Method for producing lithium carbonate

Abstract

A method for producing lithium carbonate, according to the present invention, comprises the steps of: preparing an ore containing lithium; calcining the ore containing lithium; mixing the calcined ore containing lithium with sodium carbonate and water and performing high-temperature high-pressure leaching so as to obtain a leachate containing lithium carbonate particles; bicarbonating the leachate so as to obtain a lithium bicarbonate aqueous solution; solid-liquid separating the lithium bicarbonate aqueous solution so as to obtain a lithium bicarbonate filtrate and a residue; mixing the residue with hydrochloric acid so as to obtain sodium chloride; subjecting the sodium chloride to an electrochemical reaction; and carbonating sodium hydroxide obtained after the electrochemical reaction.

Description

Method for manufacturing lithium carbonate

[0001] The present invention relates to a method for manufacturing lithium carbonate.

[0002] The present invention claims priority based on Korean Patent Application No. 0-2024-0190892 filed on December 19, 2024, the entire contents of said application incorporated herein by reference.

[0003] Lithium compounds are used for various purposes across various industries, including secondary batteries, ceramics, glass, alloys, and pharmaceuticals. With the recent commercialization of electric vehicles and the increasing need for power storage, the demand for lithium materials is also expected to grow significantly in the future.

[0004] Meanwhile, lithium ore is easier to secure compared to salt lakes and is not constrained by climate, so mining development and lithium extraction businesses are expanding worldwide.

[0005] Conventionally, lithium carbonate was produced from lithium ore through a high-temperature, high-pressure carbonate leaching method; however, this method has the problem that the resulting residue contains NaAl(SiO3)2, making recycling impossible.

[0006] Furthermore, the alkaline precipitation method generates a significantly larger amount of residue compared to other processes. Since this residue contains Na, recycling is impossible, and it must be disposed of by landfill. This leads to increased landfill costs and presents environmental challenges.

[0007] Therefore, there is a need to develop a method for manufacturing lithium carbonate that can reduce residues generated during the process.

[0008] The present invention aims to provide a method for manufacturing lithium carbonate that can minimize the amount of auxiliary raw materials used and the generation of by-products in the process of manufacturing lithium carbonate.

[0009] The present invention provides a method for producing lithium carbonate comprising the steps of: preparing an ore containing lithium; calcining the ore containing lithium; mixing sodium carbonate and water with the calcined ore containing lithium and leaching it at high temperature and high pressure to obtain a leachate containing lithium carbonate particles; bicarbonating the leachate to obtain an aqueous lithium bicarbonate solution; separating the aqueous lithium bicarbonate solution from solid to liquid to obtain a lithium bicarbonate filtrate and a residue; mixing the residue with hydrochloric acid to obtain sodium chloride; electrochemically reacting the sodium chloride; and carbonating the sodium hydroxide obtained after the electrochemical reaction.

[0010] The method for manufacturing lithium carbonate according to the present invention has the advantage of minimizing the amount of auxiliary raw materials used and the generation of by-products.

[0011] In addition, the method for manufacturing lithium carbonate according to the present invention has the advantage of being able to recycle by-products generated during the process of manufacturing lithium carbonate.

[0012] Figure 1 is XRD analysis data of a residue obtained according to some embodiments of the present invention.

[0013] Figure 2 is XRD analysis data of a residue reacted with hydrochloric acid obtained according to some embodiments of the present invention.

[0014] Hereinafter, embodiments of the present invention will be described in detail. However, these are presented as examples and are not intended to limit the present invention, and the present invention is defined only by the scope of the claims set forth below.

[0015] In the present invention, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0016]

[0017] One aspect of the present invention relates to a method for producing lithium carbonate comprising the steps of: preparing an ore containing lithium; calcining the ore containing lithium; mixing sodium carbonate and water with the calcined ore containing lithium and leaching it at high temperature and high pressure to obtain a leachate containing lithium carbonate particles; bicarbonating the leachate to obtain an aqueous lithium bicarbonate solution; separating the aqueous lithium bicarbonate solution from solid to liquid to obtain a lithium bicarbonate filtrate and a residue; mixing the residue with hydrochloric acid to obtain sodium chloride; electrochemically reacting the sodium chloride; and carbonating the sodium hydroxide obtained after the electrochemical reaction.

