Resourceful treatment method of silicon-aluminum-based waste catalyst

Abstract

The invention belongs to the technical field of resource recycling, and discloses a resourceful treatment method of a silicon-aluminum-based waste catalyst, which comprises the following steps: putting a silicon-aluminum-based waste catalyst raw material into a crushing device to reduce the granularity of the silicon-aluminum-based waste catalyst; the crushed silicon-aluminum-based waste catalysts are screened through the screening assembly, then the silicon-aluminum-based waste catalysts with different particle sizes are separated, the silicon-aluminum-based waste catalyst raw materials with proper particle sizes can be screened out through the screening assembly, and the silicon-aluminum-based waste catalyst raw materials with large particle sizes are collected. The silicon-aluminum-based waste catalyst raw material with a large particle size can be conveyed into the crushing device again through the circulating assembly, and then secondary crushing treatment is performed, so that the crushed silicon-aluminum-based waste catalyst raw material is uniform in particle size, and the contact area of the silicon-aluminum-based waste catalyst raw material and a reaction solvent is guaranteed; and the recovery efficiency of the silicon-aluminum material and the valuable metal in the silicon-aluminum-based waste catalyst is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of resource recycling, and particularly relates to a method for resource treatment of silicon-aluminum-based waste catalysts. Background Art

[0002] Due to their good catalytic activity, selectivity and stability, silicon-aluminum-based catalysts are widely used in many fields such as petroleum refining and chemical production. In the process of petroleum catalytic cracking, silicon-aluminum-based catalysts can convert heavy oil into light oil, improving the yield and quality of fuels such as gasoline and diesel. They also play a key role in chemical reactions such as isomerization and alkylation, helping to improve the reaction efficiency and product purity.

[0003] Recycling valuable metals and silicon-aluminum materials from waste catalysts has important economic and environmental significance. On the one hand, waste catalysts contain a certain amount of valuable metals such as aluminum, nickel, molybdenum, etc. The recovery of these metals can reduce the dependence on primary mineral resources and lower the production cost of metals. On the other hand, recycling silicon-aluminum materials can achieve resource recycling, reduce the emission of solid waste, and reduce the environmental pressure.

[0004] At present, there are various methods for treating silicon-aluminum-based waste catalysts. Although the traditional acid leaching method can effectively leach out valuable metals, the consumption of acid is large, and the impurity content in the leaching solution is high. The subsequent separation and purification processes are complex. The alkali leaching method has a good recovery effect on silicon-aluminum materials, but the recovery efficiency of valuable metals is low.

[0005] Therefore, we propose a method for resource treatment of silicon-aluminum-based waste catalysts to solve the problems existing in the prior art. By effectively crushing the raw materials of silicon-aluminum-based waste catalysts, the contact area between the silicon-aluminum-based waste catalysts and the reaction solvent is increased, thereby enhancing the acid-base leaching effect on the silicon-aluminum-based waste catalysts and improving the recovery efficiency of silicon-aluminum materials in the silicon-aluminum-based waste catalysts. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for resource treatment of silicon-aluminum-based waste catalysts to solve the problems in the prior art that although the traditional acid leaching method can effectively leach out valuable metals, the consumption of acid is large, the impurity content in the leaching solution is high, and the subsequent separation and purification processes are complex, and the alkali leaching method has a good recovery effect on silicon-aluminum materials, but the recovery efficiency of valuable metals is low.

[0007] To achieve the above purpose, the present invention adopts the following technical solutions:

[0008] A method for resource treatment of silicon-aluminum-based waste catalysts includes the following steps:

[0009] S1. First, the silicon-aluminum-based waste catalyst raw material is put into a crushing device to reduce the particle size of the silicon-aluminum-based waste catalyst. The crushed silicon-aluminum-based waste catalyst is screened by a screening component to separate silicon-aluminum-based waste catalysts with different particle sizes. The silicon-aluminum-based waste catalyst with larger particle size is put into the crushing device again through a circulation component for secondary crushing, thereby ensuring that the particle size of the screened silicon-aluminum-based waste catalyst is uniform;

