A method for extracting germanium with solvent and preparing germanium concentrate

Abstract

The present invention relates to the technical field of extraction of scattered metallic germanium, especially a method for secondary extraction of germanium from hydrolyzed liquid in an octyl decyl tertiary amine-tartaric acid system and preparation of germanium concentrate, specifically: A) mixing feed liquid, secondary raffinate, and acidified organic phase for primary extraction; B) mixing a primary load organic phase, hydrolyzed liquid, and washing water phase for secondary extraction; C) mixing a secondary load organic phase and a sodium hydroxide solution for stripping; D) mixing an empty organic phase, a sulfuric acid solution, and / or an acidified liquid for acidification transformation; E) mixing stripping liquid, partially acidified liquid, and magnesium sulfate for hydrolysis, washing a hydrolysis filter cake, and drying the washed filter cake to produce a germanium concentrate. The germanium concentrate of the present invention has low germanium metal sodium hydroxide unit consumption, high grade, and low tartaric acid unit consumption.

Description

Technical Field

[0001] The invention relates to a method for extracting germanium in a sulfate solution by using an octyl decyl alkyl tertiary amine-tartaric acid system and preparing germanium concentrate, in particular to a method for extracting germanium twice by using a hydrolyzed liquid and preparing germanium concentrate, belonging to the technical field of extracting scattered metallic germanium. Background Art

[0002] The method of extracting germanium and preparing germanium concentrate by using an octyl decyl alkyl tertiary amine-tartaric acid system generally includes the steps of preparing a feed solution, extracting, stripping, and preparing germanium concentrate by stripping solution.

[0003] The preparation of the feed solution is to leach the germanium-containing material with sulfuric acid solution or sulfuric acid-tartaric acid mixed solution, transfer the germanium into the solution, and add or supplement tartaric acid to form an acidic sulfate solution containing germanium tartaric acid complex. Generally, the leachate should be purified, such as gelatin flocculation desiliconization, iron powder reduction, etc., to obtain a feed solution that meets the requirements of industrial continuous extraction.

[0004] Extraction is to mix the feed liquid with the empty organic phase to transfer the germanium tartaric acid complex into the organic phase. The complexation reaction between germanium ions and tartaric acid is:

[0005] Ge 4+ + 3C4O6H6 = [Ge(C4O6H4)3] 2+ + 6H + ;

[0006] Theoretically, 1 mol of germanium requires 3 mol of tartaric acid for complexation, that is, 1 kg of germanium requires 6.2 kg of tartaric acid for complexation.

[0007] Stripping is to mix sodium hydroxide solution with the loaded organic phase, decompose the germanium tartaric acid complex, and transfer germanium into the water phase. In order to meet the requirements of germanium hydrolysis, a high-content sodium hydroxide solution is generally used for cyclic stripping, and sodium hydroxide is appropriately supplemented during the process.

[0008] The stripping solution is used to prepare germanium concentrate by neutralizing the stripping solution with an acidic solution to promote the hydrolysis of germanium, thereby obtaining germanium concentrate.

[0009] Chinese patent CN 1020711C discloses a method for recovering germanium from an acidic solution containing germanium, wherein an organic phase containing 3% (volume percentage) trioctyldecyl tertiary amine is used to extract germanium from an acidic aqueous solution adjusted to pH 0.8-1.3 with sulfuric acid, at least 2.15 kg of tartaric acid is added to the acidic aqueous solution for complexation per kilogram of germanium, the loaded organic phase contains 0.45 g / L-1.5 g / L of germanium, and is washed with fresh water. The washed organic phase is stripped with 4.5 N-5.0 N sodium hydroxide solution, sulfuric acid is added to the stripping solution to adjust the pH to 8-11, and the stripping solution is hydrolyzed and filtered at 70° C.-80° C. to obtain a precipitate, the washing water and the solution after hydrolysis contain tartaric acid, which is returned to the extraction, so that part of the tartaric acid is consumed and more than 75% is recycled, and the empty organic phase is returned to the extraction. However, this method has low extractant concentration, high organic phase load, large Vo / Va ratio between washing and stripping, and is difficult to achieve continuous extraction production. The consumption of tartaric acid and sodium hydroxide is inconsistent with production practice, and the method fails to provide the grade of precipitated germanium metal and the recovery rate of germanium.

[0010] Chinese patent CN 101538653 B discloses a method for producing germanium concentrate from industrial feed liquid containing germanium, wherein germanium is extracted from industrial feed liquid containing germanium with a pH value of 0.5 to 3 using an organic phase containing 20% ​​to 30% tetraalkylamine or trialkylamine, 3.0kg to 10.0kg of complexing agent is added to each kilogram of germanium in the industrial feed liquid containing germanium, the loaded organic phase is stripped with 5% to 30% sodium hydroxide or sodium carbonate solution, the stripping solution is adjusted to pH 8 to 12 with acid for secondary hydrolysis, and Mg is used to extract the germanium concentrate. 2+ The metal ions were used as precipitation aids for the second hydrolysis, and the secondary precipitate was returned to the first hydrolysis to produce a germanium concentrate with a grade of 11.5%. The complexing agent was recovered from the hydrolysis residue by crystallization. However, the complexing agent in this method includes citric acid, citrate, tartaric acid, and tartrate. The crystallization recovery method was not fully explained, and it was not returned to the system for use. The consumption of sodium hydroxide was unclear, and the grade of the germanium concentrate was low.

[0011] Chinese patent CN 1020711C states that the only ion that can be extracted to a certain extent from the extraction of germanium by the octyldecyl tertiary amine-tartaric acid system is the hydrogen sulfate ion [HSO4 - ], while Chinese patent CN 101538653 B points out that the feed liquid contains Cl - 0.56g / L was reduced to Cl in the residual liquid after extraction - Below 160 mg / L, there is an obvious contradiction between the two.

