Nickel-based solid solution catalyst as well as preparation method and application thereof

Abstract

The invention provides a nickel-based solid solution catalyst as well as a preparation method and application thereof, and relates to the technical field of methane reforming. The chemical formula of the nickel-based solid solution catalyst is Nix-M1-x-O, wherein M is alkaline metal; the value range of x is from 0.02 to 0.3. According to the nickel-based solid solution catalyst provided by the invention, alkaline sites provided by the alkaline metal can effectively promote adsorption and activation of CO2, so that the adsorption capacity of the catalyst to reactants is enhanced, and the activity of a catalytic reaction is improved. Meanwhile, the alkaline sites can promote rapid oxidation of a carbon deposition precursor and effectively inhibit generation of carbon deposition, so that the service life of the catalyst is prolonged, and the efficient performance of the catalyst is kept. Through the application of the catalyst, the reaction efficiency of preparing synthesis gas by reforming methane with carbon dioxide is remarkably improved, meanwhile, the risk of catalyst deactivation caused by carbon deposition in the reaction process is reduced, and a more efficient and more economical solution is provided for industrial application.

Description

Technical Field

[0001] The invention relates to the technical field of methane reforming, and in particular to a nickel-based solid solution catalyst and a preparation method and application thereof. Background Art

[0002] The carbon dioxide reforming to methane reaction (DRM, CH4+CO2→2CO+2H2) is a reaction that converts two major greenhouse gases into synthesis gas (CO and H2), which has significant economic and environmental benefits. Synthesis gas is an important raw material for the Fischer-Tropsch synthesis reaction and can be used to prepare liquid fuels, alcohols, acids and other high-value-added chemicals. In this way, DRM not only helps to mitigate the greenhouse effect, but also converts industrial waste gas into valuable resources, helping to achieve the "dual carbon" goal.

[0003] The DRM reaction is a highly endothermic process and usually requires high temperature conditions to proceed. The use of catalysts can significantly reduce the reaction temperature and improve the reaction efficiency. At present, DRM catalysts are mainly divided into precious metal catalysts (such as Pd, Ru, Rh, etc.) and transition metal catalysts (such as Ni, Co, Fe, etc.). Among them, Ni-based catalysts are considered to be the most promising choice for industrialization due to their high catalytic activity, low price and abundant resources.

[0004] However, the main challenge faced by Ni-based catalysts in DRM reactions is the carbon deposition problem. Carbon deposition will cover the active sites of the catalyst, causing catalyst deactivation and reducing reaction efficiency. Studies have shown that the formation of carbon deposition mainly comes from the deep cracking of methane. In practical applications, the performance optimization of Ni-based catalysts needs to consider not only activity and resistance to carbon deposition, but also its long-term stability under industrial conditions.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] One of the purposes of the present invention is to provide a nickel-based solid solution catalyst to solve at least one of the above-mentioned technical problems in the prior art.

[0007] A second object of the present invention is to provide a method for preparing a nickel-based solid solution catalyst.

[0008] A third object of the present invention is to provide an application of a nickel-based solid solution catalyst.

[0009] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0010] The first aspect of the present invention provides a nickel-based solid solution catalyst having a chemical formula of Ni x -M 1-x -O;

[0011] Wherein, M is an alkaline metal; and the value range of x is 0.02 to 0.3.

[0012] Furthermore, the alkaline metal includes a mandatory first alkaline metal and an optional second alkaline metal.

[0013] Preferably, the first alkaline metal is Mg.

[0014] Preferably, the second alkaline metal includes at least one of Ca, Zr and Ce.

[0015] Furthermore, the value range of x is 0.05 to 0.25.

[0016] The second aspect of the present invention provides a method for preparing the nickel-based solid solution catalyst, comprising adding a template, a soluble nickel salt, a soluble M salt and a complexing agent into deionized water, mixing them evenly and reacting them; after the reaction is completed, drying and calcining are performed to obtain the nickel-based solid solution catalyst.

