Method for leaching and extracting cobalt and copper from copper-cobalt sulfide concentrate
Patent Information
- Application Number
- AU2025210850
- Authority / Receiving Office
- AU · AU
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-03-18
- Filing Date
- 2025-04-28
- Publication Date
- 2026-10-08
Abstract
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims priority to Chinese Patent Application No. 202510318724.9, filed on March 18, 2025, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD
[0002] The present disclosure relates to the field of hydrometallurgy, and more particularly to a method for extracting cobalt and copper from a copper-cobalt sulfide concentrate. BACKGROUND
[0003] An extraction process of valuable metals such as Cu and Co in the copper-cobalt sulfide concentrate mainly includes a pyrometallurgical process, a wet acid leaching process, a wet acid leaching + ammonia extraction process, a wet acid leaching + carbonate reverse flotation process, and a wet acid leaching + oxygen pressure leaching process.
[0004] The pyrometallurgical process has been basically eliminated due to its high energy consumption, serious environmental pollution, and strong corrosion to equipment. The ammonia extraction process has also been basically eliminated due to a high price of ammonia extractant. Although the wet acid leaching + ammonia extraction process may recover Cu and Co from the copper-cobalt sulfide concentrate, the ammonia extractant is difficult to recover, a consumption of the ammonia extractant is large, and the ammonia extractant is prone to generate by-products with a foul odor in a recovery process. The wet acid leaching + carbonate reverse flotation process has a high reagent consumption for the carbonate reverse flotation and produces a large amount of medium and low-quality flotation foam in the reverse flotation process. The flotation foam may cause serious corrosion of the equipment and unstable production. The wet acid leaching + oxygen pressure leaching process has advantages of a simple operation, a short process, a low corrosion of the equipment and a high product purity. However, an oxygen pressure leaching has a low degree of oxidation of S, Fe and Al from the copper-cobalt sulfide concentrate, and an amount of leaching residue after the oxygen pressure leaching is large, a cost of leaching residue treatment is high, and the treatment is difficult, which is not conducive to a recovery of valuable metals from the copper-cobalt sulfide concentrate. SUMMARY
[0005] In order to achieve the above purpose, the present disclosure provides a method for extracting cobalt and copper from a copper-cobalt sulfide concentrate, which includes: in S1, mixing the copper-cobalt sulfide concentrate with an iron-aluminum containing slag to obtain a mixed ore having a weight ratio of the copper-cobalt sulfide concentrate to the iron-aluminum containing slag of 2.5:1 to 8:1; in S2, performing a slurry preparation by mixing the mixed ore with water to obtain a first ore slurry; in S3, pre-acid leaching the first ore slurry in an acid-to-ore ratio of 150 kg / t to 220 kg / t to obtain a second ore slurry; and in S4, performing an oxygen pressure leaching on the second ore slurry for 0.8 h to 3.0 h at an oxygen partial pressure of 0.3 MPa to 1.2 MPa and a stirring speed of 600 r / min to 900 r / min, and performing a solid-liquid separation to obtain a leachate. The iron-aluminum containing slag is a waste slag precipitated from a process of removing iron and aluminum by neutralization in a process of extracting cobalt and copper from a copper-cobalt sulfide ore.
[0006] Further, by weight, the iron-aluminum containing slag includes 0.1 to 0.5 parts of Cu, 0.1 to 0.6 parts of Co, 2.5 to 5.0 parts of Fe and 5.0 to 8.0 parts of Al.
[0007] Further, by weight, the copper-cobalt sulfide concentrate includes 15.0 to 25.0 parts of Cu, 8.0 to 15.0 parts of Co, 1.0 to 3.0 parts of Fe and 1.0 to 2.5 parts of Al.
[0008] Further, 97 to 99 wt% of the copper-cobalt sulfide concentrate has a particle size of 200 mesh; and / or 98 to 99 wt% of the iron-aluminum containing slag has a particle size of 150 mesh.
[0009] Furthermore, D50 of the copper-cobalt sulfide concentrate is 100 mesh to 150 mesh; and / or D50 of the iron-aluminum containing slag is 80 mesh to 120 mesh.
[0010] Further, the mixed ore has a weight ratio of the copper-cobalt sulfide concentrate to the iron-aluminum containing slag of 5:1 to 8:1.
[0011] Further, in the S2, a liquid-to-solid ratio for the slurry preparation is 4:1 to 12:1, and the slurry preparation is performed at a stirring speed of 300 r / min to 800 r / min.
[0012] Further, in the S3, an inorganic acid solution and / or an organic acid solution with a mass concentration of 50% to 98% is used for the pre-acid leaching.
