CN112662871B

CN112662871B - Cobalt-doped high-pressure cobalt-iron separation method for high-concentration cobalt-iron leaching solution

Info

Publication number: CN112662871B
Application number: CN202011480477.6A
Authority: CN
Inventors: 王斌; 洪涛; 姜俊; 程琛; 邓永贵; 张涛
Original assignee: Quzhou Huayou Cobalt New Material Co ltd; Zhejiang Huayou Cobalt Co Ltd
Current assignee: Quzhou Huayou Cobalt New Material Co ltd; Zhejiang Huayou Cobalt Co Ltd
Priority date: 2020-12-15
Filing date: 2020-12-15
Publication date: 2022-07-08
Anticipated expiration: 2040-12-15
Also published as: CN112662871A

Abstract

The invention discloses a cobalt-doped high-pressure cobalt-iron separation method for a high-concentration cobalt-iron leaching solution. The technical scheme adopted by the invention is as follows: leaching the cobalt-copper-iron-containing raw material by sulfuric acid to prepare a high-concentration cobalt-iron leaching solution; after the high-concentration cobalt-iron leaching solution is diluted to a set concentration, adding a cobalt-containing compound, and fully and uniformly stirring to obtain a cobalt-iron separation front solution; before cobalt and iron separation, the liquid is pumped into a closed high-pressure device, a high-oxygen partial pressure environment is manufactured by pure oxygen, and the liquid is fully reacted under the comprehensive action of stirring, air disturbance and liquid flow; concentrating the liquid after cobalt and iron separation, press filtering, centrifuging to separate solid from liquid, and collecting the solid as ferric oxide powder, and treating the liquid with SO₂Returning to the front end after reduction to be used as a diluent of the high-concentration cobalt-iron leaching solution or entering an extraction system to be used as a cobalt extraction stock solution. The method can realize the rapid separation of elements in the cobalt-iron leaching solution, the obtained iron oxide powder has low impurity content, can be sold as iron concentrate powder, and can realize the full and comprehensive utilization of resources while reducing the environmental protection pressure.

Description

Cobalt-doped high-pressure cobalt-iron separation method for high-concentration cobalt-iron leaching solution

Technical Field

The invention belongs to the technical field of wet metallurgy, and relates to a cobalt-doped high-pressure cobalt-iron separation method for a high-concentration cobalt-iron leaching solution.

Background

The mixture of copper-cobalt-iron oxide, the mixture of hydroxides or the crude copper-cobalt-iron alloy is a common leaching raw material in the cobalt hydrometallurgy industry. The raw materials have the advantages of high content of valuable elements, low content of impurities such as manganese, magnesium and the like, simple production subsequent treatment process, small extraction and impurity removal pressure, small amount of waste water and few types of byproducts. However, part of the raw materials also have the problem of overhigh iron content, and because the properties of cobalt and iron are close, two elements can enter a solution simultaneously during leaching, so that a large amount of mixed leaching solution containing cobalt and iron is generated, and how to efficiently separate cobalt and iron is one of limiting factors for restricting the improvement of cobalt capacity.

Chinese patent publication No. CN106756022A describes a method for removing iron impurities in cobalt hydrometallurgy. The iron is removed by adopting a two-stage neutralization hydrolysis method, the oxidant of air and sulfur dioxide mixed gas is selected for the two-stage iron removal to control the potential, calcium oxide is used as a neutralizer to adjust the pH value, one-stage iron slag is scrapped and opened, and the two-stage iron slag is returned to the one-stage iron removal process, so that the aim of deeply removing the iron in the two-stage iron removal process is fulfilled. The method can realize deep iron removal, but the iron removal by the selected neutralization hydrolysis method can only process the cobalt-iron leaching solution with the total iron content of 0.5-15 g/L, and if the iron removal is performed on the high-iron solution by the neutralization hydrolysis method, colloid precipitate of hydroxide is easily formed in the process, so that the filtering performance is reduced, the loss of valuable metals is large, and the yield is reduced. In addition, the method selects calcium oxide as a neutralizer to adjust the pH value, and a large amount of calcium sulfate insoluble substances are easily formed in the iron removal process, so that the iron removal slag quantity is large, the iron grade is reduced, the content of impurity element sulfur is increased, and the iron slag is difficult to recycle.

