A combined processing method of laterite nickel ore and nickel matte

Abstract

The present invention provides a combined treatment method of laterite nickel ore and nickel matte, wherein the combined treatment method utilizes the leaching solution of normal pressure acid leaching of laterite nickel ore with high acidity and rich in Fe 3+ The nickel matte is used to neutralize the residual acid in the leaching solution, and the residual acid and Fe in the leaching solution are used to 3+ The strong oxidizing property of the metal enables efficient dissolution of nickel matte, greatly saving processing costs, improving processing efficiency, and realizing the recovery of various products such as sulfur, electrolytic copper, iron phosphate, nickel sulfate, and cobalt sulfate.

Description

Technical Field

[0001] The invention belongs to the technical field of hydrometallurgy and relates to a method for processing laterite nickel ore, and in particular to a method for combining laterite nickel ore with nickel matte. Background Art

[0002] Nickel, cobalt and iron are important elements in new energy vehicle power batteries. Nickel and cobalt are mainly found in ternary power batteries, and iron is an important component in lithium iron phosphate batteries. Driven by the market demand for new energy vehicles, nickel and cobalt raw materials are in short supply and prices are rising. Many battery raw material manufacturers are planning and developing new nickel, cobalt and iron raw materials.

[0003] Laterite nickel ore has been a hot topic of investment for power battery raw material enterprises in recent years. The smelting process of laterite nickel ore is generally divided into two categories: hydrometallurgy and pyrometallurgy. The hydrometallurgy usually adopts high-pressure acid leaching process, which can produce MHP or MSP intermediate products, and the intermediate products are then refined to obtain battery-grade nickel sulfate; the products of pyrometallurgy are usually nickel pig iron, nickel iron, stainless steel, and can also be made into nickel matte of different grades through reduction smelting or converter blowing, and nickel matte can be refined to obtain nickel sulfate.

[0004] CN111424167A discloses a method for processing laterite nickel ore, comprising: (1) pre-treating the laterite nickel ore to obtain laterite nickel ore particles; (2) mixing the laterite nickel ore particles with a reducing agent to obtain a mixed material; (3) pre-reducing the mixed material to obtain roasted sand; (4) smelting the roasted sand, sulfide ore, smelting solvent, fuel and oxygen-enriched air to obtain a first low-nickel matte and smelting slag; (5) blowing and slagging the first low-nickel matte and blowing solvent to obtain high-nickel matte and blowing slag.

[0005] CN111378851A discloses a system and method for processing laterite nickel ore, which system includes: a pretreatment unit having a laterite nickel ore inlet and a laterite nickel ore particle outlet; a mixing pelletizing device having a laterite nickel ore particle inlet, a reducing agent inlet, a sulfiding agent inlet and a mixed pellet outlet; a pre-reduction sulfiding device having a mixed pellet inlet and a roasted sand outlet; a smelting device having a roasted sand inlet, a smelting solvent inlet, a fuel inlet, an oxygen-enriched air inlet, a first low-nickel matte outlet and a smelting slag outlet; a blowing device having a first low-nickel matte inlet, a blowing solvent inlet, a high-nickel matte outlet and a blowing slag outlet.

[0006] CN114350977A discloses a method for extracting nickel and cobalt from laterite nickel ore by cyclic sulfidation, comprising the following steps: (1) crushing the laterite nickel ore and roasting it to obtain a roasting product; (2) smelting the roasting product and a sulfiding agent, a reducing agent, and a slag-type conditioning agent to form a furnace charge to obtain low-grade nickel matte, thereby achieving nickel and cobalt enrichment; blowing the low-grade nickel matte to obtain cobalt-rich high-grade nickel matte, and then separating nickel and cobalt by a wet method; (3) adding a sulfiding agent and a reducing agent to the hot blowing slag, re-smelting it to obtain cobalt-rich nickel matte, and performing a blowing process; (4) collecting the high-temperature flue gas generated by the smelting system, roasting the laterite nickel ore, and preparing a circulating sulfidation medium by emulsification desulfurization of the flue gas after roasting, and returning it to the smelting system.

