Method for preparing metal gallium and germanium concentrate through synergistic extraction

Abstract

The invention relates to a method for preparing metal gallium and germanium concentrate through synergistic extraction. The method comprises the following steps: S1, carrying out liquid-liquid extraction I on the high-acid leaching solution containing gallium and germanium by using a compound organic phase; the compound organic phase comprises substances with structures as shown in a formula (1), a formula (21), a formula (22) and a formula (3); s2, the loaded organic phase obtained in the S1 is subjected to reverse extraction I with a solution of a formula (4), and reverse extraction liquid I containing gallium and iron is obtained; s3, S31, carrying out reverse extraction II on the loaded organic phase obtained by reverse extraction I in S2 by using a solution of a formula (5) to obtain reverse extraction liquid II of germanium; s32, liquid ammonia is introduced into the germanium strip liquor II in the step S31, a reaction is conducted to the end point, a germanium enriched product II is obtained through filtering, and germanium concentrate is obtained after drying and calcination; s4, S41, adding an ion precipitator of a formula (6) into the reverse extraction liquid I containing gallium and iron obtained in the step S2, and filtering to obtain an enriched product I of gallium and iron; and S42, adding a sodium hydroxide solution into the enriched product I of the gallium and the iron in the step S41, filtering, enriching filtrate, and carrying out electrodeposition to prepare the metal gallium.

Description

Technical Field

[0001] The invention relates to the field of recovery of scattered gallium metal, and in particular to a method for preparing metallic gallium and germanium concentrate by synergistic extraction. Background Art

[0002] At present, gallium and germanium are important rare metals. 90% of metallic gallium comes from aluminum smelting, and the rest comes from zinc smelting and coal. The recovery of germanium mainly comes from zinc smelting and coal, each accounting for about 50%.

[0003] In order to obtain a higher gallium-germanium leaching rate from the enriched slag rich in gallium and germanium obtained during zinc smelting, high acid leaching is required. The separation, enrichment and extraction of gallium and germanium from the high acid leaching solution containing gallium and germanium is the most critical core technology. At present, the main process routes for recovering gallium and germanium from the high acid leaching solution containing gallium and germanium are: (1) tannin precipitation of germanium-acetamide extraction of gallium; (2) P204+YW100 synergistic extraction of gallium and germanium; (3) hematite-tertiary carbon carboxylic acid extraction of gallium; (4) chlorinated distillation of germanium-ether extraction of gallium; (5) chlorinated distillation of germanium-TBP extraction of gallium; (6) LIX63 high acid extraction of germanium-low acid phosphate extraction of gallium.

[0004] Although the above-mentioned various process routes can achieve the separation and enrichment of gallium and germanium, these processes still have many disadvantages: (1) Tannin precipitation of germanium and chlorination distillation extraction of germanium have a great impact on the zinc smelting process, and the tannin price is high and the production cost is high; (2) When P204+YW100 is used for synergistic extraction, the gallium extraction rate is low under high acid conditions, and an acid adjustment process is required first. The acid adjustment process not only consumes a large amount of neutralizing agent, but also makes the acid in the leachate unable to be recycled. In addition, YW100 is highly water-soluble and needs to be continuously replenished. The soluble organic matter has a great impact on the zinc smelting process. The impact is large and the cost is high; (3) Before the extraction of tertiary carbon carboxylic acids, an iron reduction process is required, which consumes a large amount of reducing agent. At the same time, the conditions are difficult to control and difficult to apply industrially; (4) Chlorine distillation to extract germanium and extraction to extract gallium both involve chlorine-containing solutions. A large amount of chloride ions are harmful to the zinc smelting process. At the same time, the equipment is severely corroded and the operating environment is poor; (5) LIX63 extracts germanium under high acid conditions, and the extractant degrades quickly. The cost of the extractant is high and it is difficult to purchase domestically. Chloride ions need to be added when extracting gallium, making it difficult to return the raffinate to the zinc system. In summary, the existing processes for extracting and recovering gallium and germanium from high-acid gallium-germanium leaching solutions generally have high production costs and introduce a large amount of harmful chloride ions or organic matter, which limits their application in zinc smelting systems. Summary of the invention

[0005] Based on this, the purpose of the present invention is to solve the shortcomings and deficiencies of the above-mentioned prior art and provide a method for preparing metallic gallium and germanium concentrate by synergistic extraction from a high-acid leaching solution containing gallium and germanium. The method realizes one-step gallium-germanium extraction, step-by-step stripping separation and enrichment of gallium and germanium, does not introduce chlorine-containing harmful impurities, has a simple process method, low production cost, and has wide industrial application value.

