Method for recycling battery-grade nickel and cobalt in short process from lateritic nickel ore

Abstract

A method for recycling battery-grade nickel and cobalt in a short process from lateritic nickel ore, comprising the following steps: (1) iron removal pretreatment: adding an iron removal agent into a lateritic nickel ore high pressure leachate to obtain a lateritic nickel ore feed liquid; (2) nickel-cobalt adsorption: using a resin adsorption technology to adsorb nickel and cobalt in the lateritic nickel ore feed liquid, and then carrying out desorption to obtain a preliminarily-enriched crude nickel-cobalt solution; (3) nickel-cobalt co-extraction: carrying out co-extraction treatment on the crude nickel-cobalt solution to obtain a nickel-cobalt enriched liquid containing copper impurities; and (4) copper adsorption: adsorbing and removing copper in the nickel-cobalt enriched liquid to obtain battery-grade nickel and cobalt. The technological process is short; the procedures of MHP precipitation, acid dissolution, etc. are removed; the consumption of a large amount of reagents and the energy consumption are saved; the production costs of nickel and cobalt recycling are reduced; the purity of nickel-cobalt products is improved; and the problems that in the extraction stages of existing technologies, extracting agents are prone to being poisoned, reverse extraction is difficult, and the amount of water is large are solved.

Description

A method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process Technical Field

[0001] The present invention relates to the technical field of hydrometallurgy, and in particular to a method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process. Background Art

[0002] Driven by the demand for long-range driving of new energy vehicles, ternary NCM / NCA lithium batteries (nickel cobalt manganese oxide batteries / nickel cobalt aluminum oxide batteries) will show a trend of gradually surpassing the market share of lithium iron phosphate. In order to ensure the supply of nickel and cobalt resources in the new energy industry, laterite nickel ore has become an important direction of mining in countries around the world. The Ni grade in laterite nickel ore is low (content <3%), the cobalt content is very low, and it is rich in a variety of impurity elements such as Fe, Al, Ca, Cu, Mn, Sc, Cr, Zn and Si. However, the purity of the nickel and cobalt raw materials directly affects the concentration of metal impurities such as Fe, Cu, and Zn in the prepared NCM / NCA positive electrode materials, which in turn determines the safety and cycle life of the battery.

[0003] Hydrometallurgical techniques for purifying nickel and cobalt include precipitation, extraction, and resin methods. Precipitation is simple to operate, but it results in relatively significant nickel and cobalt losses during impurity removal, making it generally used for initial nickel and cobalt enrichment and impurity removal. Both extraction and resin methods offer relatively high nickel and cobalt recovery rates. Extraction offers greater selectivity for nickel and cobalt, and is therefore generally used to obtain high-purity products. However, the extraction process is particularly cumbersome. Resin adsorption is suitable for treating solutions with lower nickel and cobalt concentrations. Currently, battery-grade nickel and cobalt are produced from laterite nickel ore leachate using a sequential process: high-pressure leaching - two-stage neutralization and iron and aluminum removal - two-stage precipitation of MHP (nickel cobalt hydroxide) - acid dissolution - impurity extraction with P204 - cobalt extraction with P507 - magnesium removal with P507 - and nickel and cobalt enrichment with P507. This process is lengthy, requires a large amount of auxiliary materials, and requires a large amount of liquid caustic soda during MHP precipitation, resulting in high nickel and cobalt losses and high overall recovery costs. To this end, some researchers have proposed that after high-pressure leaching of laterite nickel ore, impurities such as Fe, Al, Sc, Cr, and Cu can be directly removed through a P204 extraction process, and then nickel and cobalt can be co-extracted through some carboxylic acids and co-extraction system extractants, and finally the ternary NCM / NCA precursor can be prepared by blending the ingredients. Obviously, the amount of water used in the entire extraction stage of this process is very large, and the production efficiency of nickel and cobalt will drop by dozens of times, making it impossible to industrialize. It is worth noting that in the above two processes, Cr easily poisons the extractant in the extraction stage, and the Fe loaded in the organic phase needs to be stripped with hydrochloric acid. Even if Sc is stripped with alkali, the effect is not ideal.