[0012] Chinese patent CN 109929997 B discloses a method for producing germanium concentrate using N235 extractant, wherein an organic phase containing N235 is used to extract germanium from a germanium-containing acidic solution, 3.0kg to 5.0kg of an organic complex is added to the germanium-containing acidic solution for each kilogram of germanium, the loaded organic phase is washed with an organic acid solution corresponding to 0.1% to 5% of the organic complex, the washed loaded organic phase is then cyclically stripped with a sodium hydroxide solution until the stripping solution contains more than 20g / L of germanium, the stripping solution is hydrolyzed by adjusting the pH to 9 to 11 with sulfuric acid, the hydrolysis filter cake is washed and calcined to obtain a 30% to 50% germanium dioxide concentrate, the hydrolysis filtrate is causticized with calcium hydroxide or calcium oxide, the produced sodium hydroxide solution is returned for use, and the produced calcium-containing precipitate is leached with sulfuric acid and contains an organic complexing agent and is returned for use. This method ensures the extraction rate of germanium, greatly reduces the consumption of sodium hydroxide, improves the grade of germanium concentrate, regenerates sodium hydroxide and organic complexing agent of germanium, and reduces the cost of environmental treatment of waste residue and wastewater, which has good economic and environmental benefits. However, this method uses calcium hydroxide or calcium oxide to causticize sodium sulfate solution, the causticizing efficiency is low, the recovery of organic complexing agent increases the leaching of calcium-containing precipitates, and the process flow is cumbersome.

[0013] Obviously, improving the grade of germanium concentrate, reducing the unit consumption of germanium metal complexing agent, and reducing the unit consumption of germanium metal sodium hydroxide are the core tasks in the method of extracting germanium and preparing germanium concentrate using the octanol-decyl tertiary amine-tartaric acid system. Summary of the invention

[0014] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method for extracting germanium and preparing germanium concentrate using an octanyl tertiary amine-tartaric acid system with low germanium metal sodium hydroxide consumption, high germanium metal grade in germanium concentrate and low germanium metal tartaric acid consumption.

[0015] The technical solution of the present invention is: a method for solvent extraction of germanium and preparation of germanium concentrate, comprising the following steps:

[0016] The feed liquid, the secondary raffinate and the acidified organic phase are mixed and extracted once to produce a primary raffinate and a primary loaded organic phase, wherein the feed liquid is a sulfate solution containing germanium tartaric acid complex, the secondary raffinate contains tartaric acid as a complexing agent, the acidified organic phase contains trioctyldecyl tertiary amine as an extractant, and the primary raffinate is used for recycling other metals;

[0017] The primary loaded organic phase, the hydrolyzed liquid and the washing water phase produced in step A are mixed and subjected to secondary extraction to produce a secondary raffinate and a secondary loaded organic phase, wherein the hydrolyzed liquid and the washing water contain tartaric acid as a complexing agent, and the secondary raffinate is returned to step A for use;

[0018] The secondary loaded organic phase produced in step B and the sodium hydroxide solution are mixed and stripped to produce an empty organic phase and a stripping solution;

[0019] The unloaded organic phase, sulfuric acid solution and / or acidified liquid produced in step C are mixed and acidified to produce an acidified organic phase and an acidified liquid. The acidified organic phase is returned to step A for use, and the acidified liquid is partially returned to this step for use;

[0020] E) The stripping solution produced in step C, the partially acidified solution produced in step D and magnesium sulfate are mixed and hydrolyzed to produce a hydrolyzed solution and a hydrolysis filter cake. The hydrolysis filter cake is washed with fresh water to produce a washing filter cake and washing water. The hydrolyzed solution and washing water contain tartaric acid as a complexing agent and are returned to step B for use. The washing filter cake is dried to produce a germanium concentrate.

[0021] The octyl decyl tertiary amine extractant is a broad-spectrum anion extractant. In the sulfate solution, a small amount of chloride ions can form complex anions such as zinc, cadmium, bismuth, antimony, tin, and lead, which are easily extracted into the organic phase by the octyl decyl tertiary amine extractant, thereby increasing the concentration of impurity metal ions in the loaded organic phase. Preferably, the feed solution in step A is pretreated with dechlorination, and the mass volume concentration of chloride ions is less than 0.2 g / L.

[0022] The extraction process of metal complex anions by octanol tertiary amine extractants is an anion exchange process. In order to achieve this exchange, the octanol tertiary amine extractants must be treated with acid during extraction to form amine salts from the extraction acid. When the organic phase containing the amine salts comes into contact with the aqueous solution containing the metal complex anions, anion exchange occurs. Obviously, the higher the concentration of amine salts, the higher the efficiency of the anion exchange reaction. However, the higher the concentration of amine salts in the loaded organic phase, the greater the consumption of alkali during stripping and the crystallization of the stripping solution.

[0023] In practice, it is further preferred that the molar concentration ratio of the extractant trioctyl decyl alkyl tertiary amine in the acidified organic phase in step A to the molar concentration ratio of germanium in the feed solution is 22 to 24:1.

[0024] In the case of complete stripping, in order to make full use of the sodium hydroxide in the stripping agent, it is further preferred that the stripping in step C is a secondary countercurrent stripping, the secondary loaded organic phase is mixed with the secondary stripping liquid to perform a primary stripping, and a primary stripping liquid is produced as a stripping liquid, containing 2.0 g / L to 5.0 g / L of free sodium hydroxide, the produced primary stripping organic phase is mixed with the sodium hydroxide solution to perform a secondary stripping, and the produced secondary stripping organic phase is an empty organic phase.

[0025] In the hydrolysis of step E, firstly, part of the acidified solution produced in step D is added to the stripping solution produced in step C, the pH is adjusted to 9-10, and then magnesium sulfate is added to mix and hydrolyze.

[0026] More preferably, the amount of magnesium sulfate used is 5 to 7 times the weight of germanium in the solution.

[0027] The washed filter cake in step E contains impurities such as magnesium tartrate. In order to improve the grade of germanium concentrate, it is advisable to thermally decompose the organic matter.

[0028] More preferably, the drying temperature of the washed cake is 250°C to 300°C.

[0029] The hydrolysis filtrate and washing water not only contain most of the tartaric acid extracted into the organic phase, but also contain germanium ions that have not been hydrolyzed and precipitated and a small amount of free sodium hydroxide. The hydrolysis filtrate is mixed with washing water and the primary load organic phase for secondary extraction, which not only washes the primary load organic phase and removes some impurity ions, but also partially neutralizes the primary load organic phase, making full use of the sodium hydroxide input. The secondary raffinate is returned to the primary extraction, which can also significantly reduce the unit consumption of the complexing agent tartaric acid. In addition, the germanium in the hydrolysis filtrate and washing water is extracted into the organic phase again, achieving saturated extraction of the organic phase and increasing the germanium content and purity of the secondary load organic phase.