[0006] A method for preparing metallic gallium and germanium concentrate by synergistic extraction comprises the following steps:

[0007] Step S1: subjecting the high-acid leaching solution containing gallium and germanium to liquid-liquid extraction I using a composite organic phase; the composite organic phase comprises the following components: 2 vol% to 30 vol% of a hydroxime chelating extractant of formula (1), 20 vol% to 30 vol% of an alkylphenoxy phosphate extractant, 5 vol% to 10 vol% of an alcohol modifier of formula (3), and the remainder being a kerosene diluent; wherein:

[0008] Formula (1):

[0009]

[0010] Wherein, R1 is one of C9-C18 alkyl groups;

[0011] The alkylphenoxy phosphate extractant comprises 88-90 mol% of a monophosphate of formula (21) and 12-10 mol% of a diphosphate of formula (22);

[0012] Formula (21):

[0013]

[0014] Formula (22):

[0015]

[0016] Wherein, in formula (21) and formula (22), R2 is one of C8-C12 alkyl groups;

[0017] Formula (3):

[0018]

[0019] Step S2: stripping the loaded organic phase obtained by liquid-liquid extraction I in step S1 with a solution of formula (4) to obtain a stripping solution I of the loaded organic phase and gallium and iron;

[0020] Formula (4):

[0021]

[0022] Among them, M4 is H +、Na + , K + NH4 + One of;

[0023] Step S3 includes:

[0024] Step S31: The loaded organic phase obtained by stripping I in step S2 is stripped II using a solution of formula (5) to obtain a stripping solution II of germanium;

[0025] Formula (5):

[0026]

[0027] Among them, M5 is NH4 + ;

[0028] Step S32: introducing liquid ammonia into the germanium stripping solution II obtained in step S3, reacting and neutralizing to an end point pH value of 8.5 to 10, filtering to obtain a germanium enriched product II, and drying and calcining the germanium enriched product II to obtain a germanium concentrate;

[0029] Step S4 includes:

[0030] Step S41: adding an ion precipitant of formula (6) to the stripping solution I containing gallium and iron obtained in step S2, and filtering to obtain a gallium and iron enriched product I;

[0031] Formula (6):

[0032]

[0033] Among them, M3 is HH + 、Na + , K + NH4 + One of;

[0034] Step S42: adding sodium hydroxide solution to the gallium and iron enriched product I obtained in step S4, filtering, measuring the gallium concentration in the filtrate or cyclically enriching until the gallium concentration is 20 to 80 g / L and then electrolyzing to prepare metallic gallium.

[0035] The present invention discloses a method for preparing metallic gallium and germanium concentrate by synergistic extraction. The method comprises the following steps: S1, subjecting an acid leaching solution containing high levels of gallium and germanium to liquid-liquid extraction I using a composite organic phase comprising 2 vol% to 30 vol% of a hydroxyoxime chelating extractant having a structure of formula (1), 20 vol% to 30 vol% of a mixed alkylphenoxy phosphate extractant having a structure of 88-90 mol% of a monophosphate having a structure of formula (21) and 12-10 mol% of a bisphosphonate having a structure of formula (22), and 5 vol% to 10 vol% of an alcohol modifier having a structure of formula (3), so that gallium and germanium in the acid leaching solution containing high levels of gallium and germanium are enriched in the loaded organic phase in one step through the liquid-liquid extraction I. Then, gallium and germanium are extracted and separated from the loaded organic phase by step-by-step stripping: first, the loaded organic phase after the liquid-liquid extraction I in step S1 is stripped I using a solution containing a substance having a structure of formula (4) in step S2 to obtain a stripping solution I of gallium and iron, and germanium is left in the loaded organic phase obtained after stripping I, thereby achieving separation of gallium and germanium.

[0036] In step S3, in step S31, the loaded organic phase obtained after stripping I in step S2 is stripped with a solution containing a substance of formula (5) to obtain a stripping solution II of germanium. In step S32, liquid ammonia is introduced into the stripping solution II of germanium obtained in step S31 to obtain a germanium enrichment II, and the germanium enrichment II is dried and calcined to obtain a germanium concentrate.

[0037] In step S4, in step S41, an ion precipitation agent having the structure of formula (6) is added to the stripping solution I obtained after stripping I of gallium and iron in step S2, so that gallium and iron are precipitated, and the gallium and iron enrichment I is obtained by filtering. In step S6, a high-concentration sodium hydroxide solution is added to the gallium and iron enrichment I to precipitate gallium and iron in the gallium and iron enrichment I, and the generated gallium hydroxide is dissolved and filtered to obtain a sodium gallate solution and iron slag, and the gallium concentration in the sodium gallate solution is measured, or a high-concentration sodium gallate solution is obtained by cyclic enrichment and then electrolytically preparing metallic gallium.

[0038] The method for preparing metallic gallium and germanium concentrate by synergistic extraction of the present invention realizes the extraction, separation and enrichment of gallium and germanium from high-acid leaching solution through one-step extraction and step-by-step stripping, and the extraction rate of gallium and germanium is greater than 98%. The method for preparing metallic gallium and germanium concentrate by synergistic extraction of the present invention has the advantages of simple and efficient process flow and high metal recovery rate of the product.

