Preparation method and application of high-dispersity recyclable titanium lithium ion sieve

Abstract

The invention discloses a preparation method and application of a high-dispersity recyclable titanium lithium ion sieve, and relates to a preparation method and application of a lithium ion sieve. The invention creatively provides a titanium lithium ion sieve doped with Fe < 3 + > composite MXene, so that the titanium lithium ion sieve still has the advantages of high dispersity, easiness in recovery, high cycling stability and the like in a high-viscosity water environment. And by utilizing the change of Fe < 3 + > on the band gap of the titanium lithium ion sieve and the water dispersibility and high specific surface area of MXene, the material is resistant to agglomeration in an aqueous solution, the adsorption capacity is increased, and the adsorption rate is accelerated. And by utilizing the change of Fe < 3 + > on the internal crystal lattice of the titanium lithium ion sieve and the good mechanical property of MXene, the titanium lithium ion sieve has low Ti solution loss, obtains magnetism and is easy to recycle and separate. The invention develops the titanium lithium ion sieve which is high in dispersity, high in adsorption capacity, high in adsorption rate, easy to recycle and high in cycling stability; and the method has huge application potential in the field of extracting lithium from the lithium ion sieve.

Description

Technical Field

[0001] The invention relates to a preparation method and application of a lithium ion sieve. Background Art

[0002] With the rapid development of electric vehicles, the amount of scrapped lithium batteries continues to increase. Extracting lithium from lithium battery recycling fluid not only helps the recycling of resources, but also alleviates the supply and demand pressure of lithium resources and promotes green and sustainable development. In recent years, there are many research methods for extracting lithium from lithium battery recycling fluid, such as precipitation, calcination leaching, solvent extraction and adsorption. Among the many methods that have been studied, the adsorption method has the advantages of high efficiency, simplicity, and green environmental protection. However, the performance of this method depends on the choice of adsorbent. Therefore, it is urgent to develop an adsorbent for efficient lithium extraction to meet the challenges of future lithium resource supply.

[0003] Titanium-based lithium ion sieves are widely used due to their low toxicity, low cost, high chemical stability and large absorption capacity of Li + The ability of titanium lithium ion sieve is widely regarded as one of the most promising adsorbents. There are two main methods for the preparation of titanium lithium ion sieves, the solution-gel method and the calcination method. However, the sol-gel method is complicated to operate, and the preparation time of the lithium ion sieve is relatively long. It is not as simple as the solid-phase sintering method, and the raw materials used are more expensive than the solid-phase sintering method. The organic solvents therein will cause certain pressure on the environment. In addition, the adsorption capacity is only slightly higher than that of the solid-phase sintering method. The solid-phase sintering method is more economical and feasible, and easier to industrialize. However, due to high-temperature calcination, the particles aggregate, resulting in a small specific surface area, which is not conducive to the adsorption process. This makes the actual adsorption capacity of titanium lithium ion sieve much smaller than the theoretical adsorption capacity, and the agglomeration phenomenon is prone to occur in the aqueous solution, which limits its industrial application. In addition, compared with salt lake brine and seawater, lithium battery recovery liquid usually contains higher concentrations of metal salts, organic solvents and more impurities and precipitates, making its aqueous solution more viscous. Traditional titanium-based lithium ion sieve materials are difficult to efficiently adsorb Li in these complex components. + .

[0004] Therefore, the preparation of a highly dispersible and easily recyclable lithium ion sieve with high adsorption capacity, low Ti dissolution loss, fast adsorption rate and the ability to cope with complex water environments has become a hot topic in industry research. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a preparation method and application of a highly dispersible and recyclable titanium-based lithium ion sieve.

