Method and device for preparing fly ash-based zeolite molecular sieve by hypergravity intensification premixing

Abstract

The application aims to provide a method and device for preparing fly ash-based zeolite molecular sieve by supergravity intensification, and belongs to the technical field of high value-added utilization of fly ash.The silicon and aluminum raw materials contained in fly ash are subjected to alkali melting and acid leaching to obtain alumina and sodium silicate solution, which are mixed with NaOH and H2O respectively according to a ratio, enter an impinging stream-rotating packed bed for premixing, and then are crystallized in a high-pressure hydrothermal reaction kettle, so as to obtain fly ash-based zeolite molecular sieve with high purity and uniform particle size.The application fully mixes the raw materials on the basis of reducing the amount of packing by half, reduces the loss of raw materials while shearing and crushing the raw materials, shortens the mixing time of raw materials in the preparation of fly ash-based molecular sieve, improves the utilization rate of fly ash, increases the high value-added utilization of fly ash, and is beneficial to realize the industrialized production of fly ash for preparing molecular sieve.

Description

Technical Field

[0001] This invention belongs to the field of high-value-added utilization technology of fly ash, specifically relating to a method and apparatus for preparing fly ash-based zeolite molecular sieves by supergravity-enhanced premixing. Background Technology

[0002] Fly ash is an industrial solid waste produced from coal combustion, with its main phases being quartz and mullite. As coal remains my country's primary energy source, fly ash production has been steadily increasing in recent years, making its recycling a pressing issue. Fly ash is commonly used in the preparation of concrete, geopolymers, and building materials, primarily in low-value applications.

[0003] The high-value utilization of fly ash includes the preparation of ceramic materials, silicon and aluminum extraction, and the preparation of molecular sieves. Molecular sieves are artificially synthesized aluminosilicate crystals with regular micropores, possessing ion exchange, adsorption, and catalytic properties, and are widely used in petrochemical, wastewater, and waste gas treatment fields. The main components of fly ash are Al2O3 and SiO2, with a chemical composition similar to that of molecular sieves, making the preparation of molecular sieves from fly ash structurally feasible. The silicon and aluminum sources used for molecular sieve synthesis are inorganic chemicals, typically obtained from natural silicon and aluminum minerals such as quartz and bauxite through complex reaction and separation processes, accompanied by significant energy and material consumption and pollution emissions. Due to the increasingly wide range of applications for molecular sieves, the growing demand necessitates further reductions in their production costs. Therefore, using fly ash as a raw material for synthesizing molecular sieves can reduce synthesis costs, minimize environmental damage, effectively solve the problem of fly ash reuse, and achieve high-value applications of fly ash.

[0004] The main methods for synthesizing molecular sieves from fly ash include hydrothermal synthesis, two-step hydrothermal synthesis, seed crystal introduction, and alkali melting-hydrothermal synthesis. However, the hydrothermal synthesis process is time-consuming, and traditional stirred reactors suffer from problems such as low mass transfer rate, low micro-mixing efficiency, uneven product particle size distribution, and long aging time. Hypergravity technology, as a method to enhance mass transfer, involves two fluid streams entering from two inlets in an impacting flow-rotating packed bed. These streams then exit through nozzles, forming jets that collide and create a circular (fan-shaped) mist surface perpendicular to the jet direction, completing the mixing process. The weaker-mixed edge of the impacting mist surface enters the inner cavity of the rotating packed bed, flowing along the packing pores towards the outer edge. During this process, the fluid is repeatedly cut, condensed, and dispersed, thus greatly enhancing the mass transfer rate and micro-mixing process. In the rotating packed bed, the liquid collides with the high-speed rotating packing, undergoing continuous breaking and coalescence, resulting in high dispersion and rapid phase interface renewal. This significantly enhances micro-mixing, increases liquid turbulence, and strengthens the mass transfer process. By leveraging the extremely rapid micro-mixing capabilities of hypergravity technology, hypergravity premixing can enhance the necessary conditions for achieving uniformity in the early stages of crystal nucleus formation. This effectively reduces premixing time, saves production costs, and produces high-performance molecular sieve products.

[0005] The silicon and aluminum sources enter the impinging flow-rotating packed bed and collide head-on to complete the initial mixing, forming a precursor gel solution. After being circulated and re-entering the rotating packed bed, a large amount of gel solution residue is caused in the traditional integrated packed bed device, which greatly reduces the utilization rate of raw materials.

