A natural gas low-temperature combustion-supporting environmentally friendly additive and its preparation method

Abstract

The present application relates to the field of environmental protection additives, specifically disclosing a natural gas low-temperature combustion-supporting environmental protection additive and its preparation method. The natural gas low-temperature combustion-supporting environmental protection additive comprises the following substances in parts by weight: 10 to 50 parts of dimethyl carbonate, 0 to 10 parts of methyl tert-butyl ether, 10 to 20 parts of methanol, and 15 to 20 parts of dispersed catalytic particles; the dispersed catalytic particles are carbon aerogels adsorbed with nano-Pt particles. The natural gas low-temperature combustion-supporting environmental protection additive of the present application uses dimethyl carbonate, methyl tert-butyl ether, and methanol as liquid matrices, and a carbon aerogel material adsorbed with the precious metal Pt as a catalytic material. The environmental protection additive material is effectively coated and loaded in the boiling gas phase. A uniform bonding form is formed between the gas-phase environmental protection additive and the natural gas, so that the methane in the natural gas opens the gas-hydrogen-oxygen bond under the action of the environmental protection additive at 80 to 100°C, effectively catalyzing the combustion of natural gas in an oxygen-rich state, further improving the activity of natural gas in a low-temperature environment.

Description

Technical Field

[0001] The present application relates to the field of environmental protection additives, and more specifically, to a natural gas low-temperature combustion-supporting environmental protection additive and a preparation method thereof. Background Art

[0002] Natural gas refers to all gases found naturally in nature, including gases formed by various natural processes in the atmosphere, hydrosphere, and lithosphere (including oilfield gas, gasfield gas, mud volcano gas, coalbed methane, and biogenic gas). Natural gas is found in porous underground rock formations and includes oilfield gas, gasfield gas, coalbed methane, mud volcano gas, and biogenic gas, with smaller amounts also found in coal seams. It is a high-quality fuel and chemical feedstock. Natural gas is primarily used as a fuel and can be used to manufacture carbon black, chemicals, and liquefied petroleum gas. Propane and butane produced from natural gas are important raw materials for modern industry. Natural gas primarily consists of a mixture of gaseous low-molecular-weight hydrocarbons and non-hydrocarbon gases.

[0003] Because natural gas is primarily composed of methane, its sulfur and nitrogen contents are far lower than those of other petrochemical resources. Furthermore, due to its low carbon-to-hydrogen ratio and high calorific value, methane's utilization is less likely to cause secondary pollution. Therefore, compared to other primary energy sources, it is a cleaner energy source. However, methane is a very stable small organic molecule with a very low electron affinity and high ionization energy, making its activation very difficult.

[0004] Regarding the aforementioned related technologies, the inventors believe that due to thermodynamic reasons, the intermediate products formed after methane activation are prone to further reaction, producing thermodynamically more stable water and carbon dioxide. Therefore, catalytic activation of methane is difficult in low-temperature environments. This means that natural gas cannot be activated at low temperatures, resulting in inefficient combustion. Summary of the Invention

[0005] In order to improve the activity of natural gas in a low-temperature environment and enable it to burn fully, in the first aspect, the present application provides a natural gas low-temperature combustion-supporting and environmentally friendly additive, which includes the following substances in parts by weight: 10 to 50 parts of dimethyl carbonate, 0 to 10 parts of methyl tert-butyl ether, 10 to 20 parts of methanol and 15 to 20 parts of dispersed catalytic particles; the dispersed catalytic particles are carbon aerogels adsorbed with nano-Pt particles.

[0006] By adopting the above technical solution, since the present application uses dimethyl carbonate, methyl tert-butyl ether and methanol as liquid matrices, and since this type of liquid phase medium can form an azeotropic state at 60-100°C, at the same time, the carbon aerogel material adsorbed with the precious metal Pt used in the present application can effectively cover and load it in the boiling gas phase due to the low density of the carbon aerogel. By forming a uniform bonding form between the gas-phase environmental protection additive and the natural gas, the methane in the natural gas opens the gas-hydrogen-oxygen bond under the action of the environmental protection additive at 80-100°C, effectively catalyzing the combustion of natural gas in an oxygen-rich state, further improving the activity of natural gas in a low-temperature environment, and enabling the natural gas to be fully burned.

