A micro / inter-mesoporous siliceous zeolite molecular sieve supported Ni / Ru catalyst based on magnesium-containing natural minerals, and a preparation method and application thereof

Abstract

The application discloses a kind of micro / intermediate pore siliceous zeolite molecular sieve load Ni / Ru catalyst based on magnesium-containing natural mineral and its preparation method and application, belong to the technical field of preparation and its application of inorganic catalytic material, the micro / intermediate pore siliceous zeolite molecular sieve prepared with magnesium-containing natural mineral is carrier, auxiliary noble metal Ru is introduced, constructs Ni-Ru bimetallic catalytic system, regulates active center dispersity, finally forms the composite material of bimetallic-micro / intermediate pore SiO2 molecular sieve.The catalyst of the application shows excellent reaction performance in CO2 conversion rate, CH4 conversion rate and H2 / CO ratio, etc., under the condition that volume space velocity (GHSV) is 39000mL·g ‑1 ·h ‑1 Under the condition that volume space velocity (GHSV) is 39000mL·g , CH4 conversion rate, CO2 conversion rate reaches 90% and 96% respectively, and exhibits significant anti-coking capacity and structural stability in 40h stability test, which provides a solid foundation for subsequent industrial amplification and engineering integration.

Description

Technical Field

[0001] This invention belongs to the field of inorganic catalytic materials preparation and application technology, and particularly relates to a Ni / Ru catalyst supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals, its preparation method and application. Background Technology

[0002] Dry reforming (DRM) of methane is a highly valuable industrial pathway for carbon resource conversion, converting methane and carbon dioxide into syngas. It offers dual benefits of energy production and environmental emission reduction, and has broad application prospects in chemical fields such as Fischer-Tropsch synthesis and methanol production. However, the DRM reaction is carried out at high temperatures (700–900°C) in a strong alternating reduction-oxidation atmosphere. Traditional catalysts face three major challenges: sintering of active sites, carbon deposition, and collapse of the support structure, which severely restricts its large-scale industrial application.

[0003] To overcome the above difficulties, selecting an excellent catalyst support is crucial. CN104399471A mentions a nickel-based catalyst and its molding method and application, which includes a modifier MgO and a support SiO2. The addition of the modifier (or catalyst aid) can effectively improve the chemical bonding between the support and the active component. However, SiO2 supports have insufficient thermal stability and are prone to sintering and agglomeration at high temperatures, reducing their specific surface area (Zhang Rongjun, Xia Guofu, Li Mingfeng, et al. Effect of support type on the performance of Ni-based catalysts in methane dry reforming [J]. Journal of Fuel Chemistry, 2015, 43(11): 1359-1365.). Although MgO can inhibit carbon deposition through alkaline sites, its small specific surface area and simple pore structure cannot provide sufficient dispersion sites for active metals, making it difficult to balance catalytic activity and stability (Li Zhenwei, Li Yufeng, Chen Jie, et al. Study on the performance of Ni-based catalysts in methane dry reforming by regulating support morphology [J]. Low Carbon Chemistry and Chemical Engineering, 2024, 49(08): 57-65.). Therefore, developing novel support materials with high specific surface area, suitable alkalinity, excellent thermal stability and structural stability has become a key direction for optimizing methane dry reforming catalysts.

[0004] Zeolite molecular sieves have attracted much attention in the field of heterogeneous catalysis due to their unique regular pore structure, high specific surface area, tunable acidity / basicity, and excellent thermal stability. Among them, zeolite molecular sieves such as ZSM-5, Beta, and MCM-41 can achieve precise control of surface properties through framework atom substitution or atomic doping. CN113477273A discloses a process for using molecular sieves as Ni and Ru supports, and the prepared catalysts exhibit good metal dispersion and strong metal-support interactions, ultimately yielding catalytic materials with high resistance to sintering and carbon deposition. However, this method uses molecular sieve products and does not mention the molecular sieve preparation method or the source of raw materials.

[0005] In summary, existing methane dry reforming catalysts still have many shortcomings in terms of support structure and active center stability, and there is an urgent need to develop a new catalyst that combines high activity, high resistance to carbon deposition, and long cycle stability. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention proposes a Ni / Ru catalyst supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals, along with its preparation method and application. This is of great significance in overcoming the shortcomings of existing technologies in terms of support structure and the stability of active centers.

[0007] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a Ni / Ru catalyst supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals. The catalyst uses a micro / mesoporous silica zeolite molecular sieve prepared from magnesium-containing natural minerals as a support and Ni and Ru as active metals.

[0008] Magnesium silicate minerals (such as sepiolite, palygorskite, talc, magnesium attapulgite, magnesium montmorillonite, etc.) have once been strong contenders for green catalyst carriers due to their natural environmental protection properties, rich pore structure, high specific surface area and thermal stability.

[0009] This invention not only utilizes magnesium-containing natural minerals as a silicon source, but more importantly, it utilizes the intrinsically present Mg element within them as an in-situ additive. This Mg element, carried by the natural mineral itself, can be uniformly integrated into the framework or distributed within the pores during the molecular sieve crystallization process, fundamentally different from traditional chemical MgO post-modification—it exhibits higher dispersion uniformity, stronger bonding with the molecular sieve framework, and a more stable Ni / Ru-Mg synergistic interface.

