Method for extracting valuable metals from nickel laterite ore pickle liquor

Abstract

The invention belongs to the technical field of non-ferrous metal hydrometallurgy, and discloses a method for extracting valuable metal from laterite-nickel ore pickle liquor. According to the method, nickel and cobalt can be complexed with ammonia under the ammoniacal condition, and then carbonate is added to selectively separate manganese. For a nickel-cobalt-ammonia solution, an oxidizing agent is used for oxidizing a cobalt-ammonia solution, a divalent cobalt-ammonia complex is oxidized into a trivalent cobalt-ammonia complex, then nickel is masked, and liquid caustic soda is added, so that cobalt can be separated. The remaining nickel complex is oxidized and decomposed under the strong oxidation effect of the unmasking agent to obtain free nickel, then liquid caustic soda is added to separate nickel, and the cracked masking agent is left in the filtrate and can be recycled. The method is easy to operate, easy to industrialize, low in cost and free of environmental pollution, the valuable metal elements in the laterite-nickel ore hydrochloric acid normal-pressure pickle liquor can be extracted in a pure compound product mode, solid waste residues are not generated, valuable metal element resources are fully utilized, and large economic benefits can be generated.

Description

Technical Field

[0001] The invention relates to the technical field of nonferrous metal hydrometallurgy, and in particular to a method for extracting valuable metals from laterite nickel ore acid leaching solution. Background Art

[0002] Nickel is a strategic metal widely used in stainless steel, electronic devices, rechargeable batteries and other fields. About 70% of the world's nickel reserves exist in the form of laterite nickel ore, but only 40% of nickel production comes from laterite nickel ore, and the rest comes from sulfide nickel ore. With the depletion of sulfide nickel deposits and the increase in nickel consumption, researchers are increasingly interested in improving nickel recovery technology from laterite nickel ore, which is a low-grade ore and is often processed by hydrometallurgy or mixed methods. High-pressure acid leaching is a process with high nickel and cobalt recovery rate and low iron leaching rate, but the equipment investment is high, the operating cost is large, and the autoclave is prone to scaling and has high maintenance costs. Atmospheric pressure acid leaching does not require high-pressure equipment and has low investment, but metal elements such as iron, aluminum, manganese, magnesium, and cobalt in laterite nickel ore will enter the acid leaching solution in large quantities. Therefore, effective separation methods must be used to selectively separate these metals from the solution.

[0003] At present, the separation of nickel, cobalt and manganese from laterite nickel ore acid leaching solution is usually carried out by extraction method at home and abroad, using P204 to extract and separate manganese, and P507 to extract and separate nickel and cobalt. However, this method is difficult to completely separate high-content magnesium from nickel and cobalt. In addition, the extractant will remain in the product and the raffinate during use, resulting in an increase in the amount of extractant used, leading to an increase in cost, and it also needs to be degreased, which is not environmentally friendly. Therefore, it is of great significance to explore a process for extracting valuable metals from laterite nickel ore acid leaching solution. Summary of the invention

[0004] The object of the present invention is to provide a method for extracting valuable metals from laterite nickel ore acid leaching solution, so as to solve the problems existing in the existing extraction method for separating nickel, cobalt and manganese in laterite nickel ore acid leaching solution.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for extracting valuable metals from laterite nickel ore acid leaching solution, comprising the following steps:

[0007] (1) Extracting manganese: adding ammonia water to the acid leaching solution of laterite nickel ore to adjust the pH to alkaline, then adding carbonate, and obtaining a manganese-containing product and a nickel-cobalt-containing filtrate after solid-liquid separation;

[0008] (2) Extracting cobalt: adding an oxidant, a masking agent and liquid alkali to the nickel-cobalt filtrate in sequence, and obtaining a cobalt-containing product and a nickel-containing filtrate after solid-liquid separation;

[0009] (3) Extraction of nickel: Add a masking agent and liquid alkali to the nickel-containing filtrate in sequence, and obtain a nickel-containing product and a masking agent-containing filtrate after solid-liquid separation.

