A method for recovering dispersed metals from industrial waste water

Abstract

This invention discloses a method for recovering rare and dispersed metals from industrial wastewater, belonging to the field of wastewater treatment technology. The method includes selectively adsorbing rhenium from the industrial wastewater; co-extracting indium and molybdenum in the adsorbed liquid using a first organic phase including P2O4, followed by a staged back-extraction process involving indium back-extraction, iron washing, and molybdenum back-extraction to regenerate and recycle the first organic phase; and then selectively extracting germanium using a second organic phase including N235 and TBP after complexation pretreatment of the raffinate. This invention, through a unique process combination and synergistic effect, solves the problems of poor selectivity, easy poisoning of organic phases, and low recovery rate in complex multi-metal systems, achieving efficient separation, recovery, and high-value utilization of rhenium, indium, molybdenum, and germanium.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, and in particular to a method for recovering rare and dispersed metals from industrial wastewater. Background Technology

[0002] Rhenium, indium, molybdenum, and germanium are scarce and high-value rare dispersed metals widely used in strategic fields such as aerospace, semiconductors, and new energy. Their efficient recycling and resource utilization are of great significance for ensuring the security of the industrial chain. In industrial production, polymetallic wastewater containing rhenium, indium, molybdenum, and germanium (such as the liquid after the reduction of white dust from copper smelting) has a complex composition and is often accompanied by high concentrations of impurities such as iron, zinc, arsenic, and cadmium. Traditional recycling processes suffer from problems such as fragmented processes, low resource utilization, and poor organic phase reuse performance, which restrict large-scale application.

[0003] In existing processes, rhenium recovery largely relies on ion exchange methods. However, the resin's selectivity for rhenium is insufficient, and it is easily interfered with by other anions (such as molybdate and chloride ions), resulting in low adsorption capacity, difficult desorption, and rapid performance degradation after resin regeneration, making long-term stable operation difficult. For indium and molybdenum recovery, solvent extraction is commonly used. Acidic extractants such as P204 have a strong affinity for indium and also exhibit high extraction rates for molybdenum in strongly acidic sulfuric acid systems (achieving indium-molybdenum co-extraction). However, the molybdenum-indium co-extraction of P204 is susceptible to Fe... 3+ / Fe 2+ The competitive impact of iron removal is significant. Without deep purification of the supported organic phase, iron gradually accumulates, occupying effective extraction sites and causing a significant decrease in the extraction rate of indium from the organic phase with increasing organic phase reuse frequency (experimental results show that without iron removal from the organic phase, the indium extraction rate drops from 98.8% to 74.1% after 3-4 reuses). Furthermore, iron accumulation increases the viscosity of the organic phase, slows phase separation, and may even trigger emulsification, further affecting process stability. Therefore, iron removal from the supported organic phase is necessary. Traditional iron removal methods involve using sulfuric acid or hydrochloric acid for iron back-extraction. However, the back-extraction kinetics of sulfuric acid are slower than those of hydrochloric acid. To achieve the same back-extraction rate, sulfuric acid requires higher acidity, longer reaction time, or more stages, leading to larger reaction vessels or reduced production efficiency. Therefore, using hydrochloric acid for iron back-extraction is a good method. In fact, hydrochloric acid as an iron back-extraction agent requires a high concentration, typically above 6 mol / L. However, high-concentration hydrochloric acid is highly corrosive, placing high demands on equipment and potentially degrading the organic phase, leading to a drastic reduction in its lifespan. Traditional germanium recovery processes (such as direct precipitation and single-extractant methods) face several bottlenecks when processing complex systems with low-concentration germanium (70-90 mg / L) and high concentrations of zinc, iron, and arsenic: one bottleneck is the complex morphology of germanium in the reduced solution (e.g., Ge...). 4+ GeO32- Secondly, high concentrations of impurity ions (such as Fe2+, complexed ions, etc.) are difficult to accurately identify with a single extractant; and thirdly, high concentrations of impurity ions (such as Fe2+, complexed ions, etc.) are difficult to identify accurately with a single extractant. 3+ Zn 2+ First, the extraction rate is generally lower than 60% because the extractant competes with germanium for binding sites. Second, the amine extractant used in traditional technology (such as N235) has low interfacial tension and polarity mismatch with the aqueous phase, which makes it easy to generate a third phase or emulsion, making phase separation difficult, especially in high acidity and high salt systems.

[0004] Therefore, how to efficiently recover rare and dispersed metals from industrial wastewater containing rhenium, indium, molybdenum, germanium, and impurity ions such as iron and zinc ions is one of the key research topics in this field. Summary of the Invention

[0005] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes a method for recovering rare and dispersed metals from industrial wastewater, which can achieve the separate recovery of Re, Mo, In and Ge, obtain high-value, high-purity products, and improve the ability to resist impurity interference during the recovery process.

[0006] According to an embodiment of a first aspect of the present invention, a method for recovering rare and dispersed metals from industrial wastewater is provided, the industrial wastewater containing ionic rare and dispersed metals and impurities; the rare and dispersed metals include Re, Mo, In, and Ge; the impurities include Fe; The method includes the following steps: S1. The industrial wastewater is adsorbed with resin to obtain a loaded resin and an adsorbed liquid; the loaded resin is desorbed with ammonia to obtain a rhenium-rich solution; the resin is a macroporous weakly basic anion exchange resin; the adsorption flow rate is 4~6 BV / h; the desorption flow rate is 1~3 BV / h. S2. Extract the adsorbed liquid with a first organic phase to obtain a loaded organic phase and a raffinate; the first organic phase includes P2O4; S3. The supported organic phase is back-extracted using the first back-extracting agent to obtain an indium-rich solution and the remaining organic phase; The remaining organic phase is washed with a detergent to remove iron, resulting in an iron-free organic phase; the detergent includes ascorbic acid and hydrochloric acid; The iron-removed organic phase is back-extracted using a second back-extracting agent to obtain a molybdenum-rich solution; S4. The organic acid and the raffinate are mixed and reacted to obtain a germanium-containing solution; in the mixed system of organic acid and raffinate, the concentration of the organic acid is 650~1000 mg / L; The germanium-containing feed solution was extracted using a second organic phase to obtain a germanium-supported organic phase; the second organic phase comprised N235 and TBP. The germanium-supported organic phase was back-extracted to obtain a germanium-rich solution.

[0007] The method according to embodiments of the present invention has at least the following beneficial effects: The use of detergent in step S3 significantly improves the method's resistance to impurity interference: Studies have found that P204 extractant has a significant effect on Fe. 3+ Its extraction performance is far superior to Fe 2+ Based on the extraction mechanism analysis, P204 has a significant effect on Fe. 2+ The back-extraction performance will be much higher than that of Fe. 3+ Therefore, this invention innovatively utilizes a mild and inexpensive reducing agent—ascorbic acid—to construct a hydrochloric acid-ascorbic acid composite detergent system. This system effectively removes difficult-to-extract Fe... 3+ Reduced to Fe 2+ Furthermore, it can precisely capture iron ions in the aqueous phase through complexation, and the dual-drive back-extraction balance shifts to the right, which increases the iron back-extraction rate from the traditional 80-90% to 95-99%. On the other hand, the introduction of ascorbic acid reduces the requirement for hydrochloric acid concentration and effectively prevents high-concentration hydrochloric acid from corroding the equipment.

[0008] The back-extraction of molybdenum in step S3 significantly reduces the consumption of the first organic phase: This invention adds a molybdenum back-extraction step, which on the one hand enables the recovery of molybdenum resources to generate revenue, and on the other hand removes elements from the organic phase (first organic phase) as deeply as possible to avoid their accumulation in the organic phase and causing aging. Simultaneously, the method provided by this invention establishes a closed-loop system of "indium extraction-indium back-extraction-iron back-extraction-molybdenum back-extraction-reuse," significantly reducing extractant consumption, lowering operating costs, and reducing the environmental pressure caused by wastewater discharge.

[0009] The special design in step S4 significantly improves the resistance to interference from impurity ions during the germanium recovery process: This invention introduces organic acids as specific complexing agents to pretreat the raffinate, allowing the organic acids to react with Ge. 4+ A stable complex is formed, which has a specific spatial structure and can be precisely captured by N235 through ion association. In contrast, the complexes formed by impurity ions such as iron, zinc, and cadmium with organic acids have extremely low stability and cannot be effectively extracted by N235. This allows for the efficient separation of germanium from other impurity cations.

[0010] Furthermore, when traditional amine extractants (such as N235) are used alone, they can generate a third phase or emulsify due to problems such as low interfacial tension with the aqueous phase and polarity mismatch, making phase separation difficult, especially in high acidity and high salt systems. This invention uses tributyl phosphate (TBP) as a co-extractant, which reduces the interfacial tension between N235 and the aqueous phase by adjusting the polarity of the organic phase, thus avoiding the formation of a third phase.

[0011] The parameter settings performed in the method significantly improve the recovery effect of the rare dispersed metals: In step S1, the restrictions on adsorption and desorption parameters improve the adsorption and desorption rates of rhenium, thus improving the overall rhenium recovery rate. Specifically, if the over-adsorption flow rate exceeds the range required by this invention, the breakthrough adsorption capacity of the resin will decrease (e.g., increasing the flow rate to 8 Bv / h results in a breakthrough adsorption capacity of 10 g / L, while at a flow rate of 4 Bv / h, the breakthrough adsorption capacity is 12 g / L). Within the aforementioned flow rate range, production efficiency is ensured. The same applies to the desorption flow rate; if the flow rate is too high, the desorption rate decreases.

[0012] In step S4, limiting the concentration of organic acid significantly improves the extraction rate of germanium and increases the purity of the germanium-containing product recovered from the germanium-rich solution; it also avoids the waste of organic acid.