[0010] This invention also provides a method for preparing the above-mentioned Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals, comprising the following steps: 1) The magnesium-containing natural minerals are stirred in a water bath with the first hydrochloric acid solution, and then filtered, washed and dried in sequence to obtain the pretreated minerals; 2) The pretreated ore is mixed with the second hydrochloric acid solution, stirred at room temperature, and then subjected to a hydrothermal reaction. After cooling, the solid precipitate is washed and then dried to obtain the acid-activated ore. 3) The acid-activated mineral is mixed with sodium hydroxide solution, and then the main template agent and the secondary template agent are added. The mixture is stirred continuously to form a stable suspension. The stable suspension is subjected to hydrothermal reaction. After cooling, the solid precipitate is washed and then dried, ground and calcined for the first time to obtain micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals. 4) Ni salt, Ru salt, the micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals, and water are stirred and mixed to obtain a suspension; 5) The suspension obtained in step 4) is dried, ground, calcined a second time and reduced in sequence to obtain a Ni / Ru catalyst supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals.

[0011] Further, in step 1), the solid-liquid ratio of the magnesium-containing natural mineral and the first hydrochloric acid solution is 1g:(6~12)mL; The concentration of the first hydrochloric acid solution is 1 mol / L.

[0012] Further, in step 1), the magnesium-containing natural mineral is selected from sepiolite, palygorskite, talc, magnesium attapulgite, or magnesium montmorillonite.

[0013] Further, in step 2), the solid-liquid ratio of the pretreated ore to the second hydrochloric acid solution is 1 g: (4~8) mL; The concentration of the second hydrochloric acid solution is 3.5 mol / L; The hydrothermal reaction is carried out at a temperature of 160-180 °C for 12-24 h.

[0014] Further, in step 3), the solid-liquid ratio of the acid-activated mineral to the sodium hydroxide solution is 1g:(18~20)mL; In the stable suspension, the mass fraction of the primary template agent is 2-8%, and the mass fraction of the secondary template agent is 1-5%. The hydrothermal reaction was carried out at a temperature of 160-180 °C for 24-36 h. The first calcination temperature is 450~650 ℃, the holding time is 2~8 h, the heating rate is 5~10 ℃ / min, and the atmosphere for the first calcination is air or nitrogen.

[0015] Further, in step 3), the main template agent is selected from tetrapropylammonium hydroxide, tetrapropylammonium bromide, tetrabutylammonium hydroxide, tetramethylammonium hydroxide, ethylenediamine, or propylenediamine; The secondary template agent is selected from hexadecyltrimethylammonium bromide, dodecyltrimethylammonium bromide, or octadecyltrimethylammonium chloride.

[0016] Further, in step 4), the mass of Ni in the Ni salt is 5-20% of the mass of the micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals; The mass of Ru in the Ru salt is 0.5 to 1.5% of the mass of the micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals.

[0017] Further, in step 5), the second calcination temperature is 350~550 ℃, the holding time is 1~4 h, the heating rate is 1~3 ℃ / min, and the atmosphere of the second calcination is air or nitrogen. The reduction atmosphere is a mixture of H2 and N2, the gas flow rate is 50~150 mL / min, the reduction temperature is 400~500 ℃, the reduction time is 120~300 min, and the heating rate is 1~10 ℃ / min.

[0018] The present invention also provides an application of the above-mentioned Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals in methane dry reforming.

[0019] Compared with the prior art, the present invention has the following advantages and technical effects: (1) This invention utilizes a hydrothermal method to synthesize micro / mesoporous silica zeolite molecular sieve supports. These supports possess a composite pore structure of microporous and mesoporous materials, combining high specific surface area and high thermal stability. The microporous structure ensures structural stability while enabling shape-selective catalysis and suppressing DRM side reactions. The mesoporous structure further enhances the mass transfer capacity of the reaction gas and increases the catalytic rate. The incorporated Mg can introduce alkaline sites and enhance the adsorption and activation capacity for CO2.

[0020] (2) This invention selects natural magnesium silicate minerals as raw materials for molecular sieve preparation. These minerals are abundant and widely distributed in nature, which can not only significantly reduce the cost of obtaining raw materials and make them readily available, but also effectively reduce the energy consumption and environmental burden caused by artificial synthesis of magnesium / silicon sources. This aligns with the concept of green chemistry and sustainable development, and has significant economic value and environmental benefits.

[0021] (3) This invention introduces the auxiliary noble metal Ru into the single-metal Ni-based catalyst to construct a Ni-Ru bimetallic catalytic system, regulates the dispersion of active centers, and ultimately forms a bimetallic-micro / mesoporous SiO2 molecular sieve composite material. In a series of characterization and reaction evaluations, this type of catalyst exhibits excellent reaction performance in terms of CO2 conversion, CH4 conversion, and H2 / CO ratio, with a volume hourly space velocity (GHSV) of 39000 mL·g. -1 ·h -1 Under the specified conditions, the CH4 conversion rate and CO2 conversion rate reached 90% and 96%, respectively, and the system demonstrated significant resistance to carbon buildup and structural stability in the 40-hour stability test, providing a solid foundation for subsequent industrial scale-up and engineering integration. Attached Figure Description

[0022] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 The images show the surface morphology and elemental distribution of the micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals (i.e., the product of step S2 in Example 1) in Example 1, where (a) is a SEM image, (b) is an elemental distribution ensemble diagram, and (c) to (h) are surface elemental distribution diagrams. Detailed Implementation

[0023] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0024] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0025] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0026] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0027] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0028] An embodiment of the present invention provides a Ni / Ru catalyst supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals, wherein the micro / mesoporous silica zeolite molecular sieve prepared from magnesium-containing natural minerals is used as the support and Ni and Ru are used as active metals.

