Method of adsorbing / desorbing lithium

Abstract

One embodiment of the present invention can provide a method of absorbing / desorbing lithium, comprising: an adsorption step of passing a lithium-containing solution through an adsorbent so as to obtain a lithium-adsorbed adsorbent; a washing step of passing a pretreatment solution through the lithium-adsorbed adsorbent so as to remove impurities; and a desorption step of passing a medium through the lithium-adsorbed adsorbent so as to obtain a lithium-containing desorption solution, wherein the pretreatment solution suppresses the desorption of the lithium adsorbed on the adsorbent in the washing step.

Description

Lithium adsorption and desorption method

[0001] The present invention relates to a method for adsorption and desorption of lithium.

[0002] Lithium secondary batteries are essential components in small devices such as cell phones and laptops, and demand for them is also increasing as a power source for hybrid and electric vehicles. Consequently, demand for lithium, a key raw material for lithium secondary batteries, is also skyrocketing.

[0003] Lithium, a key material in these lithium secondary batteries, is typically extracted from minerals, seawater, and brine. However, the Earth's crust only contains 0.006% lithium, and due to its high reactivity, it is not found in nature in pure metallic form. Therefore, it is typically extracted in the form of lithium compounds, Li2CO3 and LiOH·H2O, rather than in pure metallic form.

[0004] In addition, although seawater is abundant worldwide, its lithium content is low at 0.17 mg / L, which makes lithium extraction efficiency low and increases the production cost compared to other lithium raw materials.

[0005] The most common method for extracting lithium is to evaporate the water from brine and then add a carbonate to extract lithium carbonate. However, to extract lithium carbonate using carbonate, the brine must be concentrated to an economically viable level before the lithium extraction process can begin. However, brine capable of improving the economic feasibility of lithium extraction is limited worldwide.

[0006] Therefore, the development of a technology capable of economically and efficiently recovering lithium from lithium-containing solutions is urgent. One such method is selective lithium adsorption and desorption using adsorbents.

[0007] In one embodiment of the present invention, a process for recovering lithium using an adsorption and desorption technique using an adsorbent is provided, which includes a washing step in the middle, thereby enabling more economical and effective recovery of lithium.

[0008] A lithium adsorption and desorption method according to one embodiment of the present invention comprises an adsorption step of passing a lithium-containing solution through an adsorbent to obtain an adsorbent having lithium adsorbed thereon; a washing step of passing a pretreatment solution through the lithium-adsorbed adsorbent to remove impurities; and a desorption step of passing a medium through the lithium-adsorbed adsorbent to obtain a lithium-containing desorption solution; wherein the pretreatment solution suppresses desorption of lithium adsorbed to the adsorbent in the washing step.

[0009] The concentration of total dissolved solids in the above pretreatment solution may range from 0.5 to 3.0 mol / L.

[0010] The above pretreatment solution may be a solution containing an anion corresponding to the adsorbed lithium.

[0011] The above pretreatment solution may be a solution containing one or more salts selected from the group consisting of sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), and lithium (Li).

[0012] The above pretreatment solution may be a solution containing at least one selected from the group consisting of NaCl, KCl, CaCl2, MgCl2, and LiCl.

[0013] The above pretreatment solution may be a solution containing lithium at a concentration of 0.05 to 3.0 g / L throughout the entire pretreatment solution.

[0014]

[0015] The lithium concentration of the lithium-containing solution in the above adsorption step may be 0.03 to 2.0 g / L.

[0016] The lithium concentration of the medium used in the above desorption step may be 0.05 to 1.50 g / L.

[0017] With respect to the amount of lithium present in the adsorbent after the above adsorption step, the amount of lithium contained in the pretreatment solution after the above washing step may be in the range of 0.1 to 10.0 wt%.

[0018] With respect to the amount of lithium present in the adsorbent after the above adsorption step, the amount of lithium obtained in the above desorption step may be in the range of 90.0 to 99.9 wt%.

