Method for producing lithium carbonate from waste liquid containing lithium and aluminum

Abstract

Provided is a method for producing a lithium carbonate from a basic lithium- and aluminum-containing waste liquid generated during a positive electrode material production process, the method comprising the steps of: (a) filtering the waste liquid to remove metal solids; (b) injecting carbon dioxide into the waste liquid removed of the metal solids, thereby converting a lithium hydroxide into a lithium bicarbonate; (c) adding an anion exchange resin to the lithium bicarbonate-containing waste liquid to convert a lithium sulfate into a lithium hydroxide; (d) injecting carbon dioxide into the lithium hydroxide-containing waste liquid to convert the lithium hydroxide into a lithium carbonate; and (e) concentrating the lithium carbonate-containing waste liquid using an evaporator and then recovering a solid lithium carbonate.

Description

Method for producing lithium carbonate from lithium and aluminum-containing waste liquid

[0001] The present invention relates to a method for producing lithium carbonate from waste liquid containing lithium and aluminum.

[0002]

[0003] Lithium-ion secondary batteries are widely used as secondary batteries because they have excellent charge / discharge performance and high energy density, and are particularly widely utilized in small electronic products such as mobile phones and laptops.

[0004] In lithium-ion secondary batteries, the cathode accounts for more than 60% of the total weight. For this cathode, lithium cobalt oxide (LiCoO2) is used, which has excellent reversibility, a low self-discharge rate, high capacity, high energy density, and is easy to synthesize. In addition, to reduce the amount of expensive cobalt used, it is used in the form of composite oxides such as lithium nickel cobalt manganese oxide (Li(Ni, Co, Mn)O2) and lithium manganese oxide (LiMnO2), which contain Ni, Mn, etc.

[0005] Currently, our country imports and uses the entire supply of lithium carbonate, a key raw material for lithium secondary batteries. With the expected increase in demand for lithium carbonate in the future, the price of lithium carbonate is projected to skyrocket. Furthermore, considering the country's scarcity of lithium reserves and the need to prevent environmental pollution caused by heavy metals, research is being conducted on methods to recover lithium from waste liquid or spent batteries generated during the lithium-ion battery manufacturing process.

[0006] Conventionally, research has primarily focused on methods to recover lithium from solutions obtained by leaching spent batteries with acid. However, research on processes for recovering lithium compounds from waste liquid generated during the cathode material manufacturing process has been limited, making it necessary to conduct further studies in this area.

[0007]

[0008] The present invention provides a method for producing high-purity lithium carbonate by recovering lithium from waste liquid containing lithium and aluminum generated during the manufacturing process of lithium-ion battery cathode materials.

[0009]

[0010] The problems that the present invention aims to solve are not limited to the problem(s) mentioned above, and other unmentioned problems will be clearly understood by those skilled in the art from the description below.

[0011]

[0012] To achieve the above objective, the present invention provides a method for producing lithium carbonate from a basic lithium and aluminum-containing waste liquid generated during a cathode material manufacturing process, comprising: (a) a step of filtering the waste liquid to remove metal solids; (b) a step of injecting carbon dioxide into the waste liquid from which metal solids have been removed to convert lithium hydroxide into lithium bicarbonate; (c) a step of introducing an anion exchange resin into the waste liquid from which lithium bicarbonate has been generated to convert lithium sulfate into lithium hydroxide; (d) a step of injecting carbon dioxide into the waste liquid from which lithium hydroxide has been generated to convert lithium hydroxide into lithium carbonate; and (e) a step of concentrating the waste liquid from which lithium carbonate has been generated using an evaporator and then recovering solid lithium carbonate.

[0013] The above metal may be a composite oxide comprising at least one selected from the group consisting of nickel, cobalt, manganese, and combinations thereof.

[0014] Step (b) above may involve injecting carbon dioxide into the waste liquid from which the metal solids have been removed to adjust the pH of the waste liquid to pH 6.5 to 7.5.

[0015] The above step (b) may include injecting carbon dioxide into the waste liquid from which the metal solids have been removed to precipitate the aluminum remaining in the waste liquid.

[0016] Step (c) above may involve adding an anion exchange resin to the waste liquid in which lithium bicarbonate is generated to adjust the pH of the waste liquid to pH 11 to 13.

[0017] Step (c) above may involve adding 10 to 45 parts by weight of the anion exchange resin to 100 parts by weight of the waste liquid in which lithium bicarbonate is generated.