[0004] Summary of the Invention

[0005] The purpose of the present invention is to overcome the above-mentioned technical deficiencies and provide a method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process, thereby solving the technical problems in the prior art of the extractant being easily poisoned, the difficulty of stripping, and the large amount of water required for the overall purification of nickel and cobalt.

[0006] To achieve the above technical objectives, the technical solution of the present invention provides a method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process, comprising the following steps:

[0007] (1) Iron removal pretreatment: adding an iron removal agent to the high-pressure leaching solution of laterite nickel ore to reduce the iron concentration in the high-pressure leaching solution to below 0.2 g / L to obtain a laterite nickel ore feed solution;

[0008] (2) Nickel-cobalt adsorption: nickel and cobalt in the laterite nickel ore solution are adsorbed by resin adsorption process, and then desorbed to obtain a crude nickel-cobalt solution that is initially enriched;

[0009] (3) Nickel-cobalt co-extraction: The crude nickel-cobalt solution is co-extracted to obtain a nickel-cobalt enriched solution containing copper impurities;

[0010] (4) Copper adsorption: The copper in the nickel-cobalt enriched solution is removed by adsorption to obtain battery-grade nickel-cobalt.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] The process flow of the present invention is short and eliminates the steps of MHP precipitation and acid dissolution in the current conventional laterite nickel ore hydrometallurgical process, thereby saving a large amount of reagent consumption and energy consumption, reducing the production cost of nickel and cobalt recovery, and improving the purity of the nickel and cobalt products. It also solves the problems of easy poisoning of the extractant, difficulty in stripping, and large water consumption in the extraction stage of the existing process, which is of great significance for improving the market competitiveness of NCM / NCA batteries and their new energy vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG1 is a process flow chart of a method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to the present invention. DETAILED DESCRIPTION

[0014] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0015] This invention develops a low-cost, short-process method for extracting battery-grade nickel and cobalt from laterite nickel ore. The process first reduces the iron concentration in the high-pressure leachate from the laterite nickel ore. The nickel and cobalt are then purified using a series of ion exchange resin devices to produce a leachate containing a small amount of other impurities and a pre-enriched nickel and cobalt solution. The nickel and cobalt are then enriched through a nickel-cobalt co-extraction process. Finally, the copper impurity in the nickel-cobalt sulfate solution, enriched to the target concentration, is removed using an ion exchange resin again to produce high-purity, battery-grade nickel and cobalt sulfate.

[0016] Referring to FIG1 , the present invention includes the following steps:

[0017] Step (1) iron removal pretreatment: After high-pressure leaching of the laterite nickel ore, the iron concentration in the high-pressure leaching solution of the laterite nickel ore is reduced to below 0.2 g / L, and the pH of the leaching solution is adjusted to 3-5 to obtain a laterite nickel ore feed solution.

[0018] Among them, the high-pressure leaching process of laterite nickel ore is a conventional process and is not specifically limited here.

[0019] Preferably, the raw materials for iron removal and pH adjustment include but are not limited to one or more of calcium oxide, calcium hydroxide, nickel carbonate, cobalt carbonate, etc., and those skilled in the art can select according to the situation, as long as they can remove iron and adjust the pH without introducing new impurity ions.

[0020] Step (2) nickel-cobalt adsorption: the nickel and cobalt in the laterite nickel ore solution are adsorbed by a resin adsorption process, and then desorbed with 10-20% sulfuric acid to obtain a solution of preliminarily enriched nickel-cobalt sulfate and a small amount of other impurities.

[0021] Preferably, a 1-6-stage series resin column device is used in step (2); preferably, the resin type includes but is not limited to cation exchange resin HP4020 or LSC-495.