[0007] Furthermore, the natural gas low-temperature combustion-supporting environmentally friendly additive includes the following substances in parts by weight: 40 to 50 parts of dimethyl carbonate, 8 to 10 parts of methyl tert-butyl ether, 15 to 20 parts of methanol and 18 to 20 parts of dispersed catalytic particles; the dispersed catalytic particles are carbon aerogels adsorbed with nano-Pt particles.

[0008] By adopting the above technical solution, since this application optimizes the ratio of specific environmental protection additives, the natural gas environmental protection additives with this ratio optimize the synergistic effect between liquid phase media, so that the environmental protection additive materials can be azeotropic in a low-temperature environment, further improving the activity performance of natural gas in a low-temperature environment, so that the natural gas can be fully burned.

[0009] Furthermore, the surface of the carbon aerogel is also coated with a catalytic molecular sieve membrane prepared by crystallization using tetrapropylammonium hydroxide, sodium metaaluminate and ethyl orthosilicate as raw materials.

[0010] By adopting the above-mentioned technical solution, since the present application coats the molecular sieve membrane on the surface of the carbon aerogel for modification, the structural size of the coated molecular sieve membrane reduces the internal diffusion resistance and improves the binding performance between the environmental protection additive material and natural gas. At the same time, the pore structure inside the aerogel is coated and modified by the crystallized molecular sieve membrane layer to improve the structural performance of the carbon aerogel matrix. On this basis, due to the developed three-dimensional network structure and large porosity of the carbon aerogel, the external diffusion can be effectively reduced or even eliminated, the mass transfer rate of the environmental protection additive is accelerated, the catalytic performance of the environmental protection additive is improved, and the activity performance of natural gas in a low-temperature environment is further improved, so that the natural gas can be fully burned.

[0011] Furthermore, the dispersed catalytic particles have a particle size of 500 mesh.

[0012] By adopting the above technical solution, since the particle size of the catalytic particles is optimized in this application, there will be no problem of poor catalytic performance due to the particles being too small during actual use, nor will there be a problem of the catalytic particles being too large to be loaded in the gas phase for catalytic modification under an azeotropic system.

[0013] In a second aspect, the present application provides a method for preparing a low-temperature combustion-supporting environmentally friendly additive for natural gas, and the steps for preparing the low-temperature combustion-supporting environmentally friendly additive for natural gas include: S1, preparation of a carbon aerogel matrix: mixing resorcinol, sodium carbonate and deionized water, adding formaldehyde solution dropwise, aging and replacing the solvent, drying, heating and heat preservation calcination to obtain a carbon aerogel matrix, taking the carbon aerogel matrix and crushing and dispersing and modifying it to obtain dispersed modified matrix particles; S2, molecular sieve membrane coating modification: first taking deionized water, tetrapropylammonium hydroxide and sodium aluminate and stirring and mixing them, after the mixing is completed, adding tetraethyl orthosilicate to the dissolved solution, aging at room temperature to obtain an aged matrix liquid, Add the dispersed modified matrix particles to the aged matrix liquid, stir and mix, keep warm for crystallization, wash and dry to prepare the molecular sieve membrane coated modified matrix particles; S3, catalytic adsorption: take the molecular sieve membrane coated modified matrix particles and soak them in chloroplatinic acid, adsorb and dry them, heat and heat, calcinate them, let them stand and cool to room temperature, grind and disperse them through screening to obtain dispersed catalytic particles; S4, mixed preparation: weigh 40 to 50 parts of dimethyl carbonate, 8 to 10 parts of methyl tert-butyl ether, 15 to 20 parts of methanol and 18 to 20 parts of dispersed catalytic particles respectively, stir and mix them and ultrasonically disperse them to prepare a natural gas combustion-supporting environmentally friendly additive for low-temperature environments.

[0014] By adopting the above-mentioned technical solution, since this application optimizes the preparation steps of the environmentally friendly additive, through the layer-by-layer loading modification scheme, it can not only maximize the good catalytic performance of the environmentally friendly additive material, but also reduce the overall steps and costs of the environmentally friendly additive preparation, optimize the preparation scheme, and thus effectively improve the preparation efficiency of the natural gas combustion-supporting environmentally friendly additive.