[0017] Furthermore, the template comprises a PEO-PPO-PEO triblock copolymer.

[0018] Preferably, the grade of the PEO-PPO-PEO triblock copolymer includes at least one of P123, F127 and F108.

[0019] Furthermore, the soluble nickel salt includes at least one of nickel nitrate, nickel sulfate, nickel chloride and nickel acetate.

[0020] Preferably, the soluble M salt comprises a mandatory soluble magnesium salt and an optional soluble second alkaline metal salt.

[0021] Preferably, the soluble magnesium salt includes at least one of magnesium sulfate, magnesium chloride, magnesium nitrate and magnesium acetate.

[0022] Preferably, the soluble second alkaline metal salt includes at least one of a soluble calcium salt, a soluble zirconium salt, and a soluble cerium salt.

[0023] Preferably, the soluble calcium salt includes at least one of calcium chloride, calcium nitrate, calcium dihydrogen phosphate and calcium bicarbonate.

[0024] Preferably, the soluble zirconium salt comprises at least one of zirconium chloride, zirconium nitrate and zirconium acetate.

[0025] Preferably, the soluble cerium salt includes at least one of cerium chloride, cerium nitrate and cerium acetate.

[0026] Furthermore, the complexing agent includes at least one of citric acid, oxalic acid, and ethylenediaminetetraacetic acid, preferably citric acid.

[0027] Furthermore, the molar ratio of nickel in the soluble nickel salt to M in the soluble M salt is x:(1-x); wherein x ranges from 0.02 to 0.3.

[0028] Preferably, the molar ratio of the template to the metal cation is 1:20-100.

[0029] Preferably, the molar ratio of the complexing agent to the metal cation is 0.1-3.

[0030] Preferably, the reaction temperature is 40-80° C. and the reaction time is 2-8 hours.

[0031] Preferably, the drying temperature is 90-130° C. and the drying time is 2-18 hours.

[0032] Preferably, the calcination temperature is 600-900° C. and the calcination time is 2-7 hours.

[0033] Preferably, the heating rate of the calcination is 1 to 10°C / min.

[0034] The third aspect of the present invention provides the use of the nickel-based solid solution catalyst in the reforming of methane with carbon dioxide to produce synthesis gas.

[0035] Furthermore, the catalyst is used in an amount with a space velocity of 36000 mL / g·h.

[0036] Compared with the prior art, the present invention has at least the following beneficial effects:

[0037] The nickel-based solid solution catalyst provided by the present invention, the alkaline sites provided by the alkaline metal can effectively promote the adsorption and activation of CO2, thereby enhancing the adsorption capacity of the catalyst to the reactant and improving the activity of the catalytic reaction. At the same time, these alkaline sites can also promote the rapid oxidation of carbon deposit precursors, effectively inhibit the generation of carbon deposits, thereby extending the service life of the catalyst and maintaining its high efficiency. In addition, through the precise regulation of the ordered mesoporous structure, the specific surface area and pore structure of the catalyst are optimized, further improving the dispersibility and accessibility of the active component Ni, and enhancing the contact efficiency between the catalyst and the reactant. The synergistic effect of this structural optimization and the alkaline sites makes the catalyst significantly inhibit the generation of carbon deposits while strengthening the catalytic activity, and realizes the synergistic enhancement of catalytic performance. Therefore, the catalyst not only shows excellent catalytic efficiency, but also has good stability and anti-carbon deposition ability, showing a broad application prospect.

[0038] The preparation method provided by the present invention can effectively regulate the pore structure and metal dispersion of the catalyst through the synergistic effect of the template and the complexing agent, thereby increasing the specific surface area of ​​the catalyst and the exposure degree of the active sites. At the same time, the introduction of the alkaline metal not only enhances the adsorption and activation ability of the catalyst to CO2, but also promotes the rapid oxidation of the carbon deposit precursor, significantly inhibiting the formation of carbon deposits. In addition, the method further optimizes the structure and stability of the catalyst by accurately controlling the post-processing steps such as calcination, so that it can still maintain good catalytic activity and anti-sintering performance under high temperature conditions. This preparation method realizes efficient preparation and performance optimization of the catalyst.