[0013] In the method described above, the extraction sequence plays a significant role in the successful recovery of rare and dispersed metals. Recovering rhenium first will not affect indium, molybdenum, and germanium, as the concentrations of these three rare metals remain almost unchanged before and after adsorption. This ensures efficient separation of rhenium from indium, molybdenum, and germanium. At the same time, no new reagents are introduced during the adsorption of rhenium, avoiding the influence of new reagents on the subsequent separation process. If the order is reversed and indium, molybdenum, and germanium are recovered first by extraction, the oil phase in the raffinate will increase. When rhenium is recovered by ion exchange later, the organic phase will enter the resin and adhere to its surface, causing a decrease in the resin's adsorption performance. Alternatively, an oil removal device must be added to solve the above problems. Indium-molybdenum extraction must precede germanium extraction for two reasons. First, co-extraction of indium and molybdenum does not affect the germanium content in the raffinate (germanium is almost not extracted). However, if germanium extraction is performed first, the N235 and TBP co-extraction system has some extraction performance for indium and molybdenum, which will affect the separation of indium, molybdenum, and germanium. Second, since tartaric acid is added during germanium extraction, a certain amount of tartaric acid molecules will remain in the raffinate after germanium extraction. If germanium is extracted first, the tartaric acid in the raffinate may affect the extraction of indium and molybdenum. Therefore, the extraction process of rhenium, indium, molybdenum, and germanium should proceed from simple to complex, and the order cannot be reversed; if reversed, the function of separate recovery of rare and dispersed metals may be lost.

[0014] In summary, this invention, through a unique combination of processes and synergistic effects, solves the problems of poor selectivity, easy poisoning of organic phases, and low recovery rate in complex multi-metal systems. It achieves efficient separation, recovery, and high-value utilization of rhenium, indium, molybdenum, and germanium; the target metals have high recovery rates and high purity; and it does not affect subsequent wastewater treatment processes. It achieves environmental protection while greatly increasing resource recovery efforts, contributing to sustainable development.

[0015] According to some embodiments of the present invention, the concentration of the rare and dispersed metals and impurities in the industrial wastewater is: Re30~37mg / L; for example, it can be 30mg / L, 32mg / L, 34mg / L, 36mg / L; or a range of values ​​consisting of any two of the above points.

[0016] Mo 315~513 mg / L; for example, it can be 315 mg / L, 320 mg / L, 330 mg / L, 340 mg / L, 350 mg / L, 360 mg / L, 370 mg / L, 380 mg / L, 390 mg / L, 400 mg / L, 420 mg / L, 440 mg / L, 450 mg / L, 460 mg / L, 480 mg / L, 500 mg / L, 510 mg / L, 512 mg / L; or a range of values ​​consisting of any two of the above points.

[0017] The concentration of 1 is 568~775 mg / L; for example, it can be 568 mg / L, 570 mg / L, 580 mg / L, 600 mg / L, 620 mg / L, 640 mg / L, 660 mg / L, 680 mg / L, 700 mg / L, 720 mg / L, 740 mg / L, 760 mg / L, 775 mg / L; or a range of values ​​consisting of any two of the above points.

[0018] Ge 64~81mg / L; for example, it can be 64mg / L, 65mg / L, 66mg / L, 68mg / L, 70mg / L, 72mg / L, 74mg / L, 76mg / L, 78mg / L, 80mg / L; or a range of values ​​consisting of any two of the above points.

[0019] Fe 12789~16480mg / L. For example, it can be 12789mg / L, 13000mg / L, 13500mg / L, 14000mg / L, 14500mg / L, 15000mg / L, 15500mg / L, 16000mg / L, 16400mg / L, 16480mg / L; or a range of values ​​consisting of any two of the above points.

[0020] According to some embodiments of the present invention, the impurities further include at least one selected from As, Zn, Cd, Bi, Cu, Pb, Al, F, and Cl. Wherein, if the corresponding impurity is present, the impurity content is: As 10784~22824 mg / L; for example, it can be 10784 mg / L, 11000 mg / L, 12000 mg / L, 13000 mg / L, 15000 mg / L, 16000 mg / L, 18000 mg / L, 20000 mg / L, 21000 mg / L, 22000 mg / L, 22824 mg / L; or a range of values ​​consisting of any two of the above points.

[0021] Zn concentrations range from 103261 to 143107 mg / L; specifically, these values ​​could be 103261 mg / L, 105000 mg / L, 110000 mg / L, 120000 mg / L, 130000 mg / L, 140000 mg / L, or 143107 mg / L; or any range consisting of any two of the above values.

[0022] Cd 9872~24813 mg / L; for example, it can be 9872 mg / L, 10000 mg / L, 12000 mg / L, 14000 mg / L, 16000 mg / L, 18000 mg / L, 20000 mg / L, 22000 mg / L, 24000 mg / L, 24813 mg / L; or a range of values ​​consisting of any two of the above points.

[0023] Bi215~723mg / L; for example, it can be 215g / L, 250mg / L, 300mg / L, 350mg / L, 400mg / L, 450mg / L, 500mg / L, 550mg / L, 600mg / L, 650mg / L, 700mg / L, 722mg / L; or a range of values ​​consisting of any two of the above points.

[0024] Cu 42~151 mg / L; for example, it can be 42 mg / L, 45 mg / L, 50 mg / L, 60 mg / L, 80 mg / L, 100 mg / L, 120 mg / L, 140 mg / L, 150 mg / L, 150 mg / L; or a range of values ​​consisting of any two of the above points.

[0025] Pb 9~22 mg / L; for example, it can be 9 mg / L, 10 mg / L, 12 mg / L, 14 mg / L, 16 mg / L, 18 mg / L, 20 mg / L, 21.6 mg / L; or a range of values ​​consisting of any two of the above points.

[0026] Al = 610~675 mg / L; for example, it can be 610 mg / L, 615 mg / L, 620 mg / L, 630 mg / L, 640 mg / L, 650 mg / L, 660 mg / L, 670 mg / L, 674 mg / L; or a range of values ​​consisting of any two of the above points.

[0027] F657~1180mg / L; for example, it can be 657mg / L, 660mg / L, 700mg / L, 800mg / L, 900mg / L, 1000mg / L, 1100mg / L, 1179mg / L; or a range of values ​​consisting of any two of the above points.

[0028] Cl334~501mg / L. For example, it can be 334mg / L, 350mg / L, 400mg / L, 450mg / L, 500mg / L, 500mg / L; or a range of values ​​consisting of any two of the above points.

[0029] According to some embodiments of the present invention, the phenolphthalein acidity of the industrial wastewater is 6.2~6.7 mol / L. Specifically, it can be 6.2 mol / L, 6.3 mol / L, 6.4 mol / L, 6.5 mol / L, 6.6 mol / L; or a range consisting of any two of the above values.

[0030] According to some embodiments of the present invention, the industrial wastewater includes the liquid after reduction of copper smelting white smoke dust.

[0031] According to some embodiments of the present invention, step S1 further includes filtering the industrial wastewater before adsorption. The filter pore size used for filtration is 0.2~0.6μm. Specifically, it can be 0.2μm, 0.22μm, 0.3μm, 0.4μm, 0.45μm, 0.5μm, 0.6μm; or a range of values ​​consisting of any two of the above points.

[0032] Experiments showed that the contents of rhenium, molybdenum, indium, and germanium in the industrial wastewater remained almost unchanged before and after filtration.

[0033] According to some embodiments of the present invention, in step S1, the resin is of type A1701. This resin exhibits extremely high selectivity for rhenium, minimal adsorption of molybdenum, fluorine, and chlorine (adsorption rates all less than 3%), and almost no adsorption of other ions. Using a rhenium concentration of 3 mg / L in the effluent as the breakthrough point, the rhenium adsorption rate reaches 96.1-97.3% after an influent flow rate of 320 Bv, with an adsorption capacity of 8.81-11.27 g / L. The A1701 resin can be reused after regeneration with 5% sulfuric acid. Even after four reuses, the rhenium adsorption-desorption rate remains above 90%. The adsorption rate can specifically be 96.1%, 96.4%, 96.5%, 97%, 97.3%; or a range of values ​​consisting of any two of the above points.

[0034] The adsorption capacity can specifically be 8.81 g / L, 8.9 g / L, 9 g / L, 9.1 g / L, 9.2 g / L, 9.5 g / L, 9.7 g / L, 10 g / L, 10.2 g / L, 10.5 g / L, 10.7 g / L, 11 g / L, or 11.27 g / L; or a range of values ​​consisting of any two of the above points.

[0035] The resolution can specifically be 90%, 91%, 92%, 93%, 93.3%, 94%, 95%, 96%, 96.8%, 97%, 98%, 99%; or a range of values ​​consisting of any two of the above points.

[0036] In some embodiments of the present invention, in step S1, the adsorption flow rate is 4~6 BV / h. For example, it can be 4 BV / h, 4.5 BV / h, 5 BV / h, 5.5 BV / h, 6 BV / h; or a range of values ​​consisting of any two of the above points.

[0037] According to some embodiments of the present invention, in step S1, the desorption flow rate is 1~3 BV / h. For example, it can specifically be 1 BV / h, 1.5 BV / h, 2 BV / h, 2.5 BV / h, 3 BV / h; or a range of values ​​consisting of any two of the above points.

[0038] According to some embodiments of the present invention, in step S1, the mass concentration of the ammonia solution is 3-7%. Specifically, it can be 3%, 4%, 5%, 6%, or 7%; or a range consisting of any two of the above values. Within the above concentration range, as the ammonia concentration increases, the desorption of rhenium initially rises and then stabilizes; and the overall rhenium desorption rate is relatively high. Therefore, within the above concentration range, the rhenium desorption rate can be guaranteed, and the waste of ammonia solution can be avoided.

[0039] When the desorption influent flow rate is 10 Bv, the above-mentioned ammonia concentration can achieve a Re desorption rate of 93.3-96.8%.

[0040] According to some embodiments of the present invention, in step S1, the rhenium concentration in the rhenium-rich solution is 2.76~3.48 g / L. For example, it can specifically be 2.76 g / L, 2.8 g / L, 3.0 g / L, 3.2 g / L, 3.4 g / L, 3.48 g / L; or a range of values ​​consisting of any two of the above points.

