With Plural Separation Procedures Patents (Class 585/450)
  • Patent number: 6096935
    Abstract: A process for producing alkyl aromatics using a transalkylation reaction zone and an alkylation reaction zone is disclosed. The transalkylation reaction zone effluent passes to the alkylation reaction zone where aromatics in the transalkylation reaction zone effluent are alkylated to the desired alkyl aromatics. This process decreases the capital and operating costs of recycling the aromatics in the transalkylation reaction zone effluent. This process is well suited for solid transalkylation and alkylation catalysts. Ethylbenzene and cumene may be produced by this process.
    Type: Grant
    Filed: July 28, 1998
    Date of Patent: August 1, 2000
    Assignee: UOP LLC
    Inventors: Russell C. Schulz, Gregory J. Gajda
  • Patent number: 6069285
    Abstract: An integrated alkylaromatic process using a solid alkylation catalyst and an aromatic rectifier is disclosed for alkylating aromatics with olefins and for regenerating the solid alkylation catalyst. The aromatic rectifier produces a relatively low-purity aromatic-containing overhead stream that is used in producing alkylaromatics, and an aromatic column produces a relatively high-purity aromatic-containing overhead stream that is used in regenerating the solid alkylation catalyst. In another embodiment, this process is further integrated with a paraffin dehydrogenation zone and an aromatic by-products removal zone. This invention produces the benzene-containing streams that are necessary for alkylating and for regenerating in a more economical manner than prior art processes.
    Type: Grant
    Filed: June 9, 1999
    Date of Patent: May 30, 2000
    Assignee: UOP LLC
    Inventors: Thomas R. Fritsch, Steven F. Eshelman, Dennis E. O'Brien
  • Patent number: 6013848
    Abstract: A process for the conversion of heavy bottoms from aromatic alkylation known as "flux oil" and containing heavier polyalkylaromatic compounds, in which the heavier polyalkylates are fed along with aromatic to a reactor containing an acidic zeolite catalyst for conversion to light mono-, and poly alkylaromatic compounds. The light polyalkylates may then be transalkylated with benzene to form additional monoalkylate.
    Type: Grant
    Filed: July 8, 1997
    Date of Patent: January 11, 2000
    Assignee: Catalytic Distillation Technologies
    Inventors: Jamin Chen, Chuen Y. Yeh
  • Patent number: 6008422
    Abstract: A process for producing alkylaromatics using a multibed alkylation reaction zone is disclosed. The alkylation reaction zone effluent is divided into three portions, the first being recirculated to the inlet of the reaction zone, the second being cooled and recirculated to one or more other beds in the reaction zone, and the third being passed to a product recovery zone where the alkylaromatic is recovered. This process insures that all of the catalyst beds operate in an optimum temperature range. This in turn insures that byproduct formation is minimized and catalyst life is maximized. Ethylbenzene and cumene may be produced by this process.
    Type: Grant
    Filed: July 7, 1998
    Date of Patent: December 28, 1999
    Assignee: UOP LLC
    Inventors: Russell C. Schulz, Perry K. Ho
  • Patent number: 5998684
    Abstract: A separation arrangement for a cumene process that operates with a relatively wet feed to an alkylation zone and relatively dry feed to a transalkylation zone reduces utilities and capital expenses for the separation and recycle of distinct wet and dry components by using an arrangement that first separates effluent from the trans alkylation and alkylation reaction zone in a benzene column before performing light ends and drying in a downstream depropanizer column. The arrangement uses a portion of the net overhead stream from the benzene column as a wet recycle stream for return to the alkylation reaction zone and sends another portion of the benzene net overhead to the depropanizer to supply a dry benzene recycle for the trans alkylation reaction zone.
    Type: Grant
    Filed: November 10, 1997
    Date of Patent: December 7, 1999
    Assignee: UOP LLC
    Inventors: Perry K. Ho, Russell C. Schulz
  • Patent number: 5962758
    Abstract: Ethylbenzene is produced from benzene and ethylene in an alkylation reactor wherein the feedstocks also contain propylbenzenes and/or components that produce propylbenzene. Polyethylbenzenes are also produced in the process. The ethylbenzene product and unreacted benzene are separated and then the propylbenzenes are separated from the polyethylbenzenes by distillation. The propylbenzenes are destroyed in a vapor-phase reactor and the polyethylbenzenes are transalkylated with benzene in a liquid or partial liquid phase at a lower temperature.
