A method for recovering high-arsenic indium germanium-containing material
Patent Information
- Application Number
- CN202611324044.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-28
- Publication Date
- 2026-10-13
AI Technical Summary
[0025]本发明通过对预先低温脱砷的物料进行富集浸出，同步实现铟锗与锌镉分离，锌、镉进入浸出液，铟锗富集入渣，浸出液可便于后续梯级分离回收锌和镉。
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Figure CN122898739A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of secondary hazardous waste resource comprehensive recycling technology. Specifically, it relates to a method for efficient recovery of indium, germanium, and associated valuable metals such as lead, zinc, and cadmium from high-arsenic indium-germanium materials after pre-arsenic removal. Background Technology
[0002] High-arsenic indium-germanium (IAG) materials are high-arsenic IEG neutralization and enrichment slags produced during hydrometallurgical processes, or secondary hazardous waste resources high-arsenic IEG-rich IEG resources generated from the high-temperature reduction and volatilization of IEG-containing hazardous waste slag. These materials contain 5–25% As, 0.01–0.5% Ge, and 0.03–3% In, and typically also contain valuable metals such as lead, zinc, and cadmium. Currently, the primary method for recovering these valuable elements is direct wet leaching.
[0003] The widely used direct acid leaching process for high-arsenic indium-germanium materials has many technical bottlenecks: (1) A large amount of arsenic is leached into the leachate along with indium, germanium, zinc, cadmium, etc., making it difficult to separate and recover indium and germanium and resulting in serious losses; (2) Low-content indium and germanium are leached together with zinc, cadmium, and iron, resulting in relatively low indium and germanium content in the subsequent high-concentration zinc, cadmium, and iron solutions, making it difficult to separate and recover them; (3) The residual indium and germanium concentration in the obtained zinc and cadmium-containing leachate is often greater than 2 mg / L, causing indium and germanium loss. At the same time, the residual indium and germanium have a significant impact on zinc electrowinning recovery and will affect the quality of cathode zinc; (4) The current process generally has the problem of indium recovery rate being less than 80% and germanium recovery rate being less than 60%, and the obtained indium products and germanium enrichment have high impurity content and poor product quality; (5) It is difficult for the existing methods to simultaneously ensure high yields of germanium and indium and obtain high-quality indium products and germanium enrichment. Summary of the Invention
[0004] To address the shortcomings of existing technologies, this invention provides a method for recovering high-arsenic indium-germanium materials. Through low-temperature arsenic removal, enrichment leaching, controlled acid dissolution, germanium recovery, and indium recovery processes, arsenic is first pre-removed. After enrichment leaching of the low-arsenic indium-germanium raw material, indium and germanium are efficiently enriched and recovered separately, and the loss of germanium and indium is greatly reduced. This achieves multiple objectives, including efficient centralized separation of arsenic, high pre-enrichment of indium and germanium, efficient leaching of multiple metals, and efficient graded recovery of indium and germanium.
[0005] To achieve the above objectives, the present invention is implemented through the following technical solution:
[0006] The method for recovering high-arsenic indium-germanium materials includes the following steps:
[0007] (1) Arsenic removal;
[0008] (2) Enrichment leaching: After the arsenic removal, the indium-germanium-containing material is mixed with acid and sent into a stirred reactor for enrichment leaching. After the reaction is completed, the reaction slurry is separated into liquid and solid to obtain indium-germanium enriched slag and zinc-rich leachate.
[0009] (3) Controllable acid solubility:
[0010] 1) Stage I high acid leaching: The indium-germanium enriched slag produced in step (2) is mixed with the leachate from stage II and then fed into a stirred reactor for reaction; the Fe content in the solution is controlled. 3+ < 500 mg / L, after the reaction is completed, liquid-solid separation is performed to obtain the first stage leachate and the first stage leach residue;
[0011] 2) Stage II ultra-high acid leaching: The leaching residue from Stage I is mixed with sulfuric acid solution and then fed into a stirred reactor for reaction. Concentrated sulfuric acid is added to the reactor. After the reaction is completed, liquid-solid separation is performed to obtain Stage II leachate and Stage II leaching residue. Stage II leachate is returned to Stage I high acid controlled leaching for slurry preparation.
[0012] (4) Germanium recovery: including:
[0013] 1) Germanium separation and enrichment: Germanium is selectively recovered from the high acid leaching solution in stage I using an ion exchange process to obtain sodium germanate enrichment solution and germanium recovery solution.
[0014] 2) Germanium enrichment and precipitation: The sodium germanate enrichment solution produced in step 1) is pumped into a stirred reactor, and ferric sulfate is added until the germanium concentration in the solution is <2mg / L. After the reaction is completed, the reaction slurry is subjected to liquid-solid separation to obtain the germanium enrichment.
[0015] (5) Indium recovery: Indium is selectively recovered from germanium recovery liquid using solvent extraction process to obtain high indium back-extraction liquid and indium extraction residue.