[0007] The above methods only process laterite nickel ore, and whether it is a pyrometallurgical process or a hydrometallurgical process, iron is usually treated as an impurity and discarded during the nickel refining process, which undoubtedly causes a waste of resources. The actual application of atmospheric pressure acid leaching of laterite nickel ore is relatively rare, mainly because the temperature is relatively low and it involves the co-leaching of impurity iron, and a very high acidity is required to achieve the ideal nickel leaching effect. The high acidity and high iron content of the solution will undoubtedly lead to huge costs for subsequent neutralization and impurity removal.

[0008] The main components of nickel matte are sulfide eutectics and alloy elements of nickel, iron and copper. The dissolution of low-valent metals requires oxidants. The commonly used processes for wet smelting include sulfuric acid oxygen pressure leaching, chlorine leaching, oxygen pressure ammonia leaching, etc. All three processes require the use of pressurized equipment, and chlorine and ammonia are toxic gases. If not properly stored, leakage accidents are very likely to occur.

[0009] If laterite nickel ore and nickel matte can be processed in a coordinated manner, not only can the laterite nickel ore be recovered, but also the defects caused by nickel matte processing can be reduced. Therefore, it is necessary to provide a method for the combined processing of laterite nickel ore and nickel matte. Summary of the invention

[0010] In view of the shortcomings of the prior art, the present invention aims to provide a method for the combined treatment of laterite nickel ore and nickel matte, wherein the combined treatment method utilizes the high acid and Fe-rich leaching solution of normal pressure acid leaching of laterite nickel ore. 3+ The nickel matte is used to neutralize the residual acid in the leaching solution, and the residual acid and Fe in the leaching solution are used to 3+ The strong oxidizing property of the metal enables efficient dissolution of nickel matte, greatly saving processing costs, improving processing efficiency, and realizing the recovery of various products such as sulfur, electrolytic copper, iron phosphate, nickel sulfate, and cobalt sulfate.

[0011] To achieve this object, the present invention adopts the following technical solutions:

[0012] The present invention provides a combined treatment method of laterite nickel ore and nickel matte, the combined treatment method comprising the following steps:

[0013] (1) slurrying the laterite nickel ore and performing normal pressure acid leaching, and performing solid-liquid separation on the obtained slurry to obtain a first leachate;

[0014] (2) mixing the nickel matte with the first leachate obtained in step (1) to prepare a slurry and react, and performing solid-liquid separation on the slurry after the reaction to obtain crude sulfur and a second leachate;

[0015] (3) subjecting the second leaching solution obtained in step (2) to electrolytic copper removal to obtain a crude electrolytic copper product and a copper-removed solution;

[0016] (4) mixing an oxidant, a phosphorus source, a precipitant and the copper-removed liquid obtained in step (3) to carry out a precipitation reaction; and performing solid-liquid separation on the slurry after the precipitation reaction to obtain iron phosphate and the precipitated liquid;

[0017] (5) The precipitated liquid obtained in step (4) is subjected to extraction, separation and crystallization to obtain battery-grade nickel sulfate and battery-grade cobalt sulfate.

[0018] The combined treatment method of the present invention utilizes the high acid and Fe-rich leaching solution of the normal pressure acid leaching of laterite nickel ore. 3+ The nickel matte is used to neutralize the residual acid in the leaching solution, and the residual acid and Fe in the leaching solution are used to 3+ The strong oxidizing property of the metal enables efficient dissolution of nickel matte, greatly saving processing costs, improving processing efficiency, and realizing the recovery of various products such as sulfur, electrolytic copper, iron phosphate, nickel sulfate, and cobalt sulfate.

[0019] Preferably, the mass ratio of the amount of water added in the slurry preparation in step (1) to the laterite nickel ore is (2-6):1, for example, it can be 2:1, 3:1, 4:1, 5:1 or 6:1, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0020] Preferably, the acid used in the atmospheric pressure acid leaching in step (1) comprises sulfuric acid.

[0021] Preferably, based on the dry ore mass and the sulfuric acid concentration of 98wt%, the mass ratio of the amount of sulfuric acid added for the atmospheric pressure acid leaching in step (1) to the laterite nickel ore is (1-2):1, for example, it can be 1:1, 1.2:1, 1.5:1, 1.6:1, 1.8:1 or 2:1, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0022] Preferably, the temperature of the atmospheric pressure acid leaching in step (1) is 60-100°C, for example, 60°C, 70°C, 80°C, 90°C or 100°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0023] Preferably, the time of the atmospheric pressure acid leaching in step (1) is 2-6 hours, for example, 2 hours, 3 hours, 4 hours, 5 hours or 6 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0024] Preferably, the reaction temperature in step (2) is 60-100° C. and the reaction time is 1-4 h.

