Catalyst as well as preparation method and application thereof
The catalyst prepared by the dual hydrolysis reaction of anions and cations solves the problems of easy sintering and deactivation of existing catalysts and the complexity of preparation. It achieves high selectivity and conversion rate of efficient carbon dioxide methanation reaction and is suitable for industrial production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-11
- Publication Date
- 2026-03-13
AI Technical Summary
Existing carbon dioxide methanation catalysts suffer from problems such as high raw material costs, weak metal-support interaction which easily leads to sintering deactivation, or complex preparation processes that are unsuitable for large-scale production.
A catalyst containing aluminate ions, active metal ions, support metal ions, and auxiliary metal ions was prepared by using a double hydrolysis reaction of anions and cations to form a precipitate, which was then separated from the solution system and calcined. By adjusting the molar ratio and calcination conditions, ultra-small active component nanoparticles were formed to enhance the interaction between the metal and support.
The prepared catalyst exhibits high methane selectivity and carbon dioxide conversion rate at low temperatures, and also possesses excellent resistance to sintering and carbon deposition, making it suitable for large-scale industrial applications.
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Abstract
Description
Technical Field
[0001] This invention relates to catalysts, and more particularly to a catalyst for the methanation of carbon dioxide. Background Technology
[0002] Carbon dioxide is the final product of the complete combustion of carbonaceous organisms. With the large-scale use of fossil fuels, the amount of carbon dioxide in the atmosphere is constantly increasing. To mitigate the environmental impact of carbon dioxide, carbon dioxide capture, utilization, and storage (CCUS) technology has received widespread attention. Converting CO2 into CH4 through catalytic methods can effectively reduce CO2 emissions, while the generated CH4 can be used as a clean energy source for subsequent resource utilization.
[0003] The methanation reaction of carbon dioxide is as follows:
[0004]
[0005] This reaction is strongly exothermic; low temperatures favor the forward reaction, while high temperatures reduce methane selectivity and easily cause sintering and deactivation of the catalyst's active components. To achieve high methane selectivity at ambient pressure, the reaction temperature is ideally below 400°C. However, the carbon dioxide methanation reaction involves an octet transfer process, exhibiting significant kinetic limitations. Therefore, developing a low-temperature, high-efficiency catalyst is crucial for realizing this reaction.
[0006] Existing methanation catalysts or raw materials are either expensive, have weak metal-support interactions, and are prone to sintering deactivation, making them unsuitable for large-scale production; or their preparation processes are complex, limiting their industrial application value. Summary of the Invention
[0007] To overcome at least one of the defects of the prior art, in a first aspect, one embodiment of the present invention provides a method for preparing a catalyst, comprising the following steps:
[0008] The anions and cations undergo a double hydrolysis reaction to form a precipitate; and
[0009] The precipitate was separated from the solution system and calcined to obtain the catalyst;
[0010] Wherein, the anion includes aluminate ions, and the cation includes active metal ions, carrier metal ions, and auxiliary metal ions; the active metal ions include nickel ions and / or cobalt ions, the carrier metal ions include aluminum ions, and the auxiliary metal ions include one or more of magnesium ions, calcium ions, cerium ions, and lanthanum ions.
[0011] Secondly, one embodiment of the present invention provides a catalyst prepared by the above-described preparation method.
[0012] Thirdly, one embodiment of the present invention provides the application of the above-described catalyst in a carbon dioxide methanation process.
[0013] The catalyst preparation method of one embodiment of the present invention can produce a catalyst with excellent performance. When the catalyst is used in the carbon dioxide methanation process, it can improve the conversion rate of carbon dioxide while maintaining high methane selectivity. Detailed Implementation
[0014] Typical embodiments embodying the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various variations in different embodiments without departing from the scope of the present invention, and the description herein is for illustrative purposes only and not intended to limit the present invention.
