A method for efficiently enriching gallium and separating iron from a pressurized zinc hydrometallurgy solution

Abstract

The present application relates to a method for efficiently enriching gallium and separating iron from pressurized zinc hydrometallurgy solution, comprising the following steps: oxidizing zinc oxygen pressure leaching solution to make Fe 2+ Oxidized into Fe 3+ , obtaining a first solution; adding PbO and ZnO to the first solution, adjusting pH to 2.0-2.4, obtaining a second solution; adding activated carbon to the second solution, adsorbing and filtering to obtain a gallium-rich precipitate; adding H2SO4 to the gallium-rich precipitate to leach zinc, obtaining a gallium enrichment; adding strong alkali to part of the gallium enrichment to leach, obtaining gallium alkali leaching solution and iron residue; if the gallium content in the gallium alkali leaching solution is 20-50 g / L, it can be collected, if the gallium content in the gallium alkali leaching solution is less than 20 g / L, it is mixed with another part of the gallium enrichment, strong alkali is added again, and the leaching is recycled; wherein the zinc oxygen pressure leaching solution comprises the following components: Zn 150-200 g / L, Fe 2+ 10-15 g / L, Fe 3+ 0.1-0.5 g / L, H2SO4 10-25 g / L, Ga 3+ 10-30 mg / L. The present application improves the enrichment degree of gallium and realizes the effective separation of gallium.

Description

Technical Field

[0001] This invention relates to the field of gallium recovery and extraction technology, specifically to a method for efficiently enriching gallium and separating iron from pressurized wet zinc smelting solutions. Background Technology

[0002] Gallium is a crucial basic material supporting the development of modern high-tech fields such as computers, 5G communications, aerospace, new energy, and medicine.

[0003] Gallium is extremely dispersed in the Earth's crust, mainly occurring in non-ferrous metal deposits such as zinc and aluminum. Currently, 90% of the world's gallium comes from aluminum smelting, and 10% from zinc smelting.

[0004] Traditional wet zinc smelting uses a roasting-leaching process. During roasting, gallium is contained in zinc ferrite. In the subsequent atmospheric pressure leaching process, gallium is contained in the leaching residue. When the leaching residue is volatilized in a rotary kiln, gallium remains in the kiln slag and is difficult to recover.

[0005] When zinc concentrate is directly processed using a pressurized wet leaching process, over 90% of gallium is leached into the solution. Subsequent zinc powder replacement processing of the zinc-oxygen pressure leaching solution enriches gallium in the replacement slag, but the gallium enrichment efficiency is low, only 50%. Meanwhile, the gallium phase in the replacement slag is complex, leading to problems such as a lengthy process and low recovery rate in subsequent gallium recovery from the slag.

[0006] Due to Ga 3+ with Fe 3+ With similar radii, Ga is used in pressurized wet zinc smelting processes. 3+ with Fe 3+ The trends are relatively consistent: the core problem in gallium enrichment is how to efficiently precipitate gallium from pressurized wet zinc smelting solutions and how to quickly separate gallium from iron in gallium-enriched products. Summary of the Invention

[0007] Based on this, in order to overcome the problems of low gallium enrichment efficiency and difficult gallium-iron separation in existing pressurized wet zinc smelting solutions, this invention provides a method for efficiently enriching gallium and separating iron from pressurized wet zinc smelting solutions, thereby improving the gallium enrichment and achieving effective gallium separation.

[0008] A method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution includes the following steps:

[0009] Fe 2+ Oxidation: The zinc oxygen pressure leaching solution is oxidized to reduce Fe... 2+ Oxidized to Fe 3+ The first solution was obtained;

[0010] pH adjustment: Add PbO and ZnO to the first solution to adjust the pH to 2.0-2.4 to obtain the second solution;

[0011] Adsorption and precipitation: Activated carbon is added to the second solution, adsorption is performed, and then the solution is filtered to obtain gallium-rich precipitate;

[0012] Zinc leaching with dilute acid: Add H2SO4 to the gallium-rich precipitate to leach zinc and obtain gallium-rich material;

[0013] Cyclic leaching: A strong alkali is added to a portion of the gallium-enriched material for leaching to obtain a gallium alkali leaching solution and iron slag; if the gallium content in the gallium alkali leaching solution is 20-50 g / L, it can be collected; if the gallium content in the gallium alkali leaching solution is less than 20 g / L, it is mixed with another portion of the gallium-enriched material, and a strong alkali is added again for cyclic leaching.