[0041] According to some embodiments of the present invention, the method further includes crystallizing ammonium perrhenate from the rhenium-rich solution. The crystallization process includes evaporation crystallization and recrystallization.

[0042] The purity of the obtained ammonium perrhenate is ≥99.99%; for example, it can be 99.991%, 99.992%, 99.993%, 99.994%; or a range of values ​​consisting of any two of the above points.

[0043] The evaporation temperature during evaporation crystallization is 80~90℃; for example, it can be 80℃, 82℃, 84℃, 85℃, 86℃, 88℃, 90℃; or any range of two of the above points; the cooling temperature during evaporation crystallization is 0~5℃.

[0044] According to some embodiments of the present invention, in step S2, the indium content in the post-adsorption solution is 568.7~775 mg / L. Specifically, it can be 568.7 mg / L, 600 mg / L, 620 mg / L, 640 mg / L, 660 mg / L, 680 mg / L, 700 mg / L, 720 mg / L, 740 mg / L, 760 mg / L, 770 mg / L, or 775 mg / L; or a range consisting of any two of the above values.

[0045] According to some embodiments of the present invention, in step S2, the molybdenum content in the post-adsorption solution is 315~512.4 mg / L. Specifically, it can be 315 mg / L, 320 mg / L, 350 mg / L, 370 mg / L, 400 mg / L, 420 mg / L, 450 mg / L, 470 mg / L, 500 mg / L, or 512.4 mg / L; or a range consisting of any two of the above values.

[0046] According to some embodiments of the present invention, in step S2, the volume percentage of P2O4 in the first organic phase is 30-40%. For example, it can be 30%, 32%, 34%, 36%, 38%, 40%; or a range of values ​​composed of any two of the above points.

[0047] According to some embodiments of the present invention, in step S2, the first organic phase further includes a diluent. The diluent includes sulfonated kerosene. The amount of sulfonated kerosene used is the remainder of the P204.

[0048] According to some embodiments of the present invention, in step S2, the O / A ratio of the extraction is 1:6 to 10. For example, it can be 1:6, 1:7, 1:8, 1:9, 1:10; or a range of values ​​composed of any two of the above points.

[0049] Within this range, the co-extraction rate of molybdenum and indium is significantly improved, and emulsification caused by excessive first organic phase can be avoided, thus extending the cycle life of the first organic phase.

[0050] According to some embodiments of the present invention, in step S2, the number of extraction stages is 2 to 3.

[0051] According to some embodiments of the present invention, in step S2, the extraction method is cross-flow extraction.

[0052] According to some embodiments of the present invention, in step S2, the extraction rate of indium is 98.8% to 99.4%. For example, it can be 98.8%, 99%, 99.2%, 99.4%; or a range of values ​​consisting of any two of the above points.

[0053] According to some embodiments of the present invention, in step S2, the extraction rate of molybdenum is 97.5% to 98.7%. For example, it can be 97.5%, 98%, 98.5%, 98.6%, 98.7%; or a range of values ​​consisting of any two of the above points.

[0054] In step S2, molybdenum and indium co-extraction was achieved by adjusting the parameters appropriately and considering the composition of the first organic phase.

[0055] According to some embodiments of the present invention, step S3 further includes back-extraction with the first back-extracting agent and water washing after the washing. The O / A ratio of the water wash is 1:5; the number of water washing stages is 1 to 3. This removes the adsorbed liquid or detergent entrained in the supported organic phase. Simultaneously, ensuring this O / A ratio also avoids density increase caused by excessive moisture in the organic phase; that is, controlling this ratio improves the cycle life of the first organic phase.

[0056] According to some embodiments of the present invention, in step S3, the first stripping agent is hydrochloric acid at a concentration of 3.5 to 4.5 mol / L. Specifically, it can be 3.5 mol / L, 4 mol / L, or 4.5 mol / L; or a range consisting of any two of the above values.

[0057] This maximizes the indium back-extraction rate while minimizing iron back-extraction, thus improving the purity of the resulting sponge indium.

[0058] According to some embodiments of the present invention, in step S3, the back-extraction is performed using the first back-extraction agent, with an O / A ratio of 5 to 10:1; specifically, it can be 5:1, 8:1, 10:1; or a range of values ​​composed of any two of the above points. Further, the back-extraction method is cross-flow back-extraction; the number of back-extraction stages is 3 to 5.

[0059] According to some embodiments of the present invention, in step S3, the indium back-extraction rate is 99.6% to 99.89%. For example, it can specifically be 99.6%, 99.7%, 99.8%, 99.89%; or a range of values ​​consisting of any two of the above points.

[0060] Simultaneously, it may remove some of the iron in the supported organic phase, with an iron removal rate of 9.5% to 13%. For example, it could be 9.5%, 10%, 10.5%, 11%, 11.5%, 12%, 12.5%, or 13%; or a range of values ​​consisting of any two of the above points.

[0061] According to some embodiments of the present invention, the concentration of indium in the indium-rich solution is 22.5~30.3 g / L. For example, it can be 22.5 g / L, 23 g / L, 24 g / L, 25 g / L, 26 g / L, 27 g / L, 28 g / L, 29 g / L, 30 g / L, 30.3 g / L; or a range of values ​​consisting of any two of the above points.

[0062] According to some embodiments of the present invention, the method further includes displacing the sponge indium from the indium-rich solution. The specific process of replacing indium sponge involves adjusting the pH of the indium-rich solution and then replacing it with an elemental metal.

[0063] The adjusted pH should be between 1.92 and 1.97. Specifically, it could be 1.92, 1.95, or 1.97; or a range consisting of any two of these values.

[0064] In actual production, filtration can be performed after adjusting the pH if necessary.

[0065] The metallic element is an aluminum or zinc sheet pretreated with 3-5% hydrochloric acid. Specifically, it could be 3%, 4%, or 5%; or a range consisting of any two of the above values.

[0066] The temperature for the displacement is 30~50℃. For example, it can be 30℃, 35℃, 40℃, 45℃, 50℃; or a range of values ​​consisting of any two of the above points.

[0067] The duration of the replacement is 2 to 4 hours; for example, it can be 2 hours, 3 hours, 4 hours; or a range of values ​​composed of any two of the above point values.

[0068] During the replacement process, the replacement rate of indium is 99.72% to 99.79%. For example, it can be 99.72%, 99.75%, 99.79%; or a range of values ​​consisting of any two of the above points.

[0069] The method further includes washing the resulting displacement product after the displacement and drying it. This removes any residual indium-rich solution.

[0070] The purity of the obtained sponge indium is ≥95%; specifically, it can be 95.2% to 96.4%. For example, it can be 95.2%, 95.5%, 96%, 96.4%; or a range of values ​​consisting of any two of the above points.

[0071] According to some embodiments of the present invention, in step S3, the concentration of ascorbic acid in the detergent is 0.3~0.5 mol / L. For example, it can specifically be 0.3 mol / L, 0.4 mol / L, 0.5 mol / L; or a range of values ​​consisting of any two of the above points.

[0072] According to some embodiments of the present invention, in step S3, the concentration of hydrochloric acid in the detergent is 2~4 mol / L. For example, it can be 2 mol / L, 2.5 mol / L, 3 mol / L, 3.5 mol / L, 4 mol / L; or a range of values ​​consisting of any two of the above points.

[0073] This ensures the iron back-extraction rate while minimizing corrosion of the equipment.

[0074] According to some embodiments of the present invention, in step S3, the O / A ratio of the wash is 4 to 6:1. For example, it can be 4:1, 5:1, 6:1; or a range of values ​​composed of any two of the above points.

[0075] According to some embodiments of the present invention, in step S3, the number of washing stages is 2 to 3.

[0076] According to some embodiments of the present invention, in step S3, the washing method is cross-flow washing.

[0077] According to some embodiments of the present invention, in step S3, after washing, (1 - iron in the iron-removed organic phase / iron in the supported organic phase) ≥ 95%. Specifically, this could be 95%, 95.2%, 96%, 97%, 98%, 99%, 99.4%, 99.5%; or a range of values ​​consisting of any two of the above points. This achieves deep removal of iron from the first organic phase.

[0078] According to some embodiments of the present invention, in step S3, the second stripping agent is an alkaline stripping agent.

[0079] According to some embodiments of the present invention, in step S3, the second stripping agent comprises an aqueous solution of sodium hydroxide at a concentration of 1.5 to 3.5 mol / L. Specifically, it can be 1.5 mol / L, 2 mol / L, 2.5 mol / L, 3 mol / L, or 3.5 mol / L; or a range consisting of any two of the above values.

[0080] The back-extraction process using the second back-extractant is also accompanied by the saponification of the iron-removing organic phase, which can change the charge form and polarity of the extractant P204, promote the extraction ability of the subsequently regenerated first organic phase for metal ions, facilitate the reuse of the first organic phase, and improve the extraction rate of indium and molybdenum during the reuse of the first organic phase.

[0081] According to some embodiments of the present invention, in step S3, the molybdenum is back-extracted with an O / A ratio of 4:1.

[0082] According to some embodiments of the present invention, in step S3, the back-extraction of molybdenum is performed by cross-flow back-extraction; specifically, the number of stages is 2 to 4. For example, it can specifically be 3 stages.

[0083] According to some embodiments of the present invention, in step S3, the molybdenum back-extraction rate reaches 97.5% to 98.7%. For example, it can specifically be 97.5%, 98%, 98.5%, 98.7%; or a range of values ​​composed of any two of the above points.

[0084] According to some embodiments of the present invention, the concentration of molybdenum in the molybdenum-rich solution is 4~8 g / L. For example, it can be 4 g / L, 4.5 g / L, 5 g / L, 5.5 g / L, 6 g / L, 6.5 g / L, 7 g / L, 7.5 g / L, 8 g / L; or a range of values ​​consisting of any two of the above points.

