Methods for preparing supported catalysts using waste lithium batteries and attapulgite and their applications in CO2 conversion

Abstract

This invention belongs to the field of solid waste resource utilization technology, specifically relating to a method for preparing a supported catalyst using waste lithium batteries and attapulgite, and its application in CO2 conversion. Cobalt-titanium compounds are recovered from waste lithium batteries through carbothermic reduction of waste biomass, and then a Co3(Ti)O4 / acidified attapulgite (H-ATP) catalyst is synthesized using a microwave-assisted hydrothermal method. Microwave-assisted hydrothermal induction of Ti... 4+ Doping with Co3O4 leads to lattice defects in the Co3O4. When H-ATP is combined with Co3(Ti)O4, a plasmon resonance effect is generated in the visible-near-infrared region of sunlight, achieving full-spectrum absorption. Furthermore, H-ATP possesses a large specific surface area and abundant active centers for capturing carbon dioxide molecules. The residual biochar produced by biomass reduction of waste lithium-ion battery cathode materials forms charge transfer channels on the carrier surface, accelerating electron transfer and enhancing CO2 adsorption and conversion, thus turning waste into treasure.

Description

Technical Field

[0001] This invention belongs to the field of solid waste resource utilization technology, specifically relating to a method for preparing supported catalysts using waste lithium batteries and attapulgite, and their application in CO2 conversion. Background Technology

[0002] Excessive atmospheric CO2 concentrations contribute to the greenhouse effect and global warming. Therefore, utilizing photothermal synergistic catalysis to convert CO2 and water into superior chemicals and fuels is of great significance. Currently, the focus of developing low-cost, high-efficiency photothermal catalytic systems is on designing and preparing new materials capable of effectively capturing and activating CO2, generating electrons and holes with strong redox capabilities at appropriate conduction and valence band positions, and then, based on the corresponding reduction potential, ultimately converting CO2 into various high-value-added carbon-containing products.

[0003] Attapulgite (ATP) is a natural clay mineral rich in magnesium and aluminum. It is abundant, possesses a rich porous structure, and exhibits stable chemical properties, making it an excellent solid adsorbent. Due to its abundant active sites, it is frequently used as a catalyst support. Co3O4 is an excellent candidate catalyst for CO2 conversion, but its inherent activity remains low. Therefore, designing a highly active and robust Co3O4 catalyst is crucial for improving CO2 conversion efficiency. Summary of the Invention

[0004] This invention provides a novel, inexpensive, efficient, and stable plasma-modified titanium-doped cobalt tetroxide / acid-modified attapulgite nanocomposite material for CO2 capture and catalytic conversion. Its preparation method is simple and does not require complex or expensive equipment, which is beneficial for large-scale application.

[0005] To achieve the objectives of this invention, the following technical solution is adopted:

[0006] (1) Perform pretreatment operations such as discharge, aluminum foil peeling and sieving on waste lithium battery cathode material (marked as LTCO), and then put it into an oven to dry for later use.

[0007] Waste lithium batteries can be a type of secondary lithium battery used in electronic devices such as power banks and mobile phone batteries (the main components are lithium cobalt oxide LiCoO2 and lithium titanate Li4Ti5O). 12 After pretreatment such as disassembly and sieving, the drying time is 4-8 hours;

[0008] (2) Freeze-dry the waste biomass, then grind and sieve it for later use.

[0009] Waste biomass can be one of the following: onion, lotus leaf, pomegranate peel, etc.

[0010] The freeze-drying temperature is -60 to -30℃, and the freeze-drying time is 6-12 hours;

[0011] (3) Mix an appropriate amount of dried waste lithium battery cathode material and sieved waste biomass thoroughly and evenly, then put them into a tube furnace, purge with nitrogen first, and then heat and calcine to obtain a solid sample after carbothermic reduction treatment.

