A lithium extraction device and method

Abstract

The application discloses a lithium extraction device and a lithium extraction method, and belongs to the technical field of lithium extraction. The lithium extraction device can replace or adjust the ion membrane according to needs without replacing the electrode, so that the ion membrane can be used for multiple adsorption and desorption processes. In the process, the ion membrane does not need to be cleaned, the cleaning water is saved, the energy consumption and the cost are greatly saved, and in the process, the electrode for desorption and embedding does not need to be replaced back and forth, so that the lithium extraction efficiency is improved.

Description

Technical Field

[0001] This disclosure relates to the field of lithium extraction technology, and more specifically, to a lithium extraction apparatus and a lithium extraction method. Background Technology

[0002] The global energy transformation and transition is an inevitable trend, with the rapid development of the electric vehicle industry being a crucial component, leading to a strong global demand for lithium-ion batteries. Lithium possesses numerous excellent physicochemical properties, and its functions and applications are extremely broad, earning it the title of "the energy metal that drives world progress." Initially, lithium products were primarily used in the military. However, with the rapid development of industries such as new energy, metallurgy, aerospace, and glass manufacturing, the demand for lithium has been increasing year by year, and the development of lithium extraction technologies has received increasing attention.

[0003] However, existing lithium extraction methods suffer from problems such as high water consumption, high cost, high energy consumption, long processing time, and low lithium extraction efficiency.

[0004] In view of this, this disclosure is hereby made. Summary of the Invention

[0005] The purpose of this disclosure includes providing a lithium extraction apparatus and a lithium extraction method to improve or solve at least one of the above-mentioned technical problems.

[0006] This disclosure can be implemented as follows:

[0007] In a first aspect, this disclosure provides a lithium extraction apparatus, which includes a reaction tank, a first electrode, a second electrode, and a reaction liquid container;

[0008] The reaction tank has a first tank area, a reaction liquid containing area and a second tank area; a first electrode and a second electrode are respectively disposed in the first tank area and the second tank area; the reaction liquid containing component is movably disposed in the reaction liquid containing area; both the first electrode and the second electrode are used to connect to a power source.

[0009] The reaction liquid container includes a first container for holding the lithium-containing solution to be treated and a second container for holding the recovery liquid;

[0010] The reaction solution containment area is selectively provided with a first containment or a second containment; the first containment has an ion membrane, which allows lithium ions and anions in the lithium-containing solution to be treated to pass through under energized conditions and be adsorbed onto the first electrode and the second electrode, respectively; the second containment also has an ion membrane, which allows lithium ions and anions desorbed from the first electrode and the second electrode to pass through and enter the recovery solution.

[0011] Alternatively, the first and second containers are independently disposed in the reaction liquid containing area; the first container has an ion membrane for lithium ions in the lithium-containing solution to be treated to pass through and be adsorbed onto the lithium-poor or low-lithium state first or second electrode under energized conditions; the second container also has an ion membrane for lithium ions applied to the lithium-rich second or first electrode to pass through and enter the recovery liquid under energized conditions.

[0012] In an optional embodiment, when the reaction liquid containing area is selectively provided with a first container or a second container, both the first container and the second container are extractable.

[0013] In an optional embodiment, when the first container and the second container are jointly disposed in the reaction liquid containing area, the first container and the second container are either extractable or rotatable.

[0014] In an optional embodiment, when the reaction liquid containing area is selectively provided with a first containing element or a second containing element, the first electrode is a lithium iron phosphate electrode or a lithium manganese oxide electrode, and the second electrode is an inert electrode.

[0015] In an optional embodiment, the inert electrode includes a carbon-containing electrode, a platinum-containing electrode, or a gold-containing electrode.

[0016] In an optional embodiment, when the first and second containers are both disposed in the reaction liquid containing area, the first electrode and the second electrode are both lithium iron phosphate electrodes or both are lithium manganese oxide electrodes.

[0017] In an optional embodiment, the surfaces of the first electrode and / or the second electrode have a gel-like electrolyte.

[0018] In optional embodiments, the ion exchange membrane includes a sulfonic acid-based ion exchange membrane, a carboxylic acid-based ion exchange membrane, or a phosphate-based ion exchange membrane.

[0019] In an optional embodiment, the lithium extraction apparatus further includes a power source for connection to the first electrode and the second electrode.

[0020] In an optional embodiment, the lithium-containing solution to be treated includes at least one of brine, seawater, waste battery leachate, lithium precipitation mother liquor, and lithium extraction leachate from ore.

[0021] In an optional embodiment, the recovered liquid includes at least one of sodium chloride solution, potassium chloride solution, ammonium chloride solution, sodium sulfate solution, potassium sulfate solution, sodium nitrate solution, and potassium nitrate solution.

[0022] Secondly, this disclosure provides a lithium extraction method, which uses the lithium extraction apparatus of any of the foregoing embodiments to perform lithium extraction processing.

[0023] In an optional embodiment, when the reaction liquid containing area is selectively provided with a first containing member or a second containing member;

[0024] The lithium extraction process includes:

[0025] Electroadsorption process: A first container containing a lithium-containing solution to be treated is placed in the reaction liquid containing area of ​​the reaction tank. The first electrode and the second electrode are connected to the negative and positive terminals of the power supply, respectively. Lithium ions in the lithium-containing solution to be treated pass through the ion membrane of the first container and are adsorbed onto the first electrode, and anions in the lithium-containing solution to be treated pass through the ion membrane of the first container and are adsorbed onto the second electrode.