[0016] Furthermore, in step (3), the sulfuric acid concentration of the leachate in stage I is 10–80 g / L, and the sulfuric acid concentration of the leachate in stage II is 120–200 g / L.
[0017] Furthermore, in step (3), the first stage of high-acid leaching is controlled by introducing liquefied SO2 to regulate the Fe content in the solution. 3+ < 500 mg / L.
[0018] Furthermore, in step (4), germanium separation and enrichment adopts an ion exchange process of adsorption-deep washing-alkaline desorption.
[0019] Furthermore, the indium extraction residue from step (5) is returned to step (2).
[0020] Furthermore, the arsenic removal in step (1) specifically involves continuously feeding high-arsenic indium-germanium materials into a medium-low temperature closed belt reactor. At medium-low temperatures, the low-valence arsenic oxides in the high-arsenic indium-germanium materials continuously volatilize and accumulate in the flue, resulting in crude arsenic trioxide and low-arsenic indium-germanium materials.
[0021] Furthermore, the low-arsenic indium-germanium material produced in step (1) contains less than 0.5% arsenic.
[0022] Furthermore, the acid solution in step (2) is the indium extraction residue or a mixture of indium extraction residue and sulfuric acid solution. The concentrations of indium and germanium in the produced zinc-rich leachate are both < 2 mg / L. The indium-germanium enriched slag contains 0.03-1.5% Ge and 0.09-12% In.
[0023] Furthermore, high-arsenic indium-germanium materials are secondary hazardous waste resources of high-arsenic indium-germanium produced by high-arsenic indium-germanium neutralization and enrichment slag or indium-germanium hazardous waste slag generated in hydrometallurgical processes through high-temperature reduction and volatilization. The indium-germanium materials contain 5-25% As, 0.01-0.5% Ge, 0.03-3% In, 20-35% Pb, 15-40% Zn, 3-15% Cd, and 1-5% Fe.
[0024] The beneficial effects of this invention are:
[0025] This invention achieves simultaneous separation of indium and germanium from zinc and cadmium by enriching and leaching pre-low-temperature arsenic-removed materials. Zinc and cadmium enter the leachate, while indium and germanium are enriched and added to the slag. The leachate facilitates subsequent cascade separation and recovery of zinc and cadmium.
[0026] This invention involves leaching the indium-germanium enriched slag through two stages of high acid leaching, controlling the high acid leaching stage I and the ultra-high acid leaching stage II respectively. The resulting leachate from stage I can be directly used for germanium and indium recovery without additional treatment. Furthermore, the leachate from stage I can effectively reduce the loss of germanium and indium during subsequent germanium and indium recovery, achieving a high germanium and indium recovery rate. In particular, compared to existing processes, there is virtually no loss of indium.
[0027] The technical solution of this invention not only solves the technical problems of difficult separation of arsenic, indium, and germanium caused by arsenic, serious loss of indium and germanium, and the creation of new secondary arsenic hazardous waste, but also achieves efficient cascade separation and recovery of indium, germanium, zinc, cadmium, lead, etc. Attached Figure Description
[0028] Figure 1 This is a simplified process flow diagram of the method for recovering high-arsenic indium-germanium materials according to an embodiment of the present invention. Detailed Implementation
[0029] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are all within the scope of protection of this invention.
[0030] The method for recovering high-arsenic indium-germanium materials of the present invention includes the following steps:
[0031] (1) Low-temperature arsenic removal: High-arsenic indium-germanium material containing 5-25% As, 0.01-0.5% Ge, 0.03-3% In, 20-35% Pb, 15-40% Zn, 3-15% Cd, and 1-5% Fe is continuously transported into a medium-low temperature closed belt reactor via a belt conveyor. At a medium-low temperature of 300-500℃, the low-valence arsenic oxides in the high-arsenic indium-germanium material continuously volatilize and enter the flue to be enriched, resulting in crude arsenic trioxide and low-arsenic indium-germanium material containing <0.5% arsenic.
[0032] Low-temperature pre-arsenic removal ensures efficient arsenic volatilization. At this temperature, indium, germanium, lead, zinc, etc. are all retained in the volatilization residue, while reducing the cost of pre-arsenic removal. The use of a low-temperature closed belt reactor also ensures operational safety and allows for the centralized collection of crude arsenic trioxide.
[0033] (2) Enrichment leaching: The low-arsenic indium-germanium material produced in step (1) is mixed with the indium extraction residue and sent to a stirred reactor for enrichment leaching. The reaction temperature is controlled at 50-80℃ and the reaction is carried out for 1-2 hours. Sulfuric acid solution is continuously added during the process until the concentration of indium and germanium in the zinc-rich leaching solution is < 2 mg / L. After the reaction is completed, the reaction slurry is separated into liquid and solid to obtain indium-germanium enriched slag containing 0.03-1.5% Ge and 0.09-12% In and zinc-rich leaching solution. The zinc-rich leaching solution is replaced with zinc powder and electrowinning, and zinc and cadmium are recovered in the form of cathode zinc and sponge cadmium, respectively.