[0012] The mass ratio of dried waste lithium battery cathode material to sieved waste biomass is 1:0.2-0.7, the nitrogen purging time is 10-20 min, and the heating rate is 2-15℃·min. -1 The carbothermal reduction treatment temperature is 500-700℃, and the carbothermal reduction time is 20-40 min;

[0013] (4) After carbothermic reduction treatment, the solid sample is hydrothermally stirred for a certain time, then filtered to recover the filter residue, and dried to obtain a mixed sample of Co3O4, a small amount of TiO2 and biochar, which is labeled as TCO.

[0014] The hydrothermal stirring time for solid samples after carbothermal reduction treatment is 5-15 hours, and the hydrothermal temperature is 60-80℃.

[0015] (5) Disperse attapulgite (ATP) in hydrochloric acid solution by ultrasonication, stir in a water bath at about 80°C for a certain period of time, wash the product until it is neutral, filter it, and then dry it in an oven overnight to obtain H-ATP.

[0016] The acid used to modify ATP can be one of hydrochloric acid, nitric acid, or phosphoric acid.

[0017] (6) Weigh an appropriate amount of TCO and ultrasonically disperse it in a mixture of deionized water and N,N-dimethylformamide (DMF). Add an appropriate amount of H-ATP and hydrothermally stir until H-ATP is uniformly dispersed. Then, microwave hydrothermal reaction for a period of time. Centrifuge, wash, and dry the sample. Finally, calcine it in a muffle furnace to obtain the Co3(Ti)O4 / H-ATP nanocomposite material.

[0018] The total organic carbon (TCO) content is 10%-50% of the mass of H-ATP; the volume ratio of deionized water to DMF is 1:10-30; the hydrothermal stirring time is 60-120 min; the hydrothermal stirring temperature is 70-90℃; the microwave hydrothermal reaction temperature is 140-180℃; the microwave hydrothermal reaction time is 60-120 min; the muffle furnace calcination temperature is 300-400℃; and the calcination time is 60-180 min.

[0019] Finally, under simulated sunlight, the yield of CO2 photocatalytic reduction in pure water of the Co3(Ti)O4-x / H-ATP nanocomposite was determined, where x represents the different contents of TCO relative to the support in step (6).

[0020] The beneficial effects of this invention are as follows:

[0021] (1) This invention first uses the waste biomass carbothermal reduction of waste lithium battery technology to recover cobalt and titanium active components, then acid-modifies attapulgite (ATP) to increase its surface pore structure and specific surface area, and finally uses microwave hydrothermal method to prepare a novel plasma Co3(Ti)O4 / H-ATP nanocomposite material.

[0022] (2) In microwave-assisted hydrothermal reactions, Ti 4+ Doping with Co3O4 induces lattice defects on the Co3O4 surface, which in turn generates a plasmon resonance (LSPR) effect in the visible-near infrared region in the Co3(Ti)O4 / H-ATP composite material. This effectively activates CO2 molecules. H-ATP has a large specific surface area and abundant active centers for capturing CO2 molecules, while biochar forms channels to accelerate electron transfer. This provides a novel pathway for the adsorption and conversion of CO2.

[0023] (3) The present invention uses waste biomass to reduce the residual biochar of LTCO to form channels on the surface of the carrier to accelerate electron transfer, and promotes the recycling of waste lithium batteries, alleviates heavy metal pollution, and realizes the transformation of waste into treasure. Attached Figure Description

[0024] Figure 1 The image shows the XRD pattern of Co3(Ti)O4-30% / H-ATP in Example 1.

[0025] Figure 2 This is a TEM image of Co3(Ti)O4-30% / H-ATP in Example 1.

[0026] Figure 3 a shows the UV-Vis spectra of H-ATP and Co3(Ti)O4-x / H-ATP in Examples 1-3 and Co3(Ti)O4 in Comparative Example 2. Figure 3 b is a scaled-down UV-Vis spectrum with wavelengths from 200 to 1400 cm. Detailed Implementation

[0027] The present invention will now be described in detail with reference to specific embodiments.

