Aromatic Permeate Patents (Class 585/819)
  • Patent number: 5135547
    Abstract: A facilitated liquid membrane for the separation of olefins from a gaseous feed stream comprises a porous support structure (10, 15) and a liquid membrane which comprises an aqueous solution containing a metal salt facilitator capable of coordinating with olefin gases, and an alkyl carbonate co-solvent. A process for the separation of olefins from gaseous feed streams comprises the steps of passing a gaseous feed stream over one side of a facilitated liquid membrane according to the present invention and collecting the olefins on the other side of the membrane.
    Type: Grant
    Filed: June 20, 1991
    Date of Patent: August 4, 1992
    Assignee: The Standard Oil Company
    Inventors: Dean T. Tsou, Marc W. Blachman
  • Patent number: 5120900
    Abstract: Raffinate yield from solvent extraction is improved when the extract phase recovered from the solvent extraction process is subjected to a membrane separation step wherein a saturates/1-ring aromatics rich retentate is produced and a 2+ ring aromatics rich permeate are produced and the saturates/1-ring aromatic rich retentate phase is recycled to the solvent extraction process.
    Type: Grant
    Filed: December 5, 1990
    Date of Patent: June 9, 1992
    Assignee: Exxon Research and Engineering Company
    Inventors: Tan-Jen Chen, James R. Sweet
  • Patent number: 5095171
    Abstract: The separation of aromatic hydrocarbons from mixtures of aromatic and non-aromatic hydrocarbon feeds under pervaporation conditions, is improved by the control of the amount of oxygen present in the feed. The amount of oxygen in the feed, such as heavy cat naphtha or other cracked feed, should be less than 30 wppm, preferably less than 10 wppm. The oxygen level in the feed can be controlled by the addition of small amount of oxygen scavenger into the feed. Hindered phenols are representative of useful oxygen scavengers.
    Type: Grant
    Filed: April 8, 1991
    Date of Patent: March 10, 1992
    Assignee: Exxon Research and Engineering Company
    Inventors: Joseph L. Feimer, Tan J. Chen
  • Patent number: 5095170
    Abstract: The yield, raffinate product quality, and throughput of the selective solvent extraction of hydrocarbon feeds is improved by subjecting the hydrocarbon feeds from which aromatic hydrocarbons are to be selectively solvent extracted to a membrane separation process which selectively permeates aromatics through the membranes to produce a permeate rich in aromatics and a retentate rich in saturates and 1-ring aromatics and subjecting this retentate to the selective solvent extraction process.
    Type: Grant
    Filed: December 5, 1990
    Date of Patent: March 10, 1992
    Assignee: Exxon and Research and Engineering Company
    Inventors: Tan-Jen Chen, James R. Sweet
  • Patent number: 5085778
    Abstract: A polyethylene imine membrane which has been cross-linked by heat treating at 100.degree. C.-200.degree. C. for 3-20 minutes may be used to dewater isopropanol or methyl ethyl ketone/toluene mixtures.
    Type: Grant
    Filed: January 22, 1991
    Date of Patent: February 4, 1992
    Assignee: Texaco Inc.
    Inventor: John Reale, Jr.
  • Patent number: 5063186
    Abstract: A new membrane for the separation of aromatic hydrocarbons from mixtures of said aromatic hydrocarbons and non-aromatic hydrocarbons has been prepared comprising a highly aromatic polyurethane membrane. These highly aromatic polyurea/urethane membranes are symmetric, dense film membranes made from the corresponding polyurea/urethane copolymers by standard membrane casting techniques. The polyurea/urethane copolymers are produced by reacting dihydroxy or polyhydroxy compounds, such as polyethers or polyesters having molecular weights in the range of about 500 to 5000 with aliphatic, alkylaromatic or aromatic diisocyanates or polyisocyanates and low molecular weight chain extenders, such as diamines, polyamines or amino alcohols.
