Coal combustion catalyst, its preparation method and application

Abstract

The application discloses a coal combustion catalyst, a preparation method and application thereof, and belongs to the technical field of energy saving and environmental protection. The preparation method of the coal combustion catalyst provided by the application comprises the following steps: S1, dissolving a transition metal salt in an ethanol dispersion solution of titanium tetrachloride; S2, mixing and reacting the mixture obtained in the step S1 with a surfactant, and removing a solvent. The coal combustion catalyst prepared by the preparation method is a solid, is convenient to transport, has a small dosage and good catalytic performance. The application further provides the coal combustion catalyst prepared by the preparation method and the application of the corresponding coal combustion catalyst.

Description

Technical Field

[0001] This invention relates to the field of energy conservation and environmental protection technology, and in particular to a coal-fired catalyst, its preparation method, and its application. Background Technology

[0002] Coal combustion has several drawbacks, such as incomplete combustion producing harmful gases like carbon monoxide, prolonged combustion time, and reduced combustion efficiency. To accelerate combustion and improve efficiency, related technologies involve adding catalysts to the coal, using chemical catalysis to enhance combustion. For example:

[0003] One technology provides an aqueous dispersion comprising magnesium sulfate, nickel salt, rare earth elements, and emulsifiers as a coal-saving agent; another technology provides a coal-saving agent comprising solid and liquid components, wherein the solid component is a mixture of sodium chloride, ammonium persulfate, cerium nitrate, polyoxyethylene ether, potassium chlorate, and calcium chloride dispersed in alkaline ethanol and then re-dried; and the liquid component is an aqueous dispersion of sodium lignosulfonate, graphene, and hydroxypropyl methylcellulose.

[0004] As can be seen from the above list, in traditional coal-fired catalysts, metal salts exist in a free state in the liquid dispersion, and the effect of a single metal ion is limited, resulting in limited improvement in coal combustion efficiency. Moreover, the solid content of coal-fired catalysts is low, with water often accounting for more than 80% of the mass, which greatly increases transportation costs. Even if coal-fired catalysts contain both surfactants and metal ions, the surfactants cannot ensure contact between the metal ions and the coal surface when wetting the coal surface, making it difficult to volatilize the metal ions and enhance their catalytic effect on coal combustion. In addition, to maintain the uniform dispersion and dissolution of metal salts, acidic solutions are needed to adjust the pH to acidic to prevent the metal salt solution from hydrolyzing and precipitating.

[0005] In summary, the effectiveness of traditional coal-fired catalysts varies greatly. Many coal-saving agents not only have high dosage requirements but also limited coal-saving effects and poor stability. Therefore, further in-depth optimization research is needed on the formulation and preparation methods of coal-saving agents. Summary of the Invention

[0006] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, the present invention proposes a method for preparing a coal-fired catalyst, the resulting coal-fired catalyst being solid, convenient to transport, requiring a small amount, and exhibiting good catalytic performance.

[0007] The present invention also provides a coal-fired catalyst prepared by the above preparation method.

[0008] The present invention also provides applications of the above-mentioned coal-fired catalyst.

[0009] According to an embodiment of a first aspect of the present invention, a method for preparing a coal-fired catalyst is provided, the method comprising the following steps:

[0010] S1. Dissolve the transition metal salt in an ethanol dispersion of titanium tetrachloride;

[0011] S2. After reacting the mixture obtained in step S1 with the surfactant, remove the solvent.

[0012] The mechanism of the preparation method is as follows:

[0013] In an ethanol dispersion of titanium tetrachloride, titanium tetrachloride reacts with ethanol to produce pale yellow to bright yellow titanium ethoxide. Simultaneously, ethanol partially polymerizes to form ethers and trace amounts of water. This trace amount of water effectively controls the hydrolysis process of the titanium source, facilitating the formation of ultra-small titanium dioxide. After adding metal salts and surfactants, during the subsequent solvent removal process, the transition metal salts, under the action of the surfactants, can bind to the surface of the formed ultra-small titanium dioxide, forming a monolithic coal combustion catalyst. Through the slow hydrolysis process of trace amounts of water and the action of the surfactants, the particle size of the obtained coal combustion catalyst is effectively controlled at the nanoscale.

