Patents by Inventor Karl H. Hoffmann

Karl H. Hoffmann 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: 4735366
    Abstract: An annular gap-type mill for continuously pulverizing in particular hard mineral substances comprises a grinding container (15) which accommodates an axially symmetrical inner body (13) whose outer surface defines with the inner surface of the grinding container (15) a grindimg gap (23). It is essential that the upper and lower region of the inner body (13) are tapered in opposite directions and adjoined to a common equatorial zone (24) of maxi diameter and that the outer surface of at least one of the regions is curved convexly. The grinding container (15) and/or the inner body (13) may be driven rotatingly. The annular gap-type mill is suited for wet and dry grinding and its quantitative and qualitative output is high.
    Type: Grant
    Filed: October 14, 1986
    Date of Patent: April 5, 1988
    Inventor: Karl H. Hoffmann
  • Patent number: 3953367
    Abstract: An improved technique for making a Raney copper catalyst by contacting particulate copper/aluminum alloy particles with an aqueous solution containing dissolved therein both alkali metal hydroxide and at least one saccharide or glycoside.
    Type: Grant
    Filed: June 28, 1974
    Date of Patent: April 27, 1976
    Assignee: Nalco Chemical Company
    Inventors: Karl H. Hoffmann, Donald R. Anderson, Darrell L. Werges
  • Patent number: 3943171
    Abstract: An improved process for making acrylamide from a composition of acrylonitrile and water utilizing an improved Raney copper catalyst. The catalyst is prepared by contacting particulate copper/aluminum alloy particles with an aqueous solution containing aliphatic hydrocarbon compound having at least two carbon atoms per molecule and further having at least two oxygen containing groups per molecule.
    Type: Grant
    Filed: June 28, 1974
    Date of Patent: March 9, 1976
    Assignee: Nalco Chemical Company
    Inventors: Karl H. Hoffmann, Donald R. Anderson
  • Patent number: 3941720
    Abstract: An improved technique for making a Raney copper catalyst by contacting particulate copper/aluminum alloy particles with an aqueous solution containing dissolved therein both alkali metal hydroxide and polyhydroxylated carboxylic acid.
    Type: Grant
    Filed: June 28, 1974
    Date of Patent: March 2, 1976
    Assignee: Nalco Chemical Company
    Inventors: Karl H. Hoffmann, Donald R. Anderson