[0018] In step (c) above, the anion exchange resin may include at least one selected from the group consisting of polystyrene-based resins substituted with quaternary ammonium, acrylic-based resins, and combinations thereof.

[0019] The above anion exchange resin may include at least one selected from the group consisting of TMA (Trimethylamine), DMEA (Dimethylethanolamine), MAN210K (Samyang Corporation), M800KR (LEWATIT), SA8800N (SUNRESIN), and combinations thereof.

[0020] In step (c) above, the process may further include adding an anion exchange resin to the waste liquid in which lithium bicarbonate is generated to adjust the pH of the waste liquid to pH 11 to 13, thereby converting the lithium bicarbonate into lithium carbonate.

[0021] The above step (d) may involve injecting carbon dioxide into the waste liquid in which lithium hydroxide is generated to adjust the pH of the waste liquid to pH 9.5 to 10.

[0022] In step (e) above, the concentration may include concentrating by 5 to 10 times based on the lithium present in the basic lithium and aluminum-containing waste liquid generated during the cathode material manufacturing process.

[0023]

[0024] The present invention can efficiently recover lithium from waste liquid containing lithium and aluminum generated during the manufacturing process of lithium-ion battery cathode materials to produce high-purity lithium carbonate.

[0025]

[0026] The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description of the invention or the claims.

[0027]

[0028] FIG. 1 is a process flow diagram of a method for manufacturing lithium carbonate according to one embodiment of the present invention.

[0029] FIG. 2 is a process flow diagram of a method for manufacturing lithium carbonate according to one embodiment of the present invention.

[0030] Figure 3 is the XRD measurement result of the waste liquid containing lithium bicarbonate generated in the step of converting lithium hydroxide into lithium bicarbonate by injecting carbon dioxide according to one embodiment of the present invention.

[0031] Figure 4 is the XRD measurement result of the waste liquid containing lithium hydroxide generated in the step of converting lithium sulfate into lithium hydroxide by introducing an anion exchange resin according to one embodiment of the present invention.

[0032]

[0033] It should be noted that in the following description, only the parts necessary for understanding the embodiments of the present invention are described, and the description of other parts may be omitted to the extent that it does not detract from the gist of the present invention.

[0034] The terms and words used in the specification and claims described below should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0035] The terms used in this specification are used merely to describe exemplary embodiments and are not intended to limit the invention. The singular expression includes the plural expression unless the context clearly indicates otherwise.

[0036] In this specification, terms such as “comprising,” “comprising,” or “having” are intended to specify the existence of the implemented features, numbers, steps, components, or combinations thereof, and do not exclude the existence or addition of one or more other features, numbers, steps, components, or combinations thereof.

[0037]

[0038] A method for producing lithium carbonate from a basic lithium and aluminum-containing waste liquid generated during a cathode material manufacturing process according to the present invention comprises: (a) a step of filtering the waste liquid to remove metal solids; (b) a step of injecting carbon dioxide into the waste liquid from which metal solids have been removed to convert lithium hydroxide into lithium bicarbonate; (c) a step of introducing an anion exchange resin into the waste liquid from which lithium bicarbonate has been generated to convert lithium sulfate into lithium hydroxide; (d) a step of injecting carbon dioxide into the waste liquid from which lithium hydroxide has been generated to convert lithium hydroxide into lithium carbonate; and (e) a step of concentrating the waste liquid from which lithium carbonate has been generated using an evaporator and then recovering solid lithium carbonate (Fig. 1).

[0039]

[0040] Hereinafter, each step of the present invention will be explained in more detail.

[0041] First, prepare the waste liquid generated during the cathode material manufacturing process.

[0042] Generally, the waste liquid generated during the above cathode material manufacturing process may be basic with a pH of 12 or higher, and when the pH of the waste liquid is 12 or higher, the metal contained in the waste liquid exists in a solid state.

[0043] In one embodiment, the waste liquid may include a basic lithium and aluminum-containing waste liquid, specifically including at least one selected from the group consisting of lithium sulfate (Li2SO4), lithium hydroxide (LiOH), lithium carbonate (Li2CO3) and combinations thereof.

[0044]

[0045] Next, the prepared basic wastewater is filtered to remove metal solids (step a, S10).

