阅读说明：本技术 一种钴硫精矿和氢氧化钴矿的联合浸出工艺 (Combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore ) 是由 李军秀 杜长福 于 2021-08-06 设计创作，主要内容包括：本发明公开了一种钴硫精矿和氢氧化钴矿的联合浸出工艺,该工艺包括以下步骤：将将所述钴硫精矿和所述氢氧化钴矿浆化后,得浆化液；将所述浆化液,在压力为0.6MPa～1.25MPa,温度为150℃～180℃下反应,固液分离,得固相和液相；所述液相即为浸出液。本发明的工艺通过将钴硫精矿和氢氧化钴矿高压联合浸出,高价的钴被钴硫精矿还原成低价钴,高压氧化浸出过程中,将硫离子氧化为硫酸根,将亚铁离子氧化为铁离子；同时在该环境下,铁离子水解最终形成氧化铁(Fe-(2)O-(3))和氢离子,利用生成的氢离子浸出了氢氧化钴,同时还将钴硫精矿中的钴、铜和镍浸出到溶液中；简化了钴硫精矿利用的工艺且提升了浸出效率。(The invention discloses a combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore, which comprises the following steps: slurrying the cobalt-sulfur concentrate and the cobalt hydroxide ore to obtain a slurrying solution; reacting the slurry liquid under the pressure of 0.6-1.25 MPa and the temperature of 150-180 ℃, and carrying out solid-liquid separation to obtain a solid phase and a liquid phase; the liquid phase is leachate. The process of the invention jointly leaches cobalt-sulfur concentrate and cobalt hydroxide ore under high pressure, high-valence cobalt is reduced into low-valence cobalt by the cobalt-sulfur concentrate, and in the process of high-pressure oxidation leaching, sulfur ions are oxidized into sulfate radicals, and ferrous ions are oxidized into iron ions; meanwhile, under the environment, iron ions are hydrolyzed to finally form iron oxide (Fe) 2 O 3 ) And hydrogen ions, wherein the generated hydrogen ions are utilized to leach cobalt hydroxide, and cobalt, copper and nickel in the cobalt-sulfur concentrate are leached into the solution; the process of utilizing the cobalt-sulfur concentrate is simplified, and the leaching efficiency is improved.)

1. A combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore is characterized in that: the method comprises the following steps:

slurrying the cobalt-sulfur concentrate and the cobalt hydroxide ore to obtain a slurrying solution;

reacting the slurry under the pressure of 0.6 MPa-1.25 MPa and the temperature of 150-180 ℃, and carrying out solid-liquid separation to obtain the leachate.

2. The combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore according to claim 1, characterized in that: the mass ratio of the cobalt-sulfur concentrate to the cobalt hydroxide ore is 1-2: 1-2.

3. The combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore according to claim 1, characterized in that: the mass fraction of cobalt in the cobalt-sulfur concentrate is 0.01-1%.

4. The combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore according to claim 3, characterized in that: the mass fraction of cobalt in the cobalt-sulfur concentrate is 0.2-0.5%.

5. The combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore according to claim 1, characterized in that: the mass fraction of cobalt in the cobalt hydroxide ore is 25-45%.

6. The combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore according to claim 1, characterized in that: the pH value of the slurry liquid is 3.5-4.5.

7. The combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore according to claim 1, characterized in that: oxygen is required to be introduced into the reaction; preferably, the mass ratio of the oxygen to the cobalt is 2-3: 1.

8. The combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore according to claim 1, characterized in that: the mass fraction of sulfur in the cobalt-sulfur concentrate is more than or equal to 25 percent.

9. The combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore according to claim 1, characterized in that: the stirring rate of the reaction is 150 to 300 rmp.

10. The combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore according to claim 1, characterized in that: the reaction time is 3-8 h.

Technical Field

The invention relates to the technical field of metal smelting, in particular to a combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore.

Background

Cobalt is an indispensable strategic metal in high-tech industries and plays an important role in the fields of high-temperature alloy, hard alloy, magnetic materials, chemical industry, electronic industry and the like.