[0039] Furthermore, in step S1, the high-acid leaching solution containing gallium and germanium contains 0.1-3 g / L of gallium and 0.1-3 g / L of germanium, and the main impurities include Fe, Cu, Zn, Sb, As, Co and Ni, wherein the Cu concentration is less than 40 g / L, the Zn concentration is less than 200 g / L, and the concentrations of the other main impurity components are less than 5 g / L; the high-acid leaching solution containing gallium and germanium is a sulfuric acid leaching solution containing gallium and germanium, and the sulfuric acid concentration ranges from 10 to 130 g / L.

[0040] Furthermore, in step S1, the extraction temperature of liquid-liquid extraction I is 20-60°C, O / A=1:1-5:1; the extraction time is 2-30 min, and the extraction level is 2-5.

[0041] Furthermore, in step S2, the stripping temperature in stripping I is 20-60°C, O / A=1:1-1:10, the stripping time is 10-30 min, and the stripping stage number is 2-5.

[0042] Furthermore, in step S2, the substance of the structure of formula (4) is a gallium and iron stripping agent, which is an organic acid or an organic salt; in step S2, the concentration of the solution of formula (4) used in stripping I is 1.0 to 2.0 mol / L.

[0043] Furthermore, in step S31, the substance with the structure of formula (5) is a germanium stripping agent, which is an organic salt, and the concentration of the solution of formula (5) used in stripping II is 1.0 to 3.0 mol / L.

[0044] Furthermore, in step S31, the stripping temperature in stripping II is 30-65°C, the ratio O / A is 1:1-1:10, the stripping time is 15-30 min, and the stripping stages are 2-5. The loaded organic phase after stripping II can be recycled for liquid-liquid extraction I in step S2.

[0045] Furthermore, in step S32, the germanium stripping solution II is introduced into the reaction of liquid ammonia, the reaction time is 60 to 120 minutes, and the reaction temperature is 40 to 80°C; the filtered germanium enriched product II is dried and calcined at a temperature of 450 to 650°C for more than 2 hours to obtain a germanium concentrate; and the filtered filtrate can be used for cyclic stripping I.

[0046] Furthermore, in step S41, the amount of the ion precipitant of formula (6) added is such that the molar ratio of its effective component to the total amount of gallium and iron ions in the gallium- and iron-containing stripping solution I is 1.5:1 to 3:1, the reaction time is 10 min to 60 min, and the reaction temperature is 10 to 80° C. The ion precipitant of formula (6) is an ion precipitant used in the gallium- and iron-containing stripping solution I, and the solid effective component is 95% or the aqueous effective component is greater than 50%. After filtering to obtain the gallium and iron enriched product I, the filtrate is returned to the stripping I for cyclic stripping.

[0047] Furthermore, in step S42, the concentration of the sodium hydroxide solution added to the gallium and iron enriched product I is 120-200 g / L, the liquid-to-solid ratio of the sodium hydroxide solution to the gallium and iron enriched product I is 4-8, the reaction temperature is 30-80°C, the reaction time is 1-4 hours, the gallium concentration of the filtrate is measured by filtering, and the gallium concentration is circulated and enriched to a gallium concentration of 20-80 g / L, and then metallic gallium is prepared by electrolysis.

[0048] The present invention adopts the above technical solution and has the following advantages compared with the prior art:

[0049] (1) The method of the present invention is to extract, separate and enrich gallium and germanium from the sulfuric acid leaching solution containing gallium and germanium through one-step extraction (i.e., liquid-liquid extraction I) and step-by-step stripping (i.e., stripping I and stripping II), respectively, and the extraction rates of gallium and germanium are both greater than 98%; the stripping solution I of gallium and iron obtained after stripping I is precipitated to enrich gallium and iron, and the precipitation rate is greater than 70%, and the enriched product I of gallium and iron is neutralized and precipitated, and then alkali is circulated to separate gallium from iron, and after enriching gallium, electrolysis is performed to prepare metallic gallium, and the gallium grade is greater than 99.9%; the stripping solution II of germanium obtained after stripping II is neutralized and precipitated by liquid ammonia to enrich germanium, and dried and calcined to prepare germanium concentrate, and the germanium grade is greater than 50%; the two stripping solutions are recycled after removing gallium and germanium, the stripping agent consumption is small, and the gallium and germanium recovery rate is greater than 96%. The overall technology does not introduce other harmful impurities such as chlorine, and the process method is simple, the production cost is low, and it has wide industrial application value.

[0050] (2) In the composite organic phase used in liquid-liquid extraction I, the hydroxime chelating extractant of structure (1) has a long carbon chain and low water solubility, which meets the requirements of recycling; the alkylphenoxy phosphates of structures (21) and (22) have high acidity due to the electron-withdrawing effect of the benzene ring. They can undergo hydrogen ionization in a high-acid system and can undergo ion exchange with gallium to achieve the purpose of high-acid extraction without the need for acid adjustment.

[0051] (3) Stripping I is performed using an organic acid or organic salt solution of a gallium and iron stripping agent of formula (4) to obtain a stripping solution I of gallium and iron, thereby solving the problem of stripping of alkylphenoxy phosphate and avoiding the problem of decomposition of the hydroxamic acid extractant caused by high acid stripping in the P204+YW100 system used in the prior art.

