Process for comprehensive recovery of non-ferrous metals

Abstract

The invention relates to the electrolytic recovery of non-ferrous metals by vortex electrowinning performed in "tubes" organized into a single process cycle. The technical result of the invention is that of providing for more comprehensive recovery of metals from solutions having a low target metal content, thereby permitting an economical use of resources and an increase in product yield. This is achieved in that the claimed process is carried out in a tube or cylindrical electrolytic cell having a slot diffuser, where an electrolyte is circulated between a cathode and an anode by means of a pump, creating a swirling flow, the concentration of target metal in the solution is changed from 60 g / L to a residual concentration of 0.5 g / L, and the temperature of the solution in circulation is restricted to values of no more than 45°С.

Description

[0001] A method for the comprehensive extraction of non-ferrous metals

[0002] The invention relates to the field of electrolytic extraction of non-ferrous metals, based on the technology of vortex electrolysis in “pipes” assembled into a single technological cycle.

[0003] Document CN 109208032 A, dated January 15, 2019, discloses a method for extracting gallium from a gallium-containing alkaline solution by electrolysis. The method comprises the following steps: filtering the gallium-containing alkaline solution using a precision filter device to obtain a filtrate; subjecting the filtrate to cyclone electrolysis to remove gallium and collecting the resulting liquid metallic gallium to obtain a metallic thallium product. According to the invention, gallium is extracted by cyclone electrolysis based on the difference in the theoretical precipitation potential of each metal ion; that is, if the metal being extracted has a large potential difference with ions of other metals in the solution system, the metal with a positive potential is easily and preferentially precipitated on the negative electrode; and the key point is to eliminate the adverse effects of concentration polarization, etc.on electrolysis due to the high-speed flow of the solution, therefore the limitation is that the traditional electrolysis process is affected by many factors such as ion concentration, precipitation potential, concentration polarization, overpotential value, etc.

[0004] Document CN 107557592 A, dated January 9, 2018, describes a method for separating copper and arsenic in high-arsenic lead-copper matte. According to this process, high-arsenic lead-copper matte raw material and iron pyrite are dosed and crushed; the resulting ore powder, sulfuric acid, and dispersing additive are mixed, followed by oxidative acid leaching under pressure, liquid-solid separation, and obtaining a copper-containing leaching liquid and arsenic-containing leaching slag; and the copper-containing leaching liquid is subjected to cyclone electrowinning, thereby obtaining a copper product.

[0005] An electrolyzer is known (RU 90797 U, 20.01.2010) for obtaining nanostructured metal powders, containing a bath, an anode and a cathode, made in the form of a cylindrical spiral, rigidly connected to a rotation drive, the electrolyzer is made with a two-chamber diaphragm, consisting of an anode chamber with an insoluble plastographite anode and a cathode two-layer chamber with a lower aqueous layer containing metal ions, and an upper layer of organic liquid, while a spiral rotating cathode is installed in the cathode chamber, to which an asymmetric alternating current with a characteristic frequency is supplied by means of a sliding contact.

[0006] An electrolyzer is known (KZ 23512 A4, 12 / 15 / 2010) for obtaining metals from pulps, for example, gold, comprising a housing, an anode, a cathode located in the center of the electrolyzer, and a mixing device, wherein the housing is made in the form of a cylinder, the anode in the form of rods installed along the circumference of the cylinder and connected in parallel, the cathode in the form of a hollow rod made of a dielectric material, around which a metal spiral is located, and the mixing device is installed in the center of the hollow rod and is made of a chemically resistant material, the shaft of which contains a metal core.

[0007] The disadvantages of the above technical solutions include the possibility of extracting only one metal, as well as low current efficiency, which results in high energy costs, which affects the economic profitability of production and poses serious risks to the health and safety of workers and the environment.

[0008] The prototype of this technical solution is a method for the comprehensive extraction of non-ferrous metals (KR 20190025136 A, dated March 11, 2019). This invention utilizes vortex electrolysis technology, the process comprising the following steps: adding thiourea and hydrochloric acid to the filtrate to produce an electrolyte; introducing the electrolyte into the vortex electrolysis tank; circulating the electrolyte in the cyclone electrolysis tank; and supplying current to the electrolyzer to precipitate the solid.

[0009] The disadvantage is the insufficient purity and quality of the cathodes, which creates additional difficulties and costs for production processes; additional time and resources are required to achieve the required degree of purity.