[0022] Preferably, the resin adsorption process in step (2) specifically includes:

[0023] ① Resin activation: The resin needs to be activated with an activator before adsorption;

[0024] Further preferred activation method: the activator is activated by flowing through the column at a flow rate of 1 to 3 BV / h for 0.2 to 2 hours. Activation can also be performed by soaking the resin. After the resin is activated, the activator in the resin is rinsed with pure water so that the pH of the washing liquid discharged from the resin column is close to that of pure water.

[0025] More preferably, the activator is any one of sodium hydroxide, lithium hydroxide, magnesium hydroxide, calcium hydroxide, or a combination of at least two thereof, and the concentration of the activator is controlled to be 1 to 10%;

[0026] ②Nickel-cobalt adsorption: The laterite nickel ore liquid after iron removal is passed through the column at 2-10BV / h for adsorption. When the nickel-cobalt concentration in the resin column adsorption tail liquid is greater than 3mg / L, the feeding liquid is stopped.

[0027] ③ Resin washing: Use the crude nickel-cobalt solution after the previous resin adsorption and desorption to wash some of the impurities adsorbed on the resin at 3-15BV / h until the nickel-cobalt concentration in the tail liquid discharged from the resin column is consistent with that in the crude nickel-cobalt solution, so as to reduce the concentration of impurity elements in the final nickel-cobalt enriched solution;

[0028] ④ Resin desorption: Use 5-20% mass concentration of sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, acetic acid, etc. at a flow rate of 1-5BV / h to desorb the resin to obtain a preliminary enriched crude nickel and cobalt solution. Stop desorption when the resin safely returns to its pre-adsorption color;

[0029] ⑤Resin regeneration: Activate with activator.

[0030] Step (3) nickel-cobalt co-extraction: the crude nickel-cobalt solution obtained in step (2) is subjected to co-extraction treatment to enrich nickel and cobalt to a target concentration to obtain a nickel-cobalt enriched solution.

[0031] Preferably, the co-extraction agent is any one of the extraction systems such as HBL110, HBL116, Versatic10, DY319, etc., or a combination of at least two in any proportion.

[0032] Preferably, the co-extraction process specifically includes:

[0033] ① Prepare the extraction organic phase: mix the extractant and the diluent, and then saponify with a saponifier, controlling the dilution rate of the extractant to 10-60% and the saponification rate to 20-70%. The diluent can be kerosene No. 260 solvent oil or Escaid 110 solvent oil, etc., and the saponification level is 1-2.

[0034] More preferably, the saponifying agent is any one of sodium hydroxide, nickel hydroxide (sodium hydroxide + nickel sulfate mother liquor converted to soap) and ammonia water, or a combination of at least two of them.

[0035] ② Nickel-cobalt co-extraction: The extracted organic phase is mixed with the crude nickel-cobalt solution enriched with the resin to obtain a first loaded organic phase loaded with nickel-cobalt and a small amount of impurities and a raffinate. The volume ratio of the extracted organic phase to the crude nickel-cobalt solution is controlled to be 1:0.2-1, and the number of extraction stages is 2-12.

[0036] ③ Impurity washing: Impurities in the first loaded organic phase are washed with a washing liquid to obtain a second loaded organic phase and washing liquid containing only nickel, cobalt, and copper impurities. The volume ratio of the first loaded organic phase to the washing liquid is controlled to be 1:0.1-1. The hydrogen ion concentration in the washing liquid is low, ranging from 0.05 to 1M, to avoid nickel and cobalt loss. The number of washing stages is 1 to 8. Simultaneously, the washing liquid is incorporated into the crude nickel and cobalt solution from the extraction stage to further recover the nickel and cobalt in the washing liquid.

[0037] Further preferably, the washing liquid is sulfuric acid solution, hydrochloric acid solution, nitric acid, phosphoric acid, acetic acid solution or citric acid solution; the specific type of the washing liquid is selected according to the target product, and is preferably the same as the stripping liquid.