[0052] (4) The gallium and iron stripping solution I is added with an ion precipitant having a structure of formula (6) to obtain a gallium and iron enriched product I. The organic acid or organic salt in the gallium and iron stripping solution I is released and can be recycled, thereby saving operating costs.

[0053] For better understanding and implementation, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 The present invention is a process flow chart of the method for preparing metallic gallium and germanium concentrate by synergistic extraction from high-acid gallium and germanium leaching solutions. DETAILED DESCRIPTION

[0055] The present invention is further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto.

[0056] The high-acid leaching solution containing gallium and germanium is industrially produced during the zinc smelting process. The main impurity elements in the leaching solution are Fe, Zn, Co, Ni, Cu, As, Cd, etc.

[0057] A method for preparing metallic gallium and germanium concentrate by synergistic extraction from high-acid leaching solution containing gallium and germanium. Figure 1 The process flow is as follows:

[0058] Step S1: The high-acid leaching solution containing gallium and germanium is subjected to liquid-liquid extraction I with a composite organic phase, the extraction temperature is 20-60°C, the phase ratio O / A is 1:1-5:1; the extraction time is 2-30 minutes, and the extraction level is 2-5 levels; the composite organic phase comprises the following components: 2%-30% of a hydroxyoxime chelating extractant of the structure of formula (1); 20%-30% of an alkylphenoxy phosphate extractant; 5%-10% of an alcohol modifier of the structure of formula (3), and the rest is a kerosene diluent.

[0059] Formula (1):

[0060]

[0061] Wherein, R1 is one of C9-C18 alkyl groups;

[0062] The alkylphenoxy phosphate extractant comprises 88-90 mol% of a monophosphate of formula (21) and 12-10 mol% of a diphosphate of formula (22);

[0063] Formula (21):

[0064]

[0065] Formula (22):

[0066]

[0067] Wherein, in formula (21) and formula (22), R2 is one of C8-C12 alkyl groups;

[0068] Formula (3):

[0069]

[0070] In step S1, the concentrations of gallium and germanium in the high-acid leaching solution containing gallium and germanium are both 0.1-3 g / L, and the main impurities in the high-acid leaching solution containing gallium and germanium include Fe, Cu, Zn, Sb, As, Co, and Ni, among which Cu is less than 40 g / L, Zn is less than 200 g / L, and the rest are less than 5 g / L.

[0071] In step S1, the high-acid leaching solution containing gallium and germanium is a sulfuric acid leaching solution containing gallium and germanium, and the sulfuric acid concentration ranges from 10 to 130 g / L.

[0072] Step S2: The loaded organic phase after liquid-liquid extraction I is stripped I with a solution containing a substance having a structure of formula (4) to obtain a loaded organic phase and a stripping solution I of gallium and iron; the loaded organic phase after stripping I enters step S3, and the stripping solution I of gallium and iron enters step S4.

[0073] Formula (4):

[0074]

[0075] Among them, M4 is H + 、Na + , K + NH4 + One of them.

[0076] In step S2: the temperature of stripping I is 20-60°C, the ratio O / A is 1:1-1:10, the stripping time is 10-30min, and the stripping level is 2-5; the structural substance of formula (4) is gallium and iron stripping agent, which is an organic acid or organic salt, and the solution concentration of formula (4) is 1.0-2.0 mol / L.

[0077] Step S3:

[0078] Step S31: The loaded organic phase obtained by stripping I in step S2 is stripped II with a solution containing a substance having the structure of formula (5) to obtain stripping solution II of germanium. The organic phase after stripping II is regenerated and cyclically extracted, and the stripping solution II of germanium enters step S32.

[0079] Formula (5):

[0080]

[0081] Among them, M5 is NH4 + .

[0082] In step S31, the temperature of stripping II is 30-65°C, the ratio O / A is 1:1-1:10, the stripping time is 15-30min, and the stripping level is 2-5; the structural substance of formula (5) is a germanium stripping agent organic salt, and the concentration of the solution of formula (5) is 1.0-3.0 mol / L.

[0083] Step S32: liquid ammonia is introduced into the germanium stripping solution II obtained in step S31 to react and neutralize to an end point pH value of 8.5 to 10.

[0084] The reaction time is 60 to 120 minutes, the reaction temperature is 40 to 80° C., and the filtrate is filtered and returned to step 3 for cyclic stripping; the filtered germanium enriched product II is dried and calcined at a temperature of 450 to 650° C. for a calcination time of more than 2 hours to obtain a germanium concentrate.

[0085] Step S4:

[0086] Step S41: adding an ion precipitant of formula (6) to the gallium and iron stripping solution I obtained in step S2, wherein the amount of the ion precipitant added is such that the molar ratio of its effective component to the sum of the gallium and iron ions in the gallium and iron stripping solution I is 1.5:1 to 3:1, the reaction time is 10 min to 60 min, and the reaction temperature is 10 to 80° C. filtering to obtain a gallium and iron enriched product I and entering step S42, and the filtrate is returned to step S2 for cyclic stripping.