[0085] According to some embodiments of the present invention, the method further includes crystallizing molybdate from the molybdenum-rich solution. The crystallization process involves sequential evaporation crystallization and recrystallization. The evaporation temperature during evaporation crystallization is 90–100°C; the temperature for cooling crystallization is 0–5°C.

[0086] The purity of the obtained molybdate is ≥99%. For example, it can be 99.1% to 99.4%. For example, it can be 99.1%, 99.2%, 99.3%, 99.4%; or a range of values ​​consisting of any two of the above points.

[0087] The molybdenum back-extraction process also serves as a regeneration process for the first organic phase. The regenerated first organic phase can be reused at least 7 times. The standard for reuse is that the extraction rates of both indium and molybdenum are ≥95%, with the indium extraction rate reaching 98%. The recycling of the first organic phase, resin, and subsequently the second organic phase enables the recycling of process raw materials, reducing production costs.

[0088] According to some embodiments of the present invention, in step S4, the organic acid includes at least one of tartaric acid, oxalic acid, and citric acid. This allows it to complex with germanium in the raffinate. Tartaric acid has a stronger complexing ability with germanium ions than the other two organic acids.

[0089] According to some embodiments of the present invention, in the mixed system of organic acid and raffinate, the concentration of organic acid is 650~1000 mg / L. Specifically, it can be 650 mg / L, 700 mg / L, 750 mg / L, 800 mg / L, 850 mg / L, 900 mg / L, 950 mg / L, 1000 mg / L; or a range consisting of any two of the above values.

[0090] According to some embodiments of the present invention, step S4 further includes adjusting the pH of the germanium-containing solution to 8.5-10.0 after the mixing reaction. For example, it can specifically be 8.5, 9, 9.5, 10; or a range of values ​​consisting of any two of the above points.

[0091] According to some embodiments of the present invention, in step S4, the O / A ratio of the extraction is 1:1 to 4. For example, it can be 1:1, 1:2, 1:3, 1:4; or a range of values ​​composed of any two of the above points.

[0092] According to some embodiments of the present invention, in step S4, the extraction method includes cross-flow extraction. Specifically, the number of extraction stages is 2 to 4 stages.

[0093] According to some embodiments of the present invention, in step S4, the volume fraction of N235 in the second organic phase is 25-35%. For example, it can be 25%, 26%, 28%, 30%, 32%, 34%, 35%; or a range of values ​​composed of any two of the above points.

[0094] According to some embodiments of the present invention, in step S4, the concentration of TBP in the second organic phase is 10-20%. For example, it can be 10%, 12%, 14%, 15%, 16%, 18%, 20%; or a range of values ​​consisting of any two of the above points.

[0095] Within the above-mentioned N235 and TBP concentration range, germanium extraction can be effectively achieved, the formation of a third phase can be prevented, and the emulsification of the organic phase can also be prevented.

[0096] According to some embodiments of the present invention, in step S4, the second organic phase further includes a diluent. The diluent includes sulfonated kerosene. The amount of sulfonated kerosene used is the balance of N235 and TBP.

[0097] According to some embodiments of the present invention, in step S4, the extraction rate of germanium is 96.2% to 98.3%. For example, it can be 96.2%, 96.5%, 97%, 97.5%, 98%, 98.3%; or a range of values ​​consisting of any two of the above points.

[0098] According to some embodiments of the present invention, in step S4, the O / A ratio of the back-extraction is 2 to 4:1. For example, it can be 2:1, 3:1, 4:1; or a range of values ​​composed of any two of the above points.

[0099] According to some embodiments of the present invention, in step S4, the back-extraction method includes cross-flow back-extraction. Specifically, the number of back-extraction stages is 2 to 4.

[0100] According to some embodiments of the present invention, in step S4, the stripping agent used for stripping is an aqueous sodium hydroxide solution. The concentration of the aqueous sodium hydroxide solution is 2.5~3.5 mol / L. Specifically, it can be 3.5 mol / L, 3 mol / L, 3.2 mol / L, 3.5 mol / L; or a range consisting of any two of the above values. Using an aqueous sodium hydroxide solution can disrupt the complexation state between the organic acid and germanium ions, thereby achieving the stripping of germanium.

[0101] When the concentration of sodium hydroxide aqueous solution is ≥3.2mol / L, the germanium back-extraction rate is ≥94%. For example, it can be 94%, 94.5%, 95%, 95.5%, 96%, 96.5%, 97%, 97.5%, 98%, 98.5%, 99%; or a range of values ​​consisting of any two of the above points.

[0102] According to some embodiments of the present invention, in step S4, the germanium back-extraction rate is 94.5% to 97.5%. For example, it can be 94.5%, 95%, 95.5%, 96%, 96.5%, 97%, 97.5%; or a range of values ​​consisting of any two of the above points.

[0103] According to some embodiments of the present invention, in step S4, the blank organic phase after germanium back-extraction can be regenerated and reused. The germanium back-extraction process also serves as a second organic phase regeneration process. The number of reuses is ≥5 times. The standard for regeneration and reuse is that the extraction rate and back-extraction rate of the regenerated second organic phase for germanium are both ≥90%.

[0104] According to some embodiments of the present invention, in step S4, the concentration of germanium in the germanium-rich solution is 143.4~151.2 mg / L. For example, it can specifically be 143.4 mg / L, 145 mg / L, 148 mg / L, 150 mg / L, 151.2 mg / L; or a range of values ​​consisting of any two of the above points.

[0105] According to some embodiments of the present invention, the method further includes precipitating germanium salt from the germanium-rich solution.

[0106] According to some embodiments of the present invention, the precipitant used to precipitate germanium salt from the germanium-rich solution includes tannic acid. Thus, the obtained germanium salt includes germanium tannate. The germanium content in the tannin germanium is ≥1.3%. For example, it can be 1.48~1.76%. For example, it can be 1.48%, 1.5%, 1.55%, 1.6%, 1.65%, 1.7%, 1.75%, 1.76%; or a range of values ​​consisting of any two of the above points.

[0107] The germanium precipitation rate is 98.6% to 99.4%. For example, it can be 98.6%, 99%, 99.4%; or a range of values ​​consisting of any two of the above points.

[0108] According to some embodiments of the present invention, the method further includes adjusting the pH of the germanium-rich solution to 1.76-1.93 before precipitating the germanium salt, followed by filtration. Specifically, the pH could be 1.76, 1.8, 1.85, 1.9, 1.93; or a range consisting of any two of the above values.

[0109] According to some embodiments of the present invention, the temperature for precipitating the germanium salt is 40~50°C; for example, it can be 40°C, 45°C, 50°C; or a range of any two of the above values; the reaction time is 30~60 min.

[0110] According to some embodiments of the present invention, unless otherwise specified, the implementation temperature of the method is room temperature, specifically 5~20℃. For example, it can be 5℃, 10℃, 15℃, 20℃; or a range of values ​​composed of any two of the above points.

[0111] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0112] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a flowchart illustrating the method provided in Embodiment 1 of the present invention. Detailed Implementation

[0113] The following will describe the concept and technical effects of the present invention clearly and completely with reference to embodiments, so as to fully understand the purpose, features and effects of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention.

[0114] Example 1 This example provides a method for recovering rare and dispersed metals from industrial wastewater, specifically: The industrial wastewater used was the liquid obtained after reducing white smoke dust from copper smelting, and it was filtered using a 0.45-micron filter membrane before use. The main parameters of the resulting filtrate are as follows: Re: 30.5mg / L, Mo: 512.4mg / L, In: 568.7mg / L, Ge: 80.2mg / L, As: 10784mg / L, Fe: 16480mg / L, Zn: 143107mg / L, Cd: 2481 3mg / L; Bi: 215.7mg / L, Cu: 150.4mg / L; Pb: 9.9mg / L, Al: 610.5mg / L, F: 1179.1mg / L, Cl: 500.2mg / L, phenolphthalein acidity: 6.21mol / L.

[0115] S1. Industrial wastewater filtered by resin adsorption is used to obtain loaded resin and adsorbed liquid; the loaded resin is desorbed with ammonia water to obtain rhenium-rich solution; The adsorption method involved passing industrial wastewater through an exchange column packed with 100 mL of A1701 macroporous weakly basic anion exchange resin (fresh, produced by Purolite, a subsidiary of Ecolab); the influent flow rate was 4 Bv / h; and the rhenium adsorption rate was 96.5% and the adsorption capacity was 8.81 g / L when the influent flow rate was 320 Bv (with a rhenium concentration of 3 mg / L in the effluent as the breakthrough point). (The resin's adsorption rates for molybdenum, fluorine, and chlorine were <3%, and it did not adsorb other ions.) Desorption was performed using 3% ammonia water at a flow rate of 2 Bv / h, achieving a desorption rate of 93.3%. Finally, a rhenium-rich solution (rhenium concentration 2.76 g / L) was obtained. This solution was then concentrated by rotary evaporation at 88℃ under negative pressure until crystals precipitated, followed by freeze-crystallization at 0–5℃ and recrystallization (recrystallization solvent was deionized water, solid-liquid ratio was 1:5), yielding ammonium perrhenate with a purity of 99.992%.

[0116] In actual production, the desorbed resin can be regenerated with 5% sulfuric acid and reused.

[0117] S2. The adsorption solution (indium: 568.7 mg / L, molybdenum: 512.4 mg / L) was extracted with the first organic phase to obtain the loaded organic phase and the raffinate; the first organic phase included P2O4; The first organic phase consists of 35% by volume P2O4 and 65% by volume sulfonated kerosene.

[0118] The O / A ratio of the extract was 1:8, and the extraction method was two-stage cross-flow extraction (the extraction rates of indium and molybdenum were 98.8% and 98.5%, respectively).