[0034] The purpose of enrichment leaching is to efficiently separate indium, germanium, and lead from zinc and cadmium. Most of the zinc and cadmium in the material dissolve into the leaching solution, resulting in indium and germanium enriched residue. By controlling the acidity of the leaching system, the concentrations of indium and germanium in the leaching solution are both < 2 mg / L. This ensures efficient enrichment of indium and germanium and eliminates the adverse effects of excessive indium and germanium in the leaching solution on the subsequent production of cathode zinc.
[0035] (3) Controllable acid solubility:
[0036] 1) High-acid controlled leaching in stage I: The indium-germanium enriched slag produced in step (2) is mixed with the leachate from stage II and then fed into a stirred reactor for reaction. The reaction temperature is controlled at 70-90℃ and the reaction time is 1-3 hours. During the reaction, liquefied SO2 is continuously introduced into the reactor until the leaching solution contains Fe 3+ < 500 mg / L, after the reaction, liquid-solid separation was performed to obtain a first-stage leachate and a first-stage leach residue with a sulfuric acid concentration of 60-100 g / L;
[0037] 2) Stage II ultra-high acid leaching: The Stage I leaching residue is mixed with sulfuric acid solution and then fed into a stirred reactor for reaction. The reaction temperature is controlled at 70–90℃, and the reaction time is 1–2 hours. Sulfuric acid solution is continuously added as needed to control the acidity of the leaching solution at the endpoint. After the reaction, liquid-solid separation is performed to obtain Stage II leaching solution and Stage II leaching residue with a sulfuric acid concentration of 120–200 g / L. The Stage II leaching residue contains 51%–55% lead and can be returned to the lead smelting system to produce lead ingots.
[0038] This step yields a first-stage leachate that can be used directly for germanium and indium recovery without pretreatment, and it does not cause any loss of germanium and indium during indium and germanium recovery.
[0039] (4) Germanium recovery:
[0040] 1) Germanium Separation and Enrichment: An ion exchange process involving adsorption-deep washing-alkaline desorption is used to selectively recover germanium from the first-stage leachate. The possible operating procedure is as follows: The first-stage leachate is passed through an ion exchange column at a flow rate of 2–4 BV using a macroporous anion exchange resin, yielding a germanium-recovered solution and a germanium-loaded resin. The residual germanium concentration in the recovered solution is controlled to be <2 mg / L. The germanium-loaded resin is washed with a weak acid solution at pH 1–3, and the washing solution is returned to the enrichment leaching process. A 5%–15% sodium hydroxide solution is used as a desorbent to desorb the germanium-loaded resin, passing the desorbent through the ion exchange column at a flow rate of 2–3 BV, yielding a sodium germanate desorbent with a germanium concentration of 2–8 g / L. The regenerated resin is then reused.
[0041] 2) Germanium enrichment and precipitation: The sodium germanate enrichment solution is pumped into a stirred reactor, and ferric sulfate is slowly added to it. The reaction is carried out at a reaction temperature of 40-70℃ for 0.5-1h until the germanium concentration in the solution is <2mg / L. After the reaction is completed, the reaction slurry is subjected to liquid-solid separation to obtain germanium enrichment with a germanium content of 3-10%.
[0042] (5) Indium recovery: Indium in the germanium recovery solution is recovered using solvent extraction. A suitable operating method is to use a P204-sulfonated kerosene system, with an extraction ratio of O / A of 1:2 to 1:3, a mixing time of 3 to 15 min, and a clarification time of 5 to 30 min. During extraction, indium enters the organic phase, while Fe²⁺, Zn²⁺, Cd²⁺, etc., remain in the aqueous phase. To further reduce impurity entrainment, the loaded organic phase can be washed with a 0.1 to 0.8 mol / L sulfuric acid solution, preferably 0.2 to 0.5 mol / L; the washing ratio of O / A is 3:1 to 10:1, and the number of washing stages is 1 to 3. The washed loaded organic phase is then back-extracted with 3 to 8 mol / L hydrochloric acid, with a back-extraction ratio of O / A of 2:1 to 10:1. The resulting indium-rich back-extraction solution contains In… 3+ The content is 50–100 g / L. Indium in the back-extraction solution is replaced with zinc flakes to obtain sponge indium, which is then melted and cast before entering the electrolytic refining process to obtain high-purity indium.
[0043] To more clearly illustrate the present invention, the following specific embodiments will be described in detail.
[0044] Example 1
[0045] A method for recovering high-arsenic indium-germanium materials includes the following steps:
[0046] (1) Low-temperature arsenic removal: The high-arsenic indium-germanium material containing 15% As, 0.5% Ge, 0.03% In, 20% Pb, 40% Zn, 11% Cd, and 3% Fe is continuously transported into a medium-low temperature closed belt reactor via a belt conveyor. At a medium-low temperature of 400℃, the low-valence arsenic oxides in the high-arsenic indium-germanium material continuously volatilize and enter the flue to be enriched, resulting in crude arsenic trioxide and low-arsenic indium-germanium material containing 0.3% arsenic.