[0030] Preferably, the ratio of the secondary extraction in step B is Vo / Va = 10:3-4.

[0031] Beneficial effects of the present invention:

[0032] Germanium concentrate Germanium metal sodium hydroxide unit consumption is low: the germanium is extracted and prepared by using the octyl decyl alkyl tertiary amine-tartaric acid system. Sodium hydroxide is mainly consumed in the following two aspects: a) decomposition of germanium tartaric acid complex anions in the loaded organic phase; b) decomposition of other metal complex anions in the loaded organic phase. Compared with the prior art, the present invention uses dechlorination pretreatment on the sulfate solution containing germanium tartaric acid complex anions to reduce the concentration of chloride complex anions in the loaded organic phase, thereby reducing the consumption of sodium hydroxide; strictly control the concentration ratio of octyl decyl alkyl tertiary amine in the organic phase to the concentration ratio of germanium tartaric acid complex anions in the feed solution, and reduce the concentration of hydrogen sulfate ions [HSO 4- ] concentration, thereby reducing the unit consumption of sodium hydroxide; using the hydrolysis filtrate and washing water to mix with the primary load organic phase for secondary extraction, not only the primary load organic phase is pre-neutralized, but also the concentration and purity of the germanium complex anion in the secondary load organic phase are increased, thereby reducing the consumption of sodium hydroxide; implementing two-stage stripping, strictly controlling the concentration of free sodium hydroxide in the primary stripping solution, that is, implementing direct hydrolysis of the organic phase-loaded metal ions, avoiding excess free sodium hydroxide in the primary stripping solution, and reducing the consumption of sodium hydroxide.

[0033] Germanium concentrate has high germanium metal grade: Improving the germanium metal grade of germanium concentrate is essentially to increase the germanium metal content and reduce the impurity metal content. Compared with the prior art, the present invention performs dechlorination pretreatment on the feed liquid, strictly controls the concentration of trioctyldecyl tertiary amine in the organic phase, and uses hydrolysis filtrate and washing water to pre-neutralize and wash the primary load organic phase, which are all conducive to improving the germanium metal grade of the germanium concentrate. In addition, the present invention strictly controls the amount of magnesium sulfate as a precipitation aid in the stripping solution, which not only ensures the hydrolysis precipitation rate of germanium in the stripping solution, but also helps to ensure the germanium metal grade of the germanium concentrate. The magnesium tartrate contained in the water-washed filter cake is decomposed by controlling the temperature during drying, thereby improving the germanium metal grade of the germanium concentrate.

[0034] Germanium concentrate Germanium metal complexing agent Tartaric acid Low unit consumption Germanium forms complex anion [Ge(C4O6H4)3] with tartaric acid 2- , the ratio of the amount of substance is 1:3. Theoretically, 6.20kg of tartaric acid is required for each kilogram of germanium for complexation. The recovery of complexing agent tartaric acid has received widespread attention. There are mainly three methods: direct return of hydrolysis filtrate; return of hydrolysis filtrate after crystallization; return of hydrolysis filtrate after treatment. Compared with the prior art, the complexing agent of the present invention exists in the secondary raffinate and is directly returned to the extraction. The treatment measures are simple and easy, which not only ensures the direct recovery rate of germanium, avoids the liquid germanium metal from entering the large extraction cycle after hydrolysis, but also greatly reduces the consumption of complexing agent tartaric acid. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The present invention is a process flow chart of a method for preparing germanium concentrate by solvent extraction. DETAILED DESCRIPTION

[0036] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings and preferred embodiments so that those skilled in the art can achieve the purpose of the present invention, but the claims of the present invention are not limited to this description and preferred embodiments.

[0037] like Figure 1 As shown, the present invention relates to a method for extracting germanium and preparing germanium concentrate in a sulfate solution using an octyl decyl alkyl tertiary amine-tartaric acid system, comprising the steps of primary extraction, secondary extraction, stripping, acidification, hydrolysis, washing and drying.

[0038] The feed liquid is a sulfate solution containing germanium tartaric acid complex, which can generally be prepared by leaching germanium-containing materials with sulfuric acid solution or sulfuric acid-tartaric acid mixed solution, and tartaric acid is added or supplemented to form a sulfate solution containing germanium tartaric acid complex. In order to meet the requirements of industrial continuous extraction, the leachate can be subjected to gelatin flocculation desiliconization, reduced iron powder reduction and impurity removal treatment, etc. Octyl decyl alkyl tertiary amine is a broad-spectrum extractant, and its extraction process is an exchange process of anions or metal complex anions. In order to reduce the content of metal chloride complex anions in the loaded organic phase, the present invention performs dechlorination pretreatment on the feed liquid to make the chloride ion mass volume concentration <0.2g / L. Dechlorination pretreatment measures include but are not limited to ion exchange method, extraction method, and cuprous salt precipitation method.

[0039] The organic phase contains an extractant trioctyl decyl alkyl tertiary amine, a modifier sec-octanol or tributyl phosphate, and 260# solvent oil. In order to reduce the content of hydrogen sulfate ions in the organic phase, the present invention strictly controls the molar concentration ratio of the extractant trioctyl decyl alkyl tertiary amine in the organic phase to the molar concentration ratio of germanium in the feed liquid. Obviously, the greater the concentration ratio, the more conducive to germanium extraction, but at the same time, the higher the content of hydrogen sulfate ions in the organic phase. After practical optimization, the concentration ratio is preferably 22 to 24:1.