[0015] One embodiment of the present invention provides a method for preparing a catalyst, comprising the following steps:
[0016] The anions and cations undergo a double hydrolysis reaction to form a precipitate; and
[0017] The precipitate was separated from the solution system and calcined to obtain the catalyst;
[0018] Among them, anions include aluminate ions (AlO2 ions) - The cations include active metal ions, carrier metal ions, and auxiliary metal ions; the active metal ions include nickel ions and / or cobalt ions, the carrier metal ions include aluminum ions, and the auxiliary metal ions include one or more of magnesium ions, calcium ions, cerium ions, and lanthanum ions.
[0019] In one embodiment, multiple cations are reacted with AlO2. - When anions are placed in the same aqueous solution system, they will mutually promote the hydrolysis process and form hydroxide precipitates. The slow hydrolysis of ions and the formation of precipitates result in highly uniform dispersion of the generated active components and additives, which can form ultra-small active component nanoparticles and form strong metal-support interactions with the support. This can effectively inhibit the sintering of active component particles and the carbon deposition on the surface, giving the catalyst excellent anti-sintering and anti-carbon deposition properties.
[0020] In one embodiment, in order to ensure the rate of the double hydrolysis process, the molar ratio of the above-mentioned anions and cations participating in the hydrolysis reaction is (0.9-1.1):(0.9-1.1), and more specifically 1:1.
[0021] In one embodiment, taking nickel ions as an example, they react with AlO2 - The double hydrolysis reaction equations for ions are as follows:
[0022]
[0023] In one embodiment, the catalyst preparation method includes: mixing an aluminate solution with a soluble salt solution to react and obtain a precipitate; then, separating the precipitate from the solution system and subjecting it to drying and calcination; wherein the aluminate solution contains the aforementioned anions and the soluble salt solution contains the aforementioned cations.
[0024] In one embodiment, the raw materials for preparing the aluminate solution include sodium aluminate, and the raw materials for preparing the soluble salt solution include nitrates and / or hydrates of active metals, aluminum nitrates and / or hydrates of aluminum nitrates and / or hydrates of auxiliary metals.
[0025] In one embodiment, the nitrate and / or hydrate of the active metal includes one or more of Ni(NO3)2, Ni(NO3)2·6H2O, Co(NO3)2, and Co(NO3)2·6H2O.
[0026] In one embodiment, the nitrate and / or hydrate of the auxiliary metal includes one or more of Mg(NO3)2, Mg(NO3)2·6H2O, Ca(NO3)2, Ca(NO3)2·4H2O, Ce(NO3)3, Ce(NO3)3·6H2O, La(NO3)3, and La(NO3)3·6H2O.
[0027] In one embodiment, aluminum nitrate and / or its hydrates comprise Al(NO3)3 and / or Al(NO3)3·9H2O.
[0028] In one embodiment, the precipitate can be separated from the solution system by, for example, filtration, and then the separated solid precipitate can be dried; further, the drying temperature can be 100-120°C, for example 105°C, 110°C, or 115°C; and the drying time can be 10-20 hours, for example 12 hours, 14 hours, 15 hours, 16 hours, 17 hours, or 18 hours.
[0029] In one embodiment, the dried solid material can be roasted at a temperature of 400–600°C, such as 450°C, 500°C, or 550°C, for a duration of 1–5 hours, such as 2 hours, 3 hours, or 4 hours.
[0030] In one embodiment, the calcination process can be carried out in a muffle furnace, and the heating rate of the muffle furnace can be 3 to 5 °C / min, for example 3.5 °C / min, 4 °C / min, or 4.5 °C / min.
[0031] In one embodiment, the catalyst preparation method includes the following steps:
[0032] (1) Add aluminate to water (e.g., deionized water) to prepare a first solution;
[0033] (2) Add the nitrate of the active metal and / or its hydrate, the nitrate of the auxiliary metal and / or its hydrate, and the aluminum nitrate and / or its hydrate to water (e.g., deionized water) to prepare a second solution;
[0034] (3) Transfer the second solution into a funnel and slowly add it dropwise into the first solution, stirring constantly at room temperature until precipitation is complete;
[0035] (4) Filter the precipitate, wash it several times, and dry it at 100-120℃ for 10-20 hours;
[0036] (5) After drying, the obtained solid is calcined in a muffle furnace at 400-600℃ for 1-5 hours. The heating rate of the muffle furnace is 3-5℃ / min. After cooling, the catalyst is obtained.