Chinese patent publication No. CN106148688A describes a leaching and iron-precipitating process in the field of zinc hydrometallurgy. In the first stage, iron is precipitated by adopting a conventional jarosite method, and calcine and ammonium bicarbonate are added; the second stage adopts ammonium bicarbonate and calcium carbonate, and the obtained iron-removing slag is iron vitriol slag. The method is carried out in two stages, the iron removal process is relatively complicated, in addition, impurity elements such as ammonia nitrogen, calcium and the like are introduced into the iron removal agent, the iron grade (the Fe content is 25%) in the iron removal slag is reduced, and meanwhile, the treatment pressure of subsequent wastewater is increased.

In the field of cobalt hydrometallurgy, the separation of cobalt and iron in acid leaching solution is a relatively difficult work, and the conventional mature iron removal method has certain problems in the treatment of leaching solution with high iron concentration. The neutralization hydrolysis method can generate a large amount of ferric hydroxide colloid, so that liquid-solid separation is difficult to realize, and the adsorption loss of cobalt ions is easy to cause. The goethite method has limited treatment capacity, is generally suitable for treating leachate with iron ion concentration of about 5g/L, and is difficult to implement when the iron ion concentration is higher. The iron vitriol method is suitable for treating leachate with high iron ion concentration, but because the iron vitriol method generates large amount of slag, high sulfur content and low iron content, the slag is difficult to recycle, so that resource waste and waste residue accumulation are caused.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome the defects in the prior art and provide a cobalt-doped high-pressure cobalt-iron separation method for a high-concentration cobalt-iron leaching solution to prepare iron oxide concentrate powder with high iron content and low sulfur content so as to realize comprehensive utilization of iron resources.

Therefore, the invention adopts the following technical scheme: a method for separating cobalt-doped high-pressure cobalt and iron from high-concentration cobalt and iron leachate comprises the following steps:

A. leaching the cobalt-copper-iron-containing raw material by sulfuric acid to prepare a high-concentration cobalt-iron leaching solution;

B. after the high-concentration cobalt-iron leaching solution is diluted to a set concentration, adding a cobalt-containing compound, and fully and uniformly stirring to obtain a cobalt-iron separation front solution;

C. before cobalt and iron separation, the liquid is pumped into a closed high-pressure device, a high-oxygen partial pressure environment is manufactured by pure oxygen, and the liquid is fully reacted under the comprehensive action of stirring, air disturbance and liquid flow;

D. performing liquid-solid separation on the liquid after cobalt-iron separation by adopting the combination of concentration, filter pressing and centrifugation to obtain solid iron oxide powder, and performing SO treatment on the obtained liquid₂Returning to the front end after reduction to be used as a diluent of the high-concentration cobalt iron leaching solution or entering an extraction system to be used as a cobalt extraction stock solution.

The invention takes cobalt-containing compound as cobalt-iron separation accelerant and high oxygen partial pressure environment as separation promoting means, and solves the problem of fully separating cobalt and iron in the leaching solution and generating iron oxide powder with low impurity content, high iron content and uniform granularity.

Further, the raw material containing cobalt, copper and iron is a cobalt-copper-iron oxide mixtureThe sulfuric acid leaching is atmospheric pressure reduction leaching, and the high-concentration cobalt-iron leaching solution contains Co²⁺And Fe²⁺In the sulfate leach liquor of (1), wherein, Co²⁺Ion concentration of 15-60 g/L, Fe²⁺The ion concentration is 50-110 g/L.

Further, the dilution refers to diluting the concentration of iron ions, the dilution ratio is determined according to the initial concentration of the iron ions in the leachate, the set concentration refers to controlling the concentration of the diluted iron ions to be 45-80 g/L, and the concentration of cobalt does not make special requirements.

Further, the diluent is a cobalt-iron separated liquid or tap water.

Further, the cobalt-containing compound is CoO, Co (OH)₂、CoCO₃The addition of the cobalt-containing compound is to promote the separation of cobalt and iron, and the cobalt-containing compound can play a role in robbing sulfate radicals and promoting the hydrolysis and precipitation of iron.

Furthermore, the addition amount of the cobalt-containing compound is 5-60 g/L.

Further, the pH of the pre-cobalt-iron separation solution is 2-5.5, the temperature is 65-70 ℃, and Fe is added²⁺The proportion of the Fe accounts for 93-98 percent of the total Fe.

Furthermore, the closed high-pressure equipment adopts 3 stages of serial connection, each stage of independent stirring is carried out, wherein the 1 st stage is not heated, the temperature is 50-80 ℃, heat comes from the temperature of the cobalt-iron separation front liquid and the relative flow of the gas in the 2 nd stage kettle, the 2 nd stage and the 3 rd stage are heated by a steam coil, and the temperature is maintained at 160-190 ℃.

