Abstract: A system and process for recovering copper from a copper-containing ore, concentrate, or other copper-bearing material to produce high quality cathode copper from a leach solution without the use of copper solvent extraction techniques or apparatus. A process for recovering copper from a copper-containing ore generally includes the steps of providing a feed stream containing comminuted copper-containing ore, concentrate, or other copper-bearing material, leaching the feed stream to yield a copper-containing solution, conditioning the copper-containing solution through one or more physical or chemical conditioning steps, and electrowinning copper directly from the copper-containing solution, without subjecting the copper-containing solution to solvent extraction.

Abstract: The present invention relates generally to a process for the production of sulfuric acid and liberation of precious metal values from materials containing sulfur through pressure leaching operations. In accordance with various aspects of the present invention, the sulfur-bearing materials may comprise residues from pressure leaching operations, such as those carried out at medium temperatures. The process of the present invention can be advantageously used to convert such sulfur-bearing materials to sulfuric acid by means of pressure leaching. The sulfuric acid so produced can be used beneficially in other mineral processing operations, for example those at the site where it is produced. Metals, such as precious metals, that are contained within the sulfur-bearing materials advantageously may be recovered from processing products by established precious metals recovery technology.

Abstract: The present invention is directed to a process for recovering metal values from metal-bearing materials. During a reactive process, a seeding agent is introduced to provide a nucleation site for the crystallization and/or growth of solid species which otherwise tend to passivate the reactive process or otherwise encapsulate the metal value, thereby reducing the amount of desired metal values partially or completely encapsulated by such material. The seeding agent may be generated in a number of ways, including the recycling of residue or the introduction of foreign substances. Processes embodying aspects of the present invention may be beneficial for recovering a variety of metals such as copper, gold, silver, nickel, cobalt, molybdenum, zinc, rhenium, uranium, rare earth metals, and platinum group metals from any metal-bearing material, such as ores and concentrates.

Abstract: A system and process for recovering copper from a copper-containing ore, concentrate, or other copper-bearing material to produce high quality cathode copper from a leach solution without the use of copper solvent extraction techniques or apparatus. A process for recovering copper from a copper-containing ore generally includes the steps of providing a feed stream containing communicated copper-containing ore, concentrate, or other copper-bearing material, leaching the feed stream to yield a copper-containing solution, conditioning the copper-containing solution through one or more physical or chemical conditional steps, and electowinning copper directly from the copper-containing solution, without subjecting the copper-containing solution to solvent extraction.

Abstract: The present invention relates generally to a process for recovering copper and other metal values from metal-containing materials using controlled, super-fine grinding and medium temperature pressure leaching. Processes embodying aspects of the present invention may be beneficial for recovering a variety of metals such as copper, gold, silver, nickel, cobalt, molybdenum, rhenium, zinc, uranium, and platinum group metals, from metal-bearing materials, and find particular utility in connection with the extraction of copper from copper sulfide ores and concentrates.

Abstract: The present invention relates generally to a process for recovering copper and other metal values from metal-containing materials through pressure leaching operations. In accordance with the various aspects of the present invention, metal-containing pregnant leach solutions from pressure leaching operations need not be significantly diluted to facilitate effective metal recovery using solvent extraction and electrowinning.

Abstract: The present invention relates generally to a process for the production of sulfuric acid and liberation of precious metal values from materials containing sulfur through pressure leaching operations. In accordance with various aspects of the present invention, the sulfur-bearing materials may comprise residues from pressure leaching operations, such as those carried out at medium temperatures. The process of the present invention can be advantageously used to convert such sulfur-bearing materials to sulfuric acid by means of pressure leaching. The sulfuric acid so produced can be used beneficially in other mineral processing operations, for example those at the site where it is produced. Metals, such as precious metals, that are contained within the sulfur-bearing materials advantageously may be recovered from processing products by established precious metals recovery technology.

Abstract: A method for converting a retrograde substance from a liquid to a gaseous state comprising bringing the substance to a defined initial state of pressure and volume, and relaxing to a defined final state. The defined states correspond to regions on the pressure-volume diagram of the substance, the initial state lying to the lower volume side of a boundary defined by the branch of the critical isentrope lying to the greater pressure side of the critical point, and by the stability limit of the substance. The final state lies to the greater volume side of this boundary.

Abstract: Sylvinite ores are treated for removal of insoluble slimes by a froth flotation technique which includes flocculating the slimes with nonionic or polyacrylamide flocculants and thereafter utilizing a nonionic or an anionic flotation collector including a mixture of fuel oil or a fatty acid and a defoamer of the glycol ester or polyglycol ester type. The flocculated slimes may also be floated with a fatty acid collector alone at low pH conditions.