Lithium extraction device and lithium extraction method

Abstract

Disclosed are a lithium extraction device and a lithium extraction method, relating to the technical field of lithium extraction. In the lithium extraction device, by providing a movable ionic membrane, the ionic membrane can be replaced or adjusted according to requirements, without replacing electrodes, so as to perform multiple adsorption and desorption processes. In this process, the ionic membrane does not need to be cleaned, thereby omitting cleaning water, and greatly saving energy consumption and costs. Moreover, in this process, intercalated and deintercalated electrodes do not need to be replaced back and forth, thereby improving the lithium extraction efficiency.

Description

Lithium extraction device and lithium extraction method Technical Field

[0001] The present disclosure relates to the technical field of lithium extraction, and in particular to a lithium extraction device and a lithium extraction method. Background Art

[0002] Global energy reform and transformation are an undeniable trend, with the rapid development of the electric vehicle industry playing a crucial role. This has led to robust global demand for lithium-ion batteries. Lithium possesses numerous excellent physical and chemical properties, boasting a wide range of functions and applications, earning it the reputation of "the energy metal that drives global progress." Initially used primarily in military applications, lithium products have seen a surge in demand with the rapid development of industries such as new energy, metallurgy, aerospace, and glass manufacturing, leading to a growing demand for lithium, and the development of lithium extraction technologies is gaining increasing attention.

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

[0004] In view of this, the present disclosure is proposed.

[0005] Summary of the Invention

[0006] The purpose of the present disclosure includes providing a lithium extraction device and a lithium extraction method to improve or solve at least one of the above-mentioned technical problems.

[0007] The present disclosure can be implemented as follows:

[0008] In a first aspect, the present disclosure provides a lithium extraction device comprising a reaction tank, a first electrode, a second electrode, and a reaction liquid container;

[0009] The reaction tank comprises a first tank area, a reaction liquid receiving 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; a reaction liquid receiving member is movably disposed in the reaction liquid receiving area; and the first electrode and the second electrode are both used to connect to a power source;

[0010] The reaction liquid container includes a first container for containing the lithium-containing solution to be processed and a second container for containing the recovery liquid;

[0011] The reaction liquid containing area is selectively provided with a first container or a second container; the first container has an ion membrane, so that lithium ions and anions in the lithium-containing solution to be treated pass through under power conditions and are adsorbed on the first electrode and the second electrode respectively; the second container also has an ion membrane, so that lithium ions and anions desorbed from the first electrode and the second electrode pass through and enter the recovery liquid;

[0012] Alternatively, the first container and the second container are independently arranged together in the reaction liquid holding area; the first container has an ion membrane to allow lithium ions in the lithium-containing solution to be treated to pass through and be adsorbed on the lithium-poor or lithium-poor first electrode or the second electrode under power conditions; the second container also has an ion membrane to allow lithium ions on the lithium-rich second electrode or the first electrode to pass through and enter the recovery liquid under power conditions.

[0013] In an optional embodiment, when the reaction liquid containing area is selectively provided with a first containing member or a second containing member, both the first containing member and the second containing member are extractable.

[0014] 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 extractable or rotatable.

[0015] In an optional embodiment, when the reaction liquid containing area is selectively provided with a first container or a second container, the first electrode is a lithium iron phosphate electrode or a lithium manganate electrode, and the second electrode is an inert electrode.

[0016] In alternative embodiments, the inert electrode comprises a carbon-containing electrode, a platinum-containing electrode, or a gold-containing electrode.

[0017] In an optional embodiment, when the first container and the second container are jointly disposed in the reaction liquid containing area, the first electrode and the second electrode are both lithium iron phosphate electrodes or both lithium manganese oxide electrodes.

[0018] In an alternative embodiment, the surface of the first electrode and / or the second electrode has a gel electrolyte.

[0019] In an optional embodiment, the ion membrane includes a sulfonic acid-based ion exchange membrane, a carboxylic acid-based ion exchange membrane, or a phosphate-based ion exchange membrane.

[0020] In an optional embodiment, the lithium extraction device further includes a power source connected to the first electrode and the second electrode.

[0021] In an optional embodiment, the lithium-containing solution to be processed includes at least one of brine, seawater, waste battery leachate, lithium precipitation mother liquor and ore lithium extraction leachate.

[0022] In an optional embodiment, the recovery liquid includes at least one of a sodium chloride solution, a potassium chloride solution, an ammonium chloride solution, a sodium sulfate solution, a potassium sulfate solution, a sodium nitrate solution, and a potassium nitrate solution.

[0023] In a second aspect, the present disclosure provides a lithium extraction method, which uses the lithium extraction device of any of the aforementioned embodiments to perform lithium extraction processing.

[0024] In an optional embodiment, when the reaction liquid holding area is selectively provided with a first holding member or a second holding member;

[0025] The lithium extraction process includes:

[0026] Electrosorption process: a first container containing a lithium-containing solution to be treated is placed in the reaction liquid containing area of ​​the reaction tank, a first electrode and a second electrode are connected to the negative electrode and the positive electrode 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 to 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 to the second electrode;

[0027] Electrodesorption process: remove the first container containing the remaining solution, and place the second container containing the recovered liquid in the reaction liquid holding area. Connect the first electrode and the second electrode to the positive and negative poles of the power supply respectively, so that the lithium ions desorbed by the oxidation reaction of the first electrode enter the recovered liquid through the ion membrane of the second container, and the anions desorbed after the reduction reaction of the second electrode enter the recovered liquid through the ion membrane of the second container.

