Patents Represented by Attorney Eugene Striffler
  • Patent number: 4298051
    Abstract: Coated sand cores containing a boronated aluminum phosphate binding agent are used in the production of die castings having undercut regions because of the favorable combination of shakeout properties, resistance to washout, and resistance to surface penetration.
    Type: Grant
    Filed: September 25, 1979
    Date of Patent: November 3, 1981
    Assignee: NL Industries, Inc.
    Inventor: Enno H. Page
  • Patent number: 4288254
    Abstract: A process is disclosed for preparing a slurry of titanium dioxide having a solids content of at least 60%. In the past titanium dioxide pigment slurries have been prepared by mixing titanium dioxide powder, water and additives in a batch mixer, however, this is a lengthy process and generally results in some agglomeration of the particles. The present process comprises the steps of mixing titanium dioxide pigment, at least one dispersant additive and water to a first mixture having a solids content of at least about 60%, pumping the first mixture through a disperser mill to produce a second mixture free from agglomerates.
    Type: Grant
    Filed: May 19, 1980
    Date of Patent: September 8, 1981
    Assignee: NL CHEM Canada Inc.
    Inventor: Yves Gladu
  • Patent number: 4288415
    Abstract: A process is provided for the manufacture of titanium compounds and particularly titanium dioxide wherein excess titaniferous bearing material is reacted with dilute sulfuric acid having a concentration of between about 25% and about 60% by weight at a temperature below about 140.degree. C., and in the presence of a reducing agent which affects the reduction of ferric iron to ferrous iron. Thereafter, the titanium sulfate may be recovered or further processed to provide titanium dioxide hydrate accompanied by recycling the spent acid for reaction with the titaniferous bearing material charged to the process. The titanium hydrate may be calcined to provide titanium dioxide.
    Type: Grant
    Filed: May 30, 1980
    Date of Patent: September 8, 1981
    Assignee: NL Industries, Inc.
    Inventors: Joseph A. Rahm, Donald G. Cole
  • Patent number: 4288416
    Abstract: A process is provided for the manufacture of titanium compounds and particularly titanium dioxide wherein excess titaniferous bearing material is reacted with dilute sulfuric acid having a concentration of between about 25% and about 60% by weight at a temperature below about 140.degree. C. Thereafter, the titanium sulphate may be recovered or processed to provide titanium dioxide hydrate accompanied by recycling the spent acid for reaction with the titaniferous bearing material charged to the process. The titanium hydrate may be calcined to provide titanium dioxide pigment.
    Type: Grant
    Filed: May 30, 1980
    Date of Patent: September 8, 1981
    Assignee: NL Industries, Inc.
    Inventors: Brian R. Davis, Joseph A. Rahm
  • Patent number: 4284506
    Abstract: The present invention is directed to improved separatory devices employing polyurethane forming compositions, such as hollow fiber separatory devices intended to be used in biomedical applications. The separatory device employs at least one separatory membrane, suitable for the intended end use application, which is secured, potted or sealed in a housing using a cured polyurethane composition. The improvement comprises utilizing as the potting agent a polyurethane composition comprising the reaction product of an NCO-terminated prepolymer and a hydroxy terminated lactone derived polyester. The lactone polyester comprises the reaction product of a lactone such as caprolactone, and a polyol such as 1,6-hexane diol. The lactone derived polyester imparts to the polyurethane-forming composition a desirable balance of properties, including low mix viscosity, high reactivity, i.e., low gel and demold times, and acceptable hardness values, when used as a potting agent in biomedical separatory devices.
    Type: Grant
    Filed: December 26, 1979
    Date of Patent: August 18, 1981
    Assignee: NL Industries, Inc.
    Inventors: Marvin T. Tetenbaum, Barton C. Case
  • Patent number: 4275041
    Abstract: A process is provided for the manufacture of a stable titanyl sulfate solution by diluting a reaction mixture containing iron sulfate and titanyl sulfate with a material selected from water, a titanyl sulfate solution, and mixtures thereof. The titanyl sulfate solution may be recovered or processed to provide titanium dioxide hydrate which may be calcined to provide titanium dioxide pigment.
    Type: Grant
    Filed: September 19, 1980
    Date of Patent: June 23, 1981
    Assignee: NL Industries, Inc.
    Inventors: Joseph L. Waldman, Edgar Klein, Achim Kulling, Joseph A. Rahm
  • Patent number: 4275040
    Abstract: Process of extracting titanium values from titaniferous bearing material by circulating a reaction mixture containing titanium values in an agitation column located within a reaction vessel in a direction countercurrent to the flow of the reaction mixture in the annular space located between the agitation column and the inner reaction vessel wall, said circulation being done in a manner to maintain the titaniferous bearing material in a continuous turbulent suspension flow in the agitation column and discharging the reaction mixture from the reaction vessel and recovering the extracted titanium values.
    Type: Grant
    Filed: May 30, 1980
    Date of Patent: June 23, 1981
    Assignee: NL Industries, Inc.
    Inventor: Brian R. Davis
  • Patent number: 4273746
    Abstract: In connection with the recycling of lead-acid batteries, lead-acid battery mud containing lead sulfate is desulfated by adding to the battery mud, which is maintained at a temperature less than 140.degree. F., an aqueous solution containing an ammonium reagent such as ammonium carbonate or ammonium bicarbonate. The ammonium reagent reacts with the lead sulfate to form an aqueous solution of ammonium sulfate and a lead carbonate precipitate. The aqueous solution of ammonium sulfate is then separated from the battery mud containing the lead carbonate precipitate.
    Type: Grant
    Filed: October 10, 1978
    Date of Patent: June 16, 1981
    Assignee: NL Industries, Inc.
    Inventor: Michael A. Kolakowski
  • Patent number: 4269810
    Abstract: In connection with the recycling of lead-acid batteries, battery muds are desulfated by adding an aqueous solution of a treating agent comprising soluble alkali metal salts or alkali metal hydroxides to crushed battery components. The treating agent reacts with sulfuric acid and lead sulfate to form an aqueous solution of alkali metal sulfates and precipitated lead compounds. Following separation of the reacted battery mud and other crushed battery components, separation of the soluble alkali metal sulfates and solids such as PbO, PbO.sub.2, and precipitated lead compounds is effected.
    Type: Grant
    Filed: October 10, 1978
    Date of Patent: May 26, 1981
    Assignee: NL Industries, Inc.
    Inventor: Michael A. Kolakowski
  • Patent number: 4269811
    Abstract: An efficient and inexpensive method for producing lead monoxide from lead sulfate bearing materials such as recycled battery mud is provided comprising:(a) reacting said material with an ammonium carbonate solution to convert lead sulfate to lead carbonate;(b) decomposing the lead carbonate to form impure lead monoxide;(c) reacting the impure lead monoxide with acetic acid to form a lead acetate solution;(d) contacting the lead acetate solution with carbon dioxide to produce insoluble lead carbonate; and(e) decomposing the lead carbonate to form lead monoxide.
    Type: Grant
    Filed: March 3, 1980
    Date of Patent: May 26, 1981
    Assignee: NL Industries, Inc.
    Inventors: Eugene Striffler, Jr., Michael A. Kolakowski
  • Patent number: 4263042
    Abstract: Soda matte slags are rendered resistant to spontaneous combustion through the addition of silica-bearing fluxes which convert sulfides to silicates.
    Type: Grant
    Filed: November 8, 1979
    Date of Patent: April 21, 1981
    Assignee: N. L. Industries, Inc.
    Inventors: Roger L. Altman, M. Vikram Rao