[0013] Furthermore, in the S3, the pre-acid leaching is performed at a temperature of 25 °C to 80 °C for 60 min to 120 min.
[0014] Further, in the S4, the oxygen pressure leaching is performed at a temperature of 160 °C to 220 °C; in some embodiments, a pH value of the leachate is 1.0 to 2.5.
[0015] By applying the technical solution of the present disclosure, by mixing the copper cobalt sulfide concentrate with the iron-aluminum containing slag, not only the leaching rates of Co and Cu valuable metals from the copper-cobalt sulfide concentrate are effectively improved, but also a resource recycling of the iron-aluminum containing slag produced in a process of extracting cobalt and copper from the copper-cobalt sulfide ore is achieved, thereby reducing the environmental pollution and lowering the production costs. DETAILED DESCRIPTION
[0016] It should be noted that, in the absence of conflict, embodiments and features in embodiments of the present disclosure may be combined with each other. The present disclosure will be described in detail below with reference to embodiments.
[0017] As described in the background, there is a problem in the related art that it is impossible to improve the leaching rates of cobalt and copper from the copper-cobalt sulfide concentrate while reducing recovery rates of iron and aluminum therein. The present disclosure provides a method for extracting cobalt and copper from a copper-cobalt sulfide concentrate, which includes: in S1, mixing the copper-cobalt sulfide concentrate with an iron-aluminum containing slag to obtain a mixed ore having a weight ratio of the copper-cobalt sulfide concentrate to the iron-aluminum containing slag of 2.5:1 to 8:1; in S2, performing a slurry preparation by mixing the mixed ore with water to obtain a first ore slurry; in S3, pre-acid leaching the first ore slurry in an acid-to-ore ratio of 150 kg / t to 220 kg / t to obtain a second ore slurry; and in S4, performing an oxygen pressure leaching on the second ore slurry for 0.8 h to 3.0 h at an oxygen partial pressure of 0.3 MPa to 1.2 MPa and a stirring speed of 600 r / min to 900 r / min, and performing a solid-liquid separation to obtain a leachate. The iron-aluminum containing slag is a waste slag precipitated from a process of removing iron and aluminum by neutralization in a process of extracting cobalt and copper from a copper-cobalt sulfide ore.
[0018] The present disclosure reintroduces the iron-aluminum containing slag produced in a process of removing iron and aluminum in the process of extracting cobalt and copper from the copper-cobalt sulfide ore into the process of extracting cobalt and copper from the copper-cobalt sulfide concentrate, and uses it as an inhibitor for inhibiting a leaching of aluminum in a leaching process of the copper-cobalt sulfide concentrate, thereby achieving an efficient inhibition of a leaching of impurity elements such as iron and aluminum from the copper-cobalt sulfide concentrate, achieving an efficient leaching of valuable metals such as copper and cobalt therein, and also achieving an effective recovery of a small amount of copper and cobalt in the ironaluminum containing slag. In some embodiments, the weight ratio of the copper-cobalt sulfide concentrate to the iron-aluminum containing slag is strictly limited to 2.5:1 to 8:1, and the two are mixed according to this ratio. Within this weight ratio range, the leaching of Fe and Al may be more effectively inhibited, and Ni and Co may be efficiently recovered. At the same time, at this weight ratio, an efficiency of oxygen pressure leaching may be significantly optimized, the leaching rates of copper and cobalt may be increased, while lower iron and aluminum leaching rates may be ensured, achieving more effective Ni and Co separation and recovery. At the same time, the acid-to-ore ratio may control a pH value during a reaction and maintain it under optimal acidic conditions, thereby ensuring an efficient leaching of metals while inhibiting a leaching of other impurity elements (i.e., iron and aluminum) that are not desired to dissolve. More importantly, since the acid-to-ore ratio in the pre-acid leaching process directly affects an amount of sulfuric acid used and a generation of sulfate ions, a good balance of sulfate ions in the second ore slurry may be achieved in an acid-to-ore ratio range of 150 kg / t to 220 kg / t, avoiding a generation of too many sulfate ions to prevent an excess sulfuric acid in the solution, which in turn affects a treatment of the leachate and a recovery of Ni and Co. Finally, strictly controlling oxygen pressure leaching conditions for the above special ore slurry system is as above, which helps to provide a sufficient oxidation leaching power, so that metal sulfides in the copper-cobalt sulfide concentrate may be more efficiently oxidized, dissolved and leached, and a difficulty of oxidation of different metals in the leaching process may also be adjusted, thereby inhibiting the leaching of impurities such as iron and aluminum while increasing the leaching rates of copper and cobalt, thereby improving a purity, recovery efficiency and selectivity of the metals.
