Method for recycling germanium from germanium-containing high-concentration waste hydrochloric acid solution

Abstract

The invention belongs to the technical field of resource regeneration, and particularly relates to a method for recycling germanium from a germanium-containing high-concentration waste hydrochloric acid solution, which comprises the following steps: carrying out extraction by using kerosene or sulfonated kerosene, carrying out reverse extraction by using diluted hydrochloric acid or diluted sulfuric acid, and carrying out germanium precipitation enrichment by using calcium hydroxide and polyferric sulfate. According to the method, kerosene or sulfonated kerosene is adopted as an extracting agent to extract the regenerated germanium from the germanium-containing high-concentration waste hydrochloric acid solution; the method has the advantages that the extracting agent is low in price, stable, common, easy to obtain, environmentally friendly, suitable for the germanium-containing high-concentration hydrochloric acid solution with the HCl molar concentration larger than or equal to 8.5 mol / L, capable of synchronously recycling germanium and hydrochloric acid, higher in germanium recovery rate, lower in recovery cost, simpler in process and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of resource recycling, and particularly relates to a method for recycling germanium from a hydrochloric acid solution with a high germanium concentration. Background Art

[0002] Germanium is a rare and dispersed metal with extremely low crustal content and high value. It is also an important semiconductor material and is widely used in the fields of infrared material manufacturing, photovoltaic industry, optical fiber industry, PET catalyst, food and drug production, etc. In high-tech fields such as new energy, infrared optics, optical fibers, catalysts, and electronics and solar energy, the demand for germanium is continuously increasing. However, due to the complex production process of germanium, its direct metal recovery rate is relatively low, and coupled with its high value and scarcity, the comprehensive recovery of germanium in the production process has important economic and environmental protection significance.

[0003] The production of high-purity germanium dioxide involves multiple process steps, including distillation, double distillation, hydrochloric acid extraction and purification, rectification, hydrolysis, washing, and drying, etc. In these processes, due to the certain solubility of germanium tetrachloride and high-purity germanium dioxide in aqueous solution or hydrochloric acid solution, waste hydrochloric acid solutions containing germanium will be generated during the production process. These waste liquids mainly include the following four types:

[0004] 1) Spent absorption acid: The waste liquid generated after germanium tetrachloride gas is absorbed by hydrochloric acid during germanium chlorination distillation, chlorine passing and double distillation, and rectification processes. The germanium concentration in it is 50 - 200 μg / mL, and the hydrochloric acid concentration ≥ 9 mol / L.

[0005] 2) Double-distillation waste acid: During the double-distillation process, crude germanium tetrachloride is mixed with analytical pure hydrochloric acid and then distilled to obtain pure germanium tetrachloride. The remaining hydrochloric acid containing impurities is the double-distillation waste acid or double-distillation residual acid. The germanium concentration in it is 100 - 400 μg / mL, and the hydrochloric acid concentration is 6.5 - 8.5 mol / L.

[0006] 3) Germanium tetrachloride extraction and purification loaded hydrochloric acid: After crude germanium tetrachloride is stirred and purified in hydrochloric acid, impurities enter the hydrochloric acid to form loaded hydrochloric acid. The germanium concentration in it is 100 - 200 μg / mL, and the hydrochloric acid concentration is 10 - 12 mol / L.

[0007] 4) Hydrolysis mother liquor: During the hydrolysis process of high-purity germanium tetrachloride to produce high-purity germanium dioxide and hydrochloric acid, the residual liquid after filtration is the hydrolysis mother liquor. The germanium concentration in it is 1000 - 1500 μg / mL, and the hydrochloric acid concentration is 4.5 - 5.5 mol / L.

[0008] The characteristics of the above waste liquid are high hydrochloric acid concentration, high germanium content, and low heavy metal impurity content. Therefore, it has high recycling value. Currently, in industry, usually after neutralizing the hydrochloric acid in the waste liquid with alkali, the germanium is recovered by tannin precipitation method, zinc replacement method or coprecipitation method. However, these methods have significant disadvantages: 1) The use of a large amount of alkali leads to waste of hydrochloric acid and increases the cost of neutralization treatment; 2) The grade of the recovered germanium concentrate is relatively low (generally the germanium content is less than 5%), resulting in an increase in the subsequent purification cost; 3) The use of reagents such as tannic acid or zinc significantly increases the environmental protection treatment pressure and cost of the recovery system.