[0014] The preparation method according to embodiments of the present invention has at least the following beneficial effects:

[0015] The preparation method provided by this invention yields a powdered coal combustion catalyst. This catalyst uses ultra-small titanium dioxide as a support, on which transition metal salts (or their products) are attached. Furthermore, the catalyst is modified with a surfactant.

[0016] The ultra-small size at the nanoscale can effectively enter the microporous structure on the surface of coal, thereby improving the combustion efficiency of coal.

[0017] Nanoscale titanium dioxide supports can synergistically enhance the combustion of coal with transition metal salts (or their products). Furthermore, nanoscale titanium dioxide provides loading sites for transition metal salts (or their products), improving the latter's dispersion uniformity and exposing more catalytically active sites.

[0018] On the one hand, surfactants act as ligands to enhance the adhesion strength between transition metal salts (or their products) and the titanium dioxide support; on the other hand, they control the size of the resulting coal-fired catalyst; furthermore, they improve the dispersion performance of the coal-fired catalyst in water, thus requiring only slight stirring to disperse into a uniform dispersion without adjusting the pH of the solution, making it convenient to use; furthermore, surfactants also improve the wetting performance of coal, and the tight binding between surfactants, the support, and the transition metal salts promotes the overall penetration of the coal-fired catalyst into the pores of the coal powder surface, improving the combustion efficiency of coal, making heat combustion more concentrated, and achieving coal-saving effects.

[0019] Compared with traditional water-dispersed coal-fired catalysts, solid-state coal-fired catalysts significantly reduce transportation costs.

[0020] However, if the preparation method is different from the preparation method provided by this invention, even if the raw materials are the same, different preparation effects will be achieved. For example, if titanium dioxide is added and mixed with the transition metal salt and surfactant, the combination between titanium dioxide and other components will be significantly weakened, and the overall synergistic effect will be weakened.

[0021] According to some embodiments of the present invention, the method for preparing the dispersion includes mixing titanium tetrachloride (CAS: 7550-45-0) and ethanol. The ethanol is anhydrous ethanol (water content ≤1%, further preferably ≤0.5%).

[0022] According to some embodiments of the present invention, the mixing comprises slowly adding the titanium tetrachloride dropwise to the ethanol. This order of addition, and the dropwise addition method, effectively controls the reaction process, resulting in effective control of the titanium dioxide particle size in the obtained coal-fired catalyst.

[0023] According to some embodiments of the present invention, the mixing time is 5 to 10 minutes. For example, it can be approximately 8 minutes.

[0024] According to some embodiments of the present invention, the mixing is carried out under stirring conditions. This can improve the mass transfer rate. The stirring speed is not strictly limited and can be adjusted as needed in actual production.

[0025] According to some embodiments of the present invention, the endpoint of the mixing is the change in color of the resulting dispersion from colorless to bright yellow.

[0026] According to some embodiments of the present invention, in step S1, the volume ratio of titanium tetrachloride to ethanol in the dispersion is 1:1.2 to 7.5. For example, it can be about 1:1.5, 1:2, 1:2.3, 1:2.4, 1:2.5, 1:2.8, 1:3, 1:4 or about 1:5.

[0027] According to some embodiments of the present invention, in step S1, the transition metal salt includes at least two of the transition metal nitrates, sulfates, and acetates.

[0028] According to some embodiments of the present invention, in step S1, the transition metal salt is selected from nitrates of transition metals. Specifically, the transition metal salt includes at least two of manganese nitrate, cerium nitrate, nickel nitrate, copper nitrate, ferric nitrate, and calcium nitrate. For example, it can be three, four, or five types.