[0018] The method for manufacturing lithium carbonate according to the present invention has the advantage of allowing the residue generated by the carbonate leaching method to be recycled throughout the industry, specifically in cement processes, without landfilling, by mixing the residue with hydrochloric acid to separate Na and then separating the solid and liquid phases.

[0019] In addition, hydrochloric acid generated during the process can be recycled by mixing it with the residue, and sodium hydroxide has the advantage of being recyclable by converting it back into sodium carbonate through a carbonator.

[0020]

[0021] Step of preparing lithium-containing ore

[0022] A method for producing lithium carbonate according to the present invention comprises the step of preparing an ore containing lithium.

[0023] In one embodiment of the present invention, the lithium-containing ore may comprise one or more selected from the group consisting of spodumene, petalite, lepidolite, hectorite, eucryptite, jadarite, zinnwaldite, and amblygonite.

[0024] In another embodiment of the present invention, the lithium-containing ore may include spodumene.

[0025] The above spodumene is desirable because it has the advantages of having a relatively high lithium content compared to other lithium-containing ores, low energy consumption in the processing process, and excellent purity of extracted lithium.

[0026] Specifically, the above spodumene may have a Li content of 1.4 weight% or more with respect to the total weight, more specifically 1.4 to 3.0 weight%.

[0027] If the above Li content is less than 1.4 weight%, the amount of residue generated may increase by about twofold, which may result in slightly lower economic efficiency, so it is desirable for the above Li2O content to satisfy the above range.

[0028]

[0029] Calcining lithium-containing ore

[0030] A method for producing lithium carbonate according to the present invention comprises the step of calcining the aforementioned lithium-containing ore.

[0031] In another embodiment of the present invention, the step of calcining the lithium-containing ore may be performed at 800 to 1,100°C, preferably 900 to 1,100°C, more preferably 930 to 1,050°C.

[0032] When the above calcination temperature satisfies the above range, it is desirable that the alpha phase of the lithium-containing ore, specifically spodumene, is sufficiently converted to the beta phase while minimizing the energy required for the calcination.

[0033]

[0034] In another embodiment of the present invention, the step of calcining the lithium-containing ore may be a step of converting the alpha phase of the lithium-containing ore, specifically spodumene, into a beta phase.

[0035] The above spodumene is an ore having the composition of lithium aluminosilicate (LiAl(SiO3)2) and exists in an alpha-phase crystal structure in its natural state. Alpha spodumene has a very stable crystal structure and low chemical reactivity, which makes direct lithium extraction difficult.

[0036] Therefore, by calcining the lithium-containing ore, the crystal structure is modified to convert the crystal structure of the alpha phase into a more reactive beta phase.

[0037] Through the above calcination step, cracks occur inside the spodumene concentrate, causing the structure to expand and the bonding between particles to weaken, thereby increasing the surface area. As a result, there is an advantage in that reactivity with acid or alkali solutions is improved, making it easier to elute lithium ions.

[0038]

[0039] The above calcination can be performed in an air atmosphere under atmospheric pressure and can be performed for 1 to 6 hours, preferably 1 to 5 hours, more preferably 1 to 3 hours.

[0040] If the above calcination is performed within the above time range, it is desirable that the conversion of the spodumene to the beta phase can be sufficiently achieved while minimizing the process time.

[0041]

[0042] The method for manufacturing lithium carbonate according to the present invention may further include the step of crushing the calcined lithium-containing ore.

[0043] The crushing above may be performed using a crusher so that the average particle size of the lithium-containing ore is 150 μm or less, preferably 100 μm or less, more preferably 50 to 100 μm, but is not limited thereto.

[0044] If the step of crushing the lithium-containing ore so that its average particle size satisfies the above range is further included, it would be more preferable in the high-temperature, high-pressure leaching step described later.