[0010] Preferably, in the above method for extracting valuable metals from laterite nickel ore acid leaching solution, the laterite nickel ore acid leaching solution is a filtrate after iron, aluminum and magnesium are removed; the components of the laterite nickel ore acid leaching solution include: Ni 2+ 0.5~40g / L, Co 2 + 0.02~10g / L, Mn 2+ 0.5~5g / L, Na + 0.005~0.1g / L, K + 0.002~0.2g / L.

[0011] Preferably, in the above method for extracting valuable metals from laterite nickel ore acid leaching solution, the carbonate is one or more of sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, ammonium carbonate and ammonium bicarbonate.

[0012] Preferably, in the above method for extracting valuable metals from laterite nickel ore acid leaching solution, the carbonate, Mn in the laterite nickel ore acid leaching solution 2+ The molar ratio is 1 to 1.5:1.

[0013] Preferably, in the above method for extracting valuable metals from laterite nickel ore acid leaching solution, the oxidant is one or more of sodium peroxide, potassium peroxide, hydrogen peroxide, oxygen and ozone.

[0014] Preferably, in the above-mentioned method for extracting valuable metals from laterite nickel ore acid leaching solution, the masking agent is one or more of DTPA (diethylenetriaminepentaacetic acid), EDTA (ethylenediaminetetraacetic acid), EGTA (ethylene glycol bis-α-aminoethyl ether tetraacetic acid), and HEDTA (N-hydroxyethylethylenediaminetriacetic acid).

[0015] Preferably, in the above method for extracting valuable metals from laterite nickel ore acid leaching solution, the oxidant, Co in the laterite nickel ore acid leaching solution 2+ The molar ratio of the masking agent and the nickel laterite leaching solution is 1.05 to 1.3:1; 2+ The molar ratio is 1 to 1.2:1.

[0016] Preferably, in the above method for extracting valuable metals from laterite nickel ore acid leaching solution, the pH value is adjusted to 7.5-10 by adding liquid alkali in step (2); and the pH value is adjusted to 10-12 by adding liquid alkali in step (3).

[0017] Preferably, in the above method for extracting valuable metals from laterite nickel ore acid leaching solution, the demasking agent, Ni in the laterite nickel ore acid leaching solution 2+ The molar ratio is 1 to 1.5:1.

[0018] Preferably, in the above method for extracting valuable metals from laterite nickel ore acid leaching solution, the deshielding agent is one or more of sodium peroxide, potassium peroxide and hydrogen peroxide.

[0019] It can be seen from the above technical solution that compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) The present invention uses the fact that nickel and cobalt will form a complex with ammonia under ammonia conditions, and then adds soluble carbonate to selectively separate manganese from the laterite nickel ore acid leaching solution after the removal of iron, aluminum and magnesium. For the remaining nickel-cobalt ammonia solution, a masking agent is used that does not react with trivalent cobalt ammonia complex and forms a more stable complex with nickel ammonia complex. The cobalt ammonia solution is first oxidized by an oxidant to oxidize the divalent cobalt ammonia complex into a trivalent cobalt ammonia complex, and then nickel is masked, and liquid alkali is added to separate cobalt. The remaining nickel complex is oxidized and decomposed into free nickel under the strong oxidizing action of the masking agent, and liquid alkali is added to separate the nickel, and the cracked masking agent is left in the filtrate and can be recycled.

[0021] (2) The method of the present invention is simple to operate, easy to industrialize, low in cost, and does not pollute the environment. It can extract the valuable metal elements in the hydrochloric acid atmospheric pressure acid leaching solution of laterite nickel ore in the form of simple compound products without generating solid waste residues, making full use of the valuable metal element resources, and generating greater economic benefits. DETAILED DESCRIPTION

[0022] The present invention provides a method for extracting valuable metals from laterite nickel ore acid leaching solution, comprising the following steps:

[0023] (1) Extracting manganese: adding ammonia water to the acid leaching solution of laterite nickel ore to adjust the pH to alkaline, then adding carbonate, and obtaining a manganese-containing product and a nickel-cobalt-containing filtrate after solid-liquid separation;

[0024] (2) Extracting cobalt: adding an oxidant, a masking agent and liquid alkali to the nickel-cobalt filtrate in sequence, and obtaining a cobalt-containing product and a nickel-containing filtrate after solid-liquid separation;

[0025] (3) Extraction of nickel: Add a masking agent and liquid alkali to the nickel-containing filtrate in sequence, and obtain a nickel-containing product and a masking agent-containing filtrate after solid-liquid separation.

