Patents by Inventor Hartmut Pietsch

Hartmut Pietsch has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4775107
    Abstract: A mechanical disintegration is effected in which substantially only the metal sheath of the small batteries is torn apart. The crushed material is roasted at 500.degree. to 1000.degree. C. in a state of motion in an oxidizing atmosphere and the volatilized mercury is recovered from the exhaust gas. The roasted material is separated by sieving and magnetic separation into an iron-containing scrap fraction, a brass-containing scrap fraction and a collectable fraction, which contains manganese, zinc and silver.
    Type: Grant
    Filed: April 21, 1987
    Date of Patent: October 4, 1988
    Assignee: Metallgesellschaft AG
    Inventors: Rudolf Heng, Walter Koch, Hartmut Pietsch
  • Patent number: 4472359
    Abstract: A process of leaching ores, ore concentrates, intermediate metallurgical products and the like, which contain acid-soluble constituents, by a treatment in an acid aqueous solution under pressure in a tubular reactor. The slurry contains suitably 300 to 1100 g starting material per liter of water and a velocity of flow of 0.5 to 4.0 m/sec. is suitably maintained throughout the flow path in the tubular reactor of the slurry and of the leached suspension.
    Type: Grant
    Filed: February 23, 1982
    Date of Patent: September 18, 1984
    Assignees: Metallgesellschaft AG, Vereinigte Aluminium-Werke AG
    Inventors: Hartmut Pietsch, Wolfgang Turke, Hubert Bings, Karl-Josef Memmel
  • Patent number: 4438076
    Abstract: Gold and/or silver is leached from comminuted ore with an alkaline cyanide lixiviant at a superatmospheric pressure of at least 25 bar and with high purity oxygen (at least 90% pure) to reduce the residence time at high yield.
    Type: Grant
    Filed: August 12, 1983
    Date of Patent: March 20, 1984
    Assignees: Metallgesellschaft AG, Vereinigte Aluminum-Werke AG
    Inventors: Hartmut Pietsch, Wolfgang Turke, Ernst Bareuther, Fritz Kampf, Hubert Bings
  • Patent number: 4436704
    Abstract: A method of recovering uranium dioxide from a sodium uranyl carbonate solution obtained by the alkaline carbonate leaching of uranium ore in which a solution is reacted at a temperature above 130.degree. C. and at superatmospheric pressure with particular metallic iron. The precipitated UO.sub.2 is recovered from the solution.
    Type: Grant
    Filed: June 24, 1982
    Date of Patent: March 13, 1984
    Assignee: Metallgesellschaft Aktiengesellschaft
    Inventors: Otmar Krennrich, Gottfried Brendel, Hartmut Pietsch
  • Patent number: 4361541
    Abstract: A method for continuously extracting uranium from ores comprises the steps of forming a slurry of ore in a leaching solution; heating the slurry while pumping it through a tube reactor at high turbulences characterized by Reynolds numbers in excess of 50,000; supplying gaseous oxygen at high pressures of at least 30 bar into the tube reactor such that the uranium is substantially completely oxidized in a soluble form but impurities in the slurry are substantially kept from becoming soluble; recovering the uranium oxide solute which is substantially free of impurities.
    Type: Grant
    Filed: September 4, 1979
    Date of Patent: November 30, 1982
    Assignees: Vereinigte Aluminium-Werke Aktiengesellschaft, Metallgesellschaft Aktiengesellschaft
    Inventors: Hubert Bings, Fritz Kampf, Roland Thome, Gerhard Wargalla, Gunter Winkhaus, Hartmut Pietsch, Wolfgang Turke, Peter Fischer
  • Patent number: 4322271
    Abstract: N-Vinyl-N-alkyl-carboxylic acid amides are prepared, starting from N-ethyl-carboxylic acid amides, in a 3-stage process consisting of the following stages:(a) anodic alkoxylation of the N-ethyl-carboxylic acid amides to give N-.alpha.-alkoxyethyl-carboxylic acid amides;(b) alkylation of these N-.alpha.-alkoxyethyl-carboxylic acid amides with an alkyl halide or dialkyl sulfate in an alkaline medium to give N-.alpha.-alkoxyethyl-N-alkyl-carboxylic acid amides; and(c) splitting off of alcohol from the products of stage (b) by heating to temperatures between about 60.degree. and about 350.degree. C.Instead of stages (b) and (c), it is also possible to carry out the following stages after stage (a):(b.sub.1) splitting off of alcohol from the N-.alpha.-alkoxyethylcarboxylic acid amides obtained in stage (a) by heating to temperatures of about 60.degree. to about 600.degree. C., to give N-vinyl-carboxylic acid amides; and(c.sub.
    Type: Grant
    Filed: May 14, 1980
    Date of Patent: March 30, 1982
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Harald Jensen, Erwin Schmidt, Michael Mitzlaff, Jurgen Cramer, Rudolf Pistorius, Hartmut Pietsch, Klaus Dehmer
  • Patent number: 4052453
    Abstract: Process for preparing acetoacetamide-N-sulfofluoride by reacting amidosulfofluoride at a temperature of from 50.degree. to 100.degree. C with diketene, optionally in the presence of inert solvents or diluents.
