A method for recovering valuable elements using a ferric methanesulfonate leaching agent

Abstract

The present application relates to a method for recovering valuable elements by using iron methanesulfonate system leaching agent. The method comprises: mixing iron methanesulfonate system leaching agent with material containing valuable element M to obtain leaching solution and leaching residue; the iron methanesulfonate system leaching agent is an acidic solution comprising methanesulfonic acid and Fe 3+ ; the leaching solution is electrolyzed at a cathode, M ions are reduced and precipitated to obtain M metal, the electrolyzed leaching solution is electrolyzed at an anode, Fe 2+ is oxidized to Fe 3+ , a regenerated iron methanesulfonate system leaching agent is obtained, and is reused as the leaching agent. The present application uses Fe 3+ as an oxidizing agent, and green non-oxidizing organic acid methanesulfonic acid as a leaching medium, thereby realizing efficient leaching of M elements; further combining with an electrolysis process to recover valuable element metal, thereby realizing efficient short-process green recovery of valuable element metal, and avoiding problems such as equipment corrosion, high maintenance cost and easy generation of toxic chlorine gas in the process of electrochemical oxidation regeneration from the source.

Description

Technical Field

[0001] This invention relates to the field of hydrometallurgical technology, specifically to the recovery of valuable elements, and more particularly to a method for recovering valuable elements using a ferric methanesulfonate leaching agent. Background Technology

[0002] Fe 3+ As a commonly used oxidant, it is widely used in the field of organometallic secondary resource recycling due to its advantages such as stable valence state, moderate oxidizing power, and mild reaction conditions.

[0003] CN106755999A discloses a microwave-enhanced leaching method for chalcopyrite, comprising the following steps: 1) mixing chalcopyrite with a particle size less than 0.074 mm with a leaching agent solution to obtain a mixed slurry; 2) subjecting the mixed slurry to microwave-enhanced leaching treatment, and filtering after leaching to obtain a copper-containing leachate. This invention uses an aqueous solution of ferric sulfate and sulfuric acid as the leaching agent solution, enabling the leaching and extraction of copper from low-grade copper ores that are difficult to smelt using pyrometallurgical processes. Furthermore, the entire process does not produce gases such as sulfur dioxide, making it environmentally friendly, simple to operate, with a short production cycle, and low requirements for equipment corrosion resistance. In addition, this method can mitigate the "passivation" phenomenon, resulting in a high copper leaching rate and promising application prospects.

[0004] CN109943721A discloses a low-acid leaching process for copper in electronic waste, comprising: physical dismantling of electronic waste - crushing - screening - ferric sulfate leaching - displacement or extraction - electrowinning. This process uses ferric sulfate as the leaching agent under low-acid conditions, with the leaching reaction occurring at room temperature and pressure. The acid generated by the hydrolysis of ferric sulfate balances the acid consumption reaction of the electronic waste. The strong oxidizing property of ferric sulfate under acidic conditions oxidizes and dissolves the fine copper particles in the electronic waste. Copper is then recovered through displacement, extraction, or electrowinning, demonstrating excellent leaching efficiency for metallic copper in electronic waste.

[0005] CN112458280A discloses a method for enriching precious metals from impure materials. This method first adds anhydrous ferric chloride to the impure material, then selectively leaches most of the nickel using a wet process. Subsequently, a pyrometallurgical process is used to obtain a nickel-iron alloy containing precious metals. Finally, the nickel-iron metal in the nickel-iron powder is leached with ferric chloride, yielding a precious metal concentrate and a leachate primarily composed of ferrous chloride. This process has advantages such as simple operation, high overall recovery rate, high precious metal enrichment ratio, environmental friendliness, and low cost.

[0006] In existing technologies based on Fe 3+ Leaching agents often use sulfuric acid or hydrochloric acid as the medium, and Fe is commonly used. 3+Leaching agents mainly include Fe2(SO4)3 and FeCl3. While Fe2(SO4)3 leaching has advantages such as being environmentally friendly and low-cost, it suffers from problems including easy passivation of the leaching interface and low leaching rates for certain valuable elements, such as Ag and Pb. FeCl3 leaching, on the other hand, offers advantages such as high efficiency, high overall recovery rate, and recyclable reagents, but it also suffers from severe equipment corrosion, high equipment maintenance costs, unsuitability for treating Ag and Pb-containing waste, and the potential generation of toxic chlorine gas during the electro-oxidation regeneration process. Therefore, there is an urgent need to develop a greener, more efficient, and more adaptable method for iron system recovery. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a method for recovering valuable elements using a ferric methanesulfonate leaching agent. This invention utilizes Fe... 3+ Using methanesulfonic acid, a green, non-toxic, and biodegradable non-oxidizing organic acid, as the leaching medium, a ferric methanesulfonate leaching agent is formulated for leaching materials containing valuable element M, achieving efficient leaching of element M. Furthermore, by combining electrolysis with the recovery of valuable metals and simultaneously completing the oxidative regeneration of the ferric methanesulfonate leaching agent, efficient, short-process, and green recovery of valuable metals and the cyclic regeneration of the leaching agent are achieved. This avoids problems such as equipment corrosion, high maintenance costs, and the generation of toxic chlorine gas during the electro-oxidation regeneration process from the source.