[0026] In the present invention, the laterite nickel ore acid leaching solution is preferably the filtrate after the removal of iron, aluminum and magnesium; the components of the laterite nickel ore acid leaching solution include: Ni 2+ 0.5~40g / L, Co 2+0.02~10g / L, Mn 2+ 0.5~5g / L, Na + 0.005~0.1g / L, K + 0.002~0.2g / L.

[0027] In the present invention, the pH value of the mixture adjusted by adding ammonia water in step (1) is preferably 8 to 11, more preferably 8.5 to 10, and even more preferably 9.

[0028] In the present invention, the carbonate is preferably one or more of sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, ammonium carbonate, and ammonium bicarbonate, more preferably one or more of sodium carbonate, potassium carbonate, and ammonium carbonate, and more preferably sodium carbonate.

[0029] In the present invention, the Mn in the carbonate and laterite nickel ore acid leaching solution is 2+ The molar ratio of is preferably 1 to 1.5:1, more preferably 1.1 to 1.3:1, and even more preferably 1.2:1.

[0030] In the present invention, the oxidant is preferably one or more of sodium peroxide, potassium peroxide, hydrogen peroxide, oxygen, and ozone, more preferably sodium peroxide or hydrogen peroxide, and more preferably hydrogen peroxide.

[0031] In the present invention, the masking agent is preferably one or more of DTPA, EDTA, EGTA, and HEDTA, more preferably one or more of DTPA, EDTA, and EGTA, and more preferably DTPA.

[0032] In the present invention, the oxidant, Co in the laterite nickel ore acid leaching solution 2+ The molar ratio of is preferably 1.05 to 1.3:1, more preferably 1.1 to 1.2:1, and even more preferably 1.1:1.

[0033] In the present invention, the masking agent, Ni in the laterite nickel ore acid leaching solution 2+ The molar ratio of is preferably 1 to 1.2:1, more preferably 1.1 to 1.2:1, and even more preferably 1.2:1.

[0034] In the present invention, the pH value adjusted by adding liquid alkali in step (2) is preferably 7.5 to 10, more preferably 9 to 10, and even more preferably 10.

[0035] In the present invention, the pH value adjusted by adding liquid alkali in step (3) is preferably 10 to 12, more preferably 11 to 12, and even more preferably 12.

[0036] In the present invention, the deblocking agent is preferably one or more of sodium peroxide, potassium peroxide, and hydrogen peroxide, more preferably sodium peroxide or potassium peroxide, and more preferably potassium peroxide.

[0037] In the present invention, the demasking agent and the Ni in the laterite nickel ore acid leaching solution are 2+ The molar ratio of is preferably 1 to 1.5:1, more preferably 1.1 to 1.2:1, and even more preferably 1.1:1.

[0038] In the present invention, the masking agent-containing filtrate is recycled to step (2).

[0039] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] Example 1

[0041] This embodiment provides a method for extracting valuable metals from a laterite nickel ore acid leaching solution, comprising the following steps:

[0042] (1) The main components of the laterite nickel ore acid leaching solution after the removal of iron, aluminum and magnesium are: Ni 2+ 19.47g / L, Co 2+ 0.41g / L, Mn 2+ 3.09g / L, Na + 0.029g / L, K + 0.017g / L, add ammonia water to the laterite nickel ore acid leaching solution to adjust the pH to 8.5 to complex nickel and cobalt, then add sodium carbonate to selectively precipitate manganese, sodium carbonate and Mn in the laterite nickel ore acid leaching solution 2+ The molar ratio of is 1.1:1, the manganese precipitation rate can reach 99%, and after solid-liquid separation, manganese-containing product and nickel-cobalt-containing filtrate are obtained;