[0028] Example 1

[0029] (1) The waste lithium battery cathode material LTCO (i.e., a mixed cathode material of lithium cobalt oxide and lithium titanate) (commercially available) was first subjected to discharge, aluminum foil stripping, and sieving pretreatment; fresh onions were freeze-dried at -45℃ for 8 hours, then ground and sieved (180 mesh) for later use. 3.0g of LTCO and 1.5g of onion powder (mass ratio 1:0.5) were then thoroughly mixed and dried in an oven at 100℃ for 2 hours. The raw materials were placed in a tube furnace, purged with nitrogen for 15 minutes, and then heated at a rate of 10℃·min. -1 The raw material was heated to a set temperature (600℃) and held for 30 minutes to obtain a solid sample after carbothermic reduction. Co and Ti compounds in the solid sample were recovered using a wet separation technique. The specific experimental steps were as follows: the carbothermic reduced solid sample was hydrothermally stirred at 80℃ for 6 hours, then filtered, and the filter residue was recovered to obtain a mixture of Co3O4 and TiO2, labeled as TCO.

[0030] (2) Ultrasonic dispersion: Dissolve 1.5 g of ATP in 75 mL of 3 mol·L⁻¹ -1 The product was stirred in a hydrochloric acid solution at 80°C for 10 hours. It was then washed until neutral, filtered, and dried in an oven overnight to obtain H-ATP.

[0031] (3) 0.23 g Co3(Ti)O4 was ultrasonically dispersed in a mixture of 60 mL deionized water and DMF (1:20), and 0.77 g H-ATP was added. The mixture was placed in a 100 mL microwave reactor and heated at 180 °C for 90 min. After further centrifugation, the mixture was washed three times with deionized water, dried in an oven at 80 °C for 12 h, and finally calcined in a muffle furnace at 350 °C for 90 min. This result was recorded as Co3(Ti)O4-30% / H-ATP.

[0032] Under simulated sunlight and near-infrared light irradiation, the yields of CO2 to CO produced by the photocatalytic reduction of Co3(Ti)O4-30% / H-ATP nanocomposite material in pure water were determined to be 14.7 and 4.8 μmol·g, respectively. -1 ·h -1 .

[0033] The Co3(Ti)O4-30% / H-ATP nanocomposite material prepared in this embodiment was analyzed by X-ray fluorescence spectroscopy (XRF), X-ray diffraction (XRD), and ultraviolet-visible spectroscopy (UV-Vis). Its morphology and structure were observed under transmission electron microscopy (TEM).

[0034] Table 1 shows the XRF results of Co3(Ti)O4-30% / H-ATP in Example 1. It can be seen that its main components are SiO2, Al2O3, MgO, and Fe2O3 in attapulgite, and Co3O4 and TiO2 in waste lithium batteries.

[0035] Table 1

[0036]

[0037] Figure 1 The XRD patterns of H-ATP and Co3(Ti)O4-30% / H-ATP in Example 1 are shown. For the XRD diffraction peaks of H-Co3(Ti)O4-30% / H-ATP, the diffraction peaks at 8.3°, 19.7°, and 26.6° can all be attributed to H-ATP, while TiO2 shows no obvious characteristic peaks. This may be because the content is less than 5% or Ti is doped in the Co3O4 lattice. Compared with its standard card PDF#42-1467, the diffraction peaks of Co3O4 are slightly shifted, corresponding to 37.2°, 45.2°, 59.9°, and 65.5°, respectively, further verifying the possibility of Ti doping in Co3O4.

[0038] Figure 2 The TEM image of Co3(Ti)O4-30% / H-ATP in Example 1 shows that the acid-modified attapulgite is a one-dimensional nanorod with a diameter of about 35 nm. Uniform and highly dispersed Co3(Ti)O4 nanoparticles are grown on the surface of H-ATP, and almost all of the Co3(Ti)O4 nanoparticles have a particle size of 1-5 nm.

[0039] Figure 3 The UV-Vis spectra of H-ATP and Co3(Ti)O4-x / H-ATP in Examples 1-3 and Co3(Ti)O4 in Comparative Example 1 are shown. The light absorption edge of white H-ATP is in the ultraviolet range (385 nm). When H-ATP is complexed with Co3(Ti)O4, the absorption capacity of Co3(Ti)O4-x / H-ATP extends to the visible-infrared region. The localized plasmon resonance effect expands the utilization range of sunlight, specifically from 200 to 1400 cm⁻¹. -1 scaling Figure 3 As shown in b.