[0010] S2. The screened silicon-aluminum-based waste catalyst particles are sequentially passed through a magnetic separation component and a flotation component to separate magnetic metal impurities and other non-magnetic impurities, and then the silicon-aluminum-based waste catalyst after impurity removal is dried to complete the raw material pretreatment of the silicon-aluminum-based waste catalyst;

[0011] S3, putting the silicon-aluminum-based waste catalyst into an acid solution for stirring to leach valuable metals, and then separating the solid and liquid in the solution, and obtaining aluminum oxide and metal elements by adjusting the pH value of the solution and performing solvent extraction;

[0012] S4. The solid residue after acid leaching is placed in an alkaline solution for stirring. After the alkaline leaching, the solution is filtered and the pH value of the alkaline solution after filtration is adjusted to precipitate aluminate. The aluminate is taken out for washing and drying.

[0013] Furthermore, the crushing device described in step S1 includes a circulation box, two sets of crushing rollers rotating in opposite directions, and a driving assembly for driving the two sets of crushing rollers, and the two sets of crushing rollers quickly crush the silicon-aluminum-based waste catalysts put in, and the crushed silicon-aluminum-based waste catalysts fall on the screening assembly;

[0014] The screening assembly includes a screen, a vibration motor and a buffer structure arranged in the inner cavity of the circulation box. The vibration motor is installed on the lower surface of the screen. Multiple groups of buffer structures are respectively arranged at the corners of the lower surface of the screen. The screen is set at an inclined angle of 15 degrees.

[0015] Furthermore, in step S1, the buffer structure includes a pair of symmetrically arranged positioning blocks, and a limiting rod passing through the screen is arranged between the two groups of positioning blocks, and both ends of the outer sides of the limiting rod are sleeved with buffer springs that contact the positioning blocks, and the opposite ends of the two groups of buffer springs respectively contact the two sides of the screen.

[0016] Furthermore, in step S1, the circulation component includes a conical bucket for collecting the silicon-aluminum-based waste catalyst with a larger particle size, a conveying auger and a material guide pipe. The conveying auger is rotatably arranged in the inner cavity of the material guide pipe, the discharge end of the material guide pipe is arranged above the feed port of the circulation box, and the material guide pipe is fixed on the top of the conical bucket.

[0017] Further, in step S2, the magnetic separation component includes two sets of electromagnetic plates arranged below the screen. The two sets of electromagnetic plates are both arranged at an inclination angle of 45 degrees, and the two sets of electromagnetic plates are arranged in parallel. The two sets of electromagnetic plates magnetically attract metal impurities from the silicon-aluminum-based waste catalyst sieved by the screen.

[0018] Further, in step S2, the flotation component includes a stirring member located at the bottom of the circulation tank. A reagent for flotation of the silicon-aluminum-based waste catalyst is injected at the bottom of the circulation tank. The silicon-aluminum-based waste catalyst and the reagent are mixed by the stirring member, and then valuable metals and impurities in the silicon-aluminum-based waste catalyst mixture are separated.

[0019] Further, in step S3, the valuable metals separated by the magnetic separation component and the flotation component are put into an acidic solution;

[0020] The liquid-solid volume mass ratio of the acidic solution to the valuable metals is controlled at 3 - 5:1, the leaching temperature is 80 - 100 °C, the stirring speed is 200 - 300 revolutions per minute, and the leaching time is 2 - 4 h, so that the valuable metals are dissolved into the solution.

[0021] Further, in step S3, the acidic solution separates the leaching solution and solid impurities through a filter screen;

[0022] An alkaline solution is added to the leaching solution to form aluminum hydroxide precipitate of aluminum in the solution. An organic solvent is added to the solution after filtering out aluminum hydroxide, and centrifugal mixing is carried out, so that the solution containing valuable metals and the solution of metal ions are layered.

[0023] Further, in step S4, the acid-leached silicon-aluminum-based waste catalyst is put into an alkaline solution;

[0024] The temperature of the alkaline solution is controlled at 100 - 150 °C, the liquid-solid ratio is 4 - 6:1, and the leaching time is 3 - 6 h to obtain sodium silicate and sodium meta-aluminate. An appropriate amount of acid solution is added to the solution after alkali leaching, so that silicate is precipitated.

[0025] Further, in step S4, the precipitated silicate is washed to remove adsorbed impurity ions on the surface, and the silicate is dried. The drying temperature is 100 - 150 °C, and the drying time is 4 - 8 h.