[0014] The zinc-oxygen pressure leaching solution contains the following components: Zn 2+ 150~200g / L, Fe 2+ 10-15 g / L, Fe 3+ 0.1~0.5g / L, H2SO4 10~25g / L, Ga 3+ 10–30 mg / L.

[0015] The chemical reaction equations involved in this invention are as follows:

[0016] Fe 2+ Oxidation: Fe 2+ +O2+4H+→4Fe 3+ +2H2O

[0017] pH adjustment:

[0018] Adsorption and precipitation:

[0019] Circulating leaching:

[0020] Compared with the prior art, the advantages of the present invention are: (1) it achieves deep enrichment of gallium in the zinc leaching solution of pressurized wet zinc smelting without affecting the main process of zinc extraction; (2) it achieves efficient separation of iron and gallium in gallium enrichment; (3) it achieves short-process extraction of gallium in gallium enrichment; (4) the by-product iron slag has a high iron grade and can be used as raw material for blast furnace ironmaking.

[0021] As a preferred embodiment, the Fe 2+ The oxidation method is as follows: Oxygen is introduced at a rate of 0.25–0.5 L / min at 80–90 °C until the Fe in the zinc-oxygen pressure leaching solution is extracted. 3+ Increase the concentration to 1–1.5 g / L, then stop the oxygen flow to obtain the first solution. Increase the Fe concentration.3+ Concentration is beneficial for subsequent Fe 3+ and Ga 3+ Coprecipitation, Fe 3+ Low concentrations can lead to incomplete precipitation, affecting gallium recovery; Fe 3+ High concentrations can lead to excessive precipitation, which in turn reduces the gallium grade.

[0022] As a preferred embodiment, the amount of ZnO added is 66.7% to 333.3% of the PbO, based on the mass of Pb and Zn. A suitable ratio of zinc oxide to lead oxide is beneficial for subsequent gallium enrichment. If there is too little lead oxide, gallium precipitation will be incomplete; if there is too much, the leaching residue will be large, resulting in a low gallium grade in the replacement residue. Zinc oxide is used to adjust the pH to a suitable range without affecting gallium enrichment and the main process zinc extraction.

[0023] As a preferred embodiment, the pH adjustment method is as follows: after adding the PbO and ZnO, react at 80-90℃ for 0.5-3 hours to obtain a second solution.

[0024] As a preferred embodiment, the amount of activated carbon added is 0.2 to 0.4 g / L. If the amount of activated carbon added is too low, the precipitation efficiency will be low or even incomplete precipitation will be impossible, affecting the gallium recovery rate. If the amount of activated carbon added is too high, the amount of precipitation will be too high, which will lead to a decrease in the gallium grade.

[0025] As a preferred embodiment, the adsorption precipitation method involves adding activated carbon, aging the solution at 80–90°C for 2–4 hours, and then filtering to obtain gallium-rich precipitate. Adding activated carbon to assist precipitation effectively reduces the gallium content in the neutralized solution. Furthermore, activated carbon can adsorb free gallium ions in the solution, further improving the gallium recovery rate. This step also yields a neutralized solution, from which zinc can be recovered.

[0026] As a preferred embodiment, the dilute acid zinc leaching method involves adding 0.05–0.1 mol / L H₂SO₄ at a liquid-to-solid ratio of 2.5–5 mL / g at 80–90°C, leaching for 15–30 min to obtain gallium-enriched material. Using dilute sulfuric acid for leaching avoids gallium leaching and prevents a decrease in gallium recovery rate. This step also yields a zinc leaching solution, which can be mixed with a zinc-oxygen pressure leaching solution for recycling.

[0027] As a preferred embodiment, the strong base includes sodium hydroxide.