[0040] Example 2

[0041] (1) The carbonothermic reduction of waste lithium battery cathode material is consistent with step (1) of Example 1.

[0042] (2) The modified ATP is consistent with step (2) of Example 1.

[0043] (3) 0.09 g Co3(Ti)O4 was ultrasonically dispersed in a mixture of 60 mL deionized water and DMF (1:10), and 0.91 g H-ATP was added. The mixture was placed in a 100 mL microwave reactor and heated at 140 °C for 120 min. After further centrifugation, the mixture was washed three times with deionized water, dried in an oven at 80 °C for 12 h, and finally calcined in a muffle furnace at 300 °C for 180 min. This mixture was recorded as Co3(Ti)O4-10% / H-ATP.

[0044] Under simulated sunlight, the yield of CO2 to CO produced by the photocatalytic reduction of Co3(Ti)O4-10% / H-ATP nanocomposite material in pure water was determined to be 9.8 μmol·g. -1 ·h -1 .

[0045] Example 3

[0046] (1) The carbonothermic reduction of waste lithium battery cathode material is consistent with step (1) of Example 1.

[0047] (2) The modified ATP is consistent with step (2) of Example 1.

[0048] (3) 0.33 g Co3(Ti)O4 was ultrasonically dispersed in a mixture of 60 mL deionized water and DMF (1:30), and 0.67 g H-ATP was added. The mixture was placed in a 100 mL microwave reactor and heated at 180 °C for 60 min. After further centrifugation, the mixture was washed three times with deionized water, dried in an oven at 80 °C for 12 h, and finally calcined in a muffle furnace at 400 °C for 60 min. This mixture was recorded as Co3(Ti)O4-50% / H-ATP.

[0049] Under simulated sunlight irradiation, the yield of CO to CO produced by the photocatalytic reduction of CO2 in pure water using the Co3(Ti)O4-50% / H-ATP nanocomposite material was determined to be 10.9 μmol·g. -1 ·h -1 .

[0050] As shown in Examples 1, 2, and 3, for the Co3(Ti)O4-x / H-ATP nanocomposite material, H-ATP mainly serves as the carrier of Co3(Ti)O4. Acid treatment further increases the specific surface area and the number of active sites of ATP, thereby improving its CO2 adsorption capacity. The biochar residue from carbothermic reduction of waste lithium batteries can increase electron transport on the H-ATP surface, accelerating CO2 adsorption and activation. The LSPR effect caused by the in-situ deposition of Co3(Ti)O4 on the attapulgite surface and its combination with H-ATP expands the absorption range into the infrared region, while simultaneously releasing high-energy hot electrons. The additional heat generated also raises the temperature of the catalyst surface, forming a high-temperature localization.

[0051] Example 4

[0052] (1) The waste lithium battery cathode material LTCO was first pretreated by discharge, aluminum foil peeling, and sieving. Then, fresh lotus leaves were freeze-dried (temperature -30℃, time 12h), ground, and sieved for later use. 3.00g of LTCO and 0.6g of onion powder (mass ratio 1:0.2) were thoroughly mixed and dried in an oven at 100℃ for 2h. The raw materials were placed in a tube furnace, purged with nitrogen for 20min, and then heated at a rate of 5℃·min. -1 The raw material was heated to a set temperature (500℃) and held for 40 minutes to obtain a solid sample after carbothermic reduction. Co and Ti compounds in the solid sample were recovered using a wet separation technique. The specific experimental steps were as follows: the carbothermic reduced solid sample was hydrothermally stirred at 80℃ for 6 hours, then filtered, and the filter residue was recovered to obtain a mixture of CoO and TiO2.

[0053] (2) The modified ATP is consistent with step (2) of Example 1.

[0054] (3) Microwave hydrothermal preparation of Co3(Ti)O4 / H-ATP is consistent with step (3) in Example 1.