[0006] The present invention creatively proposes a titanium-based lithium ion sieve doped with Fe 3+ The composite MXene has the advantages of high dispersibility, easy recycling, and strong cycle stability in a high-viscosity water environment. 3+The change in the band gap of titanium-based lithium ion sieves and the water dispersibility and high specific surface area of ​​MXene make it anti-agglomeration in aqueous solution, increase the adsorption amount and accelerate the adsorption rate. 3+ The change of the internal lattice of titanium-based lithium ion sieve and the good mechanical properties of MXene make it have low Ti dissolution loss, obtain magnetic properties and easy recycling separation.

[0007] The present invention develops a titanium-based lithium ion sieve with high dispersibility, high adsorption capacity, high adsorption rate, easy recovery, and high cycle stability. The preparation method is specifically completed according to the following steps:

[0008] 1. Preparation of Ti 3 C 2 MXene powder:

[0009] Ti 3 AlC 2 The powder was added to HF, stirred and reacted for a period of time, and then centrifuged to collect the supernatant; the collected supernatant was washed with deionized water until it was neutral, and then placed in a vacuum drying oven to dry to obtain Ti 3 C 2 MXene powder;

[0010] 2. Preparation of LTFO / MXene:

[0011] ①、Ti 3 C 2 MXene powder was added to ethylene glycol, followed by CH 3 COONa, ultrasound for a period of time,

[0012] Add FeCl 3 6H 2 O, continue ultrasonication for a period of time to obtain a mixed solution;

[0013] ②, transferring the mixed solution to a reaction kettle, and performing a hydrothermal reaction at a temperature of 200°C to 210°C for a period of time to obtain a reaction product; washing the reaction product, and then drying it to obtain a dried reaction product;

[0014] ③. Mix the dried reaction product with LiOH·H 2 O is put into an agate mortar and ground for a period of time to obtain a mixed powder; the mixed powder is transferred to a crucible, and then calcined for a period of time under a nitrogen atmosphere at a temperature of 600°C to 650°C to obtain LTFO / MXene;

[0015] 3. Preparation of HTFO / MXene:

[0016] LTFO / MXene is added to HCl solution, mixed evenly using a shaker, acid-washed for a period of time, and then filtered to obtain a solid substance; the obtained solid substance is washed with deionized water until it is neutral, and then placed in a vacuum drying oven to dry to obtain HTFO / Mxene, which is recorded as a highly dispersed recyclable titanium-based lithium ion sieve.

[0017] A highly dispersible recyclable titanium lithium ion sieve for lithium battery recycling liquid Li + .

[0018] Principle of the present invention:

[0019] The present invention creatively proposes a titanium-based lithium ion sieve doped with Fe 3+ Composite MXene has the advantages of high dispersibility, easy recycling, strong cycle stability, etc. in high viscosity water environment. 3+ Ti 4+ The electrons in Fe-OH are transferred to Fe, which will be beneficial to the H + ionization. While Fe doping, the titanium-based lithium ion sieve can also be magnetized, making it have a large adsorption capacity in powder form, but also easy to separate solids and liquids and reuse. MXene is a material with high specific surface area, good mechanical properties and excellent adsorption properties, and is an important research direction in the field of adsorption materials. 3+ Doping titanium-based lithium ion sieves and compounding MXene can synergistically increase the specific surface area of ​​the lithium ion sieve during adsorption, thereby increasing the adsorption rate and adsorption amount. 3+ Doping increases the stability of the lithium ion sieve by improving the internal lattice and reducing the loss of Ti. The good mechanical properties of MXene compound the titanium-based lithium ion sieve, enabling it to be stably adsorbed in the complex aqueous environment of lithium battery recycling fluid.