[0029] Embodiments of the present invention also provide a method for preparing the above-mentioned Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals, comprising the following steps: 1) The magnesium-containing natural minerals are stirred in a water bath with the first hydrochloric acid solution, and then filtered, washed and dried in sequence to obtain the pretreated minerals; 2) Mix the pretreated ore with the second hydrochloric acid solution, stir at room temperature, then carry out a hydrothermal reaction, cool and wash the solid precipitate, and then dry to obtain acid-activated ore; 3) Mix the acid-activated mineral with sodium hydroxide solution, then add the main template agent and the secondary template agent, and stir continuously to form a stable suspension. The stable suspension is subjected to hydrothermal reaction, and after cooling, the solid precipitate is washed. The solid precipitate is then dried, ground and calcined in sequence to obtain micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals. 4) Ni salt, Ru salt, micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals, and water are stirred and mixed to obtain a suspension; 5) The suspension obtained in step 4) is dried, ground, calcined a second time and reduced in sequence to obtain a Ni / Ru catalyst supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals.

[0030] In a preferred embodiment of the present invention, in step 1), the solid-liquid ratio of the magnesium-containing natural mineral and the first hydrochloric acid solution is 1g:(6~12)mL; The concentration of the first hydrochloric acid solution is 1 mol / L.

[0031] In a preferred embodiment of the present invention, in step 1), the magnesium-containing natural mineral is selected from sepiolite, palygorskite, talc, magnesium attapulgite, or magnesium montmorillonite.

[0032] In a preferred embodiment of the present invention, in step 1), the water bath stirring speed is 200~500 r / min, the temperature is 60~80 ℃, and the time is 10~30 min; the drying temperature is 60~90 ℃.

[0033] In a preferred embodiment of the present invention, in step 2), the solid-liquid ratio of the pretreated ore to the second hydrochloric acid solution is 1 g: (4~8) mL; The concentration of the second hydrochloric acid solution is 3.5 mol / L; The hydrothermal reaction temperature is 160~180 ℃, and the time is 12~24 h.

[0034] In a preferred embodiment of the present invention, in step 2), the stirring speed at room temperature is 200~500 r / min, and the time is 10~30 min; The drying temperature is 95~115 ℃, and the time is 2~5 h.

[0035] In a preferred embodiment of the present invention, in step 3), the solid-liquid ratio of the acid-activated mineral to the sodium hydroxide solution is 1g:(18~20)mL; In the stable suspension, the mass fraction of the primary template agent is 2-8%, and the mass fraction of the secondary template agent is 1-5%. The hydrothermal reaction temperature is 160~180 ℃, and the time is 24~36 h; The drying temperature is 95~115 ℃, and the drying time is 2~5 h; The temperature of the first calcination is 450~650 ℃, the holding time is 2~8 h, the heating rate is 5~10 ℃ / min, and the atmosphere of the first calcination is air or nitrogen.

[0036] In a preferred embodiment of the present invention, in step 3), the main template agent is selected from tetrapropylammonium hydroxide, tetrapropylammonium bromide, tetrabutylammonium hydroxide, tetramethylammonium hydroxide, ethylenediamine or propylenediamine; The secondary template agent is selected from hexadecyltrimethylammonium bromide, dodecyltrimethylammonium bromide, or octadecyltrimethylammonium chloride.

[0037] In a preferred embodiment of the present invention, in step 4), the mass of Ni in the Ni salt is 5-20% of the mass of the micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals; The mass of Ru in Ru salt is 0.5 to 1.5% of the mass of the micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals.

[0038] For example, the Ni salt is nickel nitrate hexahydrate; the Ru salt is ruthenium trichloride.

[0039] For example, in step 4), the type of water is deionized water, and the amount of water used is such that the Ni salt and Ru salt are just dissolved.

[0040] In a preferred embodiment of the present invention, in step 4), the mixing speed is 300~500 r / min, the mixing time is 480~720 min, and the mixing is carried out in a water bath at 60 ℃.

[0041] In a preferred embodiment of the present invention, in step 5), the drying temperature is 60~150 ℃ and the drying time is 8~24 h; The second calcination temperature is 350~550 ℃, the holding time is 1~4 h, the heating rate is 1~3 ℃ / min, and the atmosphere for the second calcination is air or nitrogen. The reducing atmosphere is a mixture of H2 and N2, the gas flow rate is 50~150 mL / min, the reducing temperature is 400~500℃, the reducing time is 120~300 min, and the heating rate is 1~10 ℃ / min.

[0042] Embodiments of the present invention also provide an application of the above-mentioned Ni / Ru catalyst supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals in methane dry reforming.