[0045] Specifically, since the reaction area can be more effectively secured within a given average particle size range, it is advantageous for increasing the efficiency required by the mentioned unit process. This is not limited to the aforementioned unit process alone; if based on a continuous lithium production process, it is expected to have a positive effect on the efficiency of subsequent processes following the unit processes. Therefore, it is desirable to have the advantage of excellent lithium leaching efficiency from the lithium-containing ore.

[0046]

[0047] High temperature and high pressure leaching step

[0048] A method for producing lithium carbonate according to the present invention comprises the step of mixing sodium carbonate and water with the calcined lithium-containing ore and leaching at high temperature and high pressure to obtain a leachate containing lithium carbonate particles.

[0049] The step of obtaining a leachate containing lithium carbonate particles by mixing sodium carbonate and water with the above-mentioned lithium-containing ore and leaching at high temperature and high pressure; may include the reaction of the following reaction scheme 1.

[0050]

[0051] [Reaction Equation 1]

[0052] 2LiAl(SiO3)2+ Na2CO3→ Li2CO3+ 2NaAl(SiO3)2

[0053]

[0054] In another embodiment of the present invention, in the step of obtaining a leachate containing lithium carbonate particles by mixing sodium carbonate and water with the calcined lithium-containing ore and leaching at high temperature and high pressure; wherein the sodium carbonate may be added in an amount of 1.0 to 1.5 equivalents, preferably 1.1 to 1.5 equivalents, and more preferably 1.2 to 1.5 equivalents based on the lithium equivalent in the calcined lithium-containing ore.

[0055] When the sodium carbonate is added in the above equivalent ratio, it is desirable to suppress the phenomenon of a decrease in the lithium recovery rate and to suppress the phenomenon where the sodium concentration remaining in the leaching solution increases excessively due to the addition of too much sodium carbonate, thereby requiring additional processing steps and costs for sodium removal.

[0056]

[0057] The above water can play a role in promoting the reaction between the lithium-containing ore and the sodium carbonate, and can play a role in forming internal pressure.

[0058] Specifically, the water can play a role in helping the ionization of the lithium-containing ore and the sodium carbonate so that the reaction can proceed smoothly.

[0059] The above water may be added in an amount of 1 to 5 times, preferably 1.5 to 4 times, and more preferably 2 to 3.5 times, relative to the total weight of the calcined lithium-containing ore.

[0060] When the above water is introduced within the above range, it is desirable as it has the advantage of excellent reaction efficiency and the ability to promote a uniform reaction.

[0061]

[0062] In another embodiment of the present invention, the step of mixing sodium carbonate and water with the calcined lithium-containing ore and leaching at high temperature and high pressure to obtain a leachate containing lithium carbonate particles may be performed at 180 to 250°C, preferably 190 to 230°C, more preferably 200 to 230°C.

[0063] It is desirable that the above high-temperature, high-pressure leaching step be performed within the above temperature range, as this can maximize the leaching rate of lithium.

[0064]

[0065] The step of obtaining a leachate containing lithium carbonate particles by mixing sodium carbonate and water with the calcined lithium-containing ore and leaching at high temperature and high pressure; can be performed under a pressure of 15 to 23 bar, preferably 18 to 23 bar, more preferably 20 to 23 bar.

[0066] It is desirable that the above high-temperature, high-pressure leaching step be performed under the above pressure range, as this can maximize the leaching rate of lithium.

[0067]

[0068] The above high temperature and high pressure leaching can be performed for 0.5 to 3 hours, preferably 1 to 3 hours, and more preferably 1.5 to 2.5 hours.

[0069] When the above high-temperature, high-pressure leaching is performed within the above time range, it is desirable that sufficient leaching of lithium is achieved while minimizing the process time.

[0070]

[0071] The process of mixing sodium carbonate and water with the above-described calcined lithium-containing ore and leaching at high temperature and high pressure to obtain a leachate containing lithium carbonate particles may be performed using an autoclave, but is not limited thereto.

[0072]

[0073] In another embodiment of the present invention, the step of obtaining a leaching solution containing the lithium carbonate particles may have a lithium leaching rate of 90% or more, specifically 93% or more, and more specifically 95% or more. In short, most of the lithium contained in the lithium-containing ore can be extracted.