[0009] The inventor has developed a method for extracting germanium from hydrochloric acid system with butyl acetate, but this method is only applicable to the range where the molar concentration of HCl is 5.5 - 6.5 mol / L. When the molar concentration of HCl exceeds 6.5 mol / L, the decomposition ratio of butyl acetate increases significantly with the increase of concentration. For example, when the molar concentration of HCl reaches 7 mol / L, the decomposition loss of butyl acetate reaches 5 - 8%; when the concentration rises to 7.5 mol / L or higher, the decomposition loss exceeds 10%. This not only causes excessive loss of the organic phase and increases the industrialization cost, but also causes the hydrochloric acid after extraction to contain organic residues, affecting the performance and reuse value of the regenerated hydrochloric acid. Therefore, butyl acetate is not suitable for the extraction and recovery process of germanium-containing waste hydrochloric acid solution with a molar concentration of HCl exceeding 6.5 mol / L. Summary of the Invention

[0010] Aiming at the above technical deficiencies, the present invention provides a method for resource utilization of germanium from high-concentration germanium-containing waste hydrochloric acid solution, which can extract and regenerate germanium and hydrochloric acid from high-concentration germanium-containing hydrochloric acid solution with a molar concentration of HCl greater than or equal to 8.5 mol / L. This method can regenerate germanium and hydrochloric acid synchronously, and has the advantages of simple process, low cost and high efficiency, more stable structure of the extractant, and higher enrichment ratio of germanium.

[0011] Specifically, a method for resource utilization of germanium from high-concentration germanium-containing waste hydrochloric acid solution includes:

[0012] S1: Using kerosene or sulfonated kerosene as the extraction organic phase (extractant), extracting the germanium-containing waste hydrochloric acid solution, and the germanium enters the organic phase; standing for phase separation; obtaining the germanium-containing organic phase and the aqueous phase; the molar concentration of HCl in the germanium-containing waste hydrochloric acid solution is greater than or equal to 8.5 mol / L;

[0013] S2: Using dilute hydrochloric acid or dilute sulfuric acid as the stripping solution, stripping the germanium-containing organic phase obtained in step S1, and the germanium is enriched in the aqueous phase; standing for phase separation; obtaining the germanium-containing stripping solution (i.e., the aqueous phase);

[0014] S3: Using calcium hydroxide and polyferric sulfate as precipitants, co-capture and precipitate germanium from the germanium-containing stripping solution obtained in step S2; then add sodium hydroxide to adjust the pH to 7-9, and age; after aging, perform solid-liquid separation to obtain a precipitate, which is dried to obtain the regenerated germanium raw material.

[0015] The present invention has found through research that when using kerosene or sulfonated kerosene as the extractant, germanium elements can be effectively extracted in a germanium-containing waste hydrochloric acid solution system with a hydrochloric acid molar concentration greater than or equal to 8.5 mol / L. Kerosene or sulfonated kerosene has a low viscosity and a large density difference from the aqueous phase, and no diluent needs to be added to the extraction organic phase; moreover, when kerosene or sulfonated kerosene is used to extract germanium from a waste hydrochloric acid solution containing high-concentration hydrochloric acid, the phase separation speed is fast and there is no emulsification phenomenon, and no modifier needs to be added to the extraction organic phase.

[0016] In some preferred embodiments, in step S1, the volume ratio of the germanium-containing waste hydrochloric acid solution to the extraction organic phase is (3-30):1, such as 3:1, 5:1, 8:1, 15:1, or 30:1.

[0017] In some preferred embodiments, in step S1, the extraction time is 1-5 min.

[0018] In some preferred embodiments, in step S1, mixing and stirring are performed during the extraction process.

[0019] In some preferred embodiments, in step S1, the standing phase separation time is 5-15 min.

[0020] In some preferred embodiments, in step S1, the germanium-containing waste hydrochloric acid solution is transparent and free of suspended matter.

[0021] In some preferred embodiments, in step S1, the hydrochloric acid molar concentration in the germanium-containing waste hydrochloric acid solution is 8.5-12.5 mol / L, such as 8.5 mol / L, 9.0 mol / L, 9.2 mol / L, 9.5 mol / L, 10 mol / L, 10.5 mol / L, 10.9 mol / L, 11 mol / L, 11.5 mol / L, 12.2 mol / L, or 12.5 mol / L.