[0038] ④ Nickel-cobalt stripping: nickel, cobalt and copper in the second loaded organic phase are stripped with stripping liquid to obtain nickel-cobalt enriched liquid and organic phase (the organic phase can be saponified and then used as the extraction organic phase for nickel-cobalt co-extraction). The nickel-cobalt enriched liquid is a solution product of purified and enriched nickel-cobalt solution and a small amount of copper impurities; the volume ratio of the second loaded organic phase to the stripping liquid is controlled to be 1:0.05-1, the hydrogen ion concentration in the stripping liquid is 1-4.5M, and the stripping stage is 1-8.

[0039] More preferably, the stripping solution is a sulfuric acid solution, hydrochloric acid solution, nitric acid, phosphoric acid, acetic acid, or citric acid solution. The specific type is selected based on the target product. If the target product is nickel cobalt phosphate, a phosphoric acid solution is used as the stripping solution; if nickel cobalt sulfate is desired, a sulfuric acid solution is used as the stripping solution. The following examples are given using common nickel cobalt sulfate as the target product for the purpose of more clearly describing the present invention and are not intended to limit the present invention.

[0040] Step (4) copper adsorption: using a resin adsorption process to remove copper impurities in the nickel-cobalt enriched solution obtained in step (3).

[0041] The nickel-cobalt enriched solution obtained from the stripping in step (3) is passed through a single copper removal resin column at a flow rate of 3 to 15 BV / h until the copper ion concentration in the adsorption tail liquid is less than 0.3 mg / L.

[0042] Preferably, the copper removal resin is cation exchange resin KF320 or HP606.

[0043] Preferably, the copper adsorption in step (4) also includes a desorption process, and the desorption liquid is a sulfuric acid solution, hydrochloric acid solution, nitric acid, phosphoric acid or acetic acid solution with a mass concentration of 5 to 15%. During the desorption process, the flow rate of the desorption liquid is 1 to 4 BV / h. After the resin is desorbed, it does not need to undergo any treatment and directly enters the next round of copper adsorption process, forming an adsorption and copper removal cycle.

[0044] The main mechanism of action and advantages of the present invention:

[0045] (1) The process of the present invention uses a resin method to increase the nickel and cobalt concentration in the laterite nickel ore leachate to 20-30 g / L before the co-extraction of nickel and cobalt. This not only effectively reduces the amount of water in the co-extraction stage, but also reduces the impurity concentration in the leachate, thereby saving the amount of extractant and acid and alkali used in the co-extraction stage, and solving the problems of extractant poisoning and difficulty in stripping. After the nickel and cobalt are co-extracted and enriched to the target concentration, the resin method is used to remove copper, which greatly reduces the amount of water used in copper removal and improves the purity of the nickel and cobalt products.

[0046] (2) The process flow of the present invention is short and eliminates the steps of MHP precipitation and acid dissolution in the current conventional laterite nickel ore hydrometallurgical process, thereby saving a large amount of reagent consumption and energy consumption, reducing the production cost of nickel and cobalt recovery, and improving the purity of nickel and cobalt products. It also solves the problems of easy poisoning of the extractant, difficulty in stripping, and large amount of water in the extraction stage, which is of great significance for improving the market competitiveness of NCM / NCA batteries and their new energy vehicles.

[0047] (3) The process of the present invention can treat various acidic or even neutral liquids such as sulfuric acid, hydrochloric acid, nitric acid, oxalic acid, etc. containing nickel or cobalt and other impurities such as laterite nickel ore liquid and battery materials, and ultimately obtain various products such as sulfates, chlorides, carbonates, acetates, oxalates, etc. of nickel or cobalt and mixed nickel and cobalt; the present invention is suitable for but not limited to the process of extracting nickel and cobalt from acid leaching liquids of laterite nickel ore or other lithium / sodium batteries, minerals, intermediate products and wastes containing nickel / cobalt.

[0048] The present invention will be further described below through specific examples.

[0049] To avoid redundancy, some of the repeated conditions in the various embodiments of the present invention are described here: (1) the resin column adopts a three-stage series resin column device, the nickel-cobalt adsorption resin adopts HP4020; the copper removal resin adopts KF320; (2) the composition of the laterite nickel ore high-pressure leaching solution is specifically shown in Table 1.