[0015] Furthermore, the dispersion modification in step S1 is a process of crushing the carbon aerogel matrix with a silane coupling agent and then performing a coupling grafting dispersion modification process.

[0016] By adopting the above technical solution, since the present application adopts a coupling modification treatment scheme to disperse and modify the carbon aerogel matrix, a part of the polar groups can be combined with the active molecules on the surface of the carbon aerogel through chemical or physical effects, thereby improving its dispersion performance in the liquid phase. In this way, in the subsequent gas phase dispersion system, it can be evenly loaded and effectively catalyzed, thereby effectively improving the preparation efficiency of natural gas combustion-supporting environmentally friendly additives.

[0017] Furthermore, the crystallization temperature in step S2 is 150-155°C.

[0018] By adopting the above technical solution, since the present application optimizes the crystallization temperature of the molecular sieve membrane and improves the loading thickness of the molecular sieve membrane on the carbon aerogel surface, the catalytic particles can be effectively loaded in the dispersed gas phase without reducing the catalytic activity. In this way, in the subsequent catalytic activation process, the activity performance of natural gas in a low-temperature environment is further improved.

[0019] Furthermore, the heat preservation and roasting treatment temperature in step S3 is 450-500°C.

[0020] By adopting the above technical solution, since the present application optimizes the temperature for calcining and reducing chloroplatinic acid into dispersed platinum particles, during the effective catalytic reduction treatment, the decomposition of the carbon aerogel due to excessively high temperature is improved, and the defects of the carbon aerogel matrix are reduced, thereby further improving the activity performance of natural gas in a low-temperature environment.

[0021] In summary, this application includes at least one of the following beneficial technical effects:

[0022] First, this application uses dimethyl carbonate, methyl tert-butyl ether and methanol as liquid matrices, and carbon aerogel material adsorbed with precious metal Pt as catalytic material, effectively encapsulating and loading the environmental protection additive material in the boiling gas phase. By forming a uniform binding form between the gas-phase environmental protection additive and natural gas, the methane in the natural gas opens the gas-hydrogen-oxygen bond under the action of the environmental protection additive at 80-100°C, effectively catalyzing the combustion of natural gas in an oxygen-rich state, further improving the activity of natural gas in a low-temperature environment.

[0023] Second, the present application coats the carbon aerogel surface with a molecular sieve membrane for modification. The structural size of the coated molecular sieve membrane reduces the internal diffusion resistance and improves the binding performance between the environmentally friendly additive material and natural gas. The crystallized molecular sieve membrane layer coats and modifies the pore structure inside the aerogel, improves the structural properties of the carbon aerogel matrix, and further improves the activity performance of natural gas in a low-temperature environment, thereby enabling the natural gas to be fully burned.

[0024] Third, this application optimizes the preparation steps of the environmentally friendly additive. Through the layer-by-layer loading modification scheme, it can not only ensure the good catalytic performance of the environmentally friendly additive material to the greatest extent, but also reduce the overall steps and costs of the environmentally friendly additive preparation, optimize the preparation scheme, and thus effectively improve the preparation efficiency of the natural gas combustion-supporting environmentally friendly additive. DETAILED DESCRIPTION

[0025] The present application is further described in detail below with reference to the embodiments.

[0026] In the examples of this application, the instruments and equipment used are as follows, but not limited thereto:

[0027] Equipment: Glass rotor mass flowmeter reaction tube, thermocouple, dryer and gas chromatograph (Techcomp-GC7900) from Changzhou Advics Instrument Co., Ltd.