    Type: Grant
    Filed: April 11, 1989
    Date of Patent: November 5, 1991
    Assignee: Exxon Research & Engineering Company
    Inventor: Robert C. Schucker
  • Patent number: 5055632
    Abstract: A new membrane for the separation of aromatic hydrocarbons from mixtures of said aromatic hydrocarbons and non-aromatic hydrocarbons has been prepared comprising a highly aromatic polyurea/urethane membrane. These highly aromatic polyurea/urethane membranes are symmetric, dense film membranes made from the corresponding polyurea/urethane copolymers by standard membrane casting techniques. The polyurea/urethane copolymers are produced by reacting dihydroxy or polyhydroxy compounds, such as polyethers or polyesters having molecular weights in the range of about 500 to 5000 with aliphatic, alkylaromatic or aromatic diisocyanates or polyisocyanates and low molecular weight chain extenders, such as diamines, polyamines or amino alcohols.
    Type: Grant
    Filed: December 29, 1989
    Date of Patent: October 8, 1991
    Assignee: Exxon Research & Engineering Company
    Inventor: Robert C. Schucker
  • Patent number: 5055631
    Abstract: The present invention describes a method for separating mixtures of aromatics and non-aromatics by permeation through a sulfonated polysulfone membrane which is selective for aromatics.
    Type: Grant
    Filed: July 11, 1990
    Date of Patent: October 8, 1991
    Assignee: Exxon Research & Engineering Company
    Inventors: Guido Sartori, W. S. Winston Ho, Robert E. Noone, Abraham D. Cohen
  • Patent number: 5045206
    Abstract: Multi-ring aromatic hydrocarbons and/or toxins are selectively solvent extracted from hydocarbon feed streams by the process comprising contacting the aromatics and/or toxins containing hydrocarbon stream with one side of a porous, non-selective partition barrier membrane while simultaneously contacting the other side of said membrane with an aromatics selective extraction solvent whereby the multi-ring aromatic hydrocarbons and/or toxins selectively migrate through the porous partition barrier membrane in response to the selective solvent. A preferred extraction solvent is ethylenediamine. The permeate comprising multi-ring aromatics in solvent can be subjected to a membrane separation process to separate the extraction solvent from the aromatics.
    Type: Grant
    Filed: December 5, 1990
    Date of Patent: September 3, 1991
    Assignee: Exxon Research & Engineering Company
    Inventors: Tan-Jen Chen, James R. Sweet
  • Patent number: 5019666
    Abstract: The present invention is a method for separating aromatics from saturates using a non-porous polycarbonate membrane. In a preferred embodiment, the polycarbonate membrane may be crosslinked.
    Type: Grant
    Filed: March 9, 1990
    Date of Patent: May 28, 1991
    Assignee: Exxon Research and Engineering Company
    Inventors: Guido Sartori, W. S. Winston Ho, David W. Savage, Robert E. Noone, Robert P. Mastondrea
  • Patent number: 5012035
    Abstract: The present invention describes a method for separating mixtures of aromatics and non-aromatics into aromatic-enriched and non-aromatic-enriched streams by contacting the mixture with one side of a polyphthalate-carbonate membrane and selectively permeating the aromatic components of the mixture through the membrane.
    Type: Grant
    Filed: July 11, 1990
    Date of Patent: April 30, 1991
    Assignee: Exxon Research and Engineering Company
    Inventors: Guido Sartori, W. S. Winston Ho, Robert E. Noone
  • Patent number: 5012036
    Abstract: The present invention describes a method for separating mixtures of aromatics and non-aromatics into aromatic-enriched and non-aromatic-enriched streams by contacting the aromatic/non-aromatics mixture with one side of a polyarylate membrane and selectively permeating the aromatic components through the membrane.