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

[0029] In an optional embodiment, the voltage applied during the electro-desorption process is 1.0V-1.2V.

[0030] In an optional embodiment, the lithium extraction process includes multiple alternating electrosorption and electrodesorption processes.

[0031] In an optional embodiment, when the first container and the second container are jointly disposed in the reaction liquid containing area;

[0032] The lithium extraction process includes process A: placing a first container containing a lithium-containing solution to be treated and a second container containing a recovered liquid in the reaction liquid containing area of ​​the reaction tank, with the first container arranged toward the lithium-poor first electrode and the second container arranged toward the lithium-rich second electrode; connecting the first electrode and the second electrode to the negative electrode and the positive electrode of the power supply respectively, so that the lithium ions in the lithium-containing solution to be treated pass through the ion membrane of the first container and are adsorbed to the lithium-poor first electrode, and the lithium ions desorbed from the lithium-rich second electrode pass through the ion membrane of the second container and enter the recovered liquid.

[0033] In an optional embodiment, the lithium extraction process also includes process B: swapping the positions of the first container and the second container so that the first container is set toward the lithium-poor second electrode and the second container is set toward the lithium-rich first electrode; connecting the first electrode and the second electrode to the positive electrode and the negative electrode of the power supply respectively, so that the lithium ions in the lithium-containing solution to be treated pass through the ion membrane of the first container and are adsorbed to the lithium-poor second electrode, and the lithium ions desorbed from the lithium-rich first electrode pass through the ion membrane of the second container into the recovery liquid.

[0034] In an optional embodiment, the voltage applied during the lithium extraction process is 1.0V-1.2V.

[0035] In an optional embodiment, the lithium extraction process includes multiple alternating processes A and B.

[0036] The present invention provides a movable ion membrane, which can be replaced or adjusted as needed without replacing the electrode, thereby performing multiple adsorption and desorption processes. During this process, there is no need to clean the ion membrane, which saves cleaning water, greatly saves energy consumption and cost, and, during this process, there is no need to replace the deintercalation and intercalation electrodes back and forth, thereby improving the lithium extraction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0038] FIG1 is a schematic structural diagram of a first lithium extraction device provided by the present disclosure in a first state;

[0039] FIG2 is a schematic structural diagram of the first lithium extraction device provided by the present disclosure in a second state;

[0040] FIG3 is a schematic structural diagram of a second lithium extraction device provided by the present disclosure in a first state;

[0041] FIG4 is a schematic structural diagram of a second lithium extraction device provided by the present disclosure in a second state;

[0042] FIG5 is a schematic structural diagram of a lithium extraction device provided in Comparative Example 1 of the present disclosure;

[0043] FIG6 is a schematic structural diagram of a lithium extraction device provided in Comparative Example 2 of the present disclosure in a first state;

[0044] FIG7 is a schematic structural diagram of the lithium extraction device provided in Comparative Example 2 of the present disclosure in the second state.

[0045] Icons: 10-reaction tank; 11-first tank area; 12-reaction liquid holding area; 13-second tank area; 21-first electrode; 22-second electrode; 23-third electrode; 24-fourth electrode; 31-first container; 32-second container; 33-ion membrane; 34-separator; 40-power supply; 51-lithium-containing solution to be treated; 52-recovery liquid. DETAILED DESCRIPTION

[0046] To make the purpose, technical solutions, and advantages of the embodiments of the present disclosure more clear, the technical solutions in the embodiments of the present disclosure are described clearly and completely below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer were followed. Reagents or instruments used where the manufacturer is not specified are conventional products that can be purchased commercially.

[0047] The lithium extraction device and lithium extraction method provided by the present disclosure are described in detail below.

[0048] 1 to 4 , the present disclosure provides a lithium extraction device, which includes a reaction tank 10 , a first electrode 21 , a second electrode 22 , and a reaction liquid container.

[0049] The reaction tank 10 has a first tank area 11, a reaction liquid holding area 12 and a second tank area 13; the first electrode 21 and the second electrode 22 are respectively arranged in the first tank area 11 and the second tank area 13, and the reaction liquid holding part is movably (for example, it may include a rotating or detachable method) arranged in the reaction liquid holding area 12, and the first electrode 21 and the second electrode 22 are both used to connect to the power supply 40.

[0050] The reaction liquid container includes a first container 31 for containing the lithium-containing solution 51 to be processed and a second container 32 for containing the recovery liquid 52 .

[0051] Referring to Figures 1 and 2 , the reaction liquid holding area 12 can selectively be provided with a first container 31 or a second container 32 depending on the different lithium extraction processes or stages. The first container 31 has an ion membrane 33, through which lithium ions and anions in the lithium-containing solution 51 to be processed pass under electrical conditions and are adsorbed by the first electrode 21 and the second electrode 22, respectively. The second container 32 also has an ion membrane 33, through which lithium ions and anions desorbed by the first and second electrodes 21 and 22 pass and enter the recovered liquid 52. In this configuration, the first container 31 can be placed in the reaction liquid holding area 12 during the electrosorption process. When the electrodesorption process is required, the first container 31 can be removed from the reaction liquid holding area 12 and the second container 32 can be placed in the reaction liquid holding area 12.