[0050] Table 1 Composition of the laterite nickel ore high pressure leaching solution used in various embodiments of the present invention

[0051] Example 1

[0052] (1) Iron removal pretreatment: The pH of the laterite nickel ore high-pressure leaching solution was adjusted to 3.5 with CaO to complete the iron removal and obtain the laterite nickel ore feed solution, the composition of which is as follows.

[0053] Table 2 Composition of laterite nickel ore liquid after iron removal pretreatment

[0054] (2) Nickel-cobalt adsorption:

[0055] The resin was activated by soaking it in 3% sodium hydroxide for 1 hour, and then washed with pure water until the pH of the washing water was 7.

[0056] After pre-iron removal, the laterite nickel ore liquid was passed through the column at 3 BV / h for adsorption, and finally desorbed by the resin with 15% sulfuric acid at 2 BV / h to obtain a preliminary enriched crude nickel-cobalt solution, the composition of which is shown in Table 3 below. Part of this solution was used to wash the resin at a flow rate of 8 BV / h.

[0057] After desorption, the resin is treated with pure water and liquid alkali to regenerate and activate it, and enter the next round of nickel-cobalt adsorption.

[0058] Table 3 Composition of crude nickel-cobalt solution in Example 1

[0059] As shown in Table 3, the nickel and cobalt concentrations in the crude nickel-cobalt solution are 6.7 times and 4.2 times, respectively, higher than those before the resin adsorption treatment in Table 2. Therefore, during the subsequent nickel-cobalt co-extraction stage, the amount of water entering the continuous extraction tank also decreases exponentially. Furthermore, a comparison reveals that after the nickel-cobalt adsorption process, the ratios of the impurity concentrations of Mn, Mg, Ca, and Cr relative to the nickel concentration in the crude nickel-cobalt solution, particularly after the adsorption process, are 30, 53.7, 188.7, and 31.1 times higher than those before the adsorption process. This significantly reduces the consumption of extractant and acid and alkali during the co-extraction process, resolving the issue of the extractant being easily poisoned by a certain amount of Cr.

[0060] (3) Nickel-cobalt co-extraction:

[0061] The organic phase of the extraction was prepared with a dilution rate of 40% and a saponification rate of 50%. HBL110 extractant was used. The diluent was kerosene. The saponifier was 30% industrial liquid alkali (sodium hydroxide). The saponification level was 1.

[0062] The extracted organic phase was mixed with the crude nickel-cobalt solution in a volume ratio of 5:1, and the extraction stage was 4 to obtain a first loaded organic phase.

[0063] Then, 0.3 M sulfuric acid solution was used to elute impurities such as Fe, Al, Mn, Ca, Mg, Zn and Cr in the first loaded organic phase at a volume ratio of 1:0.2 to the sulfuric acid solution. The washing stage was 5 to obtain a second loaded organic phase containing only nickel, cobalt and copper impurities.

[0064] The metals in the washed second loaded organic phase were stripped clean using 1.5 M sulfuric acid. The volume ratio of the second loaded organic phase to sulfuric acid was controlled to be 3:1, and the stripping stage was 6 to obtain a nickel-cobalt enriched solution (a solution in which nickel, cobalt and a small amount of copper were further enriched). The composition is shown in Table 4 below.

[0065] Table 4 Composition of nickel-cobalt enriched solution of Example 1

[0066] As shown in Table 4, the present invention completes nickel and cobalt enrichment through a two-step enrichment process, and except for a small amount of copper impurities, the remaining components are basically removed.

[0067] (4) Copper adsorption: Finally, the nickel-cobalt enriched solution is passed through a single resin column at a flow rate of 4BV / h to remove copper from the solution, obtaining a battery-grade nickel-cobalt sulfate solution. The components are then proportioned and the solution is configured to synthesize nickel-cobalt-based binary and multi-element lithium battery positive electrode material precursors.

