Lithium adsorption and desorption methods

Abstract

An embodiment of the present invention provides a method for lithium adsorption and desorption, comprising: an adsorption step in which a lithium-containing solution is passed through an adsorbent to obtain an adsorbent with adsorbed lithium; a washing step in which a pretreatment liquid is passed through the lithium-adsorbed adsorbent to remove impurities; and a desorption step in which a medium is passed through the lithium-adsorbed adsorbent to obtain a lithium-containing desorbed liquid, wherein the pretreatment liquid inhibits the desorption of lithium adsorbed on the adsorbent during the washing step.

Description

Technical Field

[0001] This invention relates to a method for the adsorption and desorption of lithium. Background Technology

[0002] Lithium-ion batteries are an essential component of small devices such as mobile phones and laptops, and their demand is increasing recently as they serve as a power source for hybrid and electric vehicles. Consequently, the demand for lithium, the core raw material for lithium-ion batteries, is also rising sharply.

[0003] As the core material of this lithium-ion secondary battery, lithium is usually extracted from minerals, seawater, salt water, etc. However, the lithium content in the Earth's crust is only 0.006%, and due to its high reactivity, lithium does not exist in nature in a pure metallic form. It is usually extracted in the form of lithium compounds such as Li₂CO₃ and LiOH·H₂O, rather than in a pure metallic form.

[0004] In addition, although seawater is abundant globally, its lithium content is only 0.17 mg / L, which is low. Therefore, lithium extraction efficiency is low and production costs are higher than other lithium raw materials.

[0005] The most common method for lithium extraction is to evaporate the water from brine and then add carbonates to extract lithium in the form of lithium carbonate. However, in order to extract lithium carbonate by adding carbonates, the brine must be concentrated to an economically viable level before the lithium extraction process can proceed, and globally, the amount of brine available that can improve the economics of lithium extraction is limited.

[0006] Therefore, there is an urgent need to develop technologies for the economical and efficient recovery of lithium from lithium-containing solutions. As one such method, techniques utilizing adsorbents for the selective adsorption and desorption of lithium are being investigated. Summary of the Invention

[0007] (a) Technical problems to be solved One embodiment of the present invention aims to provide a lithium recovery process that can recover lithium more economically and efficiently by adding an intermediate washing step to the recovery technology that utilizes adsorbents for lithium adsorption and desorption.

[0008] (II) Technical Solution An adsorption and desorption method for lithium according to an embodiment of the present invention may include: an adsorption step in which a lithium-containing solution is passed through an adsorbent to obtain an adsorbent with adsorbed lithium; a washing step in which a pretreatment liquid is passed through the lithium-adsorbed adsorbent to remove impurities; and a desorption step in which a medium is passed through the lithium-adsorbed adsorbent to obtain a lithium-containing desorbed liquid, wherein the pretreatment liquid inhibits the desorption of lithium adsorbed on the adsorbent during the washing step.

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

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

[0011] 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).

[0012] The pretreatment solution may be a solution containing one or more of the following: NaCl, KCl, CaCl2, MgCl2, and LiCl.

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

[0014] The lithium concentration of the lithium-containing solution in the adsorption step can be from 0.03 to 2.0 g / L.

[0015] The lithium concentration of the medium used in the desorption step can be from 0.05 to 1.50 g / L.

[0016] The amount of lithium contained in the pretreatment solution after the washing step can range from 0.1 to 10.0 by weight, relative to the amount of lithium present in the adsorbent after the adsorption step.

[0017] The amount of lithium obtained in the desorption step can range from 90.0 to 99.9 by weight, relative to the amount of lithium present in the adsorbent after the adsorption step.

[0018] The adsorbent can be an aluminum-based adsorbent.

[0019] The method may also include a step of concentrating all the desorbed solution obtained through the desorption step.

[0020] (III) Beneficial Effects According to an embodiment of the present invention, the lithium adsorption and desorption method can improve the lithium recovery rate economically and efficiently by using a solution containing anions corresponding to the adsorbed lithium for lithium desorption. Attached Figure Description

[0021] Figure 1 This data pertains to the amount of lithium desorption during the washing step according to an embodiment of the present invention, which varies with the total dissolved solids concentration in the pretreatment solution.