[0055] Under simulated sunlight irradiation, the yield of CO to CO produced by the photocatalytic reduction of CO2 in pure water of the Co3(Ti)O4-30% / H-ATP nanocomposite material in Example 4 was determined to be 11.9 μmol·g. -1 ·h -1 .

[0056] Example 5

[0057] (1) The waste lithium battery cathode material LTCO was first subjected to pretreatment operations such as discharge, aluminum foil peeling, and sieving. Then, fresh pomegranate peel was freeze-dried (temperature -65℃, time 6h), ground, and sieved for later use. 3.00g of LCO and 2.1g of onion powder (mass ratio 1:0.7) were then thoroughly mixed and dried in an oven at 100℃ for 2h. The raw materials were placed in a tube furnace, purged with nitrogen for 10min, and then heated at a rate of 10℃·min. -1 The raw material was heated to a set temperature (700℃) and held for 20 minutes to obtain a solid sample after carbothermic reduction. Co and Ti compounds in the solid sample were recovered using a wet separation technique. The specific experimental steps were as follows: the carbothermic reduced solid sample was hydrothermally stirred at 80℃ for 6 hours, then filtered, and the filter residue was recovered to obtain a mixture of CoO and TiO2.

[0058] (2) The modified ATP is consistent with step (2) of Example 1.

[0059] (3) Microwave hydrothermal preparation of Co3(Ti)O4 / H-ATP is consistent with step (3) in Example 1.

[0060] Under simulated sunlight irradiation, the yield of CO to CO produced by the photocatalytic reduction of CO2 in pure water by the Co3(Ti)O4-30% / H-ATP nanocomposite material in Example 5 was determined to be 12.3 μmol·g. -1 ·h -1 .

[0061] Examples 1, 4, and 5 show that the ratio of waste lithium battery cathode material to biomass, carbothermic reduction time, and temperature are key influencing factors for the recovery of cobalt and titanium compounds. Therefore, the prepared catalysts for reducing CO2 to CO vary slightly, but all fall within the preferred range. When the time is too short and the temperature is too low (below 500°C), the carbothermic reduction reaction is incomplete, resulting in a low recovery rate of cobalt and titanium compounds. As the temperature increases, onion powder is converted into biochar, and the gas-solid reaction transforms into a solid-solid carbothermic reduction, promoting the recovery of Co compounds. However, when the calcination time is too long and the temperature is too high (above 700°C), the solid-solid carbothermic reduction may destroy the Co in LCO. 2+ Co 3+ It is reduced to elemental Co. Furthermore, high temperatures not only increase energy consumption, but the LiCO3 produced by the carbothermic reduction of LTCO is unstable at high temperatures, leading to secondary Li pollution.

[0062] Example 6

[0063] (1) The carbonothermic reduction of waste lithium battery cathode material is consistent with step (1) of Example 1.

[0064] (2) The modified ATP is consistent with step (2) of Example 1.

[0065] (3) 0.16 g Co3(Ti)O4 was ultrasonically dispersed in a mixture of 60 mL deionized water and DMF (1:10), and 0.8 g H-ATP was added. The mixture was placed in a 100 mL microwave reactor and heated at 140 °C for 120 min. After further centrifugation, the mixture was washed three times with deionized water, dried in an oven at 80 °C for 12 h, and finally calcined in a muffle furnace at 300 °C for 180 min. This mixture was recorded as Co3(Ti)O4-20% / H-ATP.

[0066] Under simulated sunlight, the yield of CO to CO produced by the photocatalytic reduction of CO2 in pure water using the Co3(Ti)O4-10% / H-ATP nanocomposite material was determined to be 9.9 μmol·g. -1 ·h -1 .

[0067] Example 7

[0068] (1) The carbonothermic reduction of waste lithium battery cathode material is consistent with step (1) of Example 1.

[0069] (2) The modified ATP is consistent with step (2) of Example 1.

