologies, Inc.Inventors: Glenn C. Wood, Yuv R. Mehra
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Patent number: 5463137Abstract: A propylene stream which contains propane as an impurity is contacted with carbon monoxide and hydrogen in the presence of a hydroformylation catalyst thereby producing a product stream containing butyraldehyde and/or n-butyl alcohol, unreacted propylene and propane. A gas mixture containing propylene and propane is separated from the product stream and subjected to adsorption at a temperature of 0.degree. to 250.degree. C. in a bed of adsorbent which selectively adsorbs propylene, thereby adsorbing substantially all of the propylene from the gas mixture. The propylene is desorbed from the adsorbent and recycled to the reaction zone. The process is operated on a low per pass conversion with recycle of unreacted propylene. In the system of the invention the propylene adsorption unit may be upstream or downstream of the hydroformylation reactor.Type: GrantFiled: April 22, 1994Date of Patent: October 31, 1995Assignee: The BOC Group, Inc.Inventors: Ramakrishnan Ramachandran, Loc H. Dao
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Patent number: 5453559Abstract: A hybrid condensation-absorption process and unit is disclosed for the recovery of olefins. A mixed-component stream containing hydrogen, methane and olefins is compressed and refrigerated against propylene refrigerant to partially condense the stream. The condensate is stripped of volatile components and fed to a fractionation unit such as a deethanizer. The volatile components stripped from the condensate and the non-condensed vapor from the mixed-component stream are fed to a solvent absorption unit to remove olefins which are absorbed in the solvent. The olefins-rich solvent is regenerated to recover olefins and lean solvent. The lean solvent is recirculated to the absorption unit. The olefins recovered from regeneration of the solvent are fed to the fractionation unit along with the pre-stripped condensate. Vapor from the absorption unit is cryogenically processed to recover a crude hydrogen product, a fuel gas product and residual olefins which can be recycled to the absorption unit.Type: GrantFiled: April 1, 1994Date of Patent: September 26, 1995Assignee: The M. W. Kellogg CompanyInventors: Christopher L. Phillips, Vijender K. Verma
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Patent number: 5444176Abstract: A safe, effective, and economical method is provided for recovering olefins from cat-cracked gases without accumulating dangerous amounts of nitrogen oxides. A stream of cat-cracked gas first is scrubbed to remove acid gases, including nitrogen dioxide (NO.sub.2), and then is passed through a depropanizer fractionation tower. Hydrocarbons having four or more carbon atoms are recovered in the bottoms of the depropanizer, and the overhead from the depropanizer--which is composed of hydrocarbons having three or fewer carbon atoms--is sent to an absorber demethanizer tower. Hydrocarbons having two or more carbon atoms are recovered in the bottoms from the absorber demethanizer tower, where temperatures are no lower than about -45.56.degree. C. (-50.degree. F.). The overhead from the absorber demethanizer tower--which is composed of methane, hydrogen, and trace amounts of nitrogen oxide, C.sub.2, and absorbent (C.sub.3)--then is chilled to condense and recover trace amounts of C.sub.Type: GrantFiled: October 28, 1992Date of Patent: August 22, 1995Assignee: Exxon Chemical Patents Inc.Inventors: Dane C. Grenoble, Roy T. Halle, William D. Thomson
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Patent number: 5414168Abstract: Purified hydrogen is recovered from the effluent of a catalytic dehydrogenation zone using an integrated cold absorption process. The effluent, which contains olefinic hydrocarbons and hydrogen is compressed, cooled and contacted with a liquid absorbent. The purified hydrogen can be recycled to the dehydrogenation zone and the olefinic hydrocarbons are recovered as product. The present invention will recover higher purity hydrogen and liquefiable hydrocarbons more economically than prior art processes.Type: GrantFiled: May 6, 1993Date of Patent: May 9, 1995Assignee: UOPInventor: Norman H. Scott
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Patent number: 5386076Abstract: The present invention provides a method for separating conjunct polymers which are formed as byproducts of acid catalyzed isoparaffin-olefin alkylation and sulfolane from a mixture containing conjunct polymers, sulfolane, and hydrofluoric acid, which method provides a sulfolane recycle stream which requires no further drying before charging the stream to the alkylation reaction zone.Type: GrantFiled: August 23, 1993Date of Patent: January 31, 1995Assignee: Mobil Oil CorporationInventors: Jonathan E. Child, Tomas R. Melli
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Patent number: 5345025Abstract: A process for the separation and recovery of the product stream resulting from the dehydrogenation of dehydrogentable hydrocarbons which process utilizes an integrated system for the recovery of liquid olefin product by use of a compression system, a pressure swing adsorption unit and a chiller system to concentrate the olefin poroduct.Type: GrantFiled: December 21, 1992Date of Patent: September 6, 1994Assignee: UOPInventors: Michael J. Mitariten, Norman H. Scott
