Imidazole derivative-organic phosphoric acid combined extractant and application method thereof

Abstract

The invention discloses an imidazole derivative-organic phosphoric acid combined extracting agent and an application method thereof, and belongs to the technical field of hydrometallurgy. The molar ratio of the imidazole derivative to the organic phosphoric acid is (10: 1)-(1: 10). The combined extraction agent can be used for extracting nickel, cobalt and manganese from a solution containing one or more nickel, cobalt and manganese. The selectivity of the solvent extraction system to nickel, cobalt and manganese is far higher than that of impurity metal ions such as calcium, magnesium, lithium, sodium and potassium, the extraction system is good in stability, free of emulsification phenomenon and third phase generation, easy to operate, low in cost and environmentally friendly. In lithium battery recovery and other systems containing coexistence of nickel, cobalt, manganese and calcium, magnesium and lithium, the solvent extraction system is particularly good in selectivity, and efficient co-extraction of nickel, cobalt and manganese can be achieved. When a mixed solution and a weak acid solution are treated, purification and concentration of target metal can be synchronously achieved, the recovery period is greatly shortened, the recovery rate is increased, and the method has great significance in efficient utilization of nickel-cobalt-manganese resources.

Description

Technical Field

[0001] This invention belongs to the field of hydrometallurgical technology, specifically the field of metal extraction, and more specifically, to an imidazole derivative-organophosphate combined extractant and its application in nickel-cobalt-manganese extraction. Background Technology

[0002] As crucial transition metals, nickel, cobalt, and manganese hold an irreplaceable core position in fields such as lithium-ion battery technology (driving the electric vehicle and energy storage revolution), aerospace high-temperature alloys, high-end stainless steel, and special alloys. In lithium-ion batteries, nickel, cobalt, and manganese play an indispensable role in improving battery energy density, stabilizing structure, and controlling costs. With the development of electric vehicles, the amount of waste lithium batteries is increasing year by year. Waste lithium batteries contain nickel, cobalt, manganese, and calcium-magnesium-lithium compounds. The presence of impurity ions such as calcium and magnesium ions affects battery life and performance, making the simultaneous recycling of nickel, cobalt, and manganese from waste lithium batteries an urgent priority. Developing efficient, economical, and environmentally friendly extraction and separation technologies is also a significant challenge currently facing the industry.

[0003] Nickel, cobalt, and manganese rarely exist in nature in their elemental form, but are mainly found in various ores and minerals. They can exist in independent deposits, and often appear as associated elements in other metallic ores (especially cobalt and manganese). Currently, the main sources of nickel, cobalt, and manganese salts are ores (such as nickel-cobalt ore, copper-cobalt ore, arsenic-cobalt ore, pyrolusite, and pyrolusite), battery recycling, and laterite nickel ore. Extracting nickel, cobalt, and manganese from battery recycling involves the separation of nickel, cobalt, and manganese from other metals (calcium, magnesium, lithium, etc.). Extracting nickel from laterite nickel ore involves the separation from aluminum, calcium, and magnesium. Extracting manganese from manganese-magnesium waste involves the separation of manganese from magnesium. Achieving the separation of one or more metal ions (nickel, cobalt, and manganese) from impurity ions such as calcium, magnesium, lithium, aluminum, and sodium is not only a core bottleneck in industrial production but also a current hot topic and challenge in the field of efficient recycling of secondary resources.