[0026] A resource treatment method for silicon-aluminum-based waste catalyst proposed by the present invention has the following advantages compared with the prior art:

[0027] 1. The structural arrangement of the crushing device, the screening component and the circulation component of the present invention can screen out the silicon-aluminum-based waste catalyst raw materials with appropriate particle sizes through the screening component, and collect the silicon-aluminum-based waste catalyst raw materials with larger particle sizes, and can re-transport the silicon-aluminum-based waste catalyst raw materials with larger particle sizes to the crushing device through the circulation component, and then perform secondary crushing treatment, so that the crushed silicon-aluminum-based waste catalyst raw materials have uniform particle sizes, thereby ensuring the contact area between the silicon-aluminum-based waste catalyst raw materials and the reaction solvent, and improving the recovery efficiency of silicon-aluminum materials and valuable metals in the silicon-aluminum-based waste catalyst;

[0028] 2. The acid leaching and alkali leaching methods of the present invention can efficiently dissolve the valuable metals into the solution, laying the foundation for the subsequent separation and extraction of alumina and metal elements, realizing the preliminary enrichment and separation of valuable metals, and at the same time, the silicon and aluminum in the residue can be converted into sodium silicate and sodium aluminate, and then the aluminosilicate is precipitated by adjusting the pH value, and finally the reusable silicon and aluminum material is obtained by washing and drying, which not only realizes the recovery of silicon and aluminum resources, but also improves the comprehensive utilization rate of the entire waste catalyst resource treatment, and reduces waste emissions and environmental pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a flowchart of the crushing process of the silicon-aluminum-based waste catalyst of the present invention;

[0030] Figure 2 This is a process diagram of acid-base leaching of silicon-aluminum-based waste catalysts of the present invention;

[0031] Figure 3 It is a structural block diagram of the crushing device of the present invention. DETAILED DESCRIPTION

[0032] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0033] The present invention provides Figure 1-2 A method for recycling silicon-aluminum-based waste catalysts shown in the figure comprises the following steps:

[0034] S1. First, the silicon-aluminum-based waste catalyst raw material is put into a crushing device to reduce the particle size of the silicon-aluminum-based waste catalyst. The crushed silicon-aluminum-based waste catalyst is screened by a screening component to separate silicon-aluminum-based waste catalysts with different particle sizes. The silicon-aluminum-based waste catalyst with larger particle size is put into the crushing device again through a circulation component for secondary crushing, thereby ensuring that the particle size of the screened silicon-aluminum-based waste catalyst is uniform;

[0035] S2. The screened silicon-aluminum-based waste catalyst particles are sequentially passed through a magnetic separation component and a flotation component to separate magnetic metal impurities and other non-magnetic impurities, and then the silicon-aluminum-based waste catalyst after impurity removal is dried to complete the raw material pretreatment of the silicon-aluminum-based waste catalyst;

[0036] S3, putting the silicon-aluminum-based waste catalyst into an acid solution for stirring to leach valuable metals, and then separating the solid and liquid in the solution, and obtaining aluminum oxide and metal elements by adjusting the pH value of the solution and performing solvent extraction;

[0037] S4. The solid residue after acid leaching is placed in an alkaline solution for stirring. After the alkaline leaching, the solution is filtered and the pH value of the alkaline solution after filtration is adjusted to precipitate aluminate. The aluminate is taken out for washing and drying.

[0038] The crushing device described in step S1 includes a circulation box, two groups of crushing rollers rotating in opposite directions, and a driving assembly driving the two groups of crushing rollers. The two groups of crushing rollers quickly crush the silicon-aluminum-based waste catalysts that are put in. The crushed silicon-aluminum-based waste catalysts fall on the screening assembly. The silicon-aluminum-based waste catalysts are put in through the feed port on the circulation box. The two groups of crushing rollers are driven by the driving assembly to effectively crush the silicon-aluminum-based waste catalysts, reduce the particle size of the silicon-aluminum-based waste catalysts, so that the crushed silicon-aluminum-based waste catalysts can be preliminarily screened by the screening assembly to separate silicon-aluminum-based waste catalysts of different sizes.

