Patents Examined by Frank Spear
  • Patent number: 5554286
    Abstract: A membrane for liquid mixture separation is composed of an A-type zeolite film deposited on a porous support after seed crystals are held on a surface of the support.
    Type: Grant
    Filed: June 22, 1995
    Date of Patent: September 10, 1996
    Assignee: Mitsui Engineering & Shipbuilding Co., Ltd.
    Inventors: Kenichi Okamoto, Hidetoshi Kita, Masakazu Kondo, Norikazu Miyake, Yasuo Matsuo
  • Patent number: 5554292
    Abstract: A separatory membrane is provided which has sufficient durability and shows a high rate of permeation therethrough, a high separation factor to a variety of organic substances having a wide range of concentration thereof in mutual separation of organic substances and separation of a water/organic substance mixture by pervaporation, vapor permeation or perstraction. The separatory membrane shows that water permeates selectively through the membrane while satisfying such conditions that the product (QL) of the rate Q (kg/m.sup.2.hr) of permeation and the thickness L (.mu.m) of the membrane is at least 0.5 kg..mu.m/m.sup.2.hr, and that the separation factor .alpha..gtoreq.10 and log.alpha..gtoreq.-1.77.times.log(QL)+2.77 when the pervaporation performance of a 5-30 .mu.m-thick dense uniform membrane is evaluated using, as a liquid feed, an 80 wt. % aqueous solution of acetic acid at a temperature of 70.degree. C.
    Type: Grant
    Filed: April 5, 1993
    Date of Patent: September 10, 1996
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Yasushi Maeda, Kengo Magara, Hitoshi Tsugaya
  • Patent number: 5552054
    Abstract: The invention relates to a composite membrane with a porous polymer support layer and a polymer top layer, whereby the porous polymer support layer is of polyacrylonitrile (PAN), polyacrylamide, polyetheretherketone (PEEK), polyetherketone (PEK), polysulfon or polyethersulfon, whereas the polymer top layer is a dense layer comprising polyvinyl chloride with selective water permeability. Preferably the membrane is provided with a porous polyacrilonitril support layer and a polyvinyl chloride top layer. Further the invention comprises the application of such a composite membrane for the dehydration of organic solvents using such a composite membrane.
    Type: Grant
    Filed: March 22, 1995
    Date of Patent: September 3, 1996
    Assignee: Deutsche Carbone AG Membran-Trennverfahren GFT
    Inventors: Geert-Hendrik Koops, Marcellinus H. V. Mulder, Cornelis A. Smolders
  • Patent number: 5552049
    Abstract: A ceramic fiber reinforced filter is prepared by depositing a thin filtration layer of preselected pore size on a more porous ceramic support. The filter is characterized by a low pressure drop across the filtration layer in operation and easy back pressure pulse cleaning.
    Type: Grant
    Filed: January 19, 1995
    Date of Patent: September 3, 1996
    Assignee: Du Pont Lanxide Composites, L.P.
    Inventor: Paul E. Gray
  • Patent number: 5552053
    Abstract: The present invention is directed to a solid poly-amphiphilic polymer. The polymer may be (1) a continuous film (a) which is strengthened sufficiently by cross-linking to be used alone and/or supported on a frame, (b) overlaid and/or cast on a porous hydrophobic support or (2) introduced into the pores of a microporous hydrophobic membrane. The present invention is also a process for selectively removing a dissolved species (solute or target compound) from an aqueous solution or from a gaseous stream comprising contacting said aqueous solution or gaseous stream having the dissolved species and an aqueous stripping solution or other means for removing said species with opposite sides or surfaces.
    Type: Grant
    Filed: November 15, 1994
    Date of Patent: September 3, 1996
    Assignee: Monsanto Company
    Inventors: Sa V. Ho, Robert Z. Greenley, Alan S. Michaels
  • Patent number: 5549830
    Abstract: A method of processing a feed liquid in the form of an extraction solution containing taxane solutes that is an extraction product of a biomass utilizes at least one semipermeable membrane to remove at least one taxane solute from the solvent by reverse osmosis. The feed liquid is placed in a first region on one side of the membrane and pressure is supplied to transport constitutes of the feed liquid across the membrane to a second region as a first permeate while retaining a first retentate in the first region. The taxane solute may be either retained or transported. Where the taxane solute is transported, the method can further include the use of a second semipermeable membrane of a pore size different from the first membrane and supplying a pressure to transport some of the first permeate across the second membrane as a second permeate while retaining a majority of the desired taxane solute as a second retentate.
    Type: Grant
    Filed: February 28, 1994
    Date of Patent: August 27, 1996
    Assignee: NaPro BioTherapeutics, Inc.