[0047] (2) Enrichment leaching: The low-arsenic indium-germanium material produced in step (1) is mixed with the indium extraction residue and sent to a stirred reactor for enrichment leaching. The reaction temperature is controlled at 50°C and the reaction is carried out for 2 hours. Sulfuric acid solution is continuously added during the process until the indium concentration in the zinc-rich leaching solution is 0.8 mg / L and the germanium concentration is 1.1 mg / L. After the reaction is completed, the reaction slurry is separated into liquid and solid to obtain indium-germanium enriched slag containing 1.5% Ge and 0.09% In and zinc-rich leaching solution. The zinc-rich leaching solution is replaced with zinc powder and electrowinning. Zinc and cadmium are recovered in the form of cathode zinc and sponge cadmium, respectively.
[0048] (3) Controllable acid solubility:
[0049] 1) High-acid controlled leaching in stage I: The indium-germanium enriched slag produced in step (2) is mixed with the leachate from stage II and then fed into a stirred reactor for reaction. The reaction temperature is controlled at 90℃ and the reaction time is 1 h. Sulfuric acid solution is continuously added as needed according to the final acidity of the leachate. During the reaction, liquefied SO2 is continuously introduced into the reactor. After the reaction is completed, liquid-solid separation is performed to obtain Fe. 3 + The leachate and leaching residue of section I with a concentration of 200 mg / L, Ge 2950 mg / L, In 177 mg / L, and H2SO4 80 g / L;
[0050] 2) Stage II Ultra-High Acid Leaching: The Stage I leaching residue is mixed with sulfuric acid solution and then fed into a stirred reactor for reaction. The reaction temperature is controlled at 90℃ and the reaction time is 1 hour. Sulfuric acid solution is continuously added as needed to control the acidity of the leaching solution at the endpoint. After the reaction, liquid-solid separation is performed to obtain Stage II leaching solution and Stage II leaching residue with a sulfuric acid concentration of 120 g / L. The Stage II leaching residue contains 51% lead and can be returned to the lead smelting system to produce lead ingots.
[0051] (4) Germanium recovery:
[0052] 1) Germanium Separation and Enrichment: An ion exchange process involving adsorption-deep washing-alkaline desorption is used to selectively recover germanium from the first-stage leachate. In this embodiment, the operation is as follows: The first-stage leachate is passed through an ion exchange column at a flow rate of 3 BV using a macroporous anion exchange resin, yielding a germanium recovery solution with a residual germanium concentration of 1.5 mg / L and a germanium-loaded resin. The germanium-loaded resin is washed with water, and the washing solution is returned to the enrichment leaching process. A 15% sodium hydroxide solution is used as a desorbent to desorb the germanium-loaded resin, passing the desorbent through the ion exchange column at a flow rate of 3 BV, yielding a sodium germanate desorbent solution with a germanium concentration of 8 g / L. The regenerated resin is then reused.
[0053] 2) Germanium enrichment and precipitation: The sodium germanate enrichment solution was pumped into a stirred reactor, and ferric sulfate was slowly added to it. The reaction was carried out at a reaction temperature of 60℃ for 0.5h. After the reaction was completed, the reaction slurry was subjected to liquid-solid separation to obtain a germanium enriched solution with a residual germanium concentration of 0.9mg / L and a germanium enrichment with a germanium content of 10%; the total germanium recovery rate of the whole process was 93%.
[0054] (5) Indium Recovery: Indium in the germanium recovery solution was recovered using a solvent extraction process. In this embodiment, the operation method was as follows: a P204-sulfonated kerosene system was used, with an extraction ratio of O / A of 1:2, a mixing time of 3 min, and a clarification time of 30 min. The supported organic phase was washed with a 0.1 mol / L sulfuric acid solution; the washing ratio of O / A was 10:1, and the washing stage was 1. The washed supported organic phase was back-extracted with 3 mol / L hydrochloric acid, with a back-extraction ratio of O / A of 10:1. The resulting indium-rich back-extraction solution contained In... 3+ The concentration was 50 g / L. Indium in the back-extraction solution was replaced with zinc flakes to obtain sponge indium, which was then melted and cast before entering the electrolytic refining process to obtain high-purity indium. The overall indium recovery rate for the entire process was 95%.
[0055] Example 2
[0056] A method for recovering high-arsenic indium-germanium materials includes the following steps:
[0057] (1) Low-temperature arsenic removal: The high-arsenic indium-germanium material containing 25% As, 0.01% Ge, 0.2% In, 35% Pb, 15% Zn, 3% Cd, and 1% Fe is continuously transported into a medium-low temperature closed belt reactor via a belt conveyor. At a medium-low temperature of 500℃, the low-valence arsenic oxides in the high-arsenic indium-germanium material continuously volatilize and enter the flue to be enriched, resulting in crude arsenic trioxide and low-arsenic indium-germanium material containing 0.4% arsenic.