[0026] Electrodesorption process: Remove the first container containing the remaining solution, place the second container containing the recovery solution into the reaction solution containing area, connect the first electrode and the second electrode to the positive and negative terminals of the power supply respectively, so that the lithium ions desorbed by the oxidation reaction of the first electrode enter the recovery solution through the ion membrane of the second container, and the anions desorbed by the reduction reaction of the second electrode enter the recovery solution through the ion membrane of the second container.

[0027] In an optional embodiment, the voltage applied during the electroadsorption process is 1.0V-1.2V.

[0028] In an optional implementation, the voltage applied during the electrodesorption process is 1.0V-1.2V.

[0029] In an optional implementation, the lithium extraction process includes multiple alternating electro-adsorption and electro-desorption processes.

[0030] In an optional embodiment, when the first container and the second container are both disposed in the reaction liquid containing area;

[0031] The lithium extraction process includes process A: a first container containing a lithium-containing solution to be treated and a second container containing a recovery liquid are placed in the reaction liquid containing area of ​​the reaction tank, with the first container facing the lithium-poor first electrode and the second container facing the lithium-rich second electrode; the first electrode and the second electrode are connected to the negative and positive terminals of the power supply, respectively, so that lithium ions in the lithium-containing solution to be treated pass through the ion membrane of the first container and are adsorbed onto the lithium-poor first electrode, and lithium ions desorbed from the lithium-rich second electrode pass through the ion membrane of the second container into the recovery liquid.

[0032] In an optional embodiment, the lithium extraction process further includes process B: swapping the positions of the first container and the second container so that the first container faces the lithium-poor state second electrode and the second container faces the lithium-rich state first electrode; connecting the first electrode and the second electrode to the positive and negative terminals of a power supply, respectively, so that lithium ions in the lithium-containing solution to be treated pass through the ion membrane of the first container and are adsorbed onto the lithium-poor state second electrode, and so that lithium ions desorbed from the lithium-rich state first electrode pass through the ion membrane of the second container into the recovery solution.

[0033] In an optional implementation, the voltage applied during the lithium extraction process is 1.0V-1.2V.

[0034] In an optional implementation, the lithium extraction process includes multiple alternating processes A and B.

[0035] This disclosure, by setting a movable ion exchange membrane, allows for replacement or adjustment of the ion exchange membrane as needed without changing the electrode, thereby enabling multiple adsorption and desorption processes. During this process, there is no need to clean the ion exchange membrane, saving cleaning water, greatly reducing energy consumption and costs. Furthermore, the process does not require repeated replacement of the insertion / extraction electrode, thus improving lithium extraction efficiency. Attached Figure Description

[0036] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this disclosure and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 A schematic diagram of the structure of the first lithium extraction device provided in this disclosure in its first state;

[0038] Figure 2 A schematic diagram of the structure of the first lithium extraction device provided in this disclosure in a second state;

[0039] Figure 3 This is a schematic diagram of the structure of the second lithium extraction device provided in this disclosure in its first state;

[0040] Figure 4 This is a schematic diagram of the structure of the second lithium extraction device provided in this disclosure in a second state;

[0041] Figure 5 A schematic diagram of the lithium extraction apparatus provided in Comparative Example 1 of this disclosure;

[0042] Figure 6 A schematic diagram of the lithium extraction device provided in Comparative Example 2 of this disclosure in its first state;

[0043] Figure 7 This is a schematic diagram of the lithium extraction apparatus provided in Comparative Example 2 of this disclosure in its second state.

[0044] Icons: 10-Reaction tank; 11-First tank area; 12-Reaction solution containment area; 13-Second tank area; 21-First electrode; 22-Second electrode; 23-Third electrode; 24-Fourth electrode; 31-First containment; 32-Second containment; 33-Ion membrane; 34-Separator; 40-Power supply; 51-Lithium-containing solution to be treated; 52-Recovery solution. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions in the embodiments of this disclosure will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0046] The lithium extraction apparatus and method provided in this disclosure will be described in detail below.

[0047] Please refer to the above as well. Figures 1 to 4 The present disclosure proposes a lithium extraction device, which includes a reaction tank 10, a first electrode 21, a second electrode 22, and a reaction liquid container.

[0048] The reaction tank 10 has a first tank area 11, a reaction liquid containing area 12, and a second tank area 13; a first electrode 21 and a second electrode 22 are respectively disposed in the first tank area 11 and the second tank area 13; the reaction liquid containing component is movably disposed in the reaction liquid containing area 12 (for example, it may include a rotating or detachable type); the first electrode 21 and the second electrode 22 are both used to connect to the power supply 40.

[0049] The reaction liquid container includes a first container 31 for holding the lithium-containing solution 51 to be treated and a second container 32 for holding the recovery liquid 52.

[0050] Please refer to Figure 1 and Figure 2The reaction solution containing zone 12 can be selectively equipped with a first containing element 31 or a second containing element 32 according to different lithium extraction processes or stages. The first containing element 31 has an ion-exchange membrane 33, allowing lithium ions and anions in the lithium-containing solution 51 to pass through and be adsorbed onto the first electrode 21 and the second electrode 22 respectively under energized conditions. The second containing element 32 also has an ion-exchange membrane 33, allowing lithium ions and anions desorbed from the first electrode 21 and the second electrode 22 to pass through and enter the recovery solution 52. In this manner, the first containing element 31 can be placed in the reaction solution containing zone 12 for the electro-adsorption process, and the first containing element 31 can be removed from the reaction solution containing zone 12 and the second containing element 32 can be placed in the reaction solution containing zone 12 when the electro-desorption process is required.