[0019] It should be particularly noted that the above steps and corresponding conditions in the leaching and recovery method provided by the present disclosure cooperate with each other as an overall technical solution, that is, forming a complete technical route of “mixing ore with a specific weight ratio ^ a slurry preparation ^ pre-acid leaching with a specific acid-to-ore ratio ^ oxygen pressure leaching with specific conditions”. In addition to the design of a process, it also includes a coordination optimization of parameters in each process stage. For the leaching of cobalt and copper from the copper-cobalt sulfide concentrate, compared with a conventional method including a pre-acid leaching + oxygen pressure leaching process commonly used in the art, it may more effectively improve the leaching rates of Ni and Co, and significantly inhibit the leaching of Fe and Al. That is, the above steps in the leaching method provided by the present disclosure, in addition to their own advantages, are more importantly able to cooperate with each other, that is, as one overall solution, to achieve an efficient and highly selective extraction of cobalt and copper from the copper-cobalt sulfide concentrate.
[0020] In general, the above method provided by the present disclosure not only has advantages of a high copper and cobalt leaching rate, a low iron and aluminum leaching rate, a good balance of sulfate ions in the leaching process, and no obvious excess sulfuric acid, but also may achieve a secondary recycling and utilization of iron-aluminum containing slag, thus having excellent environmental and economic benefits.
[0021] In several typical implementations, it is preferred to use an acid-to-ore ratio of 200 kg / t to 220 kg / t during a pre-acid leaching process in order to provide a sufficiently acidic environment, thereby more effectively promoting a dissolution of metal sulfides in the coppercobalt sulfide concentrate and significantly improving leaching rates of copper and cobalt.
[0022] As for a raw material of iron-aluminum containing slag, the inventors have preferably determined through a large number of experiments that, by weight, the iron-aluminum containing slag includes 0.1 to 0.5 parts of Cu, 0.1 to 0.6 parts of Co, 2.5 to 5.0 parts of Fe and 5.0 to 8.0 parts of Al. The iron-aluminum containing slag with this component has a high content of Fe and Al. At the same time, by coordinating conditions (such as an oxygen partial pressure, a stirring speed, a leaching time, etc.) of the above pre-acid leaching and the oxygen pressure leaching process, more Fe and Al may be retained in the leaching residue instead of leaching into the solution, that is, having a good inhibitory effect, thereby more effectively optimizing a metal content of the leachate and improving an efficiency of subsequent metal separation and recovery.
[0023] In some embodiments, the iron-aluminum containing slag with the above compositions may be obtained by subjecting a copper-cobalt ore, a copper-cobalt concentrate and other iron-aluminum-containing minerals to processes such as an acid leaching, an alkali leaching and an oxidation leaching to generate insoluble iron sulfate (Fe2(SO4)3), aluminum sulfate (Al2(SO4)3) and other substances, which remain in an oxygen pressure leaching residue in an insoluble form, thereby forming the iron-aluminum containing slag. During this process, a small amount of Fe / Al may enter the leachate, and then by neutralization and precipitation (pH of the solution being adjusted to 4.5 to 5.2), iron and aluminum ions may be precipitated into the slag, and the iron-aluminum containing slag may also be formed.
[0024] As for a main processing object, the copper-cobalt sulfide concentrate preferably, by weight, includes 15.0 to 25.0 parts of Cu, 8.0 to 15.0 parts of Co, 1.0 to 3.0 parts of Fe and 1.0 to 2.5 parts of Al in terms of, so as to better adapt to the above leaching method and achieve higher leaching rates of cobalt and copper.
[0025] Further, 97 to 99 wt% of the copper-cobalt sulfide concentrate has a particle size of 200 mesh; and / or 98 to 99 wt% of the iron-aluminum containing slag has a particle size of 150 mesh. The above preferred copper-cobalt sulfide concentrate and iron-aluminum containing slag with the particle size ranges may further increase the contact area between the two, making the mixed ore obtained by mixing ores more uniform, and also making the pre-acid leaching and the oxygen pressure leaching more sufficient, thereby increasing the leaching rates of cobalt and copper. In several typical implementations, it is preferred that D50 of the copper-cobalt sulfide concentrate is 100 mesh to 150 mesh; and / or D50 of the iron-aluminum containing slag is 80 mesh to 120 mesh, which helps to more effectively improve the uniformity of the obtained mixed ore, to improve a stability and an efficiency of the leaching process, thereby increasing the leaching rates of cobalt and copper. More importantly, the above two particle size ranges may more significantly affect a metal leaching selectivity. The copper-cobalt sulfide concentrate with a smaller particle size may increase its surface area, thereby increasing a dissolution rate, promoting a dissolution of a small amount of Cu and Co therin, and improving metal recovery rates. The ironaluminum containing slag with a larger particle size is beneficial to inhibit the leaching of Fe and Al. At the same time, the above particle size difference may promote a good contact and mixing between the copper-cobalt sulfide concentrate and the iron-aluminum containing slag, thereby improving an efficiency and rate of a metal leaching reaction.