[0008] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for recovering valuable elements using a ferric methanesulfonate leaching agent, the method comprising: (1) Leaching: A leaching reaction is carried out with a mixed ferric methanesulfonate leaching agent and a material containing a valence element M to obtain a leachate and a leaching residue; the ferric methanesulfonate leaching agent comprises methanesulfonic acid and Fe. 3+ An acidic solution; in the ferric methanesulfonate leaching agent, Fe 3+ The concentration of [amount] is above 0.1 mol / L, and the concentration of methanesulfonic acid is above 0.1 mol / L; the valuable element M can be [converted] by Fe [removal / removal]. 3+ Oxidation generates M ions that are soluble in the ferric methanesulfonate leaching agent; and M ions preferentially dissolve in acidic aqueous solutions compared to Fe. 2+ It is reduced and deposited by electrolysis.

[0009] (2) Electrolysis: The leachate obtained in step (1) is electrolyzed. The electrolysis is performed in a diaphragm electrolytic cell. The cathode electrolyte is the leachate, and the anolyte includes methanesulfonic acid and Fe. 2+ The M ions are reduced and deposited at the cathode to obtain M metal; the Fe in the anolyte 2+ It is oxidized to Fe at the anode 3+The regenerated ferric methanesulfonate leaching agent is obtained and reused in step (1).

[0010] This invention utilizes the high solubility and strong stability of methanesulfonates (such as iron, copper, silver, and tin), using methanesulfonic acid as the leaching medium, and employing a mixture of methanesulfonic acid and Fe... 3+ The ferric methanesulfonate leaching agent was used to leach materials containing the valence element M, achieving highly efficient leaching of M. Then, the leaching solution was used as the cathode electrolyte to electrolytically reduce and precipitate the M metal, while simultaneously using Fe-containing... 2+ The anolyte, after anodic oxidation, yields a Fe-containing solution. 3+ The regenerated leachate, while yielding M metal, completes the valence state cycle of Fe and is reused in the leaching process, realizing the recycling of the leaching agent.

[0011] The method provided by this invention uses Fe 3+ Using Fe as an oxidant, the leaching agent of the iron methanesulfonate system is recycled through the valence state cycle of Fe, truly realizing the efficient, short-process, and green recovery of valuable element M, with no waste liquid generated, resulting in significant economic and social benefits. Using green, non-oxidizing organic acid as the leaching medium, methanesulfonic acid is stable under electrolysis conditions and will not be oxidized or reduced, avoiding the decomposition and loss of the leaching agent, thus fundamentally avoiding the generation of toxic gases and problems such as equipment corrosion and high maintenance costs.

[0012] Preferably, the valuable element M includes any one or a combination of at least two of silver, copper, or tin.

[0013] Preferably, the electrolytic cell is divided into an anode chamber and a cathode chamber by a diaphragm. The leachate is first electrolyzed in the cathode chamber to extract metal M, and then enters the anode chamber as the anode electrolyte for electrolytic oxidation to obtain the regenerated iron methanesulfonate system leachate.

[0014] Preferably, the liquid-to-solid ratio of the material containing valence element M to the leachate in step (1) is 1 mL / g to 20 mL / g.

[0015] Preferably, the leaching temperature in step (1) is 20 ℃ to 95 ℃.

[0016] Preferably, the leaching time in step (1) is 10 min to 240 min.

[0017] Preferably, the anode current density of the diaphragm electrolyzer in step (2) is 100 A / m. 2 ~4000 A / m 2 .

[0018] Preferably, the cathode current density of the diaphragm electrolytic cell in step (2) is 50 A / m. 2 ~1000 A / m 2.

[0019] Preferably, the method further includes purifying the leachate obtained in step (1) before electrolysis in step (2).