[0025] The reaction temperature of step (2) of the present invention is 60-100°C, for example, 60°C, 70°C, 80°C, 90°C or 100°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0026] The reaction time of step (2) of the present invention is 1-4 h, for example, 1 h, 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h or 4 h, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0027] Preferably, in step (2), the mass ratio of the first leaching solution to nickel matte is (5-20):1, for example, it can be 5:1, 8:1, 10:1, 12:1, 15:1, 16:1, 18:1 or 20:1, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0028] Preferably, the pH value of the copper removal by electrowinning in step (3) is 0.5-2, for example, 0.5, 0.8, 1, 1.2, 1.5, 1.8 or 2, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0029] Preferably, the current density of the copper removal by electrowinning in step (3) is 200-500A / m 2 , for example, it can be 200A / m 2 , 250A / m 2 、300A / m 2 、350A / m 2 , 400A / m 2 , 450A / m 2 or 500A / m 2 , but not limited to the listed values, other unlisted values ​​within the numerical range are also applicable.

[0030] Preferably, the residence time of the electrolytic copper removal in step (3) is 2-10 h, for example, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h or 10 h, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0031] Preferably, the oxidant in step (4) comprises any one of hydrogen peroxide, sodium hypochlorite, sodium chlorate or compressed air, or a combination of at least two thereof. Typical but non-limiting combinations include a combination of hydrogen peroxide and sodium hypochlorite, a combination of sodium sulfate and compressed air, a combination of sodium hypochlorite and compressed air, a combination of hydrogen peroxide, sodium hypochlorite and sodium chlorate, a combination of sodium hypochlorite, sodium chlorate and compressed air, or a combination of hydrogen peroxide, sodium hypochlorite, sodium chlorate and compressed air.

[0032] Preferably, the phosphorus source in step (4) comprises any one of phosphoric acid, sodium dihydrogen phosphate or disodium hydrogen phosphate, or a combination of at least two thereof. Typical but non-limiting combinations include a combination of phosphoric acid and sodium dihydrogen phosphate, a combination of sodium dihydrogen phosphate and disodium hydrogen phosphate, or a combination of phosphoric acid, sodium dihydrogen phosphate and disodium hydrogen phosphate.

[0033] Preferably, the precipitant in step (4) comprises sodium hydroxide.

[0034] Preferably, the amount of the oxidant added in step (4) is to reduce the Fe 2+ All oxidized to Fe 3+ .

[0035] Preferably, the molar ratio of P in the phosphorus source in step (4) to Fe in the second leachate is (1-1.1):1, for example, 1:1, 1.03:1, 1.05:1, 1.08:1 or 1.1:1, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0036] Preferably, the amount of the precipitant added in step (4) is to control the pH value of the precipitation reaction to be 1.5-2, for example, it can be 1.5, 1.6, 1.8, 1.9 or 2, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0037] Preferably, the temperature of the precipitation reaction in step (4) is 50-100°C, for example, 50°C, 60°C, 70°C, 80°C, 90°C or 100°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0038] Preferably, the precipitation reaction time in step (4) is 0.5-4 h, for example, 0.5 h, 1 h, 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h or 4 h, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0039] Preferably, the extractant used for the extraction and separation in step (5) includes any one of P204, P507 or Cyanex272, or a combination of at least two of them. Typical but non-limiting combinations include a combination of P204 and P507, a combination of P507 and Cyanex272, a combination of P204 and Cyanex272, or a combination of P204, P507 and Cyanex272.

[0040] As a preferred technical solution of the combined treatment method of the present invention, the combined treatment method comprises the following steps:

[0041] (1) preparing a slurry of laterite nickel ore, and performing atmospheric pressure acid leaching at 60-100° C. for 2-6 hours, and performing solid-liquid separation on the obtained slurry to obtain a first leachate; the mass ratio of the amount of water added for the slurry preparation to the laterite nickel ore is (2-6):1; the acid used for the atmospheric pressure acid leaching includes sulfuric acid; based on the dry ore mass and the sulfuric acid concentration of 98wt%, the mass ratio of the sulfuric acid used for the atmospheric pressure acid leaching to the laterite nickel ore is (1-2):1

