Method for selectively extracting and separating calcium from manganese-containing solution

Abstract

The invention discloses a method for selectively extracting and separating calcium from a manganese-containing solution, which comprises the following steps of: contacting an organic phase containing a synergistic extractant with a mixed aqueous solution containing calcium and manganese for extraction to ensure that calcium enters the organic phase and manganese ions remain in the aqueous phase to obtain a manganese salt solution and a calcium-loaded organic phase; washing the calcium-loaded organic phase, performing back extraction with inorganic acid to obtain a calcium salt solution, realizing efficient separation of calcium ions and manganese ions, performing saponification treatment on the organic phase after back extraction, and returning to extraction. The method has the characteristics of good calcium-manganese separation effect, short flow, simplicity in operation, low cost and easiness in industrial realization.

Description

Technical Field

[0001] The present invention relates to the field of separation and purification of metal ions, and particularly to a method for selectively separating calcium from a manganese-containing solution. Background Art

[0002] Manganese sulfate is a very important basic manganese salt. In recent years, due to the development of cathode materials such as lithium manganese oxide and ternary lithium, the application of manganese sulfate in the battery industry has become increasingly widespread. Battery-grade manganese sulfate has strict requirements for the content of various impurities. Impurity calcium is one of the important elements that need to be strictly controlled. However, the deep removal of trace calcium in manganese sulfate solution is still a technical problem in the preparation process of high-purity manganese compounds.

[0003] At present, the fluoride precipitation method and the manganese sulfate recrystallization method are widely used in industry for deep calcium removal from manganese-containing solutions. The fluoride precipitation method utilizes the difference in the solubility product of manganese fluoride being relatively large while that of calcium fluoride being low. After adjusting the pH of the feed liquid, fluoride salts are added to precipitate calcium, achieving deep separation of manganese and calcium. However, this method introduces a new impurity ion F-, and an additional step for deep fluoride removal is required. Otherwise, it will cause problems such as product quality, equipment corrosion, and environmental pollution. The recrystallization method has problems of high energy consumption and low direct manganese recovery rate.

[0004] The solvent extraction method has good purification effect and has advantages such as low energy consumption, short process, high efficiency, and easy automation control. It is considered the most promising method for calcium-manganese separation. Cyanex272 (Experimental study on the extraction and separation of manganese, magnesium, and calcium by Cyanex272 [J]. Hydrometallurgy, 2020, 39: 390-394.) and the synergistic extractant of organic phosphoric acid / pyridine acid ester (Chinese Patent CN109097599) have both achieved preferential extraction of manganese from manganese sulfate solutions containing calcium and magnesium impurities to realize deep separation of manganese from calcium and magnesium. However, the above methods all preferentially extract the main element manganese to achieve deep removal of trace impurity calcium. The amount of acid-base reagents used in the extraction process is large, the amount of waste salts generated is large, and the cost is relatively high. In comparison, preferentially extracting trace calcium from a large amount of manganese has more cost advantages. Among the commonly used extractants, P204 extracts calcium prior to manganese and can, to a certain extent, achieve preferential extraction of calcium from manganese salt solutions. However, the Ca / Mn separation coefficient is not high. It is not only difficult to achieve deep calcium removal from high-concentration manganese solutions, but also the co-extraction loss of manganese is relatively large, making it difficult to meet the production requirements of battery-grade manganese sulfate. Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies of the existing methods for deep calcium removal from manganese-containing solutions and provide a method for selectively extracting and deeply removing calcium from manganese-containing solutions.

[0006] To solve the problem of the unsatisfactory extraction separation coefficient of calcium and manganese, the present invention proposes the following solutions through research:

[0007] A method for selectively extracting and separating calcium from a manganese-containing solution, which involves mixing an aqueous phase to be separated containing calcium ions and manganese ions with an organic phase containing a combined extractant (also referred to as a synergistic extractant in the present invention) for extraction to obtain an organic phase with negative calcium and a raffinate rich in manganese.

