Method for recovering nickel from nickel-containing iron solution

Abstract

A method for recovering nickel from a nickel-containing copper solution having a pH value of 0.5-3. The method comprises: step 1): performing a first solid phase extraction on the solution, and then performing solid-liquid separation, to obtain a first liquid phase having a pH value of ≤3.5, and a first solid phase; step 2): sequentially washing and stripping the first solid phase, to obtain a nickel-rich stripping solution and a first solid phase after stripping. The method has high nickel extraction efficiency, and has a good separation effect on nickel and impurities such as iron.

Description

Method for recovering nickel from nickel-containing ferrofluid Technical Field

[0001] The present invention relates to the technical field of metal recovery, and in particular to a method for recovering nickel from nickel-containing iron liquid. Background Art

[0002] The main sources of nickel are nickel-cobalt ore, nickel-cobalt intermediates, nickel-cobalt oxides, waste lithium-ion batteries, etc. The extraction and recovery of nickel from them has important economic and strategic value.

[0003] Resin solid-phase extraction (SPE) is a commonly used method for metal recovery in existing technologies. This method utilizes resins containing specific functional groups to extract metals. This method offers excellent metal selectivity, rapid phase separation, simple operation, and environmental friendliness.

[0004] However, the resin solid phase extraction method is not ideal for separating impurities such as nickel and iron. Therefore, a new method for effectively separating impurity metals such as nickel and iron is needed.

[0005] Summary of the Invention

[0006] An object of the present invention is to provide a method for effectively recovering nickel from a nickel-containing ferrofluid.

[0007] Therefore, the present invention provides a method for recovering nickel from a nickel-containing iron liquid having a pH value of 0.5-3, characterized in that it comprises:

[0008] Step 1): performing a first solid phase extraction on the feed liquid using a first extractant, and then performing solid-liquid separation to obtain a first liquid phase with a pH value of ≤3.5 and a first solid phase; and

[0009] Step 2): washing and stripping the first solid phase in sequence to obtain a nickel-rich stripping solution and the first solid phase after stripping,

[0010] in,

[0011] The first extractant comprises a chelating resin of formula (I):

[0012] in:

[0013] P is the base resin;

[0014] R1 and R2 are each independently a nitrogen-containing heterocyclic group;

[0015] M is

[0016] n and m are independently integers from 2 to 10; and

[0017] x is 0 or 1.

[0018] The method of the present invention has high nickel extraction efficiency and achieves good separation effect of nickel from impurities such as iron. DETAILED DESCRIPTION

[0019] Various aspects of the invention as well as further objects, features and advantages will appear more fully hereinafter.

[0020] As described above, the present invention provides a method for recovering nickel from a nickel-containing iron liquid having a pH value of 0.5-3, characterized in that it comprises:

[0021] Step 1): performing a first solid phase extraction on the feed liquid using a first extractant, and then performing solid-liquid separation to obtain a first liquid phase with a pH value of ≤3.5 and a first solid phase; and

[0022] Step 2): washing and stripping the first solid phase in sequence to obtain a nickel-rich stripping solution and the first solid phase after stripping,

[0023] in,

[0024] The first extractant comprises a chelating resin of formula (I):

[0025] in:

[0026] P is the base resin;

[0027] R1 and R2 are each independently a nitrogen-containing heterocyclic group;

[0028] M is

[0029] n and m are independently integers from 2 to 10; and

[0030] x is 0 or 1.

[0031] The nickel-iron-containing liquid can be, for example, an aqueous dispersion or an aqueous solution.

[0032] Advantageously, the feed solution contains 0.1-20 g / L Ni, preferably 0.1-10 g / L Ni, calculated by weight relative to the volume of the feed solution.

[0033] Advantageously, the feed solution contains 0.1-120 g / L of Fe, preferably 1-80 g / L of Fe, calculated by weight relative to the volume of the feed solution.

[0034] In some embodiments, the feed solution further comprises Cu ≤ 15 g / L, preferably ≤ 10 g / L, by weight relative to the volume of the feed solution.

[0035] When the feed liquid contains copper, preferably, the copper is first extracted and removed, that is, a second solid phase extraction is performed on the feed liquid using a second extractant, and then solid-liquid separation is performed to obtain a second liquid phase and a second solid phase, and then the first solid phase extraction is performed on the second liquid phase.