[0020] Preferably, the purification process includes chemical removal and / or adsorption removal.

[0021] Compared with the prior art, the present invention has the following beneficial effects: (1) This invention uses methanesulfonic acid as the leaching medium and Fe... 3+ Using methanesulfonates (such as iron, copper, silver, and tin) as oxidants, a highly stable leaching system was constructed, leveraging their high solubility and stability. This ensures the reliability and environmental friendliness of the entire leaching-recovery-regeneration cycle. Furthermore, compared to existing Fe2(SO4)3 and FeCl3 leaching systems, this significantly improves the efficiency of Fe leaching. 3+ The cyclic reliability, stability, and feedstock adaptability of the leaching system.

[0022] (2) The method provided by the present invention uses Fe 3+ Using Fe as an oxidant, the efficient, short-process, and green recovery of valuable element M and the recycling of ferric methanesulfonate leaching agent are simultaneously achieved through the valence state cycle of Fe, significantly reducing reagent consumption and process waste discharge. In addition, the green non-oxidizing methanesulfonate ion has extremely high chemical stability in aqueous solution and is not prone to redox reactions, thus avoiding the decomposition and loss of leaching agent and fundamentally avoiding the generation of toxic gases, equipment corrosion, and high maintenance costs. Detailed Implementation

[0023] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention.

[0024] The "range" disclosed in this invention can be defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of the specific range. This type of range definition can include or exclude endpoints; any endpoint can be independently included or excluded, and they can be arbitrarily combined, meaning any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60~120 and 80~110 are listed for specific parameters, it is understood that ranges of 60~110 and 80~120 are also expected. Furthermore, if minimum range values ​​1 and 2 are listed, and maximum range values ​​3, 4, and 5 are also listed, then the following ranges are all expected: 1~3, 1~4, 1~5, 2~3, 2~4, and 2~5. In this invention, unless otherwise stated, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0~5" indicates that all real numbers between "0" and "5" have been listed in this article; "0~5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is described as an integer ≥2, it is equivalent to listing integers such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc. For instance, when a parameter is described as an integer selected from "2~10", it is equivalent to listing the integers 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0025] In this invention, "a combination of at least two" refers to a quantity greater than or equal to two, unless otherwise specified. For example, "any combination of one or at least two" means one or more or more items. It can be understood that when referring to "a combination of at least two," it refers to any suitable combination of multiple items, that is, a combination of "at least two" items carried out in a manner that does not conflict with and enables the implementation of this invention.

[0026] Unless otherwise specified, all embodiments and optional embodiments of the present invention can be combined with each other to form new technical solutions.

[0027] The term "embodiment" as used in this invention means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment or implementation of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this invention can be combined with other embodiments.

[0028] Those skilled in the art will understand that the order in which the steps are written in the methods of the various embodiments does not imply a strict execution order. The detailed execution order of each step should be determined by its function and possible internal logic. Unless otherwise specified, all steps of the present invention may be performed sequentially or randomly, but are preferably performed sequentially. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the method may also include step (c), meaning that step (c) can be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0029] In this invention, open-ended technical features or solutions described using terms such as "comprising" do not exclude additional members beyond those listed unless otherwise specified. They can be considered as providing both closed-ended features or solutions comprised of the listed members and open-ended features or solutions that include additional members beyond the listed members. For example, A includes a1, a2, and a3. Unless otherwise specified, it may also include other members or exclude additional members. This can be considered as providing both technical features or solutions where "A is composed of a1, a2, and a3" or "A is selected from a1, a2, and a3," and technical features or solutions where "A includes not only a1, a2, and a3, but also other members."

[0030] In this invention, unless otherwise specified, the features or solutions corresponding to "and / or" include any one of two or more of the related listed items, as well as any and all combinations of the related listed items. These arbitrary and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. For example, "A and / or B" represents a group consisting of A, B, and "a combination of A and B". "Containing A and / or B" can mean "containing A, containing B, and containing A and B", or "containing A, containing B, or containing A and B", and can be appropriately understood according to the context.

[0031] In this invention, the term "first aspect" is used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should it be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first" and the like serve only as a non-exhaustive enumerative description and should be understood not to constitute a closed limitation on quantity.

[0032] In this invention, "optional" means that something is optional, that is, it refers to any one of the two parallel solutions of "having" or "not having". If there are multiple "optional" options in a technical solution, unless otherwise specified, and there are no contradictions or mutual constraints, then each "optional" option is independent.

[0033] In this invention, "room temperature" generally refers to 4℃~35℃, and may refer to 20℃±5℃. In some embodiments of this invention, room temperature refers to 20℃~30℃.