[0058] (2) Enrichment leaching: The low-arsenic indium-germanium material produced in step (1) is mixed with the indium extraction residue and sent to a stirred reactor for enrichment leaching. The reaction temperature is controlled at 65 °C and the reaction is carried out for 1.5 h. Sulfuric acid solution is continuously added during the process until the indium concentration in the zinc-rich leaching solution is 1.2 mg / L and the germanium concentration is 1.5 mg / L. After the reaction is completed, the reaction slurry is separated into liquid and solid to obtain indium-germanium enriched slag containing 0.03% Ge and 0.6% In and zinc-rich leaching solution. The zinc-rich leaching solution is replaced with zinc powder and electrowinning. Zinc and cadmium are recovered in the form of cathode zinc and sponge cadmium, respectively.
[0059] (3) Controllable acid solubility:
[0060] 1) High-acid controlled leaching in stage I: The indium-germanium enriched slag produced in step (2) is mixed with the leachate from stage II and then fed into a stirred reactor for reaction. The reaction temperature is controlled at 70℃ and the reaction time is 3h. Liquefied SO2 is continuously introduced into the reactor. After the reaction is completed, liquid-solid separation is performed to obtain Fe. 3+ The leachate and leaching residue of section I with a concentration of 400 mg / L, Ge 58 mg / L, In 1180 mg / L, and H2SO4 of 60 g / L;
[0061] 2) Stage II Ultra-High Acid Leaching: The Stage I leaching residue is mixed with sulfuric acid solution and then fed into a stirred reactor for reaction. The reaction temperature is controlled at 70℃ for 2 hours. Sulfuric acid solution is continuously added as needed based on the final acidity of the leaching solution. After the reaction, liquid-solid separation is performed to obtain Stage II leaching solution and Stage II leaching residue with a sulfuric acid concentration of 160 g / L. The Stage II leaching residue contains 55% lead and can be returned to the lead smelting system to produce lead ingots.
[0062] (4) Germanium recovery:
[0063] 1) Germanium Separation and Enrichment: An ion exchange process involving adsorption-deep washing-alkaline desorption is used to selectively recover germanium from the first-stage leachate. In this embodiment, the operation is as follows: The first-stage leachate is passed through an ion exchange column at a flow rate of 2 BV using macroporous anion exchange resin, yielding a germanium recovery solution with a residual germanium concentration of 1 mg / L and germanium-loaded resin. The germanium-loaded resin is washed with water, and the washing solution is returned to the enrichment leaching process. A 5% sodium hydroxide solution is used as a desorbent to desorb the germanium-loaded resin, passing the desorbent through the ion exchange column at a flow rate of 2 BV, yielding a sodium germanate desorbent solution with a germanium concentration of 2 g / L. The regenerated resin is then reused.
[0064] 2) Germanium enrichment and precipitation: The sodium germanate enrichment solution was pumped into a stirred reactor, and ferric sulfate was slowly added to it. The reaction was carried out at a reaction temperature of 70°C for 0.5 h until almost all the germanium in the solution was precipitated. After the reaction was completed, the reaction slurry was subjected to liquid-solid separation to obtain a germanium-enriched solution with a germanium concentration of 0.9 mg / L and a germanium-enriched product with a germanium content of 3%; the total germanium recovery rate of the whole process was 90%.
[0065] (5) Indium Recovery: Indium in the germanium recovery solution was recovered using a solvent extraction process. In this embodiment, a P204-sulfonated kerosene system was used, with an extraction ratio of O / A of 1:3, a mixing time of 6 min, and a clarification time of 5 min. To further reduce impurity entrainment, the supported organic phase was washed with a 0.8 mol / L sulfuric acid solution; the washing ratio was 3:1, and the washing stage was 2 stages. The washed supported organic phase was back-extracted with 4 mol / L hydrochloric acid, with a back-extraction ratio of O / A of 5:1. The resulting indium-rich back-extraction solution contained In... 3+ The concentration was 62 g / L. Indium in the back-extraction solution was replaced with zinc flakes to obtain sponge indium, which was then melted and cast before entering the electrolytic refining process to obtain high-purity indium. The overall indium recovery rate for the entire process was 96%.
[0066] Example 3
[0067] A method for recovering high-arsenic indium-germanium materials includes the following steps:
[0068] (1) Low-temperature arsenic removal: High-arsenic indium-germanium material containing 5% As, 0.015% Ge, 3% In, 25% Pb, 30% Zn, 15% Cd, and 5% Fe is continuously conveyed into a medium-low temperature closed belt reactor via a belt conveyor. At a medium-low temperature of 300℃, the low-valence arsenic oxides in the high-arsenic indium-germanium material continuously volatilize and enter the flue to be enriched, resulting in crude arsenic trioxide and low-arsenic indium-germanium material containing 0.47% arsenic.