[0020] The beneficial effects of the present invention are embodied in:

[0021] Compared with the traditional HTO (traditional titanium-based lithium ion sieve), HTFO / MXene (the highly dispersed recyclable titanium-based lithium ion sieve prepared by the present invention) has a high Fe 3+ The doping and MXene composite has high dispersibility; it is suitable for a variety of complex water environments; and it obtains a higher adsorption capacity and adsorption rate; the adsorption capacity reaches 40.2 mg / g, and the adsorption time is 1 h, which is better than traditional HTO; it also reduces the dissolution of Ti, obtains magnetism, improves the cycle stability, and is easy to recycle; it has great application potential in the field of lithium ion screening and lithium extraction. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 is Li + The relationship between the adsorption capacity and time;

[0023] Figure 2 The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 is Li + The relationship between the adsorption capacity and pH value;

[0024] Figure 3 The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 is + Mg 2+ 、Na + , K + The adsorption amount of each ion in the mixed solution;

[0025] Figure 4 The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 is + 、Co 2+ 、Ni 2+ , Mn 2+ The adsorption amount of each ion in the mixed solution;

[0026] Figure 5 The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 and the conventional titanium-based lithium ion sieve in lithium battery recovery liquid are + The adsorption amount;

[0027] Figure 6 In order to repeatedly recycle the highly dispersed and recyclable titanium-based lithium ion sieve prepared in Example 3, + The adsorption capacity of

[0028] Figure 7 The highly dispersible and recyclable titanium-based lithium ion sieve prepared in Examples 1 to 5 is Li + adsorption capacity. DETAILED DESCRIPTION

[0029] Specific implementation method 1: This implementation method is a method for preparing a highly dispersible and recyclable titanium-based lithium ion sieve, which is specifically completed according to the following steps:

[0030] 1. Preparation of Ti 3 C 2 MXene powder:

[0031] Ti 3 AlC 2 The powder was added to HF, stirred and reacted for a period of time, and then centrifuged to collect the supernatant; the collected supernatant was washed with deionized water until it was neutral, and then placed in a vacuum drying oven to dry to obtain Ti 3 C2 MXene powder;

[0032] 2. Preparation of LTFO / MXene:

[0033] ①、Ti 3 C 2 MXene powder was added to ethylene glycol, followed by CH 3 COONa, ultrasound for a period of time,

[0034] Add FeCl 3 6H 2 O, continue ultrasonication for a period of time to obtain a mixed solution;

[0035] ②, transferring the mixed solution to a reaction kettle, and performing a hydrothermal reaction at a temperature of 200°C to 210°C for a period of time to obtain a reaction product; washing the reaction product, and then drying it to obtain a dried reaction product;

[0036] ③. Mix the dried reaction product with LiOH·H 2 O is put into an agate mortar and ground for a period of time to obtain a mixed powder; the mixed powder is transferred to a crucible, and then calcined for a period of time under a nitrogen atmosphere at a temperature of 600°C to 650°C to obtain LTFO / MXene;

[0037] 3. Preparation of HTFO / MXene:

[0038] LTFO / MXene is added to HCl solution, mixed evenly using a shaker, acid-washed for a period of time, and then filtered to obtain a solid substance; the obtained solid substance is washed with deionized water until it is neutral, and then placed in a vacuum drying oven to dry to obtain HTFO / Mxene, which is recorded as a highly dispersed recyclable titanium-based lithium ion sieve.

[0039] Specific implementation method 2: The difference between this implementation method and specific implementation method 1 is that the mass fraction of HF in step 1 is 40%; the Ti in step 1 3 AlC 2 The mass ratio of the powder to the volume of HF is (4 g to 6 g): 100 mL. The other steps are the same as those in the first embodiment.

[0040] Specific embodiment 3: This embodiment differs from specific embodiment 1 or 2 in that: the stirring reaction temperature in step 1 is 25°C to 30°C, the stirring reaction speed is 600r / min to 800r / min, and the stirring reaction time is 24h to 30h; the centrifugal speed in step 1 is 6000r / min to 8000r / min, and the centrifugal stirring time is 8min to 10min. The other steps are the same as those in specific embodiment 1 or 2.