[0052] Referring to Figures 3 and 4 , the first container 31 and the second container 32 can also be independently disposed within the reaction liquid holding area 12 . The first container 31 includes an ion membrane 33 to allow lithium ions in the lithium-containing solution 51 to be processed to pass through and be adsorbed on the lithium-poor or lithium-poor first electrode 21 or second electrode 22 under electrical conditions. The second container 32 also includes an ion membrane 33 to allow lithium ions on the lithium-rich second electrode 22 or first electrode 21 to pass through and enter the recovery liquid 52 under electrical conditions. In this configuration, the reaction liquid container can be rotated directly within the reaction liquid holding area 12 to swap the positions of the ion membranes 33 of each container. Alternatively, the entire reaction liquid container can be removed, rotated, and the positions of the ion membranes 33 of each container swapped before being placed back into the reaction liquid holding area 12 .

[0053] In the present disclosure, "lithium-rich state" and "lithium-poor state" are relative concepts, that is, the lithium content corresponding to the "lithium-rich state" is higher than that of the "lithium-poor state".

[0054] It should be noted that after a single lithium extraction is completed, some traditional lithium extraction devices need to replace the lithium-containing solution with a recovery liquid 52, and before replacing the recovery liquid 52, the ion membrane 33 or the lithium extraction tank needs to be cleaned with a large amount of deionized water, which makes the lithium extraction process long, the continuous operation efficiency is low, the water consumption is large, and it pollutes the environment; some other lithium extraction devices are devices that integrate lithium insertion and lithium removal. After the lithium insertion and lithium removal are completed, the lithium insertion electrode and the lithium removal electrode need to be replaced, and then the power is reversed to remove the lithium. This process is cumbersome and it is difficult to replace the electrode, resulting in low lithium extraction efficiency.

[0055] The present invention provides a movable ion membrane 33, which can be replaced or adjusted as needed without replacing the electrode, thereby performing multiple adsorption and desorption processes. During this process, there is no need to clean the ion membrane 33, which saves cleaning water, greatly saving energy consumption and costs (more than 70% of the energy consumption of traditional lithium extraction systems comes from cleaning the ion membrane 33). In addition, during this process, there is no need to replace the desorption electrode back and forth, which improves the lithium extraction efficiency.

[0056] In the present disclosure, the first tank area 11, the reaction liquid holding area 12 and the second tank area 13 are arranged in sequence. For example, in the orientation shown in Figures 1 to 4, the first tank area 11, the reaction liquid holding area 12 and the second tank area 13 are arranged in sequence from left to right.

[0057] When the reaction liquid holding area 12 is selectively provided with the first container 31 or the second container 32, both the first container 31 and the second container 32 are removable, and their specific shapes can be, for example, cylindrical, frame-shaped, or box-shaped. In other words, when the type of solution in the reaction liquid holding area 12 needs to be changed, the unneeded first container 31 or second container 32 can be directly removed and the second container 32 or first container 31 can be replaced as needed. For example, when electrosorption is required (as shown in FIG1 ), the first container 31 containing the lithium-containing solution 51 to be treated is placed in the reaction liquid holding area 12 (the first container 31 can also be placed first, and then the lithium-containing solution 51 to be treated is placed in the first container 31); when electrodesorption is required (as shown in FIG2 ), the first container 31 is removed, and the second container 32 containing the recovered liquid 52 is placed in the reaction liquid holding area 12 (the second container 32 can also be placed first, and then the recovered liquid 52 is placed in the second container 32); when electrosorption is required again (as shown in FIG1 ), the second container 32 is removed, and the first container 31 containing a new lithium-containing solution 51 to be treated is placed in the reaction liquid holding area 12 (the first container 31 can also be placed first, and then the new lithium-containing solution 51 to be treated is placed in the first container 31). In this way, the first container 31 and the second container 32 do not need to be flushed during use, thereby avoiding the problem of the existing device requiring the containers to be cleaned when the liquid in the reaction liquid holding area 12 changes. In addition, there is no need to replace the first electrode 21 and the second electrode 22.

[0058] When the first and second containers 31, 32 are disposed together in the reaction liquid holding area 12, they are removable or rotatable, and may be shaped, for example, as a cylinder, frame, or box. If the first and second containers 31, 32 are removable, then when the positions of the lithium-containing solution 51 to be processed and the recovered liquid 52 need to be switched, the unneeded container can be removed from the corresponding position and the required container can be replaced. Alternatively, the first and second containers 31, 32 can be removed as a whole, rotated, and then placed into the reaction liquid holding area 12 to swap the positions of the ion membranes 33 of each container. If the first and second containers 31, 32 are rotatable, the positions of the lithium-containing solution 51 to be processed and the recovered liquid 52 can be swapped by rotating them to swap the positions of the ion membranes 33 of each container. This approach also avoids the need to rinse the first and second containers 31, 32 during use, and also eliminates the need to replace the first and second electrodes 21, 22.