    Type: Grant
    Filed: July 11, 1990
    Date of Patent: April 30, 1991
    Assignee: Exxon Research and Engineering Company
    Inventors: Guido Sartori, W. S. Winston Ho, Robert E. Noone
  • Patent number: 4985138
    Abstract: Dewaxed oil containing dewaxing solvent from solvent dewaxing is treated by contact with a separating membrane to yield a retentate containing increased content of dewaxed oil and decreased content of dewaxing solvent and a permeate which contains increased content of dewaxing solvent and decreased content of dewaxing oil--the membrane including a polyimine layer which has been cross-linked with polyisocyanate or poly(carbonyl chloride).
    Type: Grant
    Filed: November 8, 1989
    Date of Patent: January 15, 1991
    Assignee: Texaco Inc.
    Inventor: Mordechai Pasternak
  • Patent number: 4975178
    Abstract: A process for catalytically reforming a gasoline boiling range hydrocarbonaceous feedstock wherein the reforming is conducted in two or more stages wherein each stage is separated from another stage by aromatics removal from the reaction stream of a preceding stage. Reforming in at least one of the downstream reactors is conducted in the presence of a catalyst comprised of a nobel metal, an inorganic support, and a promotor metal; or a catalyst comprised of a Group VIII metal on a type-X, type-Y, or type-L zeolitic support.
    Type: Grant
    Filed: October 2, 1989
    Date of Patent: December 4, 1990
    Assignee: Exxon Research & Engineering Company
    Inventors: Kenneth R. Clem, Kenneth J. Heider, James E. Kegerreis, Ehsan I. Shoukry
  • Patent number: 4962270
    Abstract: Improved separation of feed streams containing multiple components is effected by means of a multi membrane staged pervaporation process wherein each membrane stage is series is run as progressively higher temperature, stronger vacuum or both than the preceding stage. This process is especially useful for separating components from wide boiling range mixtures.
    Type: Grant
    Filed: February 27, 1989
    Date of Patent: October 9, 1990
    Assignee: Exxon Research and Engineering Company
    Inventors: Joseph L. Feimer, Robert C. Schucker, Charles P. Darnell
  • Patent number: 4962271
    Abstract: Membrane separation under perstraction conditions of a lube oil distillate is disclosed which produces a retentate rich in non-aromatics hydrocarbons and alkyl aromatic and a permeate rich in multi-ring aromatics. The recovered retentate is similar to a solvent extracted raffinate but possesses a higher concentration of alkyl-single ring aromatics. The membrane separation process is highly selective for removing multi-ring aromatics from the lube distillate.
    Type: Grant
    Filed: December 19, 1989
    Date of Patent: October 9, 1990
    Assignee: Exxon Research and Engineering Company
    Inventors: Laura E. Black, Robert C. Schucker
  • Patent number: 4874523
    Abstract: A method is disclosed for reducing the cloud point of materials comprising the steps of chilling the waxy oil so as to achieve submicron crystallization followed by ultrafiltration thereby effecting separation of a permeate of reduced cloud point from a retentate. Chilling to produce submicron crystallization is to a temperature about 3.degree. C. or less above the cloud point of the material, preferably from 0.5.degree. to 2.degree. C. above the cloud point of the material, most preferably between 1.degree. to 2.degree. C. above the cloud point of the material. In general any mixture, solution or melt containing components which crystallize at different temperatures can be separated by this procedure. The method is especially useful for reducing the cloud point of waxy hydrocarbon oils.
    Type: Grant
    Filed: August 12, 1988
    Date of Patent: October 17, 1989
    Assignee: Exxon Research and Engineering Company
    Inventor: Lucie Y. LaFreniere
  • Patent number: 4872967
    Abstract: Disclosed is a process for catalytically reforming a gasoline boiling range hydrocarbonaceous feedstock wherein the reforming is conducted in two or more stages wherein each stage is separated from another stage by aromatics removal from the reaction stream of a preceding stage. The resulting aromatics-lean stream is passed to a downstream reforming stage.