[0069] (2) Enrichment leaching: The low-arsenic indium-germanium material produced in step (1) is mixed with the indium extraction residue and sent to a stirred reactor for enrichment leaching. The reaction temperature is controlled at 80℃ and the reaction is carried out for 1 hour. Sulfuric acid solution is continuously added during the process until the indium concentration in the zinc-rich leaching solution is 1 mg / L and the germanium concentration is 1.2 mg / L. After the reaction is completed, the reaction slurry is separated into liquid and solid to obtain indium-germanium enriched slag containing 0.06% Ge and 12% In and zinc-rich leaching solution. The zinc-rich leaching solution is replaced with zinc powder and electrowinning. Zinc and cadmium are recovered in the form of cathode zinc and sponge cadmium, respectively.
[0070] (3) Controllable acid solubility:
[0071] 1) High-acid controlled leaching in stage I: The indium-germanium enriched slag produced in step (2) is mixed with the leachate from stage II and then fed into a stirred reactor for reaction. The reaction temperature is controlled at 80℃ and the reaction time is 2 h. Liquefied SO2 is continuously introduced into the reactor. After the reaction is completed, liquid-solid separation is performed to obtain Fe. 3+ The leachate and leaching residue of section I with a concentration of 250 mg / L, Ge 115 mg / L, In 23840 mg / L, and H2SO4 of 100 g / L;
[0072] 2) Stage II Ultra-High Acid Leaching: The Stage I leaching residue is mixed with sulfuric acid solution and then fed into a stirred reactor for reaction. The reaction temperature is controlled at 80℃ and the reaction time is 1 hour. Sulfuric acid solution is continuously added as needed based on the final acidity of the leaching solution. After the reaction, liquid-solid separation is performed to obtain Stage II leaching solution and Stage II leaching residue with a sulfuric acid concentration of 200 g / L. The Stage II leaching residue contains 53% lead and can be returned to the lead smelting system to produce lead ingots.
[0073] (4) Germanium recovery:
[0074] 1) Germanium Separation and Enrichment: An ion exchange process involving adsorption-deep washing-alkaline desorption is used to selectively recover germanium from the first-stage leachate. In this embodiment, the operation is as follows: The first-stage leachate is passed through an ion exchange column at a flow rate of 4 BV using a macroporous anion exchange resin, yielding a germanium recovery solution with a residual germanium concentration of 0.7 mg / L and a germanium-loaded resin. The germanium-loaded resin is washed with water, and the washings are returned to the enrichment leaching process. An 8% sodium hydroxide solution is used as a desorbent to desorb the germanium-loaded resin, passing the desorbent through the ion exchange column at a flow rate of 4 BV, yielding a sodium germanate desorbent solution with a germanium concentration of 5 g / L. The regenerated resin is then reused.
[0075] 2) Germanium enrichment and precipitation: The sodium germanate enrichment solution was pumped into a stirred reactor, and ferric sulfate was slowly added to it. The reaction was carried out at 40°C for 1 hour until almost all the germanium in the solution was precipitated. After the reaction was completed, the reaction slurry was separated into liquid and solid, and a germanium-enriched solution with a germanium concentration of 1.2 mg / L and a germanium-enriched product with a germanium content of 4.5% were obtained. The total germanium recovery rate of the whole process was 91.5%.
[0076] (5) Indium Recovery: Indium in the germanium recovery solution is recovered using solvent extraction. The appropriate operating method is to use a P204-sulfonated kerosene system with an extraction ratio of O / A of 1:2, a mixing time of 15 min, and a clarification time of 15 min. The supported organic phase is washed with 0.8 mol / L sulfuric acid solution; the washing ratio is 6:1, and the washing stage is 3 stages. The washed supported organic phase is then back-extracted with 8 mol / L hydrochloric acid, with an extraction ratio of O / A of 2:1. The resulting indium-rich back-extraction solution contains In... 3+ The concentration was 100 g / L. Indium in the back-extraction solution was replaced with zinc flakes to obtain sponge indium, which was then melted and cast before entering the electrolytic refining process to obtain high-purity indium. The overall indium recovery rate for the entire process was 96%.
[0077] Comparative Example 1
[0078] Compared with Example 1, step (2) enrichment leaching was omitted in this comparative example, but everything else was the same as in Example 1.
[0079] A method for recovering high-arsenic indium-germanium materials includes the following steps:
[0080] (1) Low-temperature arsenic removal: The high-arsenic indium-germanium material is subjected to low-temperature arsenic removal to obtain crude arsenic trioxide and low-arsenic indium-germanium material with 0.4% arsenic.