[0046] The metal removed in step (a) above may be a complex oxide comprising at least one selected from the group consisting of nickel, cobalt, manganese, and combinations thereof.

[0047] The filtration in step (a) above may involve removing metal solids using a filter press.

[0048] High-purity lithium carbonate can be obtained by removing the above metal solids.

[0049]

[0050] Next, carbon dioxide is injected into the waste liquid from which the metal solids have been removed to convert lithium hydroxide into lithium bicarbonate (LiHCO3) (step b, S20).

[0051] Step (b) above can convert lithium hydroxide into lithium bicarbonate by injecting carbon dioxide into the waste liquid from which the metal solids have been removed, thereby adjusting the pH of the waste liquid to pH 6.5 to 7.5, specifically pH 7.

[0052] In one embodiment, by injecting carbon dioxide into the waste liquid, lithium hydroxide contained in the waste liquid may be converted into lithium bicarbonate through a reaction such as the following reaction scheme 1.

[0053] [Reaction Equation 1]

[0054] 2LiOH + CO2 → Li2CO3 + H2O

[0055] Li2CO₃+ CO2+ H2O → 2LiHCO3

[0056] Specifically, by injecting carbon dioxide into the waste liquid generated during the manufacturing process of the cathode material at pH 12 or higher, lithium hydroxide is converted into lithium carbonate as the pH decreases, and lithium carbonate can be converted into lithium bicarbonate at pH 7.

[0057] In step (a) above, the waste liquid from which metal solids have been removed by filtering may contain aluminum at a concentration of 10 ppm or less. The aluminum can be removed by precipitating as solids by injecting carbon dioxide into the waste liquid to adjust the pH of the waste liquid to pH 6.5 to 7.5, specifically pH 7.

[0058]

[0059] Next, an anion exchange resin is introduced into the waste liquid containing lithium bicarbonate to convert lithium sulfate into lithium hydroxide (step c, S30).

[0060] Step (c) above can convert lithium sulfate into lithium hydroxide by introducing an anion exchange resin into the waste liquid in which lithium bicarbonate is generated, thereby adjusting the pH of the waste liquid to pH 11 to 13.

[0061] That is, an anion exchange resin can be introduced to make the pH of the waste liquid in which lithium bicarbonate is generated reach pH 11 to 13.

[0062] In one embodiment, by introducing an anion exchange resin into the waste liquid in which the lithium bicarbonate is generated, the lithium sulfate contained in the waste liquid may be converted into lithium hydroxide through a reaction such as Reaction Scheme 2 below. As the lithium sulfate is converted into lithium hydroxide, the pH of the waste liquid may increase.

[0063] [Reaction Equation 2]

[0064] Li2SO4+ anion exchange resin → 2LiOH

[0065] Meanwhile, in step (c) above, the pH in the waste liquid is increased by introducing an anion exchange resin, and the process may further include converting lithium bicarbonate into lithium carbonate by adjusting the pH to 11 to 13.

[0066] In one embodiment, by introducing an anion exchange resin into the waste liquid in which the lithium bicarbonate is generated, the lithium bicarbonate contained in the waste liquid may be converted into lithium carbonate through a reaction such as the reaction scheme 3 below.

[0067] [Reaction Equation 3]

[0068] 2LiHCO3 → Li2CO3 + CO ₂ + H2O

[0069] Step (c) above may be performed simultaneously in which lithium sulfate is converted into lithium hydroxide and lithium bicarbonate is converted into lithium carbonate by introducing an anion exchange resin into the waste liquid.

[0070] In step (c) above, the anion exchange resin may be added in an amount of 10 to 45 parts by weight, 12 to 43 parts by weight, 15 to 40 parts by weight, 17 to 37 parts by weight, 20 to 33 parts by weight, 22 to 30 parts by weight, or 22 to 27 parts by weight, relative to 100 parts by weight of the waste liquid in which lithium bicarbonate is generated. When the anion exchange resin is added within the numerical ranges described above, the ion exchange reaction between lithium sulfate and the anion exchange resin can be sufficiently and effectively carried out.

[0071] The above anion exchange resin may include at least one selected from the group consisting of polystyrene-based resins substituted with quaternary ammonium, polystyrene-based resins, acrylic resins, and combinations thereof.

[0072] In one embodiment, the polystyrene-based resin substituted with quaternary ammonium may be in various forms, such as a gel type or a porous type, a homogeneous type or a non-homogeneous type.