Therefore, the utilization rate of the existing cobalt minerals (cobalt-sulfur concentrate, cobalt hydroxide ore and the like) is further improved, and the significance exists; the process of leaching cobalt-sulfur concentrate in the related technology mainly comprises leaching after direct sulfating roasting, leaching after oxidizing roasting-chloridizing roasting and leaching after oxidizing roasting-sulfating roasting, preparing sulfuric acid from sulfur dioxide flue gas generated by roasting, and recovering metal elements such as copper, cobalt, nickel and the like from the leaching solution. The cobalt-sulfur concentrate leaching process is complex and has large matching investment; meanwhile, the yield of cobalt is low, the concentration of leached liquid is low, the number of treatment processes is large, and the investment and output efficiency is low.

In the related technology, cobalt hydroxide ore is mainly subjected to main processes such as reduction acid leaching and the like to obtain a cobalt-rich solution, but sulfur dioxide gas is generated by using sulfur dioxide and sodium metabisulfite as reducing agents, so that the field operation environment is poor, a large amount of liquid caustic soda is consumed when sulfur dioxide cannot be effectively absorbed and enters an absorption tower, a large amount of Fe needs to be added after being reduced, and the production cost is high.

Therefore, it is necessary to develop a combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore, which has a good leaching effect.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore, and the process has good leaching effect.

The invention provides a combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore, which comprises the following steps:

slurrying the cobalt-sulfur concentrate and the cobalt hydroxide ore to obtain a slurrying solution;

reacting the slurry under the pressure of 0.6-1.25 MPa and the temperature of 150-180 ℃, and carrying out solid-liquid separation to obtain the leachate.

The leaching process of the invention utilizes cobalt-sulfur concentrate and cobalt hydroxide ore to leach under high pressure, the two ores are mixed and pulped, the pulped raw materials are leached under high pressure, and the high-valence cobalt is reduced into low-valence cobalt by the cobalt-sulfur concentrate;in the high-pressure oxidation leaching process, sulfur ions are oxidized into sulfate radicals, and ferrous ions are oxidized into iron ions; meanwhile, under the environment, iron ions are hydrolyzed to finally form iron oxide (Fe)₂O₃) And hydrogen ions are utilized to leach metal elements such as cobalt, copper and nickel in the cobalt hydroxide and cobalt-sulfur concentrate.

According to some embodiments of the invention, the mass ratio of the cobalt-sulfur concentrate to the cobalt hydroxide ore is 1-2: 1-2.

The sulfur in the cobalt-sulfur concentrate is converted into sulfuric acid, the required amount of the sulfuric acid is the sum of the consumption of the intermediate product for dissolving the cobalt hydroxide and the consumption of the sulfuric acid for dissolving the cobalt-sulfur concentrate, and the two qualities are basically equivalent.

According to some embodiments of the invention, the mass fraction of cobalt in the cobalt sulphur concentrate is between 0.01% and 1%.

According to some embodiments of the invention, the mass fraction of cobalt in the cobalt sulphur concentrate is between 0.2% and 0.5%.

According to some embodiments of the invention, the mass fraction of sulphur in the cobalt sulphur concentrate is between 20% and 30%.

According to some embodiments of the invention, the mass fraction of iron in the cobalt sulphur concentrate is between 20% and 60%.

In the oxidation leaching process, sulfur ions are oxidized into sulfate radicals, and ferrous ions are oxidized into ferric iron; at the same time, the trivalent iron is hydrolyzed to generate Fe in the process₂O₃And hydrogen ions, the generated iron oxide realizes the removal of iron; the generated hydrogen ions are used for dissolving cobalt hydroxide, cobaltic hydroxide and the like, and the leaching of cobalt is realized.

According to some embodiments of the invention, the cobalt content of the cobalt hydroxide ore is 25% to 45% by weight.

According to some embodiments of the invention, the slurry has a pH of 3.5 to 4.5.

And a small amount of acid is added into the slurry to meet the requirement of reaction starting.

According to some embodiments of the invention, the reaction requires the introduction of oxygen.

According to some embodiments of the invention, the mass ratio of the total cobalt in the oxygen and the sulfur-cobalt concentrate to the cobalt hydroxide ore is 2-3: 1.

According to some embodiments of the invention, the mass fraction of sulphur in the cobalt sulphur concentrate is at least 25%.

According to some embodiments of the invention, the reaction is stirred at a rate of 150 to 300 rmp.

According to some embodiments of the invention, the reaction time is between 3h and 8 h.