[0040] First, the feed liquid and the acidified organic phase are mixed for an extraction to produce a raffinate and a loaded organic phase, and the raffinate is used for recycling of other metals; then, the loaded organic phase and the tartaric acid solution are mixed for a secondary extraction to produce a secondary raffinate and a secondary loaded organic phase, and the secondary raffinate is returned to be mixed with the feed liquid for a primary extraction; then, the secondary loaded organic phase and the sodium hydroxide solution are mixed for stripping to produce an empty organic phase and a stripping solution; the empty organic phase and the sulfuric acid solution are mixed for acidification and transformation to produce an acidified organic phase and an acidified liquid, the acidified organic phase is returned for a primary extraction, and part of the acidified liquid is returned for recycling; finally, the stripping solution, part of the acidified liquid and magnesium sulfate are mixed for hydrolysis to produce a hydrolyzed liquid and a hydrolysis filter cake, the hydrolysis filter cake is washed with new water to produce a washing filter cake and washing water, the hydrolyzed liquid and the washing water contain a complexing agent, tartaric acid, which are returned for secondary extraction to replace the tartaric acid solution, and the washing filter cake is dried to produce a germanium concentrate.

[0041] The germanium-containing zinc oxide powder of a certain company was used for two-stage countercurrent leaching with sulfuric acid solution to prepare the leachate. The leachate was flocculated with bone gelatin for desiliconization. The desiliconized liquid was added with reduced iron powder to reduce copper and trivalent iron ions to obtain a purified liquid containing Zn 2+ 110.5g / L, Mn 2+ 21.1g / L, Fe 3+ 0.020g / L, Fe 2+ 3.25g / L, Cd 2+ 3.28g / L, Ge 4+1.20g / L, Ni 2+ 0.045g / L, Co 2+ 0.008g / L, Cu 2+ Not detected, F - 0.080g / L, CL - 3.15g / L, T AS 0.12g / L, Sb 0.010g / L, SiO20.045g / L, H2SO417.8g / L.

[0042] Comparative Example 1:

[0043] The molar concentration of germanium in the purified solution is 0.0165 mol / L, and the organic phase containing trioctyl decyl alkyl tertiary amine is prepared according to the molar concentration of the extractant trioctyl decyl alkyl tertiary amine in the organic phase and the molar concentration of germanium in the feed solution of 15:1. The newly prepared organic phase is mixed with 100g / L sulfuric acid solution at a ratio of Vo / Va=2:1 for 10 minutes, and the layers are allowed to stand to obtain the upper acidified organic phase, and the loaded organic phase contains 24.0g / L of hydrogen sulfate ions.

[0044] Take 10.0L of the purified liquid, add 72.0g of tartaric acid, mix well, and obtain a sulfate solution containing germanium tartaric acid complex, i.e., the feed liquid, and extract it with 5.0L of acidified organic phase in a small three-stage countercurrent mixer-clarifier, with a ratio of Vo / Va=1:2, a temperature of 30℃~35℃, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a raffinate containing Zn 2+ 109.3g / L, Mn 2+ 21.1g / L, Fe 3+ 0.020g / L, Fe 2+ 3.25g / L, Cd 2+ 1.23g / L, Ge 4+ 0.542g / L, Ni 2+ 0.045g / L, Co 2+ 0.008g / L, Cu 2 + Not detected, F - 0.080g / L, CL - 0.21g / L, T AS0.12g / L, Sb 0.010g / L, SiO20.045g / L, H2SO420.20g / L, tartaric acid 0.010g / L, the extraction rates of zinc, cadmium, germanium, chlorine and tartaric acid were 1.08%, 62.50%, 54.83%, 93.33% and 99.86% respectively, and the concentrations of zinc, cadmium, germanium, chlorine, hydrogen sulfate ion and tartaric acid in the loaded organic phase were 2.4g / L, 4.1g / L, 1.316g / L, 5.88g / L, 19.20g / L and 14.38g / L respectively.

[0045] Comparative Example 2:

[0046] The molar concentration of germanium in the purified solution is 0.0165 mol / L. The organic phase containing trioctyl decyl alkyl tertiary amine is prepared according to the molar concentration of the extractant trioctyl decyl alkyl tertiary amine in the organic phase and the molar concentration of germanium in the feed solution of 30:1. The newly prepared organic phase is mixed with 100g / L sulfuric acid solution at a ratio of Vo / Va=2:1 for 10 minutes, and the layers are allowed to stand to obtain the upper acidified organic phase. The loaded organic phase contains 48.02g / L of hydrogen sulfate ions.

[0047] Take 10.0L of the purified liquid, add 72.0g of tartaric acid, mix well, and obtain a sulfate solution containing germanium tartaric acid complex, i.e., the feed liquid, and extract it with 5.0L of acidified organic phase in a small three-stage countercurrent mixer-clarifier, with a ratio of Vo / Va=1:2, a temperature of 30℃~35℃, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a raffinate containing Zn 2+ 108.6g / L, Mn 2+ 21.1g / L, Fe 3+ 0.020g / L, Fe 2+ 3.25g / L, Cd 2+ 0.25g / L, Ge 4+ 0.007g / L, Ni 2+ 0.045g / L, Co 2+ 0.008g / L, Cu 2+ Not detected, F - 0.080g / L, CL - 0.16g / L, T AS0.12g / L, Sb 0.010g / L, SiO20.045g / L, H2SO426.30g / L, tartaric acid 0.010g / L, the extraction rates of zinc, cadmium, germanium, chlorine and tartaric acid were 1.72%, 92.37%, 99.42%, 94.92% and 99.86%, respectively, and the concentrations of zinc, cadmium, germanium, chlorine, hydrogen sulfate ion and tartaric acid in the loaded organic phase were 3.80g / L, 6.06g / L, 2.386g / L, 5.98g / L, 31.02g / L and 14.38g / L, respectively.

[0048] Comparative Example 3:

[0049] The mixed load organic phase of control example 1 and control example 2 was combined to obtain 10.0L, and the concentrations of zinc, cadmium, germanium, chlorine, hydrogen sulfate ion and tartaric acid were 3.10g / L, 5.06g / L, 1.848g / L, 5.93g / L, 25.11g / L and 14.38g / L, respectively. It was extracted with 5.0L of new water in a small secondary countercurrent mixer-clarifier, with Vo / Va=2:1, temperature 30℃~35℃, mixing time 10 minutes, standing for 10 minutes, and washing water containing Zn 2+ 1.64g / L, Cd 2+ 0.07g / L, Ge 4+ 0.015g / L, CL - 1.01g / L, H2SO43.26g / L, tartaric acid0.093g / L, the elution rates of zinc, cadmium, germanium, chlorine, hydrogen sulfate ion and tartaric acid were 26.45%, 0.69%, 0.40%, 8.52%, 6.49% and 0.32%, respectively, and the concentrations of zinc, cadmium, germanium, chlorine, hydrogen sulfate ion and tartaric acid in the loaded organic phase were 2.28g / L, 5.02g / L, 1.84g / L, 5.42g / L, 23.48g / L and 14.33g / L, respectively.