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Patent number: 5336827Abstract: There are disclosed a process for producing an oligomer by oligomerizing a raw material comprising an unsaturated bicyclo heptane derivative and/or an unsaturated bicyclo octane derivative, which comprises the step of restricting the contents of dienes contained in the raw material to at most 1% by weight; and a process wherein the raw material is subjected to solid acid treatment simultaneously with or prior to distillation and then to oligomerization. The above process can efficiently produce the oligomer well suited for use in a traction drive fluid having a low viscosity and exhibiting excellent performance over a wide temperature range.Type: GrantFiled: June 21, 1993Date of Patent: August 9, 1994Assignee: Idemitsu Kosan Co., Ltd.Inventors: Takashi Ohno, Toshiyuki Tsubouchi
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Patent number: 5326929Abstract: A continuous process is described for contacting an olefins-containing feed gas stream, which has been freed of CO.sub.2 and sulfur compounds, compressed, cooled, and dried, with a solvent in an intercooled and reboiled demethanizing absorber to produce a rich solvent bottom stream containing ethylene and heavier hydrocarbons and an absorber overhead stream which is fed to a methane absorber which recovers a hydrogen product stream as overhead and produces a rich solvent stream as bottoms. When recovering up to 50% of the incoming hydrogen, this rich solvent stream from the methane absorber is fed to the demethanizing absorber, but when recovering from 20% to 100% of the incoming hydrogen, this rich solvent stream is recycled in part to the demethanizing absorber and in part is fed to a methane stripper which sends its bottoms to the methane absorber and its overhead to an auto refrigerated recovery unit which removes H.sub.2, CH.sub.4, and CO as a fuel gas product and produces an ethylene and heavier stream.Type: GrantFiled: August 31, 1992Date of Patent: July 5, 1994Assignee: Advanced Extraction Technologies, Inc.Inventors: Yuv R. Mehra, Wilfred K. Lam, Dow W. Mullins
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Patent number: 5304693Abstract: A process for the elimination of mercury from an overall steam cracking installation, characterized in that regeneration is terminated by the injection of regeneration gas onto an active demercurizing mass, such that there is substantially no trace of mercury in the air or liquids leaving the installation. The process involves the use of three demercurizing masses, namely two upstream of the installation which are in series and one downstream, which latter is demercurized by at least one of the upstream masses. The use more particularly applies to the depollution of steam cracking installations which are already polluted by mercury.Type: GrantFiled: August 28, 1991Date of Patent: April 19, 1994Assignee: Institut Francais du PetroleInventors: Jean-Paul Boitiaux, Patrick Sarrazin
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Patent number: 5300715Abstract: An improved process for the production of linear olefinic hydrocarbons by paraffin dehydrogenation and adsorptive separation is disclosed. Aromatic by-products normally formed in paraffin dehydrogenation are selectively removed using at least one aromatics removal zone. Removal of these aromatic by-products significantly increases the purity of the olefinic hydrocarbon product and increases the capacity of the adsorptive separation zone. The improved process is believed to increase the life of the adsorbent in the adsorptive separation zone and the life of the catalyst in the dehydrogenation zone.Type: GrantFiled: October 9, 1992Date of Patent: April 5, 1994Assignee: UOPInventor: Bipin V. Vora
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Patent number: 5288370Abstract: For the separation of butenes and butanes by extractive distillation, a charge mainly containing butenes and butanes is contacted in an extractive distillation column under pressure with a first selective polar solvent, S1 (e.g., dimethyl formamide), the butanes being collected at the top. The solvent S1 containing the butenes and passing out at the bottom is mixed with a second solvent, S2, having a boiling point intermediate between that of butenes and that of the solvent S1, the mixture passing into a desorption column under pressure, where the butenes are collected at the top. The mixture of solvent S1 and S2 is separated in a purification column under atmospheric pressure, the solvent S2 passing out at the top is recycled to the desorption column, and the solvent S1 passing out at the bottom is recycled to the extractive distillation column.Type: GrantFiled: March 20, 1992Date of Patent: February 22, 1994Assignee: Institut Francais Du PetroleInventors: Lionel Asselineau, Alexandre Rojey
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Patent number: 5242550Abstract: For the separation of butanes and butenes by extractive distillation, a charge mainly containing butanes and butenes is contacted in an extractive distillation column under pressure with a polar solvent (e.g., dimethyl formamide), the butanes being collected at the head. The solvent containing the butenes passes into a second column under pressure, where the butenes are partly desorbed and collected at the head. The solvent still containing butenes is purified in a third column under atmospheric pressure and the solvent-containing vapor distillate thereof is returned, after compression, to the lower part of the second column.Type: GrantFiled: February 26, 1992Date of Patent: September 7, 1993Assignee: Institut Francais du PetroleInventors: Lionel Asselineau, Paul Mikitenlo
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Patent number: 5227567Abstract: A process for the separation and recovery of the product stream resulting from the dehydrogenation of dehydrogenatable hydrocarbons which process utilizes a chiller system for the recovery of olefin product liquid and a pressure swing adsorption unit to concentrate the olefin product liquid which is not recovered by the chiller.Type: GrantFiled: January 27, 1992Date of Patent: July 13, 1993Assignee: UOPInventors: Michael J. Mitariten, Norman H. Scott