[0059] For reference, when the reaction liquid holding area 12 is selectively provided with a first container 31 or a second container 32, the first electrode 21 used in the lithium extraction device can be, for example, a lithium iron phosphate electrode or a lithium manganese oxide electrode, and the second electrode 22 can be, for example, 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-deficient state at the beginning of the electrosorption process. As the electrosorption process continues, the first electrode 21 gradually transforms from a lithium-deficient state to a lithium-rich state. The first electrode 21 is in a lithium-rich state at the beginning of the electrodesorption process. As the electrodesorption process continues, the first electrode 21 gradually transforms from a lithium-rich state to a lithium-deficient state. The second electrode 22 is used to adsorb anions in the lithium-containing solution 51 to be treated during the electrosorption process and release the anions into the recovered liquid 52 during the electrodesorption process.

[0060] 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 manganate electrodes. For example, at the beginning of the lithium extraction process, the first electrode 21 is in a lithium-deficient state, and the second electrode 22 is in a lithium-rich state. As the lithium extraction process continues, the first electrode 21 gradually changes from the lithium-deficient state to the lithium-rich state by adsorbing lithium ions from the lithium-containing solution 51 to be processed, while the second electrode 22 gradually changes from the lithium-rich state to the lithium-deficient state by desorbing lithium ions into the recovered liquid 52. When the positions of the first container 31 and the second container 32 are swapped, the first electrode 21 gradually changes from the lithium-rich state to the lithium-deficient state by desorbing lithium ions into the recovered liquid 52, and correspondingly, the second electrode 22 gradually changes from the lithium-deficient state to the lithium-rich state by adsorbing lithium ions from the lithium-containing solution 51 to be processed.

[0061] In some embodiments, the surface of the first electrode 21 and / or the second electrode 22 may have a gel electrolyte. By providing a gel electrolyte on the surface of the electrode, the electrolyte can enter the pores of the electrode plate, which is beneficial to increase the effective contact area and improve the lithium ion insertion and extraction rate.

[0062] In some embodiments, when the reaction liquid containing area 12 is selectively provided with the first containing member 31 or the second containing member 32 , both the first containing member 31 and the second containing member 32 may be formed by an ion membrane 33 .

[0063] In some embodiments, when the first container 31 and the second container 32 are disposed together in the reaction liquid holding area 12, the first container 31 and the second container 32 may be separate or integral. If separate, both the first container 31 and the second container 32 may be formed by an ion membrane 33. If integral, the first container 31 and the second container 32 are separated by a separator 34, and the remaining portion may be formed by the ion membrane 33. Below, taking the example of the first container 31 and the second container 32 both being rectangular parallelepiped, the first container 31 and the second container 32 each independently have an ion membrane 33 that cooperates with the first electrode 21 or the second electrode 22, respectively, during different processing stages. The aforementioned positional reversal of the first and second containers 31 and 32 essentially swaps the positions of the ion membrane 33 cooperating with the first electrode 21 and the ion membrane 33 cooperating with the second electrode 22.

[0064] In the present disclosure, the ion membrane 33 of each container may include a sulfonic acid type ion exchange membrane, a carboxylic acid type ion exchange membrane, or a phosphate type ion exchange membrane, and specifically, may include a lithium ion selective permeable membrane.

[0065] Furthermore, the lithium extraction device further includes a power supply 40 connected to the first electrode 21 and the second electrode 22 .

[0066] For reference, the lithium-containing solution 51 to be treated used in the present disclosure may illustratively include at least one of brine, seawater, waste battery leachate, lithium precipitation mother liquor, and ore lithium extraction leachate. The recovered liquid 52 may illustratively 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.

[0067] As mentioned above, the lithium extraction device provided by the present disclosure has a relatively simple structure and is easy to operate. On the one hand, it can avoid the tedious replacement of lithium electrodes in the prior art. On the other hand, it can avoid the use of a large amount of deionized water to clean the ion membrane 33 during the lithium extraction process, thereby improving the lithium extraction efficiency while reducing pollution to the environment.

[0068] Correspondingly, the present disclosure also provides a lithium extraction method, which uses the above-mentioned lithium extraction device to perform lithium extraction processing.

[0069] When the reaction liquid containing area 12 is selectively provided with the first containing member 31 or the second containing member 32 , the lithium extraction process may include an electrical adsorption process and an electrical desorption process.

[0070] The electrosorption process may refer to (as shown in FIG1 ): 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 (the first container 31 may 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 electrode and the positive electrode of the power supply 40, respectively, so that 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 to 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 to the second electrode 22.

[0071] The electro-desorption process can be referred to (as shown in Figure 2): remove the first container 31 containing the remaining solution, and place the second container 32 containing the recovery liquid 52 in the reaction liquid holding area 12 (the second container 32 can also be placed first, and then the recovery liquid 52 is added to the second container 32). Connect the first electrode 21 and the second electrode 22 to the positive electrode of the power supply 40 and the negative electrode of the power supply 40 respectively, so that the lithium ions desorbed by the oxidation reaction of the first electrode 21 enter the recovery liquid 52 through the ion membrane 33 of the second container 32, and the anions desorbed after the reduction reaction of the second electrode 22 enter the recovery liquid 52 through the ion membrane 33 of the second container 32.