    Type: Grant
    Filed: May 23, 1988
    Date of Patent: October 10, 1989
    Assignee: Exxon Research and Engineering Company
    Inventors: Kenneth R. Clem, Kenneth J. Heider, James E. Kegerreis, Ehsan I. Shoukry
  • Patent number: 4861628
    Abstract: Thin film membranes of polyurea, polyureapolyurethane alloy, polyurea-polyurea/urethane alloy or polyurea/urethane are prepared by deposition of a thin film of suspension of the selected polymer on a thick permeable support layer by the technique of preparing a suspension of the selected polymer in a solvent which does not dissolve the thick permeable support layer and permitting the solvent to evaporate and/or permeate through the thick-permeable layer.
    Type: Grant
    Filed: October 14, 1987
    Date of Patent: August 29, 1989
    Assignee: Exxon Research and Engineering Company
    Inventor: Robert C. Schucker
  • Patent number: 4797200
    Abstract: This invention relates to a method for upgrading heavy oils for use in subsequent hydrocarbon processing. The process is especially suitable for removing metals which are in the form of nickel or vanadium organic compounds and for lowering the Conradson Carbon Residue of the resulting oil. The process includes the steps of diluting the heavy oil with a solvent which completely solvates the oil and subjecting the resulting mixture to an ultrafiltration step using selected membranes.
    Type: Grant
    Filed: May 4, 1984
    Date of Patent: January 10, 1989
    Assignee: Exxon Research and Engineering Company
    Inventor: Edward J. Osterhuber
  • Patent number: 4772295
    Abstract: A method for recovering hydrocarbon vapor wherein permeable mixed gases of high concentration hydrocarbon vapor and the residual mixed gases of low concentration hydrocarbon vapor are separated, through gas separation membrane, from initial mixed gases containing hydrocarbon vapor to absorb permeable mixed gases, and a method for recovering hydrocarbon vapor wherein initial mixed gases containing hydrocarbon vapor are brought into contact with liquid absorbent to recover hydrocarbon vapor, and gases of high concentration hydrocarbon vapor and gases of low concentration hydrocarbon vapor are separated, through gas separation membrane, from treated gases from which hydrocarbon vapor has been absorbed in the preceeding process.
    Type: Grant
    Filed: May 19, 1987
    Date of Patent: September 20, 1988
    Assignee: Nippon Kokan Kabushiki Kaisha
    Inventors: Moritake Kato, Norio Inoue, Yoshiki Shibuya
  • Patent number: 4758348
    Abstract: A method for separating a charge transfer interactive substance from a liquid mixture containing such a substance, wherein the separation is conducted by means of a separating membrane made of a copolymer having charge transfer interactive groups.
    Type: Grant
    Filed: January 27, 1986
    Date of Patent: July 19, 1988
    Assignee: Sagami Chemical Research Center
    Inventors: Kiyohide Matsui, Kazuhiko Ishihara, Isao Shinohara, Hiroyuki Nishide, Rieko Kogure
  • Patent number: 4748288
    Abstract: The invention is a process for the separation of solvents from hydrocarbons dissolved in the solvents which comprises contacting at elevated pressure a feed solution comprising hydrocarbons dissolved in an aromatic solvent and a polar aliphatic solvent with one side of a dense membrane which is substantially impermeable to the hydrocarbons, and which membrane comprises a layer of a halogen-substituted silicon compound, and recovering the solvents from the other side of the membrane.
    Type: Grant
    Filed: June 23, 1986
    Date of Patent: May 31, 1988
    Assignee: Shell Oil Company
    Inventors: Johan G. A. Bitter, Johannes P. Haan, Hendrik C. Rijkens
  • Patent number: 4571444
    Abstract: In the production of alkylaromatics by the alkylation of aromatic hydrocarbons with alkylating agents such as olefins typically in the presence of a catalyst, the unconverted aromatic hydrocarbon remaining after completion of the alkylation process is separated from the alkylaromatic product and the terminal alkylaromatic isomers are separated from the mixture of alkylaromatic isomers produced in the alkylation process by the selective permeation of the aromatic hydrocarbon and the terminal isomers through a permselective membrane, preferably an asymmetric membrane producing a permeate rich in the terminal isomers and a retentate which is lean (i.e., depleated) in the terminal isomers. Permeation is under reverse osmosis conditions, that is, under a pressure sufficient to at least overcome the osmotic pressure of the aromatic hydrocarbon present in the mixture made up of the aromatic hydrocarbon, the olefin and the mixed isomer alkylaromatic product.