[0119] S3. After washing the supported organic phase with water, the supported organic phase is back-extracted using the first back-extracting agent to obtain an indium-rich solution and the remaining organic phase; The remaining organic phase is washed with a detergent to remove iron, resulting in an iron-free organic phase; the detergent includes ascorbic acid and hydrochloric acid. After washing the iron-removed organic phase again with water, the iron-removed organic phase is back-extracted with a second back-extracting agent to obtain a molybdenum-rich solution. The O / A ratio of the first wash is 1:5, which is a first-stage wash; The first stripping agent is 4 mol / L hydrochloric acid. The O / A ratio of the first stripping is 10:1. The first stripping method is three-stage cross-flow stripping of indium (stripping rate 99.6%, initial iron removal rate of about 9.5%).

[0120] The detergent is a mixed aqueous solution of hydrochloric acid and ascorbic acid, wherein the concentration of hydrochloric acid is 2 mol / L and the concentration of ascorbic acid is 0.3 mol / L; the O / A ratio of the washing is 5:1; the washing method is three-stage cross-flow back-extraction of iron, with an iron removal rate of 95.2%, where the iron removal rate is (1 - iron in the iron-removed organic phase / iron in the supported organic phase). The O / A ratio of the second wash is 1:5, which is a first-stage wash; The second stripping agent is 2 mol / L NaOH; the O / A ratio for the second stripping is 4:1; the second stripping method is two-stage cross-flow stripping of molybdenum at room temperature (stripping rate 98.0%).

[0121] The indium-rich solution (containing 22.5 g / L indium) was collected, and the pH was adjusted to 1.92 using sodium hydroxide and filtered. The indium concentration remained unchanged before and after filtration. Subsequently, aluminum sheets pretreated with 5% hydrochloric acid (immersion treatment; the solid-liquid ratio did not affect the results) were added, and the mixture was reacted in a constant temperature water bath at 50°C for 3 hours. The aluminum sheets with indium sponge were rinsed with distilled water to remove residual indium chloride solution. The rinsed product was filtered to separate the indium sponge and the filtrate. The indium sponge was then placed in a drying oven and dried at 80°C for 8 hours to obtain the dried indium sponge product. Under these conditions, the indium concentration in the solution after displacement was 47.1 mg / L, the displacement rate was 99.79%, and the purity of the indium sponge reached 95.2%.

[0122] The molybdenum-rich solution (containing 7.5 g / L of molybdenum) was concentrated by rotary evaporation under negative pressure (water bath temperature of 90~100℃) and then frozen to crystallize (0~5℃) to obtain crude sodium molybdate. The crude sodium molybdate was then recrystallized again to obtain sodium molybdate with a purity of 99.1%.

[0123] The recrystallization method involves dissolving crude sodium molybdate in water at a solid-liquid mass ratio of 1:2.5, filtering to remove impurities, and then cooling to crystallize and obtain the precipitated crystals.

[0124] S4. Mix the organic acid and the raffinate to obtain a germanium-containing solution; A second organic phase was used to extract the germanium-containing feed solution to obtain a germanium-supported organic phase; the second organic phase included N235 and TBP. Germanium-supported organic phase is back-extracted to obtain a germanium-rich solution.

[0125] The organic acid is tartaric acid. In the system obtained by mixing the organic acid and the raffinate, the concentration of tartaric acid is 800 mg / L.

[0126] The second organic phase is a mixture of 30% by volume N235, 15% by volume TBP and 55% by volume kerosene.

[0127] In the extraction using the second organic phase, the O / A ratio was 1:2; the extraction was a two-stage cross-flow extraction (germanium extraction rate 96.2%). The stripping agent for the germanium-supported organic phase was 3.2 mol / L NaOH; the O / A ratio was 2:1; the extraction method was two-stage cross-flow stripping (germanium stripping rate 94.5%). The germanium-rich solution (containing 151.2 mg / L of germanium) was adjusted to pH 1.93 with 5% sulfuric acid, filtered, and then tannic acid was added at 40°C for 30 min. The amount of tannic acid added was 50 times that of germanium. After germanium precipitation, the germanium concentration in the solution was 2.1 mg / L, the germanium precipitation rate reached 98.6%, and the germanium grade reached 1.76% (the germanium grade in tannic acid germanium), meeting the standard of grade 5 germanium concentrate.

[0128] Unless otherwise specified, the implementation temperature in this example is 12℃ (room temperature).

[0129] Example 2 This example provides a method for recovering rare and dispersed metals from industrial wastewater, specifically: The industrial wastewater used was the liquid obtained after reducing white smoke dust from copper smelting, and it was filtered using a 0.45-micron filter membrane before use. The main parameters of the resulting filtrate are as follows: Re: 30.5mg / L, Mo: 512.4mg / L, In: 568.7mg / L, Ge: 80.2mg / L, As: 10784mg / L, Fe: 16480mg / L, Zn: 143107mg / L, Cd: 2481 3mg / L; Bi: 215.7mg / L, Cu: 150.4mg / L; Pb: 9.9mg / L, Al: 610.5mg / L, F: 1179.1mg / L, Cl: 500.2mg / L, phenolphthalein acidity: 6.21mol / L.

[0130] S1. Industrial wastewater filtered by resin adsorption is used to obtain loaded resin and adsorbed liquid; the loaded resin is desorbed with ammonia water to obtain rhenium-rich solution; The adsorption method involved passing industrial wastewater through an exchange column packed with 100 mL of A1701 macroporous weakly basic anion exchange resin (reusable once); the influent flow rate was 4 Bv / h; when the influent flow rate was 320 Bv (with a rhenium concentration of 3 mg / L in the effluent as the breakthrough point), the rhenium adsorption rate was 97.3% and the adsorption capacity was 10.7 g / L (the resin's adsorption rates for molybdenum, fluorine, and chlorine were <3%, and it did not adsorb other ions). Desorption was performed using 5% ammonia water at a flow rate of 2 Bv / h, achieving a desorption rate of 94.2%. Finally, a rhenium-rich solution (rhenium concentration 2.89 g / L) was obtained. This solution was then concentrated by rotary evaporation under negative pressure at 90℃, followed by freeze crystallization at 0-5℃ and recrystallization (solid-liquid ratio of 1:5) to obtain ammonium perrhenate with a purity of 99.991%.

[0131] S2. The adsorbate is extracted with a first organic phase (which can be reused once) to obtain a loaded organic phase and a raffinate; the first organic phase includes P2O4; The first organic phase consists of 35% by volume P2O4 and 65% by volume sulfonated kerosene.

[0132] The O / A ratio of the extract was 1:8, and the extraction method was two-stage cross-flow extraction (the extraction rates of indium and molybdenum were 99.4% and 98.7%, respectively).

[0133] S3. After washing the supported organic phase with water, the supported organic phase is back-extracted using the first back-extracting agent to obtain an indium-rich solution and the remaining organic phase; The remaining organic phase is washed with a detergent to remove iron, resulting in an iron-free organic phase; the detergent includes ascorbic acid and hydrochloric acid. After washing the iron-removed organic phase again with water, the iron-removed organic phase is back-extracted with a second back-extracting agent to obtain a molybdenum-rich solution. The O / A ratio of the first wash is 1:5, which is a first-stage wash; The first stripping agent is 4 mol / L hydrochloric acid. The O / A ratio of the first stripping is 10:1. The first stripping method is three-stage cross-flow stripping of indium (stripping rate 99.89%, initial iron removal rate of about 12.5%).

[0134] The detergent is a mixed aqueous solution of hydrochloric acid and ascorbic acid, with the concentration of hydrochloric acid being 3 mol / L and the concentration of ascorbic acid being 0.4 mol / L; the O / A ratio of the detergent is 5:1; the detergent method is three-stage cross-flow back-extraction of iron (iron removal rate 97.0%). The O / A ratio of the second wash is 1:5, which is a first-stage wash; The second stripping agent is 2 mol / L NaOH; the O / A ratio for the second stripping is 4:1; the second stripping method is two-stage cross-flow stripping of molybdenum at room temperature (stripping rate 97.5%).

[0135] The indium-rich solution (containing 30.3 g / L indium) was collected, and the pH was adjusted to 1.95 using sodium hydroxide followed by filtration. The indium concentration remained unchanged before and after filtration. Subsequently, aluminum sheets pretreated with 5% hydrochloric acid were added, and the mixture was reacted in a constant-temperature water bath at 50°C for 3 hours. The aluminum sheets coated with sponge indium were rinsed with distilled water to remove residual indium chloride solution. The rinsed product was then filtered to separate the sponge indium and the filtrate. The sponge indium was placed in a drying oven and dried at 80°C for 8 hours to obtain the dried sponge indium product. Under these conditions, the indium concentration in the solution after displacement was 84.5 mg / L, the displacement rate was 99.75%, and the purity of the sponge indium reached 96.4%.

[0136] The molybdenum-rich solution (containing 6.5 g / L of molybdenum) was concentrated by rotary evaporation under negative pressure (water bath temperature of 90~100℃) and then frozen to crystallize (0~5℃) to obtain crude sodium molybdate. The crude sodium molybdate was then recrystallized again to obtain sodium molybdate with a purity of 99.4%.

[0137] S4. Mix the organic acid and the raffinate to obtain a germanium-containing solution; A second organic phase was used to extract the germanium-containing feed solution to obtain a germanium-supported organic phase; the second organic phase included N235 and TBP. Germanium-supported organic phase is back-extracted to obtain a germanium-rich solution.

[0138] The organic acid is tartaric acid. In the system obtained by mixing the organic acid and the raffinate, the concentration of tartaric acid is 800 mg / L.

[0139] The second organic phase is a mixture of 30% by volume N235, 15% by volume TBP and 55% by volume kerosene (for the first reuse).

[0140] In the extraction using the second organic phase, the O / A ratio was 1:2; the extraction was a two-stage cross-flow extraction (germanium extraction rate 98.3%). The stripping agent for the germanium-supported organic phase was 3.2 mol / L NaOH; the O / A ratio was 2:1; the extraction method was two-stage cross-flow stripping (germanium stripping rate 95.5%). The germanium-rich solution (containing 145.0 mg / L of germanium) was adjusted to pH 1.76 with 5% sulfuric acid. After filtration, tannic acid (50 molar amounts of germanium) was added at 40°C and reacted for 30 minutes. After germanium precipitation, the germanium concentration in the solution was 0.87 mg / L, the germanium precipitation rate reached 99.0%, and the germanium grade reached 1.65%, meeting the standard for grade 5 germanium concentrate.