[0029] The nickel nitrate includes at least one of anhydrous nickel nitrate and nickel nitrate hexahydrate;

[0030] The copper nitrate includes at least one of anhydrous copper nitrate and copper nitrate trihydrate.

[0031] According to some embodiments of the present invention, in step S1, the transition metal salt includes manganese nitrate, cerium nitrate, nickel nitrate, and copper nitrate.

[0032] The mass ratio of manganese nitrate to cerium nitrate is 1:0.1 to 10. For example, it can be 1:0.3 to 0.4.

[0033] The mass ratio of manganese nitrate to nickel nitrate is 1:0.1 to 10. For example, it can be 1:0.5 to 1. More specifically, it can be about 1:0.7 or about 1:0.8.

[0034] The mass ratio of manganese nitrate to copper nitrate is 1:0.1 to 10. For example, it can be about 1:1, 1:1.2, 1:1.5 or about 1:1.8.

[0035] According to some embodiments of the present invention, in step S1, the transition metal salt includes manganese nitrate, cerium nitrate, copper nitrate, and ferric nitrate.

[0036] The mass ratio of manganese nitrate to cerium nitrate is 1:0.1 to 10. For example, it can be 1:0.3 to 0.4.

[0037] The mass ratio of manganese nitrate to copper nitrate is 1:0.1 to 10. For example, it can be 1:0.5 to 1. More specifically, it can be about 1:0.7 or about 1:0.8.

[0038] The mass ratio of manganese nitrate to ferric nitrate is 1:0.1 to 10. For example, it can be 1:0.5 to 1. More specifically, it can be about 1:0.6 or about 1:0.65.

[0039] According to some embodiments of the present invention, in step S1, the transition metal salt includes manganese nitrate, cerium nitrate, nickel nitrate, and calcium nitrate. Wherein,

[0040] The mass ratio of manganese nitrate to cerium nitrate is 1:0.1 to 10. For example, it can be 1:0.5 to 0.8. More specifically, it can be about 1:0.6, 1:0.65, or about 1:0.7.

[0041] The mass ratio of manganese nitrate to nickel nitrate is 1:0.1 to 10. For example, it can be 1:1 to 5. More specifically, it can be about 1:1.2, 1:1.25, or about 1:3.

[0042] The mass ratio of manganese nitrate to calcium nitrate is 1:0.1 to 10. For example, it can be 1:0.8 to 1.2. More specifically, it can be about 1:1.

[0043] According to some embodiments of the present invention, in step S1, the transition metal salt includes manganese nitrate, cerium nitrate, and nickel nitrate.

[0044] The mass ratio of manganese nitrate to cerium nitrate is 1:0.1 to 10. For example, it can be 1:0.5 to 1. More specifically, it can be about 1:0.7, 1:0.8 or about 1:0.9.

[0045] The mass ratio of manganese nitrate to nickel nitrate is 1:0.1 to 10. For example, it can be 1:1 to 1.5. More specifically, it can be about 1:1.1, 1:1.2, or about 1:1.3.

[0046] According to some embodiments of the present invention, the mass-to-volume ratio of a single transition metal salt to the dispersion is 1 g: 20 to 500 mL. Specifically, it can be 1 g: 50 to 400 mL. More specifically, it can be about 1 g: 60 mL, 1 g: 70 mL, 1 g: 75 mL, 1 g: 80 mL, 1 g: 85 mL, 1 g: 90 mL, 1 g: 95 mL, 1 g: 100 mL, 1 g: 110 mL, 1 g: 120 mL, 1 g: 130 mL, 1 g: 135 mL, 1 g: 140 mL, 1 g: 150 mL, 1 g: 160 mL, 1 g: 170 mL, 1 g: 200 mL, 1 g: 230 mL, 1 g: 240 mL, 1 g: 250 mL, 1 g: 260 mL, 1 g: 270 mL, or about 1 g: 300 mL.

[0047] According to some embodiments of the present invention, in step S1, the mass-to-volume ratio of the transition metal salt and the dispersion is 1g:15-250mL.