[0072] In some embodiments, the voltage applied during the electrosorption process may be 1.0 V to 1.2 V, such as 1.0 V, 1.05 V, 1.1 V, 1.15 V, or 1.2 V. The electrosorption process may continue, for example, until the lithium ion concentration in the lithium-containing solution to be treated does not exceed a preset concentration, which may be adjusted and set according to actual conditions.

[0073] Similarly, the voltage applied during the electro-desorption process may also be 1.0 V to 1.2 V, such as 1.0 V, 1.05 V, 1.1 V, 1.15 V, or 1.2 V. The electro-desorption process may continue, for example, until the lithium ion concentration in the recovered liquid 52 is no less than a preset concentration, and the preset concentration may also be adjusted and set according to actual conditions.

[0074] In actual operation, the lithium extraction process may include multiple alternating cycles of the above-mentioned electrosorption and electrodesorption processes as needed.

[0075] When the first container 31 and the second container 32 are disposed together in the reaction liquid containing area 12 , the lithium extraction process may include process A and process B.

[0076] Wherein, process A can refer to (as shown in FIG3 ): a first container 31 containing a lithium-containing solution 51 to be treated (the first container 31 can also be placed first, and then the lithium-containing solution 51 to be treated is added to the first container 31) and a second container 32 containing a recovery liquid 52 (the second container 32 can also be placed first, and then the recovery liquid 52 is added to the second container 32) are placed in the reaction liquid holding area 12 of the reaction tank 10, and a lithium-poor first electrode 21 and a lithium-rich first electrode 21 are placed in the first tank area 11 and the second tank area 13 respectively. The first container 31 is positioned toward the first electrode 21, and the second container 32 is positioned toward the second electrode 22. The first electrode 21 and the second electrode 22 are connected to the negative electrode and the positive electrode of the power source 40, respectively. 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-deficient first electrode 21. Lithium ions desorbed from the lithium-rich second electrode 22 pass through the ion membrane 33 of the second container 32 and enter the recovered liquid 52. That is, as process A continues, the first electrode 21 gradually transforms from a lithium-deficient state to a lithium-rich state, while the second electrode 22 gradually transforms from a lithium-rich state to a lithium-deficient state.

[0077] Process B can be referred to (as shown in FIG4 ): the positions of the first container 31 and the second container 32 in process A are swapped, so that the first container 31 is positioned toward the lithium-deficient second electrode 22, and the second container 32 is positioned toward the lithium-rich first electrode 21. The first electrode 21 and the second electrode 22 are connected to the positive and negative electrodes of a power source 40, respectively, so that 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-deficient second electrode 22, and lithium ions desorbed from the lithium-rich first electrode 21 pass through the ion membrane 33 of the second container 32 and enter the recovered liquid 52. That is, as process B continues, the first electrode 21 gradually transitions from a lithium-rich state to a lithium-deficient state, while the second electrode 22 gradually transitions from a lithium-deficient state to a lithium-rich state.

[0078] Similarly, the voltage applied in the above lithium extraction process may also be 1.0V-1.2V, such as 1.0V, 1.05V, 1.1V, 1.15V or 1.2V.

[0079] In actual operation, the lithium extraction process may include multiple alternating processes A and B as needed.

[0080] It should be noted that in the present disclosure, the lithium-containing solution after delithiation can be selectively recycled (when the lithium ions in the lithium-containing solution after delithiation are too low, a new lithium-containing solution is replaced), and the recovered liquid 52 after absorbing lithium ions can also be selectively recycled (when the recovered liquid 52 after absorbing lithium ions reaches saturation, a new recovered liquid 52 is replaced to absorb lithium ions).

[0081] As mentioned above, the lithium extraction method provided by the present disclosure is easy to operate, has high lithium extraction efficiency, and the entire process has low energy consumption and produces low carbon emissions, which is in line with the low-carbon and environmental protection concept.

[0082] The features and performance of the present disclosure are further described in detail below with reference to the embodiments.

[0083] Example 1

[0084] 1 and 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 .

[0085] The reaction tank 10 comprises, from left to right, a first tank section 11, a reaction liquid storage section 12, and a second tank section 13. A first electrode 21 and a second electrode 22 are disposed in the first tank section 11 and the second tank section 13, respectively. The reaction liquid storage includes a box-shaped first container 31 containing the lithium-containing solution 51 to be processed and a box-shaped second container 32 containing the recovered liquid 52. Both the first container 31 and the second container 32 are selectively disposed in the reaction liquid storage section 12 by extraction. The first container 31 is formed by an ion membrane 33. Under an electrical condition, lithium ions and anions in the lithium-containing solution 51 to be processed can pass through the membrane 33 and be adsorbed by the first electrode 21 and the second electrode 22, respectively. The second container 32 is formed by an ion membrane 33. Under an electrical condition, lithium ions and anions desorbed from the first and second electrodes 21 and 22 can pass through the membrane 33 and enter the recovered liquid 52. Both the first and second electrodes 21 and 22 are connected to a power source 40.

[0086] The surfaces of the first electrode 21 and the second electrode 22 are both coated with a gel electrolyte. The ion membrane 33 of each container is a lithium ion selective permeable membrane (purchased from Shanghai Ludun Optoelectronics Technology Co., Ltd.). The lithium-containing solution 51 to be processed is lithium-containing brine (lithium ion concentration of 0.45 g / L). The recovered solution 52 is a sodium chloride solution (concentration of 0.8 mol / L).