[0043] When the Ni / Ru catalyst supported on the micro / mesoporous silica zeolite molecular sieve of the present invention, based on magnesium-containing natural minerals, is applied to the catalysis of methane dry reforming, a mixed gas of CH4, CO2 and N2 is introduced to react with the catalyst in situ.

[0044] The mass of the Ni / Ru catalyst supported on the micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals is 100~200 mg, the flow rate of the mixed gas is 50~200 mL / min, and the flow ratio of CH4, CO2 and N2 is 1:1:(1~10). The reaction temperature is 450~900 ℃, and the reaction pressure is 0.01~0.3 MPa.

[0045] This invention proposes a Ni / Ru catalyst supported on a magnesium-containing natural mineral micro / mesoporous silica zeolite molecular sieve, its preparation method, and its application. Through the synergistic design of the magnesium-containing micro / mesoporous silica zeolite molecular sieve support and the Ni / Ru bimetallic active center, the structural and performance advantages of each component are fully utilized, solving the technical problem of easy deactivation of traditional methane dry reforming catalysts and providing technical support for their industrial application.

[0046] Unless otherwise specified, the room temperature in this invention is 25±2℃.

[0047] All raw materials used in the embodiments of the present invention were obtained through commercial purchase.

[0048] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.

[0049] The technical solution of the present invention will be further illustrated by the following embodiments.

[0050] Example 1 A method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals, comprising the following steps: S1: Sepiolite and 1 mol / L hydrochloric acid solution are mixed at a solid-liquid ratio of 1:6 (g:mL, the same below), and stirred in a water bath at 300 r / min for 20 min at 80℃. After no more bubbles are generated, the mixture is filtered, washed, and dried to obtain pretreated sepiolite.

[0051] Pretreated sepiolite was mixed with 3.5 mol / L hydrochloric acid solution at a solid-liquid ratio of 1:4 and stirred at 300 r / min for 30 min at room temperature. The mixture was then poured into a polytetrafluoroethylene-lined reactor and reacted at 160 °C for 12 h. After cooling, the solid precipitate was washed and then dried at 105 °C for 2 h to obtain acid-activated mineral.

[0052] S2: Add the acid-activated mineral to a 1 mol / L sodium hydroxide solution at a solid-liquid ratio of 1:20, then add weighed tetrapropylammonium hydroxide (TPAOH, with a mass concentration of 5% in the suspension) and ethylenediaminetetraacetic acid (EDTA, with a mass concentration of 2% in the suspension), and continue stirring until completely mixed. Then, transfer the suspension to a polytetrafluoroethylene-lined reactor and hydrothermally heat it at 180℃ for 24 hours. Take the solid material produced by hydrothermal treatment, wash, dry, and grind it. Finally, calcine it in an air stream at a rate of 8℃ / min to 550℃ for 5 hours to remove the organic template agent, and obtain a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals (i.e., a micro / mesoporous SiO2 molecular sieve support).

[0053] S3: Mix 2 mL of deionized water, 0.248 g of nickel nitrate hexahydrate, 0.013 g of ruthenium trichloride trihydrate and 1 g of micro / mesoporous SiO2 molecular sieve support, stir in a water bath at 60 ℃ for 6 h, dry in an oven at 120 ℃ for 12 h, grind, and then calcine in a muffle furnace at 450 ℃ for 2 h to obtain a Ni / Ru catalyst precursor supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals.

[0054] S4: The Ni / Ru catalyst precursor supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was loaded into the isothermal zone of the stainless steel tube of the fixed-bed reactor. The two ends of the sample were plugged with quartz wool. H2 / N2 with a gas volume ratio of 1:9 was introduced at a total gas flow rate of 100 mL / min. The temperature was increased from room temperature to 450 °C at a heating rate of 10 °C / min for reduction. The reduction time was 3 h, and the Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was obtained.

[0055] Figure 1 This is a surface morphology and elemental distribution diagram of the micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals (i.e., the product of step S2 in Example 1) in this embodiment. Figure 1 Figures (a) and (b) show that the prepared sample consists of uniformly distributed particles with consistent particle size and regular shape, indicating that the preparation process is stable and that the molecular sieve particles contain many trace elements (Mg, Na, Al, Fe) on their surface. Figure 1 Figures (c) to (h) show that in addition to the silicon-oxygen framework structure, the prepared molecular sieve material also has a large number of other elements (Mg, Al, Fe, Na) on its surface.

[0056] The catalyst prepared in this embodiment was used to conduct a dry reforming test of methane. The specific test procedure is as follows: 100 mg of Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was loaded into the isothermal zone of a fixed-bed reactor using a stainless steel tube. Both ends of the sample were plugged with quartz wool. CH4, CO2, and N2 with a flow ratio (volume ratio) of 1:1:8 were introduced at a total flow rate of 65 mL / min. Dry reforming was carried out at a temperature of 850 °C and an atmospheric pressure of 0.2 MPa.

[0057] Example 2 A method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals, comprising the following steps: S1: Mix palygorskite with 1 mol / L hydrochloric acid solution at a solid-liquid ratio of 1:8, stir in a water bath at 300 r / min for 20 min at 80℃, and filter, wash and dry after no more bubbles are generated to obtain pretreated palygorskite.

