Waste lithium battery pyrolysis tail gas purifying agent as well as preparation method and application thereof

Abstract

The invention discloses a waste lithium battery pyrolysis tail gas purifying agent and a preparation method and application thereof. The waste lithium battery pyrolysis tail gas purifying agent comprises a salt compound, clay minerals and sodium alkyl benzene sulfonate, wherein the salt compound comprises calcium salt or magnesium salt; the purifying agent comprises the following components in percentage by mass: 20-75% of salt compound; 20%-60% of clay mineral; and 5%-20% of sodium alkyl benzene sulfonate. According to the purifying agent, volatile organic compounds such as carbonic esters, hydrocarbons and alcohols in the waste lithium battery pyrolysis tail gas can be effectively removed by adjusting the dosage and proportion of all the components of the purifying agent, acid fluorine-phosphorus gas can be removed, the purpose of short-range treatment of the pyrolysis tail gas is achieved, the purifying effect of the purifying agent for treating the pyrolysis tail gas is good, and the purifying agent is suitable for industrial production. The preparation method is simple, and the compound raw materials for preparing the purifying agent are cheap and easy to obtain.

Description

Technical Field

[0001] The present application relates to the technical field of waste battery treatment and resource utilization, and in particular to a waste lithium battery pyrolysis tail gas purifier and its preparation method and application. Background Art

[0002] The current recycling process for used lithium batteries primarily involves battery pack disassembly, cell discharge, crushing, pyrolysis, and sorting. The batteries undergo pre-treatment to produce black powder (a mixture of positive and negative electrode powders) and valuable materials such as copper and aluminum powders. Pyrolysis primarily removes the binder polymer from the electrode sheets, promoting the release of the electrode powder from the aluminum foil, facilitating the efficient sorting and recovery of the black powder. During the pyrolysis process, the solvent in the carbonate electrolyte evaporates first, and lithium salts and additives in the electrolyte, such as lithium hexafluorophosphate, decompose to form volatile gases containing fluorine and phosphorus. As the pyrolysis process progresses, the remaining organic matter cracks to form various organic compounds, including hydrocarbons and alcohols. The exhaust gas produced during the pyrolysis process is diverse and contains a wide variety of organic compounds with widely varying properties. It also contains volatile gases such as fluorine and phosphorus, making exhaust gas treatment technically challenging. Summary of the Invention

[0003] The inventors found that the purification of waste lithium battery pyrolysis exhaust gas adopts a segmented treatment method. For example, the solvent of the electrolyte is removed by heating-condensation, hydrocarbons are removed by burning the exhaust gas generated by pyrolysis treatment, and acidic fluorine and phosphorus gases are removed by spraying with absorption liquid. The process flow of pyrolysis exhaust gas purification of waste lithium batteries is long and the equipment process is complicated.

[0004] The embodiments of the present application provide a waste lithium battery pyrolysis tail gas purifier and its preparation method and application, which can solve the problem of difficulty in treating the tail gas generated by the pyrolysis treatment of waste lithium batteries.

[0005] In a first aspect, an embodiment of the present application provides a waste lithium battery pyrolysis tail gas purifier, the purifier comprising a salt compound, a clay mineral, and sodium alkylbenzene sulfonate, wherein the salt compound comprises a calcium salt or a magnesium salt; The content of each component of the purifier is calculated by mass: Salt compounds 20%~75%; Clay minerals 20%~60%; Sodium alkylbenzene sulfonate 5%~20%.

[0006] In some embodiments, the purifier comprises the following components by mass: Salt compounds 40%~60%; Clay minerals 20%~40%; Sodium alkylbenzene sulfonate 10%~15%.

[0007] In some embodiments, the calcium salt includes at least one of calcium hydroxide and calcium oxide.

[0008] In some embodiments, the magnesium salt includes at least one of magnesium hydroxide and magnesium oxide.

[0009] In some embodiments, the clay mineral includes at least one of montmorillonite and kaolinite.

[0010] In some embodiments, the particle size of the salt compound is R, and R satisfies: 25 μm≤R≤75 μm.

