Method for preparing porous SOD (superoxide dismutase) zeolite molecular sieve by taking solid waste coal gangue as raw material

Abstract

The invention provides a method for preparing a porous SOD (superoxide dismutase) zeolite molecular sieve by taking solid waste coal gangue as a raw material. The method comprises the following steps: firstly, performing high-temperature alkali activation on coal gangue, then mixing with a proper amount of water, and fully and uniformly stirring to obtain a solution A; secondly, dissolving an aluminum source in a proper amount of water to obtain a solution B; then, slowly dropwise adding the solution B into the solution A in a stirring state, and uniformly mixing to obtain a synthetic solution; and finally, putting the synthetic liquid into a reaction kettle, and crystallizing under a certain condition to obtain the porous SOD zeolite molecular sieve. The hierarchical pore SOD molecular sieve synthesized by using the solid waste coal gangue as the raw material has the characteristics of high crystallinity and large specific surface area, does not need to use an organic template agent, and is simple in preparation process and easy for mass production. The hierarchical pore SOD zeolite molecular sieve has a good application prospect in the fields of catalysis and adsorption.

Description

Technical Field

[0001] The present invention belongs to High-value treatment of solid waste Technical field, especially Porous grade SOD zeolite molecular sieve Preparation method and application. Background Art

[0002] As a by-product solid waste of coal mining, coal gangue has attracted widespread attention in the field of solid waste utilization. In traditional solid waste treatment, coal gangue is mainly used for roadbed landfill or as building materials. However, the mineral components such as silicon and aluminum rich in coal gangue have not been efficiently utilized. At the same time, the silicon and aluminum sources in coal gangue are potential raw materials for synthesizing molecular sieves. If coal gangue is used to synthesize molecular sieves, it can not only reduce the preparation cost of molecular sieves, but also realize the high value and resource utilization of waste.

[0003] SOD type molecular sieves, with their unique pore structure and good adsorption properties, have shown extremely broad application prospects in many fields such as gas separation, catalysis, and ionic liquid adsorption. However, traditional synthesis methods often rely on high-purity chemical reagents, which makes the cost of material synthesis high. At the same time, this traditional synthesis method has a significant impact on the ecosystem and natural environment. Therefore, studying the preparation process of SOD type molecular sieves using low-cost coal gangue as raw material is expected to reduce the production cost of SOD type molecular sieves, which is of great significance for promoting the high-value utilization of solid waste and the application of SOD type molecular sieves in more fields. Summary of the invention

[0004] The purpose of the present invention is to provide a method for preparing a porous SOD type zeolite molecular sieve using solid waste coal gangue as a raw material, so as to solve the problems of high cost, environmental pollution and the like existing in the prior art.

[0005] To achieve the above object, the present invention adopts the following technical scheme: a method for preparing a porous grade SOD type zeolite molecular sieve using solid waste coal gangue as raw material, comprising the following steps:

[0006] 1. Pretreatment of coal gangue activation: crush and grind the coal gangue, and sieve it to obtain powder of a certain particle size; then alkali melt calcinate the powder at a certain temperature to remove impurities and organic matter to obtain activated coal gangue.

[0007] 2. Adjust the silicon-aluminum ratio: Add a certain amount of aluminum source to the water to adjust the silicon-aluminum ratio in the solution to meet the synthesis requirements of SOD molecular sieves. Stir and age for a period of time at a certain temperature to convert the silicon-aluminum substances in the solution into zeolite precursors.

[0008] 3. Crystallization: The zeolite precursor is transferred to a reactor and subjected to hydrothermal crystallization at a certain temperature for a period of time.

[0009] 4. Filtration, washing and drying: After the crystallization reaction is completed, the product is filtered and washed until the solution is neutral; then dried at a certain temperature to obtain a gangue-based porous grade SOD zeolite molecular sieve.

[0010] Compared with the prior art, the present invention has the following advantages:

[0011] 1. The present invention uses coal gangue as raw material, which reduces production costs, and has a simple preparation process, thereby realizing resource utilization of solid waste and reducing pollution to the environment.

[0012] 2. By simply adjusting the silicon-aluminum ratio, the structure and performance of SOD type molecular sieve can be effectively controlled to improve its application value.