[0058] Pretreated palygorskite was mixed with 3.5 mol / L hydrochloric acid solution at a solid-liquid ratio of 1:5 and stirred at 300 r / min for 30 min at room temperature. The mixture was then poured into a polytetrafluoroethylene-lined reactor and reacted at 170 °C for 18 h. After cooling, the solid precipitate was washed and then dried at 105 °C for 2 h to obtain acid-activated mineral.

[0059] S2: Add the acid-activated mineral to a 1 mol / L sodium hydroxide solution at a solid-liquid ratio of 1:18, then add weighed tetrapropylammonium hydrobromide (TPABr, with a mass concentration of 2% in the suspension) and hexadecyltrimethylammonium bromide (CTAB, with a mass concentration of 5% in the suspension), and continue stirring until completely mixed. Then, transfer the suspension to a polytetrafluoroethylene-lined reactor and hydrothermally heat it at 160℃ for 36 hours. Take the solid material produced by hydrothermal treatment, wash, dry, and grind it. Finally, calcine it at 450℃ for 2 hours in an air stream at a rate of 5℃ / min to remove the organic template agent, and obtain a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals (i.e., a micro / mesoporous SiO2 molecular sieve support).

[0060] S3: Mix 2 mL of deionized water, 0.248 g of nickel nitrate hexahydrate, 0.013 g of ruthenium trichloride trihydrate and 1 g of micro / mesoporous SiO2 molecular sieve support, stir in a water bath at 60 ℃ for 6 h, dry in an oven at 120 ℃ for 12 h, grind, and then calcine in a muffle furnace at 450 ℃ for 2 h to obtain a Ni / Ru catalyst precursor supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals.

[0061] S4: The Ni / Ru catalyst precursor supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was loaded into the isothermal zone of the stainless steel tube of the fixed-bed reactor. The two ends of the sample were plugged with quartz wool. H2 / N2 with a gas volume ratio of 1:9 was introduced at a total gas flow rate of 100 mL / min. The temperature was increased from room temperature to 450 °C at a heating rate of 10 °C / min for reduction. The reduction time was 3 h, and the Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was obtained.

[0062] The catalyst prepared in this example was used to conduct a dry reforming test of methane. The specific test procedure was the same as in Example 1.

[0063] Example 3 A method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals, comprising the following steps: S1: Mix talc with 1 mol / L hydrochloric acid solution at a solid-liquid ratio of 1:12, stir in a water bath at 300 r / min for 20 min at 80℃, and filter, wash and dry after no more bubbles are generated to obtain pretreated talc.

[0064] Pretreated talc was mixed with 3.5 mol / L hydrochloric acid solution at a solid-liquid ratio of 1:8 and stirred at 300 r / min for 30 min at room temperature. The mixture was then poured into a polytetrafluoroethylene-lined reactor and reacted at 180 °C for 24 h. After cooling, the solid precipitate was washed and then dried at 105 °C for 2 h to obtain acid-activated mineral.

[0065] S2: Add the acid-activated ore to a 1 mol / L sodium hydroxide solution at a solid-liquid ratio of 1:20, then add weighed tetrabutylammonium hydroxide (TBAOH, with a mass concentration of 6% in the suspension) and dodecyltrimethylammonium bromide (DTAB, with a mass concentration of 5% in the suspension), and continue stirring until completely mixed. Then, transfer the suspension to a polytetrafluoroethylene-lined reactor and hydrothermally heat it at 180℃ for 36 hours. Take the solid material produced by hydrothermal treatment, wash, dry, and grind it. Finally, calcine it at 650℃ for 5 hours in an air stream at a rate of 10℃ / min to remove the organic template agent, and obtain a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals (i.e., a micro / mesoporous SiO2 molecular sieve support).

[0066] S3: Mix 2 mL of deionized water, 0.248 g of nickel nitrate hexahydrate, 0.013 g of ruthenium trichloride trihydrate and 1 g of micro / mesoporous SiO2 molecular sieve support, stir in a water bath at 60 ℃ for 6 h, dry in an oven at 120 ℃ for 12 h, grind, and then calcine in a muffle furnace at 450 ℃ for 2 h to obtain a Ni / Ru catalyst precursor supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals.

[0067] S4: The Ni / Ru catalyst precursor supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was loaded into the isothermal zone of the stainless steel tube of the fixed-bed reactor. The two ends of the sample were plugged with quartz wool. H2 / N2 with a gas volume ratio of 1:9 was introduced at a total gas flow rate of 100 mL / min. The temperature was increased from room temperature to 450 °C at a heating rate of 10 °C / min for reduction. The reduction time was 3 h, and the Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was obtained.

[0068] The catalyst prepared in this example was used to conduct a dry reforming test of methane. The specific test procedure was the same as in Example 1.

[0069] Example 4 A method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals, comprising the following steps: S1: Mix magnesium attapulgite with 1 mol / L hydrochloric acid solution at a solid-liquid ratio of 1:9, stir in a water bath at 300 r / min for 20 min at 80℃, and filter, wash and dry after no more bubbles are generated to obtain pretreated magnesium attapulgite.