The invention has at least the following beneficial effects:

the process utilizes the sulfur ions in the cobalt-sulfur concentrate, and the sulfur ions play the role of a reducing agent to reduce a small amount of high-valence cobalt in the cobalt hydroxide; in the oxidation leaching process, sulfur ions are oxidized into sulfate radicals, and ferrous ions are oxidized into ferric iron; at the same time, the trivalent iron is hydrolyzed to generate Fe in the process₂O₃And hydrogen ions, the iron oxide produced achieves the removal of iron; the generated hydrogen ions are used for dissolving cobalt hydroxide, cobaltic hydroxide and the like, and the leaching of cobalt is realized. (ii) a The recovery rate of cobalt, copper and nickel elements in the cobalt-sulfur concentrate is high, and reaches more than 95%; meanwhile, roasting and flue gas acid making which are independently utilized by the cobalt-sulfur concentrate are reduced; the cobalt-sulfur concentrate process is simplified.

The process of the invention also simplifies the leaching process of the cobalt hydroxide ore, and does not need to additionally add a reducing agent to reduce high-valence cobalt in the cobalt hydroxide ore in the leaching process; meanwhile, the method also avoids that a large amount of iron is leached out in the reduction leaching process of the cobalt hydroxide ore, and in the process, the iron element in the cobalt hydroxide ore is converted into precipitate after being leached (iron is removed by a hematite method), so that the cost of subsequent iron purification is reduced.

Drawings

FIG. 1 is a flow chart of a combined leaching process of a cobaltous sulfide concentrate and a cobaltous hydroxide ore according to an embodiment of the invention;

FIG. 2 is a flow chart of the leaching process of cobalt-sulfur concentrate of comparative example 1 according to the present invention;

FIG. 3 is a flow chart of the leaching process of cobalt hydroxide ore in comparative example 2 of the present invention.

Detailed Description

The concept and technical effects of the present invention will be clearly and completely described below in conjunction with the embodiments to fully understand the objects, features and effects of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and those skilled in the art can obtain other embodiments without inventive effort based on the embodiments of the present invention, and all embodiments are within the protection scope of the present invention.

In the description of the present invention, reference to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The chemical composition of the cobalt sulphur concentrate in the embodiment of the invention is shown in table 1.

Table 1 chemical composition of cobalt-sulfur concentrate in the embodiment of the present invention (mass%)

The chemical composition of the cobalt sulphur concentrate was graded in six grades, see table 2.

TABLE 2 chemical composition grade of S-Co concentrate

The cobalt-sulfur concentrate has low content of valuable metals, the roasting leachate has metal content of 2-5 g/L, the content is extremely low, the iron is removed from the residual liquid after copper extraction, the liquid after iron removal is enriched, and the enriched slag is subjected to acid dissolution and then subjected to normal impurity removal and extraction processes.

The chemical composition of cobalt hydroxide ore in the embodiment of the present invention is shown in table 3.

TABLE 3 chemical composition of cobalt hydroxide ore in the embodiment of the present invention

Serial number	Co	Cu	Ni	Fe	Mn	Zn	Ca	Mg	Other impurities
										Sample 1	40.42	0.39	0.730	2.710	2.08	-	0.23	2.97	Balance of
Sample 2	40.43	0.82	0.790	2.670	2.21	-	0.22	2.26	Balance of
										Sample 3	29.88	1.32	0.41	0.25	7.10	-	0.79	6.99	Balance of
Sample No. 4	39.94	0.76	0.075	0.56	2.44	0.15	-	-	Balance of
										Sample No. 5	37.35	0.33	0.06	2.31	1.76	0.12	-	-	Balance of
Sample No. 6	37.35	0.25	0.062	3.1	1.74	0.11	-	-	Balance of

The main chemical reactions involved in the embodiments of the present invention are as follows:

MS (Metal sulfide) +8Co (OH)₃+8H₂SO₄＝8CoSO₄+MSO₄+20H₂O (M is Co, Cu, Ni, Mn, Zn, etc.);

Co(OH)₂+H₂SO₄＝CoSO₄+2H₂O；

FeS+2O₂＝FeSO₄

MS+2O₂＝MSO₄(M is Co, Cu, Ni, Mn, Zn, etc.);

8FeSO₄+O₂+4H₂SO₄＝4Fe₂(SO₄)₃+4H₂O；

Fe₂(SO₄)₃+3H₂O＝Fe₂O₃↓+3H₂SO₄(iron removal reaction by hematite method).