    Inventors: David R. Carver, Timothy R. Prout, Christopher T. Workman, Charles L. Hughes
  • Patent number: 5549829
    Abstract: An apparatus for producing a high solids content aqueous dispersion from a low solids content aqueous dispersion, for example waste water containing dilute emulsion paint. At least two membranes are arranged in series, a first membrane being of hollow fibre structure with a bore diameter greater than 1 mm and a pore size of less than 3,000 Kilodaltons molecular weight cut off, and a second tubular membrane being of bore diameter less than 50 mm and pore size of less than 3,000 Kilodaltons molecular weight cut off. The low solids content dispersion is passed across a face of the first membrane at a cross flow velocity of from 0.5 to 5.0 meters per second, a differential pressure being applied to force liquid through the membrane. The resultant retentate has an intermediate solids content and is passed across a face of the tubular membrane at a cross flow velocity of from 0.5 to 5.0 meters per second. A differential pressure is applied across the tubular membrane to force liquid therethrough.
    Type: Grant
    Filed: May 22, 1995
    Date of Patent: August 27, 1996
    Assignee: Northwest Water Group PLC
    Inventor: Minh Son Le
  • Patent number: 5547575
    Abstract: Fabrication of the surface-grafted microporous membranes by coating the membrane with an N-halogenated compound, followed by grafting with an unsaturated monomer and sodium dithionite in a primarily aqueous solution that may contain an organic halogen compound selected from carbon tetrachloride and trichloroacetic acid. The coating may be formed in situ and may be cross-linked.
    Type: Grant
    Filed: December 23, 1994
    Date of Patent: August 20, 1996
    Assignee: Sartorius AG
    Inventors: Wolfgang Demmer, Hans-Heinrich Horl, Dietmar Nussbaumer, Abdul R. Weiss, Eberhard Wunn
  • Patent number: 5545329
    Abstract: A method for refining oil, in particular domestic edible oils and petroleum crude oils, by membrane separation technology. The invention involves treating such oils in a membrane module system that provides optimal separation performance and service life. The described process simplifies oil processing and permits the attainment of the desired product in an essentially single step operation.
    Type: Grant
    Filed: May 8, 1995
    Date of Patent: August 13, 1996
    Assignee: Rochem Separation Systems
    Inventor: David A. LaMonica
  • Patent number: 5543055
    Abstract: A process for the purification of bis(difluoromethyl)ether. Bis(difluoromethyl)ether is exposed to molecular sieves in order to reduce or completely remove impurities. In a further embodiment, the present invention optionally includes means for preferentially inhibiting the formation of CF.sub.2 HOCCl.sub.3 in the formation of bis(difluoromethyl)ether prior to exposing the bis(difluoromethyl)ether to the molecular sieves.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: August 6, 1996
    Assignee: Hampshire Chemical Corp.
    Inventors: Gerald J. O'Neill, Robert J. Bulka
  • Patent number: 5543045
    Abstract: A charge mosaic membrane is made of a cationic polymer and an anionic polymer. At least one of the cationic and anionic polymers is in the form of spheres having a diameter of 0.01-10 .mu.m. A process for the production of the charge mosaic membrane is also described.
    Type: Grant
    Filed: March 7, 1994
    Date of Patent: August 6, 1996
    Assignee: Dainichiseika Color & Chemicals Mfg. Co., Ltd.
    Inventors: Takashi Fukutomi, Minoru Takizawa, Michiei Nakamura
  • Patent number: 5543046
    Abstract: The inorganic membrane consists of a macroporous inorganic support and an inorganic membrane layer. The membrane layer is formed through depositing an inorganic layer by "Chemical Vapour Deposition" or "sputtering" on the macroporous support, onto this inorganic layer a photo-lacquer layer is formed, this photo-lacquer layer being exposed to a regular mask pattern with the use of a suitable source, this lacquer layer being developed, and in the inorganic layer the mask pattern is etched by a suitable etchant, thus forming the membrane layer. The pattern of the membrane layer may be given any particular design, practically with a repetition rate in the range 0.1-10 .mu.m. It is thus conceivable to separate not only particles according to their size, but also to their shape. The membrane layer can be deposited very thinly in comparison to the dimension of the pore size, enabling a large flux, a reduced clogging and a minimal damage to particles or cells.
    Type: Grant
    Filed: January 17, 1995
    Date of Patent: August 6, 1996
    Inventor: Cornelis J. M. Van Rijn
  • Patent number: 5538642
    Abstract: Spiral wound membrane elements have permeate flow channels attached to a porous polymeric mandrel in a regular and closely spaced array. The permeate flow channels are attached to the mandrel by means of ultrasonic welding. The attaching means permits the attachment of a high density of permeate flow channels.