[0051] Please refer to Figure 3 and Figure 4 The first container 31 and the second container 32 can also be independently disposed in the reaction liquid containing area 12. The first container 31 has an ion membrane 33 for lithium ions in the lithium-containing solution 51 to be treated to pass through and be adsorbed onto the lithium-poor or low-lithium state first electrode 21 or second electrode 22 under energized conditions. The second container 32 also has an ion membrane 33 for lithium ions applied to the lithium-rich state second electrode 22 or first electrode 21 to pass through and enter the recovery liquid 52 under energized conditions. In this manner, the reaction liquid containers can be directly rotated within the reaction liquid containing area 12 to interchange the positions of the ion membranes 33 of each container; alternatively, the reaction liquid containers can be removed as a whole, rotated to interchange the positions of the ion membranes 33 of each container, and then placed back into the reaction liquid containing area 12 accordingly.

[0052] In this disclosure, "lithium-rich state" and "lithium-poor state" are relative concepts, that is, the lithium content corresponding to "lithium-rich state" is higher than that of "lithium-poor state".

[0053] It should be noted that some traditional lithium extraction devices require replacing the lithium-containing solution with the recovery solution 52 after a single lithium extraction. Before replacing the recovery solution 52, a large amount of deionized water is needed to clean the ion exchange membrane 33 or the lithium extraction tank, which makes the lithium extraction process time-consuming, inefficient for continuous operation, consumes a lot of water, and pollutes the environment. Other lithium extraction devices are integrated lithium insertion and delithiation devices. After lithium insertion and delithiation are completed, the lithium insertion electrode and the delithiation electrode need to be replaced, and then reverse power is applied to perform lithium insertion and delithiation. This process is cumbersome and the electrode replacement is difficult, resulting in low lithium extraction efficiency.

[0054] This disclosure, by setting a movable ion exchange membrane 33, allows the ion exchange membrane 33 to be replaced or adjusted as needed without replacing the electrodes, thereby performing multiple adsorption and desorption processes. During this process, there is no need to clean the ion exchange membrane 33, saving cleaning water and greatly saving energy consumption and cost (in traditional lithium extraction systems, more than 70% of the energy consumption comes from cleaning the ion exchange membrane 33). Moreover, during this process, there is no need to replace the insertion / extraction electrodes back and forth, thus improving lithium extraction efficiency.

[0055] In this disclosure, the first tank area 11, the reaction liquid containing area 12, and the second tank area 13 are arranged sequentially. For example, using... Figures 1 to 4 As shown in the orientation diagram, the first tank area 11, the reaction liquid containing area 12, and the second tank area 13 are arranged sequentially from left to right.

[0056] When the reaction solution containing area 12 is selectively provided with a first containing element 31 or a second containing element 32, both the first containing element 31 and the second containing element 32 are removable, and their specific shapes can be, for example, cylindrical, frame-shaped, or box-shaped. That is, when it is necessary to change the type of solution in the reaction solution containing area 12, the unwanted first containing element 31 or second containing element 32 can be directly removed, and then the second containing element 32 or first containing element 31 can be placed in as needed. For example, when electroadsorption is required (such as... Figure 1 ), and place the first container 31 containing the lithium-containing solution 51 to be treated into the reaction solution containing area 12 (or the first container 31 can be placed first, and then the lithium-containing solution 51 to be treated can be added into the first container 31); when electro-desorption is required (such as Figure 2 Remove the first container 31 and place the second container 32 containing the recovery liquid 52 into the reaction liquid containing area 12 (or you can place the second container 32 first and then fill it with the recovery liquid 52); when electroadsorption is required again (such as... Figure 1 Remove the second container 32 and place the first container 31 containing a new lithium-containing solution 51 to be treated into the reaction liquid containing area 12 (or you can first place the first container 31 and then fill it with the new lithium-containing solution 51 to be treated). This method eliminates the need to rinse the first container 31 and the second container 32 during use, avoiding the problem of cleaning the containers when the liquid in the reaction liquid containing area 12 changes, as is common in existing devices. Furthermore, it eliminates the need to replace the first electrode 21 and the second electrode 22.

[0057] When the first container 31 and the second container 32 are both disposed in the reaction liquid containing area 12, the first container 31 and the second container 32 are either removable or rotatable, and their specific shapes can be, for example, cylindrical, frame-shaped, or box-shaped. If the first container 31 and the second container 32 are removable, when it is necessary to change the lithium-containing solution 51 to be treated and the recovery liquid 52, the unwanted container can be removed from the corresponding position and the desired container can be placed in; or, the first container 31 and the second container 32 can be removed as a whole, rotated, and then placed back into the reaction liquid containing area 12 to interchange the positions of the ion exchange membranes 33 of each container. If the first container 31 and the second container 32 are rotatable, the positions of the lithium-containing solution 51 to be treated and the recovery liquid 52 can be changed by rotation to interchange the positions of the ion exchange membranes 33 of each container. This method also avoids the problem of rinsing the first container 31 and the second container 32 during use, and also eliminates the need to replace the first electrode 21 and the second electrode 22.

[0058] For reference, when the reaction liquid containing zone 12 is selectively provided with a first containing element 31 or a second containing element 32, the first electrode 21 used in the lithium extraction device can be, exemplarily, a lithium iron phosphate electrode or a lithium manganese oxide electrode, and the second electrode 22 can be, exemplarily, an inert electrode, such as a carbon-containing electrode, a platinum-containing electrode, or a gold-containing electrode. The first electrode 21 is in a lithium-poor state at the beginning of the electro-adsorption process, and gradually changes from a lithium-poor state to a lithium-rich state as the electro-adsorption process continues. Similarly, the first electrode 21 is in a lithium-rich state at the beginning of the electro-desorption process, and gradually changes from a lithium-rich state to a lithium-poor state as the electro-desorption process continues. The second electrode 22 is used to adsorb anions in the lithium-containing solution 51 to be treated during the electro-adsorption process and to release anions into the recovery liquid 52 during the electro-desorption process.