[0039] The application provided by the present invention, in view of the advantages of the above-mentioned nickel-based solid solution catalyst, provides a catalyst with better performance for the production of synthesis gas by reforming methane with carbon dioxide. Through the application of this catalyst, the reaction efficiency of the production of synthesis gas by reforming methane with carbon dioxide is significantly improved, while the risk of catalyst deactivation caused by carbon deposition during the reaction is reduced, providing a more efficient and economical solution for industrial applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 The XRD pattern obtained for characterization example 1;

[0042] Figure 2 To characterize the H2-TPR curve obtained in Example 2;

[0043] Figure 3 To characterize the CO2-TPD curve obtained in Example 3;

[0044] Figure 4 Ni 2p XPS spectrum obtained for characterization example 4;

[0045] Figure 5 a in the figure is the CO2 conversion rate curve obtained in Test Example 3. Figure 5 b is the CH4 conversion rate curve obtained in Test Example 3;

[0046] Figure 6 a in the figure is the N2 adsorption-desorption curve obtained in Test Example 4. Figure 6 b in the figure is the pore size distribution diagram obtained in Test Example 4. Figure 6 c in the figure is the N2 adsorption-desorption curve obtained in Test Example 4;

[0047] Figure 7 This is the oxygen thermogravimetric curve obtained in Characterization Example 5. DETAILED DESCRIPTION

[0048] The embodiments of the present invention will be described in detail below in conjunction with the embodiments and examples, but those skilled in the art will understand that the following embodiments and examples are only used to illustrate the present invention and should not be considered to limit the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0049] The first aspect of the present invention provides a nickel-based solid solution catalyst having a chemical formula of Ni x -M 1-x -O;

[0050] Wherein, M is an alkaline metal; and the value range of x is 0.02 to 0.3.

[0051] The nickel-based solid solution catalyst provided by the present invention, the alkaline sites provided by the alkaline metal can effectively promote the adsorption and activation of CO2, thereby enhancing the adsorption capacity of the catalyst to the reactant and improving the activity of the catalytic reaction. At the same time, these alkaline sites can also promote the rapid oxidation of carbon deposit precursors, effectively inhibit the generation of carbon deposits, thereby extending the service life of the catalyst and maintaining its high efficiency. In addition, through the precise regulation of the ordered mesoporous structure, the specific surface area and pore structure of the catalyst are optimized, further improving the dispersibility and accessibility of the active component Ni, and enhancing the contact efficiency between the catalyst and the reactant. The synergistic effect of this structural optimization and the alkaline sites makes the catalyst significantly inhibit the generation of carbon deposits while strengthening the catalytic activity, and realizes the synergistic enhancement of catalytic performance. Therefore, the catalyst not only shows excellent catalytic efficiency, but also has good stability and anti-carbon deposition ability, showing a broad application prospect.

[0052] Typically, but not limiting, the chemical formula of the nickel-based solid solution catalyst may be Ni 0.02 -M 0.98 -O、Ni 0.05 -M 0.95 -O、Ni 0.1 -M 0.9 -O、Ni 0.15 -M 0.85 -O、Ni 0.2 -M 0.8 -O、Ni 0.25 -M 0.75 -O、Ni 0.3 -M 0.7 -O.

[0053] Furthermore, the alkaline metal includes a mandatory first alkaline metal and an optional second alkaline metal.

[0054] It should be noted that "mandatory" refers to the components or elements that must be included in the alkaline metal. It emphasizes that a certain component is indispensable and cannot be omitted. "Optional" refers to the components or elements that can be selectively added to the alkaline metal. It emphasizes that a certain component is not necessary and can be added or not added according to needs or specific conditions.