[0011] In some embodiments, the purifier has a porous structure; The specific surface area of ​​the purifier is β, 20 m 2 / g≤β≤50 m 2 / g; The average pore diameter of the pore structure of the purifier is r, 2nm≤r≤8nm.

[0012] In a second aspect, the present application provides a method for preparing a waste lithium battery pyrolysis tail gas purifier, comprising: Providing a composite raw material, the composite raw material comprising a uniformly mixed salt compound, a clay mineral and sodium alkylbenzene sulfonate, wherein the salt compound comprises a calcium salt or a magnesium salt; The content of each component of the composite raw material is calculated by mass: Salt compounds 20%~75%; Clay minerals 20%~60%; Sodium alkylbenzene sulfonate 5%~20%; The composite raw materials and water are mixed evenly through a mixing process, and then subjected to a molding process and a drying process to obtain a waste lithium battery pyrolysis tail gas purifier.

[0013] In some embodiments, the mixing process includes: uniformly mixing water and the compound raw material in a weight ratio of 0.1 to 0.5:1; The drying temperature of the drying process is T, and T satisfies: 100°C≤T≤200°C.

[0014] In a third aspect, the present application provides an application of a waste lithium battery pyrolysis tail gas purifier in the pyrolysis treatment of waste lithium batteries, wherein the waste lithium battery pyrolysis tail gas purifier is used to adsorb at least one of volatile organic compounds and acidic fluorine and phosphorus gases generated in the pyrolysis treatment; The volatile organic compounds include at least one of carbonate organic compounds, hydrocarbon organic compounds, and alcohol organic compounds; The waste lithium battery includes at least one of a ternary lithium battery and a lithium iron phosphate battery.

[0015] The waste lithium battery pyrolysis tail gas purifier provided by the present application and its preparation method and application are obtained by compounding three substances: salt compounds, clay minerals and sodium alkylbenzene sulfonate. The clay minerals can be fused with water to facilitate the molding of the purifier during the preparation process, fix the position of the salt compounds in the purifier, and after removing water in the process of preparing the purifier, a purifier with a porous structure is formed, so that the purifier can adsorb gas. In addition, the clay minerals themselves have a good adsorption effect on gas and can effectively remove volatile organic gases such as alcohols, carbonates, and hydrocarbons in the tail gas. Clay minerals can also react with acidic fluorine and phosphorus gases. Sodium alkylbenzene sulfonate has good lipophilicity, which is conducive to the removal of low-boiling point organic matter such as carbonates. Sodium alkylbenzene sulfonate has a good dispersion effect. After adding water in the process of preparing the purifier, sodium alkylbenzene sulfonate helps to promote the uniform dispersion and molding of the salt compounds, clay minerals and sodium alkylbenzene sulfonate, so that after drying and removing water, a uniformly distributed purifier is obtained. Regarding salt compounds, calcium salts and magnesium salts that can react with acidic fluorine and phosphorus gases are selected to remove acidic fluorine and phosphorus gases in the exhaust gas, and water-insoluble salt compounds are selected so that the salt compounds can exist in a granular state. The selected salt compounds have a certain adsorption effect and can adsorb the exhaust gas generated during the pyrolysis treatment, so that the exhaust gas can be more fully contacted with the purifier.

[0016] By adjusting the dosage and ratio of the various components of the purifier, the present application can effectively remove volatile organic compounds such as carbonates, hydrocarbons, alcohols, and acidic fluorine and phosphorus gases from the pyrolysis exhaust gas of waste lithium batteries, thereby achieving the purpose of short-range treatment of pyrolysis exhaust gas. In addition, the purifier has a good purification effect on pyrolysis exhaust gas, the preparation method is simple, and the compound raw materials required for the preparation of the purifier are cheap and easily available. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 This is a physical picture of the waste lithium battery pyrolysis tail gas purifier obtained in Example 1; Figure 2 This is the adsorption-desorption isotherm curve of the waste lithium battery pyrolysis tail gas purifier obtained in Example 1. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0020] The inventors have discovered that the prior art uses a staged approach to purify waste lithium battery pyrolysis exhaust gas. For example, this involves removing electrolyte solvents through heating and condensation, removing hydrocarbons through combustion of the exhaust gas generated by the pyrolysis process, and removing acidic fluorine and phosphorus gases through spraying with an absorbent solution. This process involves a long process flow and complex equipment and procedures. The present invention provides a waste lithium battery pyrolysis exhaust gas purifier, its preparation method, and its application, which can address the difficulty in treating exhaust gas generated by the pyrolysis of waste lithium batteries.