Furthermore, a high oxygen partial pressure environment is manufactured by utilizing pure oxygen, the oxygen partial pressure is maintained at 0.1-0.6 MPa, oxygen is introduced into the reaction liquid at the bottom of the side wall of the closed high-pressure equipment through a high-pressure pipeline, and each stage of closed high-pressure equipment is provided with 5 oxygen inlets so as to ensure that the reaction can be carried out more efficiently and uniformly.

Further, the liquid after cobalt and iron separation is subjected to pressure relief through a pressure relief device, and the generated steam heat resource returns to the front end to maintain the temperature of the liquid before cobalt and iron separation; the cobalt and iron separated liquid after pressure relief enters into the concentration at the temperature of 60-90 DEG CA thickener, after flocculation and sedimentation, the supernatant fluid realizes liquid-solid separation through filter pressing, the underflow realizes liquid-solid separation through centrifugal separation, the obtained liquid passes through SO₂Reducing to avoid the generation of high-valence metal ions, wherein the obtained solid is ferric oxide powder.

Furthermore, the iron oxide powder contains less than 1wt% of sulfur, 60-65 wt% of iron, less than 10wt% of water and more than 90% of iron oxide with a particle size of 200 meshes.

Compared with the prior art, the invention has the following advantages:

(1) the invention uses CoO, Co (OH)₂Or CoCO₃When the cobalt-containing compound is a cobalt-iron separation promoter, Co produced in the hydrolysis reaction process of iron ions²⁺The ions can rob sulfate radicals in the solution, thereby promoting the hydrolysis reaction of iron ions and precipitating and separating Fe₂O₃The addition of the separation promoter can obviously improve the iron removal limit and iron removal efficiency;

(2) the cobalt-iron separation promoter does not introduce other impurity elements into the solution, can further improve the cobalt concentration in the leaching solution, and is beneficial to reducing the rear-end cobalt extraction cost;

(3) according to the closed high-pressure equipment, oxygen is injected through the plurality of inlets uniformly distributed at the bottom of the side wall, and the oxygen directly rushes into the bottom of the reaction liquid in a dispersion mode to form gas disturbance, so that the stirring efficiency is improved while the gas-liquid contact area and the contact time are increased;

(4) the closed high-pressure equipment adopts 3-level series connection, the solution flows and reacts in the interior, continuous production can be realized, and the gradient temperature is adopted, so that the growth of iron oxide particles is facilitated;

(5) under the comprehensive action of the cobalt-iron separation accelerant and the high-efficiency equipment structure, the invention can prepare high-quality iron oxide powder with iron content of more than 62 percent, sulfur content of less than 1 percent and particle size of more than 90 percent passing through 200 meshes at the temperature of 180 ℃.

Drawings

FIG. 1 is an X-ray diffraction phase analysis (XRD) diagram of a solid slag sample obtained in example 1 of the present invention;

FIG. 2 is a Scanning Electron Microscope (SEM) image of a solid slag sample obtained in example 1 of the present invention;

FIG. 3 is an X-ray diffraction phase analysis (XRD) diagram of a solid slag sample obtained in comparative example 1 of the present invention;

FIG. 4 is a Scanning Electron Micrograph (SEM) of a solid slag sample obtained in comparative example 1 of the present invention.

Detailed Description

The technical scheme of the invention is further explained by the specific implementation mode through the accompanying drawings of the specification. It should be understood by those skilled in the art that the examples described are only for the aid of understanding the present invention and should not be construed as specifically limiting the present invention.

Some, but not all embodiments of the invention are intended to cover all alternative embodiments, which can be devised by those skilled in the art based on the embodiments of the invention without any creative effort.