[0006] Currently, there are many reports on the preparation of molecular sieves from fly ash in my country, but there are few studies on the preparation of fly ash-based molecular sieves by supergravity premixing and hydrothermal method. In particular, there are no reports on the preparation of fly ash-based molecular sieves by using supergravity-enhanced premixing. Applying supergravity to the premixing of fly ash-based molecular sieves will greatly shorten the aging process and improve the economic benefits of synthesized molecular sieves. Summary of the Invention

[0007] To address the aforementioned problems, the present invention aims to provide a method and apparatus for preparing fly ash-based zeolite molecular sieves using enhanced premixing under high gravity. The high gravity apparatus provided by this invention effectively reduces the amount of packing material used while significantly minimizing raw material loss. In this invention, the silica-alumina source obtained from fly ash through alkali fusion and acid leaching is mixed with NaOH and H2O respectively, and then premixed in an impinging flow-rotating packed bed with a special packing device. The mixture is then crystallized in a high-pressure reactor to prepare fly ash-based zeolite molecular sieves. This method ensures reduced raw material loss while improving premixing efficiency, significantly shortening the aging time for preparing the molecular sieves.

[0008] The present invention adopts the following technical solution:

[0009] A method for preparing fly ash-based zeolite molecular sieves using ultragravity-enhanced premixing includes the following steps:

[0010] (1) Fly ash and alkali additive are mixed and roasted to obtain clinker;

[0011] (2) Grind and sieve the cooled clinker;

[0012] (3) The clinker obtained in step (2) is mixed with acid and then heated and stirred in a water bath.

[0013] (4) The product obtained in step (3) is centrifuged to obtain crude silica gel and crude aluminum chloride solution, which are then purified to obtain pure aluminum hydroxide and sodium silicate solution.

[0014] (5) The aluminum hydroxide obtained in step (4) is mixed with H2O and NaOH in a certain proportion to obtain an aluminum source. The sodium silicate solution is mixed with NaOH in a certain proportion to obtain a silicon source. The aluminum source and silicon source are transferred into an impinging flow-rotating packed bed for premixing, and the feed rate is controlled at 200~600 mL·min. -1 The rotational speed is 1800~2800 r·min -1 The liquid flow rate is 30~50 L·h -1 The cycle time is 10~30 min to obtain the precursor gel solution;

[0015] (6) The precursor gel solution obtained in step (5) is hydrothermally crystallized. After crystallization, the product is filtered, washed until neutral, and dried to obtain a fly ash-based molecular sieve sample.

[0016] (7) The prepared fly ash-based molecular sieve sample was used to adsorb lead-containing wastewater (each 1g of molecular sieve sample adsorbed 50mL of lead-containing wastewater at a concentration of 500 mg·L⁻¹). -1 (lead-containing wastewater).

[0017] Further, the alkali additive mentioned in step (1) is Na2CO3, the ash-alkali ratio of fly ash and Na2CO3 is 1:1.25~1.75, the calcination temperature is 800℃, and the calcination time is 3h.

[0018] Furthermore, in step (2), the grinding and sieving process uses a 200-mesh sieve.

[0019] Furthermore, the acid mentioned in step (3) is HCl, the water bath heating temperature is 80℃, the reaction time is 3h, and the hydrochloric acid concentration is 3~5 mol•L. -1 Add 10 mL of HCl to every 1 g of cooked material at a ratio of 1:10.

[0020] Furthermore, in step (5), the molar ratio of aluminum hydroxide to NaOH and H2O is 2:7:150, and the molar ratio of sodium silicate and H2O to NaOH in the sodium silicate solution is: sodium silicate:NaOH:H2O=2.8:2.56:150.

[0021] Furthermore, in step (5), the silicon source and the aluminum source are mixed in equal volumes.

[0022] Furthermore, the hydrothermal crystallization temperature in step (6) is 105°C and the time is 12h, and the drying temperature is 100°C and the time is 12h.