[0074]

[0075] Step of obtaining an aqueous lithium bicarbonate solution

[0076] A method for producing lithium carbonate according to the present invention comprises the step of obtaining an aqueous lithium carbonate solution by bicarbonating the aforementioned leaching solution.

[0077] Specifically, the above-mentioned leaching solution may consist of residue and solid lithium carbonate, in other words, lithium carbonate particles, and lithium carbonate in a partially dissolved state.

[0078] The above-mentioned solid lithium carbonate is dissolved through bicarbonation and converted into lithium bicarbonate (LiHCO3), and some of the lithium carbonate dissolved in the leaching solution can also be converted into lithium bicarbonate.

[0079] The above-mentioned bicarbonate oxidation may be performed at 10 to 20°C, but is not limited thereto. However, it is preferable that the bicarbonate oxidation be performed at the above temperature to increase the selectivity of the reaction.

[0080]

[0081] The above bicarbonation may be performed, for example, by injecting carbon dioxide into the above lithium bicarbonate aqueous solution, but is not limited thereto.

[0082] Since the above lithium bicarbonate has a relatively higher solubility than lithium carbonate, there is an advantage in being able to recover lithium of higher purity by proceeding with the above bicarbonation.

[0083]

[0084] The above carbon dioxide may be introduced in a range of 1.0 to 1.5 equivalents, specifically 1.0 to 1.2 equivalents, based on the lithium bicarbonate equivalent.

[0085] It is desirable when the carbon dioxide is introduced within the above equivalent range because the reaction efficiency is excellent.

[0086]

[0087] The above lithium bicarbonate aqueous solution may have a lithium concentration of 1.5 to 3.5 g / L, specifically 1.5 to 3.0 g / L, and more specifically 2.0 to 2.5 g / L.

[0088] The fact that the lithium concentration of the above lithium bicarbonate aqueous solution satisfies the above range may mean that lithium has been extracted to the maximum extent.

[0089] The above lithium bicarbonate aqueous solution may have a sodium concentration of 3.7 to 46 g / L or less, specifically 10 to 31 g / L, and more specifically 15 to 23 g / L.

[0090] If the sodium concentration of the above lithium bicarbonate aqueous solution satisfies the above range, there is an advantage of minimizing Na impurities and maximizing lithium extraction.

[0091]

[0092] Step to obtain lithium bicarbonate filtrate and residue

[0093] The method for manufacturing lithium carbonate according to the present invention comprises the step of separating the solid and liquid of the aforementioned lithium bicarbonate aqueous solution to obtain a lithium bicarbonate filtrate and a residue.

[0094]

[0095] The above-mentioned solid-liquid separation may be performed using methods commonly used in the industry. For example, the above-mentioned solid-liquid separation may be performed using a pressurized solid-liquid separation device or a clarifier, but is not limited thereto.

[0096] By separating the above lithium bicarbonate aqueous solution and the above residue into solid and liquid phases, the residue can be recycled by mixing it with hydrochloric acid, which will be described later.

[0097]

[0098] In another embodiment of the present invention, the method may further include the step of separating the lithium bicarbonate aqueous solution into solid and liquid phases to obtain a lithium bicarbonate filtrate and a residue; the step of purifying the lithium bicarbonate filtrate; and the step of decarbonizing the purified lithium bicarbonate filtrate.

[0099] The above purification may be performed using a filtering device, an ion exchange resin, etc., but is not limited thereto.

[0100] If the above purification step is further performed, impurities that may be contained in the lithium bicarbonate filtrate can be removed, making it desirable to obtain lithium carbonate of excellent purity.

[0101]

[0102] The above decarbonation may be performed by methods such as removing carbon dioxide by thermally decomposing the lithium bicarbonate filtrate at a high temperature, but is not limited thereto.

[0103] Specifically, the lithium bicarbonate filtrate can be heated to a temperature of 80 to 95°C to remove carbon dioxide and precipitate lithium carbonate to obtain a lithium carbonate slurry, and lithium carbonate can be obtained by separating the lithium carbonate slurry from solid to liquid again.

