Patents by Inventor Herbert Valdsaar

Herbert Valdsaar 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).

  • Process for removing inorganic gels and incompressible solids from acidic media
    Patent number: 5158688
    Abstract: A process for removing inorganic gels and dispersed, particulate incompressible solids from a highly acid aqueous slurry (e.g., pH of -2 to +3) and a soluble metallic chloride content (e.g., 3 to 50%) involving rapidly and intimately contacting the slurry with a cationic Mannich polyacrylamide of molecular 4-15 million until a desired amount of gel and particulate solids are flocculated. By slowly and gently mixing a floc of the desired size is formed which is then removed. The process is especially suited for treating slurries produced by water quenching the hot metal chlorides and blowover ore and coke from a TiO.sub.2 chlorinator after TiCl.sub.4 has been removed.
    Type: Grant
    Filed: March 19, 1990
    Date of Patent: October 27, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: John S. Craven, Herbert Valdsaar
  • Abrasive particles consisting of crystalline titanium diboride in a metal carbide matrix
    Patent number: 4132534
    Abstract: This invention relates to abrasive particles and process for their preparation. The particles consist essentially of a matrix of titanium carbide, zirconium carbide and tantalum carbide, at least partially in solid solution form and grains of crystalline titanium diboride dispersed throughout the carbide matrix. These abrasive particles are particularly useful as components of grinding wheels for abrading steel.
    Type: Grant
    Filed: September 27, 1977
    Date of Patent: January 2, 1979
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Herbert Valdsaar
  • Transition metal carbide and boride abrasive particles
    Patent number: 4076506
    Abstract: This invention relates to abrasive particles and process for their preparation. The particles consist essentially of a matrix of titanium carbide and zirconium carbide, at least partially in solid solution form and grains of crystalline titanium diboride dispersed throughout the carbide matrix. These abrasive particles are particularly useful as components of grinding wheels for abrading steel.
    Type: Grant
    Filed: September 30, 1976
    Date of Patent: February 28, 1978
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Herbert Valdsaar