[0059] When the first container 31 and the second container 32 are both disposed in the reaction liquid containing area 12, the first electrode 21 and the second electrode 22 used in the lithium extraction device can be, for example, lithium iron phosphate electrodes or lithium manganese oxide electrodes. For example, the first electrode 21 is in a lithium-poor state at the beginning of the lithium extraction process, and the second electrode 22 is in a lithium-rich state at the beginning of the lithium extraction process. As the lithium extraction process continues, the first electrode 21 gradually changes from a lithium-poor state to a lithium-rich state by adsorbing lithium ions in the lithium-containing solution 51 to be treated, while the second electrode 22 gradually changes from a lithium-rich state to a lithium-poor state by desorbing lithium ions into the recovery liquid 52. When the positions of the first container 31 and the second container 32 are exchanged, the first electrode 21 gradually changes from a lithium-rich state to a lithium-poor state by desorbing lithium ions into the recovery liquid 52, and correspondingly, the second electrode 22 gradually changes from a lithium-poor state to a lithium-rich state by adsorbing lithium ions in the lithium-containing solution 51 to be treated.

[0060] In some embodiments, the surfaces of the first electrode 21 and / or the second electrode 22 may have a gel-like electrolyte. By providing a gel-like electrolyte on the surface of the electrodes, the electrolyte can enter the pores of the electrode plate, which helps to increase the effective contact area and improve the lithium-ion insertion / extraction rate.

[0061] In some embodiments, when the reaction liquid containing region 12 is selectively provided with a first containing member 31 or a second containing member 32, both the first containing member 31 and the second containing member 32 can be formed by an ion membrane 33.

[0062] In some embodiments, when the first container 31 and the second container 32 are both disposed in the reaction liquid containing area 12, the first container 31 and the second container 32 can be separate or integrated. If they are separate, both the first container 31 and the second container 32 can be formed by an ion exchange membrane 33; if they are integrated, the first container 31 and the second container 32 are separated by a separator 34, and the remaining positions can be formed by an ion exchange membrane 33. Taking the example where both the first container 31 and the second container 32 are cuboid in shape, each of the first container 31 and the second container 32 independently has an ion exchange membrane 33 that cooperates with the first electrode 21 or the second electrode 22 at different processing stages. The aforementioned positional transformation of the first container 31 and the second container 32 essentially involves swapping the positions of the ion exchange membrane 33 that cooperates with the first electrode 21 and the ion exchange membrane 33 that cooperates with the second electrode 22.

[0063] In this disclosure, the ion exchange membrane 33 of each containment may include a sulfonic acid-based ion exchange membrane, a carboxylic acid-based ion exchange membrane, or a phosphate-based ion exchange membrane. Specifically, it may include, for example, a lithium-ion selectively permeable membrane.

[0064] Furthermore, the lithium extraction device also includes a power supply 40 for connecting to the first electrode 21 and the second electrode 22.

[0065] For reference, the lithium-containing solution 51 to be treated as used in this disclosure may, by way of example, include at least one of brine, seawater, waste battery leachate, lithium precipitation mother liquor, and lithium extraction leachate from ore. The recovery solution 52 may, by way of example, include at least one of sodium chloride solution, potassium chloride solution, ammonium chloride solution, sodium sulfate solution, potassium sulfate solution, sodium nitrate solution, and potassium nitrate solution.

[0066] As mentioned above, the lithium extraction device provided in this disclosure has a relatively simple structure and is easy to operate. On the one hand, it can avoid the tedious replacement of lithium insertion and extraction electrodes in the prior art, and on the other hand, it can avoid using a large amount of deionized water to clean the ion membrane 33 during the lithium extraction process. This improves the lithium extraction efficiency while reducing environmental pollution.

[0067] Accordingly, this disclosure also provides a lithium extraction method, which uses the above-mentioned lithium extraction apparatus for lithium extraction processing.

[0068] When the reaction liquid containing area 12 is selectively provided with a first containing element 31 or a second containing element 32, the lithium extraction process may include an electro-adsorption process and an electro-desorption process.

[0069] The electroadsorption process can be referenced (e.g.) Figure 1 ): A first container 31 containing a lithium-containing solution 51 to be treated is placed in the reaction liquid containing area 12 of the reaction tank 10 (or the first container 31 can be placed first and then the lithium-containing solution 51 to be treated is added to the first container 31). The first electrode 21 and the second electrode 22 are placed in the first tank area 11 and the second tank area 13 respectively. The first electrode 21 and the second electrode 22 are connected to the negative terminal and the positive terminal of the power supply 40 respectively, so that the lithium ions in the lithium-containing solution 51 to be treated pass through the ion membrane 33 of the first container 31 and are adsorbed onto the first electrode 21, and the anions in the lithium-containing solution 51 to be treated pass through the ion membrane 33 of the first container 31 and are adsorbed onto the second electrode 22.

[0070] The electrodesorption process can be referenced (e.g.) Figure 2 ): Remove the first container 31 containing the remaining solution, and place the second container 32 containing the recovery solution 52 into the reaction solution containing area 12 (or place the second container 32 first, and then add the recovery solution 52 into the second container 32). Connect the first electrode 21 and the second electrode 22 to the positive and negative terminals of the power supply 40, respectively, so that the lithium ions desorbed by the oxidation reaction of the first electrode 21 enter the recovery solution 52 through the ion membrane 33 of the second container 32, and so that the anions desorbed by the reduction reaction of the second electrode 22 enter the recovery solution 52 through the ion membrane 33 of the second container 32.

[0071] In some embodiments, the voltage applied during the electroadsorption process can be 1.0V-1.2V, such as 1.0V, 1.05V, 1.1V, 1.15V, or 1.2V. The electroadsorption process can continue, for example, until the lithium ion concentration in the lithium-containing solution to be treated does not exceed a preset concentration, which can be adjusted and set according to actual conditions.