    Type: Grant
    Filed: October 1, 1975
    Date of Patent: October 4, 1977
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Hartmut Pietsch, Karl Clauss, Harald Jensen, Erwin Schmidt
  • Patent number: 4009161
    Abstract: 3-Sulfohalides of 6-methyl-2H-1,3-oxazin-2,4(3H)-dione of the formula I ##STR1## in which X represents fluorine or chlorine are prepared by reacting fluorosulfonyl isocyanate or chlorosulfonyl isocyanate, at a temperature of from -35.degree. to +70.degree. C, optionally in the presence of an inert solvent, with diketene, acetoacetyl fluoride, acetoacetyl chloride, acetoacetic acid or an isopropenyl ester of the formula CH.sub.2 =C(OOCR)-CH.sub.3 in which R represents an alkyl radical having from 1 to 4 carbon atoms, a substituted or unsubstituted phenyl or benzyl radical.
    Type: Grant
    Filed: July 16, 1975
    Date of Patent: February 22, 1977
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Hartmut Pietsch, Karl Clauss, Erwin Schmidt, Harald Jensen
  • Patent number: 3993689
    Abstract: Compounds of the formula ##SPC1##In which R represents an alkyl radical having from 1 to 4 carbon atoms and Hal stands for fluorine or chlorine are prepared by reacting at a temperature of from -40.degree. to +20.degree. C an i-propenylalkanoic acid ester of the formula ##EQU1## with an isocyanate of the formulaO=C=N--SO.sub.2 Hal (V)in which R and Hal have the same meaning as above, and isolating the compound of formula III.
    Type: Grant
    Filed: July 16, 1975
    Date of Patent: November 23, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Erwin Schmidt, Karl Clauss, Hartmut Pietsch, Harald Jensen
  • Patent number: 3969348
    Abstract: 6-Methyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide or the nontoxic salts thereof is prepared by reacting 6-methyl-2,3-dihydro-1,3-oxazin-2,4-dione-3-sulfo-fluoride of the formula ##EQU1## with at least 1 mole water per mole of fluoride to obtain acetoacetamide-N-sulfo-fluoride with splitting off of CO.sub.2, treating the acetoacetamide-N-sulfofluoride with an aqueous and/or alcoholic base and isolating the oxathiazinone or the salts thereof.
    Type: Grant
    Filed: July 16, 1975
    Date of Patent: July 13, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Hartmut Pietsch, Karl Clauss, Erwin Schmidt, Harald Jensen
  • Patent number: 3969347
    Abstract: The potassium salt practically free of fluoride of 6-methyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide is prepared by cyclization of acetoacetamide-N-sulfofluoride with at least two moles potassium hydroxide, potassium methylate or a mixture of potassium hydroxide and potassium methylate per mole of sulfofluoride in methanol as solvent containing less than 50 % by weight of water at a temperature of from -20.degree. to +60.degree.C and separating the crystalline potassium salt of the oxathiazinone dioxide from the reaction solution. The compound obtained has a pure sweet taste.
    Type: Grant
    Filed: July 16, 1975
    Date of Patent: July 13, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Erwin Schmidt, Karl Clauss, Hartmut Pietsch, Harald Jensen
  • Patent number: 3968107
    Abstract: 6-Methyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide and the nontoxic salts thereof are prepared by reacting acetoacetic acid with fluorosulfonyl isocyanate at a temperature of from -20.degree.C to +50.degree.C in the presence of from 0.5 to 2 moles, calculated on the FSI used, of an alkali methal fluoride or a tertiary amine of the formulaN(R.sub.1)(R.sub.2)(R.sub.3)in which R.sub.1, R.sub.2, R.sub.3 represent identical or different alkyl radicals having from 1 to 10 carbon atoms, two of the radicals R.sub.1 to R.sub.3 optionally form together an alkylene radical having from 4 to 5 carbon atoms which may contain N, O, or S as hetero atom, or one of the radicals R.sub.1 to R.sub.3 represents a phenyl radical, or of pyridine or quinoline, or of a mixture of the aforesaid compounds, and transforming the salt of acetoacetamide-N-sulfofluoride obtained into the oxathiazinone salt or the free oxathiazinone by a treatment with aqueous and/or alcoholic bases.
    Type: Grant
    Filed: July 16, 1975
    Date of Patent: July 6, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Karl Clauss, Erwin Schmidt, Hartmut Pietsch, Harald Jensen
  • Patent number: 3968106
    Abstract: 6-Methyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide and the nontoxic salts thereof are prepared by reacting acetone and fluorosulfonyl isocyanate in a molar proportion of from 14:1 to 150:1 at a temperature of from 0.degree. to 60.degree.C, distilling off the excess acetone from the reaction mixture with acetoacetamide-N-sulfofluoride and bringing about cyclization by a treatment with bases at a pH of from 5 to 12. The oxathiazinone derivatives are used as sweeteners.
    Type: Grant
    Filed: July 16, 1975
    Date of Patent: July 6, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Karl Clauss, Hartmut Pietsch, Erwin Schmidt, Harald Jensen