[0055] Preferably, the first alkaline metal is Mg.

[0056] Preferably, the second alkaline metal includes at least one of Ca, Zr and Ce.

[0057] Furthermore, the value range of x is 0.05 to 0.25.

[0058] The second aspect of the present invention provides a method for preparing the nickel-based solid solution catalyst, comprising adding a template, a soluble nickel salt, a soluble M salt and a complexing agent into deionized water, mixing them evenly and reacting them; after the reaction is completed, drying and calcining are performed to obtain the nickel-based solid solution catalyst.

[0059] The preparation method provided by the present invention can effectively regulate the pore structure and metal dispersion of the catalyst through the synergistic effect of the template and the complexing agent, thereby increasing the specific surface area of ​​the catalyst and the exposure degree of the active sites. At the same time, the introduction of the alkaline metal not only enhances the adsorption and activation ability of the catalyst to CO2, but also promotes the rapid oxidation of the carbon deposit precursor, significantly inhibiting the formation of carbon deposits. In addition, the method further optimizes the structure and stability of the catalyst by accurately controlling the post-processing steps such as calcination, so that it can still maintain good catalytic activity and anti-sintering performance under high temperature conditions. This preparation method realizes efficient preparation and performance optimization of the catalyst.

[0060] Furthermore, the template comprises a PEO-PPO-PEO triblock copolymer.

[0061] Preferably, the grade of the PEO-PPO-PEO triblock copolymer includes at least one of P123, F127 and F108.

[0062] Furthermore, the soluble nickel salt includes at least one of nickel nitrate, nickel sulfate, nickel chloride and nickel acetate.

[0063] Preferably, the soluble M salt comprises a mandatory soluble magnesium salt and an optional soluble second alkaline metal salt.

[0064] Preferably, the soluble magnesium salt includes at least one of magnesium sulfate, magnesium chloride, magnesium nitrate and magnesium acetate.

[0065] Preferably, the soluble second alkaline metal salt includes at least one of a soluble calcium salt, a soluble zirconium salt, and a soluble cerium salt.

[0066] Preferably, the soluble calcium salt includes at least one of calcium chloride, calcium nitrate, calcium dihydrogen phosphate and calcium bicarbonate.

[0067] Preferably, the soluble zirconium salt comprises at least one of zirconium chloride, zirconium nitrate and zirconium acetate.

[0068] Preferably, the soluble cerium salt includes at least one of cerium chloride, cerium nitrate and cerium acetate.

[0069] Furthermore, the complexing agent includes at least one of citric acid, oxalic acid, and ethylenediaminetetraacetic acid, preferably citric acid.

[0070] Furthermore, the molar ratio of nickel in the soluble nickel salt to M in the soluble M salt is x:(1-x); wherein x ranges from 0.02 to 0.3.

[0071] Preferably, the molar ratio of the template to the metal cation is 1:20-100.

[0072] The metal cation refers to the nickel in the soluble nickel salt and the M in the soluble M salt. Typically but not limiting, the molar ratio of the template to the metal cation can be, for example, 1:20, 1:30, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90, 1:100.

[0073] Preferably, the molar ratio of the complexing agent to the metal cation is 0.1 to 3. Typically but not limiting, the molar ratio of the complexing agent to the metal cation may be, for example, 0.1, 0.5, 1, 1.5, 2, 2.5 or 3.

[0074] Preferably, the reaction temperature is 40-80° C. and the reaction time is 2-8 hours.

[0075] Typically but not limiting, the reaction temperature can be, for example, 40°C, 50°C, 60°C, 70°C, 80°C, or any value within the range of 40°C to 80°C; the reaction time can be, for example, 2h, 3h, 4h, 5h, 6h, 7h or 8h, or any value within the range of 2h to 8h.