[0068] Example 2

[0069] The only difference from Example 1 is that the dilution rate and saponification rate of the HBL110 extractant in step (3) are increased to 50% and 60%, respectively. Since the utilization rate of the same volume of organic phase is improved, the volume ratio of the extracted organic phase and the crude nickel-cobalt solution is adaptively adjusted to 3.5:1 during extraction. Other conditions remain unchanged. The composition of the nickel-cobalt enriched solution further enriched with nickel, cobalt, and a small amount of copper is shown in Table 5 below.

[0070] Table 5 Composition of nickel-cobalt enriched solution of Example 2

[0071] From the comparison of Table 4 and Table 5, it can be seen that appropriately increasing the dilution rate and saponification rate of HBL110 extractant is beneficial to nickel and cobalt enrichment.

[0072] Example 3

[0073] (1) Iron removal pretreatment: The pH of the laterite nickel ore high-pressure leaching solution was raised to 5 using CaO. The composition of the leaching solution is shown in Table 6 below.

[0074] Table 6 Composition of laterite nickel ore liquid after iron removal pretreatment in Example 3

[0075] From the comparison of Table 2 and Table 6, it can be seen that the concentrations of impurity metal ions such as Fe, Cr, Al and Zn in the laterite nickel ore feed solution are significantly reduced; this indicates that as the amount of CaO increases, the pH value of the resulting laterite nickel ore feed solution tends to increase, which is beneficial to the removal of impurity metal ions such as Mn, Mg, Fe, Al, Cr, Zn and Cu. At the same time, in order to avoid excessive loss of nickel and cobalt, the present invention preferably controls the pH of the laterite nickel ore feed solution to be between 3 and 5.

[0076] (2) Nickel-cobalt adsorption:

[0077] Soak the resin in 5% sodium hydroxide for 0.5 h for activation, then rinse the resin with pure water until the pH of the washing water is about 7.

[0078] After iron removal, the laterite nickel ore liquid was passed through the column at 3 BV / h for adsorption, and finally desorbed by the resin with 15% sulfuric acid at 2 BV / h to obtain a preliminary enriched crude nickel-cobalt solution, the composition of which is shown in Table 7 below. Part of this solution was used to wash the resin at a flow rate of 10 BV / h.

[0079] After desorption, the resin is treated with pure water and liquid alkali to enter the next round of nickel-cobalt adsorption.

[0080] Table 7 Composition of crude nickel-cobalt solution in Example 3

[0081] From the comparison of Table 3 and Table 7, it can be seen that the effective adsorption capacity of the resin for nickel and cobalt increases due to the decrease in the impurity content in the laterite nickel ore liquid after iron removal.

[0082] (3) Nickel-cobalt co-extraction:

[0083] Prepare an extraction organic phase with a dilution rate of 50% and a saponification rate of 50%, use HBL110 extraction agent, kerosene as diluent, 30% industrial liquid alkali (sodium hydroxide) as saponifier, and the saponification level is 1.

[0084] The extracted organic phase was mixed with the crude nickel-cobalt solution at a volume ratio of 4.1:1, and the extraction stage was 3 to obtain a first loaded organic phase.

[0085] Then, 0.2 M sulfuric acid solution was used to elute impurities such as Mn, Mg, Al, Zn, Ca and Cr in the first loaded organic phase at a volume ratio of the first loaded organic phase to the sulfuric acid solution of 1:0.2. The washing stage was 4, and a second loaded organic phase containing only nickel, cobalt and copper impurities was obtained.

[0086] The metals in the washed second loaded organic phase were stripped clean using 1.5 M sulfuric acid. The volume ratio of the second loaded organic phase to sulfuric acid was controlled to 3:1, and the stripping stage was 6 to obtain a nickel-cobalt enriched solution (a solution in which nickel, cobalt and a small amount of copper were further enriched). The composition is shown in Table 8 below.

[0087] Table 8 Composition of nickel-cobalt enriched solution of Example 3

[0088] Comparison of Table 4 and Table 8 shows that the present invention can achieve a Ni content of 67.9-79.2 g / L and a Co content of 3.75-3.95 g / L in the nickel-cobalt enriched solution by combining iron removal pretreatment with two-step nickel-cobalt enrichment.