[0022] In some preferred embodiments, in step S1, the germanium-containing waste hydrochloric acid solution is any one or a mixture of several of the waste absorption acid, re-evaporated waste acid, hydrochloric acid-loaded germanium tetrachloride extraction and purification, and hydrolysis mother liquor generated during the production of high-purity germanium dioxide, and it is necessary to ensure that the hydrochloric acid molar concentration in the germanium-containing waste hydrochloric acid solution is greater than or equal to 8.5 mol / L. When it is a mixture, it can be mixed in any proportion, and it is necessary to ensure that the hydrochloric acid molar concentration in the germanium-containing waste hydrochloric acid solution is greater than or equal to 8.5 mol / L.

[0023] In some preferred embodiments, the germanium-containing waste hydrochloric acid solution is a mixture of waste absorption acid, re-evaporated waste acid, hydrochloric acid-loaded germanium tetrachloride extraction and purification, and hydrolysis mother liquor produced during the production of high-purity germanium dioxide in any proportion; the molar concentration of HCl must be greater than or equal to 8.5 mol / L.

[0024] During the extraction process of step S1, germanium in the germanium-containing waste hydrochloric acid solution enters the organic phase. The aqueous phase is pure hydrochloric acid solution with very low metal impurity content, which can be recycled to the germanium production line or used for the production of gallium and indium, etc.

[0025] During the extraction of the germanium-containing waste hydrochloric acid solution, when the molar concentration of HCl in the solution is greater than or equal to 8.5 mol / L, kerosene or sulfonated kerosene has a high extraction rate for germanium. The structure of kerosene or sulfonated kerosene is very stable. Even when the molar concentration of HCl in the solution is greater than 10 mol / L, even up to 12 mol / L or more, the decomposition or loss of the organic phase is still very little; when the molar concentration of HCl in the solution is less than 8.5 mol / L, the extraction rate of kerosene or sulfonated kerosene for germanium will decrease with the decrease of the molar concentration of HCl in the aqueous phase. After mixing the four germanium-containing waste hydrochloric acid solutions of waste absorption acid, re-evaporated waste acid, hydrochloric acid-loaded germanium tetrachloride extraction and purification, and hydrolysis mother liquor produced during the production of high-purity germanium dioxide in any proportion, the molar concentration of HCl in the solution must be greater than or equal to 8.5 mol / L, which is exactly within the preferred condition range for germanium extraction by kerosene or sulfonated kerosene.

[0026] Through the extraction and separation in step S1 of the present invention, while selectively and fully extracting germanium in the germanium-containing waste hydrochloric acid solution into the organic phase, the molar concentration of HCl in the aqueous phase after extraction and separation is greater than or equal to 8.3 mol / L, which can be recycled to the germanium production line or used for the production of gallium and indium, etc.

[0027] In step S2 stripping of the present invention, by using the characteristic that germanium enters the organic phase at high hydrochloric acid concentration and enters the aqueous phase at low hydrochloric acid concentration or zero hydrochloric acid concentration, when controlling the stripping solution to be at low hydrochloric acid concentration or zero hydrochloric acid concentration and in a small volume, germanium can be stripped into dilute hydrochloric acid or dilute sulfuric acid solution and effectively enriched. The enrichment ratio of germanium in the stripping solution relative to the germanium-containing waste hydrochloric acid solution is greater than or equal to 6 times, and can reach up to hundreds of times at most.

[0028] During the stripping in step S2, germanium in the germanium-containing organic phase enters the stripping solution (i.e., dilute hydrochloric acid or dilute sulfuric acid), and germanium is enriched in the aqueous phase; the organic phase is also regenerated and can be recycled to step 1) for use.

[0029] In some preferred embodiments, when stripping in step S2, the molar concentration of the dilute hydrochloric acid used must be controlled at 0.1 - 0.8 mol / L, or the molar concentration of the dilute sulfuric acid used during stripping must be controlled at 0.1 - 0.4 mol / L.

[0030] In some preferred embodiments, the volume ratio of the germanium-containing organic phase to the stripping solution in step S2 is (2-20):1, for example, 2:1, 3:1, 6:1, 8:1, 10:1, 15:1 or 20:1.