[0004] Existing methods for recovering nickel, cobalt, and manganese include: (1) Selective precipitation-organic solvent extraction. Manganese is precipitated by manganese hydroxide, and Ni and Co are extracted by P507 to achieve simultaneous recovery of nickel, cobalt, and manganese. However, this method has problems such as a variety of solvents, long cycle, low product purity, and the generation of a large amount of saline wastewater. (2) Co-precipitation. Ni, Co, and Mn are co-precipitated by hydroxide, carbonate, and oxalate, but this method has high requirements for equipment and extremely high investment costs. (3) Partial co-extraction system. For example, D2EHPA and Versatic 10 co-extract nickel and cobalt system, but Versatic 10 requires gradual extraction of nickel, cobalt, and manganese. (4) Ionic liquid internal co-extraction can achieve simultaneous recovery of nickel and cobalt, but the raw materials are not easy to obtain, are expensive, and the solution viscosity is not easy to control. Methods for recovering manganese from manganese and magnesium solutions: (1) Chemical precipitation method: fluoride precipitation to remove magnesium, but fluoride is expensive and residual fluoride ions will corrode the equipment and cause equipment damage. (2) The separation coefficient of P204 extractant for manganese and magnesium is low, and multi-stage countercurrent extraction is required to achieve separation of manganese and magnesium. (3) Evaporation crystallization method: magnesium sulfate crystallization removes magnesium, but it has high energy consumption and the crystals contain a large amount of manganese. Summary of the Invention

[0005] To address the problems of existing technologies, this invention provides an imidazole derivative-organophosphate combined extractant and its application in nickel-cobalt-manganese extraction. This solvent extraction system exhibits high reactivity and high extraction selectivity, with low alkali consumption and low energy consumption during extraction. The extractant structure is stable, and emulsification and other problems do not occur. It can extract and recover one or more of the metal ions (nickel, cobalt, and manganese) from aqueous solutions containing these metal ions, while simultaneously separating them from impurity ions (calcium, magnesium, lithium, sodium, potassium, etc.).

[0006] The primary objective of this invention is to provide an imidazole derivative-organophosphate combined extractant, designed for the efficient extraction of target elements.

[0007] The second objective of this invention is to provide a method for efficiently extracting nickel, cobalt, and manganese from an aqueous solution containing one or more metal ions of nickel, cobalt, and manganese using the aforementioned imidazole derivative-organophosphate combined extractant, while simultaneously separating nickel, cobalt, and manganese from impurity ions (calcium, magnesium, lithium, sodium, potassium, etc.).

[0008] An imidazole derivative-organophosphate combined extractant, wherein the imidazole derivative-organophosphate combined extractant and a diluent constitute a co-extracting organic phase, wherein the imidazole derivative is one or more having a structure of formula A1 or AII, and the organophosphate extractant is one or more having a structure of formula B.

[0009] Furthermore, the molar ratio of the imidazole derivative to the organophosphate is 10:1 to 1:10.

[0010] Furthermore, the organic phosphoric acid can be saponified using one or more of the following: NaOH, NaHCO3, Na2CO3, KOH, KHCO3, K2CO3, ammonia, MgO, Mg(OH)2, Mg(HCO3)2, MgCO3, CaO, and Ca(OH)2. Furthermore, the diluent is kerosene, sulfonated kerosene, aviation kerosene, or C8-C4 kerosene. 16 One or more of the following: higher alcohols, ketones, ethers, esters, Escaid 110, and aromatic diluents.

[0011] Furthermore, the volume concentration of the imidazole derivative-organophosphate combined extractant is 5% to 60%; preferably 20% to 45%.

[0012] The method of using the imidazole derivative-organophosphate combined extractant as described above is characterized in that the co-extracting organic phase is used to extract a solution containing nickel, cobalt, and manganese to obtain an organic phase loaded with nickel, cobalt, and manganese.

[0013] Furthermore, the nickel-cobalt-manganese-containing solution is an aqueous solution containing one or more metal ions selected from nickel, cobalt, and manganese, with a pH < 7 in the aqueous phase and SO42-containing anions. 2- Cl - Or NO3 - It may contain one or more of the following, and may also contain one or more of the following impurity ions: calcium ions, magnesium ions, lithium ions, sodium ions, and potassium ions.

[0014] Furthermore, the co-extracted organic phase is mixed and contacted with a feed solution containing nickel, cobalt, and manganese, with an A / O ratio of 10:1 to 1:10; the feed solution temperature is 0 to 60 °C; and the extraction method is single-stage, multi-stage cross-flow, or multi-stage countercurrent extraction.