[0023] Furthermore, the impinging flow-rotating packed bed includes an impinging flow device and a rotating packed bed; the rotating packed bed has a horizontal structure; the impinging flow device is located in the middle of one side of the shell of the rotating packed bed, including a first feed pipe and a second feed pipe, which are respectively connected to storage tank I and storage tank II via peristaltic pump I and peristaltic pump II, respectively. The nozzles of the first feed pipe and the second feed pipe have a convection structure. The silicon source and the aluminum source enter simultaneously from storage tank I and storage tank II and then undergo impinging spraying. The bottom of the shell of the rotating packed bed is provided with a liquid outlet, which is connected to storage tank III. After the liquid is mixed, it forms a precursor gel solution that flows into storage tank III and continues to enter the rotating packed bed through peristaltic pump III to complete the circulation. The shell is equipped with an annular packing device.

[0024] Furthermore, the annular packing device includes a rotor with an outer wire mesh. The rotor has an inner-outer diameter ratio of 1:3. Inside the rotor is a packing layer with a stainless steel mesh structure and Pall ring packing. When the precursor gel solution passes through the packing device, it collides and undergoes continuous shearing to achieve high dispersion, followed by further aggregation. This greatly enhances the micro-mixing process, thus achieving the necessary conditions for uniformity in the early stages of crystal nucleation and effectively reducing premixing time. The packing is divided into four equal layers, each layer evenly divided into eight parts, with four parts of packing spaced apart. From the inside out, the first and third layers of packing are in the same position, and the second and fourth layers are in the same position. The amount of Pall ring packing is reduced by half, resulting in less gel solution adhering to the packing and a significantly lower raw material loss rate. The orderly placement of the Pall ring packing in different positions ensures effective mixing of the precursor gel solution while reducing its quantity.

[0025] Furthermore, the outer wire mesh of the annular packing device is equipped with eight scrapers of the same height as the packing device, with a width equal to the distance between the outer layer of the packing and the inner wall of the rotating packing bed. The oblique angle between the scraper and the outer layer of the packing is 30~60°. The scrapers are wear-resistant silicone scrapers or plastic scrapers. The precursor gel solution is thrown by the packing device to the inner wall of the shell and flows into the outlet, while part of the gel solution adhering to the inner wall is discharged into the outlet by the scrapers as the packing device rotates, thus achieving circulation.

[0026] The fly ash-based zeolite molecular sieve is used in the treatment of lead-containing wastewater.

[0027] The beneficial effects of this invention are as follows:

[0028] This invention combines centrifugal technology with the preparation of fly ash-based zeolite molecular sieves. First, fly ash is treated to obtain a silica-alumina source, which is then premixed using an impinging flow-rotating packed bed. After hydrothermal treatment, fly ash-based zeolite molecular sieves are obtained. By utilizing the enhanced mixing characteristics of centrifugal technology, rapid and efficient preparation of fly ash-based molecular sieves is achieved.

[0029] 1. This invention uses fly ash as raw material and employs a high-gravity enhanced premixing method to prepare fly ash-based zeolite molecular sieves. Fly ash and Na₂CO₃ are mixed and calcined to obtain clinker; the clinker is mixed with acid for a period of time and then centrifuged to obtain silicon-aluminum sources; a novel high-gravity device is designed to premix the obtained silicon-aluminum sources with H₂O and NaOH in an impinging flow-rotating packed bed, shortening the aging time, reducing raw material loss, and improving raw material utilization, thereby obtaining fly ash-based zeolite molecular sieves with high purity and uniform particle size.

[0030] 2. The preparation method provided by this invention is simple and has low requirements. It uses ultragravity premixing + hydrothermal method to prepare fly ash-based zeolite molecular sieves, which improves the utilization rate of fly ash, increases the high added value of fly ash, turns fly ash into a treasure, and greatly improves economic benefits. Attached Figure Description

[0031] Figure 1 This is a process flow diagram of the present invention.

[0032] Figure 2 A schematic diagram of the premixing process for an impinging flow-rotating packed bed.

[0033] Figure 3 This is a top view of the packing device in the supergravity device of the present invention.

[0034] Figure 4 This is the XRD pattern of fly ash.

[0035] Figure 5 The infrared spectrum of the molecular sieve sample prepared in Example 1 of the present invention is shown.

[0036] Figure 6 The image shows the XRD pattern of the fly ash-based molecular sieve sample prepared according to the present invention.

[0037] In the figure, 1-storage tank I; 2-peristaltic pump I; 3-liquid flow meter I; 4-peristaltic pump II; 5-liquid flow meter II; 6-storage tank II; 7-peristaltic pump III; 8-liquid flow meter III; 9-impact flow-rotating packed bed; 10-storage tank III; 11-scraper; 12-Pall ring packing; 13-blank packing. Detailed Implementation

[0038] The specific embodiments are described in detail below with reference to the accompanying drawings. It should be noted that the content of the present invention is not limited to the following embodiments.