    Type: Grant
    Filed: April 9, 1998
    Date of Patent: October 5, 1999
    Assignee: ABB Lummus Global Inc.
    Inventors: Angel S. Sy, Richard J. Wilcox
  • Patent number: 5959168
    Abstract: A zeolite-based ethylbenzene process which is suitable for retrofitting aluminum chloride-based ethylbenzene plants. The process involves alkylating benzene with ethylene in an alkylation zone in the presence of zeolite beta or Y or an MCM zeolite so as to produce an alkylation product mixture containing benzene, ethylbenzene, and polyethylbenzenes which can be separated in the aromatics recovery (distillation) stage of an aluminum chloride-based plant. The polyethylbenzenes are subsequently contacted with benzene in a transalkylation zone using zeolite beta or mordenite or Y so as to produce a transalkylation product mixture which is also separable in the aromatics recovery stage of an aluminum chloride-based plant.
    Type: Grant
    Filed: February 17, 1998
    Date of Patent: September 28, 1999
    Assignee: The Dow Chemical Company
    Inventors: Matheus J. M. van der Aalst, Mohammed S. U. Samson, Garmt R. Meima, Michael Q. de Steenwinkel
  • Patent number: 5955642
    Abstract: An alkylation/transalkylation process involving vapor phase alkylation of a benzene feedstock in a multi-stage alkylation zone having a plurality of series connected catalyst beds containing a pentasil aromatic alkylation catalyst, such as silicalite, coupled with intermediate separation and recirculation steps and liquid phase transalkylation over a transalkylation catalyst comprising a molecular sieve having a pore size greater than the pore size of the silicalite. The benzene containing feedstock is supplied to the multi-stage alkylation reaction zone along with a C.sub.2 -C.sub.4 alkylating agent operated under temperature and pressure conditions to maintain the benzene in the gas phase. Alkylated product is recovered from the alkylation zone and supplied to a benzene recovery zone for the separation of the benzene from the alkylation product. Benzene from the benzene recovery zone is recycled to the reaction zone.
    Type: Grant
    Filed: October 30, 1996
    Date of Patent: September 21, 1999
    Assignee: Fina Technology, Inc.
    Inventors: James T. Merrill, James R. Butler
  • Patent number: 5900518
    Abstract: The present invention addresses heat integration in an alkylation/transalkylation process involving alkylation of an aromatic substrate with a C.sub.2 -C.sub.4 alklating agent coupled with separation to recover a monoalkylated aromatic product and liquid phase transalkylation of a polyalkylated product. Aromatic feedstock and a C.sub.2 -C.sub.4 alkylating agent are supplied to an alkylation reaction zone which is operated to produce an alkylated product. The output from the alkylation reaction zone initially travels through an arrangement of heat exchangers. From there, the alkylation effluent passes into the first separation zone which is operated to produce a lower boiling fraction comprising the aromatic substrate, which may be recycled to the alkylation reaction zone, and a higher boiling fraction comprising a mixture of monoalkylated and polyalkylated aromatics.
    Type: Grant
    Filed: October 30, 1996
    Date of Patent: May 4, 1999
    Assignee: Fina Technology, Inc.
    Inventors: James T. Merrill, Joseph Honn Tudor
  • Patent number: 5877370
    Abstract: Reduction of the amount of 1,1-diphenylethane formed in the production of ethylbenzene by alkylation of benzene with ethylene can be effected by alkylating at a low concentration of ethylene. This invention allows operation at a low molar ratio of phenyl groups per ethyl group and leads to a product containing less than 1.0 wt-% 1,1-diphenylethane relative to ethylbenzene. This invention is applicable to processes for the production of a wide variety of other commercially important alkylated aromatics.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: March 2, 1999
    Assignee: UOP LLC
    Inventor: Gregory J. Gajda
  • Patent number: 5877384
    Abstract: An apparatus and process for separating propane and benzene from alkylation reaction products in cumene production. An integrated fractionation tower combines the functions of propane separation, recycle benzene recovery as well as system dewatering to eliminate the need for separate depropanizer and dehydration columns and thus save capital and operating expenses.