[0008] The combined extractant described above includes Compound 1 and Compound 2; among them, Compound 1 is at least one compound having the structural formula of Formula 1; Compound 2 is at least one compound having the structural formula of Formula 2;

[0009] Formula 1 is:

[0010]

[0011] Formula 2 is:

[0012]

[0013] The R1 and R2 described above are independently alkoxy groups with 6 - 12 carbon atoms; the R3 is an alkyl group with 1 - 4 carbon atoms, and the R4 and R5 are independently alkoxy groups with 6 - 10 carbon atoms; M is one or more mixtures of hydrogen ions, ammonium ions, alkali metal ions, manganese ions, nickel ions, and cobalt ions;

[0014] Regarding the selectivity problem of calcium and manganese extraction, through research, the present invention has found that when using only Compound 1, the selective separation effect of calcium and manganese is not ideal. When using only Compound 2, it basically does not have the extraction performance for calcium and manganese. However, when the two are combined, a synergistic effect can be produced, which can effectively and positively synergistically improve the extraction rate of calcium and anti - synergistically inhibit the concomitant extraction of manganese, thereby significantly improving the separation selectivity of calcium and manganese and increasing the extraction separation coefficient of the two.

[0015] In the present invention, the aqueous phase to be separated can be a solution containing calcium and manganese from any source, and there is no requirement for the concentrations of calcium and manganese therein. However, for the sake of treatment efficiency and economy, the concentration of calcium is 0.05 - 0.8 g / L, and the concentration of manganese is 2.0 - 150.0 g / L. It should be noted that the aqueous phase to be separated may also contain one or more metal ions such as Ni, Co, Zn, Cu, and Mg.

[0016] In the present invention, the combination of Compound 1 and Compound 2 is the key to synergistically improving the extraction separation selectivity of calcium and manganese and increasing the separation coefficient.

[0017] The present invention has found through research that on the basis of the combination and synergy of Compound 1 and Compound 2 described above, further controlling the ratio of the two and the aqueous phase equilibrium pH during the extraction process can further synergistically improve the separation selectivity of calcium and manganese.

[0018] Preferably, the molar ratio of Compound 1 to Compound 2 is 1:1 - 1:5.

[0019] In the present invention, the concentration of Compound 1 in the organic phase is 0.1 to 0.8 mol / L; preferably 0.2 to 0.6 mol / L.

[0020] In the present invention, the organic phase further contains a diluent;

[0021] Preferably, the diluent is at least one of sulfonated kerosene, Solvent Oil No. 260, Escaid 110, and higher alcohols with 8 to 13 carbon atoms;

[0022] In the present invention, the equilibrium pH of the aqueous phase in the extraction process is 1.5 - 5.0.

[0023] In the present invention, the equilibrium pH of the extraction process can be controlled by controlling the pH value of the aqueous phase to be separated, the saponification of the organic phase, and the saponification rate.

[0024] In the present invention, the organic phase can be unsaponified or saponified. The alkali solution used in the saponification process is at least one of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and ammonia water; the concentration of the alkali solution is 1.0 to 10.0 mol / L.

[0025] In the present invention, when the organic phase is a saponified organic phase, its saponification rate is greater than 0%, preferably 10 - 80; further optimized to 30 - 60%.

[0026] In the present invention, to control the content of alkali metals or ammonium in the manganese sulfate solution, the saponified organic phase can be further subjected to trans-saponification treatment with a manganese salt solution, a nickel salt solution, a cobalt salt solution, or a mixed salt solution of the three or a mixed salt solution of two of them.

[0027] Preferably, the pH value of the aqueous phase to be separated is 1.0 - 7.0, preferably 2.0 - 5.0.