[0039] This invention relates to a method for preparing fly ash-based zeolite molecular sieves based on centrifugal premixing and hydrothermal method, the process flow of which is as follows: Figure 1 As shown: After high-temperature roasting, the raw material fly ash is subjected to alkali melting, acid leaching, purification, ultra-gravity premixing, and hydrothermal reaction to obtain molecular sieve products.

[0040] Example 1

[0041] Preparation of fly ash-based zeolite molecular sieves by supergravity premixing and hydrothermal method

[0042] The fly ash raw material comes from a power generation company, and the chemical composition of the fly ash is shown in Table 1.

[0043] Table 1 Chemical composition of fly ash

[0044]

[0045] Take 10.00 g of fly ash and 12.5 g of Na2CO3 (ash-alkali ratio of 1.25) and mix them evenly in a corundum crucible. Melt the mixture at 800℃ for 3 h to obtain clinker. Grind the cooled clinker through a 200-mesh sieve.

[0046] Take 20 g of clinker and 200 mL of 3 mol·L⁻¹ solution. -1 The mixture of hydrochloric acid and silica gel (liquid-to-solid ratio 10) was placed in a constant temperature water bath and heated to 80°C with stirring for 3 hours. After centrifugation, crude silica gel and crude aluminum chloride solutions were obtained. The separated silica-alumina sources were purified to obtain pure aluminum hydroxide and sodium silicate solutions.

[0047] According to the specified proportions, aluminum hydroxide and sodium silicate solutions were added to H₂O and NaOH, respectively. The aluminum source was dissolved in storage tank I, and the silicon source was dissolved in storage tank II. The two liquids of equal volume were injected at a rate of 200 mL / min. -1 The feed rate is such that the feed particles collide head-on in the impinging flow-rotating packed bed, and after mixing, they flow into the storage tank III. The peristaltic pump III then controls the liquid flow rate to 30 L·h. -1 The mixture enters the rotating packed bed and undergoes shearing and mixing via the packing device, which rotates at 1800 r / min.-1 After cycling for 10 min, the obtained precursor was placed in a 100 mL hydrothermal reactor and crystallized at 105 °C for 12 h. The reactants were washed until neutral and dried at 100 °C for 12 h to obtain the molecular sieve sample.

[0048] Add 50 mL of 500 mg·L⁻¹ to each 1 g of molecular sieve sample. -1 The lead-containing wastewater was adsorbed, and the lead ion concentration was then determined by atomic spectrophotometry. The removal rate of lead-containing wastewater was found to be 62.08%.

[0049] Infrared characterization was performed on the functional groups of Example 1, and the results are as follows: Figure 5 As shown, at 3445 cm ‑1 The broad absorption peak at 1632 cm⁻¹ is attributed to the stretching vibration of the -OH groups on the surface of the water adsorbed by the molecular sieve. ‑1 The absorption peak at this location is the bending vibration peak of the -OH group of adsorbed water, at 984 cm⁻¹. -1 The absorption peak at 744 cm⁻¹ is the asymmetric stretching vibration peak of the TOT (T = Si, Al) tetrahedron inside the molecular sieve. -1 And 674cm -1 Absorption peaks for both symmetric and asymmetric stretching vibrations of the molecular sieve framework appeared at 561 cm⁻¹. -1 The presence of characteristic peaks of double rings in the molecular sieve structure indicates the formation of four-membered rings in the structure. The [SiO4] and [AlO4] tetrahedra in the framework structure recombine to form the molecular sieve framework structure, confirming the formation of a molecular sieve sample.

[0050] Example 2

[0051] Take 10.00 g of fly ash and 15 g of Na2CO3 (ash-alkali ratio of 1.5) and mix them evenly in a corundum crucible. Melt the mixture at 800℃ for 3 h to obtain clinker. Grind the cooled clinker through a 200-mesh sieve.

[0052] Take 20 g of clinker and 200 mL of 4 mol·L⁻¹ solution. -1 The mixture of hydrochloric acid and silica gel (liquid-to-solid ratio 10) was placed in a constant temperature water bath and heated to 80°C with stirring for 3 hours. After centrifugation, crude silica gel and crude aluminum chloride solutions were obtained. The separated silica-alumina sources were purified to obtain pure aluminum hydroxide and sodium silicate solutions.