[0048] According to some embodiments of the present invention, in step S1, the mass-to-volume ratio of the transition metal salt to the dispersion is 1g:18-50mL. Specifically, it can be approximately 1g:19mL, 1g:20mL, 1g:21mL, 1g:22mL, 1g:25mL, 1g:28mL, 1g:29mL, 1g:30mL, 1g:40mL, 1g:44mL, 1g:45mL, or approximately 1g:46mL.

[0049] According to some embodiments of the present invention, in step S2, the surfactant includes at least one of polyvinylpyrrolidone, polyethylene glycol, and hexadecyltritetramethylammonium bromide.

[0050] According to some embodiments of the present invention, the mass-to-volume ratio of the surfactant and the dispersion is 1 g: 400-4000 mL.

[0051] According to some embodiments of the present invention, the mass-to-volume ratio of the surfactant to the dispersion is 1g:800-1600mL. Specifically, it can be approximately 1g:900mL, 1g:1000mL, 1g:1050mL, 1g:1100mL, 1g:1150mL, 1g:1450mL, 1g:1500mL, or approximately 1g:1550mL.

[0052] According to some embodiments of the present invention, in step S2, the temperature of the mixing reaction is 80–100°C. For example, it can be about 85°C, 90°C, or about 95°C.

[0053] According to some embodiments of the present invention, in step S2, the endpoint of the mixing reaction is the appearance of a white precipitate.

[0054] According to an embodiment of the second aspect of the present invention, a coal combustion catalyst prepared by the preparation method described above is provided, wherein the particle size of the coal combustion catalyst is between 2 and 10 nm.

[0055] Since the coal-fired catalyst adopts all the technical solutions of the preparation method of the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments.

[0056] According to some embodiments of the present invention, the coal-fired catalyst comprises:

[0057] The carrier is nano-titanium dioxide;

[0058] The catalytically active ingredient is prepared from transition metal salts and is loaded on the surface of the support.

[0059] A surfactant, wherein the surfactant is loaded on the surface of the carrier.

[0060] According to an embodiment of a third aspect of the present invention, an application of the aforementioned coal-fired catalyst in catalytic coal combustion is provided.

[0061] Since the application adopts all the technical solutions of the coal-fired catalysts in the above embodiments, it has at least all the beneficial effects brought about by the technical solutions in the above embodiments.

[0062] According to some embodiments of the present invention, the application includes mixing the coal-fired catalyst with water; and mixing the mixture including the coal-fired catalyst with coal.

[0063] According to some embodiments of the present invention, the mass ratio of the coal-fired catalyst to water is 1:4 to 19. For example, it can be about 1:8, 1:9, or about 1:10.

[0064] According to some embodiments of the present invention, the mass percentage of the coal-fired catalyst and water relative to the mass of the coal is 0.08 to 0.12%. Specifically, it can be about 0.1%. Because of this low mass percentage, the product after mixing and grinding can be directly combusted without a subsequent drying process.

[0065] According to some embodiments of the present invention, the mixing process of the mixture of the coal-fired catalyst and the coal includes grinding. The grinding parameters are not strictly limited, as long as a homogeneous mixture is obtained.

[0066] Unless otherwise specified, the term "about" in this invention actually means that the error is allowed to be within ±2%, for example, about 100 is actually 100 ± 2% × 100.

[0067] Unless otherwise specified, "between" in this invention includes the number itself, for example, "between 2 and 3" includes the endpoint values ​​2 and 3.

[0068] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0069] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0070] Figure 1 This is a visual diagram of the dispersion obtained in step S1 of Example 1 of the present invention.

[0071] Figure 2 This is a transmission electron microscope image of the coal-fired catalyst obtained in Comparative Example 2 of this invention.

[0072] Figure 3This is a diagram showing the aqueous dispersion of the coal-fired catalyst obtained in Example 1 of the present invention and the dispersion effect of water on the coal. Detailed Implementation

[0073] The following will describe the concept and technical effects of the present invention clearly and completely with reference to embodiments, so as to fully understand the purpose, features and effects of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention.