[0028] As a preferred embodiment, the cyclic leaching method involves adding 1–4 mol / L NaOH at a liquid-to-solid ratio of 2.5–5 mL / g at 80–90°C and leaching for 1–4 hours to obtain a gallium alkali leaching solution and iron slag. Using a strong alkali of appropriate concentration can maximize gallium leaching, improve gallium recovery rate, and reduce losses. Attached Figure Description

[0029] Figure 1 This is a process flow diagram of a method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution. Detailed Implementation

[0030] To further understand the present invention, the present invention will be described in detail below with reference to the embodiments. However, it should be noted that the embodiments do not constitute a limitation on the scope of protection of the present invention.

[0031] A method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution includes the following steps:

[0032] Fe 2+ Oxidation: Oxygen is introduced into the zinc-oxygen pressure leaching solution at a rate of 0.25–0.5 L / min until the Fe in the zinc-oxygen pressure leaching solution... 3+ Increase the concentration to 1-1.5 g / L and stop the oxygen flow to obtain the first solution.

[0033] pH adjustment: Add PbO and ZnO to the first solution to adjust the pH to 2.0-2.4, and react for 0.5-3 hours to obtain the second solution;

[0034] Adsorption and precipitation: Activated carbon is added to the second solution at an amount of 0.2–0.4 g / L. After aging for 2–4 hours, the solution is filtered to obtain gallium-rich precipitate and neutralized solution. Zinc can be recovered from the neutralized solution.

[0035] Zinc leaching with dilute acid: Add 0.05-0.1 mol / L H2SO4 to the gallium-rich precipitate at a liquid-to-solid ratio of 2.5-5 mL / g, and leach for 15-30 min to obtain gallium-rich concentrate and zinc leaching solution; the zinc leaching solution can be mixed with zinc oxygen pressure leaching solution for recycling production;

[0036] Cyclic leaching: Add 1-4 mol / L NaOH to a portion of the gallium-enriched material at a liquid-to-solid ratio of 2.5-5 mL / g, and leach for 1-4 h to obtain gallium alkali leaching solution and iron slag; if the gallium content in the gallium alkali leaching solution is 20-50 g / L, it can be collected; if the gallium content in the gallium alkali leaching solution is less than 20 g / L, it is mixed with another portion of the gallium-enriched material, and NaOH is added again, and leaching is repeated until the gallium content in the gallium alkali leaching solution is 20-50 g / L.

[0037] All of the above steps were carried out at 80–90°C.

[0038] The zinc-oxygen pressure leaching solution described in this embodiment of the invention contains the following components: Zn 2+ 180g / L, Fe 2+ 12g / L, Fe 3+ 0.25 g / L, H2SO4 20 g / L, Ga 3+ 20 mg / L; the amount of ZnO added is 175% of that of PbO, based on the mass of Pb and Zn.

[0039] Example 1

[0040] like Figure 1 As shown, a method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution includes the following steps:

[0041] Fe 2+ Oxidation: At 85℃, oxygen is introduced into the zinc-oxygen pressure leaching solution at a rate of 0.25 L / min until the Fe in the zinc-oxygen pressure leaching solution... 3+ The oxygen supply was stopped when the concentration reached 1 g / L, and the first solution was obtained.

[0042] pH adjustment: PbO and ZnO were added to the first solution to adjust the pH to 2.2. The reaction was carried out at 85℃ for 3 hours to obtain the second solution.

[0043] Adsorption and precipitation: Activated carbon was added to the second solution at a concentration of 0.4 g / L. After aging at 85°C for 4 hours, the solution was filtered to obtain gallium-rich precipitate and neutralized solution. Zinc can be recovered from the neutralized solution.

[0044] Zinc leaching with dilute acid: 0.05 mol / L H2SO4 is added to gallium-rich precipitate at a liquid-to-solid ratio of 5 mL / g, and leaching is carried out at 85°C for 30 min to obtain gallium-rich concentrate and zinc leaching solution; the zinc leaching solution can be mixed with zinc oxygen pressure leaching solution for recycling production.