[0076] Preferably, the drying temperature is 90-130° C. and the drying time is 2-18 hours.

[0077] Typically but not limitatively, the drying temperature may be, for example, 90°C, 100°C, 110°C, 120°C, 130°C, or any value within the range of 90°C to 130°C; the drying time may be, for example, 2h, 4h, 8h, 10h, 12h, 14h, 16h, 18h, or any value within the range of 2h to 18h.

[0078] Preferably, the calcination temperature is 600-900° C. and the calcination time is 2-7 hours.

[0079] Typically but not limitatively, the calcination temperature may be, for example, 600°C, 650°C, 750°C, 760°C, 770°C, 780°C, 790°C, 800°C, 810°C, 820°C, 830°C, 840°C, 850°C, 860°C or 900°C, or any value within the range of 600°C to 900°C; the calcination time may be, for example, 2h, 3h, 4h, 5h, 6h, 7h, or any value within the range of 2h to 7h.

[0080] Preferably, the heating rate of the calcination is 1 to 10°C / min.

[0081] Typically but not limitatively, the heating rate of calcination can be, for example, 1°C / min, 2°C / min, 3°C / min, 4°C / min, 5°C / min, 6°C / min, 8°C / min, 10°C / min, or any value within the range of 1°C / min to 10°C / min.

[0082] The third aspect of the present invention provides the use of the nickel-based solid solution catalyst in the reforming of methane with carbon dioxide to produce synthesis gas.

[0083] Furthermore, the catalyst is used at a space velocity of 36000 mL / g·h.

[0084] The application provided by the present invention, in view of the advantages of the above-mentioned nickel-based solid solution catalyst, provides a catalyst with better performance for the production of synthesis gas by reforming methane with carbon dioxide. Through the application of this catalyst, the reaction efficiency of the production of synthesis gas by reforming methane with carbon dioxide is significantly improved, while the risk of catalyst deactivation caused by carbon deposition during the reaction is reduced, providing a more efficient and economical solution for industrial applications.

[0085] The present invention is further described below by specific examples and comparative examples, but it should be understood that these examples are only used for more detailed description and should not be understood as limiting the present invention in any form. The raw materials used in the examples and comparative examples of the present invention, if no specific conditions are specified, are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used without indicating the manufacturer are all conventional products that can be purchased commercially.

[0086] Example 1

[0087] This embodiment provides a nickel-based solid solution catalyst, and the preparation method is as follows: 2.32g of polymer PEO-PPO-PEO (brand name P123), 0.291g of Ni(NO3)2·6H2O, 7.19g of Mg(NO3)2.6(H2O), and 5.76g of anhydrous citric acid are dissolved in 20ml of deionized water and stirred for 1h. After standing at 60℃ for 4h, it is dried at 100℃ for 12h, heated at 1℃ / min, and calcined at 800℃ in air atmosphere for 5h. Ni 0.05 -Mg 0.95 -O catalyst (Ni:Mg molar ratio of 5:95).

[0088] Example 2

[0089] This embodiment provides a nickel-based solid solution catalyst. The difference from Example 1 is that the amount of raw materials is adjusted, and the Ni:Mg molar ratio is adjusted to 10:90. The remaining raw material amounts and process methods are the same as those in Example 1 and are not repeated here.

[0090] Example 3

[0091] This embodiment provides a nickel-based solid solution catalyst. The difference from Example 1 is that the amount of raw materials is adjusted, and the Ni:Mg molar ratio is adjusted to 15:85. The remaining raw material amounts and process methods are the same as those in Example 1 and are not repeated here.

[0092] Example 4

[0093] This embodiment provides a nickel-based solid solution catalyst. The difference from Example 1 is that the amount of raw materials is adjusted, and the Ni:Mg molar ratio is adjusted to 20:80. The remaining raw material amounts and process methods are the same as those in Example 1 and are not repeated here.