[0053] According to the specified proportions, aluminum hydroxide and sodium silicate solutions were added to H₂O and NaOH, respectively. The aluminum source was dissolved in storage tank I, and the silicon source was dissolved in storage tank II. The two liquids of equal volume were injected at a rate of 400 mL / min. -1The feed rate is such that the feed particles collide head-on in the impinging flow-rotating packed bed, and after mixing, they flow into the storage tank III. The peristaltic pump III then controls the liquid flow rate to 40 L·h. -1 The mixture enters the rotating packed bed and undergoes shearing and mixing via the packing device, which rotates at 2300 r / min. -1 After circulating for 20 min, the mixture was placed in a 100 mL hydrothermal reactor and crystallized at 105 °C for 12 h. The reactants were washed until neutral and dried at 100 °C for 12 h to obtain the molecular sieve sample.

[0054] Add 50 mL of 500 mg·L⁻¹ to each 1 g of molecular sieve sample. -1 The lead-containing wastewater was adsorbed, and the lead ion concentration was then determined by atomic spectrophotometry. The removal rate of lead-containing wastewater was found to be 75.11%.

[0055] Example 3

[0056] Take 10.00 g of fly ash and 17.5 g of Na2CO3 (ash-alkali ratio of 1.75) and mix them evenly in a corundum crucible. Melt the mixture at 800℃ for 3 h to obtain clinker. Grind the cooled clinker through a 200-mesh sieve.

[0057] Take 20 g of cooked material and 200 mL of 5 mol·L⁻¹ solution. -1 The mixture of hydrochloric acid and silica gel (liquid-to-solid ratio 10) was placed in a constant temperature water bath and heated to 80°C with stirring for 3 hours. After centrifugation, crude silica gel and crude aluminum chloride solutions were obtained. The separated silica-alumina sources were purified to obtain pure aluminum hydroxide and sodium silicate solutions.

[0058] According to the specified proportions, aluminum hydroxide and sodium silicate solutions were added to H₂O and NaOH, respectively. The aluminum source was dissolved in storage tank I, and the silicon source was dissolved in storage tank II. The two liquids of equal volume were mixed at a rate of 600 mL / min. -1 The feed rate is such that the feed particles collide head-on in the impinging flow-rotating packed bed, and after mixing, they flow into the storage tank Ⅲ. The peristaltic pump 3 then controls the liquid flow rate to be 50 L·h. -1 The mixture enters the rotating packed bed and undergoes shearing and mixing via the packing device, which rotates at 2800 r / min. -1 After circulating for 30 min, the mixture was placed in a 100 mL hydrothermal reactor and crystallized at 105 °C for 12 h. The reactants were washed until neutral and dried at 100 °C for 12 h to obtain the molecular sieve sample.

[0059] Add 50 mL of 500 mg·L⁻¹ to each 1 g of molecular sieve sample. -1The lead-containing wastewater was adsorbed, and the lead ion concentration was then determined by atomic spectrophotometry. The removal rate of lead-containing wastewater was found to be 85.08%.

[0060] X-ray diffraction was performed on the three fly ash-based molecular sieve samples prepared in the examples, and the results are as follows: Figure 6 As shown, compared with the NaX standard card (PDF#38-0237), all three molecular sieve samples showed characteristic peaks of NaX-type molecular sieves, and the peak positions were consistent with those of NaX-type molecular sieves reported in the literature. The crystallinity of molecular sieves is greatly affected by the cycling time. When the cycling time is 30 min, the molecular sieve has a single crystal phase and the purity is the highest.

[0061] This invention recovers and extracts silicon and aluminum elements from fly ash, a solid waste, and prepares fly ash-based zeolite molecular sieves using a supergravity premixing + hydrothermal method. The use of supergravity technology for premixing enhances the necessary conditions for uniform crystal nuclei formation in the early stages, effectively reducing premixing time and resulting in high-purity, high-performance fly ash-based zeolite molecular sieves.