[0042] (2) mixing nickel matte with the first leachate obtained in step (1) to prepare a slurry, and reacting the mixture at 60-100° C. for 1-4 hours. The slurry after the reaction is solid-liquid separated to obtain crude sulfur and a second leachate; the mass ratio of the first leachate to nickel matte is (5-20):1;

[0043] (3) The second leaching solution obtained in step (2) is subjected to electrolytic copper removal to obtain a crude electrolytic copper product and a copper-removed solution; the pH value of the electrolytic copper removal is 0.5-2, and the current density is 200-500A / m 2 , the residence time is 2-10h;

[0044] (4) mixing an oxidant, a phosphorus source, a precipitant and the copper-removed liquid obtained in step (3) and performing a precipitation reaction at 50-100° C. for 0.5-4 h; performing solid-liquid separation on the slurry after the precipitation reaction to obtain iron phosphate and a precipitated liquid; the amount of the oxidant added is such that the Fe in the copper-removed liquid is reduced to 2+ All oxidized to Fe 3+ ; The molar ratio of P in the phosphorus source to Fe in the second leaching solution is (1-1.1):1; the amount of the precipitant added is to control the pH value of the precipitation reaction to be 1.5-2;

[0045] (5) The precipitated liquid obtained in step (4) is subjected to extraction, separation and crystallization to obtain battery-grade nickel sulfate and battery-grade cobalt sulfate.

[0046] The numerical range described in the present invention not only includes the point values ​​listed above, but also includes any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] The combined treatment method of the present invention utilizes the high acid and Fe-rich leaching solution of the normal pressure acid leaching of laterite nickel ore. 3+ The nickel matte is used to neutralize the residual acid in the leaching solution, and the residual acid and Fe in the leaching solution are used to 3+ The strong oxidizing property of the metal enables efficient dissolution of nickel matte, greatly saving processing costs, improving processing efficiency, and realizing the recovery of various products such as sulfur, electrolytic copper, iron phosphate, nickel sulfate, and cobalt sulfate. DETAILED DESCRIPTION

[0049] The technical solution of the present invention is further illustrated below through specific implementation methods.

[0050] In order to clearly illustrate the technical solution of the present invention, the laterite nickel ore of the present invention is purchased from a foreign laterite nickel ore area, and its composition includes: 0.12wt% Co, 1.35wt% Ni, 42wt% Fe and 0.01wt% Cu;

[0051] The nickel matte was purchased from a nickel matte manufacturer, and its composition includes 3wt% Co, 65wt% Ni, 10wt% Fe, 3wt% Cu and 18wt% S.

[0052] The composition of the above-mentioned laterite nickel ore and nickel matte is to further clearly illustrate the technical solution of the present invention and should not be regarded as a further limitation of the laterite nickel ore and nickel matte.

[0053] Example 1

[0054] This embodiment provides a method for jointly processing laterite nickel ore and nickel matte, and the combined processing method comprises the following steps:

[0055] (1) The laterite nickel ore is slurried and subjected to atmospheric pressure acid leaching at 80° C. for 4 h, and the obtained slurry is subjected to solid-liquid separation to obtain a first leachate; the mass ratio of the amount of water added for the slurry to the laterite nickel ore is 4:1; the acid used for the atmospheric pressure acid leaching includes sulfuric acid; based on the dry ore mass and the sulfuric acid concentration of 98wt%, the mass ratio of the sulfuric acid used for the atmospheric pressure acid leaching to the laterite nickel ore is 1.5:1

[0056] (2) mixing the nickel matte with the first leachate obtained in step (1) to prepare a slurry, and reacting the mixture at 80° C. for 2 h. The slurry after the reaction is solid-liquid separated to obtain crude sulfur and a second leachate; the mass ratio of the first leachate to the nickel matte is 10:1;

[0057] (3) The second leaching solution obtained in step (2) is subjected to electrolytic copper removal to obtain a crude electrolytic copper product and a copper-removed solution; the pH value of the electrolytic copper removal is 1, and the current density is 350A / m 2 , the residence time is 6h;