[0039] The screening component includes a screen, a vibration motor and a buffer structure arranged in the inner cavity of the circulation box. The vibration motor is installed on the lower surface of the screen, and multiple groups of buffer structures are respectively arranged at the corners of the lower surface of the screen. The screen is set at an inclined angle of 15 degrees, and the screen is driven by the vibration motor to vibrate, thereby accelerating the separation efficiency of the silicon-aluminum-based waste catalyst on the screen, so that the silicon-aluminum-based waste catalyst with smaller particle size falls through the sieve holes on the screen, and the silicon-aluminum-based waste catalyst with larger particle size enters the circulation component through the outlet on one side of the circulation box.

[0040] In step S1, the buffer structure includes a pair of symmetrically arranged positioning blocks, and a limiting rod penetrating the screen is arranged between the two groups of positioning blocks, and both ends of the outer sides of the limiting rod are sleeved with buffer springs that are in contact with the positioning blocks, and the opposite ends of the two groups of buffer springs are in contact with the two sides of the screen respectively. The moving direction of the vibration of the screen is restricted by multiple groups of limiting rods, thereby ensuring that the silicon-aluminum-based waste catalyst can move in one direction, so as to collect silicon-aluminum-based waste catalysts with larger particle sizes, thereby improving the screening efficiency of silicon-aluminum-based waste catalysts.

[0041] In step S1, the circulation component includes a conical bucket for collecting the silicon-aluminum-based waste catalysts with larger particle sizes, a conveying auger and a guide pipe. The conveying auger is rotatably arranged in the inner cavity of the guide pipe, and the discharge end of the guide pipe is arranged above the feed port of the circulation box. The guide pipe is fixed on the top of the conical bucket. The collected silicon-aluminum-based waste catalysts with larger particle sizes can be gathered through the conical bucket and transported along the guide pipe under the action of the conveying auger, and enter the circulation box through the discharge port on the guide pipe, and are crushed for the second time by two sets of crushing rollers, thereby re-crushing the silicon-aluminum-based waste catalysts with larger particle sizes, thereby improving the crushing effect of the silicon-aluminum-based waste catalysts, so that the particle size of the silicon-aluminum-based waste catalysts is uniform and convenient for reacting with the solution.

[0042] In step S2, the magnetic separation component includes two groups of electromagnetic plates arranged below the screen, the two groups of electromagnetic plates are arranged at an inclination angle of 45 degrees, and the two groups of electromagnetic plates are arranged in parallel. The two groups of electromagnetic plates magnetically absorb metal impurities from the silicon-aluminum-based waste catalyst under the screen. When the electromagnetic plates are energized, magnetism is generated to adsorb metal impurities in the crushed silicon-aluminum-based waste catalyst, thereby reducing the impact of impurities on subsequent valuable metal extraction and improving the purity of valuable metal extraction.

[0043] In step S2, the flotation assembly includes a stirring member located at the bottom of the circulation box, and a reagent for flotation of the silicon-aluminum-based waste catalyst is injected into the bottom of the circulation box. An appropriate amount of water is added to the crushed waste catalyst powder to prepare a certain concentration of slurry, and the slurry concentration is controlled at 20%-40% (mass fraction). Then, a regulator is added to adjust the pH value of the slurry to a suitable range, and a collector and a frother are added in a certain order. The collector is first added and stirred for a period of time so that the collector is fully adsorbed on the surface of the target mineral. The general stirring time is 3-5 minutes. Then the frother is added and stirred for 1-2 minutes to generate a large number of uniform and stable bubbles in the slurry, so that the bubbles in the slurry are fully in contact with the particles, and the hydrophobic target mineral particles are attached to the bubbles and float to the surface of the slurry with the bubbles to form a foam layer, while the hydrophilic impurity particles remain in the slurry, and the foam layer is scraped out by a scraper to obtain a concentrate containing the target mineral, and the tailings are left at the bottom of the flotation tank, thereby realizing the separation of impurities and valuable components.