    Type: Grant
    Filed: February 12, 1996
    Date of Patent: March 2, 1999
    Assignee: The M. W. Kellogg Company
    Inventors: Harold Edward Gimpel, Eric Wing-Tak Wong, Kourosh Faiz Ghassemi
  • Patent number: 5856606
    Abstract: Paraffins or other hydrocarbons are alkylated in a process featuring a reaction zone containing a pool of liquid maintained at its boiling point and containing a suspended solid catalyst, which allows the heat of reaction to vaporize a portion of the liquid phase feed hydrocarbon. The vapor phase withdrawn from the top of the reaction zone is at least partially recycled to the reaction zone either as vapor or liquid. The feed hydrocarbons are introduced to the bottom of the reaction zone as a vapor phase stream, which may contain hydrogen. The catalyst is suspended within the liquid in the reaction zone.
    Type: Grant
    Filed: September 27, 1996
    Date of Patent: January 5, 1999
    Assignee: UOP LLC
    Inventor: Anil R. Oroskar
  • Patent number: 5847253
    Abstract: A process for the production of alkylaromatic hydrocarbons that operates with a high water content in an alkylation zone and a low water content in a transalkylation zone is disclosed. An aromatic feed and an acyclic feed are first passed through the alkylation reaction zone that operates at a high water content. A stripping column receives the effluent of the alkylation reaction zone, removes water and unreacted aromatic feed and produces a bottom stream containing unreacted aromatic feed and alkylated aromatics. A recycle column receives the bottom stream and produces an overhead stream of unreacted aromatic feed having a low water content. The overhead stream and a stream of polyalkylated aromatics are contacted in the transalkylation zone.
    Type: Grant
    Filed: March 18, 1997
    Date of Patent: December 8, 1998
    Assignee: UOP LLC
    Inventors: Perry K. Ho, Constante P. Tagamolila
  • Patent number: 5744670
    Abstract: A process for producing alkylnaphthalene from a feedstock comprising isomers of dialkylnaphthalene and naphthalene by contacting the feedstock with a catalyst composition, in which the process comprising transalkylation between isomers of dialkylnaphthalene and naphthalene to produce monoalkylnaphthalene, and isomerization of dialkylnaphthalene, wherein the catalyst composition comprising a synthetic zeolite characterized by an X-ray diffraction pattern including interplanar d-spacing as set forth in Table A of the specification.
    Type: Grant
    Filed: June 10, 1996
    Date of Patent: April 28, 1998
    Assignees: Kobe Steel, Ltd., Mobil Oil Corporation
    Inventors: Masahiro Motoyuki, Koji Yamamoto, John Paul McWilliams, Robert Glenn Bundens
  • Patent number: 5690809
    Abstract: An improved process is provided for in situ mitigation of coke buildup and porous catalyst used for the processing of hydrocarbon feed stocks. The process exhibits improved catalyst activity over extended periods and the process comprises the pretreatment of hydrocarbon feed stocks to reduce impurities in the feed stocks in the form of peroxides and oxygen compounds that promote the formation of coke precursors, which precursors are typically in the form of olefinic oligomers. The process includes contacting the pretreated feed stream with a suitable catalyst under sub-critical, near-critical and supercritical conditions.
    Type: Grant
    Filed: April 18, 1996
    Date of Patent: November 25, 1997
    Assignee: Center for Research, Inc.
    Inventors: Bala Subramaniam, Said Saim, Michael C. Clark
  • Patent number: 5600049
    Abstract: In the alkylation of benzene with propylene in a distillation column reactor to produce cumene the overheads from the distillation reactor are fed to a depropanizer where the unreacted benzene is separated from C.sub.3 's. Liquid propylene feed for the distillation column reactor is vaporized by indirect heat exchange with the overheads from the depropanizer to condense the overheads, thereby reducing the pressure in the depropanizer below what would be normally achieved with conventional condensing systems.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: February 4, 1997
    Assignee: Chemical Research & Licensing Company
    Inventor: Angel Sy
  • Patent number: 5489732
    Abstract: Hydrocarbons are alkylated in a fluidized riser-reactor using a solid catalyst which is regenerated within the process by contact with hydrogen. The alkylation and regeneration steps are separated to prevent the admixture of hydrogen and any olefins present in the process. Two separate modes of regeneration are performed simultaneously: a mild liquid-phase washing and a vapor-phase hot hydrogen stripping operation.