[0015] Further, the organic phase supported on nickel, cobalt, and manganese is an organic phase supported on one or more metal ions selected from nickel, cobalt, and manganese; the organic phase supported on nickel, cobalt, and manganese is back-extracted using an acid solution to obtain a back-extraction solution containing nickel, cobalt, and manganese; the acid solution is H... + An aqueous solution containing one or more of sulfuric acid, hydrochloric acid, and nitric acid with a concentration greater than 0.1 mol / L; the O / A ratio for back-extraction is 1:1 to 15:1, preferably 1:1 to 8:1; the temperature of the back-extraction solution is 0 to 60 ℃; the back-extraction method is single-stage, multi-stage cross-flow, or multi-stage countercurrent back-extraction.

[0016] Furthermore, the acid solution can be an acid leaching solution for a ternary cathode material of a lithium battery, or an acid leaching solution for nickel-cobalt laterite nickel ore, or a battery acid leaching solution containing manganese and magnesium.

[0017] The solvent extraction system of the imidazole derivative-organophosphate combined extractant of the present invention can achieve a single-stage extraction rate of over 95% for nickel, over 90% for cobalt, and over 80% for manganese. The extraction rates of impurity ions such as calcium, magnesium, lithium, and sodium are <5%, <4%, <5%, and <2%, respectively. The purity of nickel, cobalt, and manganese can reach over 99%.

[0018] The imidazole derivative-organophosphate combined extractant of the present invention is suitable for extracting one or more nickel, cobalt, and manganese metals from various nickel, cobalt, and manganese-containing solutions, such as battery leachate, ore leachate, nickel-cobalt-manganese-containing wastewater, and alloy waste leachate containing one or more nickel, cobalt, and manganese metal ions.

[0019] Beneficial effects

[0020] Compared with existing technologies, the solvent extraction system of this invention is a synergistic extraction system based on a mixture of imidazole derivatives and organophosphates. Its selectivity for nickel, cobalt, and manganese is far higher than that for impurity metal ions such as calcium, magnesium, lithium, sodium, and potassium. It can efficiently separate nickel, cobalt, and manganese from solutions containing calcium, magnesium, lithium, sodium, and potassium. Furthermore, the extraction system exhibits high stability, no emulsification or third-phase formation, high efficiency, low cost, and environmental friendliness. This solvent extraction system can be advantageously applied to extract one or more nickel, cobalt, and manganese metal ions from various nickel-cobalt-manganese solutions. Its selectivity for nickel, cobalt, and manganese is particularly pronounced when nickel, cobalt, and manganese coexist with calcium, magnesium, and lithium in lithium batteries. Using this solvent extraction system to extract and recover one or more nickel, cobalt, and manganese from mixed solutions containing nickel, cobalt, manganese, calcium, magnesium, and lithium, and weakly acidic nickel-cobalt-manganese solutions, the purification and concentration of nickel, cobalt, and manganese can be achieved simultaneously, shortening the process flow and recovery cycle, and improving the recovery rate. This solvent extraction system is of great significance for the efficient utilization of nickel, cobalt, and manganese resources. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the process of using the solvent extraction system of the present invention for co-extraction and back-extraction of nickel, cobalt, manganese, calcium, magnesium and lithium solutions. Detailed Implementation

[0022] The following embodiments are provided to illustrate the present invention in more detail, but the present invention is not limited to these embodiments in any way. Within the scope of the technical concept of the present invention, those skilled in the art can make various modifications.

[0023] Example 1

[0024] The nickel-cobalt-manganese solution to be treated is NCM battery powder. After high-temperature acid leaching, the resulting solution contains 3 g / L nickel, 1.02 g / L cobalt, 1.5 g / L manganese, 0.3 g / L calcium, 1.1 g / L magnesium, and 2.4 g / L lithium.