[0087] Formula (6):

[0088]

[0089] Among them, M3 is H + 、Na + , K + NH4 + One of them.

[0090] Step S42: adding sodium hydroxide solution to the gallium and iron enriched product I obtained in step S41, with a concentration of 120-200 g / L, a liquid-to-solid ratio of 4-8, a reaction temperature of 30-80°C, a reaction time of 1-4 h, filtering, measuring the gallium concentration in the filtrate and cyclically enriching it to a gallium concentration of 20-80 g / L, and then electrolytically preparing metallic gallium.

[0091] Example 1

[0092] A method for preparing metallic gallium and germanium concentrate by synergistic extraction from high-acid leaching solution containing gallium and germanium. Figure 1 The process flow is as follows:

[0093] Step S1: subjecting the gallium- and germanium-containing high-acid leaching solution to liquid-liquid extraction I with the composite organic phase.

[0094] In this embodiment, the high-acid leaching solution containing gallium and germanium is an industrially produced sulfuric acid leaching solution containing gallium and germanium, wherein the sulfuric acid concentration is 25 g / L. For the concentrations of Ga, Ge, Fe, As, Zn, Co, Ni, Cd, and Cu, please refer to Table 1.

[0095] In this embodiment, the composite organic phase composition is: 10 vol% hydroxime chelating extractant+20 vol% alkyl phenoxy phosphate extractant+10 vol% alcohol modifier+60 vol% 260# sulfonated kerosene.

[0096] in:

[0097] The hydroxamic chelating extractant of this embodiment has the following structure:

[0098]

[0099] The alkylphenoxy phosphate extractant of this embodiment includes 88 mol % of monophosphate and 12 mol % of diphosphate.

[0100] Monophospholipids have the following structure:

[0101]

[0102] Bisphosphates have the following structure:

[0103]

[0104] The alcohol modifying agent of the present embodiment has the following structure:

[0105]

[0106] In this embodiment, a separatory funnel is used for two-stage extraction, the extraction temperature is 35° C., the extraction phase ratio O / A=1:1, and the extraction time is 10 min.

[0107] Table 1 Separation results of liquid-liquid extraction process I of Example 1

[0108]

[0109]

[0110] The results in Table 1 show that during the liquid-liquid extraction I extraction process, the single-stage extraction rates of gallium and germanium were 98.86% and 100%, respectively, among which iron was co-extracted, and the extraction rate of iron reached 96.88%, and other impurities were extracted in trace amounts.

[0111] Step S2: The loaded organic phase after liquid-liquid extraction I was subjected to 2-stage 1.5 mol oxalic acid solution stripping I using a separatory funnel to obtain a loaded organic phase and stripping solution I of gallium and iron (referred to as gallium stripping solution in Table 2). The stripping solutions I of gallium and iron obtained from the two strippings were mixed and the gallium stripping rate was calculated. The results are shown in Table 2 below. The stripping temperature in stripping I was 45° C., the ratio O / A was 1:1, and the stripping time was 15 min.

[0112] The oxalic acid used in this embodiment has the following structure:

[0113]

[0114] Among them, M4 is H + .

[0115] Step S3:

[0116] Step S31: The loaded organic phase after stripping I in step S2 is stripped II with 2 mol 2,3-dihydroxy-succinic acid diammonium salt solution using a separatory funnel to obtain germanium stripping solution II (in Table 2, germanium stripping solution), and the stripping solutions II of germanium stripped twice are mixed to calculate the germanium stripping rate. For the results, please refer to Table 2 below. The stripping temperature in stripping II is 45° C., the ratio O / A is 1:1, and the stripping time is 15 min.

[0117] The 2,3-dihydroxy-succinic acid diammonium salt of the present embodiment has the following structure:

[0118]

[0119] Among them, M5 is NH4 + .

[0120] Table 2 Separation results of stripping I and stripping II in Example 1

[0121]

[0122]

[0123] From the results in Table 2, it can be seen that after gallium and germanium are stripped at two stages, the stripping rate of gallium can reach 96.55%, and the stripping rate of germanium can reach 98.36%. The impurity Fe is stripped simultaneously with gallium during the stripping process of gallium, and the stripping rate of iron reaches 96.77%. The remaining iron is completely stripped out during the stripping process of germanium.

[0124] Step S32: The germanium stripping solution II in S31 is circulated and enriched to obtain a high-concentration germanium stripping solution II (see Table 3, which refers to germanium stripping solution in Table 3), and liquid ammonia is introduced into the high-concentration germanium stripping solution II (2L) for neutralization. When the pH is neutralized to 9.0, the reaction is performed for 2 hours and filtered to obtain a wet germanium concentrate. The wet germanium concentrate is set at a temperature of 550° C. in a muffle furnace, calcined for 4 hours, and then crushed to obtain 31.8 g of germanium concentrate. The results are shown in Table 3.