[0022] Figure 2These are lithium concentration data varying with the amount of adsorbent solution passing through the washing and desorption steps according to an embodiment of the present invention.

[0023] Figure 3 These are lithium concentration data as a function of the amount of solution passing through the adsorbent during the lithium desorption step according to a comparative example of the present invention.

[0024] Figure 4 These are sodium concentration data as a function of the amount of solution passing through the adsorbent during the lithium desorption step according to a comparative example of the present invention.

[0025] Figure 5 These are lithium and calcium concentration data varying with BV during the washing and desorption steps according to an embodiment of the present invention.

[0026] Figure 6 These are lithium and calcium concentration data as a function of BV during the lithium desorption step according to a comparative example of the present invention. Detailed Implementation

[0027] In this specification, the terms "first," "second," "third," etc., are used to describe various parts, components, regions, layers, and / or segments, but these parts, components, regions, layers, and / or segments should not be limited by these terms. These terms are only used to distinguish one part, component, region, layer, and / or segment from another. Therefore, without departing from the scope of this invention, the first part, component, region, layer, and / or segment described below can also be described as a second part, component, region, layer, and / or segment.

[0028] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. Unless the context clearly indicates otherwise, the singular forms used are intended to include the plural forms as well. It should also be understood that the term "comprising" as used in the specification can specifically refer to a particular feature, domain, integer, step, action, element, and / or component, and does not exclude the presence or addition of other features, domains, integers, steps, actions, elements, and / or components.

[0029] When referring to a part as being "above" or "on top of" another part, it can mean that it is directly above or on top of the other part, or that there are other parts in between. When referring to a part as being "directly above" another part, there are no other parts in between.

[0030] Although not otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Terms defined in dictionaries should be interpreted as having the same meaning as disclosed in relevant technical literature and herein, and should not be interpreted in an idealized or overly formal sense.

[0031] The embodiments of the present invention will be described in detail below to enable those skilled in the art to readily implement the invention. However, the present invention can be implemented in various different ways and is not limited to the embodiments described herein.

[0032] Lithium adsorption and desorption methods As mentioned earlier, there is a need for the economical and efficient recovery of lithium from lithium-containing solutions. In this embodiment, these problems are solved by using a pretreatment solution to remove impurities during the intermediate stage of lithium adsorption and desorption using an adsorbent.

[0033] Specifically, a lithium adsorption and desorption method according to one embodiment may include: an adsorption step in which a lithium-containing solution is passed through an adsorbent to obtain an adsorbent with adsorbed lithium; a washing step in which a pretreatment liquid is passed through the lithium-adsorbent to remove impurities; and a desorption step in which a medium is passed through the lithium-adsorbent to obtain a lithium-containing desorbed liquid, wherein the pretreatment liquid inhibits the desorption of lithium adsorbed on the adsorbent during the washing step.

[0034] The adsorption step refers to the step of adsorbing lithium from a lithium-containing solution. Specifically, the lithium-containing solution can be passed through an adsorbent, thereby adsorbing lithium onto the adsorbent.

[0035] At this point, the lithium concentration of the lithium-containing solution can range from 0.03 g / L to 2.0 g / L, more specifically from 0.1 g / L to 2.0 g / L or from 0.5 g / L to 1.5 g / L. If the lithium concentration of the lithium-containing solution is below 0.03 g / L, lithium is not easily adsorbed onto the adsorbent, which may lead to a decrease in adsorption efficiency, and the increased need to operate multiple adsorption columns may result in a decrease in economic efficiency. Furthermore, if the lithium concentration of the lithium-containing solution exceeds 2.0 g / L, the time to reach the adsorbent breakthrough point is faster, requiring the operation of multiple adsorption columns, thus resulting in a relatively lower economic efficiency. Therefore, the lithium concentration of the lithium-containing solution preferably meets the range described above.

[0036] The adsorbent, used to adsorb lithium dissolved in the lithium-containing solution, can be an aluminum-based adsorbent, such as containing aluminum hydroxide. As described in this embodiment, when using an aluminum-based adsorbent containing aluminum hydroxide, the adsorption capacity for lithium dissolved in the lithium-containing solution is high, and there is almost no aluminum loss in the desorption process described later. Therefore, the adsorbent has a long lifespan and offers the advantage of excellent economic efficiency in lithium extraction processes.