[0072] Similarly, the voltage applied during the electrodesorption process can also be 1.0V-1.2V, such as 1.0V, 1.05V, 1.1V, 1.15V, or 1.2V. The electrodesorption process can continue, for example, until the lithium ion concentration in the recovery solution 52 is not lower than a preset concentration, which can also be adjusted and set according to the actual situation.

[0073] In practice, the lithium extraction process may include multiple alternating electro-adsorption and electro-desorption processes as needed.

[0074] When the first container 31 and the second container 32 are both disposed in the reaction liquid containing area 12, the lithium extraction process may include process A and process B.

[0075] Process A can be referenced (e.g.) Figure 3 ): A first container 31 containing a lithium-containing solution 51 to be treated (or the first container 31 can be placed first, and then the lithium-containing solution 51 to be treated can be added to the first container 31) and a second container 32 containing a recovery liquid 52 (or the second container 32 can be placed first, and then the recovery liquid 52 can be added to the second container 32) are placed in the reaction liquid containing area 12 of the reaction tank 10. A lithium-poor state first electrode 21 and a lithium-rich state second electrode 22 are placed in the first tank area 11 and the second tank area 13, respectively, with the first container 31 facing the first electrode 21 and the second container 32 facing the second electrode 22. The first electrode 21 and the second electrode 22 are connected to the negative terminal and the positive terminal of the power supply 40, respectively, so that the lithium ions in the lithium-containing solution 51 to be treated pass through the ion membrane 33 of the first container 31 and are adsorbed onto the lithium-poor state first electrode 21, and the lithium ions desorbed from the lithium-rich state second electrode 22 pass through the ion membrane 33 of the second container 32 and enter the recovery liquid 52. That is, as process A continues, the first electrode 21 gradually changes from a lithium-poor state to a lithium-rich state, while the second electrode 22 gradually changes from a lithium-rich state to a lithium-poor state.

[0076] Process B can be referenced (e.g.) Figure 4 In process B, the positions of the first container 31 and the second container 32 are swapped, so that the first container 31 faces the lithium-poor second electrode 22 and the second container 32 faces the lithium-rich first electrode 21. The first electrode 21 and the second electrode 22 are connected to the positive and negative terminals of the power supply 40, respectively. This allows lithium ions in the lithium-containing solution 51 to pass through the ion exchange membrane 33 of the first container 31 and be adsorbed onto the lithium-poor second electrode 22, while lithium ions desorbed from the lithium-rich first electrode 21 pass through the ion exchange membrane 33 of the second container 32 and enter the recovery solution 52. In other words, as process B progresses, the first electrode 21 gradually changes from a lithium-rich state to a lithium-poor state, while the second electrode 22 gradually changes from a lithium-poor state to a lithium-rich state.

[0077] Similarly, the voltage applied during the lithium extraction process can also be 1.0V-1.2V, such as 1.0V, 1.05V, 1.1V, 1.15V or 1.2V.

[0078] In practice, the lithium extraction process may include multiple alternating processes A and B, as needed.

[0079] It should be noted that in this disclosure, the lithium-containing solution after delithiation can be selectively recycled (when the lithium ion content in the lithium-containing solution after delithiation is too low, a new lithium-containing solution is replaced), and the recovery liquid 52 after absorbing lithium ions can also be selectively recycled (when the recovery liquid 52 after absorbing lithium ions reaches saturation, a new recovery liquid 52 is replaced to absorb lithium ions).

[0080] As mentioned above, the lithium extraction method provided in this disclosure is simple to operate, has high lithium extraction efficiency, and the whole process has low energy consumption and low carbon emissions, which is in line with the concept of low carbon and environmental protection.

[0081] The features and performance of this disclosure will be further described in detail below with reference to embodiments.

[0082] Example 1

[0083] Please refer to Figure 1 and Figure 2 This embodiment provides a lithium extraction device, which includes a reaction tank 10, a first electrode 21 (lithium iron phosphate electrode), a second electrode 22 (carbon-containing electrode), a reaction liquid container, and a power supply 40.

[0084] The reaction tank 10 has a first tank area 11, a reaction liquid containing area 12, and a second tank area 13 arranged sequentially from left to right. A first electrode 21 and a second electrode 22 are respectively disposed in the first tank area 11 and the second tank area 13. The reaction liquid containing components include a box-shaped first containing component 31 containing a lithium-containing solution 51 to be treated and a box-shaped second containing component 32 containing a recovery liquid 52. Both the first containing component 31 and the second containing component 32 are selectively disposed in the reaction liquid containing area 12 by extraction. The first containing component 31 is formed of an ion-exchange membrane 33, through which lithium ions and anions in the lithium-containing solution 51 to be treated can pass under energized conditions and be adsorbed onto the first electrode 21 and the second electrode 22, respectively. The second containing component 32 is formed of an ion-exchange membrane 33, through which lithium ions and anions desorbed from the first electrode 21 and the second electrode 22 can pass under energized conditions and enter the recovery liquid 52. Both the first electrode 21 and the second electrode 22 are used to connect to a power supply 40.

[0085] The surfaces of both the first electrode 21 and the second electrode 22 are coated with a gel-like electrolyte. The ion-exchange membrane 33 in each of the aforementioned containers is a lithium-ion selectively permeable membrane (purchased from Shanghai Luton Optoelectronics Technology Co., Ltd.). The lithium-containing solution 51 to be treated is a lithium-containing brine (lithium ion concentration of 0.45 g / L). The recovery solution 52 is a sodium chloride solution (concentration of 0.8 mol / L).