[0021] The waste lithium battery pyrolysis exhaust gas purifier provided in the embodiment of the present application is used to treat the exhaust gas generated by the pyrolysis treatment of waste lithium batteries. The exhaust gas generated by the pyrolysis treatment includes volatile organic compounds such as carbonates, hydrocarbons, alcohols, and acidic fluorine and phosphorus gases.

[0022] The purifier includes salt compounds, clay minerals and sodium alkylbenzene sulfonate, and the salt compounds include calcium salts or magnesium salts. The content of each component of the purifier is calculated by mass: Salt compounds 20%~75%; Clay minerals 20%~60%; Sodium alkylbenzene sulfonate 5%~20%.

[0023] The purifier is obtained by selectively compounding three substances: salt compounds, clay minerals, and sodium alkylbenzene sulfonate. The clay minerals can be fused with water to facilitate the formation of the purifier during the preparation process, fix the position of the salt compounds in the purifier, and after removing water during the preparation process of the purifier, a purifier with a porous structure is formed, allowing the purifier to adsorb gases. In addition, the clay minerals themselves have a good adsorption effect on gases and can effectively remove volatile organic gases such as alcohols, carbonates, and hydrocarbons from exhaust gas. Clay minerals can also react with acidic fluorine and phosphorus gases. Sodium alkylbenzene sulfonate has good lipophilicity, which is conducive to the removal of low-boiling point organic matter such as carbonates. Sodium alkylbenzene sulfonate has a good dispersion effect. After adding water during the preparation process of the purifier, the sodium alkylbenzene sulfonate helps promote the uniform dispersion and formation of the salt compounds, clay minerals, and sodium alkylbenzene sulfonate, thereby obtaining a uniformly distributed purifier after drying to remove water.

[0024] Regarding salt compounds, calcium salts and magnesium salts that can react with acidic fluorine and phosphorus gases are selected to remove acidic fluorine and phosphorus gases in the exhaust gas, and water-insoluble salt compounds are selected so that the salt compounds can exist in a granular state. The selected salt compounds have a certain adsorption effect and can adsorb the exhaust gas generated during the pyrolysis treatment, so that the exhaust gas can be more fully contacted with the purifier.

[0025] By adjusting the dosage and ratio of the various components of the purifier, the present application can simultaneously and effectively remove volatile organic compounds such as alcohols, carbonates, hydrocarbons, and acidic fluorine and phosphorus gases from the pyrolysis exhaust gas of waste lithium batteries, thereby achieving the purpose of short-range treatment of the pyrolysis exhaust gas. Moreover, the purifier has a good purification effect on the pyrolysis exhaust gas, the preparation method is simple, and the compound raw materials required for the preparation of the purifier are cheap and easily available.

[0026] Preferably, the purifier is calculated by mass, and the content of each component is: Salt compounds 40%~60%; Clay minerals 20%~40%; Sodium alkylbenzene sulfonate 10%~15%.

[0027] By further optimizing the dosage and ratio of salt compounds, clay minerals and sodium alkylbenzene sulfonate, it is possible to better balance the simultaneous adsorption of volatile organic compounds such as alcohols, carbonates, hydrocarbons, and acidic fluorine and phosphorus gases in the pyrolysis exhaust gas of waste lithium batteries, and achieve a higher removal rate.

[0028] In some embodiments, the calcium salt includes at least one of calcium hydroxide and calcium oxide.

[0029] In some embodiments, the magnesium salt includes at least one of magnesium hydroxide and magnesium oxide.

[0030] In some embodiments, the clay mineral includes at least one of montmorillonite and kaolinite.