[0037] In addition, the aluminum-based adsorbent can be a molded body containing adsorbent powder and binder.

[0038] The 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.

[0039] The binder is used to prepare the adsorbent powder into a molded body of suitable shape, thereby binding the adsorbent powder together. The binder may include, for example, at least one of polyvinyl chloride (PVC), polysulfone, and polyaniline. In particular, in this embodiment, the binder preferably includes polyvinyl chloride (PVC), which provides excellent bonding between the adsorbent powders.

[0040] On the other hand, the step of passing a lithium-containing solution through an aluminum-based adsorbent to adsorb lithium onto the aluminum-based adsorbent may include, for example, a reaction comprising the following reaction formula 1.

[0041] [Reaction Formula 1] LiCl (1-x) .Al(OH)3.nH2O + xLiCl → LiCl.Al(OH)3.nH2O + (1-x)LiCl A washing step may be performed after the adsorption step and before the desorption step. The washing step refers to the step of passing the pretreatment solution through the lithium-adsorbent to remove impurities.

[0042] The total dissolved solids (TDS) concentration of the pretreatment solution can range from 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. Here, the total dissolved solids concentration is independent of the type of salt and refers to the concentration including all salts.

[0043] If the total dissolved solids concentration is below the stated range, lithium desorption may occur, potentially leading to reduced lithium recovery and the inability to effectively remove impurities. Furthermore, if the total dissolved solids concentration is above the stated range, salt may instead act as an impurity. In particular, considering that sodium chloride (NaCl), comprising more than 50% by weight of the total dissolved solids, has a solubility of approximately 6.141 mol / L (approximately 358.9 g / L, @25°C), the formation of precipitates upon reaching a saturated solution makes impurity removal difficult and may increase the load on subsequent processes. Therefore, the concentration of total dissolved solids in the pretreatment solution preferably meets the stated range.

[0044] In this case, the pretreatment solution can be a solution containing anions corresponding to the adsorbed lithium. Specifically, the anion can be Cl... -Since the adsorption / desorption of Li in solution by aluminum-based adsorbents can only be achieved when Li exists in the form of LiCl, and other anions may act as impurities during pretreatment, the preferred anion is Cl. - .

[0045] In addition, 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).

[0046] Specifically, the pretreatment solution may be a solution containing one or more of the following: NaCl, KCl, CaCl2, MgCl2, and LiCl.

[0047] Furthermore, the pretreatment solution may contain lithium. By using a lithium-containing pretreatment solution, the influence of other impurities can be reduced, and if the washing solution is mixed with the original brine for further extraction, the loss of lithium will not be excessive. In this case, the lithium concentration in the pretreatment solution can be from 0.05 to 3.0 g / L, 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 is higher than this range, the economics may decrease; if it is lower than this range, it may be difficult to reduce the influence of other impurities.

[0048] The amount of lithium contained in the pretreatment solution after passing through the adsorbent can range from 0.1 to 10.0 wt%, specifically 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%, relative to the amount of lithium present in the adsorbent after the adsorption step.

[0049] This indicates that the pretreatment solution inhibits the desorption of lithium adsorbed on the adsorbent during the washing step.

[0050] After performing the washing step, the step of obtaining the lithium-containing desorption solution is then performed.

[0051] Specifically, a medium (e.g., distilled water or an aqueous solution containing lithium salt) can be passed through the aluminum adsorbent that has adsorbed lithium to obtain a lithium-containing desorbent.

[0052] When the medium is passed through the aluminum adsorbent that has adsorbed lithium, the amount of medium can be 10 to 50 BV, more specifically 20 to 40 BV, based on the bed volume (BV) of the adsorbent column.

[0053] In the total lithium-containing desorbate obtained by passing the medium through the adsorbent, in order to re-adsorb lithium using the adsorbent, most of the lithium adsorbed on the adsorbent must be desorbed so that the lithium concentration in the desorbate after 80% by volume of the desorbate has passed is less than 0.2 g / L, specifically 0.1 g / L or 0.05 g / L. Therefore, it may be necessary to perform the step of passing the medium within the range of the above range of the medium through an aluminum adsorbent that has adsorbed lithium.