[0141] Unless otherwise specified, the implementation temperature in this example is 10℃ (room temperature).

[0142] Example 3 This example provides a method for recovering rare and dispersed metals from industrial wastewater, specifically: The industrial wastewater used was the liquid obtained after reducing white smoke dust from copper smelting, and it was filtered using a 0.45-micron filter membrane before use. The main parameters of the resulting filtrate are as follows: Re: 30.5mg / L, Mo: 512.4mg / L, In: 568.7mg / L, Ge: 80.2mg / L, As: 10784mg / L, Fe: 16480mg / L, Zn: 143107mg / L, Cd: 2481 3mg / L; Bi: 215.7mg / L, Cu: 150.4mg / L; Pb: 9.9mg / L, Al: 610.5mg / L, F: 1179.1mg / L, Cl: 500.2mg / L, phenolphthalein acidity: 6.21mol / L.

[0143] S1. Industrial wastewater filtered by resin adsorption is used to obtain loaded resin and adsorbed liquid; the loaded resin is desorbed with ammonia water to obtain rhenium-rich solution; The adsorption method involved passing industrial wastewater through an exchange column containing 100 mL of A1701 macroporous weakly basic anion exchange resin (used twice). The influent flow rate was 4 Bv / h. When the influent flow rate was 320 Bv (with a rhenium concentration of 3 mg / L in the effluent as the breakthrough point), the rhenium adsorption rate was 96.1% and the adsorption capacity was 11.0 g / L (the resin's adsorption rate for molybdenum, fluorine, and chlorine was <3%, and it did not adsorb other ions). Desorption was performed using 7% ammonia water at a flow rate of 2 Bv / h, achieving a desorption rate of 96.8%. Finally, a rhenium-rich solution (rhenium concentration 3.48 g / L) was obtained. This solution was then concentrated by rotary evaporation under negative pressure at 90℃, followed by freeze crystallization at 0-5℃ and recrystallization (solid-liquid ratio 1:5) to obtain ammonium perrhenate with a purity of 99.990%.

[0144] S2. The adsorption solution is extracted with the first organic phase (reused for the second time) to obtain the loaded organic phase and the raffinate; the first organic phase includes P2O4; The first organic phase consists of 35% by volume P2O4 and 65% by volume sulfonated kerosene.

[0145] The O / A ratio of the extract was 1:8, and the extraction method was two-stage cross-flow extraction (the extraction rates of indium and molybdenum were 99.0% and 98.5%, respectively).

[0146] S3. After washing the supported organic phase with water, the supported organic phase is back-extracted using the first back-extracting agent to obtain an indium-rich solution and the remaining organic phase; The remaining organic phase is washed with a detergent to remove iron, resulting in an iron-free organic phase; the detergent includes ascorbic acid and hydrochloric acid. After washing the iron-removed organic phase again with water, the iron-removed organic phase is back-extracted with a second back-extracting agent to obtain a molybdenum-rich solution. The O / A ratio of the first wash is 1:5, which is a first-stage wash; The first stripping agent is 4 mol / L hydrochloric acid. The O / A ratio of the first stripping is 10:1. The first stripping method is three-stage cross-flow stripping of indium (stripping rate 99.8%, initial iron removal rate of about 11.8%).

[0147] The detergent is a mixed aqueous solution of hydrochloric acid and ascorbic acid, with the concentration of hydrochloric acid being 4 mol / L and the concentration of ascorbic acid being 0.5 mol / L; the O / A ratio of the detergent is 5:1; the detergent method is three-stage cross-flow back-extraction of iron (iron removal rate 99.4%). The O / A ratio of the second wash is 1:5, which is a first-stage wash; The second stripping agent is 2 mol / L NaOH; the O / A ratio for the second stripping is 4:1; the second stripping method is two-stage cross-flow stripping of molybdenum at room temperature (stripping rate 98.7%).

[0148] The indium-rich solution (containing 28.0 g / L indium) was collected, and the pH was adjusted to 1.97 using sodium hydroxide and filtered. The indium concentration remained unchanged before and after filtration. Subsequently, aluminum sheets pretreated with 5% hydrochloric acid were added, and the mixture was reacted in a constant-temperature water bath at 50°C for 3 hours. The aluminum sheets coated with sponge indium were rinsed with distilled water to remove residual indium chloride solution. The rinsed product was filtered to separate the sponge indium and the filtrate. The sponge indium was placed in a drying oven and dried at 80°C for 8 hours to obtain the dried sponge indium product. Under these conditions, the indium concentration in the solution after displacement was 72.6 mg / L, the displacement rate was 99.72%, and the purity of the sponge indium reached 95.5%.

[0149] The molybdenum-rich solution (containing 4.84 g / L of molybdenum) was concentrated by rotary evaporation under negative pressure (water bath temperature of 90~100℃) and then frozen to crystallize (0~5℃) to obtain crude sodium molybdate. The crude sodium molybdate was then recrystallized again to obtain sodium molybdate with a purity of 99.2%.

[0150] S4. Mix the organic acid and the raffinate to obtain a germanium-containing solution; A second organic phase was used to extract the germanium-containing feed solution to obtain a germanium-supported organic phase; the second organic phase included N235 and TBP. Germanium-supported organic phase is back-extracted to obtain a germanium-rich solution.

[0151] The organic acid is tartaric acid. In the system obtained by mixing the organic acid and the raffinate, the concentration of tartaric acid is 800 mg / L.

[0152] The second organic phase is a mixture of 30% by volume N235, 15% by volume TBP and 55% by volume kerosene (for second reuse).

[0153] In the extraction using the second organic phase, the O / A ratio was 1:2; the extraction was a two-stage cross-flow extraction (germanium extraction rate 97.0%). The stripping agent for the germanium-supported organic phase was 3.2 mol / L NaOH; the O / A ratio was 2:1; the extraction method was two-stage cross-flow stripping (germanium stripping rate 96.0%, germanium content: 145.2 mg / L). The pH was adjusted to 1.82 with 5% sulfuric acid, filtered, and tannic acid (50 molar amounts of germanium) was added at 40℃ and reacted for 30 min. After germanium precipitation, the germanium concentration in the liquid was 1.24 mg / L, the germanium precipitation rate reached 99.4%, and the germanium grade reached 1.76%, meeting the standard of grade 5 germanium concentrate.

[0154] Unless otherwise specified, the implementation temperature in this example is 10℃ (room temperature).

[0155] Comparative Example 1 This example provides a method for recovering rare and dispersed metals from industrial wastewater, specifically: The industrial wastewater used was the liquid obtained after reducing white smoke dust from copper smelting, and it was filtered using a 0.45-micron filter membrane before use. The main parameters of the resulting filtrate are as follows: Re: 30.5mg / L, Mo: 512.4mg / L, In: 568.7mg / L, Ge: 80.2mg / L, As: 10784mg / L, Fe: 16480mg / L, Zn: 143107mg / L, Cd: 2481 3mg / L; Bi: 215.7mg / L, Cu: 150.4mg / L; Pb: 9.9mg / L, Al: 610.5mg / L, F: 1179.1mg / L, Cl: 500.2mg / L, phenolphthalein acidity: 6.21mol / L.

[0156] S1. Industrial wastewater filtered by resin adsorption is used to obtain loaded resin and adsorbed liquid; the loaded resin is desorbed with ammonia water to obtain rhenium-rich solution; The adsorption method involved passing industrial wastewater through an exchange column packed with 100 mL of A1701 macroporous weakly basic anion exchange resin (new resin); the influent flow rate was 8 Bv / h; when the influent flow rate was 284 Bv (with a rhenium concentration of 3 mg / L in the effluent as the breakthrough point), the rhenium adsorption rate was 97.3% and the adsorption capacity was 11.27 g / L (the resin's adsorption rate for molybdenum, fluorine, and chlorine was <3%, and it did not adsorb other ions). Desorption was performed using 5% ammonia water at a flow rate of 4 Bv / h, achieving a desorption rate of 87.2%. Finally, a rhenium-rich solution (rhenium concentration 2.23 g / L) was obtained. This solution was then concentrated by rotary evaporation under negative pressure at 90 °C, followed by freeze crystallization at 0–5 °C and recrystallization (solid-liquid ratio of 1:5) to obtain ammonium perrhenate with a purity of 99.992%.

[0157] S2. The adsorption solution was extracted with the first organic phase (fresh first organic phase) to obtain the loaded organic phase and the raffinate; The first organic phase consists of 35% by volume P2O4 and 65% by volume sulfonated kerosene.

[0158] The O / A ratio of the extract was 1:8, and the extraction method was two-stage cross-flow extraction (the extraction rates of indium and molybdenum were 98.8% and 98.7%, respectively).

[0159] S3. After washing the supported organic phase with water, the supported organic phase is back-extracted using the first back-extracting agent to obtain an indium-rich solution and the remaining organic phase; The remaining organic phase is washed with a detergent to remove iron, resulting in an iron-free organic phase; the detergent includes ascorbic acid and hydrochloric acid. After washing the iron-removed organic phase again with water, the iron-removed organic phase is back-extracted with a second back-extracting agent to obtain a molybdenum-rich solution. The O / A ratio of the first wash is 1:5, which is a first-stage wash; The first stripping agent is 4 mol / L hydrochloric acid. The O / A ratio of the first stripping is 10:1. The first stripping method is three-stage cross-flow stripping of indium (stripping rate 99.6%, initial iron removal rate of about 9.5%).