[0125] Table 3 Separation results of the germanium stripping solution of Example 1 passing into liquid ammonia

[0126] Element Ga Ge Fe As Zn Cu Germanium stripping solution (g / L) 0.5 10.15 0.9 0.01 0.1 0.1 Liquid after precipitation (g / L) 0 1.8 0 0.005 0.05 0.05 Sedimentation rate (%) 100 82.27 100 50 50 50 Germanium concentrate (%) 3.14 52.52 5.66 0.03 0.3 0.3

[0127] Step S4:

[0128] Step S41: The gallium and iron stripping solution I obtained in step S2 is circulated and enriched to obtain a high-concentration gallium and iron stripping solution I (see Table 4, which refers to the gallium stripping solution in Table 4), and 252g of an aminotri(methylenephosphonic acid) ion precipitant with an effective content of 95% (the molar ratio of the total effective content to the total amount of gallium and iron ions in the gallium and iron stripping solution I is 3:1) is added to the high-concentration gallium and iron stripping solution I (1L), and the reaction is carried out at 45°C for 30min, and 385g of a white precipitate containing water is obtained by suction filtration. After high-temperature drying and dehydration, 98g of an enriched product I containing 9.18% gallium and 5.10% iron is obtained.

[0129] The aminotri(methylenephosphonic acid) of the present embodiment has the following structure:

[0130]

[0131] Among them, M3 is H + .

[0132] Step S42: For the gallium and iron enriched product I obtained in step S41, 400 mL of 200 g / L sodium hydroxide was used to dissolve the enriched product I (the above 98 g of the enriched product I containing 9.18% gallium and 5.10% iron), and the reaction was carried out at 80° C. for 120 min. A brown-red precipitate (iron slag) appeared, and the alkaline filtrate was obtained by filtration (see Table 4).

[0133] Table 4 Separation results of the gallium stripping solution circulating enrichment solution of Example 1 for precipitation and alkaline dissolution process

[0134] Element Ga Ge Fe As Zn Cu Gallium stripping solution (g / L) 11.5 0.15 6.5 0 0.5 0.1 Sedimentation rate (%) 78.26 80.00 76.92 0 10.00 50 Liquid after precipitation (g / L) 2.5 0.12 1.5 0 0.45 0.05 Alkali solution (g / L) 21.5 0.3 0.001 0 0.10 0.01

[0135] As shown in Table 4, the gallium precipitation rate is 78.26%. The precipitated solid is dissolved in a high concentration alkali solution to transfer gallium into the alkali solution, and the gallium dissolution rate is 95.56%, which can achieve the separation of gallium and iron. The alkali-dissolved liquid is electrolytically deposited to obtain metallic gallium containing 99.9% gallium.

[0136] Example 2

[0137] A method for preparing metallic gallium and germanium concentrate by synergistic extraction from high-acid gallium and germanium leaching solution. Figure 1 The process flow is as follows:

[0138] Step S1: subjecting the gallium- and germanium-containing high-acid leaching solution to liquid-liquid extraction I with the composite organic phase.

[0139] In this embodiment, the high-acid leaching solution containing gallium and germanium is an industrially produced sulfuric acid leaching solution containing gallium and germanium, wherein the sulfuric acid concentration is 45 g / L. For the concentrations of Ga, Ge, Fe, As, Zn, Co, Ni, Cd, and Cu, please refer to Table 5.

[0140] In this embodiment, the composite organic phase composition is: 15 vol% hydroxime chelating extractant+25% alkyl phenoxy phosphate extractant+10 vol% alcohol modifier+50 vol% 260# sulfonated kerosene.

[0141] in:

[0142] The hydroxamic chelating extractant of this embodiment has the following structure:

[0143]

[0144] The alkylphenoxy phosphate extractant of this embodiment includes 90 mol % of monophosphate and 10 mol % of diphosphate.

[0145] Monophospholipids have the following structure:

[0146]

[0147] Bisphosphates have the following structure:

[0148]

[0149] The alcohol modifying agent of the present embodiment has the following structure:

[0150]

[0151] In this example, a separatory funnel was used for three-stage extraction, the extraction temperature was 35° C., the extraction phase ratio O / A=1:1, and the extraction time was 10 min. The results are shown in Table 5.

[0152] Table 5 Separation results of liquid-liquid extraction process I of Example 2

[0153]

[0154] The results in Table 5 show that the single-stage extraction rates of gallium and germanium during the liquid-liquid extraction I extraction process were 98.43% and 100%, respectively, and iron was co-extracted with an extraction rate of 78.61%, of which trace amounts were extracted.

[0155] Step S2: The loaded organic phase after liquid-liquid extraction I was subjected to 4-stage 1.5 mol oxalic acid solution gallium stripping I using a separatory funnel to obtain a stripping solution I of the loaded organic phase, gallium and iron (referred to as gallium stripping solution in Table 6), and the gallium stripping rate was calculated after the stripping solutions I of gallium and iron obtained by 4 stripping were mixed. The results are shown in Table 6 below. The stripping temperature in stripping I was 45° C., the phase ratio O / A was 1:1, and the stripping time was 15 min.