[0087] The lithium extraction method corresponding to the above lithium extraction device is as follows:

[0088] Electrosorption process (as shown in Figure 1): The first electrode 21 and the second electrode 22 are connected to the negative and positive electrodes of a power source 40, respectively. A constant voltage of 1.2V is applied, causing lithium ions in the lithium-containing brine to be adsorbed onto the lithium-deficient lithium iron phosphate electrode through the ion membrane 33 of the first container 31. Furthermore, anions in the lithium-containing brine are adsorbed onto the carbon-containing electrode slurry through the ion membrane 33 of the first container 31. The lithium-containing brine is converted into delithiated brine through the electrosorption process. The delithiated brine is then stored for reuse or discarded, leaving the first container 31 for reuse in the next electrosorption process.

[0089] During the electro-desorption process (as shown in Figure 2), the first container 31 is removed, and a second container 32 filled with sodium chloride solution is placed within the reaction liquid holding area 12. The first electrode 21 and the second electrode 22 are connected to the positive and negative electrodes of the power supply 40, respectively. A constant voltage of 1.2V is applied. Lithium ions desorbed by the oxidation reaction of the first electrode 21 pass through the ion membrane 33 of the second container 32 into the recovery liquid 52, and anions desorbed by the reduction reaction of the second electrode 22 pass through the ion membrane 33 of the second container 32 into the recovery liquid 52. The recovery liquid 52 collects the lithium ions and anions desorbed by the first and second containers 31 and 32 to form a lithium-rich recovery liquid 52. The lithium-rich recovery liquid 52 is reused or stored, and the second container 32 is reused for the next electro-desorption process.

[0090] The above-mentioned electrosorption process and electrodesorption process are alternately performed in sequence. During the process, the lithium ion concentration of the lithium-containing brine is gradually reduced. As the lithium ion concentration decreases, the lithium-containing brine is replaced with fresh brine. The lithium ions in the lithium-rich recovery liquid 52 are continuously enriched. The recovery liquid 52 is replaced with fresh recovery liquid 52 according to the change in lithium ion concentration to prevent it from being saturated and unable to absorb lithium ions, thereby continuously obtaining lithium-rich recovery liquid 52. During the process, the first container 31 and the second container 32 in the reaction containment area are also replaced according to the corresponding electrosorption process and electrodesorption process.

[0091] Example 2

[0092] 3 and 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 solution container, and a power supply 40 .

[0093] The reaction tank 10 comprises, from left to right, a first tank section 11, a reaction liquid storage section 12, and a second tank section 13. A first electrode 21 and a second electrode 22 are disposed in the first tank section 11 and the second tank section 13, respectively. The reaction liquid storage section comprises a cylindrical first container 31 containing a lithium-containing solution 51 to be processed and a cylindrical second container 32 containing a recovered liquid 52. The first and second containers 31, 32 are integral and rotatable within the reaction liquid storage section 12. The first and second containers 31, 32 are separated by a partition 34 (separator). The remaining portions of the first and second containers 31, 32 are formed by an ion membrane 33. Both the first and second electrodes 21, 22 are connected to a power source 40.

[0094] The surfaces of the first electrode 21 and the second electrode 22 are both coated with a gel electrolyte. The ion membrane 33 of each container is the lithium ion selective 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).

[0095] The lithium extraction method corresponding to the above lithium extraction device is as follows:

[0096] Process A (as shown in FIG3 ): The entire reaction liquid container is placed within the reaction liquid holding 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 electrodes of a power source 40 , respectively. A constant voltage of 1.2 V 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-deficient first electrode 21 . Furthermore, 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 liquid 52 . That is, as process A continues, the first electrode 21 gradually transforms from a lithium-deficient state to a lithium-rich state, while the second electrode 22 gradually transforms from a lithium-rich state to a lithium-deficient state.

[0097] Process B (as shown in FIG4 ): Rotate the reaction liquid container to swap the positions of the first container 31 and the second container 32. After the swap, the first container 31 faces the lithium-deficient second electrode 22, and the second container 32 faces the lithium-rich first electrode 21. Connect the first electrode 21 and the second electrode 22 to the positive and negative electrodes of a power source 40, respectively, and apply a constant voltage of 1.2V. 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-deficient second electrode 22. Furthermore, lithium ions desorbed from the lithium-rich first electrode 21 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-deficient state, while the second electrode 22 gradually changes from a lithium-deficient state to a lithium-rich state.

[0098] By alternating between the above-mentioned processes A and B, the lithium ion concentration of the lithium-containing brine is gradually reduced. As the lithium ion concentration decreases, the lithium-containing brine is replaced with fresh brine, and the lithium ions in the lithium-rich recovered liquid 52 are continuously enriched. The recovered liquid 52 is replaced with fresh recovered liquid 52 according to the change in lithium ion concentration to prevent it from being saturated and unable to absorb lithium ions, thereby continuously obtaining lithium-rich recovered liquid 52. During the process, the reaction liquid container also rotates according to the corresponding processes A and B.

[0099] Example 3

[0100] The difference between this embodiment and embodiment 1 is that the lithium-containing solution 51 to be treated is lithium-containing seawater.