[0019] The above adsorbent may be an aluminum-based adsorbent.

[0020] It may further include a step of concentrating the entire desorption liquid obtained through the above desorption step.

[0021] A method for adsorbing and desorbing lithium according to one embodiment of the present invention can economically and effectively improve the lithium recovery rate by desorbing lithium using a solution containing anions corresponding to the adsorbed lithium.

[0022] Figure 1 is data on the amount of lithium desorption according to the total dissolved solids concentration conditions in the pretreatment solution in the washing step according to one embodiment of the present invention.

[0023] Figure 2 is lithium concentration data according to the amount of solution passing through the adsorbent in the washing step and desorption step according to one embodiment of the present invention.

[0024] Figure 3 is lithium concentration data according to the amount of solution passing through the adsorbent in the lithium desorption step according to a comparative example of the present invention.

[0025] Figure 4 is sodium concentration data according to the amount of solution passing through the adsorbent in the lithium desorption step according to a comparative example of the present invention.

[0026] Figure 5 is data of lithium concentration and calcium concentration according to BV in the washing step and the desorption step according to one embodiment of the present invention.

[0027] Figure 6 is data on lithium concentration and calcium concentration according to BV in a lithium desorption step according to a comparative example of the present invention.

[0028] In the specification of the present invention, terms such as first, second, and third are used to describe various parts, components, regions, layers, and / or sections, but are not limited thereto. These terms are used only to distinguish one part, component, region, layer, or section from another part, component, region, layer, or section. Accordingly, a first part, component, region, layer, or section described below may be referred to as a second part, component, region, layer, or section without departing from the scope of the present invention.

[0029] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the present invention. As used herein, the singular forms "singular" and "comprising" include plural forms as well, unless the context clearly dictates otherwise. The word "comprising" as used herein specifies a particular feature, region, integer, step, operation, element, and / or component, but does not exclude the presence or addition of other features, regions, integers, steps, operations, elements, and / or components.

[0030] When a part is referred to as being "on" or "over" another part, it can be directly on or over the other part, or there may be other parts intervening. Conversely, when a part is referred to as being "directly on" another part, there are no other parts intervening.

[0031] Although not defined otherwise, all terms, including technical and scientific terms, used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention pertains. Terms defined in commonly used dictionaries are further interpreted to have meanings consistent with the relevant technical literature and the present disclosure, and are not to be construed as ideal or overly formal unless otherwise defined.

[0032] Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement them. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0033]

[0034] Lithium adsorption and desorption method

[0035] As previously mentioned, there is a need to economically and efficiently recover lithium from lithium-containing solutions. In this embodiment, this problem was solved by implementing a process to remove impurities using a pretreatment solution between the adsorption and desorption of lithium using an adsorbent.

[0036] Specifically, a lithium adsorption and desorption method according to one embodiment may include an adsorption step of passing a lithium-containing solution through an adsorbent to obtain an adsorbent having lithium adsorbed thereon; a washing step of passing a pretreatment solution through the lithium-adsorbed adsorbent to remove impurities; and a desorption step of passing a medium through the lithium-adsorbed adsorbent to obtain a lithium-containing desorption solution; wherein the pretreatment solution suppresses desorption of lithium adsorbed to the adsorbent in the washing step.

[0037] The above adsorption step refers to a step of adsorbing lithium from a lithium-containing solution. Specifically, it may be a step of adsorbing lithium onto the adsorbent by passing the lithium-containing solution through the adsorbent.

[0038] At this time, the lithium concentration of the lithium-containing solution may be in the range of 0.03 g / L to 2.0 g / L, more specifically, 0.1 g / L to 2.0 g / L or 0.5 g / L to 1.5 g / L. If the lithium concentration of the lithium-containing solution is less than 0.03 g / L, lithium may not be well adsorbed to the adsorbent, which may lower the adsorption efficiency, and the need to operate a plurality of adsorption columns may increase, which may lower the economic efficiency. In addition, if the lithium concentration of the lithium-containing solution exceeds 2.0 g / L, the time taken for the adsorbent to reach the breakthrough point is fast, which requires the operation of a plurality of adsorption columns, which may relatively lower the economic efficiency. Therefore, it is preferable that the lithium concentration included in the lithium-containing solution satisfies the above range.

