CROSS REFERENCE TO RELATED APPLICATION

This application is a national stage entry of PCT/cl2018/000028 filed Sep. 5, 2018, under the International Convention and claiming priority over Chilean Patent Application No. CL1777-2017 filed Jul. 5, 2017.

TECHNICAL FIELD

The present application is a method for the simultaneous extraction of multiple chemical elements (base metals, precious, rare earths, semimetals, etc.) contained in various materials (minerals, industrial wastes, meteorites, etc.).

STATE OF THE ART

As one of the most robust industries, in size and economy, the mining industry is taken as the basis of analysis to support and justify the invention of the METHOD OF EXTRACTION OF CHEMICAL ELEMENTS FROM MATERIALS BY PRE-TREATMENT CONDUCTING THE SOLUBILIZATION OF ITS REFRACTORY SPECIES, from now on “The Method”.

In the mining industry, there are two different types of metal extraction processes: leaching process and concentration process.

The process of heap leaching for the extraction of metals from minerals, consists of unit operations of size reduction, agglomeration, leaching in fixed or agitated bed, purification and precipitation of a chemical element. This type of leaching is designed to extract a single metal, i.e. copper, and has advantages such as low amount of investment needed and low operation costs; and disadvantages like low extraction performance and long processing cycle.

Bacterial and pressure leaching technologies exist but are evaluated by a trade-off between cost and performance, so the choice of technology lies in the commercial value of the metal extracted.

The main criterion in the pre-selection of the leaching process (in all its variants) is the property of dissolution in acidic medium of the species that contain the metal and for that reason it is applied almost exclusively to minerals of metallic oxides. The process consists of leaching cycles of weeks or months, medium or high acid consumption and mean recoveries metal (70-80%) and generates a solid residue called SPENT ORE.

The other process is the froth flotation—fusion—metal refining process. It is a process consisting of multiple unit operations such as size reduction (crushing and grinding), froth flotation, solid-liquid separation, drying, melting—conversion of the concentrate and metal refining. It is a process which requires high investment and has high operating cost. Its disadvantages lie on several fronts: high energy consumption (mainly grinding and smelting), very high fresh water requirement (grinding and flotation), high pollution potential (polluting gases since fusion—conversion). Its main advantage is the speed of production and efficiency to obtain concentrates. This process is used primarily to extract metals from sulphide ores, very few soluble in acid, so they cannot be treated by the leaching process.

Flotation engineering is somewhat recharged. Each unit operation consists of a large number of equipment: several SAG—ball mills, hundreds of large flotation cells, nest of 8 to 10 hydro cyclones as a grinding control stage, 1-2 settlers, 1-2 clarifiers. All this takes place only at the stage of obtaining the concentrate, which is only the achievement of a mass of mineralogical species (and not of the metal) and generates a large amount of waste, called TAILINGS. This concentration process is complemented by melting—conversion stages, where large-scale furnaces, high energy consumption with great potential for gaseous contamination are used, generating the liquid metal at high temperature (for subsequent refining) and produces a type of waste called SLAG.

Currently, 85% of metal production is developed through the flotation process and the remaining 15% is processed by leaching. This trade-off between the leaching and flotation processes has caused the challenge of processing the sulphide minerals through a leaching process in a commercial manner. A clear example is that the important copper mining industry has proposed to demonstrate technically and commercially the dissolution by leaching of its main and most abundant natural source: chalcopyrite.

Many global studies at the level of research centers, universities and mining companies have focused on this challenge, unfortunately without a positive result accepted by the industry. Universities such as British Columbia (Canada), Cape Town (South Africa), Queensland (Australia), TUDeIft (The Netherlands) and research centers such as CSIRO, BRGM (France), JKTEch (Australia), Max Planck Institute (Germany) among others, have made significant efforts in the study of chemical/bacterial leaching of chalcopyrite. The following references by Dr. Helen Watling of the Australian CSIRO is an excellent result of the studies developed to date in that direction.

Chalcopyrite hydrometallurgy at atmospheric pressure: 1. Review of acidic sulfate, sulfate—chloride and sulfate-nitrate process options. Hydrometallurgy 140: 163-180, November 2013

Chalcopyrite hydrometallurgy at atmospheric pressure: 2. Review of acidic chloride process options. Hydrometallurgy 146: May 2014.

Review of Biohydrometallurgical Metal extraction from Polymetallic Mineral Resources. Minerals 5 (1): 1-60. December 2014.

Several important conclusions can be obtained from the state of the art, to date:

1. The leaching of sulfur minerals of copper, zinc, lead, nickel, molybdenum, silver or other metals has not been commercially demonstrated.

2. All scientific and technological efforts have focused on optimizing each of the unit operations of concentration—fusion—conversion. The concrete thing is that the optimization focused on increasing the dimensions of the equipment, the search to spend less energy and increasing the control of gaseous emissions.