[0034] In one specific embodiment, the present invention provides a method for recovering valuable elements using a ferric methanesulfonate leaching agent, the method comprising: (1) Leaching: A leaching reaction is carried out with a mixed ferric methanesulfonate leaching agent and a material containing a valence element M to obtain a leachate and a leaching residue; the ferric methanesulfonate leaching agent comprises methanesulfonic acid and Fe. 3+ An acidic solution; in the ferric methanesulfonate leaching agent, Fe 3+ The concentration of [amount] is above 0.1 mol / L, and the concentration of methanesulfonic acid is above 0.1 mol / L; the valuable element M can be [converted] by Fe [removal / removal]. 3+ Oxidation generates M ions that are soluble in the ferric methanesulfonate leaching agent; and M ions preferentially dissolve in acidic aqueous solutions compared to Fe. 2+ It is electrolytically reduced and deposited; The valuable element M includes any one or a combination of at least two of silver, copper, or tin.

[0035] (2) Electrolysis: The leachate obtained in step (1) is electrolyzed. The electrolysis is performed in a diaphragm electrolytic cell. The cathode electrolyte is the leachate, and the anolyte includes methanesulfonic acid and Fe. 2+ The M ions are reduced and deposited at the cathode to obtain M metal; the Fe in the anolyte 2+ It is oxidized to Fe at the anode 3+ The regenerated ferric methanesulfonate leaching agent is obtained and reused in step (1).

[0036] This invention utilizes the high solubility and strong stability of methanesulfonates (such as iron, copper, silver, and tin), using methanesulfonic acid as the leaching medium, and employing a mixture of methanesulfonic acid and Fe... 3+ The ferric methanesulfonate leaching agent was used to leach materials containing the valence element M, achieving highly efficient leaching of M. Then, the leaching solution was used as the cathode electrolyte to electrolytically reduce and precipitate the M metal, while simultaneously using Fe-containing... 2+ The anolyte, after anodic oxidation, yields a Fe-containing solution. 3+ The regenerated leachate, while yielding M metal, also completes the valence state cycle of Fe and is reused in the leaching process.

[0037] In the method provided by this invention, the Fe in the ferric methanesulfonate leaching agent 3+ While oxidizing valuable elements in waste containing valuable elements into valuable element ions, they are simultaneously reduced to Fe. 2+ That is, the leachate contains valuable element ions and Fe. 2+ During electrolysis, after valuable element ions are electrolytically reduced and precipitated as valuable element metals, the remaining components in the leachate include methanesulfonic acid and Fe. 2+ It can be reused in the anolyte during subsequent electrolysis processes; Fe in the anolyte 2+ Oxidized into Fe 3+ The composition of the anolyte after electrolysis includes methanesulfonic acid and Fe. 3+ The resulting recycled ferric methanesulfonate leaching agent is reused in the leaching stage to leach valuable elements.

[0038] The method provided by this invention achieves Fe through electrolysis. 2+ with Fe 3+ The dynamic cycle of valence states enables the recycling of the ferric methanesulfonate leaching agent → leaching solution → anolyte → ferric methanesulfonate leaching agent. This means the method provided by this invention truly achieves efficient, short-process, and green recovery of valuable elements, with no waste liquid produced, significantly reducing reagent consumption and wastewater treatment costs. Using a green, non-oxidizing organic acid as the leaching medium, methanesulfonic acid remains stable under electrolysis conditions and will not be oxidized or reduced, avoiding the decomposition and loss of the leaching agent. This fundamentally prevents the generation of toxic gases and eliminates the disadvantages of equipment corrosion and high maintenance costs.

[0039] In this invention, by controlling the concentration of methanesulfonic acid in the ferric methanesulfonate leaching agent, the Fe... 3+ The concentration of the ferric methanesulfonic acid leaching agent is above 0.1 mol / L, for example, it can be 0.1 mol / L, 0.5 mol / L, 1 mol / L, 2 mol / L, 3 mol / L, 4 mol / L, or 5 mol / L, to adjust the pH of the ferric methanesulfonic acid leaching agent and avoid Fe 3+ Hydrolysis occurs. In the ferric methanesulfonate leaching agent, Fe... 3+ From CH3SO3 - Balance.

[0040] In some embodiments, the valuable element M includes any one or a combination of at least two of silver, copper, or tin.