[0028] In the present invention, the extraction operation can be realized based on existing means and equipment. For example, the number of extraction stages in the extraction process is greater than or equal to 1 stage; preferably 2 - 10 stages; preferably, when the number of extraction stages is greater than or equal to 2 stages, the extraction method is countercurrent extraction; preferably, during the extraction process, the volume flow ratio of the organic phase to the aqueous phase feed liquid is 1 / 10 - 10 / 1.

[0029] In the present invention, means can be adopted to recover manganese from the loaded organic phase, for example, washing the loaded organic phase with a detergent.

[0030] Preferably, the detergent is an aqueous solution of at least one inorganic acid such as sulfuric acid, nitric acid, and hydrochloric acid. Preferably, the concentration of the detergent is 0.1 - 5 mol / L. In the present invention, the number of washing stages in the washing process is greater than or equal to 1 stage; preferably 2 - 5 stages.

[0031] Preferably, when the number of washing stages is greater than or equal to 2, the washing method is preferably countercurrent washing; preferably, during the washing process, the volume flow ratio of the organic phase to the aqueous phase feed liquid is 1 / 1 to 30 / 1.

[0032] It should be noted that

[0033] The loaded organic phase is recycled and regenerated. For example, a stripping agent is used to strip the washed organic phase to obtain a blank organic phase;

[0034] Preferably, the stripping agent is an aqueous solution of at least one inorganic acid such as hydrochloric acid, nitric acid, or sulfuric acid, and further preferably an aqueous hydrochloric acid solution; preferably, the concentration of the stripping agent is 0.1 to 5 mol / L; further preferably 0.1 to 3.0 M. In the present invention, the number of stripping stages in the stripping process is greater than or equal to 1; preferably 2 to 10.

[0035] Preferably, when the number of stripping stages is greater than or equal to 2, the stripping method is preferably countercurrent stripping; preferably, during the stripping process, the volume flow ratio of the organic phase to the aqueous phase feed liquid is 1 / 1 to 15 / 1.

[0036] The present invention includes the following steps: The first step is extraction: The organic phase containing the combined extractant is contacted with the mixed feed liquid containing calcium and manganese ions for extraction. Calcium is preferentially extracted into the organic phase to obtain a calcium-loaded organic phase and an aqueous manganese salt solution, realizing the separation of calcium and manganese. The second step is washing: The calcium-loaded organic phase obtained in the first step is contacted with a detergent for washing to elute the co-extracted and entrained manganese in the loaded organic phase to obtain a washed organic phase and a washing solution. The third step is stripping: The washed organic phase obtained in the second step is contacted with a stripping agent for stripping to obtain a post-stripping organic phase and a calcium-rich stripping solution. The post-stripping organic phase is directly or saponified and then returned to the first step of extraction for repeated use.

[0037] Compared with the prior art, the beneficial effects brought by the technical solution of the present invention are:

[0038] The present invention uses a new synergistic extractant to selectively extract calcium preferentially from a manganese-containing solution, deeply removing impurity calcium in the manganese-containing solution, and is particularly suitable for deeply removing low-concentration calcium from a high-manganese and low-calcium solution; the present invention has a short process, high calcium removal depth, low manganese loss rate, good calcium-manganese separation efficiency, low chemical reagent consumption, low cost, and is easy to realize industrialization. Specific Embodiments

[0039] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0040] In the embodiment, the distribution ratio D, the separation factor β, the extraction rate E(%), and the calcium removal rate Y(%) are calculated according to formulas (1) to (4) respectively:

[0041] D = C MO / C MR (1)

[0042] β Ca / Mn = D Ca / D Mn (2)

[0043] E = (C F ·V F - C R ·V R ) / (C F ·V F ) × 100% (3)

[0044] Y = (C CaF / C MnF - C CaR / C MnR ) / (C CaF / (C MnF ) × 100% (4)

[0045] In formula (1), C MO , C MR respectively represent the concentrations (g / L) of metal ion M in the loaded organic phase and the raffinate; in formula (2), β Ca / Mn represents the separation factor of Ca and Mn, and D Ca , D Mn respectively represent the distribution ratios of Ca and Mn; in formula (3), C F , C R respectively represent the concentrations (g / L) of metal ions in the feed solution and the raffinate, and V F , V R respectively represent the volumes (L) of the feed solution and the raffinate; in formula (4), C CaF , C MnF respectively represent the concentrations (g / L) of Ca and Mn ions in the feed solution, and C CaR , C MnR respectively represent the concentrations (g / L) of Ca and Mn ions in the raffinate.