    Type: Grant
    Filed: October 14, 1994
    Date of Patent: February 6, 1996
    Assignee: UOP
    Inventors: Scott Y. Zhang, Christopher D. Gosling, Paul A. Sechrist, Gregory A. Funk
  • Patent number: 5362377
    Abstract: Ethers suitable for use as high octane oxygenate additives for motor fuels are produced by a catalytic distillation process wherein a mixture of C.sub.4 -plus isoolefin(s) and an alcohol are recovered from a catalytic distillation zone as an overhead stream and charged to a packed liquid-phase reaction zone containing an etherification catalyst before being recycled to one or more portions of the overall catalytic distillation zone. The process is useful in the coprocessing of a mixture of isobutylene and isoamylene and in other hydrocarbon conversion processes such as hydration and alkylation.
    Type: Grant
    Filed: September 13, 1993
    Date of Patent: November 8, 1994
    Assignee: UPO
    Inventor: Terry L. Marker
  • Patent number: 5336821
    Abstract: A process for the alkylation of aromatic hydrocarbons such as cumene and ethylbenzene is disclosed. A portion of the effluent stream from an alkylation reactor passes through an indirect heat exchanger to transfer heat to a flashed stream containing the product aromatic hydrocarbons. The heat exchanger recovers the exothermic heat of reaction from the effluent stream for use elsewhere in the process. This method of heat exchange is especially useful in alkylation processes where the temperature of the effluent stream is relatively low, such as where the alkylation reactor contains a zeolite catalyst.
    Type: Grant
    Filed: May 6, 1993
    Date of Patent: August 9, 1994
    Assignee: UOP
    Inventors: Richard R. DeGraff, Peter J. Van Opdorp, Russell C. Schulz
  • Patent number: 5185486
    Abstract: The benzene content of hydrocarbon gasolines is accomplished by (a) fractionating at least one hydrocarbon gasoline into a light fraction A, with an increased benzene content, and a heavy fraction B, with a reduced benzene content; (b) contacting the light fraction A at a temperature below room temperature with a gas containing at least a fraction of olefins in which the number of carbon atoms is from 2 to 5 per molecule so that at least a fraction of said olefins is absorbed in light fraction A; at the end of stage (b), separating a residual gas with a reduced olefin content from a liquid fraction C, with an increased olefin content; (d) passing the fraction C from stage (c) into an alkylation reactor so that at least a fraction of the benzene is alkylated by at least a fraction of the olefins; (e) fractionating the mixture emerging from stage (d) so as to produce, firstly, a gas phase chiefly comprising gases which were not converted during stage (d) and, secondly, a liquid phase, at least partly containing
    Type: Grant
    Filed: August 21, 1990
    Date of Patent: February 9, 1993
    Assignee: Institut Francais du Petrole
    Inventors: Jean-Claude Collin, Bernard Juguin, deceased, Joseph Larue, Alexandre Rojey
  • Patent number: 5177283
    Abstract: Alkylaromatic hydrocarbons are produced in a process which comprises concentrating a feed aromatic hydrocarbon into a sidecut stream removed from a fractionation column. A feed acyclic olefin is then admixed with the aromatic hydrocarbon and passed through an alkylation reaction zone operated at optimum alkylation conditions. The reaction zone effluent is returned to the fractionation column to recover the product and to recycle untreated feed aromatics. This technique can be applied to hydrocarbon conversion processes in general to obtain benefits of catalytic distillation while operating the reaction zone at conditions not suitable for catalytic distillation. Hydrogen and other light gases are preferably separated from the reaction zone effluent by cooling and vapor-liquid separation external to the column.
    Type: Grant
    Filed: February 3, 1992
    Date of Patent: January 5, 1993
    Assignee: UOP
    Inventor: Dennis J. Ward
  • Patent number: 5138113
    Abstract: The invention relates to a process for producing alkylaromatic hydrocarbons from natural gas containing methane, characterized in that it comprises the following three successive stages:1) thermal cracking of the natural gas with forming of hydrogen and C.sub.2.sup.30 hydrocarbons, particularly ethylene and acetylene,2) separation of the C.sub.2.sup.+ hydrocarbons, particularly of the ethylene and the acteylene, obtained at the end of stage 1), by cooled absorption in a solvent,3) conversion of the C.sub.2.sup.+ hydrocarbons from stage 2) into alkylaromatics.The obtained alkylaromatics can be used as a base for premium gasoline.