[0160] The detergent is a mixed aqueous solution of hydrochloric acid and ascorbic acid, with the concentration of hydrochloric acid being 3 mol / L and the concentration of ascorbic acid being 0.4 mol / L; the O / A ratio of the detergent is 5:1; the detergent method is three-stage cross-flow back-extraction of iron (iron removal rate 96.0%). The O / A ratio of the second wash is 1:5, which is a first-stage wash; The second stripping agent is 2 mol / L NaOH; the O / A ratio for the second stripping is 4:1; the second stripping method is two-stage cross-flow stripping of molybdenum at room temperature (stripping rate 98.5%). The blank organic phase obtained after the second stripping (also known as the regenerated organic phase) can be reused.

[0161] The indium-rich solution (containing 27.0 g / L indium) was collected, and the pH was adjusted to 1.95 using sodium hydroxide and filtered. The indium concentration remained unchanged before and after filtration. Subsequently, aluminum sheets pretreated with 5% hydrochloric acid were added, and the mixture was reacted in a constant-temperature water bath at 50°C for 3 hours. The aluminum sheets coated with indium sponge were rinsed with distilled water to remove residual indium chloride solution. The rinsed product was filtered to separate the indium sponge and the filtrate. The indium sponge was then placed in a drying oven and dried at 80°C for 8 hours to obtain the dried indium sponge product. Under these conditions, the indium concentration in the solution after displacement was 76.1 mg / L, the displacement rate was 99.75%, and the purity of the indium sponge reached 95.2%.

[0162] The molybdenum-rich solution (containing 7.0 g / L of molybdenum) was concentrated by rotary evaporation under negative pressure (water bath temperature of 90~100℃) and then frozen to crystallize (0~5℃) to obtain crude sodium molybdate. The crude sodium molybdate was then recrystallized again to obtain sodium molybdate with a purity of 99.1%.

[0163] S4. Mix the organic acid and the raffinate to obtain a germanium-containing solution; The germanium-containing feed solution was extracted using a second organic phase (fresh second organic phase) to obtain a germanium-supported organic phase; the second organic phase consisted of N235 and TBP; Germanium-supported organic phase is back-extracted to obtain a germanium-rich solution.

[0164] The organic acid is tartaric acid. In the system obtained by mixing the organic acid and the raffinate, the concentration of tartaric acid is 800 mg / L.

[0165] The second organic phase is a mixture of 30% by volume N235, 15% by volume TBP and 55% by volume kerosene.

[0166] In the extraction using the second organic phase, the O / A ratio was 1:2; the extraction was a two-stage cross-flow extraction (germanium extraction rate 97.5%). The stripping agent for the germanium-supported organic phase is 3.2 mol / L NaOH; the O / A ratio is 2:1; the extraction method is two-stage cross-flow stripping (germanium stripping rate 96.5%); the resulting blank organic phase (also known as the regenerated organic phase) can be reused.

[0167] The germanium-rich solution (containing 153.4 mg / L of germanium) was adjusted to pH 1.76 with 5% sulfuric acid. After filtration, tannic acid (50 molar amounts of germanium) was added at 40°C and reacted for 30 minutes. After germanium precipitation, the germanium concentration in the solution was 0.65 mg / L, the germanium precipitation rate reached 98.6%, and the germanium grade reached 1.48%, meeting the standard for grade 5 germanium concentrate.

[0168] Unless otherwise specified, the implementation temperature in this example is 10℃ (room temperature).

[0169] Comparative Example 2 This example provides a method for recovering rare and dispersed metals from industrial wastewater, specifically: The industrial wastewater used was the liquid obtained after reducing white smoke dust from copper smelting, and it was filtered using a 0.45-micron filter membrane before use. The main parameters of the resulting filtrate are as follows: Re: 30.5mg / L, Mo: 512.4mg / L, In: 568.7mg / L, Ge: 80.2mg / L, As: 10784mg / L, Fe: 16480mg / L, Zn: 143107mg / L, Cd: 2481 3mg / L; Bi: 215.7mg / L, Cu: 150.4mg / L; Pb: 9.9mg / L, Al: 610.5mg / L, F: 1179.1mg / L, Cl: 500.2mg / L, phenolphthalein acidity: 6.21mol / L.

[0170] S1. Industrial wastewater filtered by resin adsorption is used to obtain loaded resin and adsorbed liquid; the loaded resin is desorbed with ammonia water to obtain rhenium-rich solution; The adsorption method involved passing industrial wastewater through an exchange column containing 100 mL of A1701 macroporous weakly basic anion exchange resin (reusable once); the influent flow rate was 4 Bv / h; when the influent flow rate was 320 Bv (with a rhenium concentration of 3 mg / L in the effluent as the breakthrough point), the rhenium adsorption rate was 96.5% and the adsorption capacity was 11.0 g / L (the resin's adsorption rate for molybdenum, fluorine, and chlorine was <3%, and it did not adsorb other ions). Desorption was performed using 5% ammonia water at a flow rate of 2 Bv / h, achieving a desorption rate of 93.1%. Finally, a rhenium-rich solution (rhenium concentration 2.74 g / L) was obtained. This solution was then concentrated by rotary evaporation under negative pressure at 90℃, followed by freeze-crystallization at 0-5℃ and recrystallization (solid-liquid ratio of 1:5) to obtain ammonium perrhenate with a purity of 99.994%.

[0171] S2. The first organic phase (first reuse) is used to extract the adsorption liquid to obtain the loaded organic phase and the raffinate; the first organic phase includes P2O4; The first organic phase consists of 35% by volume P2O4 and 65% by volume sulfonated kerosene.

[0172] The O / A ratio of the extract was 1:8, and the extraction method was two-stage cross-flow extraction (the extraction rates of indium and molybdenum were 99.2% and 97.5%, respectively).

[0173] S3. After washing the supported organic phase with water, the supported organic phase is back-extracted using the first back-extracting agent to obtain an indium-rich solution and the remaining organic phase; The remaining organic phase is washed with a detergent to remove iron, resulting in an iron-free organic phase; the detergent includes ascorbic acid and hydrochloric acid. After washing the iron-removed organic phase again with water, the iron-removed organic phase is back-extracted with a second back-extracting agent to obtain a molybdenum-rich solution. The O / A ratio of the first wash is 1:5, which is a first-stage wash; The first stripping agent is 4 mol / L hydrochloric acid. The O / A ratio of the first stripping is 10:1. The first stripping method is three-stage cross-flow stripping of indium (stripping rate 99.6%, initial iron removal rate of about 10.5%).

[0174] The detergent was 6 mol / L hydrochloric acid; the O / A ratio of the washing was 5:1; the washing method was three-stage cross-flow back-extraction of iron (iron removal rate 98.0%). The O / A ratio of the second wash is 1:5, which is a first-stage wash; The second stripping agent is 2 mol / L NaOH; the O / A ratio of the second stripping is 4:1; the second stripping method is two-stage cross-flow stripping of molybdenum at room temperature (stripping rate 92.4%).

[0175] The indium-rich solution (containing 29.0 g / L indium) was collected, and the pH was adjusted to 1.95 using sodium hydroxide and filtered. The indium concentration remained unchanged before and after filtration. Subsequently, aluminum sheets pretreated with 5% hydrochloric acid were added, and the mixture was reacted in a constant-temperature water bath at 50°C for 3 hours. The aluminum sheets coated with indium sponge were rinsed with distilled water to remove residual indium chloride solution. The rinsed product was filtered to separate the indium sponge and the filtrate. The indium sponge was then placed in a drying oven and dried at 80°C for 8 hours to obtain the dried indium sponge product. Under these conditions, the indium concentration in the solution after displacement was 54.1 mg / L, the displacement rate was 99.72%, and the purity of the indium sponge reached 96.0%.

[0176] The molybdenum-rich solution (containing 7.5 g / L of molybdenum) was concentrated by rotary evaporation under negative pressure (water bath temperature of 90~100℃) and then frozen to crystallize (0~5℃) to obtain crude sodium molybdate. The crude sodium molybdate was then recrystallized again to obtain sodium molybdate with a purity of 99.2%.

[0177] S4. Mix the organic acid and the raffinate to obtain a germanium-containing solution; The germanium-containing feed solution was extracted using a second organic phase to obtain a germanium-supported organic phase; Germanium-supported organic phase is back-extracted to obtain a germanium-rich solution.

[0178] The organic acid is tartaric acid. In the system obtained by mixing the organic acid and the raffinate, the concentration of tartaric acid is 800 mg / L.

[0179] The second organic phase is a mixture of 30% by volume N235, 15% by volume TBP and 55% by volume kerosene (first reuse).

[0180] In the extraction using the second organic phase, the O / A ratio was 1:2; the extraction was a two-stage cross-flow extraction (germanium extraction rate 98.0%). The stripping agent for the germanium-supported organic phase was 3.2 mol / L NaOH; the O / A ratio was 2:1; the extraction method was two-stage cross-flow stripping (germanium stripping rate 96.0%). The germanium-rich solution (containing 152.6 mg / L of germanium) was adjusted to pH 1.76 with 5% sulfuric acid. After filtration, tannic acid (50 molar amounts of germanium) was added at 40°C and reacted for 30 minutes. After germanium precipitation, the germanium concentration in the solution was 0.47 mg / L, the germanium precipitation rate reached 99.4%, and the germanium grade reached 1.75%, meeting the standard for grade 5 germanium concentrate.

[0181] Unless otherwise specified, the implementation temperature in this example is 10℃ (room temperature).

[0182] Comparative Example 3 This example provides a method for recovering rare and dispersed metals from industrial wastewater, specifically: The industrial wastewater used was the liquid obtained after reducing white smoke dust from copper smelting, and it was filtered using a 0.45-micron filter membrane before use. The main parameters of the resulting filtrate are as follows: Re: 30.5mg / L, Mo: 512.4mg / L, In: 568.7mg / L, Ge: 80.2mg / L, As: 10784mg / L, Fe: 16480mg / L, Zn: 143107mg / L, Cd: 2481 3mg / L; Bi: 215.7mg / L, Cu: 150.4mg / L; Pb: 9.9mg / L, Al: 610.5mg / L, F: 1179.1mg / L, Cl: 500.2mg / L, phenolphthalein acidity: 6.21mol / L.