[0094] Example 5

[0095] This embodiment provides a nickel-based solid solution catalyst. The difference from Example 1 is that the amount of raw materials is adjusted, and the Ni:Mg molar ratio is adjusted to 25:75. The remaining raw material amounts and process methods are the same as those in Example 1 and are not repeated here.

[0096] Example 6

[0097] This embodiment provides a nickel-based solid solution catalyst. The difference from Embodiment 3 is that the brand of the polymer PEO-PPO-PEO is replaced by F127, and the remaining raw materials and process methods are the same as those in Embodiment 3, which will not be described again.

[0098] Example 7

[0099] This embodiment provides a nickel-based solid solution catalyst. The difference from Example 3 is that calcium chloride is added in the feeding stage to control the Ni:Mg:Ca molar ratio to 15:80:5. The remaining raw material amounts and process methods are the same as those in Example 3 and are not described again here.

[0100] Example 8

[0101] This embodiment provides a nickel-based solid solution catalyst. The difference from Embodiment 3 is that the calcination temperature is 850° C., and the remaining raw material amounts and process methods are the same as those in Embodiment 3, which will not be described again.

[0102] Example 9

[0103] This embodiment provides a nickel-based solid solution catalyst. The difference from Embodiment 3 is that the calcination temperature is 900° C., and the remaining raw material amounts and process methods are the same as those in Embodiment 3, which will not be repeated here.

[0104] Example 10

[0105] This embodiment provides a nickel-based solid solution catalyst. The difference from Embodiment 3 is that zirconium chloride is added in the feeding stage, and the molar ratio of Ni:Mg:Zr is controlled to 15:80:5. The remaining raw material amounts and process methods are the same as those in Embodiment 3 and are not described again here.

[0106] Embodiment 11

[0107] This embodiment provides a nickel-based solid solution catalyst. The difference from Example 3 is that cerium chloride is added in the feeding stage, and the Ni:Mg:Ce molar ratio is controlled to 15:83:2. The remaining raw material amounts and process methods are the same as those in Example 3 and are not repeated here.

[0108] Example 12

[0109] This embodiment provides a nickel-based solid solution catalyst. The difference from Example 3 is that 0.875 g of oxalic acid is used instead of citric acid. The remaining raw materials and methods are the same as those in Example 3 and are not described again here.

[0110] Comparative Example 1

[0111] This comparative example provides a nickel-based supported catalyst, and the preparation method is as follows:

[0112] 1. Take 2.32g of polymer PEO-PPO-PEO (P123), 4.35g of Mg (NO3) 2.6 (H2O), and 5.76g of anhydrous citric acid and dissolve them in 20ml of deionized water, and stir for 1h. After standing at 60℃ for 4h, dry at 100℃ for 12h, increase the temperature at 1℃ / min, and calcine at 800℃ in air atmosphere for 5h to obtain MgO.

[0113] 2. Take 0.68g of the prepared MgO sample and 0.87g of Ni(NO3)2·6H2O, disperse them in 20ml of deionized water, and stir for 1h. After standing at 25℃ for 24h, dry them at 100℃ for 12h, increase the temperature at 5℃ / min, and calcine them at 800℃ in air atmosphere for 5h. 0.15 / MgO catalyst.

[0114] Comparative Example 2

[0115] This comparative example provides a nickel-based solid solution catalyst. The difference from Example 3 is that cobalt chloride is added in the feeding stage, and the Ni:Mg:Co molar ratio is controlled to 15:80:5. The remaining raw material amounts and process methods are the same as those in Example 3 and are not described again here.

[0116] Comparative Example 3

[0117] This comparative example provides a nickel oxide catalyst, and the preparation method is as follows:

[0118] Take 2.32g of polymer PEO-PPO-PEO (P123), 0.87g of Ni(NO3)2·6H2O, and 5.76g of anhydrous citric acid and dissolve them in 20ml of deionized water, and stir for 1h. After standing at 60℃ for 4h, dry at 100℃ for 12h, increase the temperature at 1℃ / min, and calcine at 800℃ in air atmosphere for 5h to obtain NiO.