[0044] In step S3, the valuable metals separated by the magnetic separation component and the flotation component are put into an acidic solution;

[0045] The liquid-solid volume-mass ratio of the acidic solution to the valuable metals is controlled at 3-5:1, the leaching temperature is 80-100 °C, the stirring speed is 200-300 revolutions per minute, and the leaching time is 2-4 h. The valuable metals are dissolved into the solution. By using the chemical reaction between the acid and the metal oxides or salts in the waste catalyst, metal ions are dissolved into the solution, which has a high leaching rate for various valuable metals and can effectively separate the metals from the silicon-aluminum matrix, providing a good basis for subsequent separation and purification.

[0046] In step S3, the acidic solution separates the leaching solution from the solid impurities through a filter screen. Filtration is a physical method to separate insoluble solids from the leaching solution. Flocculation precipitation is to add a flocculant to make tiny suspended particles aggregate to form larger particles, thus accelerating precipitation separation. It can effectively improve the purity of the leaching solution, create favorable conditions for the subsequent separation and purification of valuable metals, reduce the interference of impurities on the separation process, and improve the product quality;

[0047] An alkaline solution is added to the leaching solution to form aluminum hydroxide precipitate of the aluminum in the solution. After the aluminum hydroxide is filtered out, the solution is put into an organic solvent for centrifugal mixing, so that the solution containing valuable metals is layered from the solution of metal ions. Adjusting the pH value to make aluminum ions form aluminum hydroxide precipitate makes use of the amphoteric property of aluminum hydroxide and controls the acidity and alkalinity of the solution to reach the precipitation condition. It can achieve efficient separation and purification according to the properties of different metals, obtain high-purity valuable metal products, and improve the economic benefits of resource recovery.

[0048] In step S4, the acid-leached silicon-aluminum-based waste catalyst is put into an alkaline solution. The aluminosilicate reacts with sodium hydroxide to form soluble sodium silicate and sodium aluminate, transferring silicon and aluminum from the solid residue to the solution;

[0049] The temperature of the alkaline solution is controlled at 100-150 °C, the liquid-solid ratio is 4-6:1, and the leaching time is 3-6 h to obtain sodium silicate and sodium aluminate. An appropriate amount of acid solution is added to the solution after alkali leaching, so that the aluminosilicate precipitates out. Adjusting the pH value makes the aluminosilicate precipitate out again. By using the solubility difference of aluminosilicate at different pH values and controlling the pH value to reach the supersaturated state for precipitation, the precipitation recovery of silicon-aluminum materials can be realized through simple pH adjustment. The operation is relatively simple, and the particle size and morphology of the precipitate can be controlled according to needs, which is beneficial to the application of subsequent products.

[0050] In step S4, the precipitated aluminosilicate is washed to remove the impurity ions adsorbed on the surface, and the aluminosilicate is dried. The drying temperature is 100-150°C, and the drying time is 4-8h. Washing is to remove the impurity ions adsorbed on the surface of the precipitate and improve the product purity. Drying is to remove moisture and obtain a dry aluminosilicate material product, which is convenient for storage and reuse.

[0051] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for recycling silicon-aluminum-based waste catalysts, comprising the following steps: S1. First, the silicon-aluminum-based waste catalyst raw material is put into a crushing device to reduce the particle size of the silicon-aluminum-based waste catalyst. The crushed silicon-aluminum-based waste catalyst is screened by a screening component to separate silicon-aluminum-based waste catalysts with different particle sizes. The silicon-aluminum-based waste catalyst with larger particle size is put into the crushing device again through a circulation component for secondary crushing, thereby ensuring that the particle size of the screened silicon-aluminum-based waste catalyst is uniform; S2. The screened silicon-aluminum-based waste catalyst particles are sequentially passed through a magnetic separation component and a flotation component to separate magnetic metal impurities and other non-magnetic impurities, and then the silicon-aluminum-based waste catalyst after impurity removal is dried to complete the raw material pretreatment of the silicon-aluminum-based waste catalyst; S3, putting the silicon-aluminum-based waste catalyst into an acid solution for stirring to leach valuable metals, and then separating the solid and liquid in the solution, and obtaining aluminum oxide and metal elements by adjusting the pH value of the solution and performing solvent extraction; S4. The solid residue after acid leaching is placed in an alkaline solution for stirring. After the alkaline leaching, the solution is filtered and the pH value of the alkaline solution after filtration is adjusted to precipitate aluminate. The aluminate is taken out for washing and drying.