[0058] (4) mixing an oxidant (sodium hypochlorite), a phosphorus source (sodium dihydrogen phosphate), and a precipitant (sodium hydroxide) with the copper-removed liquid obtained in step (3), and performing a precipitation reaction at 80° C. for 2 h; performing solid-liquid separation on the slurry after the precipitation reaction to obtain iron phosphate and a precipitated liquid; the amount of the oxidant added is such that the Fe in the copper-removed liquid is reduced to 2+ All oxidized to Fe 3+ ; The molar ratio of P in the phosphorus source to Fe in the second leaching solution is 1.05:1; the amount of the precipitant added is to control the pH value of the precipitation reaction to be 1.8;

[0059] (5) The precipitated liquid obtained in step (4) is subjected to extraction separation and crystallization to obtain battery-grade nickel sulfate and battery-grade cobalt sulfate; the extractants used for the extraction separation are P204 and P507.

[0060] The combined treatment method provided in this embodiment utilizes the high acid and Fe-rich leaching solution of the atmospheric pressure acid leaching of laterite nickel ore. 3+ The nickel matte is used to neutralize the residual acid in the leaching solution, and the residual acid and Fe in the leaching solution are used to 3+ The strong oxidizing property of the metal enables efficient dissolution of nickel matte, greatly saving processing costs, improving processing efficiency, and realizing the recovery of various products such as sulfur, electrolytic copper, iron phosphate, nickel sulfate, and cobalt sulfate.

[0061] Example 2

[0062] This embodiment provides a method for jointly processing laterite nickel ore and nickel matte, and the combined processing method comprises the following steps:

[0063] (1) The laterite nickel ore is slurried and subjected to atmospheric pressure acid leaching at 60° C. for 6 h, and the obtained slurry is subjected to solid-liquid separation to obtain a first leachate; the mass ratio of the amount of water added for the slurry to the laterite nickel ore is 2:1; the acid used for the atmospheric pressure acid leaching includes sulfuric acid; based on the dry ore mass and the sulfuric acid concentration of 98wt%, the mass ratio of the sulfuric acid used for the atmospheric pressure acid leaching to the laterite nickel ore is 1:1

[0064] (2) mixing the nickel matte with the first leachate obtained in step (1) to prepare a slurry, and reacting the mixture at 60° C. for 4 h. The slurry after the reaction is solid-liquid separated to obtain crude sulfur and a second leachate; the mass ratio of the first leachate to the nickel matte is 5:1;

[0065] (3) The second leaching solution obtained in step (2) is subjected to electrolytic copper removal to obtain a crude electrolytic copper product and a copper-removed solution; the pH value of the electrolytic copper removal is 0.5, and the current density is 200A / m 2 , the residence time is 10h;

[0066] (4) mixing an oxidant (hydrogen peroxide), a phosphorus source (disodium hydrogen phosphate), and a precipitant (sodium hydroxide) with the copper-removed liquid obtained in step (3), and performing a precipitation reaction at 50° C. for 4 h; performing solid-liquid separation on the slurry after the precipitation reaction to obtain iron phosphate and a precipitated liquid; the amount of the oxidant added is such that the Fe in the copper-removed liquid is reduced to 2+ All oxidized to Fe 3+ ; The molar ratio of P in the phosphorus source to Fe in the second leaching solution is 1:1; the amount of the precipitant added is to control the pH value of the precipitation reaction to 2;

[0067] (5) The precipitated liquid obtained in step (4) is subjected to extraction separation and crystallization to obtain battery-grade nickel sulfate and battery-grade cobalt sulfate; the extractants used for the extraction separation are P507 and Cyanex272.

[0068] The combined treatment method provided in this embodiment utilizes the high acid and Fe-rich leaching solution of the atmospheric pressure acid leaching of laterite nickel ore. 3+ The nickel matte is used to neutralize the residual acid in the leaching solution, and the residual acid and Fe in the leaching solution are used to 3+ The strong oxidizing property of the metal enables efficient dissolution of nickel matte, greatly saving processing costs, improving processing efficiency, and realizing the recovery of various products such as sulfur, electrolytic copper, iron phosphate, nickel sulfate, and cobalt sulfate.