[0026] In order to better adapt to the above particle size relationship, the inventors further optimized the weight of the two through a large number of experiments, so that the mixed ore has a weight ratio of the copper-cobalt sulfide concentrate to the iron-aluminum containing slag of 5:1 to 8:1, thereby obtaining a better extraction effect, and more effectively improving the leaching rates of Cu and Co while inhibiting the leaching of Fe and Al.
[0027] After the mixed ore is obtained, it is preferred that in the S2, a liquid-to-solid ratio for the slurry preparation is 4:1 to 12:1, and the slurry preparation is performed at a stirring speed of 300 r / min to 800 r / min. The optimization of conditions of the above slurry preparation may obtain the first ore slurry with a higher uniformity, dispersibility and fluidity, thereby promoting an improvement of an efficiency of subsequent pre-acid leaching and oxygen pressure leaching processes, and ultimately improving the leaching rates of Co and Cu.
[0028] In order to adapt to conditions of the above pre-acid leaching, achieve the pre-acid leaching and oxygen pressure leaching with a higher efficiency, and reduce an introduction of impurities, it is preferred that in the S3, an inorganic acid solution and / or an organic acid solution with a mass concentration of 50% to 98% is used for the pre-acid leaching. It is preferred that the inorganic acid solution is a sulfuric acid solution. Compared with other types of acid solutions commonly used in the art, sulfuric acid, i.e., inorganic acid solution with the above mass concentration is a strong acid, which may efficiently dissolve copper sulfide (such as CuS, Cu2S) and cobalt sulfide (such as CoS, CoS2), thereby achieving a high leaching rate. At the same time, by-products (such as sulfates) produced during a sulfuric acid leaching may be further processed and utilized to reduce waste emissions.
[0029] In several typical implementations, it is preferred that in the S3, an organic acid solution with a molar concentration of 0.1 mol / L to 0.5 mol / L is used for the pre-acid leaching, and the organic acid solution is selected from one or more of oxalic acid, citric acid and tartaric acid. Compared with sulfuric acid, a strong acid solution, the above organic acid solution has a higher selectivity, may form stable complexes with copper and cobalt, and reduce a co-leaching of impurities, thereby being able to more effectively extract copper and cobalt, which is particularly suitable for processing such low-grade, complex-composition ores as processed by the present disclosure. At the same time, the organic acid has a little impact on the environment and is environmentally friendly. Further, more preferably, a molar concentration of the organic acid used is 0.48 mol / L to 0.5 mol / L, so as to further improve the leaching rate of each element on the basis of improving the selectivity and achieve a better extraction effect.
[0030] Further, in the S3, in order to better balance a reaction efficiency in the pre-acid leaching and also allow the metal sulfide to react more fully with the acid to improve the leaching rate, it is preferred that the pre-acid leaching is performed at a temperature of 25 °C to 80 °C for 60 min to 120 min. It is preferred that the pre-acid leaching is performed at a stirring speed of 300 r / min to 700 r / min, which may promote uniform mixing of the ore slurry and accelerate a contact between reactants, thereby further improving the reaction rate and leaching efficiency. In some embodiments, responding to a pH value of the second ore slurry reaching 0.8 to 2, the S4 is performed. At this time, a pH value range of 0.8 to 2 may provide a stronger acidic environment, promote the dissolution of metal sulfides, and at the same time, inhibit a dissolution of certain impurity elements, such as Fe and Al. In some embodiments, in a case where the pH value reaches this range, a pre-acid leaching process is considered to be basically completed, and an oxygen pressure leaching step is then entered, which may promote an efficient leaching of cobalt and copper metals, while reducing the dissolution of impurities and more significantly improving the leaching rates of cobalt and copper metals.
[0031] In several typical implementations, in the S4, the oxygen pressure leaching is performed at a temperature of 160 °C to 220 °C. In this temperature range, an oxidation reaction rate may be increases, a dissolution of metal sulfides such as copper and cobalt is accelerated, and a leaching efficiency is improved. At the same time, in this temperature range, it is beneficial to a deep oxidation of metal sulfides, converting insoluble sulfides into more soluble forms, thereby more effectively improving the leaching rate of metals. In particular, this temperature may more effectively control a balance of the sulfate ions in the reaction system, optimize an amount of sulfate ions generated, maintain a chemical balance of the leachate, and facilitate a subsequent metal separation, that is, to achieve a leaching of valuable metals in the copper-cobalt sulfide concentrate with the higher selectivity. In several more typical implementations, a pH value of the leachate is 1 to 2.5. In the leachate within this acidity range, leaching rates of metals such as copper and cobalt may be optimized, while the dissolution of impurities such as Fe and Al is inhibited, ultimately achieving an improved purity of the leachate and a highly selective recovery of the metals.