[0086] The lithium extraction methods corresponding to the above-mentioned lithium extraction equipment are as follows:

[0087] Electroadsorption processes (such as) Figure 1The first electrode 21 and the second electrode 22 are connected to the negative and positive terminals of the power supply 40, respectively. A constant voltage of 1.2V is applied, causing lithium ions in the lithium-containing brine to be adsorbed onto the lithium-depleted lithium iron phosphate electrode through the ion membrane 33 of the first container 31, and causing anions in the lithium-containing brine to be adsorbed onto the slurry of the carbon-containing electrode through the ion membrane 33 of the first container 31. The lithium-containing brine becomes delithiated brine through the electro-adsorption process. The delithiated brine is stored and reused or discharged as waste, and the first container 31 is reused for the next electro-adsorption process.

[0088] Electrodesorption process (e.g.) Figure 2 The first container 31 is removed, and a second container 32 containing sodium chloride solution is placed in the reaction solution containing area 12. The first electrode 21 and the second electrode 22 are connected to the positive and negative terminals of the power supply 40, respectively. A constant voltage of 1.2V is applied, causing lithium ions desorbed by the oxidation reaction of the first electrode 21 to pass through the ion membrane 33 of the second container 32 into the recovery solution 52, and causing anions desorbed by the reduction reaction of the second electrode 22 to pass through the ion membrane 33 of the second container 32 into the recovery solution 52. The recovery solution 52 collects the lithium ions and anions desorbed by the first container 31 and the second container 32 to form a lithium-rich recovery solution 52. The lithium-rich recovery solution 52 can be reused or stored, and the second container 32 can be reused for the next electrodesorption process.

[0089] The electro-adsorption and electro-desorption processes described above are operated alternately. During the process, the lithium ion concentration of the lithium-containing brine decreases successively. As the lithium ion concentration decreases, the lithium-containing brine is replaced with fresh brine. Lithium ions continuously accumulate in the lithium-rich recovery solution 52. The recovery solution 52 is replaced with fresh recovery solution according to the change in lithium ion concentration to prevent it from becoming saturated and unable to absorb lithium ions, thus continuously obtaining lithium-rich recovery solution 52. During the process, the first container 31 and the second container 32 in the reaction containment zone are also replaced according to the corresponding electro-adsorption and electro-deintercalation processes.

[0090] Example 2

[0091] Please refer to Figure 3 and Figure 4 This embodiment provides a lithium extraction device, which includes a reaction tank 10, a first electrode 21 (lithium iron phosphate electrode), a second electrode 22 (lithium iron phosphate electrode), a reaction liquid container, and a power supply 40.

[0092] The reaction tank 10 has a first tank area 11, a reaction liquid containing area 12, and a second tank area 13 arranged sequentially from left to right. A first electrode 21 and a second electrode 22 are respectively disposed in the first tank area 11 and the second tank area 13. The reaction liquid containing component includes a cylindrical first containing component 31 containing a lithium-containing solution 51 to be treated and a cylindrical second containing component 32 containing a recovery liquid 52. The first containing component 31 and the second containing component 32 are integrally formed and rotatable within the reaction liquid containing area 12. The first containing component 31 and the second containing component 32 are separated by a partition 34 (partition). The remaining positions of the first containing component 31 and the second containing component 32 are formed by an ion exchange membrane 33. Both the first electrode 21 and the second electrode 22 are used for connection to a power supply 40.

[0093] The surfaces of both the first electrode 21 and the second electrode 22 are covered with a gel-like electrolyte. The ion-exchange membrane 33 in each of the aforementioned containers is the lithium-ion selectively permeable membrane described in Example 1. The lithium-containing solution 51 to be treated is lithium-containing brine (same as in Example 1). The recovered solution 52 is a sodium chloride solution (same as in Example 1).

[0094] The lithium extraction methods corresponding to the above-mentioned lithium extraction equipment are as follows:

[0095] Process A (e.g.) Figure 3 The reaction solution container is placed entirely into the reaction solution containing area 12 of the reaction tank 10, with the first container 31 facing the first electrode 21 and the second container 32 facing the second electrode 22. The first electrode 21 and the second electrode 22 are connected to the negative and positive terminals of the power supply 40, respectively, and a constant voltage of 1.2V is applied. This causes lithium ions in the lithium-containing brine to pass through the ion membrane 33 of the first container 31 and be adsorbed onto the lithium-poor first electrode 21, while lithium ions desorbed from the lithium-rich second electrode 22 pass through the ion membrane 33 of the second container 32 and enter the recovery solution 52. That is, as process A continues, the first electrode 21 gradually changes from a lithium-poor state to a lithium-rich state, while the second electrode 22 gradually changes from a lithium-rich state to a lithium-poor state.

[0096] Process B (e.g.) Figure 4The reaction liquid container is rotated to interchange the positions of the first container 31 and the second container 32. After the interchange, the first container 31 faces the lithium-poor second electrode 22, and the second container 32 faces the lithium-rich first electrode 21. The first electrode 21 and the second electrode 22 are connected to the positive and negative terminals of the power supply 40, respectively. A constant voltage of 1.2V is applied, causing lithium ions in the lithium-containing brine to pass through the ion membrane 33 of the first container 31 and be adsorbed onto the lithium-poor second electrode 22, and causing lithium ions desorbed from the lithium-rich first electrode 21 to pass through the ion membrane 33 of the second container 32 and enter the recovery liquid 52. That is, as process B continues, the first electrode 21 gradually changes from a lithium-rich state to a lithium-poor state, while the second electrode 22 gradually changes from a lithium-poor state to a lithium-rich state.