[0046] Example 1

[0047] Aqueous phase feed solution to be separated: a manganese sulfate solution containing calcium, where Ca 2+ is 0.256 g / L, Mn 2+ is 50.36 g / L, and the pH value is 4.0.

[0048] Organic phase: Three organic phases with different compositions numbered 1, 2, and 3 were prepared. The diluent in the organic phase was sulfonated kerosene. Organic phase No. 1 was a sulfonated kerosene solution of 0.5 mol / L phosphoric acid extractant P204 [bis(2-ethylhexyl)phosphoric acid], organic phase No. 2 was a sulfonated kerosene solution of 1.0 mol / L P350 [bis(1-methylheptyl)methylphosphonate], and organic phase No. 3 was a sulfonated kerosene solution of 0.5 mol / L P204 + 1.0 mol / L P350. The above three organic phases were respectively saponified with sodium hydroxide solution, and the saponification rate of the organic phase was 40%.

[0049] The above three organic phases were respectively subjected to single-stage extraction with the aqueous phase feed solution under the condition that the phase ratio (volume ratio of the organic phase to the aqueous phase) was 1 / 1. The extraction equilibrium time was 10 min, and the temperature was 20 °C. The experimental results are shown in Table 1.

[0050] Table 1 Extraction results

[0051]

[0052]

[0053] As can be seen from Table 1, when using P204 alone for extraction, the extraction rates of calcium and manganese were 24.45% and 10.64% respectively, and the separation factor β Ca / Mn was 2.72; when using P350 alone for extraction, calcium and manganese were hardly extracted, and their extraction rates were both less than 1%; when using the mixed organic phase of P204 and P350 for extraction, the extraction rate of calcium reached 62.98%, and the extraction rate of manganese was only 6.69%, and the separation factor β Ca / Mn reached 23.73. It showed an obvious positive synergistic effect on calcium and an obvious negative synergistic effect on manganese. Compared with the P204 extraction system, the P204-P350 mixed extraction system could significantly improve the calcium-manganese separation effect.

[0054] Example 2

[0055] The aqueous phase feed solution to be separated was the same as that in Example 1.

[0056] The organic phase was a No. 260 solvent oil solution of 0.5 mol / L P215 [bis(1-methylheptyl)phosphoric acid] + 1.0 mol / L P277 [diisooctyl isopropylphosphonate], and was saponified with ammonia water. By controlling different saponification rates, the equilibrium pH value during the extraction process was controlled. 1 mol / L ammonia water was used as the saponifying agent to saponify the organic phase, and the saponification rates were 0%, 20%, 40%, 60%, 80%, and 100% respectively.

[0057] The organic phases with different saponification rates were respectively subjected to single-stage extraction with the feed liquid under the condition that the phase ratio (volume ratio of the organic phase to the aqueous phase) was 1 / 1. The extraction equilibrium time was 10 min and the temperature was 25 °C. The experimental results are shown in Table 2.