[0119] Characterization Example 1

[0120] The catalysts obtained in Example 3 and Comparative Example 1 were subjected to XRD, and the obtained spectra were as follows: Figure 1 shown.

[0121] from Figure 1 It can be seen that the crystal phase structure of the catalyst has changed significantly. It can be seen that the Ni 0.15 -Mg 0.85 During the preparation of the -O catalyst, part of the Ni species entered the MgO lattice.

[0122] Characterization Example 2

[0123] The NiO obtained in Comparative Example 3 and the Ni 0.15 -Mg 0.85-O, Ni obtained in Comparative Example 1 0.15 / MgO and the intermediate product MgO of Comparative Example 1 were subjected to H2-TPR (hydrogen programmed temperature reduction), and the obtained H2-TPR curve is as follows Figure 2 shown.

[0124] from Figure 2 It can be seen that the reduction temperatures of NiO on catalysts prepared by different preparation methods are quite different. It can be inferred that the occurrence states of NiO on the catalysts are quite different, and the products (existence states of Ni species) after reduction at the same temperature are somewhat different.

[0125] Characterization Example 3

[0126] The catalysts obtained in Example 3 and Comparative Example 1 were subjected to CO2-TPD (carbon dioxide temperature programmed desorption), and the obtained CO2-TPD curves were as follows: Figure 3 shown.

[0127] from Figure 3 It can be seen that Ni 0.15 -Mg 0.85 -O has a stronger adsorption capacity for the reactant CO2, which is one of the reasons why its catalyst performance is better.

[0128] Characterization Example 4

[0129] The catalysts obtained in Example 3 and Comparative Example 1 were subjected to Ni 2p XPS spectra, and the obtained spectra were as follows: Figure 4 shown.

[0130] from Figure 4 It can be seen that after the catalysts prepared by different preparation methods are reduced, the valence states of the active Ni species are quite different. 0.15 The Ni species on the surface of MgO is mainly Ni 2+ and Ni 0 In Example 3, the Ni species exists in the form of Ni δ+ and Ni 0 Therefore, different preparation methods lead to large differences in the physical structure and chemical state of the catalyst, which in turn leads to large differences in activity.

[0131] Test Example 1

[0132] The specific surface area of ​​the catalysts obtained in the examples and comparative examples was measured using a Huasi Instrument FD-2000. The data obtained are shown in Table 1 below.

[0133] Test Example 2

[0134] The catalysts obtained in the examples and comparative examples were used to carry out methane reforming experiments. The specific experimental methods are as follows:

[0135] 0.10 g of the catalyst was placed in a microreactor, the Ar atmosphere was heated to 800°C or 550°C, and a hydrogen atmosphere was introduced for reduction for 1 hour. Then, the reaction gas (CH4:CO2:Ar=1:1:2, F=60 ml / min) was introduced, and the reaction temperature was 800°C or 550°C. After the reaction was completed, the conversion rate was statistically analyzed. The data obtained are shown in Table 1 below.

[0136] Table 1

[0137]

[0138] Test Example 3

[0139] The catalysts obtained in Example 3 and Comparative Example 1 were used to conduct methane reforming experiments. The test temperature was adjusted to 550° C. The remaining test process parameters were the same as those in Test Example 2 and will not be described in detail herein.

[0140] The conversion rates of CO2 and CH4 in the process are calculated, and the obtained curve is as follows Figure 5 shown.

[0141] from Figure 5 It can be seen that Example 3 exhibits excellent DRM reaction activity. At 750°C, the conversion rates of CH4 and CO2 are maintained at around 97% and 95%, respectively, and remain stable during the 100h reaction. However, the catalyst of Comparative Example 1 is not only low in activity, but also deactivated after 4h of reaction.