[0041] Specific embodiment 4: This embodiment differs from specific embodiments 1 to 3 in that: in step 1, the collected supernatant is washed with deionized water until the pH value is 6 to 7; the temperature of the vacuum drying oven in step 1 is 60° C. to 70° C. The other steps are the same as those of specific embodiments 1 to 3.

[0042] Specific implementation method 5: This implementation method is different from specific implementation methods 1 to 4 in that: Ti in step 2① 3 C 2 The mass ratio of MXene powder to ethylene glycol is (0.5 g to 0.6 g): 60 mL; the CH 3 The mass ratio of COONa to the volume ratio of ethylene glycol is (1 g to 3 g): 60 mL. The other steps are the same as those in the first to fourth embodiments.

[0043] Specific embodiment 6: This embodiment differs from specific embodiments 1 to 5 in that: the FeCl 3 6H 2 The mass ratio of O to the volume ratio of ethylene glycol is (0.1 g to 0.7 g): 60 mL; the ultrasonic time in step 2① is 1 h to 2 h. The other steps are the same as those in specific embodiments 1 to 5.

[0044] Specific embodiment 7: This embodiment differs from specific embodiments 1 to 6 in that: the hydrothermal reaction time in step 2 ② is 10 h to 12 h; in step 2 ②, anhydrous ethanol is used to wash the reaction product, and then dried at 60° C. to 80° C. The other steps are the same as those in specific embodiments 1 to 6.

[0045] Specific embodiment 8: This embodiment differs from specific embodiments 1 to 7 in that: the LiOH·H 2 O and Ti as described in step 1 3 C 2 The mass ratio of MXene powder is (0.8-0.9): (0.5-0.6); the grinding time in step 2③ is 10min-20min; the calcination time in step 2③ is 5h-7h. The other steps are the same as those in specific embodiments 1 to 7.

[0046] Specific embodiment 9: This embodiment differs from specific embodiments 1 to 8 in that: the volume ratio of the LTFO / MXene mass HCl solution in step 3 is 1g:100mL; the concentration of the HCl solution in step 3 is 1mol / L; the pickling time in step 3 is 5h to 7h; the temperature of the vacuum drying oven in step 3 is 60°C to 70°C. The other steps are the same as those in specific embodiments 1 to 8.

[0047] Specific embodiment 10: This embodiment is a highly dispersible recyclable titanium lithium ion sieve for lithium battery recovery liquid Li + .

[0048] The following examples are used to verify the beneficial effects of the present invention:

[0049] Example 1: A method for preparing a highly dispersible and recyclable titanium-based lithium ion sieve, characterized in that the preparation method is specifically completed according to the following steps:

[0050] 1. Preparation of Ti 3 C 2 MXene powder:

[0051] 5g Ti 3 AlC 2 The powder was added to 100 mL of 40% HF by mass, and then stirred at 25°C for 24 h at a stirring speed of 600 r / min, and then centrifuged to collect the supernatant; the collected supernatant was washed with deionized water to a pH value of 6, and then placed in a vacuum drying oven at 60°C for 6 h to obtain Ti 3 C 2 MXene powder;

[0052] The centrifugal speed in step 1 is 6000 r / min, and the centrifugal stirring time is 8 min;

[0053] 2. Preparation of LTFO / MXene:

[0054] ①, 0.56g Ti 3 C 2 MXene powder was added to 60 mL of ethylene glycol, followed by 1.495 g of CH 3 COONa, ultrasonic for 1 h, then add 0.135 g FeCl 3 6H 2 O, continue ultrasonication for 1 h to obtain a mixed solution;

[0055] ②, transfer the mixed solution to a reactor, perform a hydrothermal reaction at a temperature of 200°C for 10 hours to obtain a reaction product; wash the reaction product with anhydrous ethanol, and then dry it at 60°C to obtain a dried reaction product;

[0056] ③. Mix the dried reaction product with 0.84g LiOH·H 2 O was put into an agate mortar and ground for 10 min to obtain a mixed powder; the mixed powder was transferred to a crucible, and then calcined at 600 °C in a nitrogen atmosphere for 6 h to obtain LTFO / MXene;