[0069] Example 3

[0070] This embodiment provides a method for jointly processing laterite nickel ore and nickel matte, and the combined processing method comprises the following steps:

[0071] (1) The laterite nickel ore is slurried and subjected to atmospheric pressure acid leaching at 90° C. for 2 h, and the obtained slurry is subjected to solid-liquid separation to obtain a first leachate; the mass ratio of the amount of water added for the slurry to the laterite nickel ore is 6:1; the acid used for the atmospheric pressure acid leaching includes sulfuric acid; based on the dry ore mass and the sulfuric acid concentration of 98wt%, the mass ratio of the sulfuric acid used for the atmospheric pressure acid leaching to the laterite nickel ore is 2:1

[0072] (2) mixing the nickel matte with the first leachate obtained in step (1) to prepare a slurry, and reacting the mixture at 90° C. for 1 h. The slurry after the reaction is solid-liquid separated to obtain crude sulfur and a second leachate; the mass ratio of the first leachate to the nickel matte is 20:1;

[0073] (3) The second leaching solution obtained in step (2) is subjected to electrolytic copper removal to obtain a crude electrolytic copper product and a copper-removed solution; the pH value of the electrolytic copper removal is 2, and the current density is 500A / m 2 , the residence time is 2h;

[0074] (4) mixing an oxidant (sodium chlorate), a phosphorus source (phosphoric acid), and a precipitant (sodium hydroxide) with the copper-removed liquid obtained in step (3), and performing a precipitation reaction at 100° C. for 0.5 h; performing solid-liquid separation on the slurry after the precipitation reaction to obtain iron phosphate and a precipitated liquid; the amount of the oxidant added is such that the Fe in the copper-removed liquid is reduced to 2+ All oxidized to Fe 3+ ; The molar ratio of P in the phosphorus source to Fe in the second leaching solution is 1.1:1; the amount of the precipitant added is to control the pH value of the precipitation reaction to be 1.5;

[0075] (5) The precipitated liquid obtained in step (4) is subjected to extraction separation and crystallization to obtain battery-grade nickel sulfate and battery-grade cobalt sulfate; the extractants used for the extraction separation are P204 and Cyanex272.

[0076] The combined treatment method provided in this embodiment utilizes the high acid and Fe-rich leaching solution of the atmospheric pressure acid leaching of laterite nickel ore. 3+ The nickel matte is used to neutralize the residual acid in the leaching solution, and the residual acid and Fe in the leaching solution are used to 3+ The strong oxidizing property of the metal enables efficient dissolution of nickel matte, greatly saving processing costs, improving processing efficiency, and realizing the recovery of various products such as sulfur, electrolytic copper, iron phosphate, nickel sulfate, and cobalt sulfate.

[0077] In summary, the combined treatment method of the present invention utilizes the high acid and Fe-rich leaching solution of laterite nickel ore atmospheric pressure acid leaching 3+ The nickel matte is used to neutralize the residual acid in the leaching solution, and the residual acid and Fe in the leaching solution are used to 3+ The strong oxidizing property of the metal enables efficient dissolution of nickel matte, greatly saving processing costs, improving processing efficiency, and realizing the recovery of various products such as sulfur, electrolytic copper, iron phosphate, nickel sulfate, and cobalt sulfate.

[0078] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for the combined treatment of laterite nickel ore and nickel matte, characterized in that: The combined processing method comprises the following steps: (1) slurrying the laterite nickel ore and performing normal pressure acid leaching, and performing solid-liquid separation on the obtained slurry to obtain a first leachate; The acid used in the atmospheric pressure acid leaching includes sulfuric acid; (2) mixing the nickel matte with the first leachate obtained in step (1) to prepare a slurry and react, and performing solid-liquid separation on the slurry after the reaction to obtain crude sulfur and a second leachate; (3) subjecting the second leaching solution obtained in step (2) to electrolytic copper removal to obtain a crude electrolytic copper product and a copper-removed solution; (4) mixing an oxidant, a phosphorus source, a precipitant and the copper-removed liquid obtained in step (3) to carry out a precipitation reaction; and performing solid-liquid separation on the slurry after the precipitation reaction to obtain iron phosphate and the precipitated liquid; The precipitant includes sodium hydroxide; The amount of the precipitant added is to control the pH value of the precipitation reaction to be 1.5-2; (5) The precipitated liquid obtained in step (4) is subjected to extraction, separation and crystallization to obtain battery-grade nickel sulfate and battery-grade cobalt sulfate.

2. The combined processing method according to claim 1, characterized in that: The mass ratio of the amount of water added in the slurry preparation in step (1) to the laterite nickel ore is (2-6):

1.