[0045] Cyclic leaching: Add 2 mol / L NaOH to a portion of the gallium-enriched material at a liquid-to-solid ratio of 5 mL / g, and leach at 85°C for 2 hours to obtain gallium alkali leaching solution and iron slag. If the gallium content in the gallium alkali leaching solution reaches 20 g / L, it can be collected. If the gallium content in the gallium alkali leaching solution is less than 20 g / L, it is mixed with another portion of the gallium-enriched material, and NaOH is added again. Cyclic leaching is carried out until the gallium content in the gallium alkali leaching solution reaches 20 g / L. Then, gallium is recovered by purification-electrolysis.

[0046] Example 2

[0047] A method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution includes the following steps:

[0048] Fe 2+ Oxidation: Oxygen was introduced into the zinc-oxygen pressure leaching solution at a rate of 0.3 L / min at 88 °C until the Fe in the zinc-oxygen pressure leaching solution... 3+ The oxygen supply was stopped when the concentration reached 1.25 g / L, yielding the first solution.

[0049] pH adjustment: PbO and ZnO were added to the first solution to adjust the pH to 2.1. The reaction was carried out at 88℃ for 2.5 h to obtain the second solution.

[0050] Adsorption and precipitation: Activated carbon was added to the second solution at a concentration of 0.3 g / L. After aging at 88°C for 3 hours, the solution was filtered to obtain gallium-rich precipitate and neutralized solution. Zinc can be recovered from the neutralized solution.

[0051] Zinc leaching with dilute acid: 0.08 mol / L H2SO4 is added to gallium-rich precipitate at a liquid-to-solid ratio of 4 mL / g, and leaching is carried out at 88°C for 30 min to obtain gallium-rich concentrate and zinc leaching solution; the zinc leaching solution can be mixed with zinc oxygen pressure leaching solution for recycling production;

[0052] Cyclic leaching: 2.5 mol / L NaOH is added to a portion of the gallium-enriched material at a liquid-to-solid ratio of 4 mL / g, and leaching is carried out at 88°C for 2 hours to obtain gallium alkali leaching solution and iron slag. If the gallium content in the gallium alkali leaching solution reaches 25 g / L, it can be collected. If the gallium content in the gallium alkali leaching solution is less than 25 g / L, it is mixed with another portion of the gallium-enriched material, and NaOH is added again. Cyclic leaching is carried out until the gallium content in the gallium alkali leaching solution reaches 25 g / L. Then, gallium is recovered by purification-electrolysis.

[0053] Example 3

[0054] A method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution includes the following steps:

[0055] Fe 2+ Oxidation: Under conditions of 90℃, oxygen is introduced into the zinc-oxygen pressure leaching solution at a rate of 0.25 L / min until the Fe in the zinc-oxygen pressure leaching solution... 3+ The oxygen supply was stopped when the concentration reached 1.5 g / L, yielding the first solution.

[0056] pH adjustment: PbO and ZnO were added to the first solution to adjust the pH to 2.0. The reaction was carried out at 88℃ for 2 hours to obtain the second solution.

[0057] Adsorption and precipitation: Activated carbon was added to the second solution at a concentration of 0.3 g / L. After aging at 90°C for 2.5 h, the solution was filtered to obtain gallium-rich precipitate and neutralized solution. Zinc can be recovered from the neutralized solution.

[0058] Zinc leaching with dilute acid: 0.1 mol / L H2SO4 is added to gallium-rich precipitate at a liquid-to-solid ratio of 3 mL / g, and leaching is carried out at 90°C for 20 min to obtain gallium-rich concentrate and zinc leaching solution; the zinc leaching solution can be mixed with zinc oxygen pressure leaching solution for recycling production;

[0059] Cyclic leaching: Add 4 mol / L NaOH to a portion of the gallium-enriched material at a liquid-to-solid ratio of 3 mL / g, and leach at 90°C for 2 hours to obtain gallium alkali leaching solution and iron slag. If the gallium content in the gallium alkali leaching solution reaches 30 g / L, it can be collected. If the gallium content in the gallium alkali leaching solution is less than 30 g / L, it is mixed with another portion of the gallium-enriched material, and NaOH is added again. Cyclic leaching is carried out until the gallium content in the gallium alkali leaching solution reaches 30 g / L. Then, gallium is recovered by purification-electrolysis.