[0058] Table 2 Results of Extraction Tests

[0059] Saponification rate of organic phase 0 20 40 60 80 100 Equilibrium pH value of aqueous phase 1.53 2.25 2.78 3.42 3.91 4.57 Calcium extraction rate (%) 18.75 37.07 70.75 72.3 73.13 70.21 Manganese extraction rate (%) 2.46 3.84 6.46 15.2 21.52 23.56 Calcium distribution ratio 0.23 0.59 2.42 2.61 2.72 2.36 Manganese distribution ratio 0.025 0.040 0.069 0.179 0.274 0.308 <![CDATA[β Ca / Mn > 9.15 14.75 35.02 14.56 9.93 7.65

[0060] As can be seen from Table 2, during the extraction process, as the saponification rate increases, the equilibrium pH value of the aqueous phase continuously rises, the manganese extraction rate increases accordingly, but the calcium extraction rate first rises and then falls, and the calcium-manganese separation coefficient also first rises and then falls. Thus, it can be seen that under this extraction system, the equilibrium pH value of the extraction aqueous phase has an obvious influence on the calcium-manganese separation effect. When the equilibrium pH value of the extraction aqueous phase is controlled in the range of 2-4, β Ca / Mn > 10.

[0061] Example 3

[0062] Aqueous phase feed liquid to be separated: Ca 0.493 g / L, Mn 127.65 g / L, pH value 5.0.

[0063] Organic phase: 0.5 mol / L P204 + 0.75 mol / L P227 + Escaid110. The organic phase was saponified with 5 mol / L NaOH solution (saponification rate was 30%), and the saponified organic phase was then subjected to trans-saponification treatment with manganese sulfate solution.

[0064] Detergent: 1.0 mol / L sulfuric acid solution.

[0065] Stripping agent: 3.0 mol / L hydrochloric acid solution.

[0066] Operation: The aqueous phase feed liquid was subjected to multi-stage countercurrent extraction with the saponified organic phase. The loaded organic phase obtained from the extraction was subjected to multi-stage countercurrent washing with the detergent. The aqueous phase generated from the washing was incorporated into the extraction feed liquid (also known as fractional extraction); the washed organic phase was subjected to multi-stage countercurrent stripping with the stripping agent. After stripping, the organic phase was saponified with NaOH solution and then subjected to trans-saponification treatment with manganese sulfate solution and then returned to the extraction for recycling.

[0067] Among them, there were 7 stages in the extraction section, 3 stages in the washing section, and 3 stages in the stripping section. The volume flow ratio of the organic phase: aqueous phase: detergent: stripping agent was: 30∶10∶1∶2.

[0068] Effect: After the above extraction-washing-stripping operation reached a stable state, the following results were obtained: The raffinate contained Ca 0.012 g / L and Mn 130.23 g / L; the stripping solution contained Ca 2.18 g / L and Mn 19.17 g / L. The Ca / Mn in the raffinate was only 0.92×10-4 , far lower than Ca / Mn (38.6×10 -4 ) in the extraction aqueous phase feed liquid. The removal rate Y of calcium reaches 97.61%, realizing the deep removal of calcium in the manganese sulfate solution, and the calcium content therein meets the production requirements of battery-grade manganese sulfate.

[0069] Example 4

[0070] Aqueous phase feed liquid to be separated: Ca 0.052 g / L, Mn 19.34 g / L, pH value 3.2.

[0071] Organic phase: 0.1 mol / L P204 + 0.5 mol / L P227 + Escaid110. The organic phase is saponified with 1 mol / L KOH solution (saponification rate is 40%), and the saponified organic phase is then subjected to trans-saponification treatment with manganese sulfate solution.

[0072] Detergent: 0.1 mol / L hydrochloric acid solution.

[0073] Stripping agent: 0.5 mol / L sulfuric acid solution.

[0074] Operation: The aqueous phase feed liquid and the trans-saponified organic phase are subjected to multi-stage countercurrent extraction. The loaded organic phase obtained by extraction is subjected to single-stage washing with the detergent, and the aqueous phase generated by washing is incorporated into the extraction feed liquid; the washed organic phase and the stripping agent are subjected to multi-stage countercurrent stripping, and the organic phase after stripping is saponified with KOH solution and then returned to the extraction for recycling.

[0075] Among them, there are 10 stages in the extraction section, 1 stage in the washing section, 1 stage in the stripping section, and the volume flow ratio of the organic phase: aqueous phase: detergent: stripping agent is: 15∶10∶1∶1.