[0074] In the description of this invention, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0075] Example 1

[0076] This example demonstrates the preparation of a coal-fired catalyst, with the following specific steps:

[0077] S1. Add 20 mL of titanium tetrachloride dropwise to 60 mL of anhydrous ethanol and stir thoroughly for 5 min. The mixture changes from colorless to bright yellow, yielding a dispersion. The appearance of the obtained dispersion is shown in the figure below. Figure 1 As shown.

[0078] Add 0.8 g of manganese nitrate, 0.3 g of cerium nitrate, 0.5 g of nickel nitrate hexahydrate, and 1.2 g of copper nitrate trihydrate to the obtained dispersion, respectively.

[0079] S2. After the transition metal salt is dissolved, add 0.1g of polyvinylpyrrolidone to the mixture obtained in step S1, and then heat in an oil bath at 80°C until the reaction is complete and a white precipitate appears.

[0080] The solvent in the resulting mixture was evaporated to dryness, yielding white powder particles, which is the coal-fired catalyst.

[0081] Example 2

[0082] This example demonstrates the preparation of a coal-fired catalyst, with the following specific steps:

[0083] S1. Add 40 mL of titanium tetrachloride dropwise to 80 mL of anhydrous ethanol and stir thoroughly for 5 min. The mixture changes from colorless to bright yellow, and a dispersion is obtained.

[0084] Add 1.5 g of manganese nitrate, 0.5 g of cerium nitrate, 1.2 g of copper nitrate trihydrate, and 0.9 g of ferric nitrate to the obtained dispersion, respectively.

[0085] S2. After the transition metal salt dissolves, add 0.08g of polyethylene glycol to the mixture obtained in step S1, and then heat in an oil bath at 90°C until the reaction is complete and a white precipitate appears.

[0086] The solvent in the resulting mixture was evaporated to dryness, yielding white powder particles, which is the coal-fired catalyst.

[0087] Example 3

[0088] This example demonstrates the preparation of a coal-fired catalyst, with the following specific steps:

[0089] S1. Gradually add 50 mL of titanium tetrachloride to 120 mL of anhydrous ethanol and stir thoroughly for 10 min. The mixture changes from colorless to bright yellow, and a dispersion is obtained.

[0090] Add 2.0 g of manganese nitrate, 1.3 g of cerium nitrate, 2.5 g of nickel nitrate hexahydrate, and 2.0 g of calcium nitrate to the obtained dispersion, respectively.

[0091] S2. After the transition metal salt is dissolved, add 0.15g of hexadecyltritetramethylammonium bromide to the mixture obtained in step S1, and then heat in an oil bath at 100°C until the reaction is complete and a white precipitate appears.

[0092] The solvent in the resulting mixture was evaporated to dryness, yielding white powder particles, which is the coal-fired catalyst.

[0093] Example 4

[0094] This example demonstrates the preparation of a coal-fired catalyst, with the following specific steps:

[0095] S1. Add 50 mL of titanium tetrachloride dropwise to 150 mL of anhydrous ethanol and stir thoroughly for 10 min. The mixture changes from colorless to bright yellow, and a dispersion is obtained.

[0096] Add 3.5 g of manganese nitrate, 2.8 g of cerium nitrate, and 4.2 g of nickel nitrate hexahydrate to the obtained dispersion.

[0097] S2. After the transition metal salt is dissolved, add 0.2g of polyvinylpyrrolidone to the mixture obtained in step S1, and then heat in an oil bath at 100°C until the reaction is complete and a white precipitate appears.

[0098] The solvent in the resulting mixture was evaporated to dryness, yielding white powder particles, which is the coal-fired catalyst.

[0099] Comparative Example 1

[0100] This example prepares a coal-fired catalyst, which differs from Example 3 in that:

[0101] In step S1, no transition metal salts are added;

[0102] In step S2, no surfactant is added;

[0103] After step S2, the white precipitate obtained in step S2, an equal amount of transition metal salt from Example 3, and a surfactant are dry-mixed.