[0081] (2) Controllable acid solubility:
[0082] 1) Stage I high-acid controlled leaching: The low-arsenic indium-germanium material produced in step (1) is mixed with the stage II leaching solution and reacted. After the reaction is completed, liquid-solid separation is performed to obtain Fe. 3+The leachate and leaching residue of section I with a concentration of 1100 mg / L, Ge 730 mg / L, In 45 mg / L, and H2SO4 of 80 g / L;
[0083] 2) Stage II Ultra-High Acid Leaching: The Stage I leaching residue is mixed with sulfuric acid solution and then fed into a stirred reactor for reaction. The reaction temperature is controlled at 70℃ for 2 hours. Sulfuric acid solution is continuously added as needed based on the final acidity of the leaching solution. After the reaction, liquid-solid separation is performed to obtain Stage II leaching solution and Stage II leaching residue with a sulfuric acid concentration of 160 g / L. The Stage II leaching residue contains 46% lead and can be returned to the lead smelting system to produce lead ingots.
[0084] (3) Germanium recovery:
[0085] 1) Germanium separation and enrichment: Sodium germanate desorption solution with a germanium concentration of 0.5 g / L was obtained, and the regenerated resin was reused.
[0086] 2) Germanium enrichment and precipitation: a germanium enrichment solution with a germanium concentration of 0.9 mg / L and a germanium enrichment with a germanium content of 0.7% were obtained; the total germanium recovery rate of the whole process was 60%.
[0087] (4) Indium recovery: In the obtained indium-rich stripping solution 3+ The content was 13 g / L. Indium in the back-extraction solution was replaced with zinc flakes to obtain sponge indium, which was then melted and cast before entering the electrolytic refining process to obtain high-purity indium. The total indium recovery rate of the entire process was 57%.
[0088] It should be noted that the purpose of enrichment leaching in this invention is to dissolve more than 90% of zinc and cadmium in the raw material into the zinc-rich leaching solution, thereby efficiently enriching indium and germanium in the indium-germanium enrichment slag. The high-arsenic indium-germanium material contains 0.01-0.5% Ge and 0.03-3% In. After enrichment leaching, the indium-germanium enrichment slag contains 0.03-1.5% Ge and 0.09-12% In, with an indium-germanium enrichment of more than 3 times. This high-indium-germanium, low-zinc-cadmium enrichment slag can achieve efficient leaching of indium and germanium in the first-stage high-acid controlled leaching, and obtain a first-stage leaching solution with high indium and germanium concentrations. Step (2) enrichment leaching is canceled, and the indium and germanium concentrations in the first-stage leaching solution are reduced from 177 mg / L and 2950 mg / L to 45 mg / L and 730 mg / L, respectively. At the same time, Fe 3+ As the concentration increased from 200 mg / L to 1100 mg / L, the leaching rates of indium and germanium decreased by 25% and 22%, respectively. Low concentrations of indium and germanium, and high concentrations of Fe... 3+ The leaching solution caused a further decrease in the recovery rates of indium and germanium in subsequent germanium and indium recovery processes, resulting in a downgrade in the quality of indium and germanium products. Ultimately, this led to a 33% decrease in the total recovery rate of germanium and a 38% decrease in the total recovery rate of indium throughout the entire process.
[0089] Comparative Example 2
[0090] Compared with Example 1, the high acid leaching in step (3) of this comparative example does not introduce SO2 and does not control ferric iron, but is otherwise the same as Example 1.
[0091] A method for recovering high-arsenic indium-germanium materials includes the following steps:
[0092] (1) Low-temperature arsenic removal: crude arsenic trioxide and low-arsenic indium-germanium material containing 0.3% arsenic were obtained;
[0093] (2) Enrichment leaching: Indium germanium enrichment residue containing 1.5% Ge and 0.09% In and zinc rich leaching solution were obtained. The zinc rich leaching solution was subjected to zinc powder replacement and electrowinning treatment. Zinc and cadmium were recovered in the form of cathode zinc and sponge cadmium, respectively.
[0094] (3) Controllable acid solubility:
[0095] 1) Controlled high-acid leaching in stage I: The indium-germanium enriched slag produced in step (2) is mixed with the leachate from stage II and then fed into a stirred reactor for reaction. The reaction temperature is controlled at 90℃ and the reaction time is 1 h. Sulfuric acid solution is continuously added as needed based on the final acidity of the leachate. After the reaction is completed, liquid-solid separation is performed to obtain Fe. 3+ The leachate and leaching residue of section I with a concentration of 36000 mg / L, Ge 2330 mg / L, In 145 mg / L, and H2SO4 concentration of 80 g / L;
[0096] 2) Stage II ultra-high acid leaching: After the reaction, liquid-solid separation is performed to obtain Stage II leaching solution with a sulfuric acid concentration of 120 g / L and Stage II leaching residue. Stage II leaching residue contains 48% lead and can be returned to the lead smelting system to produce lead ingots.
[0097] (4) Germanium recovery:
[0098] 1) Germanium separation and enrichment: Sodium germanate desorption solution with a germanium concentration of 3.5 g / L was obtained, and the regenerated resin was reused.