[0057] 3. Preparation of HTFO / MXene:

[0058] 1 g of LTFO / MXene was added to 100 mL of 1 mol / L HCl solution, mixed evenly using a shaker, acid-washed for 6 h, and filtered to obtain a solid substance; the obtained solid substance was washed with deionized water until neutral, and then dried in a vacuum drying oven at a temperature of 60°C to obtain a highly dispersed recyclable titanium-based lithium ion sieve (HTFO / MXene).

[0059] Example 2: The difference between this example and Example 1 is that in step 2①, 0.56 g Ti 3 C 2 MXene powder was added to 60 mL of ethylene glycol, followed by 1.87 g of CH 3 COONa, ultrasonic for 1 h, then add 0.27 g FeCl 3 6H 2 O, and continue ultrasonication for 1 h to obtain a mixed solution. The other steps and parameters are the same as those in Example 1.

[0060] Example 3: The difference between this example and Example 1 is that in step 2①, 0.56 g Ti 3 C 2 MXene powder was added to 60 mL of ethylene glycol, followed by 2.25 g of CH 3 COONa, ultrasonic for 1 h, then add 0.406 g FeCl 3 6H 2 O, and continue ultrasonication for 1 h to obtain a mixed solution. The other steps and parameters are the same as those in Example 1.

[0061] Example 4: The difference between this example and Example 1 is that in step 2①, 0.56 g Ti 3 C 2 MXene powder was added to 60 mL of ethylene glycol, followed by 2.612 g of CH 3 COONa, ultrasonic for 1 h, then add 0.54 g FeCl3 6H 2 O, and continue ultrasonication for 1 h to obtain a mixed solution. The other steps and parameters are the same as those in Example 1.

[0062] Example 5: The difference between this example and Example 1 is that in step 2①, 0.56 g Ti 3 C 2 MXene powder was added to 60 mL of ethylene glycol, followed by 2.995 g of CH 3 COONa, ultrasonic for 1 h, then add 0.677 g FeCl 3 6H 2 O, and continue ultrasonication for 1 h to obtain a mixed solution. The other steps and parameters are the same as those in Example 1.

[0063] The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 was used to recover Li in the lithium battery recovery solution. + For recycling, the concentration of lithium chloride in the lithium battery recycling liquid is 200 mg / L (usually tens to hundreds, 200 mg / L is selected for simulation here), the pH value of the lithium battery recycling liquid is 6.2, and the adsorption capacity is shown in Figure 1 As shown;

[0064] Figure 1 The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 is Li + The relationship between the adsorption capacity and time;

[0065] from Figure 1 It can be seen that the adsorption capacity basically reaches saturation at 40.2 mg / g after 60 minutes.

[0066] The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 was used to recover Li in the lithium battery recovery solution. + The concentration of lithium chloride in the lithium battery recovery liquid is 200 mg / L. The pH value of the lithium battery recovery liquid is adjusted to 2, 4, 6, 8, 10, and 12, respectively. The adsorption capacity is shown in Figure 2 As shown;

[0067] Figure 2 The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 is Li + The relationship between the adsorption capacity and pH value;

[0068] from Figure 2 It can be seen that the adsorption amount increases with the increase of pH value. When the pH is 12, the maximum adsorption capacity is 48.3 mg / g. The adsorption capacity is also very high at pH 2. It also has application potential in lithium battery acid leaching solution.