3. The residues of the leaching and flotation-fusion-conversion processes (SPENT ORE, TAILINGS and SLAG) contain small to medium quantities of the metal due to the inefficiency level of both mentioned extraction processes. These wastes are considered environmental liabilities, mainly based on the hypothesis that it is no longer possible to extract more metal and therefore the problem is about how to dispose of the waste in the environment and its passivation control over time.

4. The industry has generated immense historical amounts of SPENT ORE, TAILINGS and SLAG that are have been disposed of in nature and that are recognized as a great environmental problem.

5. The most important conclusion is that sulphide minerals have proven not to be commercially leachable, for that modern leaching history is necessary to know the road of its modern commercial development. You can begin with TL (thin layer) heap leaching which was a technological development led by the Sociedad Minera Pudahuel, a pioneer in Chile. While it originated in a patented concept in the U.S. in the second half of the seventies, it was perfected by this company from its original definition in the laboratory field until it was taken to an industrial application in 1980. These improvements also gave rise to a patent of its own, registered first in Chile (Intellectual Property Registry No. 32.025 “Leaching procedure in heap to layers of mixed copper ore of oxide and sulphide state”) and then in some other countries. In addition, the Sociedad Minera Pudahuel developed bacterial leaching technology in heap for thin layers or BTL through systematic research aimed at knowing the mechanisms of leaching assisted by bacteria.

The results basically consisted of management models for the optimization of the sulfur ore at the leaching processes, thus considerably expanding the spectrum of minerals capable of being economically leached.

For its part, the Compañía Minera Mantos Blancos for its part in 1971, in its Intellectual Property Registry No. 25,930, exhibited its “Improvements in the leaching of mixed minerals of copper oxides and sulphides and other metals using chlorine and compounds oxidized from it, at room temperature and 50° C.”.

Deleew Schmitz Partnerschip in 1979, in his Intellectual Property Registry No. 30,914, reported on his “Procedure for the recovery of copper and silver from sulfur concentrates by leaching with oxygen and ferrous chloride”.

In 1981, DU PONT DE NEMOURS AND COMPANY, in its Intellectual Property Registry No. 32,426, noted its “Procedure for recovering copper from sulphide mineral concentrates by leaching with nitric acid and sulfuric acid to produce a solution containing copper and iron ions supplemented with copper electrodeposition after reducing ferric ions and nitrate and other impurities to obtain high purity copper.”

Degussa Aktiengesellschafe, in the Intellectual Property Registry No. 38,554 of 1993, coined its “Process to leach concentrated minerals or gold and silver wastes by leaching with cyanide supported by hydrogen peroxide and manganese compounds as catalysts for the decomposition of said peroxide”

And finally, for the purposes of this text, Minnesota Mining and Manufacturing Company, in its Registry of Intellectual Property NO 39,510 of the year 1998, specified its “Method of recovering gold and silver by leaching with an aqueous solution containing certain fluoroaliphatic surfactants and polymeric.”

Internationally, patent US7722756132 of the year 2010 “Process for multiple stage direct electrowinning of Copper” stands out, which relates to a process for the direct electrolytic extraction stage of copper; US7736488132 “Process for recovery of Copper from copper-bearing material using pressure leaching, direct electrowinning and solvent/solution extraction” which relates to a procedure for the recovery of copper from copper-containing material by pressure leaching and extraction direct electrolytic and solvent/solution extraction; and finally patent US807085132 of the year 2011 “Chloride heap leaching” which relates to a method of heap leaching aimed to recover copper from a primary copper sulfide mineral in which the mineral is leached in a chloride solution of acid/sulfate in conditions which require the redox potential of the mineral surface to be below 600 my to cause the sulfide to dissolve into copper.

After these inventions, the dynamics in the extraction activity through leaching in the world has become new concepts, such as bioleaching (using acidophilic bacteria) and leaching with thiosulfate, among others.

In the coming years, the development of the world mining industry will be based on exploiting new basically sulphide mining reserves, for which, at present, the mineral concentration processes are used. As described in the state of the art, compared to concentration, hydrometallurgy is not very competitive, given that the first one allows a recovery of more than 80% in a matter of hours and the second one reaches between 30% and 60% recovery in periods over 300 days. In this sense, it becomes clear that it is crucial for the industry to have technologies that allow greater efficiency and productivity of resources.

Precisely because of all the above, it is that the method proposed by the present invention arises as a new technology, alternative to conventional and highly integral processes, minimizing processing and input cycles and at the same time maximizing simultaneous recoveries of various chemical elements.

SUMMARY OF THE INVENTION

The method consists in the injection of an electron flow that allows the electronic structure of materials to be manipulated, to solubilize the compounds that contain the chemical elements. The release of the chemical elements is finally achieved by washing the previously solubilized material in neutral water.

The method is based on a quantum property of electronic manipulation that allows modifying the solubility property of a material.

GOLDEST is the nomination of the METHOD when it is applied to extract gold, silver and platinum.

HYPEX is the nomination of the METHOD when it is applied to extract any other kind of chemical elements.