[0043] (2) Extraction of cobalt: Hydrogen peroxide is added to the nickel-cobalt filtrate to oxidize the divalent cobalt ammonia complex into a trivalent cobalt ammonia complex. The hydrogen peroxide reacts with the Co in the laterite nickel ore acid leaching solution to form a cobalt trivalent complex. 2+ The molar ratio of EGTA to nickel is 1.1:1, and EGTA is added as a nickel masking agent. EGTA reacts with Ni in the laterite nickel ore acid leaching solution. 2+ The molar ratio of 1.1:1 is 1.0:1, and then liquid alkali is added to adjust the pH to 9 to precipitate cobalt, and the cobalt precipitation rate can reach 99.5%. After solid-liquid separation, a cobalt-containing product and a nickel-containing filtrate are obtained;

[0044] (3) Extraction of nickel: Sodium peroxide is added to the nickel-containing filtrate to break the complex. Sodium peroxide reacts with Ni in the laterite nickel ore acid leaching solution.2+ The molar ratio of is 1.1:1, and then liquid alkali is added to adjust the pH to 12 for nickel precipitation, and the nickel precipitation rate can reach 99.2%. After solid-liquid separation, a nickel-containing product and a masking agent-containing filtrate are obtained.

[0045] Example 2

[0046] This embodiment provides a method for extracting valuable metals from a laterite nickel ore acid leaching solution, comprising the following steps:

[0047] (1) The main components of the laterite nickel ore acid leaching solution after the removal of iron, aluminum and magnesium are: Ni 2+ 17.47g / L, Co 2+ 0.33g / L, Mn 2+ 1.09g / L, Na + 0.022g / L, K + 0.011g / L, add ammonia water to the laterite nickel ore acid leaching solution to adjust the pH to 8.5 to complex nickel and cobalt, then add sodium carbonate to selectively precipitate manganese, sodium carbonate and Mn in the laterite nickel ore acid leaching solution 2+ The molar ratio of 1:1, the manganese precipitation rate can reach 98.5%, and after solid-liquid separation, manganese-containing products and nickel-cobalt-containing filtrate are obtained;

[0048] (2) Extraction of cobalt: Sodium peroxide is added to the nickel-cobalt filtrate to oxidize the divalent cobalt ammonia complex into a trivalent cobalt ammonia complex. Sodium peroxide reacts with Co in the laterite nickel ore acid leaching solution to form a cobalt trivalent ammonia complex. 2+ The molar ratio of EDTA to nickel is 1.1:1, and EDTA is added as a nickel masking agent. EDTA reacts with Ni in the laterite nickel ore acid leaching solution. 2+ The molar ratio of 1.2:1 is 1.2:1, and then liquid alkali is added to adjust the pH to 9.5 to precipitate cobalt, and the cobalt precipitation rate can reach 99.6%. After solid-liquid separation, a cobalt-containing product and a nickel-containing filtrate are obtained;

[0049] (3) Extraction of nickel: Sodium peroxide is added to the nickel-containing filtrate to break the complex. Sodium peroxide reacts with Ni in the laterite nickel ore acid leaching solution. 2+ The molar ratio of is 1.2:1, and then liquid alkali is added to adjust the pH to 12 for nickel precipitation, and the nickel precipitation rate can reach 99.8%. After solid-liquid separation, a nickel-containing product and a masking agent-containing filtrate are obtained.

[0050] Example 3

[0051] This embodiment provides a method for extracting valuable metals from a laterite nickel ore acid leaching solution, comprising the following steps:

[0052] (1) The main components of the laterite nickel ore acid leaching solution after the removal of iron, aluminum and magnesium are: Ni 2+ 29.47g / L, Co 2+ 0.51g / L, Mn 2+ 1.81g / L, Na+ 0.039g / L, K + 0.021g / L, add ammonia water to the laterite nickel ore acid leaching solution to adjust the pH to 9 to complex nickel and cobalt, then add sodium carbonate to selectively precipitate manganese, sodium carbonate and Mn in the laterite nickel ore acid leaching solution 2+ The molar ratio of 1.2:1 is 1.2:1, the manganese precipitation rate can reach 99.7%, and after solid-liquid separation, manganese-containing products and nickel-cobalt-containing filtrate are obtained;

