Catalyst systems for the direct synthesis of aromatics from carbon oxides, their preparation methods and applications

Abstract

This invention belongs to the field of chemical engineering technology, and relates to a catalyst system for the direct production of aromatics from carbon oxides, its preparation method, and its application. The catalyst system includes a silica-alumina molecular sieve and a molybdenum-based catalyst; the molybdenum-based catalyst comprises molybdenum sulfide. This invention achieves highly efficient coupling of multiple reaction steps, and has the advantages of high carbon oxide conversion rate and high selectivity for the target product, aromatics.

Description

Technical Field

[0001] This invention belongs to the field of chemical engineering technology, and relates to a catalyst system for the hydrogenation of carbon oxides (i.e., carbon monoxide and / or carbon dioxide) to produce aromatics, its preparation method and application. Background Technology

[0002] Aromatics are important chemical raw materials, and their consumption demand is increasing with the growth of the national economy. Although China's aromatics production has reached a considerable scale, the self-sufficiency rate is low, and the supply-demand imbalance remains prominent.

[0003] Syngas is one of the main intermediates in the conversion and utilization of coal resources, and related research has a history of nearly a century. Fischer-Tropsch synthesis is an important pathway for syngas conversion, and its research can be traced back to the 1920s. Under the action of catalysts containing Group VIII transition metals such as Fe, Co, Ni, and Ru, syngas can be converted into C. 2+ The distribution of hydrocarbon products is limited by Anderson-Schulz-Flory kinetics, and it is difficult to achieve significant breakthroughs in the selectivity of middle fractions.

[0004] In recent years, researchers have combined Fischer-Tropsch synthesis catalysts with acidic molecular sieves and applied them to the Fischer-Tropsch synthesis system. Utilizing the cracking activity and shape-selective effect of the molecular sieves, they have achieved improved selectivity for specific products. S. Kang et al. (Catalysis Letter, 2008, 125, 264-270 and Fuel Processing Technology, 2010, 91, 399-403) supported Fe or Fe-Cu-K on ZSM-5 molecular sieves with a Si / Al ratio of 25. Compared with bulk Fe or Fe-Cu-K catalysts, the stronger acidity of the ZSM-5 supported catalyst was beneficial to improving the C2-C4 selectivity of the products. Furthermore, the olefin / alkane ratio of the products was also improved. In addition, J. Kang et al. (Angewandte Chemie International Edition, 2011, 50, 5200-5203) used a Ru catalyst supported on a mesoporous ZSM-5 molecular sieve to improve the C5-C4 selectivity. 11 Selectivity. X. Peng (Angewandte Chemie International Edition, 2015, 54, 4553-4556) provided a design concept for Co catalysts supported on mesoporous Y zeolites. Utilizing the weaker acidity and larger pore structure of mesoporous Y zeolites (compared to ZSM-5), this supported catalyst significantly improves C selectivity. 10 -C 20The selectivity of the catalyst is also important. Besides supported catalysts, composite catalyst systems formed by mixing Fischer-Tropsch synthesis catalysts with acidic molecular sieve catalysts in different forms have also been reported extensively. J. Bao (Angewandte Chemie, 2008, 120, 359-362) encapsulated Co / Al2O3 within Hβ molecular sieves to create a core-shell structured composite catalyst; Q. Lin (Journal of Catalysis, 2016, 344, 378-388) coated Co / Pd / SiO2 with HZSM-5, increasing the C5-C content of the product. 11 Selectivity. Wang Desheng et al. (Chinese Journal of Catalysis, 2002, 23, 333-335) explored the application of Fe / MnO and ZnZSM-5 (Si / Al=25) mechanically mixed bifunctional catalysts in the direct conversion of syngas to aromatics, and obtained an aromatic selectivity of about 50%.

[0005] The above summarizes the current status of syngas-directed conversion technology based on Fischer-Tropsch synthesis. In addition, conversion based on methanol and other lower alcohols and their intermediates such as ethers is also an important approach to achieving syngas-directed conversion into chemicals. E. Javier et al. (Industrial & Engineering Chemistry Research, 1998, 37, 1211-1219) mechanically mixed Cr2O3-ZnO with HZSM-5 molecular sieve (Si / Al ratio = 154) to achieve direct gasoline production from syngas via methanol. Q. Zhang et al. (Fuel Processing Technology, 2004, 85, 1139-1150) compared the catalytic performance of composite systems of Cu-Zn, Zn-Cr, Pd / SiO2 methanol synthesis catalysts with ZSM-5, USY, and Hβ methanol conversion catalysts in syngas conversion systems. The composite catalyst system obtained by mechanically mixing Cu-Zn and USY at a 1:1 mass ratio showed superior LPG selectivity. According to reports by K. Cheng et al. (Angewandte Chemie International Edition, 2016, 55, 1-5) and F. Jiao et al. (Science, 2016, 351, 1065-1068), composite catalysts obtained by mechanically mixing ZnO-ZrO2, ZnO-Cr2O3, and SAPO-34 can directionally convert syngas into C2-C4 low-carbon olefins. Zhang Qingde et al. (Modern Chemical Industry, 2009, 29, 112-114) loaded Cu / Zn / Al2O3 and γ-Al2O3 composite catalysts / HZSM-5 (Si / Al = 38) into the first and second reaction sections of an isobaric series flow system, and controlled the reaction temperatures of the first and second stages at 270℃ and 360℃, respectively, achieving efficient conversion of syngas into aromatics. Similar two-stage process technologies have also been reported (Zhang Jing et al., Clean Coal Technology, 2013, 19, 60-67; Q. Zhang et al., Journal of Industrial and Engineering Chemistry, 2013, 19, 975-980).