[0031] In some preferred embodiments, the stripping time in step S2 is 3-15 min.

[0032] In some preferred embodiments, mixing and stirring are performed during the extraction process in step S2.

[0033] In some preferred embodiments, the time for standing and separating the phases in step S2 is 5-20 minutes.

[0034] Step S3 adds calcium hydroxide and a combined collector of polyferric sulfate and germanium to the germanium-containing stripping solution, and neutralizes the solution with sodium hydroxide and caustic soda to adjust the pH to 7-9, and utilizes the property that the germanate of heavy metals and alkaline earth metals is insoluble in water to generate iron germanate and calcium germanate precipitates from iron and calcium in the solution; if dilute sulfuric acid is selected as the stripping solution in step S2, part of the calcium will also produce calcium sulfate precipitates; polyferric sulfate itself is a high-performance inorganic polymer coagulant, which coagulates other precipitates and then adsorbs germanium to form a copolymerized precipitate. After drying, the germanium-rich precipitate meets the requirements of the three-level combined state regenerated germanium raw material in GB / T23522 "Regenerated Germanium Raw Materials" and can be sold directly.

[0035] In some preferred embodiments, the total mass of calcium hydroxide and polyferric sulfate added in step S3 is 4-8 times (e.g., 4, 5, 6, 7 or 8 times) the total mass of germanium in the germanium-containing waste hydrochloric acid solution; the mass ratio of the added calcium hydroxide and polyferric sulfate is 1:(2-5), for example, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5.

[0036] In some preferred embodiments, the aging time in step S3 is greater than or equal to 60 min (eg, 60-120 min).

[0037] In some preferred embodiments, the drying temperature in step S3 is 150-250° C., and the drying time is greater than or equal to 10 hours.

[0038] The mechanism of germanium precipitation in the present invention is as follows: After a small amount of free HCl or H2SO4 in the stripping solution is neutralized with sodium hydroxide, the pH value is adjusted to 7-9. During the pH rise process, germanium is first generated in the form of GeO2 or weakly dissociated H2GeO3, and then the GeO2 in the solution is converted into Na2GeO3, which is easily soluble in water, to generate GeO3 2－ ions, as shown in reaction equations (1) and (2).

[0039] Using a mixture of calcium hydroxide and polyferric sulfate as a composite germanium precipitation agent, taking advantage of the property that germanates of heavy metals and alkaline earth metals are insoluble in water, iron and calcium in the solution form iron germanate and calcium germanate precipitates; if dilute sulfuric acid is selected as the stripping solution in step S2, some calcium will also form calcium sulfate precipitate; polyferric sulfate itself is a high-performance inorganic polymer coagulant, which coagulates with other precipitates and jointly adsorbs germanium to form a coprecipitation, obtaining a germanium concentrate with a germanium grade greater than 10%. Some examples of the reaction equations are as follows:

[0040] If polyferric sulfate is added to the stripping solution and the final pH value of the solution is adjusted to 7 - 9, Fe 3+ will hydrolyze to form Fe(OH)3 precipitate when the pH value is greater than 1.6, and the hydrolysis is complete when the pH value is greater than 5.2. The hydrolysis reaction is shown in reaction equation (3), and the Fe(OH)3 precipitate and other iron precipitate polymers have a strong adsorption capacity for Ge. Subsequently, germanium is adsorbed and the coprecipitation process is completed through gravity.

[0041] In addition, Fe 3+ reacting with GeO3 2－ can also obtain insoluble Fe2(GeO3)3 precipitate, thereby precipitating and enriching germanium in the solution in the form of iron germanate, as shown in detail in equation (4).

[0042] If calcium hydroxide is added to the stripping solution, calcium reacts with sulfate ions to form calcium sulfate precipitate, as shown in reaction equation (5). It has a strong adsorption capacity for Ge together with the iron precipitate polymer. Subsequently, germanium is adsorbed and the coprecipitation process is completed through gravity.

[0043] In addition, by adjusting the final pH value of the solution to 7 - 9, Ca 2+ reacting with GeO3 2－ obtains insoluble CaGeO3 precipitate, thereby precipitating and enriching germanium in the solution in the form of calcium germanate, as shown in detail in equation (6).