[0053] (2) Extraction of cobalt: Hydrogen peroxide is added to the nickel-cobalt filtrate to oxidize the divalent cobalt ammonia complex into a trivalent cobalt ammonia complex. The hydrogen peroxide reacts with the Co in the laterite nickel ore acid leaching solution to form a cobalt trivalent complex. 2+ The molar ratio of DTPA to nickel is 1.1:1, and DTPA is added as a nickel masking agent. DTPA reacts with Ni in the laterite nickel ore acid leaching solution. 2+ The molar ratio of 1.2:1 is 1.2:1, and then liquid alkali is added to adjust the pH to 10 to precipitate cobalt, and the cobalt precipitation rate can reach 99.3%. After solid-liquid separation, a cobalt-containing product and a nickel-containing filtrate are obtained;

[0054] (3) Extraction of nickel: Potassium peroxide is added to the nickel-containing filtrate to break the complex. Potassium peroxide reacts with Ni in the laterite nickel ore acid leaching solution. 2+ The molar ratio of is 1.1:1, and then liquid alkali is added to adjust the pH to 12 for nickel precipitation, and the nickel precipitation rate can reach 99.9%. After solid-liquid separation, a nickel-containing product and a masking agent-containing filtrate are obtained.

[0055] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for extracting valuable metals from laterite nickel ore acid leaching solution, characterized in that: The following steps are involved: (1) Extracting manganese: adding ammonia water to the acid leaching solution of laterite nickel ore to adjust the pH to alkaline, then adding carbonate, and obtaining a manganese-containing product and a nickel-cobalt-containing filtrate after solid-liquid separation; (2) Extracting cobalt: adding an oxidant, a masking agent and liquid alkali to the nickel-cobalt filtrate in sequence, and obtaining a cobalt-containing product and a nickel-containing filtrate after solid-liquid separation; (3) Extraction of nickel: Add a masking agent and liquid alkali to the nickel-containing filtrate in sequence, and obtain a nickel-containing product and a masking agent-containing filtrate after solid-liquid separation.

2. The method for extracting valuable metals from laterite nickel ore acid leaching solution according to claim 1, characterized in that: The laterite nickel ore acid leaching solution is the filtrate after iron, aluminum and magnesium are removed; the components of the laterite nickel ore acid leaching solution include: Ni 2+ 0.5~40g / L, Co 2+ 0.02~10g / L, Mn 2+ 0.5~5g / L, Na + 0.005~0.1g / L, K + 0.002~0.2g / L.

3. The method for extracting valuable metals from laterite nickel ore acid leaching solution according to claim 2, characterized in that: The carbonate is one or more of sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, ammonium carbonate and ammonium bicarbonate.

4. A method for extracting valuable metals from laterite nickel ore acid leaching solution according to claim 1 or 3, characterized in that: The Mn content of the carbonate and laterite nickel ore acid leaching solution 2+ The molar ratio is 1 to 1.5:

1.

5. The method for extracting valuable metals from laterite nickel ore acid leaching solution according to claim 4, characterized in that: The oxidant is one or more of sodium peroxide, potassium peroxide, hydrogen peroxide, oxygen and ozone.

6. The method for extracting valuable metals from laterite nickel ore acid leaching solution according to claim 5, characterized in that: The masking agent is one or more of DTPA, EDTA, EGTA and HEDTA.

7. A method for extracting valuable metals from laterite nickel ore acid leaching solution according to claim 1, 5 or 6, characterized in that: The oxidant, Co in the laterite nickel ore acid leaching solution 2+ The molar ratio of the masking agent and the nickel laterite leaching solution is 1.05 to 1.3:1; 2+ The molar ratio is 1 to 1.2:

1.

8. The method for extracting valuable metals from laterite nickel ore acid leaching solution according to claim 7, characterized in that: In step (2), the pH value is adjusted to 7.5-10 by adding liquid caustic soda; and in step (3), the pH value is adjusted to 10-12 by adding liquid caustic soda.

9. The method for extracting valuable metals from laterite nickel ore acid leaching solution according to claim 7, characterized in that: The deshielding agent, Ni in the laterite nickel ore acid leaching solution 2+ The molar ratio is 1 to 1.5:

1.

10. The method for extracting valuable metals from laterite nickel ore acid leaching solution according to claim 9, characterized in that: The deblocking agent is one or more of sodium peroxide, potassium peroxide and hydrogen peroxide.