[0028] Example

[0029] Example 1

[0030] Resorcinol, sodium carbonate, and deionized water were mixed in a mass ratio of 1:3:10 and magnetically stirred at room temperature for 25 minutes to obtain a mixed solution, and a 5% formaldehyde solution by mass was added dropwise to the mixed solution in a volume ratio of 1:8. The mixture was stirred and placed in a 45°C oven for aging for 6 hours to obtain an aged sol solution; the aged sol solution was solvent-displaced with ethanol and then dried at 45°C for 6 hours to obtain a dried gel, which was taken and placed in a tubular atmosphere furnace, heated to 850°C at 5°C / min, kept warm for 45 minutes under an argon atmosphere, and allowed to cool to room temperature to obtain a carbon aerogel matrix;

[0031] The silane coupling agent and the carbon aerogel matrix were stirred and mixed in a mass ratio of 1:12 and ground at room temperature. The ground particles were collected and dried at 55° C. for 6 h. The dried ground particles were collected and crushed and ball-milled to a 500-mesh sieve to obtain dispersed modified matrix particles.

[0032] Weigh 1500 mL of deionized water, 60 g of tetrapropylammonium hydroxide, 0.5 g of sodium aluminate, and 150 mL of ethyl orthosilicate respectively. First, take the deionized water, tetrapropylammonium hydroxide, and sodium aluminate and stir and mix them. After the mixing is completed, collect the dissolved liquid and add ethyl orthosilicate dropwise to the dissolved liquid, stir and mix, and place it at room temperature for 6 hours to obtain an aged base liquid;

[0033] The dispersed modified matrix particles were added to the aged matrix liquid at a mass ratio of 1:5, stirred and mixed, and placed at 150°C for crystallization for 48 hours. After the crystallization was completed, they were rinsed with deionized water three times and then dried at 100°C for 6 hours to prepare coated modified matrix particles; the coated modified matrix particles were taken and added to 5% chloroplatinic acid at a mass ratio of 1:5, soaked for 3 hours, and then dried at room temperature for 6 hours. The adsorption modifier was taken and dried at 100°C to constant weight. The dried modified particles were collected and placed in a tubular atmosphere furnace, heated to 450°C and kept warm for 3 hours, allowed to cool to room temperature, ground and dispersed through a 500-mesh sieve to obtain dispersed catalytic particles; 400mL of dimethyl carbonate, 80mL of methyl tert-butyl ether, 150mL of methanol and 180g of dispersed catalytic particles were weighed separately to prepare a natural gas low-temperature combustion-supporting environmentally friendly additive.

[0034] Example 2

[0035] Resorcinol, sodium carbonate, and deionized water were mixed in a mass ratio of 1:3:10 and magnetically stirred at room temperature for 27 minutes to obtain a mixed solution, and a 5% formaldehyde solution by mass was added dropwise to the mixed solution in a volume ratio of 1:8. The mixture was stirred and placed in a 47°C oven for aging for 7 hours to obtain an aged sol solution. The aged sol solution was solvent-displaced with ethanol and then dried at 50°C for 7 hours to obtain a dried gel. The dried gel was placed in a tubular atmosphere furnace, heated to 875°C at 5°C / min, kept warm for 52 minutes under an argon atmosphere, and allowed to cool to room temperature to obtain a carbon aerogel matrix.

[0036] The silane coupling agent and the carbon aerogel matrix were stirred and mixed in a mass ratio of 1:12 and ground at room temperature. The ground particles were collected and dried at 57°C for 7 hours. The dried ground particles were collected and crushed and ball-milled to a 500-mesh sieve to obtain dispersed modified matrix particles.

[0037] Weigh 1550 mL of deionized water, 70 g of tetrapropylammonium hydroxide, 0.8 g of sodium aluminate, and 170 mL of ethyl orthosilicate respectively. First, take the deionized water, tetrapropylammonium hydroxide, and sodium aluminate and stir and mix them. After the mixing is completed, collect the dissolved liquid and add ethyl orthosilicate dropwise to the dissolved liquid, stir and mix, and place it at room temperature for 7 hours to obtain an aged base liquid;

[0038] The dispersed modified matrix particles were added to the aged matrix liquid at a mass ratio of 1:5, stirred and mixed, and placed at 152°C for crystallization for 49 hours. After the crystallization was completed, they were rinsed with deionized water 4 times and then dried at 105°C for 7 hours to prepare coated modified matrix particles; the coated modified matrix particles were taken and added to 5% chloroplatinic acid at a mass ratio of 1:5, soaked for 4 hours, and dried at room temperature for 7 hours. The adsorption modifier was taken and placed at 105°C for drying to constant weight. The dried modified particles were collected and placed in a tubular atmosphere furnace, heated to 475°C and kept warm for 4 hours, allowed to cool to room temperature, and ground and dispersed through a 500-mesh sieve to obtain dispersed catalytic particles; 450mL of dimethyl carbonate, 90mL of methyl tert-butyl ether, 170mL of methanol and 190g of dispersed catalytic particles were weighed separately to prepare a natural gas low-temperature combustion-supporting environmentally friendly additive.