[0044] GeO2 + 2NaOH = Na2GeO3 + H2O (1)

[0045] H2GeO3 + 2NaOH = Na2GeO3 + 2H2O (2)

[0046] Fe 3+ + 3NaOH = 3Na + + Fe(OH)3↓ (3)

[0047] 3Na2GeO3 + 2Fe 3+ = 6Na + + Fe2(GeO3)3↓ (4)

[0048] Ca2+ +SO4 2- = CaSO4↓ (5)

[0049] Na2GeO3 + CaCl2 = 2NaCl + CaGeO3↓ (6)

[0050] Through the extraction separation and stripping process, the present invention effectively separates germanium from hydrochloric acid solution, realizing the enrichment of germanium and the regeneration of hydrochloric acid. Germanium is enriched in the stripping solution. In the germanium production process, germanium-containing materials usually need to be converted into germanium tetrachloride through chlorination distillation. However, if the germanium-containing stripping solution is directly subjected to chlorination distillation, the moisture in it will dilute the molar concentration of HCl in hydrochloric acid. To ensure the distillation yield of germanium, a high molar concentration of HCl in the solution needs to be maintained, thus increasing the consumption of hydrochloric acid. The present invention adopts a process of neutralizing the germanium-containing stripping solution and then further enriching germanium using a germanium precipitation agent. On the one hand, this method can significantly improve the enrichment degree of germanium and obtain a higher-grade germanium concentrate; on the other hand, in the subsequent germanium chlorination distillation process, the consumption of hydrochloric acid can be significantly reduced, the production cost can be lowered, and the production efficiency of germanium can be improved at the same time. This process optimizes the recovery and utilization of germanium and provides a more economical and efficient solution for the industrial production of germanium.

[0051] Beneficial Effects

[0052] The method of the present invention uses kerosene or sulfonated kerosene as a germanium extractant to regenerate germanium and hydrochloric acid from germanium-containing hydrochloric acid solution. While fully resource-utilizing germanium and hydrochloric acid, it significantly improves the recovery rate of germanium and reduces the regeneration cost of germanium and hydrochloric acid. The advantages of using the above method are as follows: the extraction rate and stripping rate of the extractant for germanium are both as high as over 98%; the enrichment ratio of germanium in the whole process from germanium-containing solution to germanium concentrate is as high as hundreds of times; kerosene or sulfonated kerosene has a stable structure, low price and is easy to obtain, and there is basically no loss during the extraction and stripping processes; both germanium and hydrochloric acid are fully regenerated, the whole process is environmentally friendly, and waste minimization is achieved; the regeneration process is short, the process is simple, the cost is low, the direct recovery rate of germanium is greater than 96%, and the direct recovery rate of hydrochloric acid is greater than 98%. Description of the Drawings

[0053] Figure 1 It is a schematic flow chart of the method for resource-utilizing germanium in a germanium-containing high-concentration waste hydrochloric acid solution in an embodiment of the present invention. Detailed Embodiments

[0054] To make the above objects, features and advantages of the present invention more obvious and understandable, the detailed embodiments of the present invention will be described below. Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0055] For the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each intermediate value within any stated value or stated range, as well as each smaller range between any other stated value or intermediate value within the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded from the range.

[0056] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention pertains. Although the present invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In case of conflict with any incorporated document, the content of this specification shall prevail.

[0057] Without departing from the scope or spirit of the present invention, various improvements and changes can be made to the specific embodiments of the description of the present invention, which are obvious to those skilled in the art. Other embodiments obtained from the description of the present invention are obvious to those skilled in the art. The description and examples of this application are merely exemplary.

[0058] Regarding the use of "comprising", "including", "having", "containing", etc. herein, they are all open-ended terms, meaning including but not limited to.

[0059] The technical solutions described in the present invention, unless otherwise specified, are all conventional solutions in the art, and the reagents or raw materials used, unless otherwise specified, are all purchased from commercial channels or are already publicly available.