[0070] Pretreated magnesium attapulgite was mixed with 3.5 mol / L hydrochloric acid solution at a solid-liquid ratio of 1:6 and stirred at 300 r / min for 30 min at room temperature. The mixture was then poured into a polytetrafluoroethylene-lined reactor and reacted at 170 °C for 24 h. After cooling, the solid precipitate was washed and then dried at 105 °C for 2 h to obtain acid-activated mineral.

[0071] S2: Add the acid-activated mineral to a 1 mol / L sodium hydroxide solution at a solid-liquid ratio of 1:18, then add weighed ethylenediamine (EDA, with a mass concentration of 8% in the suspension) and octadecyltrimethylammonium chloride (OTAC, with a mass concentration of 5% in the suspension), and continue stirring until completely mixed. Then, transfer the suspension to a polytetrafluoroethylene-lined reactor and hydrothermally heat it at 180℃ for 36 hours. Take the solid material produced by hydrothermal treatment, wash, dry, and grind it. Finally, calcine it at 650℃ for 8 hours in an air stream at a rate of 10℃ / min to remove the organic template agent, and obtain a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals (i.e., a micro / mesoporous SiO2 molecular sieve support).

[0072] S3: Mix 2 mL of deionized water, 0.248 g of nickel nitrate hexahydrate, 0.013 g of ruthenium trichloride trihydrate and 1 g of micro / mesoporous SiO2 molecular sieve support, stir in a water bath at 60 ℃ for 6 h, dry in an oven at 120 ℃ for 12 h, grind, and then calcine in a muffle furnace at 450 ℃ for 2 h to obtain a Ni / Ru catalyst precursor supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals.

[0073] S4: The Ni / Ru catalyst precursor supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was loaded into the isothermal zone of the stainless steel tube of the fixed-bed reactor. The two ends of the sample were plugged with quartz wool. H2 / N2 with a gas volume ratio of 1:9 was introduced at a total gas flow rate of 100 mL / min. The temperature was increased from room temperature to 450 °C at a heating rate of 10 °C / min for reduction. The reduction time was 3 h, and the Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was obtained.

[0074] The catalyst prepared in this example was used to conduct a dry reforming test of methane. The specific test procedure was the same as in Example 1.

[0075] Example 5 A method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals, comprising the following steps: S1: Mix magnesium montmorillonite with 1 mol / L hydrochloric acid solution at a solid-liquid ratio of 1:6, stir in a water bath at 300 r / min at 80℃ for 20 min, and filter, wash and dry after no more bubbles are generated to obtain pretreated magnesium montmorillonite.

[0076] Pretreated magnesium montmorillonite was mixed with 3.5 mol / L hydrochloric acid solution at a solid-liquid ratio of 1:4 and stirred at 300 r / min for 30 min at room temperature. The mixture was then poured into a polytetrafluoroethylene-lined reactor and reacted at 160 °C for 12 h. After cooling, the solid precipitate was washed and then dried at 105 °C for 2 h to obtain acid-activated mineral.

[0077] S2: Add the acid-activated mineral to a 1 mol / L sodium hydroxide solution at a solid-liquid ratio of 1:18, then add weighed propylenediamine (DAP, with a mass concentration of 2% in the suspension) and hexadecyltrimethylammonium bromide (CTAB, with a mass concentration of 1% in the suspension), and continue stirring until completely mixed. Then, transfer the suspension to a polytetrafluoroethylene-lined reactor and hydrothermally heat it at 170℃ for 28 hours. Take the solid material produced by hydrothermal treatment, wash, dry, and grind it. Finally, calcine it in an air stream at a rate of 8℃ / min to 550℃ for 4 hours to remove the organic template agent, and obtain a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals (i.e., a micro / mesoporous SiO2 molecular sieve support).

[0078] S3: Mix 2 mL of deionized water, 0.248 g of nickel nitrate hexahydrate, 0.013 g of ruthenium trichloride trihydrate and 1 g of micro / mesoporous SiO2 molecular sieve support, stir in a water bath at 60 ℃ for 6 h, dry in an oven at 120 ℃ for 12 h, grind, and then calcine in a muffle furnace at 450 ℃ for 2 h to obtain a Ni / Ru catalyst precursor supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals.

[0079] S4: The Ni / Ru catalyst precursor supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was loaded into the isothermal zone of the stainless steel tube of the fixed-bed reactor. The two ends of the sample were plugged with quartz wool. H2 / N2 with a gas volume ratio of 1:9 was introduced at a total gas flow rate of 100 mL / min. The temperature was increased from room temperature to 450 °C at a heating rate of 10 °C / min for reduction. The reduction time was 3 h, and the Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was obtained.

[0080] The catalyst prepared in this example was used to conduct a dry reforming test of methane. The specific test procedure was the same as in Example 1.

[0081] Example 6 A method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals, comprising the following steps: In this embodiment, steps S1 and S2 are the same as in embodiment 1.

[0082] S3: Mix 2 mL of deionized water, 0.99 g of nickel nitrate hexahydrate, 0.039 g of ruthenium trichloride trihydrate and 1 g of micro / mesoporous SiO2 molecular sieve support, stir in a water bath at 60 ℃ for 6 h, dry in an oven at 120 ℃ for 12 h, grind, and then calcine in a muffle furnace at 450 ℃ for 4 h to obtain a Ni / Ru catalyst precursor supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals.