[0104] Comparative Example 2

[0105] This example prepares a coal-fired catalyst, which differs from Example 3 in that:

[0106] In step S1, no transition metal salts are added;

[0107] In step S2, no surfactant is added;

[0108] Comparative Example 3

[0109] This example prepares a coal-fired catalyst, which differs from Example 3 in that:

[0110] In step S1, titanium tetrachloride is not added.

[0111] Application examples

[0112] This example demonstrates the application of the coal-fired catalyst obtained in the embodiments or comparative examples in catalytic coal combustion. The specific steps are as follows:

[0113] D1. Mix and disperse the coal-fired catalyst and water;

[0114] D2. Mix the mixture obtained in step D1 with the coal, wherein the mixture obtained in step D1 accounts for 0.1% of the mass of the coal.

[0115] In the different embodiments, the amounts of coal-fired catalyst and water used are shown in Table 1. The control example does not add a coal-fired catalyst, but instead adds an equal amount of water as in step D2.

[0116] Table 1 shows the mass ratio of coal-fired catalyst and water in application examples.

[0117] serial number Coal-fired catalyst: water Example 1 5:95 Example 2 10:90 Example 3 20:80 Example 4 10:90 Comparative Example 1 20:80 Comparative Example 2 20:80 Comparative Example 3 20:80 Comparison Example /

[0118] Test case

[0119] The first aspect of this example tested the morphology of the coal-fired catalyst obtained in the previous embodiment. The specific testing method was TEM. The results showed that the coal-fired catalyst was distributed in particulate form, with a particle size between 2 and 10 nm, and the particle size was mainly dominated by the particle size of the titanium dioxide support. However, due to the small particle size, it was difficult to accurately characterize it using methods such as particle size analyzers; it could only be detected through electron microscopy. The specific electron microscopy image of the titanium dioxide support obtained in Comparative Example 2 is shown below. Figure 2 As shown.

[0120] The first aspect of this example tested the dispersibility of the coal-fired catalyst, water, and coal obtained in the examples and application examples. Specifically, the coal-fired catalyst from Example 1 was mixed with water at a mass ratio of 5:95 to obtain 20 mL of dispersion. Under the same conditions, 2 g of pulverized coal was added to either the dispersion or an equal volume of water, and the dispersion state of the pulverized coal was recorded after 20 seconds.

[0121] Test results show that the coal-fired catalyst obtained in Example 1 can completely disperse coal powder in water within 20 seconds, while it shows almost no dispersion in pure water. This indicates that the coal-fired catalyst prepared in Example 1 has a good effect on wetting the coal surface; and the dispersion performance of the coal-fired catalysts obtained in the examples is comparable. Specific test results are as follows... Figure 3 As shown in Table 1.

[0122] Table 1. Dispersion performance of coal-fired catalysts on pulverized coal obtained in the examples and comparative examples within 20 seconds.

[0123] serial number Comparison Example Comparative Example 1 Comparative Example 2 Comparative Example 3 Dispersion No dispersion Partially dispersed Partially dispersed Partially dispersed serial number Example 1 Example 2 Example 3 Example 4 Dispersion dispersion dispersion dispersion dispersion

[0124] The second aspect of this example tested the ignition temperature and burnout rate of the coal treated with the coal-fired catalyst in the application example. The ignition temperature was determined through thermogravimetric analysis, and the burnout rate was the ratio of the mass of coal consumed to the mass of coal fed in after holding at 850℃ for 30 minutes in a tubular furnace under air conditions. The test results are shown in Tables 2 and 3.