[0054] Lithium hydroxide can be recovered from a desorbent with a high lithium concentration obtained via the desorption step, but is not limited thereto. Specifically, the lithium-containing desorbent obtained after the washing step to remove impurities, up to the stage of passing a 10 BV medium, can be used in the process. Preferably, the lithium-containing desorbent obtained up to the stage of passing a 7 BV or 5 BV medium can be used in the process, but this may vary depending on the shape of the desorption curve.

[0055] The amount of lithium obtained in the desorption step can range from 90.0 to 99.9% by weight, specifically from 95.0 to 99.9% by weight, relative to the amount of lithium present in the adsorbent after the adsorption step.

[0056] Without the washing step according to the invention, the lithium loss can range from 10.0 to 50.0% by weight, specifically from 25.0 to 45.0% by weight or 30.0 to 40.0% by weight, relative to the amount of lithium present in the adsorbent after the adsorption step. This lithium loss occurs because lithium-containing desorption solutions with high concentrations of impurities may be difficult to use in lithium recovery processes. Lower concentrations of impurities (salts other than lithium) are preferable. Specifically, in the case of lithium-containing desorption solutions containing impurities (salts other than lithium) of 20 g / L, 15 g / L, or less than 10 g / L, the recovery rate of lithium hydroxide obtained after performing the subsequent process described later may be excellent.

[0057] The step of passing a medium through the aluminum adsorbent containing lithium to obtain a lithium-containing desorbent may include, for example, a reaction comprising the following reaction formula 2.

[0058] [Reaction 2] LiCl·Al(OH)3·nH2O → LiCl (1-x) Al(OH)3·nH2O + xLiCl In one embodiment of the invention, the medium used in the desorption step may be an aqueous solution containing a lithium salt. Specifically, the medium may be an aqueous solution containing lithium chloride. In this case, the lithium concentration in the resulting desorbent may increase. This improvement in lithium concentration in the desorbent can reduce the load on the subsequent concentration process.

[0059] Specifically, the lithium concentration in the medium can range from 0.05 g / L to 1.50 g / L, more specifically from 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 range described above, the lithium (Li) contained in the aluminum adsorbent will be lost, which may damage the LDH (Layered Double Hydroxide) structure. If the concentration is above the range described above, adsorption rather than desorption may occur.

[0060] The lithium concentration in the lithium-containing desorption solution obtained by the method described above can be from 0.1 g / L to 3.0 g / L or from 0.2 g / L to 3.0 g / L, more specifically from 0.8 g / L to 2.5 g / L.

[0061] When the lithium concentration in the desorption solution is high, it means that the amount of water that needs to be removed in the subsequent concentration step is reduced, thus significantly reducing the load on the downstream processes. In this case, the downstream processes can refer to the concentration step.

[0062] According to one embodiment of the lithium adsorption and desorption method, it may further include a step of concentrating all the desorbed solution obtained through the desorption step.

[0063] Specifically, the concentration step may include a concentration process using desorbents obtained through reverse osmosis and electrodialysis. Thus, the target lithium concentration can be determined based on the properties of the intermediate material to be extracted. In addition to the methods described above, if further concentration is required, the lithium concentration can be increased to the desired level through a concentration step using reduced pressure / evaporation.

[0064] Preferred embodiments of the present invention are described below. However, the following embodiments are merely one preferred embodiment of the present invention, and the present invention is not limited to the following embodiments.

[0065] Experimental Example - Confirmation Experiment on Lithium Extraction Inhibition Effect Based on Total Dissolved Solids Concentration First, experiments were conducted to determine the appropriate concentration range of total dissolved solids in the pretreatment solution used in the washing step.

[0066] A brine solution with the components shown in Table 1 was prepared.

[0067] [Table 1] (A) Adsorption step 4 L of brine having the components shown in Table 1 was passed through an adsorbent containing aluminum hydroxide.

[0068] (B) Washing steps Distilled water and sodium chloride aqueous solutions with concentrations ranging from 0.2 to 6.2 mol / L were used as pretreatment solutions. The concentration of lithium present in the washing solution was measured after passing 0.2 L of this pretreatment solution through the solution.

[0069] Example A brine solution with the components shown in Table 1 was prepared.

[0070] (A) Adsorption step The 4L of brine is passed through an adsorbent containing aluminum hydroxide.