[0036] Preferably, the pH value of the first liquid phase is in the range of 0.7-3.5.

[0037] Preferably, the second extractant in the present invention comprises a chelate resin selected from the group consisting of a chelate resin of formula (I), a chelate resin of formula (II), a chelate resin of formula (III), a chelate resin of formula (IV), an iminodiacetic acid chelate resin, and combinations thereof:

[0038] in:

[0039] P is the base resin;

[0040] R1 and R2 are each independently a nitrogen-containing heterocyclic group;

[0041] R3 is an acyl group;

[0042] M is

[0043] n and m are independently integers from 2 to 10; and

[0044] x is 0 or 1.

[0045] Advantageously, the pH value of the second liquid phase is controlled to be 0.5-3, so as to be used as the feed liquid in step 1).

[0046] After solid phase extraction with the second extractant, the method of the present invention can achieve sufficient removal of copper. In some embodiments, the pH value of the second liquid phase is controlled to be 0.5-1.

[0047] In some embodiments, the feed solution comprises ≤ 20 g / L Co by weight relative to the volume of the feed solution.

[0048] In some embodiments, the feed solution may optionally further comprise one or more of Mn, Zn, Cd, Cr, Al, Ca, Mg, Li, Ti, Si, and F.

[0049] In some embodiments, the feed solution comprises Cd≤10 g / L and / or Zn≤10 g / L, by weight relative to the volume of the feed solution.

[0050] In some embodiments, the first extractant further comprises a chelating resin of formula (II) above.

[0051] In some embodiments, the second extractant is the same as the first extractant.

[0052] Preferably, the second extractant comprises a chelating resin of formula (II).

[0053] In some embodiments, the second extractant is a chelate resin of formula (II), and the first extractant consists of a chelate resin of formula (I) and a chelate resin of formula (II).

[0054] Preferably, the molar ratio of the chelate resin of formula (I) to the chelate resin of formula (II) in the first extractant is not less than 0.6:1, and in some embodiments the ratio is in the range of 1-5:1.

[0055] In some embodiments, the second extractant comprises a chelating resin of formula (I) and a chelating resin of formula (II).

[0056] In some embodiments, the second extractant consists of a chelating resin of formula (I) and a chelating resin of formula (II).

[0057] In some embodiments, in the second extractant, the molar ratio of the chelate resin of formula (I) to the chelate resin of formula (II) is not less than 0.6:1, and in some embodiments the ratio is in the range of 1-5:1. In some embodiments, the second extractant consists of the chelate resin of formula (I) and the chelate resin of formula (II), and the first extractant consists of the chelate resin of formula (I) and the chelate resin of formula (II), preferably, the molar ratio of the chelate resin of formula (I) to the chelate resin of formula (II) in the second extractant is in the range of 1-5:1 and / or the molar ratio of the chelate resin of formula (I) to the chelate resin of formula (II) in the first extractant is in the range of 1-5:1.

[0058] In some embodiments, the second extractant comprises a chelating resin of formula (I) and a chelating resin of formula (III).

[0059] In some embodiments, the second extractant consists of a chelating resin of formula (I) and a chelating resin of formula (III).

[0060] In some embodiments, in the second extractant, the molar ratio of the chelate resin of formula (I) to the chelate resin of formula (III) is not less than 0.6:1, and in some embodiments the ratio is in the range of 1-5:1. In some embodiments, the second extractant consists of the chelate resin of formula (I) and the chelate resin of formula (III), and the first extractant consists of the chelate resin of formula (I) and the chelate resin of formula (II), preferably, the molar ratio of the chelate resin of formula (I) to the chelate resin of formula (III) in the second extractant is in the range of 1-5:1 and / or the molar ratio of the chelate resin of formula (I) to the chelate resin of formula (II) in the first extractant is in the range of 1-5:1.

[0061] The present invention does not particularly limit the base resin P. Preferably, the base resin P is selected from polystyrene resin, a copolymer of styrene and divinylbenzene, a phenolic resin polymer, a polyacrylic resin, and a silicon-based resin. More preferably, the base resin P is selected from polystyrene resin and a copolymer of styrene and divinylbenzene.

[0062] Specifically, n and m are independently 2, 3, 4, 5, 6, 7, 8, 9 or 10.

[0063] Preferably, the nitrogen-containing heterocyclic groups R1 and R2 are each independently selected from a pyridine group, an imidazole group, a benzimidazole group, a pyrazole group, a quinoline group, a pyrazine group, a triazine group and a triazole group.