[0070] (3) 0.33 g Co3(Ti)O4 was ultrasonically dispersed in a mixture of 60 mL deionized water and DMF (1:10), and 0.67 g H-ATP was added. The mixture was placed in a 100 mL microwave reactor and heated at 140 °C for 120 min. After further centrifugation, the mixture was washed three times with deionized water, dried in an oven at 80 °C for 12 h, and finally calcined in a muffle furnace at 300 °C for 180 min. This mixture was recorded as Co3(Ti)O4-50% / H-ATP.

[0071] Under simulated sunlight, the yield of CO to CO produced by the photocatalytic reduction of CO2 in pure water using the Co3(Ti)O4-10% / H-ATP nanocomposite material was determined to be 10.2 μmol·g⁻¹. -1 ·h -1 .

[0072] Comparative Example 1

[0073] The modified ATP was the same as in step (2) of Example 1. The difference in the subsequent loading process was that in step (3), the cobalt-titanium compound recovered from waste lithium battery cathode material was replaced with a mixture of analytical grade cobalt chloride and titanium chloride. Specifically, 10.32 g of cobalt chloride hexahydrate and 0.53 g of cobalt chloride were ultrasonically dispersed in a mixture of 60 mL of deionized water and DMF (1:20), and 0.77 g of H-ATP was added to a 100 mL microwave reactor and heated at 180 °C for 90 min. After further centrifugation, the mixture was washed three times with deionized water, dried in an oven at 80 °C for 12 h, and finally calcined in a muffle furnace at 350 °C for 90 min, which was recorded as P-Co3(Ti)O4-30% / H-ATP.

[0074] Under simulated sunlight irradiation, the yield of CO to CO produced by the photocatalytic reduction of CO2 in pure water of the P-Co3(Ti)O4-30% / H-ATP nanocomposite material in Comparative Example 1 was only 2.5 μmol·g. -1 ·h -1 .

[0075] Compared to Example 1, the CO2 reduction performance of the P-Co3(Ti)O4-30% / H-ATP nanocomposite material in the above comparative examples is lower. This may be because the cobalt-titanium compounds recovered from waste lithium batteries via carbothermal reduction using onion powder contain biomass carbon. The residual biochar from the carbothermal reduction of waste lithium batteries can increase electron transport on the H-ATP surface, promoting CO2 adsorption and activation. Furthermore, the cost of recovering total CO from the cathode material of carbothermal reduction of waste lithium batteries is far lower than that of analytical grade cobalt chloride and titanium chloride.

[0076] Comparative Example 2

[0077] Same as Example 1, but in step (3), 1g of TCO obtained from carbothermal reduction of waste batteries was added, but ATP was not added. Under simulated sunlight irradiation, the yield of CO2 to CO produced by photocatalytic reduction in pure water of the Co3(Ti)O4 nanocomposite material in Comparative Example 2 was measured to be 1.8 μmol·g. -1 ·h -1 .

[0078] Compared to Example 1, the CO2 reduction performance of Co3(Ti)O4 in the above comparative examples is significantly lower. This is because the presence of H-ATP in Example 1 allows the Co3(Ti)O4-30% / H-ATP nanocomposite to capture more CO2 during the reaction, thereby activating and converting more CO2. Furthermore, Co3(Ti)O4 exhibits better dispersibility and higher activity on the H-ATP support, while the Co3(Ti)O4 in Comparative Example 2 tends to aggregate and accumulate, hindering the exposure of its surface active sites.

[0079] Comparative Example 3

[0080] Same as Example 1, but without the addition of DMF in step (3). Under simulated sunlight irradiation, the yield of CO2 to CO produced by the photocatalytic reduction of the Co3(Ti)O4--30% / H-ATP nanocomposite material in pure water in Comparative Example 3 was measured to be 2.3 μmol·g. -1 ·h -1 .