[0031] In some embodiments, the purifier is a water-insoluble salt compound, which facilitates the salt compound to maintain its form during the preparation of the purifier, so that the salt compound in the obtained purifier can adsorb the pyrolysis tail gas, and the acidic fluorine and phosphorus gas can enter the interior of the purifier, react with the salt compound and be consumed. Wherein, the salt compound exists in a granular form, and the particle size of the salt compound is R, and R satisfies: 25μm≤R≤75μm. For example, R can be 25μm, 45μm, 55μm, 65μm, 75μm or any range of the above two. By selecting the particle size R of the salt compound particles within the above range, the salt compound can be more evenly distributed in the purifier, preventing the salt compound particles from being too large and unevenly distributed during the preparation process. At the same time, it is convenient for the salt compound to have a suitable specific surface area to better adsorb the tail gas generated by the pyrolysis of waste lithium batteries.

[0032] In some embodiments, the purifier has a porous structure, enabling it to absorb exhaust gas generated by the pyrolysis of used lithium batteries. The exhaust gas generated by the pyrolysis can enter the spaces within the porous structure and come into contact with the salt compound, clay mineral, and sodium alkylbenzene sulfonate, thereby correspondingly absorbing volatile organic compounds such as carbonates, hydrocarbons, and alcohols in the exhaust gas from the pyrolysis of the used lithium batteries, and reacting with the acidic fluorine and phosphorus gases.

[0033] In some embodiments, the specific surface area of ​​the scavenger is β, 20 m 2 / g≤β≤50 m 2 / g, for example, β can be 20m 2 / g, 25 m 2 / g, 30 m 2 / g, 40 m 2 / g, 50 m 2 / g or any of the above two ranges. By selecting the specific surface area β of the purifier in the above range, the purifier has a suitable specific surface area, so that it can more fully absorb the tail gas generated by pyrolysis. When β is higher than 50 m 2 / g, the specific surface area of ​​the purifier is too large, the purifier is too loose, the gas interception effect is poor, resulting in poor adsorption effect on pyrolysis tail gas, in addition, it is easy to cause the purifier structure strength to be poor and easy to break. When β is lower than 20 m 2 / g, the specific surface area of ​​the purifier is too small, the tail gas generated by pyrolysis is difficult to enter the interior of the purifier, and the adsorption effect of the tail gas generated by pyrolysis is poor.

[0034] In some embodiments, the average pore size of the pore structure of the purifier is r, 2nm≤r≤8nm, for example, r can be 2nm, 3nm, 5nm, 7nm, 8nm or any range of the above two. By selecting the average pore size of the pore structure of the purifier in the above range, it is convenient for the tail gas generated by pyrolysis to enter the space of the pore structure, thereby improving the contact efficiency between the pyrolysis tail gas and the purifier, and the purifier can more efficiently adsorb the gas in the pyrolysis tail gas. When r is higher than 8nm, the average pore size is too large, the specific surface area of ​​the purifier is too small, the contact rate with the pyrolysis tail gas is low, and the purification effect on the tail gas is poor. In addition, it is also easy to cause the collapse of the purifier structure. When r is higher than 2nm, the average pore size is too small, the pyrolysis tail gas is difficult to enter the interior of the purifier, and the adsorption effect of the purifier is poor.

[0035] The present application also provides a method for preparing a waste lithium battery pyrolysis tail gas purifier, which is used to prepare the waste lithium battery pyrolysis tail gas purifier as described above. The preparation method of the purifier comprises: Compound raw materials are provided, which include uniformly mixed salt compounds, clay minerals and sodium alkylbenzene sulfonate, and the salt compounds include calcium salts or magnesium salts.

[0036] The content of each component of the compound raw materials is calculated by mass: Salt compounds 20%~75%; Clay minerals 20%~60%; Sodium alkylbenzene sulfonate 5%~20%; The compound raw materials and water are mixed evenly through a mixing process, and then subjected to a molding process and a drying process to obtain a waste lithium battery pyrolysis tail gas purifier.

[0037] In the composite raw materials of the embodiments of the present application, the salt compounds are all in granular form, and the clay mineral and sodium alkylbenzene sulfonate are all in powder form. The salt compounds, clay minerals, and sodium alkylbenzene sulfonate are preliminarily mixed to obtain the composite raw materials. During the mixing process, water is mixed with the composite raw materials, and the water infiltrates the clay mineral, making the clay mineral viscous. After stirring, the salt compounds, clay minerals, and sodium alkylbenzene sulfonate are uniformly mixed to prevent the salt compounds from settling. The sodium alkylbenzene sulfonate has a good dispersing effect, which facilitates contact between the salt compounds and the clay minerals, thereby making the salt compounds, clay minerals, and sodium alkylbenzene sulfonate more uniformly mixed.