[0039] Example 3

[0040] Resorcinol, sodium carbonate, and deionized water were mixed in a mass ratio of 1:3:10 and magnetically stirred at room temperature for 30 minutes to obtain a mixed solution, and a 5% formaldehyde solution by mass was added dropwise to the mixed solution in a volume ratio of 1:8. The mixture was stirred and placed in a 50°C oven for aging for 8 hours to obtain an aged sol solution; the aged sol solution was solvent-displaced with ethanol and then dried at 55°C for 8 hours to obtain a dried gel, which was taken and placed in a tubular atmosphere furnace, heated to 900°C at 5°C / min, kept warm for 60 minutes under an argon atmosphere, and allowed to cool to room temperature to obtain a carbon aerogel matrix;

[0041] The silane coupling agent and the carbon aerogel matrix were stirred and mixed in a mass ratio of 1:12 and ground at room temperature. The ground particles were collected and dried at 60° C. for 8 h. The dried ground particles were collected and crushed and ball-milled to a 500-mesh sieve to obtain dispersed modified matrix particles.

[0042] Weigh 1600 mL of deionized water, 80 g of tetrapropylammonium hydroxide, 1 g of sodium aluminate, and 200 mL of tetraethyl orthosilicate respectively. First, take the deionized water, tetrapropylammonium hydroxide, and sodium aluminate and stir and mix them. After the mixing is completed, collect the dissolved liquid and add the tetraethyl orthosilicate dropwise to the dissolved liquid. Stir and mix and place at room temperature for 8 hours to obtain an aged base liquid.

[0043] The dispersed modified matrix particles were added to the aged matrix liquid at a mass ratio of 1:5, stirred and mixed, and placed at 155°C for crystallization for 50 hours. After the crystallization was completed, they were rinsed with deionized water 5 times and then dried at 110°C for 8 hours to prepare coated modified matrix particles. The coated modified matrix particles were taken and added to 5% chloroplatinic acid at a mass ratio of 1:5. After soaking for 5 hours, they were dried at room temperature for 8 hours. The adsorption modifier was taken and placed at 110°C to dry to constant weight. The dried modified particles were collected and placed in a tubular atmosphere furnace, heated to 500°C and calcined for 5 hours. The particles were allowed to stand and cool to room temperature, and then ground and dispersed through a 500-mesh sieve to obtain dispersed catalytic particles. 500mL of dimethyl carbonate, 100mL of methyl tert-butyl ether, 200mL of methanol and 200g of dispersed catalytic particles were weighed separately to prepare a natural gas low-temperature combustion-supporting environmentally friendly additive.

[0044] Examples 4 to 6

[0045] The components of the low-temperature combustion-supporting environmentally friendly additive for natural gas in Examples 4 to 6 were changed, and the specific changes were shown in Table 1 below. Other conditions and component ratios were the same as in Example 1.

[0046] Table 1 Group distribution ratio

[0047]

[0048] Performance Testing The performance tests were conducted on Examples 1 to 6 respectively, and the natural gas low-temperature combustion-supporting environmentally friendly additives prepared in Examples 1 to 6 were tested.

[0049] Detection method / test method

[0050] (1) Test the low-temperature methane combustion characteristics of environmentally friendly additives:

[0051] The raw material atmosphere consisted of 3% CH₄, 0-0.01% SO₂, and the remainder air. The reaction space velocity was 8000 mL / (g·h), and the gas flow was controlled by a glass rotor mass flowmeter from Changzhou Ideks Instruments Co., Ltd. The reaction tube was 1200 mm long, and the isothermal zone of the heating furnace was approximately 200 mm long. The environmental additive particles in the reaction tube had a diameter of 2-4 mm and were loaded at a rate of 1.5 g. The reaction temperature was 350-700°C, with thermocouples collecting data and a control system controlling the heating temperature. Sulfur poisoning stability testing was conducted at 650°C for 10 hours. The reaction exhaust gas passed through a dryer (filled with alumina particles) and was analyzed by a gas chromatograph (Techcomp-GC7900). The activity of the environmental additive was evaluated by CH₄ conversion, characteristic reaction temperature, and activation energy.