[0013] 3. The synthesis method of the present invention has simple process, convenient operation and is easy to realize industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The present invention is a flow chart for preparing a porous grade SOD zeolite molecular sieve by using coal gangue as raw material.

[0015] Figure 2 This is the XRD diagram of the porous grade SOD zeolite molecular sieve synthesized using coal gangue as raw material in the present invention.

[0016] Figure 3 This is a SEM picture of the porous grade SOD zeolite molecular sieve synthesized using coal gangue as raw material in the present invention.

[0017] Figure 4 This is the BET diagram of the porous grade SOD zeolite molecular sieve synthesized using coal gangue as raw material in the present invention. Specific implementation plan

[0018] The present invention is further described in detail below in conjunction with specific implementation cases, but the implementation methods of the invention are not limited thereto. For process parameters not particularly noted, conventional techniques may be used.

[0019] Implementation Case 1 Mix 3g of sodium aluminate with 51g of water and stir evenly to obtain solution A, then add 15g of activated coal gangue powder to solution A and stir evenly to fully dissolve it to obtain solution B. Continue stirring at room temperature for 2 hours to obtain a light green sol solution. The mass ratio of the final synthetic liquid is CG:Al2O3:NaOH:H2O=10:3:12:51. The synthetic liquid is transferred to a stainless steel reactor with a polytetrafluoroethylene liner and crystallized at 80°C for 4 hours. After the reactor is cooled to room temperature, the sample after the crystallization reaction is obtained. The obtained sample is filtered and washed with deionized water until the filtrate is neutral, thereby obtaining a solid sample. Subsequently, the solid sample is placed in an oven and dried for 12 hours to finally obtain a light yellow powder, i.e., a porous grade SOD zeolite molecular sieve.

[0020] Implementation Case 2 Mix 3g of sodium aluminate with 51g of water and stir evenly to obtain solution A, then add 15g of activated coal gangue powder to solution A and stir evenly to fully dissolve it to obtain solution B. Continue stirring at room temperature for 2 hours to obtain a light green sol solution. The mass ratio of the final synthetic liquid is CG:Al2O3:NaOH:H2O=10:3:12:51. The synthetic liquid is transferred to a stainless steel reactor with a polytetrafluoroethylene liner and crystallized at a temperature of 100°C for 4 hours. After the reactor is cooled to room temperature, the sample after the crystallization reaction is obtained. The obtained sample is filtered and washed with deionized water until the filtrate is neutral, thereby obtaining a solid sample. Subsequently, the solid sample is placed in an oven and dried for 12 hours to finally obtain a light yellow powder, i.e., a porous grade SOD zeolite molecular sieve.

[0021] Implementation Case 3 Mix 3g of sodium aluminate with 51g of water and stir evenly to obtain solution A, then add 15g of activated coal gangue powder to solution A and stir evenly to fully dissolve it to obtain solution B. Continue stirring at room temperature for 2 hours to obtain a light green sol solution. The final synthetic liquid mass ratio is CG:Al2O3:NaOH:H2O=10:3:12:51. The synthetic liquid is transferred to a stainless steel reactor with a polytetrafluoroethylene liner and crystallized at a temperature of 120°C for 4 hours. After the reactor is cooled to room temperature, the sample after the crystallization reaction is obtained. The obtained sample is filtered and washed with deionized water until the filtrate is neutral, thereby obtaining a solid sample. Subsequently, the solid sample is placed in an oven and dried for 12 hours to finally obtain a light yellow powder, i.e., a porous grade SOD zeolite molecular sieve.

[0022] Implementation Case 4 Mix 3g of sodium aluminate with 51g of water and stir evenly to obtain solution A, then add 15g of activated coal gangue powder to solution A and stir evenly to fully dissolve it to obtain solution B. Continue stirring at room temperature for 2 hours to obtain a light green sol solution. The mass ratio of the final synthetic liquid is CG:Al2O3:NaOH:H2O=10:3:12:51. The synthetic liquid is transferred to a stainless steel reactor with a polytetrafluoroethylene liner and crystallized at a temperature of 100°C for 2 hours. After the reactor is cooled to room temperature, the sample after the crystallization reaction is obtained. The obtained sample is filtered and washed with deionized water until the filtrate is neutral, thereby obtaining a solid sample. Subsequently, the solid sample is placed in an oven and dried for 12 hours to finally obtain a light yellow powder, i.e., a porous grade SOD zeolite molecular sieve.

