A method for co-treating waste gas and extracting waste lithium battery metal with organic amines

Abstract

This invention belongs to the field of metal extraction technology, and particularly relates to a method for the synergistic treatment of waste gas and extraction of waste lithium battery metals using organic amines. The method includes the following steps: selecting organic amines as raw materials, diluting and stirring them with water to obtain an organic amine aqueous solution, and preparing a leaching solution of waste lithium battery metals after impurity removal; injecting the obtained organic amine aqueous solution into an absorption tower, and introducing waste gas containing CO2 to generate a CO2-rich solution; adding the obtained CO2-rich solution to the waste lithium battery metal leaching solution, stirring to ensure a full reaction, and allowing it to stand to obtain a mixture containing nickel, manganese, and cobalt metal precipitates and a lithium-containing solution; the CO2-rich solution generated from carbon dioxide can be used for the extraction of nickel, manganese, cobalt, and lithium from waste lithium batteries, effectively saving regeneration energy consumption. The entire treatment process is highly efficient, the process flow is simple, and there is no secondary pollution.

Description

Technical Field

[0001] This invention belongs to the field of metal extraction technology, and in particular relates to a method for the synergistic treatment of waste gas and extraction of waste lithium battery metals by organic amines. Background Technology

[0002] In recent years, global climate change has become increasingly severe, with the continuous rise in greenhouse gas emissions, such as carbon dioxide (CO2), becoming a major factor contributing to global warming. Reducing greenhouse gas emissions has become an urgent task facing the world to effectively mitigate the adverse effects of climate change. Meanwhile, the rapid development of the new energy industry and the large-scale application of lithium-ion batteries in electric vehicles and energy storage have brought about a new environmental challenge: the disposal of spent batteries. Traditional methods for recycling metals from spent batteries, such as hydrometallurgy and pyrometallurgy, not only suffer from high energy consumption and complex processes but also result in high recycling costs, severely restricting the large-scale application of these technologies. Therefore, developing efficient and environmentally friendly new technologies for recycling metals from spent batteries is of significant strategic importance for reducing environmental pollution, improving resource utilization efficiency, and promoting sustainable development.

[0003] However, current mainstream CO2 treatment technologies, such as physical adsorption or chemical adsorption based on solid adsorbents (e.g., zeolites, activated carbon, metal-organic frameworks (MOFs)), while avoiding solvent evaporation and equipment corrosion, still face challenges such as low adsorption capacity, insufficient cycle stability, and high humidity sensitivity. In the field of waste battery recycling, traditional hydrometallurgical and pyrometallurgical processes suffer from high acid and alkali consumption, low metal separation efficiency, and severe environmental pollution. These technological bottlenecks not only increase operating costs but also limit their large-scale application. Therefore, developing an innovative technology that can simultaneously solve CO2 emission reduction and the resource utilization of waste batteries is of profound significance for promoting green and low-carbon transformation and the development of a circular economy. Summary of the Invention

[0004] This invention provides a method for the synergistic treatment of waste gas and extraction of waste lithium battery metals using organic amines, which mainly solves the problems of poor waste gas treatment effect and low recycling efficiency of waste lithium batteries.

[0005] To achieve the aforementioned objective, the present invention provides the following technical solution:

[0006] A method for co-treating waste gas and extracting waste lithium battery metal using organic amines includes the following steps:

[0007] S1: The organic amine aqueous solution absorbs CO2 from the waste gas to generate a CO2-rich solution. The CO2-rich solution is then added to the metal leaching solution of waste lithium batteries. After reaction and filtration, a solid containing nickel, manganese, and cobalt metals and a lithium-containing solution are obtained.

[0008] S2: Add sodium phosphate solution to lithium-containing solution, react and filter to obtain lithium phosphate solid; dissolve solid containing nickel, manganese and cobalt metals in sulfuric acid solution to form sulfuric acid solution containing nickel, manganese and cobalt metals;

[0009] S3: Add the ethanol solution of dimethylglyoxime to the obtained sulfuric acid solution containing nickel, manganese, and cobalt. After filtration, dimethylglyoxime-nickel solid and manganese-cobalt solution are obtained. Dimethylglyoxime-nickel solid serves as a precursor for MOFs.