[0142] Test Example 4

[0143] The catalysts obtained in the examples and comparative examples were subjected to N2 adsorption and desorption tests. The obtained N2 adsorption and desorption curves and pore size distribution diagrams are shown in FIG. Figure 6 shown.

[0144] from Figure 6 It can be seen that all catalysts exhibit a typical mesoporous structure.

[0145] Characterization Example 5

[0146] The catalyst after the reaction in Test Example 2 was subjected to an oxygen thermogravimetric (O2-TG) test, and the obtained oxygen thermogravimetric curve is as follows: Figure 7 As shown. It can be seen that the Ni 0.15 -Mg 0.85 The amount of byproduct carbon deposits on -O is significantly less.

[0147] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A nickel-based solid solution catalyst, characterized in that The chemical formula is Ni x -M 1-x -O; Wherein, M is an alkaline metal; and the value range of x is 0.02 to 0.

3.

2. The nickel-based solid solution catalyst according to claim 1, characterized in that The alkaline metal includes a first alkaline metal and / or an optional second alkaline metal; Preferably, the first alkaline metal is Mg; Preferably, the second alkaline metal includes at least one of Ca, Zr and Ce.

3. The nickel-based solid solution catalyst according to claim 1 or 2, characterized in that The value range of x is 0.05~0.

25.

4. A method for preparing a nickel-based solid solution catalyst according to any one of claims 1 to 3, characterized in that: The template, soluble nickel salt, soluble M salt and complexing agent are added into deionized water, mixed evenly and reacted; after the reaction is completed, drying and calcining are performed to obtain the nickel-based solid solution catalyst.

5. The preparation method according to claim 4, characterized in that: The template comprises a PEO-PPO-PEO triblock copolymer; Preferably, the grade of the PEO-PPO-PEO triblock copolymer includes at least one of P123, F127 and F108.

6. The preparation method according to claim 4, characterized in that: The soluble nickel salt includes at least one of nickel nitrate, nickel sulfate, nickel chloride and nickel acetate; Preferably, the soluble M salt comprises a required soluble magnesium salt and an optional soluble second alkaline metal salt; Preferably, the soluble magnesium salt includes at least one of magnesium sulfate, magnesium chloride, magnesium nitrate and magnesium acetate; Preferably, the soluble second alkaline metal salt includes at least one of a soluble calcium salt, a soluble zirconium salt, and a soluble cerium salt; Preferably, the soluble calcium salt includes at least one of calcium chloride, calcium nitrate, calcium dihydrogen phosphate and calcium bicarbonate; Preferably, the soluble zirconium salt comprises at least one of zirconium chloride, zirconium nitrate and zirconium acetate; Preferably, the soluble cerium salt includes at least one of cerium chloride, cerium nitrate and cerium acetate.

7. The preparation method according to claim 4, characterized in that: The complexing agent includes at least one of citric acid, oxalic acid, and ethylenediaminetetraacetic acid, preferably citric acid.

8. The preparation method according to any one of claims 4 to 7, characterized in that: The molar ratio of nickel in the soluble nickel salt to M in the soluble M salt is x:(1-x); wherein x ranges from 0.02 to 0.3; Preferably, the molar ratio of the template to the metal cation is 1:20 to 100; Preferably, the molar ratio of the complexing agent to the metal cation is 0.1 to 3; Preferably, the reaction temperature is 40-80°C and the reaction time is 2-8h; Preferably, the drying temperature is 90-130°C and the drying time is 2-18 hours; Preferably, the calcination temperature is 600-900°C and the time is 2-7h; Preferably, the heating rate of the calcination is 1 to 10°C / min.

9. Use of the nickel-based solid solution catalyst according to any one of claims 1 to 3 in reforming methane with carbon dioxide to produce synthesis gas.

10. The use according to claim 9, characterized in that: The amount of the catalyst used is 36000 mL / g·h in space velocity.

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