[0010] The objective of the invention is to develop a new improved method for the comprehensive extraction of non-ferrous metals while eliminating the above-mentioned disadvantages.

[0011] The technical result of the invention is to increase the complexity of metal extraction from solutions with a low content of the target metal, which makes it possible to economically use resources and increase product yield.

[0012] This is achieved by carrying out the process in a tube or cylindrical electrolytic cell with a slot diffuser, where the electrolyte is pumped between the cathode and anode, creating a vortex flow, while the concentration of the target metal in the solution changes from 60 g / l to a residual concentration of 0.5 g / l, the temperature of the solution in circulation is limited to values ​​no higher than 45 °C.

[0013] The invention is implemented as follows.

[0014] Pilot industrial tests were conducted at the company's production facilities using a comprehensive technology for the extraction of non-ferrous metals, including the use of vortex electrolysis, in which the process was carried out in a tube or cylindrical electrolytic cell with a slot diffuser, where the electrolyte was pumped between the cathode and anode, creating a vortex flow, while the concentration of the target metal in the solution was varied from 60 g / l to a residual concentration of 0.5 g / l, the temperature of the solution in circulation was limited to values ​​​​no higher than 45 ° C. A cylindrical electrolytic cell was used in which an electrode pair was installed

[0015] A cylindrical electrolytic cell with a slot diffuser made of filter fabric, inside which the anode was located, was used.

[0016] In the electrolyte, the metal concentration was controlled by adjusting the pumping speed and introducing fresh electrolyte.

[0017] The cathode was selected depending on the target metal to be extracted.

[0018] An anode made of a copper-lead-calcium electrode was used.

[0019] During pilot industrial testing (using this technology), the dynamic modes of vortex electrolysis made it possible to produce commercial products with high metal purity in the shortest possible time (20% more efficiently), the so-called “vortex” electrolysis technology.

[0020] This technical solution has proven itself in the extraction of metals such as copper, nickel, zinc, silver, etc.

[0021] Vortex electrolysis technology was not limited to the use of industrial solutions with high target metal content. This method was also used to process solutions with low metal concentrations, such as:

[0022] - depleted electrolytes from primary production, for the recovery of metals, which made it possible to reduce losses and ensure their secondary use.

[0023] - industrial waste solutions and effluents that were previously considered impossible and ineffective to use.

[0024] - heap leaching solutions: direct extraction of metals from solutions into marketable products obtained as a result of heap leaching is one of the most important applications of vortex electrolysis.

[0025] - galvanic solutions: this technical solution made it possible to extract and recover metals from spent galvanic solutions, which is an important component of the recycling process. Wastewater: the technology was used to purify wastewater from metallic impurities.

[0026] - Refinery waste and electronic waste: processing electronic waste containing valuable metals, including metal recycling and reuse. This technology allows for the extraction of non-ferrous metals from the electrolyte, ensuring high efficiency, safety, and environmental sustainability in the production of metals of varying purity and origin, in accordance with Article 113 of the Environmental Code of the Republic of Kazakhstan dated January 2, 2021, No. 400-VI ZRK.

Claims

Formula 1. A method for the comprehensive extraction of non-ferrous metals, including the use of vortex electrolysis, characterized in that the process is carried out in a tube or cylindrical electrolytic cell with a slot diffuser, where the electrolyte is pumped between the cathode and the anode, creating a vortex flow, while the concentration of the target metal in the solution is changed from 60 g / l to a residual concentration of 0.5 g / l, the temperature of the solution in circulation is limited to values ​​​​not higher than 45 °C.

2. The method according to paragraph 1, characterized in that a cylindrical electrolytic cell is used in which an electrode pair is installed.

3. The method according to paragraph 1, characterized in that a cylindrical electrolytic cell with a slot diffuser made of filter fabric, inside which an anode is located, is used.

4. The method according to paragraph 1, characterized in that a cylindrical electrolytic cell is used, the body of which is made of stainless steel or titanium.

5. The method according to paragraph 1, characterized in that the metal concentration in the electrolyte is controlled by regulating the pumping speed and the introduction of fresh electrolyte.

6. The method according to paragraph 1, characterized in that the cathode is selected depending on the target metal being extracted.

7. The method according to paragraph 1, characterized in that an anode made of a copper-lead-calcium electrode is used.