[0041] In some embodiments, the electrolytic cell is divided into an anode chamber and a cathode chamber by a diaphragm. The leachate is first electrolyzed in the cathode chamber to extract metal M, and then enters the anode chamber as the anode electrolyte for electrolytic oxidation to obtain a regenerated iron methanesulfonate system leachate.

[0042] In some embodiments, the liquid-solid ratio of the material containing valence element M in step (1) to the leachate is 1 mL / g to 20 mL / g, for example, it can be 1 mL / g, 3 mL / g, 5 mL / g, 7 mL / g, 9 mL / g, 10 mL / g, 12 mL / g, 14 mL / g, 16 mL / g, 18 mL / g or 20 mL / g.

[0043] In some embodiments, the leaching temperature in step (1) is 20 ℃ to 95 ℃, for example, it can be 20 ℃, 30 ℃, 40 ℃, 50 ℃, 60 ℃, 70 ℃, 80 ℃, 90 ℃ or 95 ℃.

[0044] In some embodiments, the leaching time in step (1) is 10 min to 240 min, for example, it can be 10 min, 20 min, 40 min, 60 min, 80 min, 100 min, 120 min, 140 min, 160 min, 180 min, 200 min, 220 min or 240 min.

[0045] In some embodiments, the anolyte current density of the diaphragm electrolyzer in step (2) is 100 A / m. 2 ~4000A / m 2 For example, it could be 100 A / m 2 200 A / m 2 300 A / m 2 500 A / m 2 1000 A / m 2 1500 A / m 2 2000 A / m 2 2500 A / m 2 3000 A / m 2 3500 A / m 2 Or 4000 A / m 2 .

[0046] In some embodiments, the cathode current density of the electrolytic cell in step (2) is 50 A / m. 2 ~1000 A / m 2 For example, it could be 50 A / m 2 100 A / m 2200 A / m 2 300 A / m 2 400 A / m 2 500 A / m 2 600 A / m 2 700 A / m 2 800 A / m 2 900 A / m 2 Or 1000 A / m 2 .

[0047] In some embodiments, the method further includes purifying the leachate obtained in step (1) before electrolysis in step (2).

[0048] In some embodiments, the purification process includes chemical removal and / or adsorption removal.

[0049] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0050] Example 1 This embodiment provides a method for recovering valuable elements using a ferric methanesulfonate leaching agent. The method includes: (1) Leaching: According to the liquid-to-solid ratio of 2 mL / g, Fe 3+ A leaching agent consisting of ferric methanesulfonate with a concentration of 2.0 mol / L and methanesulfonic acid with a concentration of 0.5 mol / L was mixed with waste containing 25 wt% silver and leached for 60 min at a temperature of 70 ℃. After leaching, the liquid and solid were separated to obtain a clear leachate with an Ag leaching rate of 99.99%. (2) The leachate obtained in step (1) is added to an anion exchange membrane electrolyzer as the cathode electrolyte, containing Fe. 2+ With methanesulfonic acid solution as the anolyte, titanium sheet and graphite electrode as the cathode and anode respectively, and an anolyte current density of 4000 A / m 2 and cathode current density 1000 A / m 2 Electrolysis is carried out under the conditions of Ag + The silver was electrically reduced to metallic silver at the cathode with a current efficiency of 99.73%, and the prepared metallic silver had a purity of 99.99%. 2+ It is oxidized to Fe at the anode 3+ Fe after cathode chamber electrolysis 2+ The solution, serving as the anolyte to be electrolyzed, ultimately enters the anode chamber for electrolytic oxidation, forming 2.0 mol / L Fe. 3+ and mesylate concentration The 0.1 mol / L ferric methanesulfonate leaching agent is recycled for leaching in step (1).

[0051] Example 2 This embodiment provides a method for recovering valuable elements using a ferric methanesulfonate leaching agent. The method includes: (1) Leaching: According to the liquid-solid ratio of 5 mL / g, Fe 3+ A leaching agent consisting of ferric methanesulfonate (1.2 mol / L) and 0.1 mol / L methanesulfonic acid was mixed with waste containing 15 wt% silver and leached for 180 min at a temperature of 40 ℃. After leaching, the liquid and solid were separated to obtain a clear leachate with an Ag leaching rate of 99.98%. (2) The leachate obtained in step (1) is added to a cation exchange membrane electrolyzer as the cathode electrolyte, containing Fe 2+ With methanesulfonic acid solution as the anolyte, titanium sheet and graphite electrode as the cathode and anode respectively, and an anolyte current density of 500 A / m 2 and cathode current density 250 A / m 2 Electrolysis is carried out under the conditions of Ag + The silver was electrically reduced to metallic silver at the cathode with a current efficiency of 99.33%, and the prepared metallic silver had a purity of 99.99%. 2+ It is oxidized to Fe at the anode 3+ Fe after cathode chamber electrolysis 2+ The solution, used as the anolyte for electrolysis, ultimately enters the anode chamber for electrolytic oxidation, forming 1.2 mol / L Fe. 3+ and mesylate concentration The 0.1 mol / L ferric methanesulfonate leaching agent is recycled for leaching in step (1).