[0010] S4: A kerosene solution of di(2-ethylhexyl) phosphate is added to the obtained manganese- and cobalt-containing solution to form a manganese-containing organic phase and a cobalt-containing aqueous phase. The mixture is then separated to obtain a cobalt-containing aqueous phase and a manganese-containing organic phase. Waste gas containing hydrogen sulfide is introduced into the cobalt-containing aqueous phase, and the reaction is filtered to form solid cobalt sulfide, which can be used as a precursor for ternary battery materials. The manganese-containing organic phase is added to a sulfuric acid solution for back-extraction to obtain a manganese sulfate solution and an organic phase. The organic phase is recycled, and the manganese sulfate solution is cooled, crystallized, filtered, and dried to obtain solid manganese sulfate.

[0011] Preferably, the metal leachate from the waste lithium battery in S1 is a leachate of hydrochloric acid or sulfuric acid.

[0012] Preferably, the organic amine in S1 is diethylene glycolamine, ethylenediamine, or triethylenetetramine.

[0013] Preferably, the concentration of the organic amine aqueous solution in S1 is 1 mol / L to 3 mol / L.

[0014] Preferably, the volume percentage of CO2 in S1 is 5% to 20%.

[0015] Preferably, the sodium phosphate solution in S2 has a mass fraction of 7% to 13%.

[0016] Preferably, the concentration of the sulfuric acid solution in S2 is 2.5 mol / L to 3.5 mol / L.

[0017] Preferably, the concentration of the dimethylglyoxime ethanol solution in S3 is 0.05 mol / L to 0.15 mol / L.

[0018] Preferably, the volume ratio of di(2-ethylhexyl) phosphate in the kerosene solution of S4 is 25% to 35%.

[0019] Preferably, the H2S concentration in the hydrogen sulfide waste gas in S4 is 50ppm to 200ppm.

[0020] The technical solution provided by this invention has at least the following technical effects:

[0021] The CO2-rich solution generated from treating carbon dioxide in waste gas can be used to extract nickel, manganese, cobalt, and lithium from spent lithium batteries, effectively saving regeneration energy. The final product, lithium phosphate, is widely used in lithium-ion battery materials, optical and electronic materials, industrial catalysis, and environmental protection. Cobalt sulfide and manganese sulfate can be used as precursors for ternary battery cathode materials, while dimethylglyoxime-nickel can be used as a precursor for MOFs. The entire treatment process is highly efficient, has a simple flow, and produces no secondary pollution. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the process flow of the present invention. Detailed Implementation

[0024] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. These embodiments are implemented based on the technical solution of the present invention, and detailed implementation methods and specific operation processes are given. However, the scope of protection of the present invention is not limited to the following embodiments.

[0025] A method for co-treating waste gas and extracting waste lithium battery metal using organic amines includes the following steps:

[0026] S1: Select organic amines as raw materials. The organic amines can be diethylene glycolamine, ethylenediamine, or triethylenetetramine, etc. After dilution and stirring with water, an organic amine aqueous solution is obtained. The concentration of the organic amine aqueous solution is 1 mol / L to 3 mol / L. Prepare a waste lithium battery metal leaching solution after impurity removal. The waste lithium battery metal leaching solution can be a leaching solution of hydrochloric acid or sulfuric acid.

[0027] The obtained organic amine aqueous solution is injected into the absorption tower, and waste gas containing CO2 is introduced to generate a CO2-rich solution; the volume percentage of CO2 is 5% to 20%; the basicity of the amine and the acidic oxide properties of CO2 undergo a reversible reaction, and through the combination of protons (H+) by the nitrogen atoms in the amine molecule, CO2 is converted into water-soluble carbonates, bicarbonates or carbamates, thereby enriching the solution with CO2.