[0071] (B) Washing steps Impurities are removed by passing 0.2 L of a 30 g / L (0.513 mol / L) sodium chloride aqueous solution through it.

[0072] (C) Desorption steps Next, 4 L of an aqueous lithium chloride solution is passed through the adsorbent containing lithium to obtain a lithium-containing desorbent.

[0073] At this point, the amount of medium used in one desorption step is defined as 1 bed volume (BV). Specifically, the desorption step is performed to 40 BV using a lithium chloride aqueous solution with a concentration of 0.15 g / L at a temperature of 40 °C and a flow rate of 30 mL / min.

[0074] Comparative example A brine solution with the components shown in Table 2 was prepared.

[0075] [Table 2] For the comparative example, brine having the components shown in Table 2 was used, and the washing steps in Example 1 were not performed. Otherwise, lithium adsorption and desorption were performed in the same manner as in Example 1.

[0076] Compared to the brine used in the examples, the brine used in the comparative example has a higher impurity content in terms of other components (Ca, Na, K), including Li. This component corresponds to the composition of geothermal brine, which is one of the unconventional resources.

[0077] When adsorption is performed using saline solution containing this component, a relatively large amount of impurities (ions other than lithium) will adhere to the surface of the adsorbent. Specifically, unlike lithium, these impurities are not adsorbed within the crystal lattice structure during adsorption; instead, they exist on the surface of the adsorbent.

[0078] If the desorption process is carried out directly without a washing step, as mentioned above, impurities present on the surface of the adsorbent will enter the medium when it is added. In other words, due to the presence of impurities in the medium, the concentration of total dissolved solids may temporarily reach above 0.5 mol / L.

[0079] In other words, this confirms whether there is a phenomenon of delayed lithium (Li) desorption caused by the total dissolved solids concentration resulting from impurities dissolving from the adsorbent surface and entering the medium.

[0080] The experimental results confirmed by the above embodiments and comparative examples are as follows.

[0081] Figure 1 This data pertains to the amount of lithium desorption during the washing step according to an embodiment of the present invention, which varies with the total dissolved solids concentration in the pretreatment solution.

[0082] Reference Figure 1 As the total dissolved solids (TDS) concentration in the stripping solution decreases, more lithium (Li) adsorbed on the adsorbent will desorb, resulting in a high concentration of lithium in the washing solution. Specifically, when the TDS concentration is below 0.5 mol / L, it can be confirmed that the lithium concentration in the washing solution is above 0.04 mol / L, leading to lithium loss.

[0083] Specifically, from Figure 6 It was confirmed that for initial desorption solutions with extremely high calcium concentrations (below 0.75 BV) of 30 g / L, the desorption of some lithium was delayed. Therefore, it can be predicted that even if the lithium-containing solution used in the adsorption step contains a large number of impurities, resulting in a high concentration of impurities on the surface of the adsorbent, the amount of lithium obtained in the subsequent desorption step can reach 90.0% to 99.9% by weight, even if the total dissolved solids concentration of the pretreatment solution in the washing step is 0.5 to 1.0 mol / L.

[0084] Figure 2 These are lithium concentration data varying with the amount of adsorbent solution passing through the washing and desorption steps according to an embodiment of the present invention.

[0085] exist Figure 2 In the figure, the gray area represents the data for washing with the pretreatment solution. The area of ​​the shown area is 13.961 g, which represents the amount of lithium desorbed during the washing step.

[0086] Figure 3 These are lithium concentration data as a function of the amount of solution passing through the adsorbent during the lithium desorption step according to a comparative example of the present invention.

[0087] exist Figure 3In the figure, the gray area represents the data for the initial desorption stage. The area of ​​the shown area is 87.135 g, which represents the amount of lithium desorbed in the initial desorption stage.

[0088] Figure 4 These are sodium concentration data as a function of the amount of solution passing through the adsorbent during the lithium desorption step according to a comparative example of the present invention.

[0089] exist Figure 4 In the figure, the gray area represents the data of the initial desorption stage. The area of ​​the shown interval is 4142.577 g, which represents the amount of sodium desorbed in the initial desorption stage.

[0090] If passed Figure 3 and Figure 4 It has been confirmed that the desorbent obtained in the initial desorption stage is difficult to use due to its high impurity content, and the desorbent also contains lithium. As lithium is lost, the lithium recovery rate will decrease.