[0052] Example 3 This embodiment provides a method for recovering valuable elements using a ferric methanesulfonate leaching agent. The method includes: (1) Leaching: According to the liquid-to-solid ratio of 20 mL / g, Fe 3+ A leaching agent consisting of 0.1 mol / L ferric methanesulfonate and 0.1 mol / L methanesulfonic acid was mixed with waste containing 0.5 wt% silver and leached for 10 min at a temperature of 95 ℃. After leaching, the liquid and solid were separated to obtain a clear leachate with an Ag leaching rate of 99.95%. (2) The leachate obtained in step (1) is added to a diaphragm electrolytic cell as the cathode electrolyte, with a porous membrane as the diaphragm, containing Fe 2+With methanesulfonic acid solution as the anolyte, titanium sheet and graphite electrode as the cathode and anode respectively, and an anolyte current density of 100 A / m 2 and cathode current density 50 A / m 2 Electrolysis is carried out under the conditions of Ag + The silver was electrically reduced to metallic silver at the cathode with a current efficiency of 99.13%, and the prepared metallic silver had a purity of 99.99%. 2+ It is oxidized to Fe at the anode 3+ Fe after cathode chamber electrolysis 2+ The solution, used as the anolyte to be electrolyzed, ultimately enters the anode chamber for electrolytic oxidation, forming 0.1 mol / L Fe. 3+ and mesylate concentration The 0.1 mol / L ferric methanesulfonate leaching agent is recycled for leaching in step (1).

[0053] Example 4 This embodiment provides a method for recovering valuable elements using a ferric methanesulfonate leaching agent. The method includes: (1) Leaching: According to the liquid-solid ratio of 5 mL / g, Fe 3+ A leaching agent consisting of 1.0 mol / L ferric methanesulfonate and 0.1 mol / L methanesulfonic acid was mixed with waste containing 10 wt% silver and leached for 120 min at a temperature of 70 ℃. After leaching, the liquid and solid were separated to obtain a clear leachate with an Ag leaching rate of 99.98%. (2) Add the leachate obtained in step (1) to a diaphragm electrolytic cell containing Fe 2+ With methanesulfonic acid solution as the anolyte, titanium sheet and graphite electrode as the cathode and anode respectively, and an anolyte current density of 400 A / m 2 and cathode current density 200 A / m 2 Electrolysis is carried out under the conditions of Ag + The silver was electrically reduced to metallic silver at the cathode with a current efficiency of 99.03%, and the prepared metallic silver had a purity of 99.99%. 2+ It is oxidized to Fe at the anode 3+ Fe after cathode chamber electrolysis 2+ The solution, used as the anolyte to be electrolyzed, ultimately enters the anode chamber for electrolytic oxidation, forming a 1.0 mol / L Fe... 3+ and mesylate concentration The 0.1 mol / L ferric methanesulfonate leaching agent is recycled for leaching in step (1).

[0054] Example 5 This embodiment provides a method for recovering valuable elements using a ferric methanesulfonate leaching agent. The method includes: (1) Leaching: According to the liquid-to-solid ratio of 8 mL / g, Fe 3+ A leaching agent consisting of 1.5 mol / L ferric methanesulfonate and 0.5 mol / L methanesulfonic acid was mixed with waste containing 30 wt% copper and leached for 240 min at a temperature of 20 ℃. After leaching, the liquid and solid were separated to obtain a clear leachate with a Cu leaching rate of 99.99%. (2) The leachate obtained in step (1) is added to an anion exchange membrane electrolyzer as the cathode electrolyte, containing Fe. 2+ With methanesulfonic acid solution as the anolyte, titanium sheet and graphite electrode as the cathode and anode respectively, and an anolyte current density of 600 A / m 2 and cathode current density 300 A / m 2 Electrolysis is carried out under the conditions of Cu 2+ The copper is electrically reduced to metallic copper at the cathode with a current efficiency of 99.73%, and the prepared metallic copper has a purity of 99.99%. 2+ It is oxidized to Fe at the anode 3+ Fe after cathode chamber electrolysis 2+ The solution, used as the anolyte to be electrolyzed, ultimately enters the anode chamber for electrolytic oxidation, forming a 1.5 mol / L Fe... 3+ and mesylate concentration The 0.1 mol / L ferric methanesulfonate leaching agent is recycled for leaching in step (1).