[0039] The above adsorbent is for adsorbing lithium dissolved in the lithium-containing solution, and may be an aluminum-based adsorbent, and may include, for example, aluminum hydroxide. When an aluminum-based adsorbent including aluminum hydroxide is used as in the present embodiment, the amount of lithium dissolved in the lithium-containing solution is high, and since there is almost no aluminum loss in the desorption process described later, the life of the adsorbent is long, and thus the economic efficiency of the lithium extraction process is excellent.

[0040] Additionally, the aluminum-based adsorbent may be a molded body including adsorbent powder and a binder.

[0041] The above adsorbent powder may be, for example, an adsorbent powder containing aluminum hydroxide. The advantages of using an adsorbent powder containing aluminum hydroxide are the same as those described above.

[0042] The binder is used to form a molded body of the adsorbent powder into an appropriate shape and serves to bind the adsorbent powder together. The binder may include, for example, at least one of polyvinyl chloride (PVC), polysulfone, and polyaniline. In particular, in the present embodiment, the binder preferably includes polyvinyl chloride (PVC), which can provide excellent binding strength between the adsorbent powders.

[0043] Meanwhile, the step of passing a lithium-containing solution through an aluminum-based adsorbent to adsorb lithium onto the aluminum-based adsorbent includes, for example, the reaction of the following reaction formula 1.

[0044] [Reaction Formula 1]

[0045] LiCl (1-x) .Al(OH)3.nH2O + xLiCl → LiCl.Al(OH)3.nH2O + (1-x)LiCl

[0046] A washing step may be performed after the adsorption step and before the desorption step. The washing step refers to a step of removing impurities by passing a pretreatment solution through the lithium-adsorbed adsorbent.

[0047] The above pretreatment solution may have a total dissolved solid (TDS) concentration in the range of 0.5 to 3.0 mol / L, specifically, 0.75 to 3.0 mol / L, 1.0 to 3.0 mol / L, 1.0 to 2.5 mol / L, 1.0 to 2.3 mol / L, or 1.0 to 2.0 mol / L. In this case, the total dissolved solid refers to a concentration obtained by including all salts regardless of the type of salt.

[0048] If the concentration of total dissolved solids is below the above range, lithium may be desorbed, which may lower the recovery rate of lithium and impurities may not be removed efficiently. In addition, if the concentration of total dissolved solids exceeds the above range, salt may act as an impurity. In particular, considering that the solubility of sodium chloride (NaCl), which accounts for more than 50 wt% of the total weight of total dissolved solids, is approximately 6.141 mol / L (approximately 358.9 g / L, @25℃), there is a problem that the precipitate is generated due to the saturated solution, making it difficult to perform the impurity removal process, and the load of the post-process may increase. Therefore, it is preferable that the total dissolved solids included in the pretreatment solution satisfy the above range.

[0049] At this time, the pretreatment solution may be a solution containing anions corresponding to the adsorbed lithium. Specifically, the anions are Cl - It can be. Since adsorption / desorption using an Al-based adsorbent is possible when Li in the solution is in the form of LiCl, it is preferable that the anion be Cl- since there is a possibility that the anion may act as an impurity in the future when pretreatment using other anions is performed.

[0050] Additionally, the pretreatment solution may be a solution containing one or more salts selected from the group consisting of sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), and lithium (Li).

[0051] Specifically, the pretreatment solution may be a solution containing at least one selected from the group consisting of NaCl, KCl, CaCl2, MgCl2, and LiCl.