    Type: Grant
    Filed: November 27, 1990
    Date of Patent: August 11, 1992
    Assignee: Institut Francais du Petrole
    Inventors: Bernard A. Juguin, Jean-Claude P. S. Collin, Joseph Y. M. Larue, Christian R. Busson
  • Patent number: 5118872
    Abstract: There is provided a new process for conducting heterogeneous chemical reactions in which a particulate catalyst is slurried in one of the reactant streams and fed into a distillation column reactor in a distillation reaction zone. The distillation reaction zone contains inert packing which provides the distillation structure for separation. The slurried catalyst trickles downward through the inert packing and is removed with the bottoms and separated therefrom for regeneration or replacement.
    Type: Grant
    Filed: April 4, 1991
    Date of Patent: June 2, 1992
    Assignee: Chemical Research & Licensing Company
    Inventors: Lawrence A. Smith, Jr., John R. Adams
  • Patent number: 5105041
    Abstract: A process for the production of alkylaromatic hydrocarbons uses a working fluid to reduce the costs of separating an unreacted aromatic feed substrate from aromatic hydrocarbon products. Unreacted aromatic substrate is combined with a light hydrocarbon, such as propane, to form a combined effluent stream. The combined effluent stream enters a flash separator where unreacted aromatic substrate is lifted overhead with the light hydrocarbon while heavier aromatic products are recovered below. The aromatic substrate and light hydrocarbon are easily separated in a simple separation zone. Lifting the aromatic substrate with the working fluid reduces the volume of aromatic substrate that remains with the aromatic product so that the more energy intensive separation of the aromatic substrate and aromatic product is performed on a reduced volume of material.
    Type: Grant
    Filed: September 10, 1990
    Date of Patent: April 14, 1992
    Assignee: UOP
    Inventors: Don L. Ferk, Eugene Schmelzer, Edward C. Haun
  • Patent number: 5019669
    Abstract: Organic aromatic compounds are alkylated in a Reactive Distillation.TM. reactor, wherein the solid particulate catalyst is slurried in the aromatic feed stream and fed to a reaction zone containing inert distillation packing. Olefin is vaporized and fed to the bottom of the reaction zone and agitates the catalyst while reacting the olefin with the aromatic to form an alkylation product. The alkylation product is removed from the lower end of the reaction zone and recovered. Any unreacted aromatic is distilled overhead and recycled or recovered. Recycling the aromatic controls the molar ratio of aromatic to olefin to the extent that substantially all of the olefin is reacted.
    Type: Grant
    Filed: March 10, 1989
    Date of Patent: May 28, 1991
    Assignee: Chemical Research & Licensing Company
    Inventors: John R. Adams, Lawrence A. Smith
  • Patent number: 4950824
    Abstract: A process for the production of 2,6-diisopropylnaphthalene is disclosed wherein an isopropylation reaction mixture containing isopropylated naphthalenes is subjected to transalkylation with a triisopropylnaphthalene-containing mixture to obtain a mixture containing mono-, di- and tri-isopropylnaphthalenes which is then separated into a first fraction containing monisopropylnaphthalenes, a second fraction containing diisopropylnaphthalenes and a third fraction containing triisopropylnaphthalenes. The first and third fractions are recycled to the above system, while the second fraction is subjected to separation treatments for the recovery of 2,6-diisopropylnaphthalene. The second fraction from which 2,6-diisopropylnaphthalene has been removed is subjected to transalkylation with naphthalene to obtain a monoisopropylnaphthalene-rich mixture which is to be fed to the isopropylation step.
    Type: Grant
    Filed: August 2, 1989
    Date of Patent: August 21, 1990
    Assignees: Chiyoda Corporation, NKK Corporation
    Inventors: Yoshimi Shiroto, Mitsunori Shimura, Kenji Shimokawa, Yoshio Fukui, Sachio Asaoka, Hiroto Tajima, Kazuaki Ueda, Yakudo Tachibana, Kazuhiko Tate, Hiroaki Taniguchi
  • Patent number: 4950834
    Abstract: Cumene is produced in a catalytic distillation column reactor having an upper bed of Omega type molecular sieve catalyst and a lower bed of Y type molecular sieve catalyst. Benzene and propylene are reacted in the upper bed where the Omega type sieve is more selective to cumene that the Y type sieve. Part of the reaction mixture flows down the column to the Y bed where benzene reacts with any unreacted propylene to produce cumene. Additionally, benzene reacts with dipropylbenzene in the Y bed to produce more cumene. Cumene is recovered as bottoms product and unreacted benzene recovered as overheads where it may be returned as reflux to the column to control the mole ratio of benzene to propylene.