2. The method for recycling silicon-aluminum-based waste catalyst according to claim 1, characterized in that: The crushing device in step S1 includes a circulation box, two sets of crushing rollers rotating in opposite directions, and a driving assembly for driving the two sets of crushing rollers. The two sets of crushing rollers quickly crush the silicon-aluminum-based waste catalysts, and the crushed silicon-aluminum-based waste catalysts fall onto the screening assembly. The screening assembly includes a screen, a vibration motor and a buffer structure arranged in the inner cavity of the circulation box. The vibration motor is installed on the lower surface of the screen. Multiple groups of buffer structures are respectively arranged at the corners of the lower surface of the screen. The screen is set at an inclined angle of 15 degrees.

3. The method for recycling silicon-aluminum-based waste catalyst according to claim 2, characterized in that: In step S1, the buffer structure includes a pair of symmetrically arranged positioning blocks, and a limiting rod penetrating the screen is arranged between the two groups of positioning blocks. Both ends of the outer sides of the limiting rod are sleeved with buffer springs that abut against the positioning blocks, and the opposite ends of the two groups of buffer springs respectively abut against the two sides of the screen.

4. The method for recycling silicon-aluminum-based waste catalyst according to claim 3, characterized in that: In step S1, the circulation component includes a conical bucket for collecting silicon-aluminum-based waste catalysts with larger particle sizes, a conveying auger and a material guide pipe. The conveying auger is rotatably arranged in the inner cavity of the material guide pipe, the discharge end of the material guide pipe is arranged above the feed port of the circulation box, and the material guide pipe is fixed on the top of the conical bucket.

5. The method for recycling silicon-aluminum-based waste catalyst according to claim 4, characterized in that: In step S2, the magnetic separation assembly includes two groups of electromagnetic plates arranged below the screen, the two groups of electromagnetic plates are arranged at an angle of 45 degrees, and the two groups of electromagnetic plates are arranged in parallel, and the two groups of electromagnetic plates magnetically absorb metal impurities from the silicon-aluminum-based waste catalyst under the screen.

6. The method for recycling silicon-aluminum-based waste catalyst according to claim 5, characterized in that: In step S2, the flotation assembly includes a stirring member located at the bottom of the circulation box, and a reagent for flotation of the silicon-aluminum-based waste catalyst is injected into the bottom of the circulation box. The silicon-aluminum-based waste catalyst and the reagent are mixed by the stirring member, thereby separating the valuable metals and impurities in the silicon-aluminum-based waste catalyst mixed liquid.

7. The method for recycling silicon-aluminum-based waste catalyst according to claim 6, characterized in that: In step S3, the valuable metals separated by the magnetic separation component and the flotation component are added to the acidic solution; The liquid-solid mass ratio of the acid solution to the valuable metals is controlled at 3-5:1, the leaching temperature is 80-100°C, the stirring speed is 200-300 rpm, the leaching time is 2-4h, and the valuable metals are dissolved into the solution.

8. The method for recycling silicon-aluminum-based waste catalyst according to claim 1, characterized in that: In step S3, the acidic solution is passed through a filter to separate the leachate from the solid impurities; An alkaline solution is added to the leaching solution to make the aluminum in the solution generate aluminum hydroxide precipitate, and the solution after the aluminum hydroxide is filtered out is added to an organic solvent for centrifugal mixing, so that the solution containing the valuable metal and the solution of the metal ion are separated into layers.

9. The method for recycling silicon-aluminum-based waste catalyst according to claim 1, characterized in that: In step S4, the acid-leached silicon-aluminum-based waste catalyst is placed in an alkaline solution; The temperature of the alkaline solution is controlled at 100-150°C, the liquid-to-solid ratio is 4-6:1, and the leaching time is 3-6 hours to obtain sodium silicate and sodium aluminate. An appropriate amount of acid solution is added to the solution after alkali leaching to precipitate aluminosilicate.

10. The method for recycling silicon-aluminum-based waste catalyst according to claim 1, characterized in that: In step S4, the precipitated aluminosilicate is washed to remove impurity ions adsorbed on the surface, and the aluminosilicate is dried at a drying temperature of 100-150° C. for a drying time of 4-8 hours.

Images