[0064] More specifically, the nitrogen-containing heterocyclic groups R1 and R2 are each independently selected from the following groups:

[0065] Preferably, the nitrogen-containing heterocyclic groups R1 and R2 are each independently selected from the following groups:

[0066] Preferably, R3 is -(CO)R4 or -CH2(CO)R4, wherein R4 is a straight chain or branched alkyl group with a carbon chain number of 1-5, -N-(R5)2 or a nitrogen-containing heterocyclic group defined for R1 or R2, wherein R5 is a straight chain or branched alkyl group with a carbon chain number of 1-5.

[0067] More specifically, the chelating resin of formula (I) has a structure selected from the group consisting of:

[0068] Wherein P is independently selected from polystyrene resin, copolymer of styrene and divinylbenzene, phenolic resin polymer, polyacrylic resin and silicon-based resin.

[0069] More preferably, the chelating resin of formula (I) has a structure selected from the following:

[0070] Wherein P is independently selected from polystyrene resin, copolymer of styrene and divinylbenzene. Preferably, the chelating resin of formula (II) has a structure selected from the following:

[0071] Wherein P is independently selected from polystyrene resin, copolymer of styrene and divinylbenzene, phenolic resin polymer, polyacrylic resin and silicon-based resin.

[0072] More preferably, the chelating resin of formula (II) has a structure selected from the following:

[0073] Wherein P is independently selected from polystyrene resin, styrene-based copolymers and divinylbenzene. Preferably, the chelating resin of formula (III) has a structure selected from the following:

[0074] Wherein P is independently selected from polystyrene resin, copolymer of styrene and divinylbenzene, phenolic resin polymer, polyacrylic resin and silicon-based resin.

[0075] Furthermore, the solid-liquid ratio of the second extractant to the feed liquid is 1 g:1-30 mL, preferably 1 g:1-10 mL.

[0076] Furthermore, the second solid phase extraction is countercurrent and / or crosscurrent extraction, preferably countercurrent extraction. Furthermore, the number of extraction stages is 1-10, preferably 2-8.

[0077] Furthermore, the extraction mixing time in the second solid phase extraction is 10-60 min, more preferably 20-50 min.

[0078] Furthermore, in step 1), the first solid phase extraction is countercurrent and / or crosscurrent extraction, preferably countercurrent extraction.

[0079] Furthermore, the number of extraction stages in the first solid phase extraction is 1-15, preferably 2-8.

[0080] Furthermore, in step 1), the solid-liquid ratio of the first extractant to the feed liquid or the second liquid phase is 1 g:0.5-30 mL, preferably 1 g:0.8-10 mL.

[0081] Furthermore, in step 1), the mixing time in the first solid phase extraction is 10-60 min, more preferably 20-50 min.

[0082] Furthermore, the washing in step 2) is countercurrent and / or crosscurrent washing, and the number of washing stages is 1-20, preferably 2-15.

[0083] Furthermore, the pH value of the washing liquid used to wash the first solid phase is 0.5-7, more preferably 0.5-2. Preferably, the ratio of the washing liquid to the first solid phase is 0.2-10 mL:1 g, and the washing time is 10-60 min, more preferably 20-50 min.

[0084] Preferably, the second solid phase is stripped after multi-stage countercurrent washing to obtain a copper-containing solution and the second solid phase after stripping, which are then returned for use as an extractant after regeneration, and the pH value of the regenerated effluent is controlled to be 0.5-3.0.

[0085] Furthermore, the washing of the second solid phase is countercurrent and / or crosscurrent washing, and the number of washing stages is 1-20, preferably 2-15.

[0086] Furthermore, the pH value of the washing solution used for washing the second solid phase is 0.5-7, more preferably 0.5-2. The ratio of the washing solution to the second solid phase is 0.2-10 mL:1 g, and the washing time is 10-60 min, more preferably 20-50 min.

[0087] In the present invention, the back extraction can be performed using an acid solution; the acid solution includes sulfuric acid and / or hydrochloric acid. The ratio of the acid solution used in the back extraction to the first solid phase or the second solid phase is 0.2-10 mL:1 g, the back extraction time is 10-60 min, more preferably 20-50 min, the concentration of the hydrochloric acid used in the back extraction is 1-8 mol / L, and the concentration of the sulfuric acid used in the back extraction is 0.5-6 mol / L, more preferably 2-3 mol / L.