[0076] Effect: After the above extraction - washing - stripping operation reaches a stable state, the following results are obtained: The raffinate contains Ca 0.002 g / L and Mn 17.14 g / L; the stripping solution contains Ca 0.45 g / L and Mn 4.84 g / L. The Ca / Mn in the raffinate is only 1.16×10 -4 , far lower than Ca / Mn (26.8×10 -4 ) in the extraction aqueous phase feed liquid. The removal rate Y of calcium reaches 95.67%, realizing the deep removal of calcium in the manganese sulfate solution.

[0077] Example 5

[0078] Aqueous phase feed liquid to be separated: Ca 0.570 g / L, Mn 14.07 g / L, Ni 106.25 g / L, Co 12.35 g / L, Zn 1.83 g / L, Cu 0.06 g / L, pH value 4.0.

[0079] Organic phase: 0.6 mol / L P204 + 0.9 mol / L P350 + Solvent oil No. 260. The organic phase is saponified with 10 mol / L ammonia aqueous solution (saponification rate is 30%).

[0080] Detergent: 1.0 mol / L sulfuric acid solution.

[0081] Stripping agent: 0.5 mol / L nitric acid solution.

[0082] Operation: The aqueous phase feed liquid and the saponified organic phase are subjected to multi-stage countercurrent extraction. The loaded organic phase obtained from extraction is subjected to single-stage washing with the detergent, and the aqueous phase generated from washing is incorporated into the extraction feed liquid; the washed organic phase and the stripping agent are subjected to multi-stage countercurrent stripping. The organic phase after stripping is saponified with ammonia aqueous solution and then returned to the extraction for recycling.

[0083] Among them, there are 4 extraction stages, 5 washing stages, and 3 stripping stages. The volume flow ratio of the organic phase : aqueous phase : detergent : stripping agent is: 30∶20∶1∶3.

[0084] Effect: After the above extraction - washing - stripping operation reaches a steady state, the following results are obtained: The raffinate contains 0.001 g / L of Ca and 13.13 g / L of Mn; the stripping solution contains 5.70 g / L of Ca and 2.82 g / L of Mn. The Ca / Mn in the raffinate is only 0.76×10 -4 , far lower than the Ca / Mn (40.51×10 -4 ) in the extraction aqueous phase feed liquid. The removal rate Y of calcium reaches 98.12%, achieving deep removal of calcium in the manganese sulfate solution, and the calcium content therein meets the production requirements of battery-grade manganese sulfate.

[0085] Example 6

[0086] Aqueous phase feed liquid to be separated: 0.416 g / L of Ca, 4.02 g / L of Mn, 1.14 g / L of Ni, 54.41 g / L of Co, 1.37 g / L of Zn, 0.06 g / L of Cu, pH value 4.0.

[0087] Organic phase: 0.1 mol / L P204 + 0.5 mol / L P350 + Solvent oil No. 260. The organic phase is saponified with 10 mol / L ammonia aqueous solution (saponification rate is 40%).

[0088] Detergent: 1.0 mol / L sulfuric acid solution.

[0089] Stripping agent: 0.5 mol / L nitric acid solution.

[0090] Operation: The aqueous feed liquid and the saponified organic phase are subjected to multi-stage countercurrent extraction. The loaded organic phase obtained from the extraction is subjected to single-stage washing with a detergent, and the aqueous phase generated from the washing is incorporated into the extraction feed liquid. The washed organic phase is subjected to multi-stage countercurrent stripping with a stripping agent. The stripped organic phase is saponified with an ammonia aqueous solution and then returned to the extraction for recycling.

[0091] Among them, there are 4 extraction stages, 5 washing stages, and 3 stripping stages. The volume flow ratio of the organic phase : aqueous phase : detergent : stripping agent is: 30∶20∶1∶3.