[0050] 2.0L of the washed loaded organic phase was mixed with 1.0L of 200g / L sodium hydroxide solution for back extraction, with a ratio of Vo / Va=2:1, a temperature of 30℃~35℃, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a back extract. A precipitate was precipitated in the back extract, and a filtrate was obtained by vacuum filtration, which contained Zn 2+ 4.54g / L, Cd 2+ 0.03g / L, Ge 4+ 3.67g / L, CL -10.83g / L, NaOH 140.0g / L, sulfate ion 46.95g / L, tartaric acid 28.65g / L, the stripping rates of zinc, germanium, chlorine, hydrogen sulfate ion and tartaric acid were 99.56%, 99.73%, 99.91%, 99.98% and 99.96% respectively, the concentrations of zinc, germanium, chlorine, hydrogen sulfate ion and tartaric acid in the loaded organic phase were 0.01g / L, 0.005g / L, 0.005g / L, 0.005g / L, 0.005g / L respectively, cadmium is insoluble in sodium hydroxide solution and is the main component of precipitation. It was not measured and tested, and the stripping rate of cadmium and the concentration in the empty organic phase were not calculated. The stripping filtrate was supplemented with 60.0g of sodium hydroxide, and then mixed with 2.0L of the washed loaded organic phase for stripping. This operation was repeated 3 times, consuming a total of 380.0g of sodium hydroxide to obtain 1.0L of stripping filtrate containing Zn 2+ 22.70g / L, Cd 2+ 0.06g / L, Ge 4+ 18.35g / L, CL - 54.15g / L, NaOH 140.0g / L, sulfate ion 234.75g / L, tartaric acid 143.0g / L.

[0051] Take 1.0L of the stripping filtrate, add 92.0mL (about 170.0g) of concentrated sulfuric acid dropwise under stirring to adjust the pH to 9.0, raise the temperature to 75℃ and keep the reaction for 2.0 hours, vacuum filter to obtain 87.6g of filter cake and 1.0L of filtrate, containing Zn 2+ 0.80g / L, Cd 2+ 0.06g / L, Ge 4+ 8.54g / L, CL - 54.15g / L, tartaric acid 143.0g / L, germanium hydrolysis precipitation rate 53.46%. Take 1.0L of filtrate, add 60.0g of magnesium sulfate heptahydrate according to 7 times the amount of germanium under stirring, raise the temperature to 75℃ and keep warm for 2.0 hours, vacuum filter, get 240.0g of filter cake, get 1.0L of filtrate, containing Zn 2+ 0.35g / L, Cd 2+ 0.05g / L, Ge 4+ 3.48g / L, CL - 47.4g / L, tartaric acid 124.9g / L, germanium hydrolysis precipitation rate 59.25%, tartaric acid precipitation rate 12.66%. Combine the two hydrolysis filter cakes 327.6g, add 1.0L of new water to mix, stir and wash at 75℃ for 1.0 hour, vacuum filter to get 262.4g of washing filter cake, dry at 250℃ to get 131.2g of germanium concentrate, containing 11.23% germanium, equivalent to 14.73g of germanium metal, washing filtrate 1.0L, containing Ge 4+0.14g / L, tartaric acid 2.34g / L, germanium elution rate 0.94%, tartaric acid elution rate 12.93%. The cumulative germanium hydrolysis precipitation rate is 80.82%, tartaric acid recovery rate is 88.98%, and the unit consumption of germanium metal sodium hydroxide for germanium concentrate is 25.55gNaOH / gGe.

[0052] Embodiment 1:

[0053] The molar concentration of germanium in the purified solution is 0.0165 mol / L. The organic phase containing trioctyl decyl alkyl tertiary amine is prepared according to the molar concentration of the extractant trioctyl decyl alkyl tertiary amine in the organic phase and the molar concentration of germanium in the feed solution at a ratio of 22:1. The newly prepared organic phase is mixed with 100g / L sulfuric acid solution at a ratio of Vo / Va=2:1 for 10 minutes, and the layers are allowed to stand to obtain the upper acidified organic phase and the acidified liquid. The loaded organic phase contains 35.2g / L of hydrogen sulfate ions.

[0054] Take 10.0L of the purified liquid and dechlorinate it with a macroporous strong base ion exchange resin to obtain the adsorbed liquid containing Cl - 0.19g / L. Add 72.0g of tartaric acid to the adsorption liquid and mix well to obtain a sulfate solution containing germanium tartaric acid complex, i.e., the feed liquid, which is extracted with 5.0L of acidified organic phase in a small three-stage countercurrent mixer-clarifier, with a ratio of Vo / Va=1:2, a temperature of 30℃~35℃, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a raffinate containing Zn 2+ 110.2g / L, Mn 2+ 21.1g / L, Fe 3+ 0.020g / L, Fe 2+ 3.25g / L, Cd 2+ 2.78g / L, Ge 4+ 0.005g / L, Ni 2+ 0.045g / L, Co 2+ 0.008g / L, Cu 2+ Not detected, F - 0.080g / L, CL - Not detected, T AS 0.12g / L, Sb 0.010g / L, SiO20.045g / L, H2SO422.80g / L, tartaric acid 0.010g / L, the extraction rates of zinc, cadmium, germanium, chlorine and tartaric acid were 0.27%, 15.24%, 99.58%, 100% and 99.86% respectively, and the concentrations of zinc, cadmium, germanium, chlorine, hydrogen sulfate ion and tartaric acid in the loaded organic phase were 0.6g / L, 1.0g / L, 2.39g / L, 0.4g / L, 25.2g / L and 14.38g / L respectively.