[0028] The obtained CO2-rich solution was added to the metal leaching solution of waste lithium batteries, stirred to allow for complete reaction, and after standing, a mixture of precipitates containing nickel, manganese, and cobalt metals and a lithium-containing solution was obtained. Specifically, when the CO2-rich solution was added to the lithium battery metal leaching solution (usually acidic, as acid is often used to dissolve the cathode material during the leaching process), the pH of the solution would rise slightly due to the buffering effect of CO2, causing the above equilibrium to shift to the right and releasing more carbonate ions. ), provided by CO2-rich solution The metal leachate from waste lithium batteries mainly contains , , and After the reaction, stirring ensures sufficient contact between the ions and completes precipitation. Upon standing, the denser NiCO3, CoCO3, and MnCO3 precipitates will settle to the bottom, while... Since no precipitate was formed, it remained in the upper clear liquid, eventually forming a mixture of "metal precipitate + lithium-containing solution".

[0029] The mixture of the obtained nickel-, manganese-, and cobalt-containing metal precipitates and the lithium-containing solution was filtered to obtain a solid containing nickel-, manganese-, and cobalt metals and a lithium-containing solution.

[0030] S2: Add sodium phosphate solution (7%–13% by mass) to the obtained lithium-containing solution; stir thoroughly to ensure complete reaction, and allow to stand to obtain lithium phosphate precipitate; the lithium-containing solution contains… With sodium phosphate A metathesis reaction occurs, forming lithium phosphate precipitate:

[0031] 3Li + +PO4 3- →Li3PO4↓

[0032] The obtained lithium phosphate precipitate was filtered and dried to obtain solid lithium phosphate.

[0033] The obtained solid containing nickel, manganese, and cobalt metals is dissolved in sulfuric acid solution to form a sulfuric acid solution containing nickel, manganese, and cobalt; the concentration of the sulfuric acid solution is 2.5 mol / L to 3.5 mol / L.

[0034] S3: Dissolve dimethylglyoxime in ethanol to prepare a dimethylglyoxime ethanol solution, and add it to the obtained sulfuric acid solution containing nickel, manganese, and cobalt to form a mixture of dimethylglyoxime-nickel precipitate and manganese-cobalt solution; the concentration of the dimethylglyoxime ethanol solution is 0.05 mol / L to 0.15 mol / L; specifically, dimethylglyoxime (C4H8N2O2) and... The specific chelation reaction produces a bright red, insoluble dimethylglyoxime-nickel precipitate, while... , It does not react with dimethylglyoxime in a similar manner, thus enabling the separation of nickel from manganese and cobalt.

[0035] The mixture of the obtained dimethylglyoxime-nickel precipitate and the manganese and cobalt-containing solution was filtered and dried to obtain dimethylglyoxime-nickel solid and manganese and cobalt-containing solution. The dimethylglyoxime-nickel solid was used as a precursor of MOFs.

[0036] S4: Dissolve di(2-ethylhexyl) phosphate in sulfonated kerosene to prepare a kerosene solution of di(2-ethylhexyl) phosphate, and add it to the obtained manganese- and cobalt-containing solution to form a manganese-containing organic phase and a cobalt-containing aqueous phase; the volume ratio of di(2-ethylhexyl) phosphate to kerosene solution is 25%–35%; specifically, by utilizing the extraction selectivity of di(2-ethylhexyl) phosphate and the difference in the binding ability of metal ions and extractants, ... They form chelates that enter the organic phase, while Remaining in the aqueous phase enables efficient separation of manganese and cobalt.

[0037] The obtained manganese-containing organic phase and cobalt-containing aqueous phase were separated to obtain a cobalt-containing aqueous phase and a manganese-containing organic phase. Waste gas containing hydrogen sulfide was introduced into the cobalt-containing aqueous phase at a concentration of 50 ppm to 200 ppm to form cobalt sulfide precipitate. The H2S then provides... and By combining the formation of CoS precipitate, cobalt was separated from the solution. After filtration and drying, solid cobalt sulfide was obtained, which can be used as a precursor for ternary battery materials.