[0104]

[0105] Step of mixing residue with hydrochloric acid

[0106] The method for manufacturing lithium carbonate according to the present invention comprises the step of mixing the solid-liquid separated residue with hydrochloric acid.

[0107] The above residue is mainly composed of NaAl(SiO3)2, and since NaAl(SiO3)2 cannot be recycled, it must be disposed of by landfill.

[0108] However, the present invention has the advantage of being recyclable across various industries by mixing and reacting the residue with hydrochloric acid to remove the Na component.

[0109] Specifically, the step of mixing the above residue with hydrochloric acid may include the reaction of Reaction Scheme 2 below.

[0110]

[0111] [Reaction Equation 2]

[0112] NaAl(SiO3)2+ HCl → HAl(SiO3)2+ NaCl

[0113]

[0114] The above hydrochloric acid may be mixed in an amount of 1 to 1.5 equivalents, preferably 1 to 1.3 equivalents, based on the amount of Na equivalents contained in the residue.

[0115] When the above hydrochloric acid is mixed within the above range, the conversion of the residue is sufficiently achieved, making it easy to remove sodium, which is desirable.

[0116]

[0117] The step of mixing the residue with hydrochloric acid can be performed at room temperature, specifically at a temperature of 20 to 25°C for 0.5 to 5 hours, preferably 1 to 5 hours, more preferably 1 to 3 hours.

[0118] When the step of mixing the residue with hydrochloric acid is performed within the temperature and time range, it is desirable that the change in the residue is sufficiently achieved and sodium is sufficiently removed while minimizing the process time and energy required for the process.

[0119]

[0120] Step of electrochemical reaction of sodium chloride

[0121] The method for producing lithium carbonate according to the present invention comprises the step of mixing the aforementioned residue with hydrochloric acid; and the step of electrochemically reacting the sodium chloride obtained in the above step.

[0122] Specifically, the step of electrochemically reacting the sodium chloride can be performed by introducing the sodium chloride into a bipolar electrodialysis (BPED) device.

[0123] The above sodium chloride can be obtained through solid-liquid separation with the above HAl(SiO3)2, and the above solid-liquid separation can be performed using the aforementioned method.

[0124]

[0125] The step of electrochemically reacting the sodium chloride above may include the reaction of Reaction Scheme 3 below.

[0126] [Reaction Equation 3]

[0127] NaCl + H2O + e → NaOH + HCl

[0128]

[0129] The method for producing lithium carbonate according to the present invention can obtain sodium hydroxide and hydrochloric acid by electrochemically reacting sodium chloride obtained by mixing the residue with hydrochloric acid.

[0130]

[0131] In another embodiment of the present invention, the method may further include the step of reintroducing the hydrochloric acid obtained after the electrochemical reaction into the step of mixing the solid-liquid separated residue with the hydrochloric acid.

[0132] In summary, the method for manufacturing lithium carbonate according to the present invention has the excellent advantage of being able to recycle sodium chloride by adding and mixing hydrochloric acid with residue that previously had to be disposed of by landfill, and then obtaining sodium hydroxide and hydrochloric acid by electrochemically reacting the sodium chloride, and subsequently reintroducing the hydrochloric acid into the process for obtaining sodium chloride.

[0133]

[0134] carbonation step of sodium hydroxide

[0135] The method includes the step of carbonating the sodium hydroxide obtained after the electrochemical reaction according to the present invention.

[0136] In another embodiment of the present invention, the step of carbonating the sodium hydroxide may be performed using a carbonation gas or a carbonate-containing material.

[0137] The above carbonation may involve reacting with carbonated gas or a carbonated substance.

[0138] For example, the above carbonation can be performed by CO2 gas, etc.

[0139]

[0140] The above carbonated gas material can be introduced in an amount of 1.0 to 1.5 equivalents, specifically 1.0 to 1.2 equivalents, based on the sodium hydroxide equivalent.

[0141] It is desirable when the above carbonated gas material is introduced within the above equivalent range because the reaction efficiency is excellent.

[0142]

[0143] In another embodiment of the present invention, the step of carbonating the sodium hydroxide may be performed using carbon dioxide.