[0088] Preferably, the method of the present invention further comprises regenerating the first solid phase after stripping after step 2), and the pH value of the regenerated water is controlled to be 0.5-7, preferably 0.5-3.0.

[0089] The regeneration agent used in the regeneration of the present invention is not particularly limited. Preferably, the regeneration agent includes one or a combination of at least two of water, sodium hydroxide solution, ammonia water, sodium carbonate solution, nickel salt solution, cobalt salt solution, nickel hydroxide suspension, cobalt hydroxide suspension, magnesium oxide suspension or lime suspension.

[0090] More preferably, one or a combination of at least two selected from pure water, tap water, and soft water is used as a regeneration agent to regenerate the first solid phase after stripping.

[0091] The method of the present invention has a good effect on separating metal ions. By controlling the extraction pH value, the separation and recovery of nickel by the nitrogen-containing heterocyclic resin is achieved. The method has a good separation effect from impurity ions, is simple to operate, and has low process cost.

[0092] The method of the invention ensures that the removal rate of impurity copper (if present) is greater than or equal to 99%, the nickel recovery rate is greater than or equal to 98%, and the nickel-iron ratio in the nickel-rich stripping solution is not less than 350.

[0093] In addition, the resin used in the method of the present invention can be recycled and reused, the operation cost is low, and the method has good economic benefits.

[0094] In this application, the term "and / or" covers situations involving one or both of the mentioned elements. In this application, the terms "include" and "comprise" cover situations involving other elements not explicitly mentioned as well as situations consisting of the mentioned elements.

[0095] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the invention belongs. When the definition of a term in this specification conflicts with the meaning commonly understood by those skilled in the art to which the invention belongs, the definition described in this article shall prevail.

[0096] Unless otherwise indicated, all numbers expressing amounts of ingredients, temperatures, times, and so forth used in the specification and claims are to be understood as being modified by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth herein are approximations that can vary depending upon the desired properties sought to be obtained.

[0097] Example

[0098] The following will further illustrate the concept, specific structure and technical effects of the present invention in conjunction with the embodiments, so that those skilled in the art can fully understand the purpose, features and effects of the present invention. It will be readily understood by those skilled in the art that the embodiments herein are for illustrative purposes only and the scope of the present invention is not limited thereto.

[0099] Example 1

[0100] The feed liquid in this embodiment is a nickel-ferroconcentrated feed liquid, the pH value of the feed liquid is 1.3, and it contains the following components:

[0101] The first extractant (the structural formula of which the molar ratio is 3:1) is used The feed liquid is subjected to 5-stage countercurrent extraction using a chelating resin composition, wherein P is a polystyrene resin microsphere, the extraction equipment is a continuous ion exchange resin column, the ratio of the first extractant to the feed liquid is 1 g:1 mL, the mixing time is 30 min, and a solid phase 1 and an aqueous phase 1 with a pH value of 1.15 are obtained. The solid phase 1 was subjected to 10-stage countercurrent washing with a sulfuric acid solution having a pH value of 0.8, with the ratio of the washing liquid to the solid phase 1 being 1.5 mL:1 g and the mixing time being 30 min to obtain the washed solid phase 1. A 2.5 mol / L sulfuric acid solution was then used for 4-stage countercurrent stripping, with the ratio of the stripping liquid to the washed solid phase 1 being 1.5 mL:1 g and the mixing time being 30 min to obtain the stripped solid phase 1 and the stripped liquid. The washed liquid obtained by washing was recycled for multiple uses and then incorporated into the feed liquid. The stripped liquid was recycled for multiple uses until the nickel concentration in the stripping liquid reached 30 g / L to obtain a nickel-cobalt-rich stripping liquid, which was evaporated and concentrated to obtain nickel sulfate and cobalt sulfate. The stripped solid phase 1 was washed with a 0.5% lime suspension until the pH value of the effluent was 1.5 and then recycled.

[0102] In this embodiment, the recovery rates of Ni and Co are 98.9% and 27.6% respectively, and the ratio of nickel to iron impurity elements in the nickel-cobalt-rich stripping solution is 350.