[0089] (4) Copper adsorption: Finally, the solution is passed through a single resin column at a flow rate of 5BV / h to remove copper from the solution to obtain a battery-grade nickel cobalt sulfate solution. The components are then proportioned and the solution is configured to synthesize nickel cobalt-based binary and multi-element lithium battery positive electrode material precursors.

[0090] Comparative Example 1

[0091] The difference from Example 1 is that the nickel-cobalt adsorption in step (2) is placed after the nickel-cobalt co-extraction process in step (3), and the copper adsorption in step (4) is placed before the nickel-cobalt adsorption process in step (2) or the nickel-cobalt co-extraction process in step (3). The other steps and processes are the same as those in Example 1.

[0092] The results showed that placing the nickel-cobalt adsorption in step (2) after the nickel-cobalt co-extraction process in step (3) resulted in an increase of 5.7 times in the amount of water in the feed liquid entering the continuous extraction tank during nickel-cobalt co-extraction compared to placing the nickel-cobalt adsorption before the nickel-cobalt co-extraction process. Furthermore, the ratios of the impurity concentrations of Mn, Mg, Ca, and Cr in the feed liquid relative to the nickel concentration increased by 29, 52.7, 187.7, and 30.1 times, respectively. This significantly increased the consumption of the extractant and acid, making the extractant more susceptible to Cr poisoning. Furthermore, placing the copper adsorption process before the nickel-cobalt adsorption process and the nickel-cobalt co-extraction process, respectively, increased the amount of water in the feed liquid during resin copper removal by approximately 17.3 and 1.7 times, respectively, compared to placing the copper adsorption process after the nickel-cobalt co-extraction process. This significantly affected the production efficiency of the final nickel-cobalt product.

[0093] The specific embodiments of the present invention described above do not limit the scope of protection of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process, characterized in that: The following steps are involved: (1) iron removal pretreatment: adding an iron removal agent to the high-pressure leaching solution of laterite nickel ore to reduce the iron concentration to below 0.2 g / L to obtain a laterite nickel ore feed solution; (2) Nickel-cobalt adsorption: The nickel and cobalt in the laterite nickel ore solution are adsorbed by a resin adsorption process, and then desorbed to obtain a crude nickel-cobalt solution that is initially enriched; (3) Nickel-cobalt co-extraction: co-extracting the crude nickel-cobalt solution to obtain a nickel-cobalt enriched solution containing copper impurities; (4) Copper adsorption: The copper in the nickel-cobalt enriched solution is adsorbed and removed to obtain battery-grade nickel-cobalt.

2. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 1, characterized in that: In step (1), the iron remover includes one or more of calcium oxide, calcium hydroxide, nickel carbonate and cobalt carbonate.

3. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 1 or 2, characterized in that: In step (1), the iron remover also plays a role in pH regulation, controlling the pH value of the laterite nickel ore solution to be between 3 and 5.

4. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 1, characterized in that: In step (2), the resin adsorption process specifically includes: Resin activation: Use activator to activate the resin; Nickel-cobalt adsorption: The laterite nickel ore liquid is adsorbed on the activated resin column; Resin desorption: The resin adsorbed with nickel and cobalt is desorbed with a desorption liquid to obtain a crude nickel-cobalt solution that is initially enriched.

5. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 1 or 4, characterized in that: In step (2), 1 to 6 stages of resin columns are connected in series to carry out nickel-cobalt adsorption, and the resin types include cation exchange resin HP4020 or LSC-495.

6. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 4, characterized in that: The resin activation is specifically to activate the activator through the column at a flow rate of 1 to 3 BV / h, or to directly immerse the resin for activation, and the activation time is 0.2 to 2 hours; after the activation is completed, the resin is rinsed with pure water until it is neutral.

7. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 4 or 6, characterized in that: The activator is any one of sodium hydroxide, lithium hydroxide, magnesium hydroxide and calcium hydroxide, or a combination of at least two of them; the concentration of the activator is 1-10%.

8. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 4, characterized in that: In the nickel-cobalt adsorption, the laterite nickel ore liquid is passed through the column at 2-10 BV / h for adsorption.

9. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 4, characterized in that: The desorption liquid is a sulfuric acid solution, a hydrochloric acid solution, a nitric acid solution, a phosphoric acid solution or an acetic acid solution with a mass concentration of 5 to 20%. During the desorption process, the flow rate of the desorption liquid is 1 to 5 BV / h.

10. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 4, 6, 8 or 9, characterized in that: The resin adsorption process further comprises resin washing: washing the resin obtained in the nickel-cobalt adsorption step with a crude nickel-cobalt solution at a flow rate of 3-15 BV / h, and then desorbing the resin after the washing is completed.

11. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 4, 6, 8 or 9, characterized in that: The resin adsorption process includes resin regeneration: activation with an activator.

12. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 1, characterized in that: In step (3), the co-extraction process specifically includes: Using an extraction organic phase to co-extract nickel and cobalt from a crude nickel and cobalt solution to obtain a first loaded organic phase loaded with nickel and cobalt and some impurities and a raffinate; Using a washing liquid to elute impurities in the first loaded organic phase to obtain a second loaded organic phase containing nickel, cobalt and copper impurities and a washing liquid; The nickel, cobalt and copper in the second loaded organic phase are stripped with a stripping solution to obtain a nickel-cobalt enriched solution containing copper impurities.

13. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 12, characterized in that: The extracted organic phase is obtained by mixing an extractant and a diluent and then saponifying with a saponifier; wherein the dilution rate of the extractant is 10-60%, the saponification rate is 20-70%, and the saponification level is 1-2.

14. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 13, characterized in that: The extractant is any one of HBL110, HBL116, Versatic10 and DY319 or a combination of at least two of them in any proportion; the diluent is kerosene No. 260 solvent oil or Escaid 110 solvent oil; the saponifier is any one of sodium hydroxide, nickel hydroxide and ammonia water or a combination of at least two of them.

15. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 12, characterized in that: In the nickel-cobalt co-extraction, the volume ratio of the extracted organic phase to the crude nickel-cobalt solution is 1:0.2-1, and the extraction stages are 2-12.

16. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 12, characterized in that: In the step of eluting impurities with the washing liquid, the volume ratio of the first loaded organic phase to the washing liquid is 1:0.1-1, the hydrogen ion concentration in the washing liquid is 0.05-1 mol / L, and the washing stage is 1-8; the washing liquid is added to the crude nickel-cobalt solution; The washing liquid includes sulfuric acid solution, hydrochloric acid solution, nitric acid, phosphoric acid, acetic acid or citric acid solution.

17. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 12, characterized in that: The volume ratio of the second loaded organic phase to the stripping solution is 1:0.05-1; the hydrogen ion concentration in the stripping solution is 1-4.5 mol / L, and the stripping stage is 1-8; The stripping solution includes sulfuric acid solution, hydrochloric acid solution, nitric acid, phosphoric acid, acetic acid or citric acid solution.

18. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 1, characterized in that: In step (4), the nickel-cobalt enriched solution is passed through a single resin column at a flow rate of 3 to 15 BV / h until the copper ion concentration in the adsorption tail liquid is less than 0.3 mg / L; the resin in the single resin column is a cation exchange resin KF320 or HP606.

19. The method for recovering battery-grade nickel and cobalt from laterite nickel ore in a short process according to claim 18, characterized in that: In step (4), the copper adsorption also includes a desorption process, and the desorption liquid is a sulfuric acid solution, hydrochloric acid solution, nitric acid, phosphoric acid or acetic acid solution with a mass concentration of 5 to 15%. During the desorption process, the flow rate of the desorption liquid is 1 to 4 BV / h. After the resin is desorbed, it directly enters the next round of copper adsorption process.

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