[0038] The obtained manganese-containing organic phase was added to a sulfuric acid solution for back-extraction to obtain a manganese sulfate solution and an organic phase. The organic phase was recycled, and the manganese sulfate solution was cooled, crystallized, filtered, and dried to obtain solid manganese sulfate.

[0039] Example 1: The concentration of diethylene glycolamine (DGA) was 3 mol / L, and the CO2 concentration in the waste gas was 20%. The absorbent was injected into the absorption tower, and the CO2-containing waste gas reacted with the absorbent in the absorption tower for 20 minutes. The CO2 absorption efficiency was measured to be 98%. The collected CO2-rich solution was used to extract nickel, manganese, cobalt, and lithium from waste lithium batteries. The extraction yields were 99.99% for lithium, 99.98% for manganese, 99.23% for nickel, and 99.44% for cobalt. The H2S concentration in the waste gas was 90 ppm, and the treatment efficiency was 99.8% after treatment. The final product, lithium phosphate (Li3PO4), can be used in lithium-ion battery materials, optical and electronic materials, industrial catalysis, and environmental protection. Cobalt sulfide (CoS) and manganese sulfate (MnSO4) can be used as precursors for ternary battery cathode materials, and dimethylglyoxime-nickel (DMG-Ni) can be used as a precursor for MOFs.

[0040] Example 2: The concentration of diethylene glycolamine (DGA) was 3 mol / L, and the CO2 concentration in the waste gas was 20%. The absorbent was injected into the absorption tower, and the CO2-containing waste gas reacted with the absorbent in the absorption tower for 20 minutes. The CO2 absorption efficiency was measured to be 98%. The collected CO2-rich solution was used to extract nickel, manganese, cobalt, and lithium from waste lithium batteries. The extraction yields were 99.99% for lithium, 99.98% for manganese, 99.23% for nickel, and 99.44% for cobalt. The H2S concentration in the waste gas was 90 ppm, and the treatment efficiency was 99.8% after treatment. The final product, lithium phosphate (Li3PO4), can be used in lithium-ion battery materials, optical and electronic materials, industrial catalysis, and environmental protection. Cobalt sulfide (CoS) and manganese sulfate (MnSO4) can be used as precursors for ternary battery cathode materials, and dimethylglyoxime-nickel (DMG-Ni) can be used as a precursor for MOFs.

[0041] Example 3: The concentration of diethylene glycolamine (DGA) was 1 mol / L, and the CO2 concentration in the waste gas was 10%. The absorbent was injected into the absorption tower, and the waste gas reacted with the absorbent in the absorption tower for 10 minutes. The CO2 absorption efficiency was measured to be 87%. The collected CO2-rich solution was used to extract nickel, manganese, cobalt, and lithium from waste lithium batteries. The extraction yields were 99.99% for lithium, 99.74% for manganese, 98.83% for nickel, and 98.95% for cobalt. The H2S concentration in the waste gas was 200 ppm, and the treatment efficiency was 99.1% after treatment. The final product, lithium phosphate (Li3PO4), can be used in lithium-ion battery materials, optical and electronic materials, industrial catalysis, and environmental protection. Cobalt sulfide (CoS) and manganese sulfate (MnSO4) can be used as precursors for ternary battery cathode materials, and dimethylglyoxime-nickel (DMG-Ni) can be used as a precursor for MOFs.

[0042] The implementation process of Examples 4 to 9 is the same as that of Example 1, and the implementation data is shown in Table 1.

[0043] Table 1: Implementation Data Tables for Examples 4 to 9

[0044]

[0045] In summary, the CO2-rich solution generated from treating carbon dioxide in waste gas can be used to extract nickel, manganese, cobalt, and lithium from spent lithium batteries, effectively saving regeneration energy consumption. The final product, lithium phosphate, is widely used in lithium-ion battery materials, optical and electronic materials, industrial catalysis, and environmental protection. Cobalt sulfide and manganese sulfate can be used as precursors for ternary battery cathode materials, while dimethylglyoxime-nickel can be used as a precursor for MOFs. The entire treatment process is highly efficient, has a simple flow, and produces no secondary pollution.

