Patents by Inventor Xinghui Meng

Xinghui Meng 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).

  • Recovery of copper from its sulfides and other sources using halogen reagents and oxidants
    Patent number: 5989311
    Abstract: Copper and nickel are extracted from their elemental state, complex sulfides, ores, and other materials such as scrap by leaching them with a solution containing halogen salts: bromine/bromide, or iodide/iodine, oxygen and sodium or potassium nitrate. The invented process is particularly effective for chalcopyrite and pentlandite in an autoclave at a temperature of 100.degree. C.-150.degree. C.
    Type: Grant
    Filed: July 28, 1997
    Date of Patent: November 23, 1999
    Assignee: South Dakota School of Mines and Technology
    Inventors: Kenneth N. Han, Xinghui Meng
  • Recovery of platinum group metals and rhenium from materials using halogen reagents
    Patent number: 5542957
    Abstract: Platinum group metals and rhenium are extracted from their elemental state, complex ores, and other materials such as catalysts by leaching them with a solution containing ammonium halogen salts--iodide and bromide in the presence oxygen and/or sulfuric acid. The invented process is particularly effective for spent catalysts containing precious metals and rhenium in an autoclave at a temperature of 50.degree. C.-300.degree. C.
    Type: Grant
    Filed: January 27, 1995
    Date of Patent: August 6, 1996
    Assignee: South Dakota School of Mines and Technology
    Inventors: Kenneth N. Han, Xinghui Meng
  • Extraction of precious metals from ores and other precious metal containing materials using halogen salts
    Patent number: 5328669
    Abstract: Platinum group metals, gold and silver are extracted from complex ores, automobile scrap, refractory ores and as naturally occurring by leaching the precious metal containing materials with a solution containing halogen salts such as potassium or sodium iodide and bromide in the presence of ammonium ions and oxygen. The precious metal containing materials and reactants are charged into a reaction zone held at high temperatures and pressures to form a slurry containing a precious metal ion solution. The precious metal ion solution is separated from the slurry and subjected to recovering techniques to recover the precious metals.
    Type: Grant
    Filed: January 26, 1993
    Date of Patent: July 12, 1994
    Assignee: South Dakota School of Mines and Technology
    Inventors: Kenneth N. Han, Xinghui Meng
  • Ammonia extraction of gold and silver from ores and other materials
    Patent number: 5308381
    Abstract: Gold and silver are extracted from their elemental state or from complex ores and alloys by leaching them with a solution containing ammonia, ammonium salts and one or more oxidants. The process is particularly effective for refractory gold ores including sulfide and carbonaceous ores.
    Type: Grant
    Filed: April 15, 1993
    Date of Patent: May 3, 1994
    Assignee: South Dakota School of Mines & Techology
    Inventors: Kenneth N. Han, Xinghui Meng
  • Ammonia extraction of gold and silver from ores and other materials
    Patent number: 5114687
    Abstract: Gold and silver are extracted from their elemental state or from complex ores and alloys by leaching them with a solution containing ammonia, ammonium salts and one or more oxidants. The process is particularly effective for refractory gold ores including sulfide and carbonaceous ores.
    Type: Grant
    Filed: December 14, 1990
    Date of Patent: May 19, 1992
    Assignee: South Dakota School of Mines & Technology
    Inventors: Kenneth N. Han, Xinghui Meng