[0103] Example 2

[0104] The feed liquid in the present embodiment is nickel iron liquid, and the pH value of the feed liquid is 1.0, and contains the following components:

[0105] The second extractant (the structural formula of which the molar ratio is 4:1) is used The invention relates to a method for preparing the present invention. The method comprises the following steps: a first step cross-current extraction of the feed liquid and a second step cross-current extraction of the feed liquid; a fixed-bed resin column is used for the extraction; the ratio of the second extractant to the feed liquid is 1 g: 20 mL; and the mixing time is 60 min. After the extraction is completed, a solid phase 2 and an aqueous phase 2 with a pH value of 0.95 are obtained. After the resin column reaches saturated extraction, a sulfuric acid solution with a pH value of 1.0 is used to wash the solid phase 2 with a first step cross-current, the ratio of the washing liquid to the solid phase 2 is 0.5 mL: 1 g; and the mixing time is 20 min. Then, a 6 mol / L sulfuric acid solution is used for back extraction 3 times, and the ratio of the stripping liquid to the washed solid phase 2 is 0.5 mL: 1 g; and the mixing time is 20 min. The solid phase 2 after back extraction and the back stripping liquid are obtained. The washed liquid after washing is circulated and used multiple times and then incorporated into the feed liquid. The back stripping liquid is circulated and used multiple times to obtain a copper sulfate solution after the copper concentration in the stripping liquid reaches 20 g / L. Metallic copper is then prepared by electrowinning.

[0106] The solid phase 2 after stripping is washed with pure water until the pH value of the effluent is 1.0 and then recycled.

[0107] The first extractant (the structural formula of which the molar ratio is 2.5:1) is used The aqueous phase 2 is subjected to 5-stage countercurrent extraction using a chelating resin composition, wherein P is a polystyrene resin microsphere. The extraction equipment adopts a centrifugal extraction equipment, the ratio of the first extractant to the aqueous phase 2 is 1g:10mL, the mixing time is 30min, and solid-liquid separation is performed to obtain a solid phase 1 and an aqueous phase 1 with a pH value of 0.8.

[0108] The solid phase 1 is subjected to 8-stage countercurrent washing with a sulfuric acid solution having a pH value of 1, and then stripped 4 times with a 2 mol / L sulfuric acid solution. The ratio of the washing liquid or stripping liquid to the solid phase 1 is 1 mL:1 g, and the mixing time is 30 min. The stripped solid phase 1 and the stripped liquid are obtained. The washed liquid obtained by washing is recycled for multiple times and then incorporated into the feed liquid. The stripped liquid is recycled for multiple times until the nickel concentration in the stripping liquid reaches 30 g / L to obtain a nickel-rich stripping liquid. Nickel sulfate is obtained after evaporation and concentration. The stripped solid phase 1 is washed with pure water until the pH value of the effluent is 1.0 and then recycled.

[0109] In this embodiment, the copper removal rate is 99.6%; the Ni recovery rate is 99.1%, and the ratio of nickel to iron in the nickel-rich stripping solution is 560.

[0110] Example 3

[0111] The feed solution in this embodiment is a battery feed solution containing nickel and cobalt. The pH value of the feed solution is 3.0 and contains the following metal components:

[0112] The second extractant (the structural formula of which the molar ratio is 3:1) is used The invention relates to a method for preparing the present invention, wherein the feed liquid is subjected to 2-stage countercurrent extraction by using a chelating resin, wherein P is a polystyrene resin microsphere, and the feed liquid is subjected to 2-stage countercurrent extraction. The extraction equipment is a fixed-bed resin column, the ratio of the second extractant to the feed liquid is 1g:2.5mL, and the mixing time is 25min. After the extraction is completed, a solid phase 2 and an aqueous phase 2 with a pH value of 2.0 are obtained. After the resin column reaches saturated extraction, the solid phase 2 is subjected to 3-stage cross-current washing by a sulfuric acid solution with a pH value of 2, and then 2.5mol / L sulfuric acid solution is adopted for back extraction 4 times. The ratio of the washing solution or the back extraction solution to the solid phase 2 is 5mL:1g, and the mixing time is 60min. The back extraction solid phase 2 and the back extraction liquid are obtained. The washing liquid obtained by washing is circulated and used multiple times and then incorporated into the feed liquid. The back extraction liquid is circulated and used multiple times to obtain a copper sulfate solution after the copper concentration in the back extraction solution reaches 20g / L, and copper sulfate is obtained by evaporation and concentration.

