Preparation method of waste incineration fly ash-based geopolymer / zeolite composite material and application of the composite material in adsorbing carbon dioxide

Abstract

The present application relates to a kind of preparation method of waste incineration fly ash base geopolymer / zeolite composite material and its application of adsorbing carbon dioxide;Mix incineration fly ash with deionized water, filter under stirring at room temperature to obtain dechlorination incineration fly ash;Alkali excitation solution and fly ash are stirred and mixed to form uniform slurry, then continue to stir uniformly after adding foaming agent, obtain porous geopolymer slurry;Porous geopolymer slurry is added dropwise into dimethyl silicone oil, solidification forming, filter to obtain porous spherical geopolymer;The porous spherical geopolymer is directly transferred to hydrothermal reaction kettle and hydrothermal treated, filter and dry to obtain geopolymer / zeolite;Geopolymer / zeolite is added into tetraethylenepentamine anhydrous ethanol solution and dispersed, dry to obtain tetraethylenepentamine modified geopolymer / zeolite composite material.The application of geopolymer / zeolite composite material prepared from incineration fly ash in adsorption field is developed, which is used for capturing and utilizing carbon dioxide in flue gas.

Description

Technical Field

[0001] This invention belongs to the field of comprehensive utilization of hazardous waste resources, specifically involving a method for preparing geopolymer / zeolite composite materials from waste incineration fly ash and its application in adsorbing carbon dioxide. Background Technology

[0002] Municipal solid waste incineration fly ash belongs to the CaO-SiO2-Al2O3-Cl system and exhibits volcanic ash-like properties, making it a potential raw material for geopolymer preparation. However, current methods for preparing geopolymers from incineration fly ash mainly focus on heavy metal solidification and its use as building materials, resulting in low added value for the products.

[0003] Geopolymers have a three-dimensional porous structure, similar to zeolites (in terms of porosity and chemical properties), and can be used as adsorbent materials in related fields of carbon dioxide adsorption. However, although geopolymers have a similar structure to zeolites, their porosity is much lower, resulting in a significantly lower adsorption efficiency compared to zeolites.

[0004] Compared to adsorbents of other shapes, spherical geopolymers, as gas adsorbents, possess excellent mechanical strength and better wear resistance, allowing them to be packed into fixed beds for continuous processing. This not only solves the problems of difficult recovery and easy agglomeration but also reduces gas diffusion resistance, significantly improving processing efficiency and meeting the needs of a wider range of industrial applications. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing geopolymer / zeolite composite materials from waste incineration fly ash and its application in carbon dioxide adsorption. The method involves preparing in-situ hydrothermal composite materials based on incineration fly ash using a dispersion-suspension-solidification technology coupled with tetraethylenepentamine. Then, a tetraethylenepentamine-loaded geopolymer / zeolite composite material is prepared by mixing it with tetraethylenepentamine to achieve efficient carbon dioxide capture. This solves the problem of low adsorption capacity of geopolymers in carbon dioxide capture. Simultaneously, it develops the application of geopolymers prepared from incineration fly ash in the adsorption field. The prepared composite material has advantages such as good wear resistance, high adsorption capacity, and long adsorption / desorption cycle, and can be used for carbon dioxide capture in flue gas, realizing high-value-added utilization of geopolymers based on incineration fly ash.

[0006] A method for developing a polymer / zeolite composite material based on fly ash from waste incineration includes the following steps:

[0007] 1) Mix incineration fly ash with deionized water, stir and filter at room temperature to obtain dechlorinated incineration fly ash;

[0008] 2) The solid obtained in step 1) is mixed with the alkali activation solution and fly ash to form a uniform slurry. Then, a foaming agent is added and the mixture is stirred until homogeneous to obtain a porous geopolymer slurry.