[0037] One embodiment of the present invention provides a catalyst prepared by the above-described preparation method.
[0038] In one embodiment, the catalyst comprises 9 to 20 wt% of an active component, 65 to 85 wt% of a support, and 5 to 15 wt% of an auxiliary agent, wherein the percentages are based on the total weight of the catalyst.
[0039] In one embodiment, the content of the active component in the catalyst can be 9 to 20 wt%, more preferably 10 to 13 wt%, for example 9.5 wt%, 10.5 wt%, 11 wt%, 11.5 wt%, 12 wt%, and 12.5 wt%. Unless otherwise specified, the content of the active component in this document is based on the content of the active metal (nickel or cobalt).
[0040] In one embodiment, the content of the support in the catalyst can be 65-85 wt%, for example 68 wt%, 70 wt%, 73 wt%, 75 wt%, 77 wt%, 80 wt%, or 82 wt%.
[0041] In one embodiment, the content of the additive in the catalyst can be 5 to 15 wt%, for example 7 wt%, 7.5 wt%, 8 wt%, 10 wt%, 12 wt%, 13 wt%, or 14 wt%.
[0042] In one embodiment, the active component includes one or more of Ni and / or its oxides, Co and / or its oxides, the support is Al2O3, and the auxiliary agent includes one or more of MgO, CaO, CeO2, and La2O3.
[0043] In one embodiment, the acidity or alkalinity of the catalyst surface can be controlled by adjusting the content of catalyst promoters, thereby enhancing CO2 adsorption capacity and methane selectivity.
[0044] In one embodiment, the particle size of the catalyst active component is 1.5 to 3.5 nm, for example 1.7 nm, 1.8 nm, 2.0 nm, 2.1 nm, 2.5 nm, 2.8 nm, 3.0 nm, or 3.1 nm.
[0045] One embodiment of the present invention provides the application of the above-described catalyst in a carbon dioxide methanation process.
[0046] One embodiment of the present invention provides a method for preparing methane, comprising reacting carbon dioxide and hydrogen under the action of the above-mentioned catalyst to obtain methane.
[0047] The catalyst preparation method of one embodiment of the present invention has the advantages of simple process route, environmental friendliness, low raw material price and low energy consumption; and the catalyst prepared has excellent catalytic performance and anti-carbon deposition properties.
[0048] The catalyst preparation method of one embodiment of the present invention does not require the use of acidic or alkaline liquids, but only requires a precursor (such as nitrates) and water. The hydrolysis solution is nearly neutral, eliminating the need for pH adjustment and avoiding the generation of waste liquid and waste of water resources. In addition, the use of inorganic aluminum salts as precursors makes the preparation process green and environmentally friendly, suitable for large-scale industrial production.
[0049] Compared with catalysts prepared by traditional impregnation and precipitation methods, the catalyst of one embodiment of the present invention has smaller active component particle size, higher CO2 conversion rate and CO2 adsorption capacity, better catalytic performance for carbon dioxide methanation, and excellent anti-sintering and anti-carbon deposition properties.
[0050] The preparation and application of a catalyst according to one embodiment of the present invention will be further described below with reference to examples. The test methods involved in the examples and comparative examples are as follows.
[0051] Test methods
[0052] 1. Particle size of the active component of the catalyst
[0053] The particle size of the catalyst active components was obtained by transmission electron microscopy (TEM). The particle sizes of 150-200 active components were statistically analyzed and the average value was taken.
[0054] 2. CO2 conversion rate and CH4 selectivity
[0055] The inlet and outlet gas flow rates are determined by flow meters, and the gas components are determined by online gas chromatography. The percentage of each component is obtained by passing the reacted gas through the gas chromatograph, and then multiplied by the total flow rate of the reacted gas to obtain the content of each component after the reaction. Wherein:
[0056] CO2 conversion rate = [CO2(in) - CO2(out)] / CO2(in) * 100%;
[0057] CH4 selectivity = CH4(e) / [CO2(in) - CO2(e)] * 100%.