[0055] Embodiment 2:

[0056] The molar concentration of germanium in the purified liquid is 0.0165 mol / L, and the organic phase containing trioctyl decyl alkyl tertiary amine is prepared according to the molar concentration of the extractant trioctyl decyl alkyl tertiary amine in the organic phase and the molar concentration of germanium in the feed liquid of 24:1. Example 1 The acidified liquid is supplemented with sulfuric acid to contain 100 g / L of free sulfuric acid, and mixed with the newly prepared organic phase at a ratio of Vo / Va=2:1 for 10 minutes, and allowed to stand for stratification to obtain the upper acidified organic phase and the acidified liquid, and the loaded organic phase contains 38.4 g / L of hydrogen sulfate ions.

[0057] Take 10.0L of the purified liquid and extract it with an amine extractant solvent to remove chlorine. The residual liquid contains Cl - 0.16g / L. Add 72.0g of tartaric acid to the residual liquid and mix well to obtain a sulfate solution containing germanium tartaric acid complex, i.e., the feed liquid, which is extracted with 5.0L of acidified organic phase in a small three-stage countercurrent mixer-settler, with a ratio of Vo / Va=1:2, a temperature of 30℃~35℃, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a residual liquid containing Zn 2+ 110.2g / L, Mn 2+ 21.1g / L, Fe 3+ 0.020g / L, Fe 2+ 3.25g / L, Cd 2+ 2.78g / L, Ge 4+ 0.002g / L, Ni 2+ 0.045g / L, Co 2+ 0.008g / L, Cu 2+ Not detected, F - 0.080g / L, CL - Not detected, T AS 0.12g / L, Sb 0.010g / L, SiO20.045g / L, H2SO424.10g / L, tartaric acid 0.010g / L, the extraction rates of zinc, cadmium, germanium, chlorine and tartaric acid were 0.27%, 15.24%, 99.83%, 100% and 99.86% respectively, and the concentrations of zinc, cadmium, germanium, chlorine, hydrogen sulfate ion and tartaric acid in the loaded organic phase were 0.6g / L, 1.0g / L, 2.40g / L, 0.32g / L, 25.8g / L and 14.38g / L respectively.

[0058] Embodiment 3:

[0059] Example 1 and Example 2 were combined to obtain a mixed load organic phase of 10.0 L, containing zinc, cadmium, germanium, chlorine, hydrogen sulfate ion and tartaric acid concentrations of 0.6 g / L, 1.0 g / L, 2.40 g / L, 0.36 g / L, 25.50 g / L and 14.38 g / L, respectively, and extracted with 5.0 L 40.0 g / L tartaric acid solution in a small secondary countercurrent mixer-clarifier, compared with Vo / Va = 2: 1, temperature 30 ° C ~ 35 ° C, mixing time 10 minutes, standing for 10 minutes, to obtain wash water containing Zn 2+ 0.72g / L, Cd 2+ 0.07g / L, Ge 4+ 0.015g / L, CL - 0.36g / L, H2SO43.26g / L, tartaric acid 41.26g / L, the elution rates of zinc, cadmium, germanium, chlorine and hydrogen sulfate ions were 60.0%, 3.50%, 0.31%, 50.0% and 6.39%, respectively, and the concentrations of zinc, cadmium, germanium, chlorine, hydrogen sulfate ions and tartaric acid in the loaded organic phase were 0.24g / L, 0.965g / L, 2.39g / L, 0.18g / L, 23.87g / L and 13.75g / L, respectively.

[0060] 2.0L of the washed load organic phase was mixed with 0.4L 80.0g / L sodium hydroxide solution for back extraction, and the organic phase was directly hydrolyzed, with a ratio of Vo / Va=5:1, a temperature of 30℃~35℃, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a back extraction solution, which was a suspension with precipitation, containing 5.38g / L germanium, 5.0g / L free sodium hydroxide, and 61.88g / L tartaric acid. The first back extraction organic phase was mixed with 0.4L 80.0g / L sodium hydroxide solution for back extraction, and the organic phase was regenerated, with a ratio of Vo / Va=5:1, a temperature of 30℃~35℃, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a secondary back extraction solution and an empty organic phase, and the secondary back extraction solution was a clear solution, containing 0.75g / L germanium, 78.4g / L free sodium hydroxide, and 6.86g / L tartaric acid. The operation was repeated, and 10 L of the organic phase was washed to obtain 2.0 L of a primary stripping suspension and 0.4 L of a secondary stripping solution. The primary stripping solution consumed 160.0 g of sodium hydroxide and recovered 134.8 g of tartaric acid, with a recovery rate of 98.04%.

[0061] Take 2.0L of the primary stripping suspension, add the acidified solution of Example 2 under stirring to adjust the pH to 9.0, heat to 75°C, add 53.8g of magnesium sulfate heptahydrate according to 5 times the amount of germanium, keep warm for 1.5 hours, vacuum filter to obtain 215.6g of hydrolysis filter cake, 2.0L of hydrolysis filtrate, containing 2.38g / L of germanium and 51.2g / L of tartaric acid. Add 1.0L of new water to the hydrolysis filter cake, stir and wash at 75°C for 1.0 hour, vacuum filter to obtain 188.2g of water-washed filter cake, 1.0L of washing water, containing 0.45g / L of germanium and 7.5g / L of tartaric acid.

[0062] The washed filter cake was dried at 250°C to obtain 74.56g of milky white powder, containing 24.66% germanium, equivalent to 18.39g of germanium metal. Based on the amount of germanium loaded in the organic phase, the direct recovery rate of germanium metal in the germanium concentrate was 76.65%, and the unit consumption of sodium hydroxide for germanium metal in the germanium concentrate was 8.70g / g.

[0063] Embodiment 4:

[0064] Take the empty organic phase containing the extractant octyl decyl alkyl tertiary amine of Example 3, the molar concentration of germanium in the purified liquid is 0.0165 mol / L, and the molar concentration of the extractant trioctyl decyl alkyl tertiary amine in the organic phase is 23:1 to the molar concentration of germanium in the feed liquid. The acidified liquid of Example 2 is adjusted with sulfuric acid to a 100 g / L sulfuric acid solution, and mixed with the empty organic phase at a ratio of Vo / Va=2:1 for 10 minutes, and allowed to stand for stratification to obtain an upper acidified organic phase, and the loaded organic phase contains 36.8 g / L of hydrogen sulfate ions.