[0038] In some embodiments, the mixing process includes uniformly mixing water and the composite raw material at a weight ratio of 0.1 to 0.5:1, for example, 0.1:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1, or any range thereof. Within the above weight ratio range of water to composite raw material, the clay mineral, after being soaked in water, has a suitable viscosity to better adhere to the salt compound, thereby achieving a more uniform mixing of the salt compound, the clay mineral, and the sodium alkylbenzene sulfonate. Furthermore, the viscosity of the mixture of the composite raw material and water is also suitable, facilitating subsequent molding.

[0039] Among them, after the composite raw materials and water are mixed, the mixture of the composite raw materials and water is molded to obtain a mixed wet material. The molding process can be carried out by granulation, extrusion, etc. to obtain a spherical, strip, sheet, or honeycomb-shaped mixed wet material. After the molding process, the mixed wet material is dried to obtain a waste lithium battery pyrolysis exhaust gas purifier. Figure 1 As shown, the strip-shaped purifier obtained after drying treatment in one embodiment of the present application.

[0040] In some embodiments, the drying temperature of the drying process is T, where T satisfies the following: 100°C ≤ T ≤ 200°C. For example, T can be 100°C, 150°C, 100°C, 180°C, 200°C, or any range thereof. By selecting the drying temperature T within the above range, the appropriate temperature can effectively remove moisture from the mixed wet material while preventing the temperature from damaging the salt compounds, clay minerals, and sodium alkylbenzene sulfonate. Furthermore, the drying temperature T can facilitate molding and pore formation. When the drying temperature T of the drying process is greater than 200°C, the temperature is too high and can easily damage the pore structure.

[0041] The waste lithium battery pyrolysis tail gas purifier described in the embodiments of this application can be used in the pyrolysis treatment of waste lithium batteries. The principle of pyrolysis of waste lithium batteries is to utilize the thermal instability of organic matter in the solid waste of waste lithium batteries. Heating in a pyrolysis reactor under an oxygen-deficient environment causes the organic matter to undergo thermochemical decomposition, generating substances such as gas, oil, and carbon black. This technology, through high-temperature treatment, can effectively decompose organic matter in batteries, achieving the mutual dissociation of battery components and facilitating subsequent resource recovery.

[0042] The waste lithium battery pyrolysis tail gas purifier of the embodiment of the present application is used to adsorb at least one of volatile organic compounds and acidic fluorine and phosphorus gases generated during the pyrolysis process. In some embodiments, the volatile organic compounds include at least one of alcohols, carbonates, and hydrocarbon organic compounds. Carbonate organic compounds include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, and dimethyl carbonate. Alcohol organic compounds include C2H6O2, C 10 H22 O, C 11 H 24 O, C 18 H 38 O, hydrocarbon organic compounds including C9H 18 、C 12 H 24 、C 12 H 16 、C 18 H 36 The fluorine-containing acidic gas includes hydrogen fluoride, and the phosphorus-containing gas includes fluorine oxyphosphorus.

[0043] In some embodiments, the waste lithium batteries include at least one of ternary lithium batteries and lithium iron phosphate batteries.

[0044] The technical solutions of the present application are described below with reference to specific embodiments. The raw materials used in the following embodiments are all from common commercially available products, and the devices or equipment used are all purchased from conventional market sales channels.

[0045] Example 1 Step S100: 60 g of calcium oxide, 30 g of montmorillonite and 10 g of sodium alkylbenzene sulfonate are uniformly mixed to obtain a composite raw material, wherein the particle size of the calcium oxide is 50 μm.

[0046] Step S200: uniformly mix water and compound raw materials in a weight ratio of 0.4:1, and form the mixture of the compound raw materials and water by extrusion to obtain a round strip of mixed wet material with a diameter of 5 mm.