[0058] 3. Test of the catalyst's CO2 adsorption capacity
[0059] The adsorption capacity of the catalyst for CO2 was quantitatively tested by CO2 temperature-programmed desorption (CO2-TPD).
[0060] 4. Carbon Deposit Test
[0061] Thermogravimetric analysis (TG) was used to quantitatively test the carbon deposition on the catalyst after the reaction.
[0062] Example 1
[0063] (1) Weigh 563.42g of NaAlO2 and add it to 1000mL of deionized water. Stir thoroughly to dissolve it and obtain the first solution.
[0064] (2) Weigh 247.73g Ni(NO3)2·6H2O, 477.14g Mg(NO3)2·6H2O and 181g Al(NO3)3·9H2O, add them to 1000mL of deionized water and stir thoroughly to dissolve them to obtain the second solution;
[0065] (3) Transfer the second solution to a constant pressure funnel, and then add the second solution dropwise to the first solution while stirring. Continue stirring for 5 hours, and a precipitate will gradually form.
[0066] (4) After the precipitation in step (3) is complete, filter and wash the obtained precipitate three times; then, dry the obtained precipitate filter cake in a drying oven at 100°C for 10 hours.
[0067] (5) The dried sample was calcined in a muffle furnace at 500°C for 3 hours. The heating rate of the muffle furnace was 3°C / min. After cooling to room temperature, catalyst C1 was obtained. The active component in the catalyst exists in the form of oxides.
[0068] Example 2
[0069] (1) Weigh 111.07g of NaAlO2 and add it to 200mL of deionized water. Stir thoroughly to dissolve it and obtain the first solution.
[0070] (2) Weigh 74.32g Ni(NO3)2·6H2O, 63.62g Mg(NO3)2·6H2O and 43.52g Al(NO3)3·9H2O, add them to 200mL of deionized water and stir thoroughly to dissolve them to obtain the second solution;
[0071] (3) Transfer the second solution to a constant pressure funnel, and then add the second solution dropwise to the first solution while stirring. Continue stirring for 5 hours, and a precipitate will gradually form.
[0072] (4) After the precipitation in step (3) is complete, filter and wash the obtained precipitate three times; then, dry the obtained precipitate filter cake in a drying oven at 100°C for 12 hours.
[0073] (5) The dried sample was calcined in a muffle furnace at 600°C for 5 h with a heating rate of 5°C / min. After cooling to room temperature, catalyst C2 was obtained; wherein the active component in the catalyst exists in the form of oxides.
[0074] Example 3
[0075] (1) Weigh 103.31g of NaAlO2 and add it to 200mL of deionized water. Stir thoroughly to dissolve it and obtain the first solution.
[0076] (2) Weigh 99.09g Ni(NO3)2·6H2O, 63.17g Ca(NO3)2·4H2O and 5.48g Al(NO3)3·9H2O, add them to 200mL of deionized water and stir thoroughly to dissolve them to obtain the second solution;
[0077] (3) Transfer the second solution to a constant pressure funnel, and then add the second solution dropwise to the first solution while stirring. Continue stirring for 5 hours, and a precipitate will gradually form.
[0078] (4) After the precipitation in step (3) is complete, filter and wash the obtained precipitate three times; then, dry the obtained precipitate filter cake in a drying oven at 120°C for 12 hours.
[0079] (5) The dried sample was calcined in a muffle furnace at 450°C for 2 hours. The heating rate of the muffle furnace was 3°C / min. After cooling to room temperature, catalyst C3 was obtained. The active component in the catalyst exists in the form of oxides.
[0080] Example 4
[0081] (1) Weigh 112.55g of NaAlO2 and add it to 200mL of deionized water. Stir thoroughly to dissolve it and obtain the first solution.