The combined leaching process of the cobalt-sulfur concentrate and the cobalt hydroxide ore in the embodiment of the invention comprises the following steps as shown in figure 1:

slurrying the cobalt-sulfur concentrate and the cobalt hydroxide ore, leaching under high pressure, performing solid-liquid separation after leaching, and collecting a liquid phase to obtain a leaching solution.

Wherein, cobalt-sulfur concentrate: cobalt hydroxide ore: the mass ratio of water is 1-2: 5-10;

the temperature of high-pressure leaching is 150-180 ℃;

pressure of high pressure leaching: 0.6MPa to 1.25 MPa;

the oxygen consumption of the high-pressure leaching is 2 t-3 t/tCo;

stirring speed of high-pressure leaching: 150 rpm-300 rpm;

reaction time of high pressure leaching: 3 to 8 hours.

Example 1

The embodiment is a combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore, which comprises the following steps:

s1, selecting raw materials: the chemical composition of the cobalt-sulphur concentrate of this example is shown in table 4 and the chemical composition of the cobalt hydroxide ore is shown in table 5.

Table 4 chemical composition of cobalt-sulfur concentrate of this example (%)

Element(s)	Co	Fe	Ni	Cu	Mn	Zn	SiO2	S
									Content/%	0.3	48.82	0.14	0.083	0.033	0.022	4.05	30.79

Table 5 chemical composition of cobalt hydroxide ore (%)

Element(s)	Co	Fe	Ni	Cu	Mn	Zn
							Content/%	39.94	0.56	0.075	0.76	2.44	0.15

S2, slurrying raw materials:

adding the cobalt-sulfur concentrate, the cobalt hydroxide ore and water into a pulping tank according to the mass ratio of 1:1:5, stirring for 2 hours, and preparing into slurry (adding a sulfuric acid solution (with the mass concentration of 98%) to adjust the pH value to 4).

S3, high-pressure reaction:

adding the slurry into a high-pressure reaction kettle for reaction, carrying out solid-liquid separation after the reaction is finished, and collecting leachate and a solid phase; wherein the concentration of each element in the leachate is shown in Table 6, and the solid phase is returned to the step S2 for continuous slurrying;

wherein, the operating conditions of the high-pressure reaction kettle are as follows:

1. the temperature of the reaction kettle: 160 ℃;

2. operating pressure of the reaction kettle: 0.8 MPa;

3. oxygen consumption: 2.6 t/tCo;

4. stirring speed: 175 rpm;

5. reaction time: and 4 h.

Table 6 mass concentrations of each element in the leachate of this example

Element(s)	Co	Fe	Ni	Cu	Mn	Zn	pH
								Mass concentration/g/L	75.06	0.50	0.39	1.57	4.61	0.32	1.8

Combining the test data of this embodiment, it can be known that: this example uses a cobalt sulphur concentrate with a cobalt content of about 0.3% and a sulphur content of about 30.79%; cobalt-sulfur concentrate with high iron and low silicon dioxide (high iron means that the mass content of iron is 40-60 percent) and cobalt hydroxide ore are jointly leached under high pressure, sulfur ions are oxidized into sulfate radicals, and ferrous ions are oxidized into iron ions; meanwhile, under the environment, iron ions are hydrolyzed to finally form ferric oxide and hydrogen ions; the consumption requirement of the crude cobalt hydroxide on acid is met, and simultaneously, the iron element is converted into ferric oxide which exists in the leached slag in a precipitation form (meeting the requirement of iron removal operation by a hematite method); finally, the good effect of high leaching with the leaching rate of about 99 percent of cobalt and the leaching rate of about 98 percent of copper is realized, and the leaching rate is far higher than that of the traditional leaching method (the leaching rate of the cobalt is 75 percent and the leaching rate of the copper is 50 percent).

Example 2

The embodiment is a combined leaching process of cobalt-sulfur concentrate and cobalt hydroxide ore, which comprises the following steps:

s1, selecting raw materials: the chemical composition of the cobalt-sulphur concentrate of this example is shown in table 7 and the chemical composition of the cobalt hydroxide ore is shown in table 8.

Table 7 chemical composition of cobalt-sulfur concentrate (mass%)

Element(s)	Co	Fe	Ni	Cu	Mn	Zn	SiO2	S
									Content/%	0.53	23.21	0.079	1.23	0.13	0.015	24.04	28.69

Table 8 chemical composition of cobalt hydroxide ore (%)

Element(s)	Co	Fe	Ni	Cu	Mn	Zn
							Content/%	37.35	2.31	0.06	0.33	1.76	0.12

S2, slurrying raw materials:

adding the cobalt-sulfur concentrate, the cobalt hydroxide ore and water into a pulping tank according to the mass ratio of 1:1:5, stirring for 2 hours, and preparing into slurry (adding a sulfuric acid solution (with the mass concentration of 98%) to adjust the pH to 3.5).