[0073] In one embodiment, the anion exchange resin may use a strongly basic material, and specifically, may include at least one selected from the group consisting of TMA (Trimethylamine), DMEA (Dimethylethanolamine), MAN210K (Samyang Corporation), M800KR (LEWATIT), SA8800N (SUNRESIN) and combinations thereof.

[0074]

[0075] Next, carbon dioxide is injected into the waste liquid containing lithium hydroxide to convert the lithium hydroxide into lithium carbonate (step d, S40).

[0076] Step (d) above can convert lithium hydroxide into lithium carbonate by injecting carbon dioxide into the waste liquid containing lithium hydroxide produced in Step (c) above to adjust the pH of the waste liquid containing lithium hydroxide with a pH of 11 to 13 to a pH of 9.5 to 10.

[0077] In one embodiment, by injecting carbon dioxide into the waste liquid, the lithium hydroxide contained in the waste liquid may be converted into lithium carbonate through a reaction such as the following reaction scheme 4.

[0078] [Reaction Equation 4]

[0079] 2LiOH + CO2 → Li2CO3 + H2O

[0080] When carbon dioxide is injected into the waste liquid in which the above lithium hydroxide is generated, if the pH of the waste liquid is adjusted to less than 9.5, the lithium carbonate is converted into lithium bicarbonate, making it difficult to feed into the concentration facility described later.

[0081]

[0082] Next, the waste liquid containing the lithium carbonate is concentrated using an evaporator, and then the solid lithium carbonate is recovered (step e, S50).

[0083] The above concentration may be 5 to 10 times or 5 times based on the lithium present in the basic lithium and aluminum-containing waste liquid generated during the cathode material manufacturing process.

[0084] In one embodiment, when the concentration of lithium present in the waste liquid is 2000±500 ppm, it can be concentrated to 5 to 10 times or 5 times the concentration of 2000 ppm.

[0085] In one embodiment, the concentration may be achieved by concentrating and drying using a forced-circulation evaporator.

[0086] The process is carried out using the solubility of the lithium carbonate mentioned above. When the lithium carbonate introduced into the evaporator evaporates the water in the generated waste liquid, the concentration increases, and when the concentration is high, the solution becomes supersaturated, and the supersaturated lithium carbonate can be precipitated in a crystalline form.

[0087] In one embodiment, to increase the recovery rate of the solid lithium carbonate, after step (e), at least one step may be further included among (f) a step of filtering, washing, and drying the solid lithium carbonate recovered in step (e); (g) a step of injecting a washing liquid and carbon dioxide into the evaporator from which the solid lithium carbonate was recovered in step (e) to obtain a solution containing lithium bicarbonate; and (h) a step of mixing the solution containing lithium bicarbonate obtained in step (g) with the waste liquid of step (a) (Fig. 2).

[0088] First, the lithium carbonate crystallized in step (e) above is recovered, filtered, washed, and dried, and then the lithium carbonate is washed with purified water (step f).

[0089] In one embodiment, the cleaning process can be repeated three or more times.

[0090] During the above filtration and washing, water or purified water can be used to remove impurities (e.g., Na).

[0091] The lithium carbonate, after the above filtration and washing are completed, is dried for at least 3 hours using air heated with high-temperature steam. At this time, air can be injected into various parts of the equipment to ensure that the lithium carbonate is dried evenly and completely. Once drying is complete, the lithium carbonate is recovered.

[0092]

[0093] Next, a washing solution and carbon dioxide are injected into the evaporator from which solid lithium carbonate was recovered in step (e) to obtain a solution containing lithium bicarbonate (step g), and the solution containing lithium bicarbonate obtained in step (g) can be mixed with the waste liquid from step (a) (step h).

[0094] In one embodiment, after step (e), a washing solution and carbon dioxide are introduced to recover the crystallized lithium carbonate attached to the inner wall of the evaporator, thereby obtaining a solution containing lithium bicarbonate.

[0095] The above lithium carbonate can be converted into lithium bicarbonate by a reaction such as the following reaction equation 5 by introducing a washing solution (e.g., water) and carbon dioxide.

[0096] [Reaction Equation 5]

[0097] Li2CO3 + H2O + CO2 → 2LiHCO3

[0098] That is, the present invention can further increase the recovery rate of solid lithium carbonate by mixing the lithium bicarbonate solution obtained in step (g) with the waste liquid from step (a) and reusing it.