[0156] The oxalic acid used in this embodiment has the following structure:

[0157]

[0158] Among them, M4 is H + .

[0159] Step S3:

[0160] Step S31: The loaded organic phase after stripping I in step S2 is stripped II with 2.5 mol 2,3-dihydroxy-succinic acid diammonium salt solution in four stages using a separatory funnel to obtain germanium stripping solution II (referred to as germanium stripping solution in Table 6). The stripping solutions II of germanium stripped four times are mixed and the germanium stripping rate is calculated. The results are shown in Table 6 below. The stripping temperature in stripping II is 45° C., the ratio O / A is 1:1, and the stripping time is 15 min.

[0161] The 2,3-dihydroxy-succinic acid diammonium salt of the present embodiment has the following structure:

[0162]

[0163] Among them, M5 is NH4 + .

[0164] Table 6 Separation results of stripping I and stripping II in Example 2

[0165]

[0166] From the results in Table 6, it can be seen that after 4 stages of gallium and germanium stripping, the gallium stripping rate reaches 98.41%, among which the impurity iron is co-extracted during the extraction process. In the gallium stripping process, iron and gallium are stripped at the same time, and the iron stripping rate reaches 96.55%. The remaining iron is all stripped out during the germanium stripping process.

[0167] S32: The germanium stripping solution II in S31 is circulated and enriched to obtain a high-concentration germanium stripping solution II (see Table 7, referring to the germanium stripping solution in Table 7), and liquid ammonia is introduced into the high-concentration germanium stripping solution II (2L) for neutralization. When the neutralization pH is 9.0, the reaction is performed for 2 hours and filtered to obtain a wet germanium concentrate. The wet germanium concentrate is set at a temperature of 550° C. in a muffle furnace, calcined for 4 hours, and then crushed to obtain 31.65 g of germanium concentrate. The results are shown in Table 7.

[0168] Table 7 Separation results of the germanium stripping solution of Example 2 passing into liquid ammonia

[0169] Element Ga Ge Fe As Zn Cu Germanium stripping solution (g / L) 0 10.15 0.5 0.01 0.1 0.1 Liquid after precipitation (g / L) 0 1.8 0 0.005 0 0 Sedimentation rate (%) 0 82.27 100 50 100 100 Germanium concentrate (%) 0 52.76 3.16 0.03 0.63 0.63

[0170] Step S4:

[0171] Step S41: The gallium and iron stripping solution I obtained in step S2 is circulated and enriched to obtain a high-concentration gallium-containing solution (see Table 8, which refers to the gallium stripping solution in Table 8), 1L of the gallium and iron stripping solution I is taken, 370g of an aminotri(methylenephosphonic acid) ion precipitant with an effective content of 95% is added (the molar ratio of the total effective amount to the total amount of gallium and iron ions in the gallium and iron stripping solution I is 3:1), the reaction is carried out at 45°C for 30min, and 310g of a white precipitate containing water is obtained by suction filtration. After high-temperature drying and dehydration, 148g of an enriched product I containing 6.43% gallium and 10.47% iron is obtained.

[0172] The aminotri(methylenephosphonic acid) of the present embodiment has the following structure:

[0173]

[0174] Among them, M3 is HH + .

[0175] Step S42: For the gallium and iron enriched product I obtained in step S41, 600 mL of 180 g / L sodium hydroxide was used to dissolve the enriched product I (148 g of the enriched product I containing 6.43% gallium and 10.47% iron), and the reaction was carried out at 80° C. for 120 min. A brown-red precipitate (iron slag) appeared, and the gallium-containing filtrate was obtained by filtration, as shown in Table 3.

[0176] Table 8 Separation results of the gallium stripping solution circulating enrichment solution of Example 2 for precipitation and alkaline dissolution process

[0177] Element Ga Ge Fe As Zn Cu Gallium stripping solution (g / L) 12.5 0.05 20.15 0 0.3 0 Sedimentation rate (%) 76.16 60.00 76.92 0 50.00 0 Liquid after precipitation (g / L) 2.98 0.02 4.65 0 0.15 0 Alkali solution (g / L) 15.5 0.05 0.1 0 0.25 0

[0178] As can be seen from Table 8, the gallium precipitation rate is 76.16%. The precipitated solid is dissolved in a high-concentration alkaline solution to transfer the gallium into the alkaline solution. The gallium dissolution rate is 97.67%, which can achieve the separation of gallium and iron. The alkaline-dissolved liquid is circulated for enrichment. When the gallium concentration is greater than 20g / L, metallic gallium containing 99.9% gallium is obtained by electrolysis.

[0179] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, and the present invention is also intended to include these modifications and modifications.