[0101] Example 4

[0102] 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.

[0103] Example 5

[0104] The difference between this embodiment and embodiment 1 is that the lithium-containing solution 51 to be treated is a lithium-containing lithium precipitation mother liquor.

[0105] Example 6

[0106] The difference between this embodiment and embodiment 1 is that the lithium-containing solution 51 to be treated is a lithium leaching solution extracted from a lithium-containing ore.

[0107] Example 7

[0108] The difference between this embodiment and embodiment 1 is that the voltage applied during the electrosorption and electrodesorption processes is 1.0 V.

[0109] Example 8

[0110] The difference between this embodiment and embodiment 1 is that the voltage applied during the electrosorption and electrodesorption processes is 1.1V.

[0111] Example 9

[0112] 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 split and are arranged in the reaction liquid holding area 12 in an extractable manner. The first container 31 and the second container 32 are separated by a partition. When the lithium-containing brine and the recovery liquid 52 need to be replaced, 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 holding area 12.

[0113] Example 10

[0114] The difference between this embodiment and embodiment 1 is that the lithium iron phosphate electrode is replaced by a lithium manganate electrode.

[0115] Comparative Example 1

[0116] Compared to Example 1, Comparative Example 1 uses a conventional lithium extraction apparatus as shown in FIG5 for lithium extraction. Specifically, the apparatus includes: a reaction tank 10 having a first tank section 11 and a second tank section 13, separated by a non-removable ion 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 section 11, and a lithium-poor lithium iron phosphate electrode (second electrode 22) is disposed in the second tank section 13. A voltage of 1.2 V is applied by a power supply 40 to perform electrical deintercalation and lithium extraction. The recovered liquid or lithium-containing brine used in each tank section is the same as in Example 1.

[0117] Comparative Example 2

[0118] Compared with Example 1, Comparative Example 2 uses a conventional lithium extraction device as shown in Figures 6 and 7 for lithium extraction. In this process, lithium extraction and lithium removal are separate modules. The lithium extraction module is shown in Figure 6 and includes: a reaction tank 10 having a first tank area 11 and a second tank area 13, which are separated by a non-removable ion membrane 33 (the same lithium ion selective permeable membrane as in Example 1). A lithium-deficient lithium iron phosphate electrode (first electrode 21) is provided in the first tank area 11, and an inert electrode (first electrode 22, specifically the same carbon-containing electrode used in Example 1) is provided in the second tank area 13. A voltage of 1.2V is applied by a power supply 40 to perform separate lithium extraction. The recovered liquid or lithium-containing brine used in each tank area is the same as in Example 1.

[0119] The lithium removal module includes a lithium-rich lithium iron phosphate electrode (third electrode 23) disposed within the first tank section 11 and an inert electrode (fourth electrode 24, specifically the carbon-containing electrode used in Example 1) disposed within the second tank section 13. The first and second tank sections 11 and 13 are separated by a non-removable diaphragm (the same lithium ion selective permeable membrane used in Example 1). Delithiation is performed independently by applying a voltage of 1.2 V. The recovered liquid or lithium-containing brine used in each tank section is the same as in Example 1.

[0120] Test example

[0121] The lithium extraction effects of the lithium extraction devices of Examples 1-2 and Comparative Examples 1-2 were compared, and the results are shown in Table 1.

[0122] Table 1 Lithium extraction effect

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

[0124] In summary, the lithium extraction method provided by the present disclosure is simple to operate, has high lithium extraction efficiency, and the entire process has low energy consumption, produces low carbon emissions, and is low-carbon and environmentally friendly. Industrial Applicability

[0125] The lithium extraction device provided by the present disclosure has a relatively simple structure and is easy to operate. This device avoids the tedious back-and-forth replacement of lithium-insertion and de-insertion electrodes required in the prior art, while also avoiding the need to clean the ion membrane 33 with large amounts of deionized water during the lithium extraction process. This improves lithium extraction efficiency while also reducing environmental pollution. The corresponding lithium extraction method is simple to operate, highly efficient, and has low energy consumption and low carbon emissions throughout the process, resulting in a low-carbon and environmentally friendly approach.

Claims

1. A lithium extraction device, characterized in that: The lithium extraction device comprises a reaction tank, a first electrode, a second electrode and a reaction liquid container; The reaction tank comprises a first tank area, a reaction liquid containing area and a second tank area; the first electrode and the second electrode are respectively arranged in the first tank area and the second tank area, the reaction liquid containing member is movably arranged in the reaction liquid containing area, and the first electrode and the second electrode are both used to connect to a power source; The reaction liquid container comprises a first container for containing the lithium-containing solution to be treated and a second container for containing the recovery liquid; The reaction liquid containing area is selectively provided with the first containing member or the second containing member; the first containing member has an ion membrane, so that lithium ions and anions in the lithium-containing solution to be treated pass through under power-on conditions and are adsorbed on the first electrode and the second electrode respectively; the second containing member also has an ion membrane, so that lithium ions and anions desorbed from the first electrode and the second electrode pass through and enter the recovery liquid; Alternatively, the first container and the second container are independently arranged together in the reaction liquid containing area; the first container has an ion membrane to allow lithium ions in the lithium-containing solution to be treated to pass through and be adsorbed on the first electrode or the second electrode in a lithium-poor or lithium-poor state under power conditions; the second container also has an ion membrane to allow lithium ions on the second electrode or the first electrode in a lithium-rich state to pass through and enter the recovery liquid under power conditions.