[0047] Step S300: drying the mixed wet material at 150° C. for 1 hour to obtain a waste lithium battery pyrolysis tail gas purifier.

[0048] Among them, the BET method is used to detect the specific surface area β of the purifier and the average pore diameter r of the pore structure. Figure 2 As shown in the figure, the adsorption-desorption isotherm curve of the purifier obtained in this embodiment is obtained by using the BET method. According to the adsorption-desorption isotherm curve, it can be seen that in this embodiment, the specific surface area β of the waste lithium battery pyrolysis exhaust purifier is 29.2m 2 / g, and the average pore diameter r of the pore structure is 5.4 nm.

[0049] The waste lithium battery pyrolysis tail gas purifier is used in the tail gas treatment device to treat the tail gas generated by the pyrolysis of the waste ternary lithium battery. The tail gas treatment temperature is 80°C and the flow rate of the tail gas introduced into the tail gas treatment is 100mL / min.

[0050] In each embodiment and comparative example, the contents of carbonate, alcohol, and hydrocarbon organic gas compounds were detected by mass spectrometry.

[0051] In each embodiment and comparative example, the gas was first absorbed by alkaline solution, and then the fluorine content was obtained by ion chromatography analysis, and the phosphorus content was obtained by ICP (Inductively Coupled Plasma) analysis.

[0052] Gas removal rate = [(gas content before exhaust gas treatment - gas content after exhaust gas treatment) / gas content before exhaust gas treatment)] * 100%.

[0053] In this embodiment, the removal rate of carbonate organic compounds is 87.2%, the removal rate of hydrocarbon organic compounds is 81.5%, the removal rate of alcohol organic compounds is 89.9%, and the removal rate of acidic fluorine and phosphorus gases is 95.3%.

[0054] Example 2 The difference from Example 1 is: In step S100, 60 g of calcium hydroxide, 30 g of montmorillonite and 10 g of sodium alkylbenzene sulfonate are mixed uniformly to obtain a composite raw material, wherein the particle size of the calcium hydroxide is 50 μm.

[0055] In this embodiment, the removal rate of carbonate organic compounds is 85.7%, the removal rate of hydrocarbon organic compounds is 80.2%, the removal rate of alcohol organic compounds is 86.2%, and the removal rate of acidic fluorine and phosphorus gases is 94.6%.

[0056] Example 3 The difference from Example 1 is: In step S100, 50 g of calcium oxide, 35 g of montmorillonite and 15 g of sodium alkylbenzene sulfonate are mixed uniformly to obtain a composite raw material.

[0057] In this embodiment, the removal rate of carbonate organic compounds is 92.4%, the removal rate of hydrocarbon organic compounds is 83.7%, the removal rate of alcohol organic compounds is 90.8%, and the removal rate of acidic fluorine and phosphorus gases is 95.1%.

[0058] Example 4 The difference from Example 1 is: In step S100, 60 g of magnesium oxide, 30 g of montmorillonite, and 10 g of sodium alkylbenzene sulfonate are mixed uniformly to obtain a composite raw material, wherein the particle size of the magnesium oxide is 50 μm.

[0059] In this embodiment, the removal rate of carbonate organic compounds is 77.3%, the removal rate of hydrocarbon organic compounds is 72.8%, the removal rate of alcohol organic compounds is 81.5%, and the removal rate of acidic fluorine and phosphorus gases is 87.9%.

[0060] Example 5 The difference from Example 1 is: In step S100, 60 g of magnesium hydroxide, 30 g of montmorillonite, and 10 g of sodium alkylbenzene sulfonate are mixed uniformly to obtain a composite raw material, wherein the particle size of the magnesium hydroxide is 50 μm.

[0061] In this embodiment, the removal rate of carbonate organic compounds is 74.5%, the removal rate of hydrocarbon organic compounds is 70.4%, the removal rate of alcohol organic compounds is 77.4%, and the removal rate of acidic fluorine and phosphorus gases is 85.1%.

[0062] Example 6 The difference from Example 1 is: In step S100, 50 g of magnesium oxide, 35 g of montmorillonite, and 15 g of sodium alkylbenzene sulfonate are uniformly mixed to obtain a composite raw material, wherein the particle size of the magnesium oxide is 50 μm.