[0032] The present disclosure is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present disclosure.
[0033] Unless otherwise defined, all technical terms used hereinafter have the same meanings as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present disclosure.
[0034] Example 1
[0035] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The copper-cobalt sulfide concentrate and an iron-aluminum containing slag are provided, and compositions and contents of the two are shown in Table 1. The coppercobalt sulfide concentrate is obtained by a flotation enrichment of a copper-cobalt sulfide ore, and the iron-aluminum containing slag is obtained by neutralization and precipitation of a leachate of the copper-cobalt sulfide concentrate. In the copper-cobalt sulfide concentrate processed, a coppercobalt sulfide concentrate with a particle size of less than 200 mesh accounts for 98%; and in the iron-aluminum containing slag processed, an iron-aluminum containing slag with a particle size of less than 150 mesh accounts for 99%. Further, D50 of the copper-cobalt sulfide concentrate processed is 100 mesh, and D50 of the iron-aluminum containing slag processed is 100 mesh.
[0036] Table 1 Compositions and contents of copper-cobalt sulfide concentrate and iron aluminum containing slag wt.% Cu Co Fe Al S Others (such as, SiO2) copper-cobalt sulfide concentrate 20.72 11.70 1.68 0.92 17.88 47.1 iron-aluminum containing slag 0.26 0.31 3.15 6.06 17.20 73.02
[0037] (1) 100 g of the copper-cobalt sulfide concentrate and 18 g of the iron-aluminum containing slag were mixed to obtain a mixed ore having a weight ratio of the copper-cobalt sulfide concentrate to the iron-aluminum containing slag of 5.56:1.
[0038] (2) A liquid-to-solid ratio was controlled to be 8:1, and an ore slurry preparation was performed by mixing the mixed ore with water at a stirring speed of 500 r / min to obtain a first ore slurry.
[0039] (3) A sulfuric acid solution with a mass concentration of 98% was used, an acid-to- ore ratio was controlled to be 200 kg / t, and the first ore slurry was pre-acid leached at operating conditions of an temperature of 30 °C and a stirring speed of 500 r / min for 60 min until a pH value thereof reached 0.9 to obtain a second ore slurry.
[0040] (4) An ore slurry completed the pre-acid leaching, i.e., the second ore slurry, was transferred to an oxygen pressure leaching reactor, oxygen was introduced, and an oxygen pressure leaching was performed at conditions of 200 °C, an oxygen partial pressure of 0.4 MPa, and a stirring speed of 800 r / min for 1 h. A solid-liquid separation was performed to obtain a leachate with a pH of 1.8, which contained Co, Cu, Fe and Al.
[0041] Example 2
[0042] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The copper-cobalt sulfide concentrate and the iron-aluminum containing slag used in Example 1 were used as processing raw materials.
[0043] (1) 100 g of the copper-cobalt sulfide concentrate and 34 g of the iron-aluminum containing slag were mixed to obtain a mixed ore having a weight ratio of the copper-cobalt sulfide concentrate to the iron-aluminum containing slag of 2.94:1.
[0044] (2) A liquid-to-solid ratio was controlled to be 8:1, and an ore slurry preparation was performed by mixing the mixed ore with water at a stirring speed of 300 r / min to obtain a first ore slurry.
[0045] (3) A sulfuric acid solution with a mass concentration of 98% was used, the an acid- to-ore ratio was controlled to be 200 kg / t, and the first ore slurry was pre-acid leached at operating conditions of an temperature of 30 °C and a stirring speed of 500 r / min for 60 min until a pH value thereof reached 0.9 to obtain a second ore slurry.
[0046] (4) An ore slurry completed the pre-acid leaching, i.e., the second ore slurry, was transferred to an oxygen pressure leaching reactor, oxygen was introduced, and an oxygen pressure leaching was performed at conditions of 200 °C, an oxygen partial pressure of 0.4 MPa, and a stirring speed of 800 r / min for 1 h. A solid-liquid separation as performed to obtain a leachate with a pH of 1.8, which contained Co, Cu, Fe and Al.
[0047] Example 3
[0048] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The copper-cobalt sulfide concentrate and the iron-aluminum containing slag used in Example 1 were used as processing raw materials.