[0052] In addition, the pretreatment liquid may contain lithium. By using a pretreatment liquid containing lithium, the influence of other impurities can be reduced, and if the washing liquid is mixed with the raw brine and extracted again, the loss of lithium may not be significant. At this time, the concentration of lithium contained in the pretreatment liquid may be 0.05 to 3.0 g / L, and specifically, 0.10 to 2.5 g / L, 0.15 to 2.0 g / L, 0.15 to 1.0 g / L, or 0.20 to 0.7 g / L. If it exceeds the above range, economic feasibility may be reduced, and if it falls below the range, it may be difficult to reduce the influence of other impurities.

[0053] Regarding the amount of lithium present in the adsorbent after the above adsorption step, the amount of lithium contained in the pretreatment liquid after passing through the adsorbent may be in the range of 0.1 to 10.0 wt%, and specifically, may be in the range of 0.5 to 8.0 wt%, 1.0 to 6.0 wt%, 1.0 to 4.0 wt%, or 1.0 to 2.5 wt%.

[0054] This means that the pretreatment solution inhibits the desorption of lithium adsorbed on the adsorbent in the washing step.

[0055]

[0056] After performing the washing step, a step of obtaining a lithium-containing desorption liquid is performed.

[0057] Specifically, a lithium-containing desorbent can be obtained by passing a medium (e.g., distilled water or an aqueous solution containing a lithium salt) through the lithium-adsorbed aluminum adsorbent.

[0058] At this time, the amount of medium passed through the lithium-adsorbed aluminum adsorbent may be 10 to 50 BV, more specifically 20 to 40 BV, based on 1 Bed volume (BV), which is the volume of the adsorbent column.

[0059] In the case of the total lithium-containing desorbent obtained by passing the medium through the adsorbent, most of the lithium adsorbed on the adsorbent must be desorbed so that the lithium concentration in the desorbent after passing 80 vol% of the desorbent is 0.2 g / L or less, specifically 0.1 g / L or 0.05 g / L, so that lithium can be adsorbed again using the adsorbent. Therefore, a step of passing an amount of the medium in the above range through the lithium-adsorbed aluminum adsorbent may be necessary.

[0060] Lithium hydroxide can be recovered through a desorption liquid having a high lithium concentration among the desorption liquids obtained through the desorption step, but is not limited thereto. Specifically, the lithium-containing desorption liquid can be used in the process up to the step of passing 10 BV of medium after the washing step in which impurities are removed, and preferably, the lithium-containing desorption liquid can be used in the process up to the step of passing 7 BV or 5 BV of medium, but this may vary depending on the shape of the desorption curve.

[0061] Regarding the amount of lithium present in the adsorbent after the above adsorption step, the amount of lithium obtained in the above desorption step may be in the range of 90.0 to 99.9 wt%, and specifically, in the range of 95.0 to 99.9 wt%.

[0062] When the washing step according to the present invention is not included, the amount of lithium lost relative to the amount of lithium present in the adsorbent after the adsorption step may be in the range of 10.0 to 50.0 wt%, specifically, in the range of 25.0 to 45.0 wt% or 30.0 to 40.0 wt%. The reason why such lithium loss occurs is that a lithium-containing desorbent containing a high concentration of impurities may be difficult to use in a lithium recovery process. The lower the concentration of impurities (salts other than lithium), the more preferable it is, and specifically, in the case of a lithium-containing desorbent containing impurities (salts other than lithium) of 20 g / L, 15 g / L or 10 g / L or less, the recovery rate of lithium hydroxide obtained after the subsequent process described below may be excellent.

[0063]

[0064] The step of passing a medium through the lithium-adsorbed aluminum adsorbent to obtain a lithium-containing desorbent includes, for example, the reaction of the following reaction formula 2.