[0009] 3) The porous geopolymer slurry obtained in step 2) is added dropwise to dimethyl silicone oil, cured and shaped, and filtered to obtain porous spherical geopolymer;

[0010] 4) The porous spherical geopolymer obtained in step 3) is directly transferred to a hydrothermal reactor for hydrothermal treatment, and after filtration and drying, geopolymer / zeolite is obtained;

[0011] 5) Disperse tetraethylenepentamine in anhydrous ethanol solution to obtain a mixed solution;

[0012] 6) Add the material obtained in step 4) to the mixed solution obtained in step 5), stir evenly, and dry to obtain a geopolymer / zeolite composite material loaded with tetraethylenepentamine.

[0013] The preferred liquid-to-solid ratio (L / kg) of the aqueous solution to the incineration fly ash in step 1) is (3-20):1, and the stirring time is 2h-12h.

[0014] In the preferred step 2), the mass ratio of dechlorinated incineration fly ash to fly ash is 10:(5-10), the solid-liquid ratio (kg / L) of the mixture of dechlorinated incineration fly ash and fly ash to the alkali activator is 1:(2-5), the molar ratio of SiO2 / Na2O in the alkali activator is 1.0-1.9, the foaming agent is H2O2 (concentration is 30%), and the amount of foaming agent added accounts for 1-10% of the mass of the mixture slurry.

[0015] The preferred step 3) involves adding the product dropwise to dimethyl silicone oil with a stirring speed of 200-1000 rpm and a curing temperature of 50-120°C, and the curing time is 5-30 min.

[0016] The preferred hydrothermal temperature in step 4) is 90-200℃, the hydrothermal time is 6h-12h, and the hydrothermal pressure is 0-2MPa;

[0017] The preferred mass ratio of tetraethylenepentamine to anhydrous ethanol solution in step 5) is 1:(5-20);

[0018] The preferred step 6) contains 10-50% of the mass of the geopolymer / zeolite.

[0019] The geopolymer / zeolite composite material prepared from the above-mentioned waste incineration fly ash is used for carbon dioxide adsorption.

[0020] The composite material prepared in this invention is applied to carbon dioxide adsorption in a multi-temperature window (adsorption temperature range of 25-70℃);

[0021] Geopolymer / zeolite composites prepared using incinerator fly ash are applied in the field of carbon dioxide adsorption. These materials exhibit advantages such as high carbon dioxide adsorption capacity, long adsorption / desorption cycle time, and wear resistance. The carbon dioxide adsorption capacity ranges from 2.32 to 4.29 mmol / g, and the compressive strength ranges from 1.20 to 3.37 MPa, remaining stable throughout 10 adsorption / desorption cycles.

[0022] As can be seen from the above technical solution, compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] (1) The geopolymer / zeolite composite material prepared by the present invention using waste incineration fly ash is an adsorbent material with high carbon dioxide adsorption capacity. At the same time, the composite material has high compressive strength, which is conducive to its recycling and storage after use. It effectively prepares waste such as incineration fly ash into adsorbent material for carbon dioxide capture, so as to realize the high added value utilization of incineration fly ash and achieve "turning waste into treasure and treating waste with waste".

[0024] (2) The geopolymer / zeolite composite material prepared by the present invention utilizes the dispersion-suspension-solidification coupled in-situ hydrothermal technology. The geopolymer / zeolite composite material prepared by this method has excellent properties such as high pelletizing efficiency, high crystal conversion rate and large tetraethylenepentamine loading. Moreover, the preparation process is simple to operate. Unlike conventional hydrothermal, in-situ hydrothermal utilizes the water in the geopolymer without the need for external media. Therefore, no waste is generated in this process, which has high economic and environmental benefits.

[0025] (3) The geopolymer / zeolite composite material prepared by the present invention has tetraethylenepentamine loaded onto the geopolymer / zeolite material, which enables it to have stable carbon dioxide adsorption performance under medium and high temperature conditions, and is suitable for a wider adsorption temperature window, which can better meet the needs of industrial processing. Attached Figure Description

[0026] Figure 1 The XRD pattern of the geopolymer / zeolite material prepared in Example 1 of this invention.