[0023] Implementation Case 5 Mix 3g of sodium aluminate with 51g of water and stir evenly to obtain solution A, then add 15g of activated coal gangue powder to solution A and stir evenly to fully dissolve it to obtain solution B. Continue stirring at room temperature for 2 hours to obtain a light green sol solution. The mass ratio of the final synthetic liquid is CG:Al2O3:NaOH:H2O=10:3:12:51. The synthetic liquid is transferred to a stainless steel reactor with a polytetrafluoroethylene liner and crystallized at a temperature of 100°C for 6 hours. After the reactor is cooled to room temperature, the sample after the crystallization reaction is obtained. The obtained sample is filtered and washed with deionized water until the filtrate is neutral, thereby obtaining a solid sample. Subsequently, the solid sample is placed in an oven and dried for 12 hours to finally obtain a light yellow powder, i.e., a porous grade SOD zeolite molecular sieve.

[0024] Implementation Case 6 Mix 3g of sodium aluminate with 51g of water and stir evenly to obtain solution A, then add 15g of activated coal gangue powder to solution A and stir evenly to fully dissolve it to obtain solution B. Continue stirring at room temperature for 2 hours to obtain a light green sol solution. The mass ratio of the final synthetic liquid is CG:Al2O3:NaOH:H2O=10:3:12:51. The synthetic liquid is transferred to a stainless steel reactor with a polytetrafluoroethylene liner and crystallized at a temperature of 100°C for 12 hours. After the reactor is cooled to room temperature, the sample after the crystallization reaction is obtained. The obtained sample is filtered and washed with deionized water until the filtrate is neutral, thereby obtaining a solid sample. Subsequently, the solid sample is placed in an oven and dried for 12 hours to finally obtain a light yellow powder, i.e., a porous grade SOD zeolite molecular sieve.

[0025] In the description of this specification, the description with reference to the terms "an implementation case", "some implementation cases", "examples", "specific examples" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the implementation case or example are included in at least one implementation case or example of the present invention. In this specification, the schematic representation of the above terms should not be understood as necessarily being directed to the same pair of implementation cases or examples. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more implementation cases or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different implementation cases or examples described in this specification.

Claims

1. A method for preparing porous SOD zeolite molecular sieve using solid waste coal gangue as raw material, characterized in that The solid waste coal gangue in the Liuhuanggou area of ​​Xinjiang is used as raw material, and then activated by high-temperature alkali melting and hydrothermal reaction is directly prepared in a one-step method; the synthesis process includes the following steps: (1) Coal gangue (CG) was crushed and sieved (sieve opening 80 mesh), and NaOH was added at a mass ratio of (CG:NaOH=1:1.2) and calcined at 800°C for 2 h. The activated coal gangue was cooled and ground and sieved to obtain alkaline activated coal gangue; (2) mixing an aluminum source and water and stirring to obtain a solution A; (3) slowly adding the alkaline activated coal gangue into solution A and stirring thoroughly to obtain solution B; (4) placing solution B in a hydrothermal reactor and obtaining a porous SOD molecular sieve through hydrothermal crystallization.

2. The method for synthesizing the porous SOD zeolite molecular sieve according to claim 1, characterized in that: In step (1), the coal gangue is sourced from the Suhuanggou area of ​​Xinjiang, and the mass of added NaOH is 120% of the mass of the raw material.

3. The method for synthesizing the porous SOD zeolite molecular sieve according to claim 1, characterized in that: In step (2), the aluminum source used was sodium aluminate and 51 mL of deionized water was added.

4. The method for synthesizing the porous SOD zeolite molecular sieve according to claim 1, characterized in that: In step (3), the stirring time is greater than 1 h.

5. The method for synthesizing the porous SOD zeolite molecular sieve according to claim 1, characterized in that: In step (4), the crystallization temperature is 50-100°C.

6. The method for synthesizing the porous SOD zeolite molecular sieve according to claim 1, characterized in that: The crystallization time of step (4) is 2 to 12 hours. A porous SOD zeolite molecular sieve is prepared by the synthesis method described in any one of claims 1 to 6.

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