[0055] Example 6 This embodiment provides a method for recovering valuable elements using a ferric methanesulfonate leaching agent. The method includes: (1) Leaching: According to the liquid-to-solid ratio of 3 mL / g, Fe 3+ A leaching agent consisting of ferric methanesulfonate with a concentration of 2.5 mol / L and methanesulfonic acid with a concentration of 0.5 mol / L was mixed with waste containing 20 wt% copper and leached for 120 min at a temperature of 60 ℃. After leaching, the liquid and solid were separated to obtain a clear leachate with a Cu leaching rate of 99.98%. (2) The leachate obtained in step (1) is added to an anion exchange membrane electrolyzer as the cathode electrolyte, containing Fe. 2+ With methanesulfonic acid solution as the anolyte, titanium sheet and graphite electrode as the cathode and anode respectively, and an anolyte current density of 500 A / m 2 and cathode current density 250 A / m 2 Electrolysis is carried out under the conditions of Cu 2+ The electroreduction of titanium sheets to metallic Cu achieved a current efficiency of 99.78%, and the resulting metallic Cu had a purity of 99.99%. Fe... 2+It is oxidized to Fe at the anode 3+ Fe after cathode chamber electrolysis 2+ The solution, used as the anolyte for electrolysis, ultimately enters the anode chamber for electrolytic oxidation, forming a 2.5 mol / L Fe... 3+ and mesylate concentration The 0.1 mol / L iron methanesulfonate system leaching agent is recycled for leaching in step (1).

[0056] Example 7 This embodiment provides a method for recovering valuable elements using a ferric methanesulfonate leaching agent. The method includes: (1) Leaching: According to the liquid-solid ratio of 4 mL / g, Fe 3+ A leaching agent consisting of ferric methanesulfonate (1.5 mol / L) and ferric methanesulfonate (0.2 mol / L) was mixed with waste containing 30 wt% tin and leached for 60 min at a temperature of 60 ℃. After leaching, the liquid and solid were separated to obtain a clear leachate with a Sn leaching rate of 99.99%. (2) The leachate obtained in step (1) is added to an anion exchange membrane electrolyzer as the cathode electrolyte, containing Fe. 2+ Using methanesulfonic acid solution as the anolyte, titanium sheets and titanium-coated ruthenium-iridium electrodes serve as the cathode and anode, respectively, with an anolyte current density of 600 A / m. 2 and cathode current density 300 A / m 2 Electrolysis is carried out under the conditions of Sn 2+ Tin is electroreduced to metallic tin at the cathode with a current efficiency of 99.71% and a purity of 99.99%. 2+ It is oxidized to Fe at the anode 3+ Fe after cathode chamber electrolysis 2+ The solution, used as the anolyte to be electrolyzed, ultimately enters the anode chamber for electrolytic oxidation, forming a 1.5 mol / L Fe... 3+ and mesylate concentration The 0.1 mol / L ferric methanesulfonate leaching agent is recycled for leaching in step (1).

[0057] Example 8 This embodiment provides a method for recovering valuable elements using a ferric methanesulfonate leaching agent. The method includes: (1) Leaching: According to the liquid-to-solid ratio of 8 mL / g, Fe 3+A leaching agent consisting of 1.8 mol / L ferric methanesulfonate and 0.5 mol / L methanesulfonic acid was mixed with 40 wt% copper-containing waste and leached for 60 min at a temperature of 60 ℃. After leaching, liquid and solid separation was performed to obtain a clear leachate with a Cu leaching rate of 99.98%. Subsequently, the leachate was purified by chemical precipitation combined with an adsorbent. After purification, the leachate was obtained by precision filtration. (2) The purified leachate obtained in step (1) is added to an anion exchange membrane electrolyzer as the cathode electrolyte, containing Fe 2+ With methanesulfonic acid solution as the anolyte, titanium sheet and graphite as the cathode and anode respectively, the anolyte current density is 700 A / m. 2 and cathode current density 350 A / m 2 Electrolysis is carried out under the conditions of Cu 2+ The copper was electrically reduced to metallic silver at the cathode with a current efficiency of 99.63%, and the resulting metallic copper had a purity of 99.99%. Fe... 2+ It is oxidized to Fe at the anode 3+ Fe after cathode chamber electrolysis 2+ The solution, used as the anolyte to be electrolyzed, ultimately enters the anode chamber for electrolytic oxidation, forming 1.8 mol / L Fe. 3+ and mesylate concentration The 0.1 mol / L ferric methanesulfonate leaching agent is recycled for leaching in step (1).