[0060] Example 4

[0061] A method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution includes the following steps:

[0062] Fe 2+ Oxidation: Under conditions of 80℃, oxygen is introduced into the zinc-oxygen pressure leaching solution at a rate of 0.5 L / min until the Fe in the zinc-oxygen pressure leaching solution... 3+ The oxygen supply was stopped when the concentration reached 1.5 g / L, yielding the first solution.

[0063] pH adjustment: PbO and ZnO were added to the first solution to adjust the pH to 2.4. The reaction was carried out at 80℃ for 3 hours to obtain the second solution.

[0064] Adsorption precipitation: Activated carbon was added to the second solution at a concentration of 0.2 g / L. After aging at 80°C for 2 hours, the solution was filtered to obtain gallium-rich precipitate and neutralized solution. Zinc can be recovered from the neutralized solution.

[0065] Zinc leaching with dilute acid: 0.1 mol / L H2SO4 is added to gallium-rich precipitate at a liquid-to-solid ratio of 2.5 mL / g, and leaching is carried out at 80°C for 15 min to obtain gallium-rich concentrate and zinc leaching solution; the zinc leaching solution can be mixed with zinc oxygen pressure leaching solution for recycling production.

[0066] Cyclic leaching: 4 mol / L NaOH is added to a portion of the gallium-enriched material at a liquid-to-solid ratio of 2.5 mL / g, and leaching is carried out at 80°C for 4 hours to obtain gallium alkali leaching solution and iron slag. If the gallium content in the gallium alkali leaching solution reaches 40 g / L, it can be collected. If the gallium content in the gallium alkali leaching solution is less than 40 g / L, it is mixed with another portion of the gallium-enriched material, and NaOH is added again. Cyclic leaching is carried out until the gallium content in the gallium alkali leaching solution reaches 40 g / L. Then, gallium is recovered by purification-electrolysis.

[0067] Example 5

[0068] A method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution includes the following steps:

[0069] Fe 2+ Oxidation: Oxygen was introduced into the zinc-oxygen pressure leaching solution at a rate of 0.4 L / min at 83 °C until the Fe in the zinc-oxygen pressure leaching solution... 3+ The oxygen supply was stopped when the concentration reached 1.3 g / L, and the first solution was obtained.

[0070] pH adjustment: PbO and ZnO were added to the first solution to adjust the pH to 2.0. The reaction was carried out at 83℃ for 0.5 h to obtain the second solution.

[0071] Adsorption precipitation: Activated carbon was added to the second solution at a concentration of 0.3 g / L. After aging at 83°C for 2 hours, the solution was filtered to obtain gallium-rich precipitate and neutralized solution. Zinc can be recovered from the neutralized solution.

[0072] Zinc leaching with dilute acid: 0.1 mol / L H2SO4 is added to gallium-rich precipitate at a liquid-to-solid ratio of 5 mL / g, and leaching is carried out at 83°C for 15 min to obtain gallium-rich concentrate and zinc leaching solution; the zinc leaching solution can be mixed with zinc oxygen pressure leaching solution for recycling production.

[0073] Cyclic leaching: Add 2 mol / L NaOH to a portion of the gallium-enriched material at a liquid-to-solid ratio of 3 mL / g, and leach at 83°C for 1 h to obtain gallium alkali leaching solution and iron slag. If the gallium content in the gallium alkali leaching solution reaches 50 g / L, it can be collected. If the gallium content in the gallium alkali leaching solution is less than 50 g / L, it is mixed with another portion of the gallium-enriched material, and NaOH is added again. Cyclic leaching is carried out until the gallium content in the gallium alkali leaching solution reaches 50 g / L. Then, gallium is recovered by purification-electrolysis.

[0074] Comparative Example 1

[0075] No Fe 2+ The oxidation step and other steps are exactly the same as in Example 3.

[0076] Comparative Example 2

[0077] The pH adjustment step uses only zinc oxide; the other steps are exactly the same as in Example 3.

[0078] Comparative Example 3

[0079] The adsorption and precipitation step does not involve the addition of activated carbon; the other steps are exactly the same as in Example 3.