[0125] Table 2 Ignition point temperature of coal

[0126] serial number Comparison Example Comparative Example 1 Comparative Example 2 Comparative Example 3 Ignition point temperature / ℃ 453 438 446 441 serial number Example 1 Example 2 Example 3 Example 4 Ignition point temperature / ℃ 403 411 407 419

[0127] Table 3. Combustion rate of coal

[0128] serial number Comparison Example Comparative Example 1 Comparative Example 2 Comparative Example 3 Burn rate 80.3％ 83.3％ 81.8％ 82.6％ serial number Example 1 Example 2 Example 3 Example 4 Burn rate 86.7％ 86.2％ 85.1％ 85.4％

[0129] According to the results in Tables 2-3, compared with the comparative examples, the coal obtained by mixing the coal-fired catalyst obtained in the embodiments of the present invention has a lower ignition temperature of 20-50°C and a higher combustion rate of 3-7%. Therefore, the coal-fired catalyst provided by the present invention has good catalytic performance for coal combustion.

[0130] A comparison of the results from Examples 1 to 4 shows that the catalytic performance of the coal-fired catalyst varies slightly depending on the amount and type of raw materials used, but all exhibit excellent catalytic performance. Furthermore, it can be anticipated that further optimization within the scope provided by this invention may yield coal-fired catalysts with even better catalytic performance than those in Examples 1 to 4.

[0131] Comparing Example 3 and Comparative Example 1, it can be seen that even if the types and amounts of raw materials are the same, if titanium dioxide particles are directly mixed with transition metal salts and surfactants by wet method, the synergistic effect among the three cannot be fully exerted, and the catalytic performance of the resulting coal-fired catalyst decreases.

[0132] Comparing Example 3 with Comparative Examples 2-3, it can be seen that the catalytic performance of the coal-fired catalyst provided by the present invention is superior to the sum of the performances of titanium dioxide alone and transition metal salts alone, indicating a significant synergistic effect in the coal-fired catalyst provided by the present invention. Furthermore, in Comparative Example 3, the carrier effect of titanium dioxide is lacking, making it impossible to guarantee dispersibility.

[0133] In summary, the coal combustion promoter provided by this invention has a good effect on promoting coal combustion and can be applied in practical combustion applications to improve coal combustion efficiency and promote energy conservation and emission reduction.

[0134] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. The application of a coal-fired catalyst in catalytic coal combustion, characterized in that, The preparation method of the coal-fired catalyst includes the following steps: S1. Dissolve a transition metal salt in an ethanol dispersion of titanium tetrachloride; the transition metal salt includes at least two of manganese nitrate, cerium nitrate, nickel nitrate, copper nitrate, ferric nitrate, and calcium nitrate; S2. After reacting the mixture obtained in step S1 with the surfactant, the solvent is removed; the surfactant includes at least one of polyvinylpyrrolidone, polyethylene glycol and hexadecyltritetramethylammonium bromide.

2. The application according to claim 1, characterized in that, In step S1, the mass-to-volume ratio of the transition metal salt to the dispersion is 1g:15~250mL.

3. The application according to claim 1, characterized in that, In step S1, the volume ratio of titanium tetrachloride to ethanol in the dispersion is 1:1.2~7.

5.

4. The application according to claim 3, characterized in that, In step S1, the method for preparing the dispersion includes mixing the titanium tetrachloride and ethanol; and / or, the endpoint of the mixing is that the color of the resulting dispersion changes from colorless to bright yellow.

5. The application according to claim 1, characterized in that, In step S2, the mass-to-volume ratio of the surfactant to the dispersion is 1g:400~4000mL.

6. The application according to any one of claims 1 to 5, characterized in that, In step S2, the temperature of the mixing reaction is 80~100℃; and / or, the endpoint of the mixing reaction is the appearance of a white precipitate.

7. The application according to any one of claims 1 to 5, characterized in that, The particle size of the coal-fired catalyst is between 2 and 10 nm.

8. The application according to claim 1, characterized in that, The application includes mixing the coal-fired catalyst with water; and mixing the resulting mixture with coal.

9. The application according to claim 8, characterized in that, The mass ratio of the coal-fired catalyst to water is 1:4 to 19; and / or, the mass of the coal-fired catalyst and water as a percentage of the mass of the coal is 0.08 to 0.12%.

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