[0058] Comparative Example 1 This comparative example provides a method for recovering valuable elements using a ferric methanesulfonate leaching agent. The method is the same as in Example 1, except that it uses Fe(CH3SO3)3 at a concentration of 0.08 mol / L and CH4O3S at a concentration of 0.08 mol / L as the ferric methanesulfonate leaching agent.

[0059] Comparative Example 2 This comparative example provides a method for recovering valuable elements using a ferric sulfate leaching agent. The method is the same as in Example 1, except that it uses Fe2(SO4)3 with a concentration of 2 mol / L and sulfuric acid with a concentration of 0.5 mol / L as leaching agents.

[0060] Performance testing: The leaching rate, current efficiency, and purity of the recovered valuable element metals were tested in all the above embodiments and comparative examples. The test results are shown in Table 1.

[0061] Table 1 In summary, this invention uses a ferric methanesulfonate leaching agent comprising Fe(CH3SO3)3 and CH4O3S to leach waste containing valuable elements, and recovers the valuable metals through electrolysis, achieving efficient, short-process, and green recycling of valuable metals. This avoids problems such as equipment corrosion, high maintenance costs, and the generation of toxic chlorine gas during the electro-oxidation regeneration process from the source.

[0062] Based on the test results of Example 1, Comparative Examples 1 and 2, if the Fe in the ferric methanesulfonate leaching agent... 3+ If the concentration of methanesulfonic acid is too low, or if a mixed solution of ferric sulfate and sulfuric acid is used to replace the ferric methanesulfonic acid leaching agent in the present invention with an equal concentration, it is impossible to achieve effective recovery of valuable elements.

[0063] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for recovering valuable elements using a ferric methanesulfonate leaching agent, characterized in that, The method includes: (1) Leaching: The leaching agent of the mixed iron methanesulfonate system is reacted with the material containing the valence element M to obtain the leachate and the leaching residue. The leaching agent for the ferric methanesulfonate system includes methanesulfonic acid and Fe. 3+ An acidic solution; in the ferric methanesulfonate leaching agent, Fe 3+ The concentration of [specific substance] is above 0.1 mol / L, and the concentration of methanesulfonic acid is above 0.1 mol / L; The valuable element M can be reacted with Fe. 3+ Oxidation generates M ions that are soluble in the ferric methanesulfonate leaching agent; and M ions preferentially give way to Fe ions in acidic aqueous solutions. 2+ It is electrolytically reduced and deposited; (2) Electrolysis: The leachate obtained in step (1) is electrolyzed. The electrolysis is performed in a diaphragm electrolytic cell. The cathode electrolyte is the leachate, and the anolyte includes methanesulfonic acid and Fe. 2+ ; The M ions are reduced and deposited at the cathode to obtain M metal; Fe in the anolyte 2+ It is oxidized to Fe at the anode 3+ The regenerated ferric methanesulfonate leaching agent is obtained and reused in step (1).

2. The method according to claim 1, characterized in that, The valuable element M includes any one or a combination of at least two of silver, copper, or tin.

3. The method according to claim 1 or 2, characterized in that, The electrolytic cell is divided into an anode chamber and a cathode chamber by a diaphragm. The leachate is first electrolyzed in the cathode chamber to extract metal M, and then enters the anode chamber as the anode electrolyte for electrolytic oxidation to obtain the regenerated iron methanesulfonate system leachate.

4. The method according to any one of claims 1 to 3, characterized in that, In step (1), the liquid-solid ratio of the material containing valence element M to the leachate is 1 mL / g to 20 mL / g, the leaching temperature is 20 ℃ to 95 ℃, and the leaching time is 10 min to 240 min.

5. The method according to any one of claims 1 to 4, characterized in that, The anode current density of the diaphragm electrolyzer in step (2) is 100 A / m 2 ~4000 A / m 2 The cathode current density is 50 A / m 2 ~1000 A / m 2 .

6. The method according to any one of claims 1 to 5, characterized in that, The method further includes purifying the leachate obtained in step (1) before electrolysis in step (2).

7. The method according to claim 6, characterized in that, The purification process includes chemical removal and / or adsorption removal.

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