[0052] The specific test results are shown in Table 2 below:

[0053] Table 2 Performance test table

[0054]

[0055]

[0056] Referring to the performance test comparison in Table 2, we can find that:

[0057] The performance of Examples 1 to 3 is compared. The reaction activation energy in Example 3 is the lowest. At the same time, compared with Examples 1 and 2, Example 3 has the highest addition ratio, which shows that the technical solution of the present application is feasible.

[0058] The performance of Examples 1 to 3 and Examples 4 to 6 is compared. Since Examples 4 to 6 use a different formula from Examples 1 to 3 and their reaction activation energy is increased, this shows that the present application optimizes the ratio of specific environmental protection additives, so that the environmental protection additive materials can co-exist in a low-temperature environment, further improving the activity performance of natural gas in a low-temperature environment, thereby enabling the natural gas to be fully burned.

[0059] Comparative Example

[0060] Comparative Examples 1 to 3

[0061] In Comparative Examples 1 to 3, carbon aerogels of equal mass were used to replace the dispersed catalytic particles used in the present application, and the remaining conditions and component ratios were the same as those in Examples 1 to 3.

[0062] Comparative Examples 4 to 6

[0063] Comparative Examples 4 to 6 use molecular sieve-coated carbon aerogel (which does not adsorb chloroplatinic acid) of equal mass to replace the dispersed catalytic particles used in this application, and the remaining conditions and component ratios are the same as those in Examples 1 to 3.

[0064] Comparative Examples 7 to 9

[0065] In Comparative Examples 7 to 9, 200-mesh dispersed catalytic particles of equal mass were used to replace the dispersed catalytic particles used in the present application, and the remaining conditions and component ratios were the same as those in Examples 1 to 3.

[0066] Performance testing

[0067] The natural gas low-temperature combustion-supporting environmentally friendly additives prepared in Comparative Examples 1 to 9 were tested respectively.

[0068] Detection method / test method

[0069] (1) Test the low-temperature methane combustion characteristics of environmentally friendly additives:

[0070] The raw material atmosphere consisted of 3% CH₄, 0-0.01% SO₂, and the remainder air. The reaction space velocity was 8000 mL / (g·h), and the gas flow was controlled by a glass rotor mass flowmeter from Changzhou Ideks Instruments Co., Ltd. The reaction tube was 1200 mm long, and the isothermal zone of the heating furnace was approximately 200 mm long. The environmental additive particles in the reaction tube had a diameter of 2-4 mm and were loaded at a rate of 1.5 g. The reaction temperature was 350-700°C, with thermocouples collecting data and a control system controlling the heating temperature. Sulfur poisoning stability testing was conducted at 650°C for 10 hours. The reaction exhaust gas passed through a dryer (filled with alumina particles) and was analyzed by a gas chromatograph (Techcomp-GC7900). The activity of the environmental additive was evaluated by CH₄ conversion, characteristic reaction temperature, and activation energy.

[0071] The specific test results are shown in Table 3 below:

[0072] Table 3 Performance test table

[0073]

[0074] Referring to the performance comparison in Table 3, we can find that:

[0075] Comparing Comparative Examples 1 to 3 of the present application with Examples 1 to 3, the catalytic activity of Comparative Examples 1 to 3, which uses carbon aerogels of equal mass instead of the dispersed catalytic particles used in the present application, is significantly reduced, indicating that the carbon aerogel material adsorbed with the precious metal Pt can effectively encapsulate and load the boiling gas phase, and form a uniform bonding form between the gas-phase environmental protection additive and the natural gas, thereby opening the hydrogen-oxygen bond of the natural gas, thereby effectively catalyzing the combustion of natural gas in an oxygen-rich state, further improving the activity of natural gas in a low-temperature environment, and enabling the natural gas to be fully burned.