2. The lithium extraction device according to claim 1, characterized in that: When the reaction liquid containing area is selectively provided with the first containing member or the second containing member, both the first containing member and the second containing member are extractable.

3. The lithium extraction device according to claim 1, characterized in that: When the first container and the second container are disposed together in the reaction liquid containing area, the first container and the second container are extractable or rotatable.

4. The lithium extraction device according to claim 1 or 2, characterized in that: When the reaction liquid containing area is selectively provided with the first containing member or the second containing member, the first electrode is a lithium iron phosphate electrode or a lithium manganate electrode, and the second electrode is an inert electrode.

5. The lithium extraction device according to claim 4, characterized in that: The inert electrode includes a carbon-containing electrode, a platinum-containing electrode or a gold-containing electrode.

6. The lithium extraction device according to claim 1 or 3, characterized in that: When the first container and the second container are disposed together 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.

7. The lithium extraction device according to any one of claims 1 to 6, characterized in that: The first electrode and / or the second electrode has a gel electrolyte on its surface.

8. The lithium extraction device according to any one of claims 1 to 7, characterized in that: The ion membrane includes a sulfonic acid-based ion exchange membrane, a carboxylic acid-based ion exchange membrane or a phosphate-based ion exchange membrane.

9. The lithium extraction device according to any one of claims 1 to 8, characterized in that: The lithium extraction device also includes a power source connected to the first electrode and the second electrode.

10. The lithium extraction device according to any one of claims 1 to 9, characterized in that: The lithium-containing solution to be treated includes at least one of brine, seawater, waste battery leaching solution, lithium precipitation mother liquor and ore lithium extraction leaching solution.

11. The lithium extraction device according to any one of claims 1 to 10, characterized in that: The recovery liquid includes at least one of a sodium chloride solution, a potassium chloride solution, an ammonium chloride solution, a sodium sulfate solution, a potassium sulfate solution, a sodium nitrate solution and a potassium nitrate solution.

12. A method for extracting lithium, characterized in that: The lithium extraction process is carried out using the lithium extraction device described in any one of claims 1 to 11.

13. The lithium extraction method according to claim 12, characterized in that: When the reaction liquid containing area is selectively provided with the first containing member or the second containing member; The lithium extraction process includes: Electrosorption 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 electrode and the positive electrode of the power supply respectively, so that the lithium ions in the lithium-containing solution to be treated pass through the ion membrane of the first container and are adsorbed to the a first electrode, and allowing anions in the lithium-containing solution to be treated to pass through the ion membrane of the first container and be adsorbed to the second electrode; Electrodesorption process: take out the first container containing the remaining solution, place the second container containing the recovery liquid in the reaction liquid containing area, connect the first electrode and the second electrode to the positive electrode and the negative electrode of the power supply respectively, so that the lithium ions desorbed by the oxidation reaction of the first electrode enter the recovery liquid through the ion membrane of the second container, and the anions desorbed after the reduction reaction of the second electrode enter the recovery liquid through the ion membrane of the second container.

14. The lithium extraction method according to claim 13, characterized in that: The voltage applied during the electrosorption process was 1.0V-1.2V.

15. The lithium extraction method according to claim 13, characterized in that: The voltage applied during the electro-desorption process was 1.0V-1.2V.

16. The lithium extraction method according to any one of claims 13 to 15, characterized in that: The lithium extraction process includes multiple alternating electrosorption and electrodesorption processes.

17. The lithium extraction method according to claim 12, characterized in that: When the first container and the second container are disposed together in the reaction liquid containing area; The lithium extraction process includes process A: placing a first container containing a lithium-containing solution to be treated and a second container containing a recovered liquid in the reaction liquid containing area of ​​the reaction tank, so that the first container is arranged toward the first electrode in a lithium-poor state, and the second container is arranged toward the second electrode in a lithium-rich state; connecting the first electrode and the second electrode to the negative electrode and the positive electrode of the power supply respectively, so that the lithium ions in the lithium-containing solution to be treated pass through the ion membrane of the first container and are adsorbed to the first electrode in a lithium-poor state, and the lithium ions desorbed from the second electrode in a lithium-rich state pass through the ion membrane of the second container into the recovered liquid.

18. The lithium extraction method according to claim 17, 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 is set toward the second electrode in a lithium-poor state, and the second container is set toward the first electrode in a lithium-rich state; connecting the first electrode and the second electrode to the positive electrode and the negative electrode of the power supply respectively, so that the lithium ions in the lithium-containing solution to be treated pass through the ion membrane of the first container and are adsorbed to the second electrode in a lithium-poor state, and the lithium ions desorbed from the first electrode in a lithium-rich state enter the recovery liquid through the ion membrane of the second container.

19. The lithium extraction method according to claim 17 or 18, characterized in that: The voltage applied during the lithium extraction process is 1.0V-1.2V.

20. The lithium extraction method according to claim 19, characterized in that: The lithium extraction process includes multiple alternating processes A and B.

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