[0092] Effect: After the above extraction - washing - stripping operation reaches a steady state, the following results are obtained: The raffinate contains 0.001 g / L of Ca and 4.05 g / L of Mn; the stripping solution contains 5.70 g / L of Ca and 2.82 g / L of Mn. The Ca / Mn in the raffinate is only 2.46×10 -4 , far lower than the Ca / Mn (103.5×10 -4 ) in the extraction aqueous feed liquid. The removal rate Y of calcium reaches 97.62%, achieving deep removal of calcium in the manganese sulfate solution.

Claims

1. A method for selectively extracting and separating calcium from a manganese-containing solution, characterized in that, It includes the following steps: Mix the aqueous phase to be separated containing calcium ions and manganese ions with the organic phase containing the combined extractant for single-stage or multi-stage countercurrent extraction to obtain a loaded organic phase enriched with calcium and a raffinate enriched with manganese. After washing, the loaded organic phase is subjected to single-stage or multi-stage countercurrent stripping with an inorganic acid aqueous solution to obtain a stripping solution enriched with calcium. The organic phase after stripping is directly returned to extraction or returned to extraction after saponification treatment; The combined extractant includes Compound 1 and Compound 2. Among them, Compound 1 is at least one compound having the structural formula of Formula 1; Compound 2 is at least one compound having the structural formula of Formula 2; Formula 1 is: Formula 2 is: The R1 and R2 are each independently an alkoxy group with 6-12 carbon atoms; the R3 is an alkyl group with 1-4 carbon atoms, and the R4 and R5 are each independently an alkoxy group with 4-10 carbon atoms; M is one or more of hydrogen ions, ammonium ions, alkali metal ions, manganese ions, nickel ions, and cobalt ions in mixture; The molar ratio of Compound 1 to Compound 2 in the combined extractant is 1:1-5; The organic phase further contains a diluent, and the diluent is at least one of sulfonated kerosene, Solvent Oil No. 260, Escaid 110, and higher alcohols with 8-13 carbon atoms; The concentration of Compound 1 in the organic phase is 0.1-0.8 mol / L.

2. The method according to claim 1, characterized in that, The concentration of Ca in the aqueous phase to be separated is 0.05-0.8 g / L, and the concentration of Mn is 2.0-150.0 g / L.

3. The method according to claim 1, characterized in that, The number of extraction stages is 1-10, and the volume flow rate ratio of the organic phase to the aqueous phase during the extraction process is 1 / 10-10 / 1.

4. The method according to claim 1, wherein The equilibrium pH value of the aqueous phase during the extraction process is 1.5-5.

0.

5. The method according to claim 1, wherein In the single-stage or multi-stage countercurrent back-extraction using an inorganic acid aqueous solution, the inorganic acid is at least one of sulfuric acid, hydrochloric acid or nitric acid, wherein the concentration of H + is 0.1 - 5 mol / L; the number of back-extraction stages is 1 - 5, and the volume flow rate ratio of the organic phase to the aqueous phase during the back-extraction process is 1 / 1 - 15 / 1.

6. The method according to claim 1, characterized in that, Before back-extraction, the loaded organic phase is pre-washed. The washing agent is an inorganic acid aqueous solution, and the inorganic acid is at least one of sulfuric acid, hydrochloric acid or nitric acid, where H + The concentration is 0.1 - 5 mol / L; the number of washing stages is 1 - 10. When the number of washing stages is greater than or equal to 2, the washing method is countercurrent washing, and the volume flow rate ratio of the organic phase to the aqueous phase during washing is 1 / 1 - 30 / 1.

7. The method according to claim 1, characterized in that The organic phase after stripping is subjected to saponification treatment. The lye used in the saponification process is at least one of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and ammonia water; the saponification degree is 10%-100%.

8. The method according to claim 7, wherein the saponified organic phase is subjected to trans-saponification treatment with a manganese salt solution, a nickel salt solution, a cobalt salt solution, or a mixed salt solution of the three or a mixed salt solution of two of them and then returned to extraction.

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