[0099] 2) Germanium enrichment and precipitation: a germanium enrichment solution with a residual germanium concentration of 2 mg / L and a germanium enrichment with a germanium content of 4.4% were obtained; the total germanium recovery rate of the whole process was 21%.
[0100] (5) Indium recovery: In the obtained indium-rich stripping solution 3+ The concentration was 36 g / L. Indium in the back-extraction solution was replaced with zinc flakes to obtain sponge indium, which was then melted and cast before entering the electrolytic refining process to obtain high-purity indium. The overall indium recovery rate for the entire process was 55%.
[0101] Note: Unless otherwise specified, all percentage contents mentioned in this invention are mass percentage contents.
[0102] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.
Claims
1. A method for recovering high-arsenic indium-germanium materials, characterized in that: Includes the following steps: (1) Arsenic removal; (2) Enrichment leaching: After the arsenic removal, the indium-germanium-containing material is mixed with acid and sent into a stirred reactor for enrichment leaching. After the reaction is completed, the reaction slurry is separated into liquid and solid to obtain indium-germanium enriched slag and zinc-rich leachate. (3) Controllable acid solubility: 1) Stage I high acid leaching: The indium-germanium enriched slag produced in step (2) is mixed with the leachate from stage II and then fed into a stirred reactor for reaction; the Fe content in the solution is controlled. 3+ < 500 mg / L, after the reaction is completed, liquid-solid separation is performed to obtain the first stage leachate and the first stage leach residue; 2) Stage II ultra-high acid leaching: The leaching residue from Stage I is mixed with sulfuric acid solution and then fed into a stirred reactor for reaction. Concentrated sulfuric acid is added to the reactor. After the reaction is completed, liquid-solid separation is performed to obtain Stage II leachate and Stage II leaching residue. Stage II leachate is returned to Stage I high acid controlled leaching. (4) Germanium recovery: including, 1) Germanium separation and enrichment: Germanium is selectively recovered from the high acid leaching solution in stage I using an ion exchange process to obtain sodium germanate enrichment solution and germanium recovery solution. 2) Germanium enrichment and precipitation: The sodium germanate enrichment solution produced in step 1) is pumped into a stirred reactor, and ferric sulfate is added until the germanium concentration in the solution is <2 mg / L. After the reaction is completed, liquid-solid separation is performed to obtain the germanium enrichment. (5) Indium recovery: Indium is selectively recovered from germanium recovery liquid using solvent extraction process to obtain high indium back-extraction liquid and indium extraction residue.
2. The method for recovering high-arsenic indium-germanium materials according to claim 1, characterized in that: In step (3), the sulfuric acid concentration of the leachate in section I is 10-80 g / L, and the sulfuric acid concentration of the leachate in section II is 120-200 g / L.
3. The method for recovering high-arsenic indium-germanium materials according to claim 2, characterized in that: In step (3), the first stage of high-acid leaching involves introducing liquefied SO2 to control the Fe content in the solution. 3+ < 500 mg / L.
4. The method for recovering high-arsenic indium-germanium materials according to claim 1, characterized in that: In step (4), germanium separation and enrichment adopts an ion exchange process of adsorption-deep washing-alkaline desorption.
5. The method for recovering high-arsenic indium-germanium materials according to any one of claims 1-4, characterized in that: The indium extraction residue from step (5) is returned to step (2).
6. The method for recovering high-arsenic indium-germanium materials according to any one of claims 1-5, characterized in that: The arsenic removal in step (1) is as follows: high-arsenic indium-germanium materials are continuously fed into a medium-low temperature closed belt reactor. At medium-low temperature, the low-valence arsenic oxides in the high-arsenic indium-germanium materials continuously volatilize and enter the flue to enrich, thus obtaining crude arsenic trioxide and low-arsenic indium-germanium materials.
7. A method for recovering high-arsenic indium-germanium materials according to any one of claims 1-6, characterized in that: The low-arsenic indium-germanium material produced in step (1) contains less than 0.5% arsenic.
8. A method for recovering high-arsenic indium-germanium materials according to any one of claims 1-7, characterized in that: The acid solution in step (2) is the indium extraction residue or a mixture of indium extraction residue and sulfuric acid solution. The concentrations of indium and germanium in the zinc-rich leachate produced are both < 2 mg / L. The indium-germanium enrichment residue contains 0.03-1.5% Ge and 0.09-12% In.
9. A method for recovering high-arsenic indium-germanium materials according to any one of claims 1-9, characterized in that: High-arsenic indium-germanium materials are secondary hazardous waste resources produced by high-arsenic indium-germanium neutralization and enrichment slag or indium-germanium hazardous waste slag generated during hydrometallurgical processes through high-temperature reduction and volatilization. The indium-germanium materials contain 5-25% As, 0.01-0.5% Ge, 0.03-3% In, 20-35% Pb, 15-40% Zn, 3-15% Cd, and 1-5% Fe.