    Type: Grant
    Filed: April 27, 1984
    Date of Patent: February 18, 1986
    Assignee: Exxon Research and Engineering Co.
    Inventors: Laura E. Black, Heather A. Boucher
  • Patent number: 4553983
    Abstract: A process for recovering and concentrating organic vapor from a feed stream of air having an organic vapor content of no more than 20,000 ppm by volume. A thin semipermeable membrane is provided which has a feed side and a permeate side, a selectivity for organic vapor over air of at least 50, as measured by the ratio of organic vapor permeability to nitrogen permeability, and a permeability of organic vapor of at least 3.times.10.sup.-7 cm.sup.3 (STP) cm/cm.sup.2 sec.cm Hg. The feed stream is passed across the feed side of the thin semipermeable membrane while providing a pressure on the permeate side which is lower than the feed side by creating a partial vacuum on the permeate side so that organic vapor passes preferentially through the membrane to form an organic vapor depleted air stream on the feed side and an organic vapor enriched stream on the permeate side. The organic vapor which has passed through the membrane is compressed and condensed to recover the vapor as a liquid.
    Type: Grant
    Filed: July 31, 1984
    Date of Patent: November 19, 1985
    Assignee: Membrane Technology and Research, Inc.
    Inventor: Richard W. Baker
  • Patent number: 4532041
    Abstract: Asymmetric polyimide reverse osmosis membranes of high flux and selectivity for organic liquid separations are described. These membranes are prepared from undegraded polyimide by dissolving from 14-30 wt. % of the undegraded polymer in a dual solvent system comprising a polymer pro-solvent/anti-solvent wherein the pro-solvent is DMF and the anti-solvent is dioxane, wherein the ratio of anti-solvent/pro-solvent ranges from about 10:1 or more-1:1, preferably about 8:1-1.5:1, most preferably about 7:1-3:1; the polymer-solvent mixture is spread into a thin film of the desired thickness and permitted to evaporate for a time just sufficient to permit formation of an asymmetric dense active layer, i.e., within the range 2-120 seconds, preferably 2-60 seconds, most preferably 2-20 seconds before being immersed in a gelation bath.The membranes may be fabricated in the form of sheets, tubes, hollow fibers, etc.
    Type: Grant
    Filed: December 22, 1983
    Date of Patent: July 30, 1985
    Assignee: Exxon Research and Engineering Co.
    Inventors: Harry F. Shuey, Wankei Wan
  • Patent number: 4532029
    Abstract: The present invention is directed to a process for producing high quality aromatic solvents in the middle distillate range containing 95.sup.+ % aromatics by contacting the liquid feed with a perm selective membrane under pressure thereby selectively permeating the aromatic components as the high quality solvents. This separation can be performed by contacting the feed stream in combination with a low boiling light polar aromatics extraction solvent (such as acetonitrile) with the membrane. The middle distillate feed has a molecular weight range of about 120 to 250 g/mole and an aromatic content of 75 to 90 volume percent aromatics and preferably 80 to 90 volume percent aromatics. The membranes which can be employed to effect this separation are selected from the group of regenerated cellulose, cellulose acetate and polyimide membranes, preferably the polyimide membranes.
    Type: Grant
    Filed: April 27, 1984
    Date of Patent: July 30, 1985
    Assignee: Exxon Research and Engineering Co.
    Inventors: Laura E. Black, Peter G. Miasek, Georges Adriaens