[0046] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of protection claimed by the present invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for co-treating waste gas and extracting waste lithium battery metal using organic amines, characterized in that, Includes the following steps: S1: The organic amine aqueous solution absorbs the CO2-containing waste gas to generate a CO2-rich solution. The CO2-rich solution is then added to the metal leaching solution of waste lithium batteries. After reaction and filtration, a solid containing nickel, manganese, and cobalt metals and a lithium-containing solution are obtained. S2: Add sodium phosphate solution to lithium-containing solution, react and filter to obtain lithium phosphate solid; dissolve solid containing nickel, manganese and cobalt metals in sulfuric acid solution to form sulfuric acid solution containing nickel, manganese and cobalt metals; S3: Add the ethanol solution of dimethylglyoxime to the obtained sulfuric acid solution containing nickel, manganese, and cobalt. After filtration, dimethylglyoxime-nickel solid and manganese-cobalt solution are obtained. Dimethylglyoxime-nickel solid serves as a precursor for MOFs. S4: A kerosene solution of di(2-ethylhexyl) phosphate is added to the obtained manganese- and cobalt-containing solution to form a manganese-containing organic phase and a cobalt-containing aqueous phase. The mixture is then separated to obtain a cobalt-containing aqueous phase and a manganese-containing organic phase. Waste gas containing hydrogen sulfide is introduced into the cobalt-containing aqueous phase, and the reaction is filtered to form solid cobalt sulfide, which is used as a precursor for ternary battery materials. The manganese-containing organic phase is added to a sulfuric acid solution for back-extraction to obtain a manganese sulfate solution and an organic phase. The organic phase is recycled, and the manganese sulfate solution is cooled, crystallized, filtered, and dried to obtain solid manganese sulfate.

2. The method for co-treating waste gas and extracting waste lithium battery metal using organic amines according to claim 1, characterized in that, The metal leaching solution from the waste lithium battery in S1 is a leaching solution of hydrochloric acid or sulfuric acid.

3. The method for co-treating waste gas and extracting waste lithium battery metal using organic amines according to claim 1, characterized in that, The organic amine in S1 is diethylene glycolamine, ethylenediamine, or triethylenetetramine.

4. The method for co-treating waste gas and extracting waste lithium battery metal using organic amines according to claim 1, characterized in that, The concentration of the organic amine aqueous solution in S1 is 1 mol / L to 3 mol / L.

5. The method for co-treating waste gas and extracting waste lithium battery metal using organic amines according to claim 1, characterized in that, The volume percentage of CO2 in S1 is 5% to 20%.

6. The method for co-treating waste gas and extracting waste lithium battery metal with organic amines according to claim 1, characterized in that, The sodium phosphate solution in S2 has a mass fraction of 7% to 13%.

7. The method for co-treating waste gas and extracting waste lithium battery metal with organic amines according to claim 1, characterized in that, The concentration of the sulfuric acid solution in S2 is 2.5 mol / L to 3.5 mol / L.

8. The method for co-treating waste gas and extracting waste lithium battery metal using organic amines according to claim 1, characterized in that, The concentration of the dimethylglyoxime ethanol solution in S3 is 0.05 mol / L to 0.15 mol / L.

9. The method for co-treating waste gas and extracting waste lithium battery metal with organic amines according to claim 1, characterized in that, The volume ratio of di(2-ethylhexyl) phosphate in the S4 solution to kerosene is 25%–35%.

10. The method for co-treating waste gas and extracting waste lithium battery metal using organic amines according to claim 1, characterized in that, The H2S concentration in the hydrogen sulfide waste gas in S4 is 50ppm to 200ppm.

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