[0113] The solid phase 2 after stripping is washed with pure water until the pH value of the effluent is 2 and then recycled.

[0114] The first extractant (the structural formula of which the molar ratio is 2:1) is used The aqueous phase 2 is subjected to 8-stage countercurrent extraction, the extraction equipment is a centrifugal extraction equipment, the ratio of the first extractant to the aqueous phase 2 is 1g:0.8mL, the mixing time is 40min, and the solid-liquid separation is performed to obtain a solid phase 1 and an aqueous phase 1 with a pH value of 1.5.

[0115] The solid phase 1 was subjected to 15-stage countercurrent washing with a sulfuric acid solution having a pH value of 2.5, and then stripped 3 times with a 3 mol / L sulfuric acid solution. The ratio of the washing liquid or stripping liquid to the solid phase 1 was 0.5 mL:1 g, and the mixing time was 20 min. The washed liquid obtained by washing was recycled for multiple times and then incorporated into the feed liquid. The stripping liquid obtained by stripping was recycled for multiple times until the nickel concentration in the stripping liquid reached 30 g / L to obtain a nickel-rich stripping liquid, which was evaporated and concentrated to obtain nickel sulfate. The solid phase 1 after stripping was washed with pure water until the pH value of the effluent was 0.5 and then recycled.

[0116] In this embodiment, the copper removal rate is 99.4%; the Ni recovery rate is 99.0%, and the ratio of nickel to iron and zinc in the nickel-rich stripping solution is 2500.

[0117] Example 4

[0118] The feed solution in this embodiment is a nickel-cobalt-containing feed solution with a pH value of 0.75 and contains the following metal components:

[0119] The second extractant (structural formula is wherein, P is a copolymer of styrene and divinylbenzene) the feed liquid is subjected to 4-stage countercurrent extraction, the extraction equipment is a fixed bed resin column, the ratio of resin 1 to the feed liquid is 1g:1mL, the mixing time is 30min, and the extraction is completed to obtain a solid phase 2 and an aqueous phase 2 with a pH value of 0.72. After the resin column reaches extraction saturation, the solid phase 2 is subjected to 2-stage countercurrent washing with pure water, and then stripped 3 times with a 3mol / L sulfuric acid solution, the ratio of the washing liquid and the stripping liquid to the solid phase 2 is 1mL:1g, and the mixing time is 30min. The obtained washed liquid is recycled for multiple uses and then incorporated into the feed liquid. The obtained stripping liquid is recycled for multiple uses until the copper concentration in the stripping liquid reaches 20g / L to obtain a copper sulfate solution, which is evaporated and concentrated to obtain copper sulfate.

[0120] The solid phase 2 after stripping is washed with 1% sodium carbonate solution until the pH value of the effluent is 3.0 and then recycled. The aqueous phase 2 is subjected to three-stage countercurrent extraction, the extraction equipment is a centrifugal extraction equipment, the ratio of the first extractant to the copper-removed feed liquid is 1g:10mL, the mixing time is 25min, and the solid-liquid separation is performed to obtain a solid phase 1 and an aqueous phase 1 with a pH value of 0.7.

[0121] The solid phase 1 is subjected to six-stage countercurrent washing with a sulfuric acid solution having a pH value of 1, and then stripped four times with a 1.5 mol / L sulfuric acid solution. The ratio of the washing liquid or stripping liquid to the solid phase 1 is 0.5 mL:1 g, and the mixing time is 25 min. The washed liquid obtained by washing is recycled for multiple times and then incorporated into the feed liquid. The stripping liquid obtained by stripping is recycled for multiple times and is used until the nickel concentration in the stripping liquid reaches 30 g / L to obtain a nickel-rich stripping liquid. Nickel sulfate is obtained after evaporation and concentration. The solid phase 1 after stripping is washed with pure water until the pH value of the effluent is 2.5 and then recycled.

[0122] In this embodiment, the copper removal rate is 99.5%; the Ni recovery rate is 99.3%, and the ratio of nickel to iron impurity elements in the nickel-rich stripping solution is 380.

[0123] Example 5

[0124] The difference from Example 4 is that the second extractant

[0125] The structural formula with a molar ratio of 1:1 is P is a polystyrene resin microsphere.

[0126] In this embodiment, the copper removal rate is 99.4%, the Ni recovery rate is 99.3%, and the ratio of nickel to iron impurity elements in the nickel stripping solution is 400.