[0097] The above processes A and B are performed alternately, with the lithium ion concentration in the lithium-containing brine decreasing sequentially. As the lithium ion concentration decreases, fresh brine is added, continuously enriching the lithium-rich recovery solution 52. The recovery solution 52 is also replaced with fresh brine according to the change in lithium ion concentration to prevent saturation and loss of lithium ion absorption, thus continuously obtaining a lithium-rich recovery solution 52. During the process, the reaction solution container also rotates according to the corresponding processes A and B.

[0098] Example 3

[0099] The difference between this embodiment and Embodiment 1 is that the lithium-containing solution 51 to be treated is lithium-containing seawater.

[0100] Example 4

[0101] The difference between this embodiment and Embodiment 1 is that the lithium-containing solution 51 to be treated is a lithium-containing waste battery leachate.

[0102] Example 5

[0103] The difference between this embodiment and Embodiment 1 is that the lithium-containing solution 51 to be treated is a lithium precipitation mother liquor.

[0104] Example 6

[0105] The difference between this embodiment and Embodiment 1 is that the lithium-containing solution 51 to be treated is a lithium extraction leaching solution from lithium-containing ore.

[0106] Example 7

[0107] The difference between this embodiment and Embodiment 1 is that the voltage applied in both the electroadsorption and electrodesorption processes is 1.0V.

[0108] Example 8

[0109] The difference between this embodiment and Embodiment 1 is that the voltage applied in both the electroadsorption and electrodesorption processes is 1.1V.

[0110] Example 9

[0111] The difference between this embodiment and Embodiment 1 is that the reaction liquid container includes a frame-shaped first container 31 containing the lithium-containing solution 51 to be treated and a frame-shaped second container 32 containing the recovery liquid 52. The first container 31 and the second container 32 are separate and can be extracted and placed in the reaction liquid containing area 12. The first container 31 and the second container 32 are separated by a partition. When it is necessary to change the lithium-containing brine and the recovery liquid 52, the first container 31 containing the lithium-containing brine and the second container 32 containing the recovery liquid 52 are taken out and their positions are exchanged and placed in the reaction liquid containing area 12.

[0112] Example 10

[0113] The difference between this embodiment and Embodiment 1 is that the lithium iron phosphate electrode is replaced with a lithium manganese oxide electrode.

[0114] Comparative Example 1

[0115] Compared to Example 1, Comparative Example 1 uses a conventional method, such as... Figure 5 The lithium extraction apparatus shown performs lithium extraction processing, specifically including: a reaction tank 10 having a first tank region 11 and a second tank region 13, separated by a non-movable ion-exchange membrane 33 (the same lithium-ion selective permeable membrane as in Example 1); a lithium-rich lithium iron phosphate electrode (first electrode 21) is disposed in the first tank region 11, and a lithium-depleted lithium iron phosphate electrode (second electrode 22) is disposed in the second tank region 13; a voltage of 1.2V is applied by a power supply 40 to perform electro-deintercalation and extraction of lithium. The recovery solution or lithium-containing brine used in each tank region is the same as in Example 1.

[0116] Comparative Example 2

[0117] Compared to Example 1, Comparative Example 2 uses a conventional method, such as... Figure 6 and Figure 7 The lithium extraction device shown performs lithium extraction. In this process, lithium extraction and delithiation are separate modules. The lithium extraction module is shown below. Figure 6 As shown, it includes: a reaction tank 10 having a first tank region 11 and a second tank region 13, separated by a non-movable ion-exchange membrane 33 (the same lithium-ion selective permeable membrane as in Example 1); a lithium-poor lithium iron phosphate electrode (first electrode 21) is disposed in the first tank region 11; and an inert electrode (second electrode 22, specifically the same carbon-containing electrode as used in Example 1) is disposed in the second tank region 13; a voltage of 1.2V is applied by a power supply 40 for individual lithium extraction. The recovery solution or lithium-containing brine used in each tank region is the same as in Example 1.

[0118] The delithiation module includes: a lithium iron phosphate electrode (third electrode 23) in a lithium-rich state is disposed in a first tank zone 11, and an inert electrode (fourth electrode 24, specifically the carbon-containing electrode used in Example 1) is disposed in a second tank zone 13. The first tank zone 11 and the second tank zone 13 are separated by a non-movable membrane (the lithium-ion selective permeable membrane of Example 1). A voltage of 1.2V is applied for individual delithiation. The recovery solution or lithium-containing brine used in each tank zone is the same as in Example 1.

[0119] Test case

[0120] The lithium extraction effects of the lithium extraction devices in Examples 1-2 and Comparative Examples 1-2 were compared, and the results are shown in Table 1.

[0121] Table 1 Lithium extraction effect

[0122]

[0123] As can be seen from Table 1, the lithium-ion extraction efficiency of the examples is higher than that of the comparative examples, and the unit energy consumption during the lithium extraction process is significantly reduced, and the carbon emissions per unit energy consumption can also be reduced accordingly.

[0124] In summary, the lithium extraction method provided in this disclosure is simple to operate, has high lithium extraction efficiency, low energy consumption throughout the process, and generates little carbon emissions, making it low-carbon and environmentally friendly.

[0125] Industrial applicability

[0126] The lithium extraction device provided in this disclosure has a simple structure and is easy to operate. On the one hand, it avoids the cumbersome replacement of lithium insertion / extraction electrodes in existing technologies; on the other hand, it avoids the need to use large amounts of deionized water to clean the ion exchange membrane 33 during the lithium extraction process. This improves lithium extraction efficiency while reducing environmental pollution. The corresponding lithium extraction method is simple to operate, has high lithium extraction efficiency, low energy consumption, and low carbon emissions, making it low-carbon and environmentally friendly.