[0063] In this embodiment, the removal rate of carbonate organic compounds is 80.1%, the removal rate of hydrocarbon organic compounds is 74.4%, the removal rate of alcohol organic compounds is 82.6%, and the removal rate of acidic fluorine and phosphorus gases is 86.2%.

[0064] Example 7 The difference from Example 1 is: In step S100, 60 g of calcium oxide, 30 g of kaolinite and 10 g of sodium alkylbenzene sulfonate are mixed uniformly to obtain a composite raw material.

[0065] In this embodiment, the removal rate of carbonate organic compounds is 82.7%, the removal rate of hydrocarbon organic compounds is 76.7%, the removal rate of alcohol organic compounds is 83.9%, and the removal rate of acidic fluorine and phosphorus gases is 94.1%.

[0066] Comparative Example 1 The difference from Example 1 is: In step S100, 65g of calcium oxide and 35g of montmorillonite are mixed evenly, wherein the particle size of the calcium oxide is 50 μm. In step S200, water is mixed evenly with the mixture of calcium oxide and montmorillonite in step S100 at a weight ratio of 0.4:1.

[0067] In this comparative example, the removal rate of carbonate organic compounds was 66.6%, the removal rate of hydrocarbon organic compounds was 63.4%, the removal rate of alcohol organic compounds was 69.3%, and the removal rate of acidic fluorine and phosphorus gases was 95.9%.

[0068] Comparative Example 2 The difference from Example 1 is: In step S100, calcium oxide with a particle size of 50 μm is directly provided. In step S200, water and the calcium oxide in step S100 are directly mixed uniformly at a weight ratio of 0.4:1.

[0069] In this comparative example, the removal rate of carbonate organic compounds was 21.3%, the removal rate of hydrocarbon organic compounds was 19.2%, the removal rate of alcohol organic compounds was 29.7%, and the removal rate of acidic fluorine and phosphorus gases was 95.5%.

[0070] Comparative Example 3 The difference from Example 1 is: In step S100, montmorillonite is directly provided, and in step S200, water is directly mixed with the montmorillonite in step S100 at a weight ratio of 0.4:1.

[0071] In this comparative example, the removal rate of carbonate organic compounds was 44.4%, the removal rate of hydrocarbon organic compounds was 40.8%, the removal rate of alcohol organic compounds was 46.6%, and the removal rate of acidic fluorine and phosphorus gases was 88.2%.

[0072] Comparative Example 4 The difference from Example 1 is: In step S100, 90 g of calcium oxide and 10 g of sodium alkylbenzene sulfonate are uniformly mixed, wherein the particle size of the calcium oxide is 50 μm. In step S200, water is uniformly mixed with the mixture of calcium oxide and sodium alkylbenzene sulfonate in step S100 at a weight ratio of 0.4:1.

[0073] In this comparative example, the removal rate of carbonate organic compounds was 50.9%, the removal rate of hydrocarbon organic compounds was 51.9%, the removal rate of alcohol organic compounds was 60.4%, and the removal rate of acidic fluorine and phosphorus gases was 95.0%.

[0074] Comparative Example 5 The difference from Example 1 is: In step S100, 90 g of montmorillonite and 10 g of sodium alkylbenzene sulfonate are mixed uniformly. In step S200, water is mixed uniformly with the mixture of montmorillonite and sodium alkylbenzene sulfonate in step S100 at a weight ratio of 0.4:1.

[0075] In this embodiment, the removal rate of carbonate organic compounds is 68.6%, the removal rate of hydrocarbon organic compounds is 67.2%, the removal rate of alcohol organic compounds is 73.5%, and the removal rate of acidic fluorine and phosphorus gases is 91.8%.

[0076] The relevant parameters and experimental results in Examples 1 to 7 and Comparative Examples 1 to 5 are shown in Table 1.

[0077] Table 1

[0078] According to Examples 1 to 7 and Comparative Examples 1 to 5 in Table 1, it can be seen that only the purifier prepared by compounding salt compounds, clay minerals and sodium alkylbenzene sulfonate as raw materials can effectively remove volatile organic compounds such as esters, hydrocarbons, alcohols, etc. in the pyrolysis exhaust gas of waste lithium batteries, as well as remove acidic fluorine and phosphorus gases.