[0082] (2) Weigh 61.73g Co(NO3)2·6H2O, 18.92g Ce(NO3)3·6H2O and 73.58g Al(NO3)3·9H2O, add them to 200mL of deionized water and stir thoroughly to dissolve them to obtain the second solution;
[0083] (3) Transfer the second solution to a constant pressure funnel, and then add the second solution dropwise to the first solution while stirring. Continue stirring for 5 hours, and a precipitate will gradually form.
[0084] (4) After the precipitation in step (3) is complete, filter and wash the obtained precipitate three times; then, dry the obtained precipitate filter cake in a drying oven at 120°C for 16 hours.
[0085] (5) The dried sample was calcined in a muffle furnace at 400°C for 3 hours. The heating rate of the muffle furnace was 3°C / min. After cooling to room temperature, catalyst C4 was obtained. The active component in the catalyst exists in the form of oxides.
[0086] Example 5
[0087] (1) Weigh 108.79g of NaAlO2 and add it to 200mL of deionized water. Stir thoroughly to dissolve it and obtain the first solution.
[0088] (2) Weigh 74.32g Ni(NO3)2·6H2O, 13.29g La(NO3)3·6H2O and 90.78g Al(NO3)3·9H2O, add them to 200mL of deionized water and stir thoroughly to dissolve them to obtain the second solution;
[0089] (3) Transfer the second solution to a constant pressure funnel, and then add the second solution dropwise to the first solution while stirring. Continue stirring for 5 hours, and a precipitate will gradually form.
[0090] (4) After the precipitation in step (3) is complete, filter and wash the obtained precipitate three times; then, dry the obtained precipitate filter cake in a drying oven at 120°C for 14 hours.
[0091] (5) The dried sample was calcined in a muffle furnace at 500°C for 3 hours. The heating rate of the muffle furnace was 5°C / min. After cooling to room temperature, catalyst C5 was obtained. The active component in the catalyst exists in the form of oxides.
[0092] Example 6
[0093] (1) Weigh 102.78g of NaAlO2 and add it to 200mL of deionized water. Stir thoroughly to dissolve it and obtain the first solution.
[0094] (2) Weigh 49.55g Ni(NO3)2·6H2O, 37.84g Ce(NO3)3·6H2O and 81.50g Al(NO3)3·9H2O, add them to 200mL of deionized water and stir thoroughly to dissolve them to obtain the second solution;
[0095] (3) Transfer the second solution to a constant pressure funnel, and then add the second solution dropwise to the first solution while stirring. Continue stirring for 5 hours, and a precipitate will gradually form.
[0096] (4) After the precipitation in step (3) is complete, filter and wash the obtained precipitate three times; then, dry the obtained precipitate filter cake in a drying oven at 120°C for 12 hours.
[0097] (5) The dried sample was calcined in a muffle furnace at 500°C for 3 hours. The heating rate of the muffle furnace was 3°C / min. After cooling to room temperature, catalyst C6 was obtained. The active component in the catalyst exists in the form of oxides.
[0098] Example 7
[0099] (1) Weigh 102.74g of NaAlO2 and add it to 200mL of deionized water. Stir thoroughly to dissolve it and obtain the first solution.
[0100] (2) Weigh 49.38g Co(NO3)2·6H2O, 37.84g Ce(NO3)3·6H2O and 81.68g Al(NO3)3·9H2O, add them to 200mL of deionized water and stir thoroughly to dissolve them to obtain the second solution;
[0101] (3) Transfer the second solution to a constant pressure funnel, and then add the second solution dropwise to the first solution while stirring. Continue stirring for 5 hours, and a precipitate will gradually form.
[0102] (4) After the precipitation in step (3) is complete, filter and wash the obtained precipitate three times; then, dry the obtained precipitate filter cake in a drying oven at 120°C for 12 hours.
[0103] (5) The dried sample was calcined in a muffle furnace at 500°C for 3 hours. The heating rate of the muffle furnace was 3°C / min. After cooling to room temperature, catalyst C7 was obtained. The active component in the catalyst exists in the form of oxides.