Example 1

Leaching a certain cobalt-copper-iron alloy material by sulfuric acid at 80 ℃ to obtain high-concentration leachate containing 103g/L of iron and 18g/L of cobalt, diluting the leachate to be 1.6 times of the volume of the leachate by using the solution after iron removal to obtain diluted leachate containing 65g/L of iron and 32g/L of cobalt, adding Co (OH) according to the concentration of 50g/L₂The addition of the separation promoter was 27.8 g/L. Thus, a cobalt-iron pre-separation solution having a pH of 4.36 was obtained. Continuously pumping the solution into a closed high-pressure device, reacting in an oxygen partial pressure environment of 0.3MPa at 180 ℃, controlling the flux speed of the liquid, enabling the solution to flow in the high-pressure device for reaction for about 2 hours, after the reaction is finished, releasing the pressure of the solution after cobalt and iron are separated through a pressure relief device, and returning the generated steam heat resource to the front end for maintaining the temperature of the iron removal front liquid. The liquid after iron removal after pressure relief enters a thickener at 82 ℃, after flocculation and sedimentation, liquid-solid separation is realized by filter pressing of supernatant fluid, liquid-solid separation is carried out on underflow by centrifugation, and the obtained liquid is Fe²⁺The content is 2g/L, Fe³⁺The content of the extract is 0.5g/L, Co²⁺The obtained solid is ferric oxide powder containing 61.8 percent of iron, 0.96 percent of sulfur and 0.26 percent of cobalt, the iron removal efficiency reaches 92.3 percent, and the loss rate of cobalt entering slag is 0.3 percent. FIG. 1 is an X-ray diffraction phase analysis (XRD) and scanning electron microscope (S) of a solid slag sampleEM), the main component of the solid slag sample is Fe as can be seen by XRD analysis₂O₃And SiO₂No iron vitriol, basic ferric sulfate, goethite, etc., SiO, were detected₂As one of the smelting slag-forming agents, the slag-forming agent has no influence on steel smelting. SEM analysis shows that the solid slag sample is basically composed of spherical Fe₂O₃The particle composition and the particle size distribution are uniform, which shows that the obtained solid slag sample is the ferric oxide powder with high purity and uniform particle size distribution.

Comparative example 1

The conditions used were exactly the same as in example 1, but without addition of Co (OH)₂Cobalt and iron separation promoter. After the cobalt and iron are separated, the liquid is concentrated, filter-pressed and centrifugally separated to obtain Fe²⁺The content is 8g/L, Fe³⁺The content is 1.5g/L, Co²⁺The obtained solid is a slag sample containing 48.5% of iron, 5.42% of sulfur and 0.3% of cobalt, the iron removal efficiency reaches 88.6%, the cobalt slag-in loss rate is 0.37%, and the slag contains low iron and high sulfur and can not be used as a raw material of a steel plant. FIG. 2 is an X-ray diffraction phase analysis diagram (XRD) and a scanning electron microscope diagram (SEM) of the solid slag sample, and the XRD analysis shows that the main component of the solid slag sample is Fe₂O₃And Fe (OH) SO₄Due to Fe (OH) SO₄The iron content in the phase is only 33.13%, and the sulfur content is as high as 18.93%, so that the total iron content in the slag is obviously reduced, and the sulfur content in the slag is increased. SEM analysis shows that the sample has spherical Fe₂O₃Besides the particles, the slag also contains more rods with clear edges and corners, which further proves that certain Fe (OH) SO exists in the slag sample₄A substance.

It can be seen from the comparison of example 1 and comparative example 1 that the addition of the cobalt-iron separation promoter plays a crucial role in the iron removal effect, the separation promoter is not added, the obtained solid slag sample has low iron content and high sulfur content, and cannot be used as a steel smelting raw material, so that the comprehensive utilization of iron resources is difficult to realize.

Example 2

Leaching a certain cobalt-copper-iron alloy material by sulfuric acid at 80 ℃ to obtain a cobalt-containing alloy material containing 75g/L iron and 15g/L cobaltDiluting the leachate to 1.5 times of volume by using the separated liquid of cobalt and iron to obtain diluted liquid containing 50.6g/L of iron and 21g/L of cobalt, adding Co (OH) according to the concentration of 30g/L₂The addition amount of the iron removal promoter is 11.2 g/L. To obtain a solution before iron removal with pH of 3.5. Continuously pumping the mixture into a closed high-pressure device, reacting in an oxygen partial pressure environment of 0.3MPa at 180 ℃, controlling the liquid flux speed to enable the solution to flow in the high-pressure device for about 4 hours, after the reaction is finished, releasing the pressure of the reacted solution through a pressure relief device, and returning the generated steam heat resource to the front end for maintaining the temperature of the iron removing front liquid. The liquid obtained after cobalt and iron separation after pressure relief enters a thickener at the temperature of 85 ℃, after flocculation and sedimentation, liquid-solid separation is realized by filter pressing of supernatant fluid, liquid-solid separation is carried out on underflow by centrifugation, and the obtained liquid is Fe²⁺The content is 1.8g/L, Fe³⁺The content of the mixed solution is 0.42g/L, Co²⁺The obtained solid is iron oxide concentrate powder containing 63.4 percent of iron, 0.87 percent of sulfur and 0.22 percent of cobalt, the iron removal efficiency reaches 90.5 percent, the cobalt-in-slag loss rate is 0.32 percent, and the solid slag sample is iron oxide powder with high purity and uniform particle size distribution.