[0060] The schematic flow diagram of the method for resource recovery of germanium from high-concentration germanium-containing waste hydrochloric acid solution in the following examples is shown in Figure 1 。

[0061] Example 1

[0062] A method for resource recovery of germanium from high-concentration germanium-containing waste hydrochloric acid solution, comprising:

[0063] S1: Using sulfonated kerosene as the extraction organic phase, extracting the germanium-containing waste hydrochloric acid solution, and germanium enters the organic phase; standing for phase separation; obtaining a germanium-containing organic phase and an aqueous phase;

[0064] The volume ratio of the germanium-containing waste hydrochloric acid solution to the extraction organic phase is 5:1; the extraction time is 5 min; the standing time is 12 min; the germanium-containing waste hydrochloric acid solution is a mixture of waste absorption acid, double-evaporated waste acid, hydrochloric acid-loaded germanium tetrachloride extraction and purification, and hydrolysis mother liquor generated during the production of high-purity germanium dioxide in a certain factory, with a volume ratio of 20:50:20:10, and the molar concentration of HCL is 9.2 mol / L.

[0065] S2: Using a dilute sulfuric acid solution with a molar concentration of 0.1 mol / L as the stripping solution, stripping the germanium-containing organic phase obtained in step S1, and germanium is enriched in the aqueous phase; standing for phase separation; obtaining a germanium-containing stripping solution; the volume ratio of the germanium-containing organic phase to the stripping solution is 3:1; the stripping time is 9 min; the standing time is 15 min.

[0066] S3: First, add calcium hydroxide and polyferric sulfate to the germanium-containing stripping solution obtained in step 2) to jointly capture and precipitate germanium; then add sodium hydroxide to adjust the pH to 8 and age for 240 min; after aging, perform solid-liquid separation to obtain a precipitate, which is dried (200 °C, 12 h) to obtain the regenerated germanium raw material. Among them, the total mass of calcium hydroxide and polyferric sulfate added is 7 times the total mass of germanium in the germanium-containing waste hydrochloric acid solution; the mass ratio of calcium hydroxide to polyferric sulfate is 1:3.

[0067] Using the method of this example, the direct recovery rate of germanium is finally 98.3%.

[0068] Example 2

[0069] A method for recycling germanium from a germanium-containing high-concentration waste hydrochloric acid solution, including:

[0070] S1: Using sulfonated kerosene as the extraction organic phase, extracting the germanium-containing waste hydrochloric acid solution, and germanium enters the organic phase; standing for phase separation; obtaining a germanium-containing organic phase and an aqueous phase;

[0071] The volume ratio of the germanium-containing waste hydrochloric acid solution to the extraction organic phase is 15:1; the extraction time is 3 min; the standing time is 8 min; the germanium-containing waste hydrochloric acid solution is a mixture of waste absorption acid and hydrochloric acid-loaded germanium tetrachloride extraction and purification generated during the production of high-purity germanium dioxide in a certain factory, with a volume ratio of 80:20, and the molar concentration of HCL is 12.2 mol / L.

[0072] S2: Using a dilute hydrochloric acid solution with a molar concentration of 0.4 mol / L as the stripping solution, stripping the germanium-containing organic phase obtained in step S1, and germanium is enriched in the aqueous phase; standing for phase separation; obtaining a germanium-containing stripping solution; the volume ratio of the germanium-containing organic phase to the stripping solution is 10:1; the stripping time is 5 min; the standing time is 10 min.

[0073] S3: First, add calcium hydroxide and polyferric sulfate to the germanium-containing stripping solution obtained in step 2) to jointly capture and precipitate germanium; then add sodium hydroxide to adjust the pH to 8.5 and age for 120 min; after aging, perform solid-liquid separation to obtain a precipitate, which is dried (160 °C, 15 h) to obtain the regenerated germanium raw material. Among them, the total mass of calcium hydroxide and polyferric sulfate added is 5 times the total mass of germanium in the germanium-containing waste hydrochloric acid solution; the mass ratio of calcium hydroxide to polyferric sulfate is 1:3.

[0074] Using the extraction method of this example, the direct recovery rate of germanium is finally 98.2%.

[0075] Example 3

[0076] A method for recycling germanium from a germanium-containing high-concentration waste hydrochloric acid solution, including:

[0077] S1: Use kerosene as the extraction organic phase to extract the germanium-containing waste hydrochloric acid solution, and germanium enters the organic phase; let it stand for phase separation; obtain a germanium-containing organic phase and an aqueous phase;

[0078] The volume ratio of the germanium-containing waste hydrochloric acid solution to the extraction organic phase is 8:1; the extraction time is 4 min; the standing time is 15 min; the germanium-containing waste hydrochloric acid solution is a mixture of waste absorption acid, re-evaporation waste acid, hydrochloric acid-loaded germanium tetrachloride extraction and purification, and hydrolysis mother liquor with a volume ratio of 50:10:30:10 generated during the production of high-purity germanium dioxide in a certain factory, and the molar concentration of HCL in it is 10.9 mol / L.