[0069] The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 was used in Li + Mg 2+ 、Na + , K + Recovery of Li from mixed solution + , where Li + Mg 2+ 、Na + , K + The concentrations were all 200 mg / L and the pH values ​​were all 7. The adsorption capacity was shown in Figure 3 As shown;

[0070] Figure 3 The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 is + Mg 2+ 、Na + , K + The adsorption amount of each ion in the mixed solution;

[0071] from Figure 3 It can be seen that the highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 has a high + The adsorption capacity is 38.7 mg / g for Mg 2+ The adsorption capacity is 4.1 mg / g for Na + The adsorption capacity is 2.3 mg / g for K + The adsorption capacity is 3.2 mg / g. It can be seen that the highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 has a good adsorption capacity for Li + It has good selectivity and can also be applied to salt lake brine.

[0072] The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 was used to recover Li in the lithium battery recovery solution. + 、Co 2 + 、Ni 2+ , Mn 2+ Recycling, Li in lithium battery recycling liquid + 、Co 2+ 、Ni 2+ , Mn 2+ The concentration was 200 mg / L and the pH value was 6.2; the adsorption capacity was shown in Figure 4 As shown;

[0073] Figure 4 The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 is + 、Co 2+ 、Ni 2+ , Mn 2+ The adsorption amount of each ion in the mixed solution;

[0074] from Figure 4 It can be seen that the highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 has a high + The adsorption capacity is 39.4 mg / g for Co 2+ The adsorption capacity is 2.1 mg / g for Ni 2+ The adsorption capacity is 4.1 mg / g for Mn 2+ The adsorption capacity is 3.6 mg / g. It can be seen that the highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 has a good adsorption capacity for Li + There is good selectivity.

[0075] The highly dispersed recyclable titanium lithium ion sieve prepared in Example 3 and the titanium lithium ion sieve (HTO) prepared by the conventional method were used to analyze the Li in the lithium battery recovery solution. + Recycling, Li in lithium battery recycling liquid + The concentration is 200 mg / L, the pH value is 6.2; the adsorption capacity is shown in Figure 5 As shown;

[0076] Figure 5 The highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 and the conventional titanium-based lithium ion sieve in lithium battery recovery liquid are + The adsorption amount;

[0077] from Figure 5 It can be seen that the highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 has a high + The adsorption capacity is 40.2 mg / g, and the adsorption capacity of the conventional titanium-based lithium ion sieve is 35.8 mg / g. It can be seen that the highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 has a good adsorption capacity for Li in the lithium battery recovery liquid. + The adsorption capacity is higher.

[0078] Repeated use of the highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 for Li + The adsorption capacity of lithium chloride in the lithium battery recovery liquid is 200 mg / L, the pH value of the lithium battery recovery liquid is 6.2, and the adsorption capacity is shown in Figure 6 As shown;

[0079] Figure 6 In order to repeatedly recycle the highly dispersed and recyclable titanium-based lithium ion sieve prepared in Example 3, + The adsorption capacity of

[0080] from Figure 6 It can be seen that the highly dispersible recyclable titanium-based lithium ion sieve prepared in Example 3 has a high + The adsorption capacity of Ti decreased from 40.2 mg / g to 34.72 mg / g, and the dissolution loss of Ti decreased from 1.29% and gradually tended to equilibrium. The cycle performance was stable.

[0081] Figure 7 The highly dispersible and recyclable titanium-based lithium ion sieve prepared in Examples 1 to 5 is Li + adsorption capacity.

[0082] from Figure 7 It can be seen that as FeCl 3 6H 2 As O increases, the adsorption amount decreases.

Claims

1. A method for preparing a highly dispersible and recyclable titanium-based lithium ion sieve, characterized in that The preparation method is specifically completed according to the following steps:

1. Preparation of Ti3C2 MXene powder: Ti3AlC2 powder is added to HF, and then stirred to react for a period of time, and then centrifuged to collect the supernatant; the collected supernatant is washed with deionized water until it is neutral, and then placed in a vacuum drying oven to dry, to obtain Ti3C2 MXene powder; 2. Preparation of LTFO / MXene: ①, Ti3C2 MXene powder was added to ethylene glycol, and then CH3COONa was added, ultrasonicated for a period of time, and then FeCl3·6H2O was added, and ultrasonicated for a period of time to obtain a mixed solution; ②, transferring the mixed solution to a reaction kettle, and performing a hydrothermal reaction at a temperature of 200°C to 210°C for a period of time to obtain a reaction product; washing the reaction product, and then drying it to obtain a dried reaction product; ③. Grind the dried reaction product and LiOH·H2O in an agate mortar for a period of time to obtain a mixed powder; transfer the mixed powder to a crucible, and calcine it in a nitrogen atmosphere at a temperature of 600°C to 650°C for a period of time to obtain LTFO / MXene; 3. Preparation of HTFO / MXene: LTFO / MXene is added to HCl solution, mixed evenly using a shaker, acid-washed for a period of time, and then filtered to obtain a solid substance; the obtained solid substance is washed with deionized water until it is neutral, and then placed in a vacuum drying oven to dry to obtain HTFO / Mxene, which is recorded as a highly dispersed recyclable titanium-based lithium ion sieve.

2. The method for preparing a highly dispersible and recyclable titanium-based lithium ion sieve according to claim 1, characterized in that The mass fraction of HF described in step one is 40%; the volume ratio of the mass of the Ti3AlC2 powder described in step one to HF is (4g~6g):100mL.

3. The method for preparing a highly dispersible and recyclable titanium-based lithium ion sieve according to claim 1, characterized in that The temperature of the stirring reaction described in step 1 is 25°C to 30°C, the speed of the stirring reaction is 600r / min to 800r / min, and the time of the stirring reaction is 24h to 30h; the speed of the centrifugation described in step 1 is 6000r / min to 8000r / min, and the time of the centrifugal stirring is 8min to 10min.

4. The method for preparing a highly dispersible and recyclable titanium-based lithium ion sieve according to claim 1, characterized in that In step 1, the collected supernatant is washed with deionized water until the pH value is 6-7; the temperature of the vacuum drying oven in step 1 is 60° C.-70° C.

5. The method for preparing a highly dispersible and recyclable titanium-based lithium ion sieve according to claim 1, characterized in that The mass ratio of the Ti3C2 MXene powder described in step 2① to the volume ratio of ethylene glycol is (0.5g-0.6g): 60mL; the mass ratio of the CH3COONa described in step 2① to the volume ratio of ethylene glycol is (1g-3g): 60mL.

6. The method for preparing a highly dispersible and recyclable titanium-based lithium ion sieve according to claim 1, characterized in that The mass ratio of FeCl3·6H2O to ethylene glycol described in step 2① is (0.1g~0.7g):60mL; the ultrasonic time described in step 2① is 1h~2h.

7. The method for preparing a highly dispersible and recyclable titanium-based lithium ion sieve according to claim 1, characterized in that The time of the hydrothermal reaction in step 2② is 10h to 12h; in step 2②, the reaction product is washed with anhydrous ethanol and then dried at 60°C to 80°C.

8. The method for preparing a highly dispersible and recyclable titanium-based lithium ion sieve according to claim 1, characterized in that The mass ratio of LiOH·H2O described in step 2③ to the Ti3C2 MXene powder described in step 1 is (0.8-0.9):(0.5-0.6); the grinding time described in step 2③ is 10min-20min; the calcination time described in step 2③ is 5h-7h.

9. The method for preparing a highly dispersible and recyclable titanium-based lithium ion sieve according to claim 1, characterized in that The volume ratio of the mass of LTFO / MXene HCl solution described in step three is 1g:100mL; the concentration of the HCl solution described in step three is 1mol / L; the pickling time described in step three is 5h~7h; the temperature of the vacuum drying oven described in step three is 60℃~70℃.

10. Application of a highly dispersible recyclable titanium-based lithium ion sieve prepared by the preparation method according to claim 1, characterized in that A highly dispersible recyclable titanium lithium ion sieve for lithium battery recycling liquid Li + .

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