Example 3

Leaching a certain cobalt-copper-iron alloy material by sulfuric acid at 80 ℃ to obtain high-concentration leachate containing 103g/L of iron and 18g/L of cobalt, diluting the leachate to 1.5 times of the volume of the leachate by using the separated liquid of cobalt and iron to obtain diluted liquid containing 70.3g/L of iron and 32.5g/L of cobalt, adding CoCO according to the concentration of 50g/L₃The addition amount of the iron removal promoter is 41.5 g/L. Thus obtaining a solution before iron removal with the pH value of 4.0. Continuously pumping the mixture into a closed high-pressure device, reacting in an oxygen partial pressure environment of 0.3MPa at 180 ℃, controlling the flux speed of the liquid, enabling the solution to flow in the high-pressure device for reaction for about 2 hours, after the reaction is finished, releasing the pressure of the separated liquid through a pressure relief device, and returning the generated steam heat resource to the front end for maintaining the temperature of the iron removing front liquid. Allowing the cobalt and iron separated solution after pressure relief to enter a thickener at 80 ℃, performing flocculation sedimentation, performing filter pressing on supernatant to realize liquid-solid separation, and performing liquid-solid separation on underflow by centrifugation to obtain Fe liquid²⁺The content is 2.34g/L, Fe³⁺The content is 0.86g/L, Co²⁺The obtained solid is iron 63.7%, sulfur 0.75%, and cobalt 0.21%The iron removal efficiency of the iron oxide concentrate powder reaches 94.5 percent, the cobalt slag loss rate is 0.26 percent, and the obtained solid slag sample is the iron oxide powder with high purity and uniform particle size distribution.

Example 4

Leaching a certain cobalt-copper-iron alloy material by sulfuric acid at 80 ℃ to obtain high-concentration leachate containing 103g/L of iron and 18g/L of cobalt, diluting the leachate to 1.5 times of the volume of the leachate by using the separated liquid of cobalt and iron to obtain diluted liquid containing 65g/L of iron and 32g/L of cobalt, adding Co (OH) according to the concentration of 50g/L₂The addition amount of the iron removal promoter is 29.9 g/L. To obtain a pH value of 4.36. Continuously pumping the mixture into a closed high-pressure device, reacting at 200 ℃ under the oxygen partial pressure environment of 0.4MPa, controlling the flux speed of the liquid to enable the solution to flow in the high-pressure device for about 4 hours, after the reaction is finished, releasing the pressure of the separated liquid through a pressure relief device, and returning the generated steam heat resource to the front end to maintain the temperature of the iron removing front liquid. Allowing the cobalt and iron separated solution after pressure relief to enter a thickener at 82 ℃, flocculating and settling, performing filter pressing on supernatant to realize liquid-solid separation, centrifuging underflow to perform liquid-solid separation, and obtaining Fe as the liquid²⁺The content is 2.1g/L, Fe³⁺The content of the additive is 0.64g/L, Co²⁺The obtained solid is iron oxide concentrate powder containing 65.4 percent of iron, 0.45 percent of sulfur and 0.15 percent of cobalt, the iron removal efficiency reaches 93.5 percent, and the loss rate of cobalt in slag is 0.24 percent. The obtained solid slag sample is ferric oxide powder with high purity and uniform particle size distribution.

Example 5

Leaching a certain cobalt-copper-iron alloy material by sulfuric acid at 80 ℃ to obtain high-concentration leachate containing 80g/L of iron and 15g/L of cobalt, diluting the leachate to 1.6 times of the volume of the leachate by using the solution after separating cobalt and iron to obtain diluted solution containing 53g/L of iron and 34g/L of cobalt, adding Co (OH) according to the concentration of 65g/L₂The addition amount of the iron removal promoter is 53.0 g/L. To obtain a solution before iron removal with pH of 5.0. Continuously pumping the mixture into a closed high-pressure device, reacting at 210 ℃ under the oxygen partial pressure environment of 0.3MPa, controlling the flux speed of the liquid to enable the solution to flow in the high-pressure device for reaction for about 4 hours, after the reaction is finished, releasing the pressure of the separated liquid through a pressure relief device, and returning the generated steam heat resource to the front end to maintain the temperature of the iron removing front liquid. Pressure filtration is utilized to cobalt iron after pressure reliefPerforming liquid-solid separation to obtain Fe liquid²⁺The content is 1.8g/L, Fe³⁺The content of the additive is 0.35g/L, Co²⁺The obtained solid is iron oxide concentrate powder containing 65.4 percent of iron, 0.72 percent of sulfur and 0.21 percent of cobalt, the iron removal efficiency reaches 95.4 percent, and the cobalt slag-in loss rate is 0.23 percent, which shows that the obtained solid slag sample is iron oxide powder with high purity and uniform particle size distribution.