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Patent number: 5220097Abstract: A continuous process is described for contacting an olefins-containing feed gas stream, freed of CO.sub.2 and sulfur compounds, in a front-end heat-pumped depropanizer to remove the C.sub.Type: GrantFiled: February 19, 1992Date of Patent: June 15, 1993Assignees: Advanced Extraction Technologies, Inc., Kinetic Technology International Corp.Inventors: Wilfred K. Lam, Yuv R. Mehra, Don W. Mullins
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Patent number: 5191150Abstract: A method for separating conjunct polymers and sulfolane from a mixture containing conjunct polymers, sulfolane, and hydrofluoric acid is disclosed, which method comprises the sequential steps of separating hydrofluoric acid from said mixture to provide an intermediate stream containing less than about 30 percent hydrofluoric acid by weight and gravitationally separating said intermediate stream into a sulfolane-enriched stream and a conjunct polymer-enriched stream.Type: GrantFiled: February 11, 1992Date of Patent: March 2, 1993Assignee: Mobil Oil CorporationInventors: Jonathan E. Child, Tomas R. Melli, Sergei Yurchak
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Patent number: 5177293Abstract: A process for the separation and recovery of the products stream resulting from the dehydrogenation of dehydrogenatable hydrocarbons which process utilizes an integrated system for the recovery of liquid olefin product by the use of a compression system, a pressure swing adsorption unit and a chiller system to concentrate the olefin product.Type: GrantFiled: April 10, 1992Date of Patent: January 5, 1993Assignee: UOPInventors: Michael J. Mitariten, Norman H. Scott
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Patent number: 5154802Abstract: The separation of alkadienes from close-boiling alkenes by extractive distillation employs as solvent either N-(.beta.-mercaptoethyl)-2-pyrrolidone alone, or a mixture of N-(.beta.-mercaptoethyl)-2-pyrrolidone and either N-methyl-2-pyrrolidone or cyclohexanol, or a mixture of cyclohexanol and tetraethylene glycol. The separation of cycloalkadines from close-boiling alkadienes by extractive distillation employs N-(.beta.-mercaptoethyl)-2-pyrrolidone as solvent.Type: GrantFiled: July 17, 1991Date of Patent: October 13, 1992Assignee: Phillips Petroleum CompanyInventors: Fu-Ming Lee, Ronald E. Brown
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Patent number: 5085740Abstract: An extractive distillation process for separating at least one C.sub.4 -C.sub.10 alkene (monoolefin) from at least one close-boiling alkane (paraffin) employs as solvent a mixture of (a) at least one N-alkyl-2-pyrrolidone, preferably N-methyl-2-pyrrolidone and either (b1) at least one sulfolane compound (preferably cyclotetramethylene sulfone) or (b2) at least one glycol compound (preferably tetraethylene glycol) or both (b1) and (b2).Type: GrantFiled: October 26, 1990Date of Patent: February 4, 1992Assignee: Phillips Petroleum CompanyInventors: Fu-Ming Lee, Ronald E. Brown
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Patent number: 4946560Abstract: A feedstock containing alpha olefins and internal olefins is converted into a first product having an enhanced internal olefin content over that of the feedstock and into a second product having an enhanced alpha olefin content over that of the feedstock by:(a) contacting the feedstock with an anthracene at a temperature ranging from 150.degree. to 275.degree. C. to form an olefin adduct with anthracene,(b) separating the adduct from the product of step (a) to leave a first product enriched in internal olefin,(c) heating the separated adduct at a temperature of from 250.degree.-400.degree. C. to produce anthracene and an olefin product enriched in alpha olefin, and(d) separating anthracene from the product of step (c) to produce a second product enriched in alpha olefin. Linear olefins are preferred feedstocks.Type: GrantFiled: October 27, 1988Date of Patent: August 7, 1990Assignee: Shell Oil CompanyInventors: Lynn H. Slaugh, Howard L. Fong
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Patent number: 4943671Abstract: Organic halogen compounds in which one or more halogen atoms are covalently bonded to the carbon are subjected to reductive dehalogenation by reaction with a hydrocarbon in the presence of carbon at elevated temperatures with formation of a hydrogen halide, by a process in which the dehalogenation is carried out in the presence of iron powder or an iron compound as a cocatalyst, at from 100.degree. to 450.degree. C.Type: GrantFiled: May 2, 1988Date of Patent: July 24, 1990Assignee: BASF AktiengesellschaftInventors: Toni Dockner, Manfred Sauerwald, Herbert Krug, Matthias Irgang
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Patent number: 4933499Abstract: The invention relates to a process for the purification of alkenyl aromatic compounds which contain benzaldehyde as an impurity. This process comprises steps for contacting a benaldehyde-containing alkenyl aromatic compound with a bisulphite treating agent, and separating the resulting benzaldehyde-bisulphite addition product from the alkenyl aromatic compound. In certain preferred embodiments, the treating agent is a modified anion-exchange resin containing bound bisulphite ions. Optionally, the process then further comprises a step for recovering the benzaldehyde from the resin addition product by contact with an aqueous sodium carbonate solution or by steam distillation.Type: GrantFiled: February 27, 1989Date of Patent: June 12, 1990Assignee: Shell Oil CompanyInventors: Paul A. M. Grotenhuis, Brian L. Goodall