Claims

1. A method for preparing metallic gallium and germanium concentrate by synergistic extraction, characterized in that: The following steps are involved: Step S1: subjecting the high-acid leaching solution containing gallium and germanium to liquid-liquid extraction I with a composite organic phase; the composite organic phase comprises the following components: 2 vol% to 30 vol% of a hydroxime chelating extractant of formula (1), 20 vol% to 30 vol% of an alkylphenoxy phosphate extractant, 5 vol% to 10 vol% of an alcohol modifier of formula (3), and the remainder being a kerosene diluent; wherein: Formula (1): Wherein, R1 is one of C9-C18 alkyl groups; The alkylphenoxy phosphate extractant comprises 88-90 mol% of a monophosphate of formula (21) and 12-10 mol% of a diphosphate of formula (22); Formula (21): Formula (22): Wherein, in formula (21) and formula (22), R2 is one of C8-C12 alkyl groups; Formula (3): Step S2: The loaded organic phase obtained by the liquid-liquid extraction I in step S1 is stripped I using a solution of formula (4) to obtain a stripping solution I containing the loaded organic phase and gallium and iron; Formula (4): Among them, M4 is H + 、Na + , K + NH4 + One of; Step S3 includes: Step S31: The loaded organic phase obtained by stripping I in step S2 is stripped II using a solution of formula (5) to obtain a stripping solution II of germanium; Formula (5): Among them, M5 is NH4 + ; Step S32: introducing liquid ammonia into the germanium stripping solution II obtained in step S31, reacting and neutralizing to an end point pH value of 8.5-10, filtering to obtain a germanium enriched product II, and drying and calcining the germanium enriched product II to obtain a germanium concentrate; Step S4 comprises: Step S41: adding an ion precipitant of formula (6) to the stripping solution I containing gallium and iron obtained in step S2, and filtering to obtain a gallium and iron enriched product I; Formula (6): Among them, M3 is H + 、Na + , K + NH4 + One of; Step S42: adding sodium hydroxide solution to the gallium and iron enriched product I obtained in step S42, filtering, measuring the gallium concentration in the filtrate, or cyclically enriching until the gallium concentration is 20 to 80 g / L and then electrolyzing to prepare metallic gallium.

2. The method for preparing metallic gallium and germanium concentrate by synergistic extraction according to claim 1, characterized in that: In step S1, the high-acid leaching solution containing gallium and germanium contains 0.1-3 g / L of gallium and 0.1-3 g / L of germanium, and the main impurities include Fe, Cu, Zn, Sb, As, Co and Ni, wherein the Cu concentration is less than 40 g / L, the Zn concentration is less than 200 g / L, and the concentrations of the other main impurity components are less than 5 g / L; the high-acid leaching solution containing gallium and germanium is a sulfuric acid leaching solution containing gallium and germanium, and the sulfuric acid concentration ranges from 10 to 130 g / L.

3. The method for preparing metallic gallium and germanium concentrate by synergistic extraction according to claim 1, characterized in that: In step S1, the extraction temperature of liquid-liquid extraction I is 20-60°C, the ratio O / A is 1:1-5:1, and the extraction time is 2-30 min.

4. The method for preparing metallic gallium and germanium concentrate by synergistic extraction according to claim 1, characterized in that: In step S2, the stripping temperature of stripping I is 20-60°C, O / A=1:1-1:10, and the stripping time is 10-30 min.

5. The method for preparing metallic gallium and germanium concentrate by synergistic extraction according to claim 1, characterized in that: In step S2, the concentration of the solution of formula (4) is 1.0 to 2.0 mol / L.

6. The method for preparing metallic gallium and germanium concentrate by synergistic extraction according to claim 1, characterized in that: In step S31, the concentration of the solution of formula (5) used in stripping II is 1.0 to 3.0 mol / L.

7. The method for preparing metallic gallium and germanium concentrate by synergistic extraction according to claim 1, characterized in that: In step S31, the stripping temperature of stripping II is 30-65°C, O / A=1:1-1:10; the stripping time is 15-30 min, and the stripping stage number is 2-5.

8. The method for preparing metallic gallium and germanium concentrate by synergistic extraction according to claim 1, characterized in that: In step S32, liquid ammonia is introduced into the germanium stripping solution II for a reaction time of 60 to 120 minutes at a temperature of 40 to 80°C; the filtered germanium enriched product II is dried and calcined at a temperature of 450 to 650°C for a time of more than 2 hours.

9. The method for preparing metallic gallium and germanium concentrate by synergistic extraction according to claim 1, characterized in that: In step S41, the amount of the ion precipitant of formula (6) added is such that the molar ratio of its effective component to the sum of the total amount of gallium and iron ions in the gallium- and iron-containing stripping solution I is 1.5:1 to 3:1, the reaction time is 10 min to 60 min, and the reaction temperature is 10 to 80°C.

10. The method for preparing metallic gallium and germanium concentrate by synergistic extraction according to claim 1, characterized in that: In step S42, the concentration of the sodium hydroxide solution is 120-200 g / L, the liquid-to-solid ratio of the sodium hydroxide solution to the gallium and iron enriched product I is 4-8, the reaction temperature is 30-80° C., and the reaction time is 1-4 h.

Images