Claims

1. A method for separating cobalt-doped high-pressure cobalt and iron from high-concentration cobalt and iron leachate is characterized by comprising the following steps of:

D. performing liquid-solid separation on the liquid after cobalt-iron separation by adopting the combination of concentration, filter pressing and centrifugation to obtain solid iron oxide powder, and performing SO treatment on the obtained liquid₂Returning to the front end after reduction to be used as a diluent of the high-concentration cobalt-iron leaching solution or entering an extraction system to be used as a cobalt extraction stock solution.

2. The method according to claim 1, wherein the cobalt-doped high-pressure cobalt-iron separation is carried out by using cobalt-copper-iron oxide mixture, cobalt-copper-iron hydroxide mixture or crude cobalt-copper-iron alloy material as the cobalt-copper-iron-containing raw material, atmospheric pressure reduction leaching as the sulfuric acid leaching, and Co-containing cobalt-iron leaching solution as the high-concentration cobalt-iron leaching solution²⁺And Fe²⁺In the sulfate leach liquor of (1), wherein, Co²⁺Ion concentration of 15-60 g/L, Fe²⁺The ion concentration is 50-110 g/L.

3. The method according to claim 1, wherein the dilution is a dilution of iron ion concentration, the dilution ratio is determined according to the initial iron ion concentration of the leachate, the set concentration is a concentration of iron ion after the dilution is controlled to 45-80 g/L, and the dilution is a cobalt-iron separated solution or tap water.

4. The method according to claim 1, wherein the cobalt-containing compound is CoO or Co (OH)₂、CoCO₃One or a mixture of two or more of (1).

5. The method for separating cobalt-doped high-pressure cobalt from iron as claimed in claim 4, wherein the amount of the cobalt-containing compound added is 5-60 g/L.

6. The method for separating Co-doped high-pressure Co from Fe in the leaching solution of high-concentration Co and Fe as claimed in claim 1, wherein the pH of the pre-Co-Fe-separation solution is 2-5.5, the temperature is 65-70 ℃, and Fe is²⁺The proportion of the Fe accounts for 93-98 percent of the total Fe.

7. The method according to claim 1, wherein the closed high-pressure plant comprises 3 stages connected in series, each stage being stirred individually, wherein the 1 st stage is not heated and has a temperature of 50-80 ℃, the heat is derived from the temperature of the cobalt-iron separation precursor and the relative flow of the gas in the 2 nd stage kettle, and the 2 nd and 3 rd stages are heated by steam coils and have a temperature of 160-190 ℃.

8. The method according to claim 7, wherein the high oxygen partial pressure environment is created by using pure oxygen, the oxygen partial pressure is maintained at 0.1-0.6 MPa, oxygen is introduced into the reaction solution through a high pressure pipeline at the bottom of the side wall of the closed high pressure equipment, and each stage of the closed high pressure equipment is provided with 5 oxygen inlets.

9. A process as claimed in claim 1The method for separating cobalt-doped high-pressure cobalt and iron from the high-concentration cobalt and iron leaching solution is characterized in that the cobalt and iron separated solution is subjected to pressure relief through a pressure relief device, and generated steam heat resources return to the front end to maintain the temperature of the cobalt and iron separated front liquid; allowing the cobalt and iron separated liquid subjected to pressure relief to enter a thickener at the temperature of 60-90 ℃, performing flocculation sedimentation, performing filter pressing on supernatant to realize liquid-solid separation, performing centrifugal separation on underflow to realize liquid-solid separation, and allowing the obtained liquid to pass through SO₂Reducing, and obtaining the solid which is ferric oxide powder.

10. The method for separating cobalt-doped high-pressure cobalt from iron as claimed in claim 9, wherein the iron oxide powder contains less than 1wt% of sulfur, 60-65 wt% of iron, less than 10wt% of water, and more than 90% of particles with a size of 200 meshes.