[0065] [Reaction Formula 2]

[0066] LiCl·Al(OH)3·nH2O → LiCl (1-x) ·Al(OH)3·nH2O + xLiCl

[0067] In one embodiment of the present invention, the medium used in the desorption step may be an aqueous solution containing a lithium salt, specifically, an aqueous solution containing lithium chloride. In this case, the lithium concentration in the resulting desorption solution may be increased. This improvement in lithium concentration in the desorption solution may reduce the load on the subsequent concentration process.

[0068] Specifically, the lithium concentration in the medium may be in the range of 0.05 g / L to 1.50 g / L, and more specifically, 0.10 g / L to 1.00 g / L, 0.10 g / L to 0.80 g / L, or 0.10 g / L to 0.40 g / L. If the lithium concentration in the medium is below the above range, lithium (Li) contained in the aluminum adsorbent may be lost, causing damage to the LDH (Layered Double Hydroxide) structure, and if it exceeds the above range, adsorption rather than desorption may occur.

[0069] The concentration of lithium contained in the lithium-containing desorption liquid obtained by the above method may be 0.1 g / L to 3.0 g / L, or 0.2 g / L to 3.0 g / L, and more specifically, 0.8 g / L to 2.5 g / L.

[0070] A high lithium concentration in the desorption solution significantly reduces the amount of water required for subsequent concentration steps, significantly improving the burden of subsequent processes. In this case, the subsequent process may refer to the concentration step.

[0071] The lithium adsorption and desorption method according to one embodiment may further include a step of concentrating the entire desorption liquid obtained through the desorption step.

[0072] Specifically, the concentration step may include a process for concentrating the desorbed solution using reverse osmosis and electrodialysis, through which the target lithium concentration can be determined based on the properties of the intermediate material to be extracted. In addition to the above methods, if additional concentration is required, a depressurization / evaporation concentration step can be used to raise the lithium concentration to the desired level.

[0073]

[0074] Hereinafter, preferred embodiments of the present invention will be described. However, the following examples are only preferred embodiments of the present invention, and the present invention is not limited to the following examples.

[0075]

[0076] Experimental Example - Experiment to Confirm the Effect of Total Dissolved Solids Concentration on Lithium Extraction Inhibition

[0077] First, an experiment was conducted to confirm the appropriate concentration range of total dissolved solids in the pretreatment solution used in the washing step.

[0078]

[0079] A brine solution having the composition shown in Table 1 below was prepared.

[0080] Brine composition LiCaMgBKNa concentration value (mg / L) 75190001400300650049000

[0081] (A) Adsorption stage

[0082] 4 L of brine having the composition shown in Table 1 above was passed through an adsorbent containing aluminum hydroxide.

[0083] (B) Washing step

[0084] Distilled water and a sodium chloride aqueous solution with a concentration ranging from 0.2 to 6.2 mol / L were used as pretreatment solutions. After passing 0.2 L of the pretreatment solution, the concentration of lithium present in the washing solution was measured.

[0085]

[0086] Example

[0087] A brine having the same composition as in Table 1 above was prepared.

[0088] (A) Adsorption stage

[0089] The above 4 L of brine was passed through an adsorbent containing aluminum hydroxide.

[0090] (B) Washing step

[0091] Impurities were removed by passing 0.2 L of a sodium chloride aqueous solution with a concentration of 30 g / L (0.513 mol / L).

[0092] (C) Desorption stage

[0093] Next, 4 L of lithium chloride aqueous solution per volume was passed through the above adsorbent on which lithium was adsorbed to obtain a lithium-containing desorbent.

[0094] At this time, the amount of medium for performing one desorption step was defined as 1 bed volume (BV), and specifically, the desorption step was performed up to 40 BV under the desorption conditions of a temperature of 40°C and a flow rate of 30 mL / min using a lithium chloride aqueous solution having a concentration of 0.15 g / L.

[0095]

[0096] Comparative example

[0097] A brine solution having the composition shown in Table 2 below was prepared.

[0098]

[0099] Brine composition LiSCaMgBKNa concentration value (mg / L) 300 50 44000 1850 62 4000 72000

[0100] In the comparative example, the adsorption and desorption of lithium were performed in the same manner as in Example 1, except that the brine having the composition of Table 2 was used and the washing step in Example 1 was not performed.