[0083] S4: The Ni / Ru catalyst precursor supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was loaded into the isothermal zone of the stainless steel tube of the fixed-bed reactor. The two ends of the sample were plugged with quartz wool. H2 / N2 with a gas volume ratio of 1:9 was introduced at a total gas flow rate of 150 mL / min. The temperature was increased from room temperature to 450 °C at a heating rate of 10 °C / min for reduction. The reduction time was 6 h, and the Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was obtained.

[0084] The catalyst prepared in this embodiment was used to conduct a dry reforming test of methane. The specific test procedure is as follows: 200 mg of Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was loaded into the isothermal zone of a fixed-bed reactor using a stainless steel tube. Both ends of the sample were plugged with quartz wool. CH4, CO2, and N2 with a flow ratio (volume ratio) of 1:1:8 were introduced at a total flow rate of 130 mL / min. Dry reforming was carried out at a temperature of 800 °C and an atmospheric pressure of 0.1 MPa.

[0085] Example 7 A method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals, comprising the following steps: In this embodiment, steps S1 and S2 are the same as in embodiment 1.

[0086] S3: Mix 2 mL of deionized water, 0.54 g of nickel nitrate hexahydrate, 0.026 g of ruthenium trichloride trihydrate and 1 g of micro / mesoporous SiO2 molecular sieve support, stir in a water bath at 60 ℃ for 6 h, dry in an oven at 120 ℃ for 12 h, grind, and then calcine in a muffle furnace at 500 ℃ for 4 h to obtain a Ni / Ru catalyst precursor supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals.

[0087] S4: The Ni / Ru catalyst precursor supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals was loaded into the isothermal zone of the stainless steel tube of the fixed-bed reactor. The two ends of the sample were plugged with quartz wool. H2 / N2 with a gas volume ratio of 1:9 was introduced at a total gas flow rate of 150 mL / min. The temperature was increased from room temperature to 500 °C at a heating rate of 88 °C / min for 6 h to obtain the Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals.

[0088] The catalyst prepared in this embodiment was used to conduct a dry reforming test of methane. The specific test procedure was the same as in Example 6.

[0089] Comparative Example 1 A method for preparing a Ni / Ru catalyst supported on a magnesium-doped micro / mesoporous SiO2 molecular sieve, the specific steps of which are as follows: S1: Molecular sieves were prepared by chemical synthesis. 20 g of tetraethyl orthosilicate was mixed with 80 g of deionized water, and the pH was adjusted to 1.0 with 2 mol / L dilute hydrochloric acid. After stirring at 400 r / min for 20 h, 4.0 g of tetrapropylammonium hydroxide, 1.0 g of dodecyltrimethylammonium bromide, and 0.1 g of anhydrous magnesium sulfate were added, and the mixture was stirred for 20 min. The pH was adjusted to 11 with 2 mol / L NaOH solution to form a hydrogel. After stabilization, the mixture was transferred to a reaction vessel and hydrothermally heated at 180 ℃ for 24 h. The sample was removed, washed until neutral, and dried in an oven at 120 ℃ for 12 h. Then, it was calcined in a muffle furnace at 550 ℃ for 4 h with a heating rate of 2 ℃ / min to obtain magnesium-doped micro / mesoporous SiO2 molecular sieve support.

[0090] S2: Mix 2 mL of deionized water, 0.4377 g of nickel nitrate hexahydrate, 0.01 g of ruthenium trichloride trihydrate, and 1 g of magnesium-doped micro / mesoporous SiO2 molecular sieve support, stir in a water bath at 60 ℃ for 6 h, dry in an oven at 120 ℃ for 12 h, grind, and then calcine in a muffle furnace at 450 ℃ for 2 h to obtain a magnesium-doped micro / mesoporous SiO2 molecular sieve supported Ni / Ru catalyst.

[0091] The magnesium-doped micro / mesoporous SiO2 molecular sieve-supported Ni / Ru catalyst prepared in this comparative example was used to conduct methane dry reforming tests. The specific test process was the same as in Example 1.

[0092] Comparative Example 2 A method for preparing a SiO2-supported Ni / Ru catalyst includes the following steps: 2 mL of deionized water, 0.4377 g of nickel nitrate hexahydrate, 0.01 g of ruthenium trichloride trihydrate, and 1 g of SiO2 support are mixed, stirred in a water bath at 60 ℃ for 6 h, dried in an oven at 120 ℃ for 12 h, ground, and then calcined in a muffle furnace at 450 ℃ for 2 h to obtain the SiO2-supported Ni / Ru catalyst.

[0093] The SiO2-supported Ni / Ru catalyst prepared in this comparative example was used to conduct methane dry reforming tests, and the specific test process was the same as in Example 1.

[0094] Comparative Example 3 A method for preparing a MgO-supported Ni / Ru catalyst includes the following steps: 2 mL of deionized water, 0.4377 g of nickel nitrate hexahydrate, 0.01 g of ruthenium trichloride trihydrate, and 1 MgO support are mixed, stirred in a water bath at 60 °C for 6 h, dried in an oven at 120 °C for 12 h, ground, and then calcined in a muffle furnace at 450 °C for 2 h to obtain the MgO-supported Ni / Ru catalyst.