S3, high-pressure reaction:

adding the slurry into a high-pressure reaction kettle for reaction, carrying out solid-liquid separation after the reaction is finished, and collecting leachate and a solid phase; wherein the concentrations of the elements in the leachate are shown in Table 9, and the solid phase is returned to the step S2 for further slurrying;

wherein, the operating conditions of the high-pressure reaction kettle are as follows:

1. the temperature of the reaction kettle: 170 ℃;

2. operating pressure of the reaction kettle: 1.0 MPa;

3. oxygen consumption: 2.5 t/tCo;

4. stirring speed: 175 rpm;

5. reaction time: 3.5 h.

Table 9 mass concentrations of respective elements in leachate of this example

Element(s)	Co	Fe	Ni	Cu	Mn	Zn	pH
								Mass concentration/g/L	70.65	0.35	0.26	2.87	3.52	0.25	2.3

Combining the test data of this embodiment, it can be known that: this example uses a cobalt sulphur concentrate with a cobalt content of about 0.5% and a sulphur content of about 28.69%; cobalt-sulfur concentrate with low iron and low silicon dioxide (the mass fraction of iron in low iron ore is 20-30%) and cobalt hydroxide ore are jointly leached under high pressure, sulfur ions are oxidized into sulfate radicals, and ferrous ions are oxidized into iron ions; meanwhile, under the environment, iron ions are hydrolyzed to finally form iron oxide (Fe)₂O₃) And hydrogen ions; the consumption requirement of the crude cobalt hydroxide on acid is met, and simultaneously, the iron element is converted into ferric oxide which exists in the leached slag in the form of precipitate (meeting the iron removal operation requirement of a hematite method); finally, the good effect of high leaching with the leaching rate of about 99 percent of cobalt and the leaching rate of about 98 percent of copper is realized, and the leaching rate is far higher than that of the traditional leaching method (the leaching rate of the cobalt is 77 percent and the leaching rate of the copper is 65 percent).

Comparative example 1

The comparative example is a leaching process of a conventional cobalt sulphur concentrate, comprising the steps as shown in figure 2:

s1, oxidizing and roasting the cobalt-sulfur-containing concentrate (same as the example 1) (the roasting temperature is 900 ℃, and the roasting time is 20min), and collecting sulfur dioxide and cinder;

s2, mixing the cinder and the cobalt-containing sulfur concentrate, carrying out sulfating roasting (roasting temperature is 610 ℃, and roasting time is 20min), and collecting sulfur dioxide and roasted sand;

s3, leaching the roasted product, performing solid-liquid separation to obtain a leaching solution, and extracting the leaching solution to remove copper (an extracting agent is N902, the volume ratio of the extracting agent to the leaching solution is 1.2: 1; Guangdong Wengjiang chemical reagent Co., Ltd.); liquid-liquid separation, collecting cobalt-containing solution and back extraction solution copper sulfate;

s4, adding calcium carbonate into the cobalt-containing solution to remove iron (the iron removal temperature is 55 ℃, calcium carbonate is added to adjust the pH value to 3.5), filtering, and collecting filtrate;

adding sodium carbonate into the filtrate, performing cobalt enrichment (adding sodium carbonate until the pH is 8.5 and the temperature is 55 ℃), performing solid-liquid separation, and collecting a solid phase to obtain a cobalt enrichment;

s5, carrying out acid dissolution (adding sulfuric acid till the pH is 2 and the temperature is 60 ℃) and iron removal (adding sodium carbonate to adjust the pH to be 3.5 and the temperature to be 70 ℃), filtering, and collecting filtrate;

adding P204 into the filtrate to remove impurities; after impurity removal is finished, adding P507 to extract and separate Co and Ni; obtaining nickel sulfate solution (the mass concentration is 100g/L) and cobalt chloride solution (the mass concentration is 100g/L, and the pH value is 2.5);

s6, precipitating nickel from the nickel sulfate solution (the precipitator is sodium carbonate, the addition amount is the ratio of the nickel sulfate to the sodium carbonate is 1: 1.1; the pH is 8.5, and the temperature is 55 ℃), and then obtaining crude nickel carbonate; cobalt is precipitated from cobalt chloride (pH is 8.5, temperature is 55 ℃) to obtain cobalt oxalate;

wherein, the sulfur dioxide in the step S1 and the step S2 is purified to remove acid to obtain sulfuric acid;

and step S3, obtaining cathode copper after the stripping solution copper sulfate is electrodeposited.