[0091] In addition, such as through Figure 2 and Figure 3 It has been confirmed that, with impurities removed in the initial washing step, lithium recovery can be further improved in the subsequent desorption step.

[0092] Figure 5 These are lithium and calcium concentration data varying with BV during the washing and desorption steps according to an embodiment of the present invention. Figure 6 These are lithium and calcium concentration data as a function of BV during the lithium desorption step according to a comparative example of the present invention.

[0093] By comparison Figure 5 and Figure 6 It can be confirmed that, regardless of whether a washing step is performed, most of the calcium (Ca) impurities are desorbed within 2 BV; as for lithium (Li), in the examples, the amount of lithium desorbed within 2 BV is 32.8 mg, accounting for 2% of the total lithium amount, relative to the total amount of desorbent up to 30 BV; while in the comparative examples, the amount of lithium desorbed within 2 BV is 174.2 mg, accounting for 32% of the total lithium amount, relative to the total amount of desorbent up to 30 BV.

[0094] Specifically, refer to Figure 6 It can be confirmed that, without the washing step according to this embodiment, for an initial desorption solution with an extremely high calcium concentration of less than 0.75 BV of 30 g / L, the desorption of some lithium is delayed, but the total amount of dissolved solids decreases subsequently, and lithium is desorbed at a high concentration while the impurities are still present in a high concentration range, making it difficult to selectively separate from the impurities.

[0095] In other words, when the washing step according to this embodiment is not included, it can be confirmed that lithium will desorb along with a high content of impurities during the initial desorption stage, resulting in a decrease in lithium recovery rate.

[0096] This invention is not limited to the embodiments described above, and can be prepared in various different ways. Those skilled in the art should understand that this invention can be implemented in other specific ways without changing the technical concept or essential features of the invention. Therefore, it should be understood that the above embodiments are exemplary in all respects and not restrictive.

Claims

1. A method for lithium adsorption and desorption, comprising: The adsorption step involves passing a lithium-containing solution through an adsorbent to obtain an adsorbent with adsorbed lithium. The washing step involves passing the pretreatment solution through the lithium-adsorbent to remove impurities; and The desorption step involves passing the medium through the adsorbent containing lithium to obtain a lithium-containing desorbed solution. The pretreatment solution inhibits the desorption of lithium adsorbed on the adsorbent during the washing step.

2. The lithium adsorption and desorption method according to claim 1, wherein, The total dissolved solids concentration of the pretreatment solution ranges from 0.5 to 3.0 mol / L.

3. The lithium adsorption and desorption method according to claim 1, wherein, The pretreatment solution is a solution containing anions corresponding to the adsorbed lithium.

4. The lithium adsorption and desorption method according to claim 1, wherein, The pretreatment solution is a solution containing one or more salts selected from the group consisting of sodium, potassium, calcium, magnesium and lithium.

5. The lithium adsorption and desorption method according to claim 1, wherein, The pretreatment solution is a solution containing one or more of the following: NaCl, KCl, CaCl2, MgCl2, and LiCl.

6. The lithium adsorption and desorption method according to claim 1, wherein, The pretreatment solution is a solution containing lithium at a concentration of 0.05 to 3.0 g / L in the total pretreatment solution.

7. The lithium adsorption and desorption method according to claim 1, wherein, The lithium concentration of the lithium-containing solution in the adsorption step is from 0.03 to 2.0 g / L.

8. The lithium adsorption and desorption method according to claim 1, wherein, The lithium concentration of the medium used in the desorption step is from 0.05 to 1.50 g / L.

9. The lithium adsorption and desorption method according to claim 1, wherein, The amount of lithium present in the adsorbent after the adsorption step. The amount of lithium contained in the pretreatment solution after the washing step ranges from 0.1 to 10.0 wt%.

10. The lithium adsorption and desorption method according to claim 1, wherein, The amount of lithium present in the adsorbent after the adsorption step. The amount of lithium obtained in the desorption step ranges from 90.0 to 99.9 by weight.

11. The lithium adsorption and desorption method according to claim 1, wherein, The adsorbent is an aluminum-based adsorbent.

12. The lithium adsorption and desorption method according to claim 1, further comprising: A step of concentrating all the desorbed solution obtained through the desorption step.

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