[0127] Example 6

[0128] The difference from Example 3 is that the pH value of aqueous phase 2 is adjusted to 1.1 using sulfuric acid, the first extractant is saponified using 2% sodium hydroxide, the pH value of the saponified liquid is controlled to 7, and the saponified first extractant is obtained and then extracted, resulting in aqueous phase 1 with a pH value of 3.5.

[0129] In this embodiment, the recovery rate of Ni is 99.4%, and the ratio of nickel to iron impurity elements in the nickel stripping solution is 380.

[0130] Example 7

[0131] The feed solution in this embodiment is a nickel-cobalt-containing feed solution with a pH value of 0.5 and contains the following metal components:

[0132] The first extractant (the structural formula of which is 3:1 in a molar ratio) is treated with 4% ammonia water. The chelating resin is composed of a chelating resin, wherein P is a polystyrene resin microsphere) and the pH value of the saponified liquid is controlled to be 5 to obtain the saponified first extractant. The feed liquid is subjected to two-stage countercurrent extraction, the extraction equipment is a centrifugal extraction equipment, the ratio of the first extractant to the feed liquid is 1g:30mL, the mixing time is 60min, and the solid-liquid separation is performed to obtain a solid phase 1 and an aqueous phase 1 with a pH value of 1.0.

[0133] The solid phase 1 is subjected to 8-stage countercurrent washing with a sulfuric acid solution having a pH value of 1, and then stripped 3 times with a 3 mol / L sulfuric acid solution. The ratio of the washing liquid or stripping liquid to the solid phase 1 is 2 mL:1 g, and the time is 40 min. The washed liquid obtained by washing is recycled for multiple times and then incorporated into the feed liquid. The stripping liquid obtained by stripping is recycled for multiple times and is used until the nickel concentration in the stripping liquid reaches 30 g / L to obtain a nickel-rich stripping liquid. Nickel sulfate is obtained after evaporation and concentration. The solid phase 1 after stripping is washed with pure water until the pH value of the effluent is 1.5 and then recycled.

[0134] In this embodiment, the recovery rate of Ni is 99.1%, and the ratio of nickel to iron impurity elements in the nickel-rich stripping solution is greater than 400.

[0135] The above merely describes exemplary embodiments or examples of the present invention and is not intended to limit the present invention. It will be apparent to those skilled in the art that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are intended to be included within the scope of the claims of this application.

Claims

1. A method for recovering nickel from a nickel-containing iron liquid having a pH value of 0.5-3, characterized in that: include: Step 1): using a first extractant to perform a first solid phase extraction on the feed liquid, and then performing solid-liquid separation to obtain a first liquid phase and a first solid phase with a pH value of ≤3.5; and Step 2): washing and stripping the first solid phase in sequence to obtain a nickel-rich stripping solution and the first solid phase after stripping, in, The first extractant comprises a chelating resin of formula (I) and a chelating resin of formula (II): in: P is the base resin; R1 and R2 are each independently selected from: R3 is -(CO)R4 or -CH2(CO)R4, wherein R4 is a straight chain or branched chain alkyl group having a carbon chain number of 1 to 5, or -N-(R5)2, wherein R5 is a straight chain or branched chain alkyl group having a carbon chain number of 1 to 5; M is n and m are independently integers from 2 to 10; and x is 0, In the first extractant, the molar ratio of the chelating resin of formula (I) to the chelating resin of formula (II) is in the range of 1-5:

1.

2. The method according to claim 1, characterized in that The feed solution contains Ni 0.1-20 g / L, calculated by weight relative to the volume of the feed solution.

3. The method according to claim 1, characterized in that The feed liquid further comprises Cu, and the method further comprises performing a second solid phase extraction on the feed liquid with a second extractant before performing solid phase extraction with the first extractant, then performing solid-liquid separation to obtain a second liquid phase and a second solid phase, and then performing a first solid phase extraction on the second liquid phase with the first extractant, wherein the second extractant comprises a chelate resin selected from the group consisting of a chelate resin of formula (I), a chelate resin of formula (II), a chelate resin of formula (III), a chelate resin of formula (IV), an iminodiacetic acid chelate resin, and a combination thereof: in: P is the base resin; R1 and R2 are each independently a nitrogen-containing heterocyclic group; R3 is an acyl group; M is n and m are independently integers from 2 to 10; and x is 0 or 1.