[0065] Take 20.0L of the purified liquid and dechlorinate it by cuprous salt precipitation method to obtain the dechlorinated liquid, which contains Cl - 0.18g / L. Add 144.0g of tartaric acid to the dechlorinated liquid and mix well to obtain a sulfate solution containing germanium tartaric acid complex, i.e., the feed liquid, and extract it with 10.0L of acidified organic phase in a small three-stage countercurrent mixer-settler, with a ratio of Vo / Va=1:2, a temperature of 30℃~35℃, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a primary raffinate containing Zn 2+ 110.2g / L, Mn 2+ 21.1g / L, Fe 3+ 0.020g / L, Fe 2+ 3.25g / L, Cd 2+ 2.78g / L, Ge 4+ 0.005g / L, Ni 2+ 0.045g / L, Co 2+ 0.008g / L, Cu 2+ Not detected, F - 0.080g / L, CL - Not detected, T AS0.12g / L, Sb 0.010g / L, SiO20.045g / L, H2SO423.50g / L, tartaric acid 0.010g / L, the extraction rates of zinc, cadmium, germanium, chlorine and tartaric acid were 0.27%, 15.24%, 99.58%, 100% and 99.86% respectively, and the concentrations of zinc, cadmium, germanium, chlorine, hydrogen sulfate ion and tartaric acid in the primary load organic phase were 0.6g / L, 1.0g / L, 2.39g / L, 0.4g / L, 25.4g / L and 14.38g / L respectively.

[0066] The hydrolysis filtrate and washing water of Example 3 were combined to obtain a mixed solution of 3.0 L, containing 1.737 g / L germanium and 36.63 g / L tartaric acid, and then subjected to secondary extraction with 10.0 L of the primary loaded organic phase in a small secondary countercurrent mixer-settler, with a ratio of Vo / Va=10:3, a temperature of 30°C to 35°C, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a secondary raffinate containing Ge. 4+ 0.12g / L, tartaric acid 31.46g / L, the extraction rates of germanium and tartaric acid were 93.09% and 14.11%, respectively, and the concentrations of germanium and tartaric acid in the secondary load organic phase were 2.93g / L and 16.10g / L, respectively.

[0067] 2.0L of the secondary loaded organic phase was mixed with 0.4L 80.0g / L sodium hydroxide solution for stripping, and the organic phase was directly hydrolyzed, with a ratio of Vo / Va=5:1, a temperature of 30℃~35℃, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a stripping solution, which was a suspension with precipitation, containing 5.18g / L germanium, 2.0g / L free sodium hydroxide, and 73.82g / L tartaric acid. The primary stripping organic phase was mixed with 0.4L 80.0g / L sodium hydroxide solution for stripping, and the organic phase was regenerated, with a ratio of Vo / Va=5:1, a temperature of 30℃~35℃, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a secondary stripping solution and an empty organic phase, and the secondary stripping solution was a clear solution, containing 0.68g / L germanium, 78.2g / L free sodium hydroxide, and 6.66g / L tartaric acid. The operation was repeated, and 10 L of the organic phase was washed to obtain 2.0 L of a primary stripping suspension and 0.4 L of a secondary stripping solution. The primary stripping solution consumed 160.0 g of sodium hydroxide and recovered 158.3 g of tartaric acid, with a recovery rate of 98.32%.

[0068] Take 2.0L of the primary stripping suspension, add the acidified solution under stirring to adjust the pH to 9.0, heat to 75°C, add 36.3g of magnesium sulfate heptahydrate according to 7 times the amount of germanium, keep warm for 1.5 hours, vacuum filter, get 262.3g of hydrolysis filter cake, get 2.0L of hydrolysis filtrate, containing 2.48g / L of germanium and 54.41g / L of tartaric acid. Add 1.0L of new water to the hydrolysis filter cake, stir and wash at 75°C for 1.0 hour, vacuum filter, get 209.5g of water-washed filter cake, get 1.0L of washing water, containing 0.52g / L of germanium and 8.34g / L of tartaric acid.

[0069] The washed filter cake was dried at 300°C to obtain 94.41g of milky white powder, containing 25.23% germanium, equivalent to 23.82g of germanium metal. Based on the amount of germanium loaded in the organic phase, the direct recovery rate of germanium metal in the germanium concentrate was 81.30%, and the unit consumption of sodium hydroxide for germanium metal in the germanium concentrate was 6.72g / g.

[0070] Embodiment 5:

[0071] Take the empty organic phase containing the extractant octyl decyl alkyl tertiary amine of Example 4, the molar concentration of germanium in the purified liquid is 0.0165 mol / L, and the molar concentration of the extractant trioctyl decyl alkyl tertiary amine in the organic phase is 23:1 to the molar concentration of germanium in the feed liquid. The acidified liquid of Example 4 is adjusted with sulfuric acid to a 100 g / L sulfuric acid solution, and mixed with the empty organic phase at a ratio of Vo / Va=2:1 for 10 minutes, and allowed to stand for stratification to obtain an upper acidified organic phase, and the loaded organic phase contains 36.8 g / L of hydrogen sulfate ions.

[0072] Take 20.0L of the purified liquid and dechlorinate it by cuprous salt precipitation method to obtain the dechlorinated liquid, which contains Cl - The dechlorinated liquid was mixed with the secondary raffinate of Example 4, 51.8 g of tartaric acid was added, and mixed evenly to obtain a sulfate solution containing germanium tartaric acid complex, i.e., the feed liquid, and extracted once with 10.0 L of acidified organic phase in a small three-stage countercurrent mixer-settler, with a ratio of Vo / Va=1:2, a temperature of 30°C to 35°C, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a primary raffinate containing Ge. 4+ The extraction rates of germanium and tartaric acid were 99.52% and 99.84% respectively. The concentrations of germanium and tartaric acid in the organic phase were 2.42g / L and 14.59g / L respectively.

[0073] The hydrolysis filtrate and washing water of Example 4 were combined to obtain a mixed solution of 3.0 L, containing 1.827 g / L germanium and 39.05 g / L tartaric acid, and a secondary extraction was performed with 10.0 L of the primary load organic phase in a small secondary countercurrent mixer-settler, with a ratio of Vo / Va=10:3, a temperature of 30°C to 35°C, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a secondary raffinate containing Ge 4+0.15g / L, tartaric acid 32.33g / L, the extraction rates of germanium and tartaric acid were 91.79% and 17.21%, respectively, and the concentrations of germanium and tartaric acid in the secondary load organic phase were 2.97g / L and 16.61g / L, respectively.