[0025] An organic phase was prepared using 6 vol% N-octylimidazole, 3 vol% Cyanex 272 (bis(2,4,4-trimethylpentyl)phosphonic acid), and 91 vol% No. 260 solvent oil. NaOH solution was added to achieve a saponification degree of 45%. The organic phase was then subjected to single-stage extraction with the aqueous phase at a 1:1 volume ratio in a high-speed shaker to obtain a nickel-cobalt-manganese-loaded organic phase. The single-stage extraction rates for nickel, cobalt, and manganese were >95%, >90%, and >80%, respectively. The single-stage extraction rates for calcium, magnesium, and lithium were <2%, <3%, and <5%, respectively. The nickel-cobalt-manganese-loaded organic phase was then subjected to single-stage back-extraction with 2 mol / L sulfuric acid at a 1:1 volume ratio. The back-extraction rates for nickel, cobalt, and manganese were >98%, >95%, and >95%, respectively. The back-extracted organic phase was returned to the extraction section for recycling.

[0026] Example 2

[0027] The nickel-cobalt-manganese solution to be treated was laterite nickel ore. After high pressure treatment, a leachate was obtained. The resulting solution contained 1.90 g / L nickel, 0.07 g / L cobalt, 1.10 g / L manganese, 0.92 g / L magnesium, 0.04 g / L calcium, and trace amounts of iron and aluminum.

[0028] An organic phase was prepared using 4 vol% 1-(1-octyl-1H-imidazol-2-yl)acetone, 2 vol% P204 (diisooctyl phosphate), 64 vol% No. 260 solvent oil, and 30 vol% isooctanol. NaOH solution was added to the organic phase, resulting in a saponification degree of 50%. The organic phase and aqueous phase were subjected to single-stage extraction in a high-speed shaker at a 2:1 volume ratio to obtain a nickel-cobalt-manganese-loaded organic phase. The single-stage extraction rates for nickel, cobalt, and manganese were >96%, >92%, and >86%, respectively. The extraction rates for calcium and magnesium were <4% and <2%, respectively. The nickel-cobalt-manganese-loaded organic phase was then subjected to single-stage back-extraction with 2 mol / L sulfuric acid at a 1:2 volume ratio, resulting in nickel-cobalt-manganese back-extraction rates >96%, >95%, and >95%, respectively.

[0029] Example 3

[0030] The nickel-cobalt-manganese solution to be treated was alloy waste. After high-temperature acid leaching, it yielded 0.12 g / L nickel, 0.15 g / L cobalt, 0.22 g / L manganese, 20 g / L sodium, 0.12 g / L calcium, and 0.05 g / L magnesium. 1-Octyl-1H-imidazole-2-carbaldehyde

[0031] An organic phase was prepared using 3 vol% 1-octyl-1H-imidazolium-2-carboxaldehyde, 3 vol% Cyanex 272 (bis(2,4,4-trimethylpentyl)phosphonic acid), and 94 vol% solvent oil No. 260. NaOH solution was added to the organic phase, resulting in a saponification degree of 50%. The organic phase and aqueous phase were subjected to single-stage extraction in a high-speed shaker at a volume ratio of 5:1 to obtain a nickel-cobalt-manganese-loaded organic phase. The single-stage extraction rates for nickel, cobalt, and manganese were >95%, >95%, and >90%, respectively. The single-stage extraction rates for sodium, calcium, and magnesium were <2%, <3%, and <5%, respectively. The nickel-cobalt-manganese-loaded organic phase was then subjected to single-stage back-extraction with 2 mol / L sulfuric acid at a volume ratio of 1:5, resulting in nickel-cobalt-manganese back-extraction rates >95%, >90%, and >90%, respectively.

[0032] Example 4

[0033] The manganese-magnesium solution to be treated is a magnesium slag solution obtained from electrolytic manganese. After treatment, it yields 5 g / L manganese and 5 g / L magnesium.

[0034] An organic phase was prepared using 5 vol% 4-methyl-1-octyl-1H-imidazolium, 2 vol% P507 (2-ethylhexylphosphonic acid mono-2-ethylhexyl ester), and 93 vol% No. 260 solvent oil. NaOH solution was added to the organic phase, resulting in a saponification degree of 50%. The organic phase and aqueous phase were subjected to single-stage extraction in a high-speed shaker at a 1:1 volume ratio to obtain a manganese-loaded organic phase. The single-stage extraction rates for manganese were >97% and for magnesium were <5%. The manganese-loaded organic phase was then subjected to single-stage back-extraction with 2 mol / L sulfuric acid at a 1:5 volume ratio, resulting in manganese back-extraction rates >95%.