[0101] The brine used in the comparative example has a higher impurity content in terms of other components (Ca, Na, K), including Li, compared to the brine used in the examples. This composition corresponds to the composition of geothermal brine, which is one of the resources classified as unconventional resources.

[0102] When adsorption is performed using a brine having the above composition, a relatively large amount of impurities (ions other than lithium) are deposited on the surface of the adsorbent. Specifically, unlike lithium, the impurities are not adsorbed within the lattice structure during the adsorption process, but rather exist on the surface of the adsorbent.

[0103] When the desorption process is performed without a washing step, impurities present on the surface of the adsorbent, as described above, are introduced into the medium when the medium is introduced. That is, impurities are included in the medium, and the concentration of total dissolved solids may temporarily exceed 0.5 mol / L.

[0104] That is, through this, it is possible to confirm whether there is a phenomenon of delayed desorption of lithium (Li) due to the concentration of total dissolved solids caused by impurities that dissolve into the medium from the surface of the adsorbent.

[0105]

[0106] The experimental results confirmed through the examples and comparative examples described above are as follows.

[0107] Figure 1 is data on the amount of lithium desorption according to the total dissolved solids concentration conditions in the pretreatment solution in the washing step according to one embodiment of the present invention.

[0108] Referring to Figure 1, as the concentration of total dissolved solids in the stripping solution decreases, more lithium (Li) adsorbed on the adsorbent is desorbed and exists in the stripping solution at a high concentration. Specifically, it can be confirmed that when the concentration of total dissolved solids is less than 0.5 mol / L, the amount of lithium present in the stripping solution exists at a concentration of 0.04 mol / L or more, resulting in lithium loss.

[0109] Specifically, since the initial desorption solution having a calcium concentration of 30 g / L or higher, which is a very high concentration, is confirmed to have some delay in lithium desorption in the initial desorption solution of 0.75 BV or lower in FIG. 6, it can be expected that the amount of lithium obtained in the subsequent desorption step can reach a range of 90.0 to 99.9 wt% even when the total dissolved solid concentration of the pretreatment solution in the washing step is 0.5 to 1.0 mol / L, when a large amount of impurities are included in the lithium-containing solution used in the adsorption step, and thus a high concentration of impurities exists on the surface of the adsorbent.

[0110] Figure 2 shows lithium concentration data according to the amount of solution passing through the adsorbent in the washing step and desorption step according to one embodiment of the present invention.

[0111] In Fig. 2, the gray section is data for which washing was performed using a pretreatment solution, and the area of ​​the section indicated is 13.961 g, which means the amount of lithium removed during the washing step.

[0112] Figure 3 is lithium concentration data according to the amount of solution passing through the adsorbent in the lithium desorption step according to a comparative example of the present invention.

[0113] In Fig. 3, the gray section is data from the initial desorption stage, and the area of ​​the section is 87.135 g, which means the amount of lithium desorbed in the initial desorption stage.

[0114] Figure 4 is sodium concentration data according to the amount of solution passing through the adsorbent in the lithium desorption step according to a comparative example of the present invention.

[0115] In Fig. 4, the gray section is data from the initial desorption stage, and the area of ​​the section is 4142.577 g, which means the amount of sodium desorbed in the initial desorption stage.

[0116] That is, as confirmed through Figures 3 and 4, the desorption liquid obtained in the initial desorption stage has a high content of impurities, making it difficult to utilize, and since the desorption liquid also contains lithium, it can be confirmed that the recovery rate of lithium is reduced as lithium is lost.

[0117] In addition, as confirmed through Figures 2 and 3, it can be confirmed that when impurities are removed through the initial washing step, the lithium recovery rate is further improved in the subsequent desorption step.