4. The method according to claim 3, characterized in that The second extractant comprises chelate resins of formula (I) and formula (II), wherein the molar ratio of the chelate resin of formula (I) to the chelate resin of formula (II) is in the range of 1-5:

1.

5. The method according to claim 3, characterized in that: The second extractant comprises chelate resins of formula (I) and formula (III), wherein the molar ratio of the chelate resin of formula (I) to the chelate resin of formula (III) is in the range of 1-5:

1.

6. The method according to any one of claims 1 to 5, characterized in that The base resin P is selected from polystyrene resin, copolymer of styrene and divinylbenzene, phenolic resin polymer, polyacrylic resin and silicon-based resin.

7. The method according to claim 3, characterized in that For the second extractant, the nitrogen-containing heterocyclic groups R1 and R2 are each independently selected from a pyridine group, an imidazole group, a benzimidazole group, a pyrazole group, a quinoline group, a pyrazine group, a triazine group and a triazole group, and R3 is -(CO)R4 or -CH2(CO)R4, wherein R4 is a straight chain or branched alkyl group having a carbon chain number of 1-5, -N-(R5)2 or a nitrogen-containing heterocyclic group defined for R1 or R2, wherein R5 is a straight chain or branched alkyl group having a carbon chain number of 1-5.

8. The method according to claim 3, characterized in that For the second extractant, the nitrogen-containing heterocyclic groups R1 and R2 are each independently selected from the following groups: R3 is -(CO)R4 or -CH2(CO)R4, wherein R4 is a straight chain or branched chain alkyl group having a carbon chain number of 1-5, or -N-(R5)2, wherein R5 is a straight chain or branched chain alkyl group having a carbon chain number of 1-5.

9. The method according to any one of claims 1 to 5, characterized in that For the second extractant, the chelating resin of formula (I) has a structure selected from the following: The chelating resin of formula (II) has a structure selected from the following: The chelating resin of formula (III) has a structure selected from the following: Wherein P is independently selected from polystyrene resin, copolymer of styrene and divinylbenzene, phenolic resin polymer, polyacrylic resin and silicon-based resin.

10. The method according to claim 3, characterized in that The second solid phase extraction is a combination of one or both of countercurrent extraction and cross-current extraction, the extraction level is 1-10, the solid-liquid ratio of the second extractant to the feed liquid is 1g:1-30mL, and the extraction mixing time in the second solid phase extraction is 10-60min.

11. The method according to any one of claims 1 to 5, characterized in that The first solid phase extraction is a combination of one or both of countercurrent extraction and cross-current extraction, the extraction level in the first solid phase extraction is 1-15, the solid-liquid ratio of the first extractant to the feed liquid or the second liquid phase described in claim 3 is 1g:0.5-30mL, and the mixing time in the first solid phase extraction is 10-60min.

12. The method according to any one of claims 1 to 5, characterized in that The washing in step 2) is one or a combination of countercurrent washing and crosscurrent washing, and the number of washing stages is 1-20, or The pH value of the washing liquid used to wash the first solid phase is 0.5-7, the ratio of the washing liquid to the first solid phase is 0.2-10mL:1g, and the washing time is 10-60min.

13. The method according to claim 3, characterized in that The second solid phase is stripped after multi-stage countercurrent washing to obtain a copper-containing solution and the second solid phase after stripping, and the second solid phase after stripping is regenerated, and the pH value of the regenerated water is controlled to be 0.5-3.

0.

14. The method according to claim 13, characterized in that The second solid phase is washed by countercurrent washing or crosscurrent washing or a combination of both, the washing stages are 1-20, the pH value of the washing liquid used for washing the second solid phase is 0.5-7, and the ratio of the washing liquid to the second solid phase is 0.2-10mL:1g.

15. The method according to any one of claims 1 to 5 and 13, characterized in that The stripping in step 2) or claim 13 is carried out using an acid solution; the acid solution comprises sulfuric acid or hydrochloric acid, the concentration of the hydrochloric acid is 1-8 mol / L, the concentration of the sulfuric acid is 0.5-6 mol / L, and the ratio of the acid solution to the first solid phase or the second solid phase in claim 13 is 0.2-10 mL: 1 g.

16. The method according to any one of claims 1 to 5, characterized in that The method further comprises regenerating the first solid phase after stripping after step 2), wherein the pH value of the regenerated water is controlled to be 0.5-7.

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