Claims

1. An imidazole derivative-organophosphate combined extractant, characterized in that, The imidazole derivative-organophosphate combined extractant and diluent constitute a co-extracting organic phase, wherein the imidazole derivative is one or more having a structure of formula AI or formula AII, and the organophosphate extractant is one or more having a structure of formula B. ； Wherein R1 is a C6-16 alkyl group, and R2, R3, and R4 are H, aldehyde, C1-6 alkyl, alkoxy, or acyl groups. R2, R3, and R4 can be the same or different. 。 2. The imidazole derivative-organophosphate combined extractant according to claim 1, characterized in that, The molar ratio of the imidazole derivative to the organophosphate is 10:1 to 1:

10.

3. The imidazole derivative-organophosphate combined extractant according to claim 1, characterized in that, The organic phosphoric acid can be saponified using one or more of the following: NaOH, NaHCO3, Na2CO3, KOH, KHCO3, K2CO3, ammonia, MgO, Mg(OH)2, Mg(HCO3)2, MgCO3, CaO, and Ca(OH)2.

4. The imidazole derivative-organophosphate combined extractant according to claim 1, characterized in that, The diluent is kerosene, sulfonated kerosene, aviation kerosene, C8-C... 16 One or more of the following: higher alcohols, ketones, ethers, esters, Escaid 110, and aromatic diluents.

5. The imidazole derivative-organophosphate combined extractant according to claim 1, characterized in that, The volume concentration of the imidazole derivative-organophosphate combined extractant is 5% to 60%.

6. A method for applying the imidazole derivative-organophosphate combined extractant according to claim 1, characterized in that, The nickel-cobalt-manganese mixture was extracted from a solution containing nickel, cobalt, and manganese using the co-extraction organic phase.

7. The method of applying the imidazole derivative-organophosphate combined extractant according to claim 6, characterized in that, The nickel-cobalt-manganese-containing solution is an aqueous solution containing one or more metal ions selected from nickel, cobalt, and manganese, with a pH < 7 in the aqueous phase and SO42-containing anions. 2- Cl - Or NO3 - It may contain one or more of the following, and may also contain one or more of the following impurity ions: calcium ions, magnesium ions, lithium ions, sodium ions, and potassium ions.

8. The method of applying the imidazole derivative-organophosphate combined extractant according to claim 6, characterized in that, The co-extracted organic phase is mixed and contacted with a nickel-cobalt-manganese feed solution, with an A / O ratio of 10:1 to 1:10; the feed solution temperature is 0 to 60 °C; and the extraction method is single-stage, multi-stage cross-flow, or multi-stage countercurrent extraction.

9. The method of applying the imidazole derivative-organophosphate combined extractant according to claim 6, characterized in that, The nickel-cobalt-manganese-supported organic phase is an organic phase supported with one or more metal ions selected from nickel, cobalt, and manganese; the nickel-cobalt-manganese-supported organic phase is back-extracted using an acid solution to obtain a back-extraction solution containing nickel, cobalt, and manganese; the acid solution is H2O. + An aqueous solution containing one or more of sulfuric acid, hydrochloric acid, and nitric acid with a concentration greater than 0.1 mol / L; the O / A ratio for back-extraction is 1:1 to 15:1, and the temperature of the back-extraction solution is 0 to 60 ℃; the back-extraction method is single-stage, multi-stage cross-flow, or multi-stage countercurrent back-extraction.

10. The method of applying the imidazole derivative-organophosphate combined extractant according to claim 9, characterized in that, The acid solution can be further described as an acid leaching solution for ternary cathode materials of lithium batteries, or an acid leaching solution for nickel-cobalt laterite nickel ore, or a battery acid leaching solution containing manganese and magnesium.

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