[0081] Compared to Example 1, the CO2 reduction performance of the Co3(Ti)O4 / H-ATP nanocomposite material in the above comparative examples is much lower. This may be because DMF was not added in the comparative examples, preventing Ti from being doped into the Co3O4 lattice. This could be related to the properties of the solvent under microwave conditions. Under microwave hydrothermal conditions, microwaves cause DMF molecules to vibrate, generating an alternating electromagnetic field. Utilizing the thermal effect of electromagnetic radiation, the temperature of the reaction system rises rapidly in a short time, effectively dissolving TCO and promoting Ti doping into the Co3O4 lattice, thus creating defects. Co3(Ti)O4 grows and nucleates in situ on the H-ATP surface, eventually forming the Co3(Ti)O4 / H-ATP composite material with H-ATP.

Claims

1. A supported catalyst prepared using waste lithium batteries and attapulgite, characterized in that, The catalyst is a Co3(Ti)O4 / acidified attapulgite composite material; The preparation method of the composite material is as follows: (1) Discharge, aluminum foil peeling and screening are performed on the waste lithium battery cathode material before it is dried in an oven for later use. (2) Freeze-dry the waste biomass, then grind and sieve it for later use; the waste biomass is one of onion, lotus leaf, or pomegranate peel. (3) The waste lithium battery cathode material dried in step (1) and the biomass sieved in step (2) are thoroughly mixed and then placed in a tube furnace. Nitrogen gas is first purged and then heated and calcined to obtain a solid sample after carbothermic reduction treatment. (4) The solid sample after carbothermic reduction treatment was hydrothermally stirred, then filtered to recover the filter residue, and dried to obtain a mixed sample of Co3O4, TiO2 and biochar, which was labeled as TCO; (5) Disperse the attapulgite in an acidic solution for modification by ultrasonication. After stirring in a water bath at 80°C, wash the product until it is neutral, filter it, and then dry it in an oven overnight to obtain H-ATP. (6) Weigh TCO and ultrasonically disperse it in a mixture of deionized water and N,N-dimethylformamide. Add H-ATP and perform a microwave hydrothermal reaction. Centrifuge, wash, and dry the sample, and then calcine it in a muffle furnace to obtain the Co3(Ti)O4 / H-ATP supported catalyst.

2. The supported catalyst prepared using waste lithium batteries and attapulgite as described in claim 1, characterized in that, The waste lithium battery cathode material mentioned in step (1) is the cathode material of lithium secondary batteries used in power banks and mobile phone batteries, and its composition is: LiCoO2 and Li4Ti5O. 12 .

3. The supported catalyst prepared using waste lithium batteries and attapulgite as described in claim 1, characterized in that, In step (2), the freeze-drying temperature is -60 to -30 ℃ and the freeze-drying time is 6-12 h.

4. The supported catalyst prepared using waste lithium batteries and attapulgite as described in claim 1, characterized in that, In step (3), the mass ratio of the dried waste lithium battery cathode material to the sieved biomass is 1:0.2-0.7, the nitrogen purging time is 10-20 min, and the heating rate is 2-15 ℃·min. -1 The carbothermal reduction treatment temperature is 500-700 ℃.

5. The supported catalyst prepared using waste lithium batteries and attapulgite as described in claim 1, characterized in that, In step (4), the hydrothermal stirring time is 5-15 h and the hydrothermal stirring temperature is 60-80 ℃.

6. The supported catalyst prepared using waste lithium batteries and attapulgite as described in claim 1, characterized in that, The acid used for modification in step (5) is one of hydrochloric acid, nitric acid, or phosphoric acid.

7. The supported catalyst prepared using waste lithium batteries and attapulgite as described in claim 1, characterized in that, In step (6), TCO accounts for 10%-50% of the mass of H-ATP, and the volume ratio of deionized water to DMF is 1:10-30.

8. The supported catalyst prepared using waste lithium batteries and attapulgite as described in claim 1, characterized in that, In step (6), the microwave hydrothermal reaction temperature is 140-180 ℃ and the microwave hydrothermal reaction time is 60-120 min; the muffle furnace calcination temperature is 300-400 ℃ and the calcination time is 60-180 min.

9. An application of the supported catalyst as described in any one of claims 1-8, characterized in that, The catalyst is used for the photocatalytic reduction of CO2 in pure water.

Images