[0144] Specifically, when the step of carbonating the sodium hydroxide is performed using carbon dioxide gas (CO2 gas), it is desirable because it offers the advantages of superior reaction efficiency and a simple process compared to other carbonation gases or carbonate-containing materials, making it cost-effective.

[0145]

[0146] The step of carbonating the sodium hydroxide above may include the reaction of Reaction Formula 4 below.

[0147] [Reaction Equation 4]

[0148] NaOH + CO2 → Na2CO3

[0149]

[0150] In another embodiment of the present invention, the method may further include the step of re-introducing the sodium carbonate obtained in the step of carbonating the sodium hydroxide into the step of leaching the calcined lithium-containing ore by mixing the sodium carbonate and water and performing high temperature and high pressure leaching.

[0151] In short, sodium carbonate produced by carbonizing the sodium hydroxide can be introduced together with water into the step of leaching the calcined lithium-containing ore at high temperature and high pressure to obtain an aqueous lithium carbonate solution and a residue.

[0152]

[0153] The method for manufacturing lithium carbonate according to the present invention has the advantage of efficiently producing high-purity lithium carbonate. Furthermore, by reacting residues that would otherwise have had to be disposed of by landfilling with hydrochloric acid to remove Na, the residues are converted into a form usable in cement processes, and the sodium chloride and hydrochloric acid obtained during this process can be recycled during the process, thereby reducing the amount of auxiliary raw materials used, which offers economic and environmental advantages.

[0154]

[0155] Preferred embodiments and comparative examples of the present invention are described below. However, the following examples are merely preferred embodiments of the present invention, and the present invention is not limited to the following examples.

[0156]

[0157] Examples

[0158] Spodumene concentrate with a Li2O content of 2.1 wt% was prepared and calcined at 1,050°C for 1 hour and 30 minutes under air to convert the alpha phase into the beta phase.

[0159] Afterwards, the calcined spodumene concentrate was crushed using a crusher to a particle size of 75㎛.

[0160] Subsequently, 1.2 equivalents of Na2CO3 were added to 1 equivalent of lithium in the calcined spodumene concentrate, and water was added in a ratio of 2 times the total weight of the calcined spodumene concentrate and mixed. The mixture was then subjected to high temperature and high pressure leaching at 200°C and 20 bar for 2 hours to obtain a leaching solution containing lithium carbonate particles. At this time, the leaching rate of lithium was 97.3%, and the composition of the leaching solution is shown in Table 1 below.

[0161]

[0162] Ion concentration in solution (g / L) LiSPBKNaSiEtc.2.26 0.01 0.01 N.D 0.92 16.2 0.74 <0.003

[0163]

[0164] Then, 1.2 equivalents of carbon dioxide gas were introduced into the leachate based on the equivalents of lithium carbonate to perform bicarbonation, thereby obtaining an aqueous lithium bicarbonate solution. At this time, the conversion rate of lithium (Li → 2LiHCO3) was 95.7%.

[0165] The obtained aqueous lithium bicarbonate solution was separated into solid and liquid phases to obtain a lithium bicarbonate filtrate and a residue, and the residue was mixed with hydrochloric acid. At this time, hydrochloric acid was added in an amount of 1.3 equivalents based on 1 equivalent of Na in the residue, and mixed at room temperature for 2 hours to obtain the residue reacted with hydrochloric acid and sodium chloride.

[0166] Sodium chloride was fed into the BPED process and converted into sodium hydroxide and hydrochloric acid, and the hydrochloric acid obtained at this time was recycled in a step of mixing the residue with hydrochloric acid.

[0167] Sodium hydroxide was converted into sodium carbonate by carbonating it using a carbonator with CO2 gas, and the obtained sodium carbonate was recycled by mixing it with calcined spodumene concentrate.

[0168] Figures 1 and 2 show the results of analyzing the components of the residue obtained by solid-liquid separation of an aqueous lithium bicarbonate solution and the residue reacted with hydrochloric acid, respectively. Specifically, Figures 1 and 2 show the results of XRD analysis of the components of the residue before and after reaction with hydrochloric acid.