[0118] FIG. 5 is data of lithium concentration and calcium concentration according to BV in a washing step and a desorption step according to one embodiment of the present invention, and FIG. 6 is data of lithium concentration and calcium concentration according to BV in a lithium desorption step according to one comparative example of the present invention.

[0119] Through a comparison of FIGS. 5 and 6, it can be confirmed that calcium (Ca) is mostly desorbed within 2 BV regardless of the washing step, while lithium (Li) is desorbed within 2 BV in the example, which is 32.8 mg, which is 2% of the total amount of desorbed solution up to 30 BV, while in the comparative example, 174.2 mg, which is 32% of the total amount of desorbed solution up to 30 BV, is desorbed within 2 BV.

[0120] Specifically, referring to FIG. 6, when the washing step according to the present embodiment is not included, some delay in lithium desorption is confirmed in the initial desorption solution of 0.75 BV or less, which has a very high calcium concentration of 30 g / L, but the amount of total dissolved solids soon decreases, and it can be confirmed that lithium is desorbed at a high concentration in a section where impurities still exist at a high concentration, making selective separation from impurities difficult.

[0121] That is, if the washing step according to the present embodiment is not included, it can be confirmed that lithium is desorbed together with a high content of impurities in the initial desorption step, resulting in a low lithium recovery rate.

[0122]

[0123] The present invention is not limited to the above-described embodiments, but can be manufactured in a variety of different forms. Those skilled in the art will appreciate that the present invention can be implemented in other specific forms without altering the technical spirit or essential characteristics of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive.

Claims

1. An adsorption step of passing a lithium-containing solution through an adsorbent to obtain an adsorbent having lithium adsorbed thereon; A washing step for removing impurities by passing a pretreatment solution through the lithium-absorbed adsorbent; and A desorption step of obtaining a lithium-containing desorption solution by passing a medium through the lithium-adsorbed adsorbent; The above pretreatment solution suppresses the desorption of lithium adsorbed on the adsorbent in the above washing step. Method for adsorption and desorption of lithium.

2. In paragraph 1, The above pretreatment solution has a total dissolved solid concentration of 0.5 to 3.0 mol / L. Method for adsorption and desorption of lithium.

3. In paragraph 1, The above pretreatment solution is a solution containing anions corresponding to the adsorbed lithium. Method for adsorption and desorption of lithium.

4. In paragraph 1, The above pretreatment solution is a solution containing at least one salt selected from the group consisting of sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), and lithium (Li). Method for adsorption and desorption of lithium.

5. In paragraph 1, The above pretreatment solution is a solution containing at least one selected from the group consisting of NaCl, KCl, CaCl2, MgCl2 and LiCl. Method for adsorption and desorption of lithium.

6. In paragraph 1, The above pretreatment solution is a solution containing lithium at a concentration of 0.05 to 3.0 g / L throughout the entire pretreatment solution. Method for adsorption and desorption of lithium.

7. In paragraph 1, The lithium concentration of the lithium-containing solution in the above adsorption step is 0.03 to 2.0 g / L. Method for adsorption and desorption of lithium.

8. In paragraph 1, The lithium concentration of the medium used in the above desorption step is 0.05 to 1.50 g / L. Method for adsorption and desorption of lithium.

9. In paragraph 1, Regarding the amount of lithium present in the adsorbent after the above adsorption step, The amount of lithium contained in the pretreatment solution after the above washing step is in the range of 0.1 to 10.0 wt%. Method for adsorption and desorption of lithium.

10. In paragraph 1, Regarding the amount of lithium present in the adsorbent after the above adsorption step, The amount of lithium obtained in the above desorption step is in the range of 90.0 to 99.9 wt%, Method for adsorption and desorption of lithium.

11. In paragraph 1, The above adsorbent is an aluminum-based adsorbent. Method for adsorption and desorption of lithium.

12. In paragraph 1, It further includes a step of concentrating the entire desorption liquid obtained through the above desorption step; Method for adsorption and desorption of lithium.

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