[0074] 2.0L of the secondary loaded organic phase was mixed with 0.4L of 80.0g / L sodium hydroxide solution for stripping, and the organic phase was directly hydrolyzed, with a ratio of Vo / Va=5:1, a temperature of 30℃~35℃, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a stripping solution, which was a suspension with precipitation, containing 5.15g / L germanium, 3.0g / L free sodium hydroxide, and 73.62g / L tartaric acid. The organic phase of the primary stripping was mixed with 0.4L of 80.0g / L sodium hydroxide solution for stripping, and the organic phase was regenerated, with a ratio of Vo / Va=5:1, a temperature of 30℃~35℃, a mixing time of 10 minutes, and a standing time of 10 minutes to obtain a secondary stripping solution and an empty organic phase, and the secondary stripping solution was a clear solution, containing 0.63g / L germanium, 78.5g / L free sodium hydroxide, and 9.42g / L tartaric acid. The operation was repeated, and 10 L of the organic phase was washed to obtain 2.0 L of a primary stripping suspension and 0.4 L of a secondary stripping solution. The primary stripping solution consumed 160.0 g of sodium hydroxide and recovered 162.3 g of tartaric acid, with a recovery rate of 97.71%.

[0075] Take 2.0L of the primary stripping suspension, add the acidified solution under stirring to adjust the pH to 9.0, heat to 75°C, add 31.0g of magnesium sulfate heptahydrate according to 6 times the amount of germanium, keep warm for 1.5 hours, vacuum filter, get 261.5g of hydrolysis filter cake, get 2.0L of hydrolysis filtrate, containing 2.43g / L of germanium and 58.46g / L of tartaric acid. Add 2.0L of new water to the hydrolysis filter cake, stir and wash at 75°C for 1.0 hour, vacuum filter, get 209.3g of water-washed filter cake, get 2.0L of washing water, containing 0.22g / L of germanium and 8.54g / L of tartaric acid.

[0076] The washed filter cake was dried at 280°C to obtain 94.30 g of milky white powder containing 25.43% germanium, equivalent to 23.98 g of germanium metal.

[0077] The implementation results are shown in Table 1 and Table 2. It can be seen that the recovery rate of germanium metal in germanium concentrate is 99.92% based on the amount of germanium metal in the liquid; the unit consumption of tartaric acid of germanium metal in germanium concentrate is 1.35g / g; and the unit consumption of sodium hydroxide of germanium metal in germanium concentrate is 6.67g.

[0078] Table 1 Germanium metal statistical balance sheet

[0079]

[0080] Table 2 Statistical balance of tartaric acid

[0081]

Claims

1. A method for extracting germanium by solvent and preparing germanium concentrate, characterized in that: The following steps are included: A) mixing the feed liquid, the secondary raffinate and the acidified organic phase, and performing a primary extraction to produce a primary raffinate and a primary loaded organic phase, wherein the feed liquid is a sulfate solution containing germanium tartaric acid complex, the secondary raffinate contains tartaric acid as a complexing agent, the acidified organic phase contains trioctyldecyl tertiary amine as an extractant, and the primary raffinate is used for recycling other metals; B) mixing the primary loaded organic phase, the hydrolyzed liquid and the washing water phase produced in step A, and performing secondary extraction to produce a secondary raffinate and a secondary loaded organic phase, wherein the hydrolyzed liquid and the washing water contain tartaric acid as a complexing agent, and the secondary raffinate is returned to step A for use; C) mixing the secondary loaded organic phase produced in step B with a sodium hydroxide solution, and performing stripping to produce an empty organic phase and a stripping solution; D) mixing the empty organic phase, sulfuric acid solution and / or acidified liquid produced in step C, performing acidification transformation, and producing an acidified organic phase and an acidified liquid, wherein the acidified organic phase is returned to step A for use, and part of the acidified liquid is returned to this step for use; E) The stripping solution produced in step C, the partially acidified solution produced in step D, and magnesium sulfate heptahydrate are mixed and hydrolyzed to produce a hydrolyzed solution and a hydrolysis filter cake. The hydrolysis filter cake is washed with fresh water to produce a washing filter cake and washing water. The hydrolyzed solution and washing water contain tartaric acid as a complexing agent and are returned to step B for use. The washing filter cake is dried to produce a germanium concentrate.

2. The method for extracting germanium by solvent and preparing germanium concentrate according to claim 1, characterized in that: In step A, the feed solution is pretreated with dechlorination, and the mass volume concentration of chloride ions is less than 0.2 g / L.

3. A method for extracting germanium with solvent and preparing germanium concentrate according to claim 1 or 2, characterized in that: In step A, the ratio of the molar concentration of the extractant trioctyl decyl alkyl tertiary amine in the acidified organic phase to the molar concentration of germanium in the feed solution is 22-24:

1.

4. The method for extracting germanium by solvent and preparing germanium concentrate according to claim 3, characterized in that: The stripping in step C is a two-stage countercurrent stripping, the secondary loaded organic phase is mixed with the secondary stripping solution for primary stripping, and the primary stripping solution is produced as the stripping solution, which contains 2.0 g / L to 5.0 g / L of free sodium hydroxide. The primary stripping organic phase is mixed with the sodium hydroxide solution for secondary stripping, and the secondary stripping organic phase is an empty organic phase.

5. The method for extracting germanium by solvent and preparing germanium concentrate according to claim 4, characterized in that: In the hydrolysis of step E, firstly, part of the acidified solution produced in step D is added to the stripping solution produced in step C, the pH is adjusted to 9-10, and then magnesium sulfate is added at 5-7 times the weight of germanium in the solution, and mixed and hydrolyzed.

6. The method for extracting germanium by solvent and preparing germanium concentrate according to claim 5, characterized in that: The drying temperature of the washed filter cake in step E is 250°C to 300°C.

7. The method for extracting germanium by solvent and preparing germanium concentrate according to claim 1, characterized in that: The phase ratio of the secondary extraction in step B is Vo / Va = 10:3-4.

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