[0183] S1. Industrial wastewater filtered by resin adsorption is used to obtain loaded resin and adsorbed liquid; the loaded resin is desorbed with ammonia water to obtain rhenium-rich solution; The adsorption method involved passing industrial wastewater through an exchange column containing 100 mL of A1701 macroporous weakly basic anion exchange resin (used twice). The influent flow rate was 4 Bv / h. When the influent flow rate was 320 Bv (with a rhenium concentration of 3 mg / L in the effluent as the breakthrough point), the rhenium adsorption rate was 96.5% and the adsorption capacity was 10.5 g / L (the resin's adsorption rate for molybdenum, fluorine, and chlorine was <3%, and it did not adsorb other ions). Desorption was performed using 5% ammonia water at a flow rate of 2 Bv / h, achieving a desorption rate of 96.3%. Finally, a rhenium-rich solution (rhenium concentration 3.11 g / L) was obtained. This solution was then concentrated by rotary evaporation at 90°C under negative pressure, followed by freeze-crystallization at 0-5°C and recrystallization (solid-liquid ratio of 1:5) to obtain ammonium perrhenate with a purity of 99.994%.

[0184] S2. The adsorption solution is extracted with the first organic phase to obtain the loaded organic phase and the raffinate; The first organic phase consists of 35% by volume P2O4 and 65% by volume sulfonated kerosene (used for a second time).

[0185] The O / A ratio of the extract was 1:8, and the extraction method was two-stage cross-flow extraction (the extraction rates of indium and molybdenum were 99.4% and 98.0%, respectively).

[0186] S3. After washing the supported organic phase with water, the supported organic phase is back-extracted using the first back-extracting agent to obtain an indium-rich solution and the remaining organic phase; The remaining organic phase is washed with a detergent to remove iron, resulting in an iron-free organic phase; the detergent includes ascorbic acid and hydrochloric acid. After washing the iron-removed organic phase again with water, the iron-removed organic phase is back-extracted with a second back-extracting agent to obtain a molybdenum-rich solution. The O / A ratio of the first wash is 1:5, which is a first-stage wash; The first stripping agent is 4 mol / L hydrochloric acid. The O / A ratio of the first stripping is 10:1. The first stripping method is three-stage cross-flow stripping of indium (stripping rate 99.6%, initial iron removal rate of about 11.5%).

[0187] The detergent is a mixed aqueous solution of hydrochloric acid and ascorbic acid, with the concentration of hydrochloric acid being 3 mol / L and the concentration of ascorbic acid being 0.4 mol / L; the O / A ratio of the detergent is 5:1; the detergent method is three-stage cross-flow back-extraction of iron (iron removal rate 95.0%). The O / A ratio of the second wash is 1:5, which is a first-stage wash; The second stripping agent is 2 mol / L NaOH; the O / A ratio for the second stripping is 4:1; the second stripping method is two-stage cross-flow stripping of molybdenum at room temperature (stripping rate 98.7%).

[0188] The indium-rich solution (containing 30.0 g / L indium) was collected, and the pH was adjusted to 1.98 using sodium hydroxide and filtered. The indium concentration remained unchanged before and after filtration. Subsequently, aluminum sheets pretreated with 5% hydrochloric acid were added, and the mixture was reacted in a constant-temperature water bath at 50°C for 3 hours. The aluminum sheets coated with sponge indium were rinsed with distilled water to remove residual indium chloride solution. The rinsed product was filtered to separate the sponge indium and the filtrate. The sponge indium was placed in a drying oven and dried at 80°C for 8 hours to obtain the dried sponge indium product. Under these conditions, the indium concentration in the solution after displacement was 42.3 mg / L, the displacement rate was 99.75%, and the purity of the sponge indium reached 95.2%.

[0189] The molybdenum-rich solution (containing 8.0 g / L of molybdenum) was concentrated by rotary evaporation under negative pressure (water bath temperature of 90~100℃) and then frozen to crystallize (0~5℃) to obtain crude sodium molybdate. The crude sodium molybdate was then recrystallized again to obtain sodium molybdate with a purity of 98.2%.

[0190] S4. Mix the organic acid and the raffinate to obtain a germanium-containing solution; The germanium-containing feed solution was extracted using a second organic phase to obtain a germanium-supported organic phase; Germanium-supported organic phase is back-extracted to obtain a germanium-rich solution.

[0191] The organic acid is tartaric acid. In the system obtained by mixing the organic acid and the raffinate, the concentration of tartaric acid is 600 mg / L.

[0192] The second organic phase is a mixture of 30% by volume N235, 15% by volume TBP and 55% by volume kerosene (for second reuse).

[0193] In the extraction using the second organic phase, the O / A ratio was 1:2; the extraction was a two-stage cross-flow extraction (germanium extraction rate 73.6%). The stripping agent for the germanium-supported organic phase was 3.2 mol / L NaOH; the O / A ratio was 2:1; the extraction method was two-stage cross-flow stripping (germanium stripping rate 94.5%). The germanium-rich solution (containing 118.6 mg / L of germanium) was adjusted to pH 1.76 with 5% sulfuric acid, filtered, and then tannic acid (50 molar amounts of germanium) was added at 40°C and reacted for 30 minutes. After germanium precipitation, the germanium concentration in the solution was 0.77 mg / L, the germanium precipitation rate was 93.53%, and the germanium grade was 0.87%, which did not meet the standard for grade 5 germanium concentrate.

[0194] Unless otherwise specified, the implementation temperature in this example is 10℃ (room temperature).

[0195] As can be seen from the above embodiments and comparative examples, within the range given by this invention, even with parameter adjustments, the individual separation of Re, In, Mo, and Ge can still be achieved, and the purity of the obtained product is high. However, in step S1, if the adsorption and desorption flow rates are not within the range required by this invention, the adsorption rate and desorption rate of rhenium will decrease. If the iron removal detergent is not within the range required by this invention, the iron back-extraction rate will decrease significantly, thus affecting the subsequent molybdenum back-extraction. If, in step S4, the concentration of organic acid is not within the range required by this invention, it will significantly affect the extraction and back-extraction of germanium, and even the grade of the final germanium-containing product. Based on the above advantages, the method provided by this invention can be used for the recycling of the liquid after the reduction of copper smelting white dust, and achieves excellent technical results.

[0196] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Furthermore, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

Claims

1. A method of recovering dispersed metals from industrial wastewater, characterized by, The industrial wastewater contains ionic rare and dispersed metals and impurities; the rare and dispersed metals include Re, Mo, In, and Ge; the impurities include Fe. The method includes the following steps: S1. The industrial wastewater is adsorbed with resin to obtain a loaded resin and an adsorbed liquid; the loaded resin is desorbed with ammonia to obtain a rhenium-rich solution; the resin is a macroporous weakly basic anion exchange resin; the adsorption flow rate is 4~6 BV / h; the desorption flow rate is 1~3 BV / h. S2. Extract the adsorbed liquid with a first organic phase to obtain a loaded organic phase and a raffinate; the first organic phase includes P2O4; S3. The supported organic phase is back-extracted using the first back-extracting agent to obtain an indium-rich solution and the remaining organic phase; The remaining organic phase is washed with a detergent to remove iron, resulting in an iron-free organic phase; the detergent includes ascorbic acid and hydrochloric acid; The iron-removed organic phase is back-extracted using a second back-extracting agent to obtain a molybdenum-rich solution; S4. The organic acid and the raffinate are mixed and reacted to obtain a germanium-containing solution; in the mixed system of the organic acid and the raffinate, the concentration of the organic acid is 650~1000 mg / L; The germanium-containing feed solution was extracted using a second organic phase to obtain a germanium-supported organic phase; the second organic phase comprised N235 and TBP. The germanium-supported organic phase was back-extracted to obtain a germanium-rich solution.

2. The method of claim 1, wherein, The impurities also include at least one of As, Zn, Cd, Bi, Cu, Pb, Al, F and Cl; And / or, the concentration of the rare and dispersed metals and impurities in the industrial wastewater is: Re30~37mg / L; Mo 315~513 mg / L; In568~775mg / L; Ge 64~81mg / L; Fe 12789~16480mg / L.

3. The method according to claim 1, characterized in that, In step S1, the mass concentration of the ammonia water is 3-7%.

4. The method according to claim 1, characterized in that, In step S3, the concentration of ascorbic acid in the detergent is 0.3~0.5 mol / L; and / or, in step S3, the concentration of hydrochloric acid in the detergent is 2~4 mol / L.

5. The method according to claim 1, characterized in that, In step S4, the volume fraction of N235 in the second organic phase is 25-35%; and / or, in step S4, the concentration of TBP in the second organic phase is 10-20%.

6. The method according to claim 1, characterized in that, In step S3, the first stripping agent is 3.5~4.5 mol / L hydrochloric acid; and / or, in step S3, the second stripping agent comprises 1.5~3.5 mol / L sodium hydroxide aqueous solution.

7. The method according to claim 1, characterized in that, In step S2, the O / A ratio of the extraction is 1:6 to 10; and / or, in step S4, the O / A ratio of the extraction is 1:1 to 4.

8. The method according to claim 1, characterized in that, The industrial wastewater includes the liquid resulting from the reduction of white smoke dust from copper smelting.

9. The method according to any one of claims 1 to 8, characterized in that, The method further includes crystallizing ammonium perrhenate from the rhenium-rich solution; And / or, the method further includes displacing sponge indium from the indium-rich solution; And / or, the method further includes crystallizing molybdate from the molybdenum-rich solution; And / or, the method further includes precipitating germanium salts from the germanium-rich solution.

10. The method according to claim 9, characterized in that, The precipitant used to precipitate germanium salts from the germanium-rich solution includes tannic acid; and / or, the method further includes adjusting the pH of the germanium-rich solution to 1.76 to 1.93 before precipitating the germanium salts.

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