[0049] (1) 100 g of the copper-cobalt sulfide concentrate and 12.5 g of the iron-aluminum containing slag were mixed to obtain a mixed ore having a weight ratio of the copper-cobalt sulfide concentrate to the iron-aluminum containing slag of 8.00:1.
[0050] (2) A liquid-to-solid ratio was controlled to be 8:1, and an ore slurry preparation was performed by mixing the mixed ore with water at a stirring speed of 800 r / min to obtain a first ore slurry.
[0051] (3) A sulfuric acid solution with a mass concentration of 98% was used, an acid-to- ore ratio was controlled to be 200 kg / t, and the first ore slurry was pre-acid leached at operating conditions of an temperature of 30 °C and a stirring speed of 500 r / min for 60 min until a pH value thereof reached 0.9 to obtain a second ore slurry.
[0052] (4) An ore slurry completed the pre-acid leaching, i.e., the second ore slurry, was transferred to an oxygen pressure leaching reactor, oxygen was introduced, and an oxygen pressure leaching was performed at conditions of 200 °C, an oxygen partial pressure of 0.4 MPa, and a stirring speed of 800 r / min for 1 h. A solid-liquid separation was performed to obtain a leachate with a pH of 1.8, which contained Co, Cu, Fe and Al.
[0053] Example 4
[0054] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that a liquid-tosolid ratio in step (2) was changed to 4:1.
[0055] Example 5 was performed as follows. The difference between this Example and Example 1 is that in step (3), an acid-to-ore ratio was changed to 150 kg / t, and a pH value of an obtained second ore slurry was changed to 2.
[0057] Example 6
[0058] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that in step (3), an acid-to-ore ratio was changed to 220 kg / t, and a pH value of an obtained second ore slurry was changed to 0.8.
[0059] Example 7
[0060] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that a time of a pre-acid leaching in step (3) was changed to 120 min.
[0061] Example 8
[0062] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that a stirring speed in step (4) was changed to 900 r / min.
[0063] Example 9
[0064] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that an oxygen partial pressure in step (4) was changed to 1.2 MPa.
[0065] Example 10
[0066] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that a time of an oxygen pressure leaching in step (4) was changed to 0.8 h.
[0067] Example 11
[0068] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that a time of an oxygen pressure leaching in step (4) was changed to 3.0 h.
[0069] Example 12 was performed as follows. The difference between this Example and Example 1 is that D50 of the copper-cobalt sulfide concentrate processed was changed to 80 mesh, and D50 of the ironaluminum containing slag processed was changed to 50 mesh.
[0071] Example 13
[0072] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that D50 of the copper-cobalt sulfide concentrate processed was changed to 200 mesh, and D50 of the ironaluminum containing slag processed was changed to 250 mesh.
[0073] Example 14
[0074] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that a stirring speed in step (2) was changed to 900 r / min.
[0075] Example 15
[0076] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that a stirring speed in step (2) was changed to 200 r / min.
[0077] Example 16
[0078] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that in step (3), a temperature of a pre-acid leaching was changed to 20 °C, a stirring speed of the pre-acid leaching was changed to 800 r / min, a time of the pre-acid leaching was changed to 140 min, and a pH value of an obtained second ore slurry was changed to 0.6.
[0079] Example 17
[0080] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that in step (3), a temperature of a pre-acid leaching was changed to 90 °C, a stirring speed of the pre-acid leaching was changed to 200 r / min, a time of the pre-acid leaching was changed to 40 min, and a pH value of an obtained second ore slurry was changed to 2.5.
[0081] Example 18 was performed as follows. The difference between this Example and Example 1 is that a temperature of an oxygen pressure leaching in step (4) was changed to 150 °C.
[0083] Example 19
[0084] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that a temperature of an oxygen pressure leaching in step (4) was changed to 250°C.
[0085] Example 20
[0086] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Example and Example 1 is that in step (3), a sulfuric acid solution used for a pre-acid leaching was replaced by oxalic acid with a molar concentration of 0.5 mol / L.
[0087] Comparative Example 1
[0088] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Comparative Example and Example 1 is that no iron-aluminum containing slag was added, but the copper-cobalt sulfide concentrate was directly used as a mixed ore and subsequent steps were performed.
[0089] Comparative Example 2
[0090] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Comparative Example and Example 1 is that in step (1), an amount of iron-aluminum containing slag was changed to 50 g, and a weight ratio of the copper-cobalt sulfide concentrate to the iron-aluminum containing slag was 2:1.