    Type: Grant
    Filed: July 26, 1989
    Date of Patent: August 21, 1990
    Inventors: Robert P. Arganbright, Dennis Hearn
  • Patent number: 4885424
    Abstract: A process for the production of alkylaromatic hydrocarbons uses a light hydrocarbon recycle to reduce the costs of separating an unreacted aromatic feed substrate from aromatic hydrocarbon products. Unreacted aromatic substrate is combined with a light hydrocarbon, such as propane, to form a combined effluent stream. The combined effluent stream enters a flash separator where unreacted aromatic substrate is lifted overhead with the light hydrocarbon while heavier aromatic products are recovered below. The aromatic substrate and light hydrocarbon are easily separated in a simple separation zone. Lifting the aromatic substrate with the light hydrocarbon reduces the volume of aromatic substrate that remains with the aromatic product so that the more energy intensive separation of the aromatic substrate and aromatic product is performed on a reduced volume of material.
    Type: Grant
    Filed: February 5, 1988
    Date of Patent: December 5, 1989
    Assignee: UOP
    Inventors: Don L. Ferk, Eugene Schmelzer, Edward C. Haun
  • Patent number: 4695665
    Abstract: A process flow is presented for a hydrocarbon conversion process in which a relatively volatile hydrocarbon is separated from less volatile feed and product hydrocarbons present in a reaction zone effluent stream. The preferred usage is in the alkylation of benzene with propylene. The reaction zone effluent stream is passed into a lower portion of a rectified separation zone. Recycle aromatic hydrocarbon is passed into a contact exchanger/absorber present in the top portion of the rectified separation zone. The liquid collected at the bottom of the contact exchanger is removed as a sidecut stream and passed into the reaction zone.
    Type: Grant
    Filed: July 2, 1986
    Date of Patent: September 22, 1987
    Assignee: UOP Inc.
    Inventor: Richard R. De Graff
  • Patent number: 4587370
    Abstract: A fractionation method is disclosed for the recovery of product alkylaromatic hydrocarbons produced by the alkylation of aromatic hydrocarbons. Three fractionation columns are employed in series. Aromatic feed hydrocarbons are recycled from the overhead of the first column, which is reboiled by the overhead vapor of the second column. The product alkylaromatic is recovered from the condensate produced in using the second column overhead as a heat source. The product alkylaromatic is also present in the bottoms of the second column which flows into a low pressure stripping column. The entire overhead vapor of the stripping column is compressed and passed into the lower portion of the second column.
    Type: Grant
    Filed: June 5, 1985
    Date of Patent: May 6, 1986
    Assignee: UOP Inc.
    Inventor: Richard R. DeGraff
  • Patent number: 4528412
    Abstract: A hydrocarbon conversion process for the production of C.sub.6 -C.sub.8 aromatic hydrocarbons from C.sub.3 and C.sub.4 aliphatic hydrocarbons is disclosed. This dehydrocyclodimerization process is characterized by the integrated product recovery steps employed to separate hydrogen and products from the reactor effluent. Following partial condensation of the reactor effluent stream, the resultant vapor is subjected to liquid absorption (scrubbing) followed by autorefrigeration to yield lighter gas streams. Liquids from the various steps are separated via fractionation.
    Type: Grant
    Filed: October 11, 1984
    Date of Patent: July 9, 1985
    Assignee: UOP Inc.
    Inventor: Paul C. Steacy
  • Patent number: 4237327
    Abstract: A process for the HF-catalyzed alkylation of aromatic hydrocarbons is disclosed. A first overhead vapor stream removed from a first fractionation column which is used to regenerate the liquid-phase HF is passed directly into an upper intermediate point of a second fractionation column. A hydrocarbon stream containing the feed aromatic hydrocarbon and the product hydrocarbon is separated from liquid-phase HF and is then passed into the second fractionation column. HF dissolved in the hydrocarbon stream is removed from the second column as part of a second overhead vapor stream.
    Type: Grant
    Filed: October 9, 1979
    Date of Patent: December 2, 1980
    Assignee: UOP Inc.
    Inventor: George R. Winter, III