[0079] It can be seen from Example 1 and Comparative Example 1 that the purifier includes only salt compounds and clay minerals. Although the adsorption effect of the salt compounds and clay minerals has a certain adsorption effect on hydrocarbons and alcohol organic compounds, due to the absence of sodium alkylbenzene sulfonate, the mixing uniformity of the salt compounds and clay minerals is poor, and the adsorption effect on esters is poor, resulting in the overall removal effect of the purifier on esters, hydrocarbons, and alcohol organic compounds. It is still poor.

[0080] It can be seen from Comparative Examples 2 and 4, and Comparative Examples 3 and 5 that the addition of sodium alkylbenzene sulfonate in the presence of only salt compounds or clay minerals can improve the removal of volatile organic compounds and acidic fluorine and phosphorus gases in the pyrolysis exhaust gas to a certain extent, but the removal effect is still poor.

[0081] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, or article comprising a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, or article. Each embodiment in this specification is described in a related manner. The same or similar parts between the embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

[0082] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A waste lithium battery pyrolysis tail gas purifier, characterized in that: The purifier includes salt compounds, clay minerals and sodium alkylbenzene sulfonate, and the salt compounds include calcium salts or magnesium salts; The content of each component of the purifier is calculated by mass: Salt compounds 20%~75%; Clay minerals 20%~60%; Sodium alkylbenzene sulfonate 5%~20%.

2. The waste lithium battery pyrolysis tail gas purifier according to claim 1, characterized in that The content of each component of the purifier is calculated by mass: Salt compounds 40%~60%; Clay minerals 20%~40%; Sodium alkylbenzene sulfonate 10%~15%.

3. The waste lithium battery pyrolysis tail gas purifier according to claim 1, characterized in that The calcium salt includes at least one of calcium hydroxide and calcium oxide.

4. The waste lithium battery pyrolysis tail gas purifier according to claim 1, characterized in that The magnesium salt includes at least one of magnesium hydroxide and magnesium oxide.

5. The waste lithium battery pyrolysis tail gas purifier according to claim 1, characterized in that The clay mineral includes at least one of montmorillonite and kaolinite.

6. The waste lithium battery pyrolysis tail gas purifier according to claim 1, characterized in that The particle size of the salt compound is R, and R satisfies: 25 μm≤R≤75 μm.

7. The waste lithium battery pyrolysis tail gas purifier according to claim 1, characterized in that The purifier has a porous structure; The specific surface area of ​​the purifier is β, 20 m 2 / g≤β≤50 m 2 / g; The average pore diameter of the pore structure of the purifier is r, 2 nm≤r≤8 nm.

8. A method for preparing a waste lithium battery pyrolysis tail gas purifier, characterized in that: include: Providing a composite raw material, the composite raw material comprising a uniformly mixed salt compound, a clay mineral and sodium alkylbenzene sulfonate, wherein the salt compound comprises a calcium salt or a magnesium salt; The content of each component of the composite raw material is calculated by mass: Salt compounds 20%~75%; Clay minerals 20%~60%; Sodium alkylbenzene sulfonate 5%~20%; The composite raw materials and water are mixed evenly through a mixing process, and then subjected to a molding process and a drying process to obtain a waste lithium battery pyrolysis tail gas purifier.

9. The preparation method according to claim 8, characterized in that The mixing process comprises: uniformly mixing water and the composite raw material in a weight ratio of 0.1 to 0.5:1; The drying temperature of the drying process is T, and T satisfies: 100°C≤T≤200°C.

10. Use of the waste lithium battery pyrolysis tail gas purifier according to any one of claims 1 to 9 in the pyrolysis treatment of waste lithium batteries, wherein the waste lithium battery pyrolysis tail gas purifier is used to adsorb at least one of volatile organic compounds and acidic fluorine and phosphorus gases generated during the pyrolysis treatment; The volatile organic compounds include at least one of carbonate organic compounds, hydrocarbon organic compounds, and alcohol organic compounds; The waste lithium battery includes at least one of a ternary lithium battery and a lithium iron phosphate battery.

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