[0027] Figure 2 The carbon dioxide adsorption test diagram is shown for the geopolymer / zeolite composite material prepared in Example 1 of this invention.

[0028] Figure 3 The carbon dioxide adsorption test diagram is shown for the geopolymer / zeolite composite material prepared in Example 2 of this invention.

[0029] Figure 4 The carbon dioxide adsorption test diagram is shown for the geopolymer / zeolite composite material prepared in Example 3 of this invention.

[0030] Figure 5The carbon dioxide adsorption test diagram is shown for the geopolymer / zeolite composite material prepared in Example 4 of this invention.

[0031] Figure 6 The carbon dioxide adsorption test diagram is shown for the geopolymer / zeolite composite material prepared in Example 5 of this invention.

[0032] Figure 7 The carbon dioxide adsorption test diagram is shown for the geopolymer / zeolite composite material prepared in Example 6 of this invention. Detailed Implementation Plan

[0033] The present invention will be described in detail below with reference to the embodiments, but the present invention is not limited to the following embodiments.

[0034] Example 1

[0035] 1) The incineration fly ash involved in this invention is taken from the bag ash of the waste incineration power plant. 300g of incineration fly ash is mixed with 3000mL of aqueous solution and stirred for 2 hours, and then filtered to obtain dechlorinated incineration fly ash.

[0036] 2) Take 250g of dechlorinated incineration fly ash, 250g of fly ash and 1000mL of alkali activator (n(SiO2 / Na2O)=1.2) and mix them thoroughly. Then add 25mL of H2O2 and continue stirring until uniform to obtain porous geopolymer slurry.

[0037] 3) The porous geopolymer slurry was dropped into a dimethyl silicone oil dispersion at a stirring speed of 600 rpm and a temperature of 75 ℃. After solidification for 10 min, it was filtered out to obtain porous spherical geopolymer.

[0038] 4) Place the porous spherical geopolymer from step 3) into a hydrothermal reactor. The hydrothermal reaction temperature is 180℃, and the hydrothermal time is 12 hours. After the reaction is stopped, geopolymer / zeolite is obtained; (e.g.) Figure 1 (as shown);

[0039] 5) Add 150 mL of tetraethylenepentamine to 750 mL of anhydrous ethanol and mix to disperse the mixture;

[0040] 6) Add 500g of geopolymer / zeolite from step 4) to the mixed solution in step 5) and mix thoroughly. After drying, a geopolymer / zeolite composite material loaded with 30% tetraethylenepentamine is obtained.

[0041] 7) Use the material obtained in step 6) for carbon dioxide adsorption testing.

[0042] The material obtained in this embodiment has an adsorption capacity of 2.75 mmol / g for carbon dioxide at 25°C. The adsorption results after 10 cycles are as follows: Figure 2 As shown, its compressive strength is 1.69 MPa.

[0043] The material obtained in this embodiment has an adsorption capacity of 2.75 mmol / g for carbon dioxide at 25°C. The adsorption results after 10 cycles are as follows: Figure 2 As shown, its compressive strength is 1.69 MPa.

[0044] Example 2

[0045] 1) The incineration fly ash involved in this invention is taken from the bag ash of the waste incineration power plant. 400g of incineration fly ash is mixed with 1200mL of aqueous solution and stirred for 6 hours, and then filtered to obtain dechlorinated incineration fly ash.

[0046] 2) Take 300g of dechlorinated incineration fly ash, 200g of fly ash and 2500mL of alkali activator (n(SiO2 / Na2O)=1.0) and mix them thoroughly. Then add 50mL of H2O2 and continue stirring until uniform to obtain porous geopolymer slurry.