[0169] Referring to Figures 1 and 2, it can be seen that the residue obtained by solid-liquid separation of an aqueous lithium bicarbonate solution has the structure of NaAl(SiO3)2, whereas the residue reacted with hydrochloric acid has the structure of HAl(SiO3)2. Specifically, it can be seen that the residue reacted with hydrochloric acid has the Na component removed and is converted into a recyclable component.

[0170]

[0171] The present invention is not limited to the above embodiments and can be manufactured in various different forms, and those skilled in the art will understand that the invention can be implemented in other specific forms without changing the technical concept or essential features of the invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive.

Claims

1. A step of preparing a lithium-containing ore; A step of calcining the above lithium-containing ore; A step of obtaining a leachate containing lithium carbonate particles by mixing sodium carbonate and water with the calcined lithium-containing ore and leaching at high temperature and high pressure; A step of obtaining an aqueous lithium bicarbonate solution by bicarbonating the above leaching solution; A step of separating the above lithium bicarbonate aqueous solution into solid and liquid phases to obtain a lithium bicarbonate filtrate and a residue; A step of mixing the above residue with hydrochloric acid to obtain sodium chloride; The step of electrochemically reacting the above sodium chloride; and A step of carbonating the sodium hydroxide obtained after the above electrochemical reaction; A method for manufacturing lithium carbonate including 2. In Paragraph 1, A step of separating the above lithium bicarbonate aqueous solution into solid and liquid phases to obtain a lithium bicarbonate filtrate and a residue; thereafter, Step of purifying the above lithium bicarbonate filtrate; and A method for manufacturing lithium carbonate, further comprising the step of decarbonizing the purified lithium bicarbonate filtrate.

3. In Paragraph 1, The step of carbonating the sodium hydroxide above; is, A method for manufacturing lithium carbonate using carbonate gas or a carbonate-containing material.

4. In Paragraph 1, In the step of obtaining a leachate containing the above lithium carbonate particles, A method for producing lithium carbonate in which the sodium carbonate is added in an amount of 1.0 to 1.5 equivalents based on the lithium equivalent in the calcined lithium-containing ore.

5. In Paragraph 1, The step of calcining the above lithium-containing ore; is, A method for manufacturing lithium carbonate, which is performed at 800 to 1,100℃.

6. In Paragraph 1, The step of calcining the above lithium-containing ore; is, A method for producing lithium carbonate comprising the step of converting the alpha phase of the lithium-containing ore into the beta phase.

7. In Paragraph 1, A method for manufacturing lithium carbonate, wherein the step of mixing sodium carbonate and water with the above-described calcined lithium-containing ore and leaching at high temperature and high pressure to obtain a leachate containing lithium carbonate particles is performed at 180 to 250°C.

8. In Paragraph 1, A method for producing lithium carbonate, wherein the step of mixing sodium carbonate and water with the above-described calcined lithium-containing ore and leaching at high temperature and high pressure to obtain a leachate containing lithium carbonate particles is performed at 15 to 23 bar.

9. In Paragraph 1, In the step of obtaining a leachate containing the above lithium carbonate particles, A method for manufacturing lithium carbonate having a lithium leaching rate of 90% or more.

10. In Paragraph 1, A method for manufacturing lithium carbonate, further comprising the step of reintroducing the hydrochloric acid obtained after the above electrochemical reaction into the step of mixing the above solid-liquid separated residue with the hydrochloric acid.

11. In Paragraph 1, A method for manufacturing lithium carbonate, further comprising the step of carbonating the sodium hydroxide; the step of reintroducing the sodium carbonate obtained in the carbonation step into the step of mixing the sodium carbonate and water with the calcined lithium-containing ore and leaching it at high temperature and high pressure.

12. In Paragraph 1, A method for producing lithium carbonate in which the lithium-containing ore comprises one or more selected from the group consisting of spodumene, petalite, lepidolite, hectorite, eucryptite, zadarite, zinmaldite, and amblygonite.

13. In Paragraph 12, A method for recovering lithium in which the above lithium-containing ore contains spodumene.

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