[0095] The MgO-supported Ni / Ru catalyst prepared in this comparative example was used to conduct methane dry reforming tests, and the specific test process was the same as in Example 1.

[0096] The performance test data of the above embodiments and comparative examples are shown in Table 1.

[0097] Table 1 Table 1 shows that Examples 6 and 7 increased the loading of Ru and Ni compared to Examples 1-5. Because the molecular sieve support has a large specific surface area and numerous active sites, the catalysts with increased loading exhibit stronger performance than those with lower loading. Comparative Example 1, due to the lack of abundant impurity elements, hierarchical pore structure, and surface functional groups in the chemically synthesized molecular sieve, showed inferior performance compared to the examples based on natural mineral molecular sieves. Comparative Example 2 suffered from performance degradation due to the easy sintering of SiO2. In Comparative Example 3, although MgO could inhibit carbon deposition through alkaline sites, its small specific surface area and simple pore structure failed to provide sufficient dispersion sites for the active metals, making it difficult to balance catalytic activity and stability.

[0098] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A Ni / Ru catalyst supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals, characterized in that, It uses micro / mesoporous silica zeolite molecular sieves prepared from magnesium-containing natural minerals as a carrier and Ni and Ru as active metals.

2. A method for preparing a Ni / Ru catalyst supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals as described in claim 1, characterized in that, Includes the following steps: 1) The magnesium-containing natural minerals are stirred in a water bath with the first hydrochloric acid solution, and then filtered, washed and dried in sequence to obtain the pretreated minerals; 2) The pretreated ore is mixed with the second hydrochloric acid solution, stirred at room temperature, and then subjected to a hydrothermal reaction. After cooling, the solid precipitate is washed and then dried to obtain the acid-activated ore. 3) The acid-activated mineral is mixed with sodium hydroxide solution, and then the main template agent and the secondary template agent are added. The mixture is stirred continuously to form a stable suspension. The stable suspension is subjected to hydrothermal reaction. After cooling, the solid precipitate is washed and then dried, ground and calcined for the first time to obtain micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals. 4) Ni salt, Ru salt, the micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals, and water are stirred and mixed to obtain a suspension; 5) The suspension obtained in step 4) is dried, ground, calcined a second time and reduced in sequence to obtain a Ni / Ru catalyst supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals.

3. The method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals according to claim 2, characterized in that, In step 1), the solid-liquid ratio of the magnesium-containing natural mineral and the first hydrochloric acid solution is 1 g: (6~12) mL; The concentration of the first hydrochloric acid solution is 1 mol / L.

4. The method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals according to claim 2, characterized in that, In step 1), the magnesium-containing natural mineral is selected from sepiolite, palygorskite, talc, magnesium attapulgite, or magnesium montmorillonite.

5. The method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals according to claim 2, characterized in that, In step 2), the solid-liquid ratio of the pretreated ore to the second hydrochloric acid solution is 1 g: (4~8) mL; The concentration of the second hydrochloric acid solution is 3.5 mol / L; The hydrothermal reaction is carried out at a temperature of 160-180 °C for 12-24 h.

6. The method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals according to claim 2, characterized in that, In step 3), the solid-liquid ratio of the acid-activated mineral to the sodium hydroxide solution is 1g:(18~20)mL; In the stable suspension, the mass fraction of the primary template agent is 2-8%, and the mass fraction of the secondary template agent is 1-5%. The hydrothermal reaction was carried out at a temperature of 160-180 °C for 24-36 h. The first calcination temperature is 450~650 ℃, the holding time is 2~8 h, the heating rate is 5~10 ℃ / min, and the atmosphere for the first calcination is air or nitrogen.

7. The method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals according to claim 2, characterized in that, In step 3), the main template agent is selected from tetrapropylammonium hydroxide, tetrapropylammonium bromide, tetrabutylammonium hydroxide, tetramethylammonium hydroxide, ethylenediamine, or propylenediamine; The secondary template agent is selected from hexadecyltrimethylammonium bromide, dodecyltrimethylammonium bromide, or octadecyltrimethylammonium chloride.

8. The method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals according to claim 2, characterized in that, In step 4), the mass of Ni in the Ni salt is 5-20% of the mass of the micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals; The mass of Ru in the Ru salt is 0.5 to 1.5% of the mass of the micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals.

9. The method for preparing Ni / Ru catalyst supported on micro / mesoporous silica zeolite molecular sieves based on magnesium-containing natural minerals according to claim 2, characterized in that, In step 5), the temperature of the second calcination is 350~550 ℃, the holding time is 1~4h, the heating rate is 1~3 ℃ / min, and the atmosphere of the second calcination is air; The reduction atmosphere is a mixture of H2 and N2, the gas flow rate is 50~150 mL / min, the reduction temperature is 400~500 ℃, the reduction time is 120~300 min, and the heating rate is 1~10 ℃ / min.

10. The application of the Ni / Ru catalyst supported on a micro / mesoporous silica zeolite molecular sieve based on magnesium-containing natural minerals as described in claim 1 in the dry reforming of methane.

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