[0099] At this time, the recovered lithium carbonate can be recovered at a rate of 97% by weight or more relative to the lithium content of the waste liquid, and can be recovered as high-purity lithium carbonate of 99.5% or more.

[0100]

[0101] The above description explains the technical concept of the present invention using one embodiment, and those skilled in the art to which the present invention pertains will be able to make various modifications and variations within the scope of the essential characteristics of the present invention. Accordingly, the embodiments described in this invention are intended to explain, not limit, the technical concept of the present invention, and the scope of the technical concept of the present invention is not limited by such embodiments. The scope of protection of the present invention shall be interpreted by the claims, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of the present invention.

[0102]

[0103] <Example>

[0104] The waste liquid containing lithium and aluminum with a pH of 12, generated during the cathode material manufacturing process, was filtered using a filter press to remove NCM (Nickel Cobalt Manganese) solids. Next, carbon dioxide was injected into the waste liquid from which NCM solids had been removed to adjust the pH to 7, thereby converting the lithium hydroxide contained in the waste liquid into lithium bicarbonate. Based on 100 parts by weight of the waste liquid with a pH of 7, 25 parts by weight of MAN210K (Samyang Corporation) were injected to produce a waste liquid adjusted to a pH of 12, thereby converting the lithium sulfate contained in the waste liquid into lithium hydroxide. Next, carbon dioxide was injected a second time into the waste liquid adjusted to a pH of 12 to adjust the pH to 9.5, thereby producing lithium carbonate contained in the waste liquid. Finally, the waste liquid containing the generated lithium carbonate was concentrated using a forced-circulation evaporator to obtain crystallized solid lithium carbonate. Crystallized lithium carbonate was obtained by filtration using a filter press and washed three times with purified water. Next, the washed crystallized lithium carbonate was completely dried for 3 hours using air heated with high-temperature steam at 130°C, and solid lithium carbonate was obtained. Next, the solution containing the obtained lithium bicarbonate was mixed with waste liquid containing lithium and aluminum with a pH of 12, which is generated during the cathode material manufacturing process, and used.

[0105] A solution containing lithium bicarbonate and a waste liquid containing lithium and aluminum with a pH of 12 generated during the cathode material manufacturing process were concentrated through all the above steps, and then crystallized solid lithium carbonate was obtained.

[0106] According to the above example, when recovering lithium components in waste liquid, the recovery rate relative to the lithium content contained in the waste liquid is 97% by weight, and 99.5% of high-purity lithium carbonate can be recovered.

[0107]

[0108] <Experimental Example>

[0109] According to the above example, when recovering lithium components in waste liquid, the waste liquid before and after the addition of anion exchange resin (MAN210K (Samyang Corporation)) was concentrated and crystallized, and the changes in the major phases of the dried solid phase were measured using an X-ray diffraction analyzer, and the results are shown in FIGS. 3 (AGT-2 1002) to FIGS. 4 (AGT Sample2) and Tables 1 to 2 below.

[0110] - Analysis conditions: Cu Kα radiation, 45 kV, 200 mA, scanning range 10° ~ 80° 2θ

[0111]

[0112] Table 1 and Figure 3 below show the results before the addition of the anion exchange resin.

[0113] 2θ(°) Relative Intensity (%) Major Phases 11.3 100 Dilithium sulfate monohydrate (Li2SO4·H2O) 21.58 zabuyelite (Li2CO3) 22.86 lithium hydrxide hydrate (LiOH·H2O) 23.25 lithium sodium sulfate (LiNa(SO4))

[0114] Table 2 and Figure 4 below show the results after the addition of anion exchange resin.

[0115]

[0116] 2θ(°) Relative Intensity (%) Major Phases 21.3 100 Zabuyelite (Li2CO3) 23.48 Lithium Hydroxide Hydrate (LiOH·H2O) 30.56 Zabuyelite (Li2CO3) 3450 Lithium hydroxide (LiOH)

[0117]

[0118] Referring to Figures 3 and 4, it was confirmed that before the addition of the anion exchange resin, the phases mainly consisted of Dilithium sulfate monohydrate (Li2SO4·H2O), Zabuyelite (Li2CO3), Lithium Hydroxide Hydrate (LiOH·H2O), and Lithium sodium sulfate (LiNa(SO4)). On the other hand, after the addition of the anion exchange resin, it was confirmed that phases such as Zabuyelite (Li2CO3), Lithium Hydroxide Hydrate (LiOH·H2O), and Lithium hydroxide (LiOH) were present. From this, it was confirmed that lithium sulfate was converted into lithium hydroxide due to the addition of the anion exchange resin.