[0091] Comparative Example 3
[0092] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Comparative Example and Example 1 is that in step (1), an amount of iron-aluminum containing slag was changed to 10 g, and a weight ratio of the copper-cobalt sulfide concentrate to the iron-aluminum containing slag was 10:1.
[0093] Comparative Example 4
[0094] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Comparative Example and Example 1 is that in step (3), an acid-to-ore ratio was changed to 120 kg / t, and a pH value of an obtained second ore slurry was changed to 2.5.
[0095] Comparative Example 5
[0096] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Comparative Example and Example 1 is that a stirring speed in step (4) was changed to 400 r / min.
[0097] Comparative Example 6
[0098] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Comparative Example and Example 1 is that an oxygen partial pressure in step (4) was changed to 0.2 MPa.
[0099] Comparative Example 7
[00100] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Comparative Example and Example 1 is that an oxygen partial pressure in step (4) was changed to 1.5 MPa.
[00101] Comparative Example 8
[00102] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Comparative Example and Example 1 is that a time of an oxygen pressure leaching in step (4) was changed to 0.5 h.
[00103] Comparative Example 9
[00104] A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate was performed as follows. The difference between this Comparative Example and Example 1 is that an equal weight of aluminum sulfate was used to replace an iron-aluminum containing slag.
[00105] Leaching rates of Co, Cu, Fe and Al in leachates obtained in the Examples and Comparative Examples are shown in Table 2.
[00106] Table 2 Leaching rates of Co, Cu, Fe and Al in leachates obtained in Examples and Comparative Examples Leaching rate of valuable metal / % Co Cu Fe Al Example 1 99.54 99.76 2.28 3.24 Example 2 99.21 99.32 2.79 3.88 Example 3 99.56 99.71 2.17 3.36 Example 4 99.52 99.22 3.03 2.98 Example 5 98.00 98.01 2.28 3.24 Example 6 99.44 99.76 2.15 2.80 Example 7 99.21 99.34 2.35 3.56 Example 8 99.52 99.65 2.57 3.09 Example 9 99.75 99.87 2.34 3.56 Example 10 99.55 99.02 3.54 3.77 Example 11 99.82 99.89 2.69 3.44 Example 12 99.11 98.92 2.93 3.59 Example 13 99.01 98.72 3.05 3.98 Example 14 99.47 99.34 3.59 3.99 Example 15 97.32 97.56 1.27 2.38 Example 16 97.18 97.23 3.69 3.95 Example 17 96.52 96.71 4.79 4.23 Example 18 98.64 98.72 2.59 2.77 Example 19 99.47 99.32 4.01 4.29 Example 20 99.61 99.74 1.08 1.92 Comparative Example 1 99.21 99.21 6.58 4.51 Comparative Example 2 90.24 91.45 14.38 12.52 Comparative Example 3 90.23 91.21 13.87 12.67 Comparative Example 4 81.41 81.17 14.34 11.96 Comparative Example 5 80.21 86.65 12.47 12.58 Comparative Example 6 87.20 89.55 8.72 9.36 Comparative Example 7 99.28 91.23 2.39 11.73 Comparative Example 8 60.23 52.38 14.53 18.72 Comparative Example 9 92.21 90.27 5.27 12.79
[00107] From the above description, it can be seen that the above Examples of the present disclosure achieve an effective utilization of the iron-aluminum precipitate slag produced in a process of treating the copper-cobalt sulfide ore, introduce it into a process of leaching cobalt and copper from the copper-cobalt sulfide concentrate, and achieve higher leaching rates of cobalt and copper.
[00108] In some embodiments, the iron-aluminum containing slag produced in the neutralization precipitation process is utilized as an inhibitor for inhibiting a leaching of iron and aluminum in the process of leaching the copper-cobalt sulfide concentrate. The concentrate and the iron-aluminum containing slag with a ratio of 2.5:1 to 8:1 are used to extract valuable metals such as copper and cobalt through a pre-leaching-oxygen pressure leaching process. By controlling the particle size and ratio of the concentrate and the iron-aluminum containing slag, and controlling the acid-to-ore ratio, liquid-to-solid ratio, oxygen partial pressure, leaching temperature and other conditions of the pre-leaching and the oxygen pressure leaching, the leaching rates of copper and cobalt are increased, and the leaching rates of iron and aluminum are reduced.
[00109] Regarding Example 14 and Example 15, a reduction in stirring speed may have a certain impact on the reaction degree and the leaching rate. When the stirring speed is increased, the leaching rates of copper and cobalt increases accordingly, but the leaching rate of impurities such as Fe may also increase accordingly. Therefore, it is preferred of the present disclosure that in the step S2, the slurry preparation is performed at a stirring speed of 300 r / min to 800 r / min, so as to match compositions of the ore slurry processed and obtain a first ore slurry with a higher uniformity, dispersibility and fluidity, thereby promoting an improvement of an efficiency of subsequent pre-acid leaching and oxygen pressure leaching processes, and ultimately improving the leaching rates of Co and Cu while reducing the leaching rate of the impurity.