[0104] Comparative Example 1
[0105] (1) Weigh 49.55g Ni(NO3)2·6H2O and 37.84g Ce(NO3)3·6H2O and add them to 200mL of deionized water and stir thoroughly to dissolve.
[0106] (2) Add 75g of Al2O3 support to the solution obtained in step (1) and stir continuously until the solution and support are completely mixed. Place the sample in a drying oven at 120℃ and dry for 12h.
[0107] (3) The dried sample was calcined in a muffle furnace at 500°C for 3 hours. The heating rate of the muffle furnace was 3°C / min. After cooling to room temperature, catalyst D1 was obtained. The active component in the catalyst exists in the form of oxides.
[0108] Comparative Example 2
[0109] (1) Weigh 49.55g Ni(NO3)2·6H2O, 37.84g Ce(NO3)3·6H2O and 551.88g Al(NO3)3·9H2O and add them to 500mL of deionized water. Stir well to dissolve and obtain solution A.
[0110] (2) Weigh a certain amount of NaOH and Na2CO3 according to the molar ratio and dissolve them in 500ml of deionized water to obtain solution B;
[0111] (3) Add solutions A and B to the beaker at the same rate and stir continuously to keep the pH value of the system at 9.5 to 10.5, and then stir the solution at 60°C for 12 hours;
[0112] (4) Filter the solution and wash it until it is neutral. Dry the resulting precipitate in a drying oven at 110°C for 12 hours.
[0113] (5) The dried sample was calcined in a muffle furnace at 500°C for 3 hours. The heating rate of the muffle furnace was 3°C / min. After cooling to room temperature, catalyst D2 was obtained. The active component in the catalyst exists in the form of oxides.
[0114] Application examples
[0115] The catalysts C1 to C7, D1, and D2 prepared in Examples 1 to 7 and Comparative Examples 1 to 2 were subjected to methanation processes according to the following steps:
[0116] Catalyst particles of 40–60 mesh were packed into a fixed-bed reactor, and the reactor was purged with an H2 / N2 atmosphere at 500°C for 1 hour. During this process, the active components (nickel oxide or cobalt oxide) existing in oxide form were reduced to elemental form (nickel or cobalt). Subsequently, a CO2 / H2 feed gas with a CO2:H2 volume ratio of 1:4 was introduced for the reaction, with a space velocity of 40,000 h⁻¹. -1 The reaction was carried out at atmospheric pressure, at a temperature of 300℃, and for 50 hours. The reaction tail gas was condensed and dehydrated before being passed through an online gas chromatograph to detect its components and content. The CO2 conversion rate and CH4 selectivity were calculated using the aforementioned method.
[0117] The composition and test data of each catalyst are shown in Table 1.
[0118] Table 1
[0119]
[0120] Based on the descriptions of the various embodiments and comparative examples, and the data in Table 1, it can be seen that the main difference between Example 6 and Comparative Examples 1 and 2 lies in the different catalyst preparation methods. Comparative Examples 1 and 2 prepared catalysts by co-impregnation and co-precipitation methods, respectively. The results in Table 1 show that the particle size of the active component of catalyst C6 prepared in Example 6 (1.7 nm) is significantly smaller than that of the active components of catalysts D1 and D2 prepared in Comparative Examples 1 and 2 (8.8 nm and 5.8 nm, respectively). Furthermore, while maintaining high methane selectivity, the CO2 conversion rate and CO2 adsorption capacity of the reaction using catalyst C6 are significantly higher than those using catalysts D1 and D2. The carbon deposition of catalyst C6 after the reaction (1.3%) is significantly lower than that of catalysts D1 and D2 (8.3% and 4.6%, respectively). Simultaneously, the particle size change of the active component of catalyst C6 before and after the reaction (0.1 nm) is significantly smaller than that of catalysts D1 and D2 (2.6 nm and 0.8 nm, respectively).
[0121] Therefore, in the methanation process, the catalyst prepared by the embodiments of the present invention has better catalytic performance than the catalysts prepared by co-impregnation and co-precipitation methods, and also has excellent resistance to sintering and carbon deposition.