The yield of cobalt in this comparative example was 77% and the yield of copper was 65%.

Comparative example 2

The comparative example is a leaching method of a conventional cobalt hydroxide ore, comprising the steps as shown in fig. 3:

s1, adding slag washing water (the mass concentration of cobalt is about 15g/L, the pH value is about 1.5) and a sulfuric acid solution (the mass concentration of the sulfuric acid solution is 98%, and the addition amount is 1t/t cobalt) into cobalt hydroxide ore (same as in example 1) to obtain a slurry solution, wherein the volume ratio of the slag washing water to the cobalt hydroxide ore is 2: 1;

s2, reducing and leaching the slurry (sulfur dioxide (the dosage is 0.5t/t cobalt), adjusting the pH to about 1.8 by adding concentrated sulfuric acid (the mass fraction is 98%) at the temperature of 65 ℃, carrying out solid-liquid separation, and collecting a liquid phase to obtain a leaching solution, wherein the solid phase is leaching residues;

s3, purifying the leachate (the purifying agent is water, the purification temperature is 70 ℃), performing solid-liquid separation, and collecting a liquid phase to obtain a purified liquid (the pH is 3.5), wherein the solid phase is purified slag;

s4, adding P204 (di (2-ethylhexyl) phosphate, CAS number: 298-07-7) into the purified liquid to extract and remove impurities (controlling saponification rate at 65% and temperature at 25 ℃), and separating liquid from liquid to obtain impurity-removed residual liquid and impurity-removed manganese liquid;

s5, adding P507 (2-ethylhexyl phosphate, Mongolian Fine materials, Ltd.) into the remaining solution (controlling the saponification rate at 65% and the temperature at 25 ℃), and separating liquid from liquid to obtain a cobalt solution and a remaining solution after cobalt removal.

Wherein, the slag washing water in the step S1 is derived from the washing liquid (sulfuric acid solution with 1mol/L detergent) for reducing the leaching slag and the washing liquid (sulfuric acid solution with 1mol/L detergent) for purifying the slag.

In this comparative example, the cobalt recovery rate was 98% and the copper recovery rate was 98%.

Although the comparative example 2 also achieves higher cobalt recovery rate and copper recovery rate, the comparative example 2 needs to add a large amount of reducing agent and concentrated sulfuric acid in the leaching process, so that the cost is high; meanwhile, an extracting agent is selected for extraction and impurity removal, and the process operation is complicated.

The parameters disclosed in the embodiments of the present invention are all conventional in the art.

In conclusion, the process utilizes the sulfur ions in the cobalt-sulfur concentrate, and the sulfur ions play the role of a reducing agent to reduce a small amount of high-valence cobalt in the cobalt hydroxide; in the high-pressure oxidation leaching process, sulfur ions are oxidized into sulfate radicals, and ferrous ions are oxidized into iron ions; meanwhile, under the environment, iron ions are hydrolyzed to finally form iron oxide (Fe)₂O₃) And hydrogen ions, wherein the generated hydrogen ions dissolve cobalt hydroxide to produce a cobalt solution; cobalt in the cobalt-sulfur concentrate of the processThe recovery rate of copper and nickel elements is high, and the recovery rate reaches over 95 percent; meanwhile, roasting and flue gas acid making which are independently utilized by the cobalt-sulfur concentrate are reduced; simplifying the cobalt-sulfur concentrate process.

The process of the invention also simplifies the leaching process of the cobalt hydroxide ore, and does not need to additionally add a reducing agent to reduce high-valence cobalt in the cobalt hydroxide ore in the leaching process; meanwhile, the method also avoids that a large amount of iron is leached out in the reduction leaching process of the cobalt hydroxide ore, and in the process, the iron element in the cobalt hydroxide ore is converted into precipitate after being leached (iron is removed by a hematite method), so that the cost of subsequent iron purification is reduced.

The embodiments of the present invention have been described in detail with reference to the description and the drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention. Furthermore, the embodiments of the present invention and the features in the embodiments may be combined with each other without conflict.