[0119]

[0120] Although the present invention has been described above with reference to embodiments, the present invention is not limited by the embodiments disclosed in this specification, and it is obvious that various modifications can be made by a person skilled in the art within the scope of the technical concept of the present invention. Furthermore, even if the effects of the configuration of the present invention were not explicitly described while describing the embodiments of the present invention above, it is natural to acknowledge that the effects predictable by said configuration should also be recognized.

Claims

1. A method for producing lithium carbonate from basic lithium and aluminum-containing waste liquid generated during the cathode material manufacturing process, (a) A step of filtering the waste liquid to remove metal solids; (b) a step of converting lithium hydroxide into lithium bicarbonate by injecting carbon dioxide into the waste liquid from which the metal solids have been removed; (c) a step of converting lithium sulfate into lithium hydroxide by introducing an anion exchange resin into the waste liquid in which lithium bicarbonate is generated; (d) a step of converting lithium hydroxide into lithium carbonate by injecting carbon dioxide into the waste liquid in which lithium hydroxide is generated; and (e) a step of concentrating the waste liquid containing lithium carbonate using an evaporator and then recovering solid lithium carbonate; comprising a method for producing lithium carbonate from lithium and aluminum-containing waste liquid.

2. In Paragraph 1, A method for producing lithium carbonate from lithium and aluminum-containing waste liquid, wherein the metal is a composite oxide comprising at least one selected from the group consisting of nickel, cobalt, manganese, and combinations thereof.

3. In Paragraph 1, The above step (b) is, A method for producing lithium carbonate from lithium and aluminum-containing waste liquid, wherein carbon dioxide is injected into the waste liquid from which the metal solids have been removed to adjust the pH of the waste liquid to pH 6.5 to 7.

5.

4. In Paragraph 1, The above step (b) is, A method for producing lithium carbonate from lithium and aluminum-containing waste liquid, comprising injecting carbon dioxide into the waste liquid from which the metal solids have been removed to precipitate the aluminum remaining in the waste liquid.

5. In Paragraph 1, The above step (c) is, A method for producing lithium carbonate from lithium and aluminum-containing waste liquid, wherein an anion exchange resin is introduced into the waste liquid in which lithium bicarbonate is generated to adjust the pH of the waste liquid to pH 11 to 13.

6. In Paragraph 1, The above step (c) is, A method for producing lithium carbonate from lithium and aluminum-containing waste liquid, wherein 10 to 45 parts by weight of the anion exchange resin are added to 100 parts by weight of the waste liquid in which lithium bicarbonate is generated.

7. In Paragraph 1, In step (c) above, A method for producing lithium carbonate from lithium and aluminum-containing waste liquid, wherein the anion exchange resin comprises at least one selected from the group consisting of polystyrene-based resins substituted with quaternary ammonium, acrylic-based resins, and combinations thereof.

8. In Paragraph 7, A method for producing lithium carbonate from lithium and aluminum-containing waste liquid, wherein the anion exchange resin comprises at least one selected from the group consisting of TMA (Trimethylamine), DMEA (Dimethylethanolamine), MAN210K (Samyang Corporation), M800KR (LEWATIT), SA8800N (SUNRESIN), and combinations thereof.

9. In Paragraph 1, In step (c) above, A method for producing lithium carbonate from lithium and aluminum-containing waste liquid, further comprising adding an anion exchange resin to the waste liquid in which lithium bicarbonate is generated to adjust the pH of the waste liquid to pH 11 to 13 to convert the lithium bicarbonate into lithium carbonate.

10. In Paragraph 1, The above step (d) is, A method for producing lithium carbonate from lithium and aluminum-containing waste liquid, wherein carbon dioxide is injected into the waste liquid in which lithium hydroxide is generated to adjust the pH of the waste liquid to 9.5 to 10.

11. In Paragraph 1, In the above (e) step, A method for producing lithium carbonate from lithium and aluminum-containing waste liquid, wherein the above concentration is 5 to 10 times based on the lithium present in the basic lithium and aluminum-containing waste liquid generated during the cathode material manufacturing process.

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