[0047] 3) The porous geopolymer slurry was dropped into a dimethyl silicone oil dispersion at a stirring speed of 200 rpm and a temperature of 50 ℃. After solidification for 30 min, it was filtered out to obtain porous spherical geopolymer.

[0048] 4) Place the porous spherical geopolymer obtained in step 3) into a hydrothermal reactor. The hydrothermal reaction temperature is 180℃ and the hydrothermal time is 12h. After the reaction is stopped, the geopolymer / zeolite is obtained.

[0049] 5) Add 150 mL of tetraethylenepentamine to 3000 mL of anhydrous ethanol and mix to disperse the mixture;

[0050] 6) Add 500g of geopolymer / zeolite from step 4) to the mixed solution in step 5) and mix thoroughly. After drying, a geopolymer / zeolite composite material loaded with 30% tetraethylenepentamine is obtained.

[0051] 7) Use the material obtained in step 6) for carbon dioxide adsorption testing.

[0052] The material obtained in this embodiment had an adsorption capacity of 2.77 mmol / g for carbon dioxide at 25°C. The adsorption results after 10 cycles are as follows: Figure 3 As shown, its compressive strength is 1.20 MPa.

[0053] Example 3

[0054] 1) The incineration fly ash involved in this invention is taken from the bag ash of the waste incineration power plant. 300g of incineration fly ash is mixed with 3000mL of aqueous solution and stirred for 2 hours, and then filtered to obtain dechlorinated incineration fly ash.

[0055] 2) Take 250g of dechlorinated incineration fly ash, 125g of fly ash and 750mL of alkali activator (n(SiO2 / Na2O)=1.9) and mix them thoroughly. Then add 3.75mL of H2O2 and continue stirring until uniform to obtain porous geopolymer slurry.

[0056] 3) The porous geopolymer slurry was dropped into a dimethyl silicone oil dispersion at a stirring speed of 600 rpm and a temperature of 75 ℃. After solidification for 10 min, it was filtered out to obtain porous spherical geopolymer.

[0057] 4) The porous spherical geopolymer obtained in step 3) is placed in a hydrothermal reactor. The hydrothermal reaction temperature is 90℃, the hydrothermal time is 8h, and the reaction pressure is 2MPa. After the reaction is stopped, geopolymer / zeolite is obtained.

[0058] 5) Add 187.5 mL of tetraethylenepentamine to 1875 mL of anhydrous ethanol and mix to disperse the mixture;

[0059] 6) Add 375g of geopolymer / zeolite from step 4) to the mixed solution in step 5) and mix thoroughly. After drying, a geopolymer / zeolite composite material loaded with 50% tetraethylenepentamine is obtained.

[0060] 7) Use the material obtained in step 6) for carbon dioxide adsorption testing.

[0061] In this embodiment, the material obtained adsorbs 2.32 mmol / g of carbon dioxide at an adsorption temperature of 25°C. The adsorption results after 10 cycles are as follows: Figure 4 As shown, its compressive strength is 2.46 MPa.

[0062] Example 4

[0063] 1) The incineration fly ash involved in this invention is taken from the bag ash of the waste incineration power plant. 300g of incineration fly ash is mixed with 6000mL of aqueous solution and stirred for 12h, and then filtered to obtain dechlorinated incineration fly ash.

[0064] 2) Take 250g of dechlorinated incineration fly ash, 250g of fly ash and 1000mL of alkali activator (n(SiO2 / Na2O)=1.2) and mix them thoroughly. Then add 25mL of H2O2 and continue stirring until uniform to obtain porous geopolymer slurry.

[0065] 3) The porous geopolymer slurry was dropped into a dimethyl silicone oil dispersion at a stirring speed of 1000 rpm and a temperature of 120℃. After solidification for 5 minutes, it was filtered out to obtain porous spherical geopolymer.

[0066] 4) The porous spherical geopolymer from 3) is placed in a hydrothermal reactor. The hydrothermal reaction temperature is 200℃, the hydrothermal time is 6h, and the reaction pressure is 1MPa. After the reaction is stopped, geopolymer / zeolite is obtained.