3. The combined processing method according to claim 1, characterized in that: Based on the dry ore mass and the sulfuric acid concentration of 98wt%, the mass ratio of the sulfuric acid added in the atmospheric pressure acid leaching in step (1) to the laterite nickel ore is (1-2):

1.

4. The combined treatment method according to claim 1 or 2, characterized in that: The temperature of the normal pressure acid leaching in step (1) is 60-100°C.

5. The combined processing method according to claim 1, characterized in that: The time of the normal pressure acid leaching in step (1) is 2-6 hours.

6. The combined processing method according to claim 1, characterized in that: The reaction temperature of step (2) is 60-100°C and the reaction time is 1-4h.

7. The combined processing method according to claim 1, characterized in that: In step (2), the mass ratio of the first leaching solution to nickel matte is (5-20):

1.

8. The combined processing method according to claim 1, characterized in that: The pH value of the copper removal by electrowinning in step (3) is 0.5-2.

9. The combined processing method according to claim 1, characterized in that: The current density of the copper removal by electrowinning in step (3) is 200-500A / m 2 .

10. The combined processing method according to claim 1, characterized in that: The residence time of the copper removal by electrowinning in step (3) is 2-10 hours.

11. The combined processing method according to claim 1, characterized in that: The oxidant in step (4) includes any one of hydrogen peroxide, sodium hypochlorite, sodium chlorate or compressed air, or a combination of at least two of them.

12. The combined processing method according to claim 1, characterized in that: The phosphorus source in step (4) includes any one of phosphoric acid, sodium dihydrogen phosphate or disodium hydrogen phosphate, or a combination of at least two thereof.

13. The combined processing method according to claim 11, characterized in that: The amount of the oxidant added in step (4) is to reduce the Fe 2+ All oxidized to Fe 3+ .

14. The combined processing method according to claim 1, characterized in that: The molar ratio of P in the phosphorus source in step (4) to Fe in the second leaching solution is (1-1.1):

1.

15. The combined processing method according to claim 1, characterized in that: The temperature of the precipitation reaction in step (4) is 50-100°C.

16. The combined processing method according to claim 1, characterized in that: The precipitation reaction time in step (4) is 0.5-4h.

17. The combined processing method according to claim 1, characterized in that: The extractant used for the extraction separation in step (5) includes any one of P204, P507 or Cyanex272, or a combination of at least two of them.

18. The combined processing method according to claim 1, characterized in that: The combined processing method comprises the following steps: (1) preparing a slurry of laterite nickel ore, and performing atmospheric pressure acid leaching at 60-100° C. for 2-6 hours, and performing solid-liquid separation on the obtained slurry to obtain a first leachate; the mass ratio of the amount of water added for the slurry preparation to the laterite nickel ore is (2-6):1; the acid used for the atmospheric pressure acid leaching includes sulfuric acid; based on the dry ore mass and the sulfuric acid concentration of 98wt%, the mass ratio of the sulfuric acid used for the atmospheric pressure acid leaching to the laterite nickel ore is (1-2):1 (2) mixing nickel matte with the first leachate obtained in step (1) to prepare a slurry, and reacting the mixture at 60-100° C. for 1-4 hours. The slurry after the reaction is solid-liquid separated to obtain crude sulfur and a second leachate; the mass ratio of the first leachate to nickel matte is (5-20):1; (3) The second leaching solution obtained in step (2) is subjected to electrolytic copper removal to obtain a crude electrolytic copper product and a copper-removed solution; the pH value of the electrolytic copper removal is 0.5-2, and the current density is 200-500A / m 2 , the residence time is 2-10h; (4) mixing an oxidant, a phosphorus source, a precipitant and the copper-removed liquid obtained in step (3) and performing a precipitation reaction at 50-100° C. for 0.5-4 h; performing solid-liquid separation on the slurry after the precipitation reaction to obtain iron phosphate and a precipitated liquid; the amount of the oxidant added is such that the Fe in the copper-removed liquid is reduced to 2+ All oxidized to Fe 3+ ; The molar ratio of P in the phosphorus source to Fe in the second leaching solution is (1-1.1):1; the amount of the precipitant added is to control the pH value of the precipitation reaction to be 1.5-2; (5) The precipitated liquid obtained in step (4) is subjected to extraction, separation and crystallization to obtain battery-grade nickel sulfate and battery-grade cobalt sulfate.