South Dakota School of Mines and Technology

Xinghui Meng

Kenneth N Han

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.

Recovery of copper from its sulfides and other sources using halogen

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.

Recovery of platinum group metals and rhenium from materials using

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.

Extraction of precious metals from ores and other precious metal

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.

Growing community of inventors

Rapid City, SD, United States of America

Xinghui Meng