[0080] The results of the examples and comparative examples are shown in Table 1. As can be seen from Table 1, by adjusting Fe... 2+ Oxidation, pH adjustment using lead oxide, and adsorption and precipitation with activated carbon can effectively achieve efficient enrichment of gallium. However, if Fe is lacking in these steps... 2+ Oxidation, Pb 2+ Furthermore, when activated carbon assists in adsorption and precipitation, the gallium concentration in the neutralized solution increases significantly, which is not conducive to the efficient enrichment of gallium during the pressurized wet zinc smelting process.

[0081] Table 1 Results of Examples and Comparative Examples

[0082] <![CDATA[Neutralized solution Ga 3+ Concentration (mg / L)]]> <![CDATA[Ga 3+ Recovery rate (%) Iron content of iron slag (wt%) Example 1 1 95 65.8 Example 2 0.5 97.5 67.2 Example 3 0.25 98.75 68.3 Example 4 0.2 99 68.8 Example 5 0.75 96.25 67.4 Comparative Example 1 10 50 65.8 Comparative Example 2 8 60 66.2 Comparative Example 3 5 75 67.3

Claims

1. A method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution, characterized in that, Includes the following steps: Fe 2+ Oxidation: The zinc oxygen pressure leaching solution is oxidized to reduce Fe... 2+ Oxidized to Fe 3+ The first solution was obtained; pH adjustment: Add PbO and ZnO to the first solution to adjust the pH to 2.0-2.4 to obtain the second solution; Adsorption and precipitation: Activated carbon is added to the second solution, adsorption is performed, and then the solution is filtered to obtain gallium-rich precipitate; Zinc leaching with dilute acid: Add H2SO4 to the gallium-rich precipitate to leach zinc and obtain gallium-rich material; Cyclic leaching: A strong alkali is added to a portion of the gallium-enriched material for leaching to obtain a gallium alkali leaching solution and iron slag; if the gallium content in the gallium alkali leaching solution is 20-50 g / L, it can be collected; if the gallium content in the gallium alkali leaching solution is less than 20 g / L, it is mixed with another portion of the gallium-enriched material, and a strong alkali is added again for cyclic leaching. The zinc-oxygen pressure leaching solution contains the following components: Zn 2+ 150~200g / L, Fe 2+ 10-15 g / L, Fe 3+ 0.1~0.5g / L, H2SO4 10~25g / L, Ga 3+ 10–30 mg / L.

2. The method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution according to claim 1, characterized in that, The Fe 2+ The oxidation method is as follows: Oxygen is introduced at a rate of 0.25–0.5 L / min at 80–90 °C until the Fe in the zinc-oxygen pressure leaching solution is extracted. 3+ Increase the concentration to 1-1.5 g / L and stop the oxygen flow to obtain the first solution.

3. The method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution according to claim 1, characterized in that, The amount of ZnO added is 66.7 to 333.3% of the amount of PbO, based on the mass of Pb and Zn.

4. The method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution according to claim 3, characterized in that, The pH adjustment method is as follows: after adding the PbO and ZnO, react at 80-90℃ for 0.5-3 hours to obtain a second solution.

5. The method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution according to claim 1, characterized in that, The amount of activated carbon added is 0.2–0.4 g / L.

6. The method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution according to claim 5, characterized in that... The adsorption precipitation method is as follows: after adding the activated carbon, the mixture is aged at 80-90℃ for 2-4 hours and then filtered to obtain gallium-rich precipitate.

7. The method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution according to claim 1, characterized in that, The method for zinc leaching with dilute acid is as follows: at 80-90°C, add 0.05-0.1 mol / L H2SO4 at a liquid-to-solid ratio of 2.5-5 mL / g, and leach for 15-30 min to obtain gallium-enriched material.

8. The method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution according to claim 1, characterized in that, The strong base includes sodium hydroxide.

9. The method for efficiently enriching gallium and separating iron from a pressurized wet zinc smelting solution according to claim 8, characterized in that, The cyclic leaching method is as follows: at 80-90℃, add 1-4 mol / L NaOH at a liquid-to-solid ratio of 2.5-5 mL / g and leach for 1-4 h to obtain gallium alkali leaching solution and iron slag.

Images