[0067] 5) Add 150 mL of tetraethylenepentamine to 1500 mL of anhydrous ethanol and mix to disperse the mixture;

[0068] 6) Add 500g of geopolymer / zeolite from step 4) to the mixed solution in step 5) and mix thoroughly. After drying, a geopolymer / zeolite composite material loaded with 30% tetraethylenepentamine is obtained.

[0069] 7) Use the material obtained in step 6) for carbon dioxide adsorption testing.

[0070] In this embodiment, the adsorption temperature of the material was 25℃, the adsorption capacity of carbon dioxide was 3.43 mmol / g, and the adsorption results after 10 cycles were as follows. Figure 5 As shown, its compressive strength is 3.37 MPa.

[0071] Example 5

[0072] 1) The incineration fly ash involved in this invention is taken from the bag ash of the waste incineration power plant. 300g of incineration fly ash is mixed with 3000mL of aqueous solution and stirred for 2 hours, and then filtered to obtain dechlorinated incineration fly ash.

[0073] 2) Take 250g of dechlorinated incineration fly ash, 250g of fly ash and 1000mL of alkali activator (n(SiO2 / Na2O)=1.2) and mix them thoroughly. Then add 25mL of H2O2 and continue stirring until uniform to obtain porous geopolymer slurry.

[0074] 3) The porous geopolymer slurry was dropped into a dimethyl silicone oil dispersion at a stirring speed of 600 rpm and a temperature of 75 ℃. After solidification for 10 min, it was filtered out to obtain porous spherical geopolymer.

[0075] 4) Place the porous spherical geopolymer obtained in step 3) into a hydrothermal reactor. The hydrothermal reaction temperature is 180℃ and the hydrothermal time is 12h. After the reaction is stopped, the geopolymer / zeolite is obtained.

[0076] 5) Add 50 mL of tetraethylenepentamine to 500 mL of anhydrous ethanol and mix to disperse the mixture;

[0077] 6) Add 500g of geopolymer / zeolite from step 4) to the mixed solution in step 5) and mix thoroughly. After drying, a geopolymer / zeolite composite material loaded with 10% tetraethylenepentamine is obtained.

[0078] 7) Use the material obtained in step 6) for carbon dioxide adsorption testing.

[0079] In this embodiment, the adsorption temperature of the material was 25℃, the adsorption capacity of carbon dioxide was 2.60 mmol / g, and the adsorption results after 10 cycles were as follows. Figure 6 As shown, its compressive strength is 1.69 MPa.

[0080] Example 6

[0081] 1) The incineration fly ash involved in this invention is taken from the bag ash of the waste incineration power plant. 300g of incineration fly ash is mixed with 3000mL of aqueous solution and stirred for 2 hours, and then filtered to obtain dechlorinated incineration fly ash.

[0082] 2) Take 250g of dechlorinated incineration fly ash, 250g of fly ash and 1000mL of alkali activator (n(SiO2 / Na2O)=1.2) and mix them thoroughly. Then add 25mL of H2O2 and continue stirring until uniform to obtain porous geopolymer slurry.

[0083] 3) The porous geopolymer slurry was dropped into a dimethyl silicone oil dispersion at a stirring speed of 600 rpm and a temperature of 75 ℃. After solidification for 10 min, it was filtered out to obtain porous spherical geopolymer.

[0084] 4) Place the porous spherical geopolymer from step 3) into a hydrothermal reactor. The hydrothermal reaction temperature is 180℃ and the hydrothermal time is 12h. After the reaction stops, the geopolymer / zeolite is obtained.

[0085] 5) Add 150 mL of tetraethylenepentamine to 1500 mL of anhydrous ethanol and mix to disperse the mixture;

[0086] 6) Add 500g of geopolymer / zeolite from step 4) to the mixed solution in step 5) and mix thoroughly. After drying, a geopolymer / zeolite composite material loaded with 30% tetraethylenepentamine is obtained.