    Type: Grant
    Filed: October 19, 1994
    Date of Patent: July 23, 1996
    Assignee: The Dow Chemical Company
    Inventor: Gregory D. Solie
  • Patent number: 5538638
    Abstract: A method and apparatus for testing a pharmacological IV admixture for contaminants, following filtering of turbid liquids such as emulsions through a micropore filter, includes the step of first air purging or gas purging residual emulsion particles through the micropore filter using pressure, before admitting a growth medium to the upstream side of the filter. The air purging of these emulsion particles, so that they are substantially removed from the upstream side of the filter, enables the successful sterility testing of the filter by admitting clear growth medium, waiting the required culturing time and observing for turbidity which evidences growth of microbes. The described procedure removes residual emulsion particles simply and effectively so that the visual test is effective. In a preferred embodiment the procedure is carried out using a sealed, sterile growth medium bag connected to the filter assembly, the bag having a quantity of sterile air along with the liquid growth medium.
    Type: Grant
    Filed: June 27, 1994
    Date of Patent: July 23, 1996
    Inventor: Hilary R. Hedman
  • Patent number: 5538643
    Abstract: Apparatus for interfacing a liquid chromatograph (LC) with a spectrometer such as a Fourier transform infrared spectrometer, the LC having an eluant, the eluant containing a solvent and a component of interest. The apparatus includes five basic parts. The first is a means for generating a stream of droplets of the eluant, such as a nebulizer. The second is a means for removing most of the solvent from the stream of droplets of the eluant to thereby generate a stream of particles, the particles containing the component of interest and any residual solvent, such as a membrane solvent separator/momentum separator combination. The third is a cryogenic receiving surface, such as a gold drum.
    Type: Grant
    Filed: May 2, 1995
    Date of Patent: July 23, 1996
    Assignee: The Dow Chemical Company
    Inventors: George J. Kallos, Richard R. Papenfuss
  • Patent number: 5538640
    Abstract: A pervaporation apparatus and process adapted to handle a diverse range of feed stream compositions and volumes. The apparatus includes a pervaporation unit and condenser, one or more tanks and a control system to direct liquid flows within the apparatus according to the chosen processing scheme. The apparatus and process can achieve separation performance comparable to a one-stage, two-stage, two-step or more complicated pervaporation system, including those in which two-phase permeates are produced.
    Type: Grant
    Filed: July 25, 1994
    Date of Patent: July 23, 1996
    Assignee: Membrane Technology and Research, Inc.
    Inventors: Johannes G. Wijmans, Juergen Kaschemekat, Richard W. Baker
  • Patent number: 5534150
    Abstract: A selectively-permeable membrane constituted by a composition comprising starch and a synthetic thermoplastic polymer is used for separating liquid aqueous-organic mixtures by pervaporation.
    Type: Grant
    Filed: May 17, 1994
    Date of Patent: July 9, 1996
    Assignee: Novamont S.P.A.
    Inventors: Catia Bastioli, Vittorio Bellotti
  • Patent number: 5531899
    Abstract: A composite ultrahigh molecular weight polyethylene microporous membrane is provided having cation exchange capacity. The membrane is useful for removing metal ions from acidic aqueous solutions.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: July 2, 1996
    Assignee: Millipore Investment Holdings Limited
    Inventors: Larry Y. Yen, Ven Anantharaman, Bipin Parekh
  • Patent number: 5531893
    Abstract: Hydrophilic inter-penetrating network charge modified microporous membranes are provided as well as a method of preparing the membranes by casting a membrane matrix blend containing matrix polymer, a solvent system, a wetting polymer compatible with the matrix polymer, and a charge modified system which forms a cross-linked interpenetrating network structure within the microporous membrane substrate during the membrane fabrication process which network structure optionally can be locked in by heat curing. The membranes are useful for filtering ultrapure water with 18 megaohm-cm resistivity for the electronic industry, and they can also be used for the removal of a variety of contaminants from fluid media, such as very fine negatively charged particles, bacteria and endotoxins, with greatly enhanced filtration efficiency.
    Type: Grant
    Filed: December 1, 1993
    Date of Patent: July 2, 1996
    Assignee: Gelman Sciences Inc.
    Inventors: Hopin Hu, Chung-Jen Hou
  • Patent number: RE35292
    Abstract: Organometallic compounds and/or metal carbonyls are separated from their solutions in organic media with the aid of semi-permeable membranes made of aromatic polyamides.
    Type: Grant
    Filed: January 5, 1994
    Date of Patent: July 9, 1996
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Helmut Bahrmann, Michael Haubs, Willi Kreuder, Thomas Muller