[0122] Furthermore, as shown in Table 1, the catalytic performance is better when the content of active component in catalysts C1 to C7 is 10 wt% and 12.5 wt%, respectively. Therefore, the content of active component in the catalyst is preferably 9 to 13 wt%.
[0123] Furthermore, as shown in Table 1, the catalyst with CeO2 as the additive has better CO2 adsorption capacity. Therefore, CeO2 is the preferred additive.
[0124] Based on the above results, the catalysts C1 to C7 prepared in Examples 1 to 7 of this invention have ultra-small particle sizes of active components and exhibit excellent catalytic performance for carbon dioxide methanation. For example, at a reaction temperature of 300°C, the CO2 conversion rate of the catalyst can reach over 95%, the selectivity for CH4 can reach 100%, and the CO2 adsorption capacity exceeds 0.9 mmol / g.
[0125] Unless otherwise specified, the terms used in this invention have the meanings commonly understood by those skilled in the art.
[0126] The embodiments described in this invention are for illustrative purposes only and are not intended to limit the scope of protection of this invention. Those skilled in the art can make various other substitutions, changes and improvements within the scope of this invention. Therefore, this invention is not limited to the above embodiments, but is only defined by the claims.
Claims
1. A method for preparing a catalyst, comprising the following steps: The anions and cations undergo a double hydrolysis reaction to form a precipitate; and The precipitate was separated from the solution system and calcined to obtain the catalyst; in, The anion includes aluminate ions, and the cation includes active metal ions, carrier metal ions, and auxiliary metal ions; the active metal ions include nickel ions and / or cobalt ions, the carrier metal ions include aluminum ions, and the auxiliary metal ions include one or more of magnesium ions, calcium ions, cerium ions, and lanthanum ions.
2. The preparation method according to claim 1, comprising: The precipitate is prepared by reacting aluminate solution with a soluble salt solution. Subsequently, the precipitate was separated from the solution system and then dried and calcined. The aluminate solution contains the anion, and the soluble salt solution contains the cation.
3. The preparation method according to claim 2, wherein, The raw materials for preparing the aluminate solution include sodium aluminate; the raw materials for preparing the soluble salt solution include nitrates and / or hydrates of active metals, aluminum nitrates and / or hydrates of aluminum nitrates and / or hydrates of auxiliary metals.
4. The preparation method according to claim 3, wherein, The nitrates and / or hydrates of the active metal include one or more of Ni(NO3)2, Ni(NO3)2·6H2O, Co(NO3)2, and Co(NO3)2·6H2O; and / or, The nitrate and / or hydrate of the auxiliary metal includes one or more of Mg(NO3)2, Mg(NO3)2·6H2O, Ca(NO3)2, Ca(NO3)2·4H2O, Ce(NO3)3, Ce(NO3)3·6H2O, La(NO3)3, and La(NO3)3·6H2O; and / or, The aluminum nitrate and / or its hydrates include Al(NO3)3 and / or Al(NO3)3·9H2O.
5. The preparation method according to claim 2, wherein, The drying process is performed at a temperature of 100–120°C; and / or, The drying process takes 10 to 20 hours.
6. The preparation method according to claim 1, wherein, The calcination treatment temperature is 400–600°C; and / or, The roasting process takes 1 to 5 hours.
7. A catalyst prepared by any one of claims 1 to 6.
8. The catalyst according to claim 7, comprising 9-20 wt% of an active component; wherein, The active component includes one or more of Ni and / or its oxides, Co and / or its oxides, the support is Al2O3, and the auxiliary agent includes one or more of MgO, CaO, CeO2, and La2O3.
9. The catalyst according to claim 7, wherein, The particle size of the active component is 1.5–3.5 nm; and / or, The catalyst comprises 9–13 wt% of an active component; and / or, The catalyst comprises 65-85 wt% of the support and 5-15 wt% of the auxiliary agent.
10. The use of the catalyst according to any one of claims 7 to 9 in the carbon dioxide methanation process.