[0087] 7) Use the material obtained in step 6) for carbon dioxide adsorption testing.

[0088] In this embodiment, the adsorption temperature of the material was 70℃, the adsorption capacity of carbon dioxide was 4.29 mmol / g, and the adsorption results after 10 cycles were as follows. Figure 7 As shown, its compressive strength is 1.69 MPa.

[0089] Test case

[0090] The carbon dioxide adsorption performance of the incineration fly ash-based polymer / zeolite composite material prepared by the method described in the above embodiments was tested. The test method included the following steps:

[0091] 5g of incinerated fly ash-based polymer / zeolite composite material supported by quartz wool was placed in the isothermal heating zone of the fixed-bed reactor. Desorption treatment was first performed (100mL / min N2, 110℃-150℃ for 30min), followed by natural cooling to the adsorption temperature (25℃-70℃). A mixed gas (100mL / min, 15% carbon dioxide / 85% N2) was introduced for carbon dioxide adsorption testing. The test results were continuously monitored for 60min by a flue gas analyzer. The test results are shown in Table 1.

[0092]

[0093]

[0094] The geopolymer / zeolite composite material prepared by this method has excellent carbon dioxide adsorption performance, with a maximum adsorption capacity of 4.29 mmol / g and a maximum compressive strength of 3.37 MPa. Furthermore, it can be seen from Examples 1 and 6 that the geopolymer / zeolite composite material prepared by this invention has a wide carbon dioxide adsorption temperature window and good stability.

[0095] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements to the technical solutions of the present invention made by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a polymer / zeolite composite material based on waste incineration fly ash, characterized in that, Includes the following steps: 1) Mix incineration fly ash with deionized water, stir and filter at room temperature to obtain dechlorinated incineration fly ash; 2) Mix the solid obtained in step 1) with fly ash and alkali activator to form a uniform slurry, then add foaming agent and continue mixing to obtain a porous geopolymer slurry; The mass ratio of the dechlorinated incineration fly ash to the fly ash is 10:(5-10); 3) The porous geopolymer slurry obtained in step 2) is added dropwise to dimethyl silicone oil, cured and shaped, and filtered to obtain porous spherical geopolymer; Add it dropwise to dimethyl silicone oil with a stirring speed of 200-1000 rpm and a curing temperature of 50-120 ℃, and the curing time is 5-30 min; 4) The porous spherical geopolymer obtained in step 3) is directly transferred to a hydrothermal reactor for hydrothermal treatment to obtain geopolymer / zeolite; 5) Disperse tetraethylenepentamine in anhydrous ethanol solution to obtain a mixed solution; 6) Add the material obtained in step 4) to the mixed solution obtained in step 5), stir evenly, and dry to obtain a geopolymer / zeolite composite material loaded with tetraethylenepentamine. The content of the tetraethylenepentamine is 10-50% of the mass of the geopolymer / zeolite composite material.

2. The preparation method of the waste incineration fly ash-based polymer / zeolite composite material as described in claim 1, characterized in that, In step 2), the solid-liquid ratio of the mixture of dechlorinated incineration fly ash and fly ash to the alkali activator is 1 kg:(2-5) L. The molar ratio of SiO2 / Na2O in the alkali activator is 1.0-1.

9. The foaming agent is H2O2 with a concentration of 30%. The amount of foaming agent added accounts for 1-10% of the mass of the mixture slurry.

3. The preparation method of the waste incineration fly ash-based polymer / zeolite composite material as described in claim 1, characterized in that, Step 5) The mass ratio of tetraethylenepentamine to anhydrous ethanol solution is 1:(5-20).

4. The application of the geopolymer / zeolite composite material prepared by the method of claim 1 in carbon dioxide adsorption.

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