[0076] Comparing Comparative Examples 4 to 6 of the present application with Examples 1 to 3, Comparative Examples 4 to 6 use an equal mass of molecular sieve-coated carbon aerogel (which does not adsorb chloroplatinic acid) instead of the dispersed catalytic particles used in the present application, but their activation performance still decreases. This shows that the platinum particle loading scheme used in the present application can improve the activity performance of natural gas in a low-temperature environment, thereby enabling the natural gas to be fully burned.

[0077] Comparing Comparative Examples 7 to 9 of the present application with Examples 1 to 3, Comparative Examples 7 to 9 use 200-mesh dispersed catalytic particles of equal mass instead of the dispersed catalytic particles used in the present application, but their activation performance still decreases. This shows that the present application optimizes the particle size of the catalytic particles so that in actual use, there will be no problem of poor catalytic performance due to the particles being too small, nor will there be a problem of the catalytic particles being too large to be loaded in the gas phase for catalytic modification under an azeotropic system.

[0078] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A natural gas low-temperature combustion-supporting environmentally friendly additive, characterized in that: The natural gas low-temperature combustion-supporting environmentally friendly additive is composed of the following substances in parts by weight: 40-50 parts of dimethyl carbonate; 8-10 parts of methyl tert-butyl ether; 15-20 parts of methanol; 18 to 20 parts of dispersed catalytic particles; the dispersed catalytic particles are carbon aerogels adsorbed with nano-Pt particles; the surface of the carbon aerogel is also coated with a catalytic molecular sieve membrane prepared by crystallization using tetrapropylammonium hydroxide, sodium metaaluminate and ethyl orthosilicate as raw materials.

2. The low-temperature combustion-supporting environmentally friendly natural gas additive according to claim 1, characterized in that: The particle size of the dispersed catalytic particles is 500 meshes.

3. A method for preparing a natural gas low-temperature combustion-supporting environmentally friendly additive, characterized in that: The preparation steps of the natural gas low-temperature combustion-supporting environmentally friendly additive are as follows: S1. Preparation of carbon aerogel matrix: resorcinol, sodium carbonate and deionized water are mixed, formaldehyde solution is added dropwise, and the mixture is aged and solvent replaced. After drying, the mixture is heated and calcined at a high temperature to obtain a carbon aerogel matrix. The carbon aerogel matrix is crushed and dispersed to obtain dispersed modified matrix particles. S2. Molecular sieve membrane coating modification: Deionized water, tetrapropylammonium hydroxide, and sodium metaaluminate are first stirred and mixed. After the mixing is completed, ethyl orthosilicate is added dropwise to the dissolved solution, and aged at room temperature to obtain an aged matrix liquid. The dispersed modified matrix particles are added to the aged matrix liquid, stirred and mixed, and kept warm for crystallization. The particles are washed and dried to prepare molecular sieve membrane coated modified matrix particles. S3, catalytic adsorption: taking the molecular sieve membrane-coated modified matrix particles and soaking them in chloroplatinic acid, adsorbing and drying them, heating them at elevated temperatures, keeping them warm and calcining them, standing them to cool to room temperature, grinding, dispersing and sieving them to obtain dispersed catalytic particles; S4. Mixing preparation: Weigh 40-50 parts of dimethyl carbonate, 8-10 parts of methyl tert-butyl ether, 15-20 parts of methanol and 18-20 parts of dispersed catalytic particles respectively by weight, stir and mix, and ultrasonically disperse to prepare a natural gas combustion-supporting environmentally friendly additive for low-temperature environments.

4. The method for preparing a natural gas low-temperature combustion-supporting environmentally friendly additive according to claim 3, characterized in that: The dispersion modification in step S1 is to crush the carbon aerogel matrix with a silane coupling agent, and then perform coupling grafting dispersion modification.

5. The method for preparing a natural gas low-temperature combustion-supporting environmentally friendly additive according to claim 3, characterized in that: The crystallization temperature in step S2 is 150-155°C.

6. The method for preparing a natural gas low-temperature combustion-supporting environmentally friendly additive according to claim 3, characterized in that: The heat preservation and roasting treatment temperature in step S3 is 450-500°C.

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