[0079] S2: Use a dilute hydrochloric acid solution with a molar concentration of 0.3 mol / L as the stripping solution to strip the germanium-containing organic phase obtained in step S1, and germanium is enriched in the aqueous phase; let it stand for phase separation; obtain a germanium-containing stripping solution; the volume ratio of the germanium-containing organic phase to the stripping solution is 6:1; the stripping time is 85 min; the standing time is 20 min.

[0080] S3: First, add calcium hydroxide and polyferric sulfate to the germanium-containing stripping solution obtained in step 2) to jointly capture and precipitate germanium; then add sodium hydroxide to adjust the pH to 8 and age for 240 min; after aging, perform solid-liquid separation to obtain a precipitate, which is dried (180 °C, 12 h) to obtain the regenerated germanium raw material. Among them, the total mass of calcium hydroxide and polyferric sulfate added is 7 times the total mass of germanium in the germanium-containing waste hydrochloric acid solution; the mass ratio of calcium hydroxide to polyferric sulfate is 1:2.5.

[0081] Using the method of this example, the direct recovery rate of germanium is finally 96.9%.

[0082] Example 4

[0083] The difference from Example 1 is only that: the germanium-containing waste hydrochloric acid solution is the waste absorption acid generated during the production of high-purity germanium dioxide in a certain factory, and the molar concentration of HCL in it is 9.0 mol / L.

[0084] Using the method of this example, the direct recovery rate of germanium is 97.8%.

[0085] Example 5

[0086] The difference from Example 1 is only that: the germanium-containing waste hydrochloric acid solution is the re-evaporated waste acid generated during the production of high-purity germanium dioxide in a certain factory, and the molar concentration of HCL in it is 8.5 mol / L.

[0087] Using the method of this example, the direct recovery rate of germanium is 96.7%.

[0088] Comparative Example 1

[0089] The difference from Example 1 is only that: the germanium-containing waste hydrochloric acid solution is the re-evaporated waste acid generated during the production of high-purity germanium dioxide in a certain factory, and the molar concentration of HCL in it is 8.0 mol / L.

[0090] Using the method of this comparative example, the direct recovery rate of germanium is 81.9%.

[0091] Comparative Example 2

[0092] The difference from Example 1 is only that: in step 3) for germanium precipitation and enrichment, only calcium hydroxide is added to the germanium-containing stripping solution for capturing and precipitating germanium.

[0093] Using the method of this comparative example, the direct recovery rate of germanium is 69.3%.

[0094] Comparative Example 3

[0095] The difference from Example 1 is only that: in step 3) for germanium precipitation and enrichment, only polyferric sulfate is added to the germanium-containing stripping solution for capturing and precipitating germanium.

[0096] Using the method of this comparative example, the direct recovery rate of germanium is 91.2%.

[0097] Comparative Example 4

[0098] The difference from Example 1 is only that: the germanium-containing waste hydrochloric acid solution is the waste absorption acid generated during the production of high-purity germanium dioxide in a certain factory, where the molar concentration of HCL is 9.0 mol / L: in step 1), the extraction organic phase is butyl acetate.

[0099] Using the method of this comparative example, the direct recovery rate of germanium is 76.3%, and the loss rate of butyl acetate is 28.6%, making it impossible to achieve industrial application.

[0100] Comparative Example 5

[0101] The difference from Example 1 is only that: the germanium-containing waste hydrochloric acid solution is the residual acid after double evaporation generated during the production of high-purity germanium dioxide in a certain factory, and the molar concentration of HCL in it is 7 mol / L; the extraction organic phase in step 1) is butyl acetate.

[0102] For the method of this comparative example, the direct recovery rate of germanium is 85.6%, and the loss rate of butyl acetate is 7.7%, so it cannot be applied industrially.

[0103] Although the present invention has been described in detail above with general descriptions, specific embodiments and experiments, some modifications or improvements can be made based on the present invention, which are obvious to those skilled in the art. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection required by the present invention.