Claims

1. A lithium extraction device, characterized in that, The lithium extraction device includes a reaction tank, a first electrode, a second electrode, and a reaction liquid container; The reaction tank has a first tank area, a reaction liquid containing area, and a second tank area; the first electrode and the second electrode are respectively disposed in the first tank area and the second tank area, and the reaction liquid containing component is movably disposed in the reaction liquid containing area; both the first electrode and the second electrode are used to connect to a power source. The reaction liquid container includes a first container for holding the lithium-containing solution to be treated and a second container for holding the recovery liquid; The reaction liquid containing area is selectively provided with either the first containing element or the second containing element; The first container has an ion membrane, which allows lithium ions in the lithium-containing solution to pass through the ion membrane of the first container and be adsorbed onto the first electrode; the second container also has an ion membrane, which allows lithium ions desorbed from the first electrode by oxidation to pass through the ion membrane of the second container into the recovery liquid. Alternatively, the first and second containers are independently disposed in the reaction solution containing area; the first container has an ion membrane for lithium ions in the lithium-containing solution to be treated to pass through and be adsorbed onto the lithium-poor or low-lithium state first or second electrode under energized conditions; the second container also has an ion membrane for lithium ions applied to the lithium-rich second or first electrode to pass through and enter the recovery solution under energized conditions. When the reaction liquid containing area is selectively provided with the first container or the second container, both the first container and the second container are removable; when the first container and the second container are jointly provided in the reaction liquid containing area, the first container and the second container are removable or rotatable. When the reaction liquid containing area is selectively provided with the first containing element or the second containing element, the first electrode is a lithium iron phosphate electrode or a lithium manganese oxide electrode, and the second electrode is an inert electrode; the inert electrode includes a carbon-containing electrode, a platinum-containing electrode, or a gold-containing electrode; When the first container and the second container are both disposed in the reaction liquid containing area, the first electrode and the second electrode are both lithium iron phosphate electrodes or both are lithium manganese oxide electrodes. The surfaces of the first electrode and / or the second electrode have a gel-like electrolyte. The ion exchange membrane includes sulfonic acid-based ion exchange membranes, carboxylic acid-based ion exchange membranes, or phosphate-based ion exchange membranes.

2. The lithium extraction apparatus according to claim 1, characterized in that, The lithium extraction device also includes a power source for connecting to the first electrode and the second electrode.

3. The lithium extraction apparatus according to claim 1, characterized in that, The lithium-containing solution to be treated includes at least one of brine, seawater, leachate from waste batteries, lithium precipitation mother liquor, and lithium extraction leachate from ore.

4. The lithium extraction apparatus according to claim 1, characterized in that, The recovered liquid includes at least one of sodium chloride solution, potassium chloride solution, ammonium chloride solution, sodium sulfate solution, potassium sulfate solution, sodium nitrate solution, and potassium nitrate solution.

5. A method for lithium extraction, characterized in that, Lithium extraction is performed using the lithium extraction apparatus described in any one of claims 1-4.

6. The lithium extraction method according to claim 5, characterized in that, When the reaction liquid containing area is selectively provided with either the first containing element or the second containing element; The lithium extraction process includes: Electroadsorption process: A first container containing a lithium-containing solution to be treated is placed in the reaction liquid containing area of ​​the reaction tank. The first electrode and the second electrode are connected to the negative and positive terminals of the power supply, respectively, so that lithium ions in the lithium-containing solution to be treated pass through the ion membrane of the first container and are adsorbed onto the first electrode. Electrodesorption process: Remove the first container containing the remaining solution, place the second container containing the recovery solution into the reaction solution containing area, connect the first electrode and the second electrode to the positive and negative terminals of the power supply respectively, so that the lithium ions desorbed by the oxidation reaction of the first electrode enter the recovery solution through the ion membrane of the second container.

7. The lithium extraction method according to claim 6, characterized in that, The voltage applied during the electro-adsorption process is 1.0V-1.2V.

8. The lithium extraction method according to claim 6, characterized in that, The voltage applied during the electrodesorption process is 1.0V-1.2V.

9. The lithium extraction method according to any one of claims 6-8, characterized in that, The lithium extraction process involves multiple alternating electro-adsorption and electro-desorption processes.

10. The lithium extraction method according to claim 5, characterized in that, When the first container and the second container are both disposed in the reaction liquid containing area; The lithium extraction process includes process A: a first container containing a lithium-containing solution to be treated and a second container containing a recovery liquid are placed in the reaction liquid containing area of ​​the reaction tank, with the first container facing the first electrode in the lithium-poor state and the second container facing the second electrode in the lithium-rich state; the first electrode and the second electrode are connected to the negative and positive terminals of the power supply, respectively, so that lithium ions in the lithium-containing solution to be treated pass through the ion membrane of the first container and are adsorbed onto the first electrode in the lithium-poor state, and lithium ions desorbed from the second electrode in the lithium-rich state pass through the ion membrane of the second container and enter the recovery liquid.

11. The lithium extraction method according to claim 10, characterized in that, The lithium extraction process also includes process B: swapping the positions of the first container and the second container so that the first container faces the lithium-poor second electrode and the second container faces the lithium-rich first electrode; connecting the first electrode and the second electrode to the positive and negative terminals of a power supply, respectively, so that lithium ions in the lithium-containing solution to be treated pass through the ion membrane of the first container and are adsorbed onto the lithium-poor second electrode, and so that lithium ions desorbed from the lithium-rich first electrode pass through the ion membrane of the second container into the recovery solution.

12. The lithium extraction method according to claim 11, characterized in that, The voltage applied during the lithium extraction process is 1.0V-1.2V.

13. The lithium extraction method according to claim 12, characterized in that, The lithium extraction process consists of multiple alternating processes A and B.

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