[00110] Further, in Comparative Example 7, as the oxygen partial pressure increases, the leaching rates of the elements increases accordingly. However, under this condition, copper may be wrapped by iron, so its leaching rate is significantly reduced and an overall effect is poor.
[00111] It should be noted that terms “first”, “second”, etc. in the description and claims of the present disclosure are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It is to be understood that the terms so used may be interchangeable where appropriate, such that implementations of the present disclosure described herein may, for example, be implemented in an order other than those described herein.
[00112] The above descriptions are only preferred embodiments of the present disclosure disclosure may be subject to various modifications and changes. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure should be included in the protection scope of the present disclosure.
Claims
1. A method for extracting cobalt and copper from a copper-cobalt sulfide concentrate, comprising:in S1, mixing the copper-cobalt sulfide concentrate with an iron-aluminum containing slag to obtain a mixed ore having a weight ratio of the copper-cobalt sulfide concentrate to the ironaluminum containing slag of 2.5:1 to 8:1;in S2, performing a slurry preparation by mixing the mixed ore with water to obtain a first ore slurry;in S3, pre-acid leaching the first ore slurry in an acid-to-ore ratio of 150 kg / t to 220 kg / t to obtain a second ore slurry; andin S4, performing an oxygen pressure leaching on the second ore slurry for 0.8 h to 3.0 h at an oxygen partial pressure of 0.3 MPa to 1.2 MPa and a stirring speed of 600 r / min to 900 r / min, and performing a solid-liquid separation to obtain a leachate;wherein the iron-aluminum containing slag is a waste slag precipitated from a process of removing iron and aluminum by neutralization in a process of extracting cobalt and copper from a copper-cobalt sulfide ore.
2. The method for extracting cobalt and copper from the copper-cobalt sulfide concentrate according to claim 1, wherein, by weight, the iron-aluminum containing slag comprises 0.1 to 0.5 parts of Cu, 0.1 to 0.6 parts of Co, 2.5 to 5.0 parts of Fe and 5.0 to 8.0 parts of Al.
3. The method for extracting cobalt and copper from the copper-cobalt sulfide concentrate according to claim 2, wherein, by weight, the copper-cobalt sulfide concentrate comprises 15.0 to 25.0 parts of Cu, 8.0 to 15.0 parts of Co, 1.0 to 3.0 parts of Fe and 1.0 to 2.5 parts of Al.
4. The method for extracting cobalt and copper from the copper-cobalt sulfide concentrate according to any one of claims 1 to 3, wherein: 97 to 99 wt% of the copper-cobalt sulfide concentrate has a particle size of less than 200 mesh; and / or98 to 99 wt% of the iron-aluminum containing slag has a particle size of less than 150 mesh.
5. The method for extracting cobalt and copper from the copper-cobalt sulfide concentrate according to any one of claims 1 to 3, wherein D50 of the copper-cobalt sulfide concentrate is 100 mesh to 150 mesh; and / or D50 of the iron-aluminum containing slag is 80 mesh to 20 mesh.
6. The method for extracting cobalt and copper from the copper-cobalt sulfide concentrate according to any one of claims 1 to 3, wherein the mixed ore has a weight ratio of the coppercobalt sulfide concentrate to the iron-aluminum containing slag of 5:1 to 8:1.
7. The method for extracting cobalt and copper from the copper-cobalt sulfide concentrateaccording to any one of claims 1 to 3, wherein in the S2, a liquid-to-solid ratio for the slurry preparation is 4:1 to 12:1, and the slurry preparation is performed at a stirring speed of 300 r / min to 800 r / min.
8. The method for extracting cobalt and copper from the copper-cobalt sulfide concentrate according to any one of claims 1 to 3, wherein in the S3, an inorganic acid solution and / or an organic acid solution with a mass concentration of 50% to 98% is used for the pre-acid leaching.
9. The method for extracting cobalt and copper from the copper-cobalt sulfide concentrate according to any one of claims 1 to 3, wherein in the S3, the pre-acid leaching is performed at a temperature of 25 °C to 80 °C for 60 min to 120 min.
10. The method for extracting cobalt and copper from the copper-cobalt sulfide concentrate according to any one of claims 1 to 3, wherein in the S4, the oxygen pressure leaching is performed at a temperature of 160 °C to 220 °C; and a pH value of the leachate is 1 to 2.5.