Claims

1. A method for recycling germanium from high-concentration waste hydrochloric acid solution containing germanium, characterized in that: include: S1: Using kerosene or sulfonated kerosene as the extraction organic phase, extracting the germanium-containing waste hydrochloric acid solution, and the germanium enters the organic phase; Allow to stand for phase separation; Obtaining a germanium-containing organic phase and an aqueous phase; wherein the molar concentration of HCl in the germanium-containing waste hydrochloric acid solution is greater than or equal to 8.5 mol / L; S2: stripping the germanium-containing organic phase obtained in step S1 with dilute hydrochloric acid or dilute sulfuric acid as stripping solution, so that germanium is enriched in the aqueous phase; standing the phases to separate; and obtaining a stripping solution containing germanium; S3: Using calcium hydroxide and polyferric sulfate as precipitants, the germanium-containing stripping solution obtained in step S2 is subjected to combined capture and precipitation of germanium; sodium hydroxide is then added to adjust the pH to 7-9, and the solution is aged; after aging, solid-liquid separation is performed to obtain a precipitate, which is dried to obtain a regenerated germanium raw material.

2. The method for recycling germanium from waste hydrochloric acid solution containing high concentration of germanium according to claim 1, characterized in that: In step S1, the volume ratio of the germanium-containing waste hydrochloric acid solution to the extracted organic phase is (3-30):1, for example, 3:1, 5:1, 8:1, 15:1 or 30:

1.

3. The method for recycling germanium from a high-concentration waste hydrochloric acid solution containing germanium according to claim 1 or 2, characterized in that: In step S1, the extraction time is 1-5 min; and / or, In step S1, mixing and stirring are performed during the extraction process; and / or, In step S1, the standing time for phase separation is 5-15 minutes.

4. The method for recycling germanium from a high-concentration waste hydrochloric acid solution containing germanium according to any one of claims 1 to 3, characterized in that: In step S1, the molar concentration of HCl in the germanium-containing waste hydrochloric acid solution is 8.5-12.5 mol / L, for example, 8.5 mol / L, 9.0 mol / L, 9.2 mol / L, 9.5 mol / L, 10 mol / L, 10.5 mol / L, 10.9 mol / L, 11 mol / L, 11.5 mol / L, 12.2 mol / L or 12.5 mol / L.

5. The method for recycling germanium from waste hydrochloric acid solution containing high concentration of germanium according to any one of claims 1 to 4, characterized in that: In step S1, the germanium-containing waste hydrochloric acid solution is any one or a mixture of waste absorption acid, double-distilled waste acid, germanium tetrachloride extraction and purification loaded hydrochloric acid and hydrolysis mother liquor generated in the production process of high-purity germanium dioxide.

6. The method for recycling germanium from high-concentration waste hydrochloric acid solution containing germanium according to any one of claims 1 to 5, characterized in that: The molar concentration of the dilute hydrochloric acid used in the back extraction in step S2 is 0.1-0.8 mol / L or the molar concentration of the dilute sulfuric acid used in the back extraction is 0.1-0.4 mol / L.

7. The method for recycling germanium from high-concentration waste hydrochloric acid solution containing germanium according to any one of claims 1 to 6, characterized in that: In step S2, the volume ratio of the germanium-containing organic phase to the stripping solution is (2-20):1, for example, 2:1, 3:1, 6:1, 8:1, 10:1, 15:1 or 20:

1.

8. The method for recycling germanium from high-concentration waste hydrochloric acid solution containing germanium according to any one of claims 1 to 7, characterized in that: The stripping time in step S2 is 3-15 min; and / or, In step S2, mixing and stirring are performed during the extraction process; and / or, The time for standing and separating the phases in step S2 is 5-20 minutes.

9. The method for recycling germanium from high-concentration waste hydrochloric acid solution containing germanium according to any one of claims 1 to 8, characterized in that: The total mass of calcium hydroxide and polyferric sulfate added in step S3 is 4-8 times the total mass of germanium in the germanium-containing waste hydrochloric acid solution; the mass ratio of the added calcium hydroxide and polyferric sulfate is 1:(2-5).

10. The method for recycling germanium from waste hydrochloric acid solution containing high concentration of germanium according to any one of claims 1 to 9, characterized in that: The aging time in step S3 is greater than or equal to 60 minutes; and / or, The drying temperature in step S3 is 150-250° C., and the drying time is greater than or equal to 10 hours.

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