Claims

1. An apparatus for preparing fly ash-based zeolite molecular sieves using ultragravity-enhanced premixing, characterized in that: The device includes an impingement flow device and a rotating packed bed. The rotating packed bed has a horizontal structure. The impingement flow device is located in the middle of one side of the shell of the rotating packed bed and includes a first feed pipe and a second feed pipe. The first feed pipe and the second feed pipe are respectively connected to the storage tank I and the storage tank II through peristaltic pump I and peristaltic pump II, respectively. The nozzles of the first feed pipe and the second feed pipe have a convection structure. The silicon source and the aluminum source enter the storage tank I and the storage tank II simultaneously and then impinge and spray. The bottom of the shell of the rotating packed bed is provided with a liquid outlet connected to the storage tank III. After the liquid is mixed, it forms a precursor gel solution that flows into the storage tank III and continues to enter the rotating packed bed through the peristaltic pump III to complete the circulation. The shell is equipped with an annular packing device. The annular packing device includes a rotor with an outer wire mesh. The rotor has an inner-outer diameter ratio of 1:

3. Inside the rotor is a packing layer with a stainless steel mesh structure and Pall ring packing. The packing is divided into four layers in equal proportion, each layer is evenly divided into eight parts, and four parts of the packing are arranged at intervals. From the inside to the outside, the first and third layers of the packing are in the same position, and the second and fourth layers are in the same position. The first and second layers of packing are arranged alternately. The outer wire mesh of the annular packing device is equipped with eight scrapers of the same height as the packing device. The width of the scrapers is the distance between the outer layer of the packing and the inner wall of the rotating packing bed. The oblique angle between the scrapers and the outer layer of the packing is 30~60°. The scrapers are wear-resistant silicone scrapers or plastic scrapers.

2. A method for preparing fly ash-based zeolite molecular sieves using the apparatus as described in claim 1, characterized in that: Includes the following steps: (1) Fly ash and alkali additive are mixed and roasted to obtain clinker; (2) Grind and sieve the cooled clinker; (3) The clinker obtained in step (2) is mixed with acid and then heated and stirred in a water bath. (4) The product obtained in step (3) is centrifuged to obtain crude silica gel and crude aluminum chloride solution, which are then purified to obtain pure aluminum hydroxide and sodium silicate solution. (5) The aluminum hydroxide obtained in step (4) is mixed with H2O and NaOH in a certain proportion to obtain an aluminum source. The sodium silicate solution is mixed with NaOH in a certain proportion to obtain a silicon source. The aluminum source and silicon source are transferred into an impinging flow-rotating packed bed for premixing, and the feed rate is controlled at 200~600 mL·min. -1 The rotational speed is 1800~2800 r·min -1 The liquid flow rate is 30~50 L·h -1 The cycle time is 10~30 min to obtain the precursor gel solution; (6) The precursor gel solution obtained in step (5) is hydrothermally crystallized. After crystallization, the product is filtered, washed until neutral, and dried to obtain a fly ash-based molecular sieve sample. (7) The prepared fly ash-based molecular sieve sample was used to adsorb lead-containing wastewater.

3. The method for preparing fly ash-based zeolite molecular sieves using ultragravity-enhanced premixing according to claim 2, characterized in that: The alkali additive mentioned in step (1) is Na2CO3, the ash-alkali ratio of fly ash and Na2CO3 is 1:1.25~1.75, the calcination temperature is 800℃, and the calcination time is 3h.

4. The method for preparing fly ash-based zeolite molecular sieves using ultragravity-enhanced premixing according to claim 2, characterized in that: In step (2), the grinding and sieving process uses a 200-mesh sieve.

5. The method for preparing fly ash-based zeolite molecular sieves using ultragravity-enhanced premixing according to claim 2, characterized in that: The acid used in step (3) is HCl, the water bath heating temperature is 80℃, the reaction time is 3h, and the hydrochloric acid concentration is 3~5mol•L. -1 Add 10 mL of HCl to every 1 g of cooked material at a ratio of 1:

10.

6. The method for preparing fly ash-based zeolite molecular sieves using ultragravity-enhanced premixing according to claim 2, characterized in that: In step (5), the molar ratio of aluminum hydroxide to NaOH and H2O is 2:7:150, and the molar ratio of sodium silicate and H2O to NaOH in the sodium silicate solution is: sodium silicate:NaOH:H2O=2.8:2.56:150; the silicon source and aluminum source are mixed in equal volumes.

7. The method for preparing fly ash-based zeolite molecular sieves using ultragravity-enhanced premixing according to claim 2, characterized in that: The hydrothermal crystallization temperature in step (6) is 105℃ and the time is 12h, and the drying temperature is 100℃ and the time is 12h.

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