[0006] To achieve the direct conversion of syngas to aromatics, the preferred technologies reported in the literature mainly include a one-step process based on Fischer-Tropsch synthesis and the shape-selective effect of acidic molecular sieves, and a two-stage process based on methanol synthesis and the shape-selective effect of acidic molecular sieves. The former faces main challenges, including difficulty in completely overcoming product distribution kinetic limitations and severe deactivation due to carbon deposition. The latter requires separate control of the process conditions for each of the two reactions, making the equipment and process more complex than the one-step process. Summary of the Invention

[0007] The technical problems to be solved by this invention are the inconvenient filling, high investment in industrial applications, low carbon-based conversion rate, low selectivity of target product aromatics, and C... 5+ To address the challenges of high non-aromatic hydrocarbon content and complex catalyst preparation, a novel catalyst system is provided. This system, when used in the hydrogenation of carbon oxides (i.e., carbon monoxide and / or carbon dioxide) to produce aromatics, exhibits advantages such as simple catalyst preparation, convenient loading, high carbon-based conversion, high selectivity for the target aromatic product, and high C2C efficiency. 5+ It has advantages such as low non-aromatic hydrocarbon content and low equipment investment cost.

[0008] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0009] The first aspect of the present invention provides a catalyst system for the direct production of aromatics from carbon oxides, the catalyst system comprising a silica-alumina molecular sieve and a molybdenum-based catalyst; the molybdenum-based catalyst comprising molybdenum sulfide.

[0010] In the above technical solution, preferably, the molybdenum-based catalyst has the general molecular formula MoX. a S b Where X is one or more of the metals Fe, Co, Ni, La, and Ce; the value of a ranges from 0 to 1; and b is the number of atoms required to satisfy the valence of each element.

[0011] In the above technical solution, preferably, the value of a is in the range of 0.1 to 0.9; more preferably, the value of a is in the range of 0.3 to 0.9.

[0012] In the above technical solution, the molybdenum-based catalyst is prepared using at least one of the following methods: oxide sulfidation, hydrothermal synthesis, and coprecipitation, with hydrothermal synthesis being preferred.

[0013] In the above technical solution, the weight ratio of the silica-alumina molecular sieve to the molybdenum-based catalyst is (0.1-10):1.

[0014] In the above technical solution, preferably, the weight ratio of the silica-alumina molecular sieve to the molybdenum-based catalyst is (0.2-4):1.

[0015] In the above technical solution, more preferably, the weight ratio of the silicon-aluminum molecular sieve to the molybdenum-based catalyst is (0.25-3):1.

[0016] In the above technical solution, the silica-alumina molecular sieve includes at least one of ZSM-5 and ZSM-11.

[0017] In the above technical solution, preferably, the silica-alumina molecular sieve includes ZSM-5 and ZSM-11; more preferably, the weight ratio of ZSM-5 and ZSM-11 is (0.25~4):1.

[0018] In the above technical solution, the Si / Al molar ratio of the silica-alumina molecular sieve is 12 to 250, preferably 12 to 80.

[0019] In the above technical solution, preferably, the silica-alumina molecular sieve is a modified molecular sieve, and the modifying element is one or more of Ag, Zn, Ga, Ni, Fe, Cu, La, and Mo. More preferably, the modifying element is at least one of Ag, Cu, and La.

[0020] In the above technical solution, the modified molecular sieve contains 0.3% to 10% modified elements by weight.

[0021] In the above technical solution, the modification method of the modified molecular sieve can be the conventional impregnation method.

[0022] The second aspect of the present invention provides that the above-mentioned catalyst system for the direct production of aromatics from carbon oxides can be prepared by conventional mechanical mixing method, that is, by mechanically mixing the molybdenum-based catalyst and the silica-alumina molecular sieve. Depending on the actual needs, it can also be made into a shaped catalyst, for example, by uniformly mixing the molybdenum-based catalyst and the silica-alumina molecular sieve and pressing it into tablets to obtain the catalyst system.

[0023] In the above technical solution, the mixing is mechanical mixing; the mixing time is 0.5 to 3 hours.

[0024] In the above technical solution, the conditions for tableting are: the pressure of the tablet press is set to 5-25 MPa.

[0025] In the above technical solution, the particle size of the catalyst system is 8 to 100 mesh.

[0026] In the above technical solution, the molybdenum-based catalyst is prepared using at least one of the following methods: oxide sulfidation, hydrothermal synthesis, and coprecipitation, with hydrothermal synthesis being preferred.

[0027] In the above technical solution, the hydrothermal synthesis method preferably includes: dissolving a molybdenum source, an optional X source, and a template agent in water to form a solution; mixing the solution with a sulfur source and then reacting it under an oxygen-free atmosphere, followed by liquid-solid separation, to obtain a solid product that is a molybdenum-based catalyst; the template agent is polyethylene glycol, preferably at least one of PEG-200, PEG-300, and PEG-400.

[0028] In the above technical solution, the sulfur source is at least one of dimethyl disulfide and carbon disulfide; preferably dimethyl disulfide.

[0029] In the above technical solution, the molybdenum source is ammonium molybdate; the X source is selected from at least one of Fe source, Co source, Ni source, La source, and Ce source; the Fe source is ferric nitrate; the Co source is cobalt acetate; the Ni source is nickel acetate; the La source is lanthanum nitrate; the Ce source is cerium nitrate; and the water is preferably deionized water.

[0030] In the above technical solution, the atomic ratio of S in the sulfur source to the metal is 5:1 to 10:1.

[0031] In the above technical solution, the concentration of molybdenum salt in the solution is 0.03 to 3 mol / L.

[0032] In the above technical solution, the mass ratio of the amount of template agent added to the mass of molybdenum atoms in the molybdenum source is 0.05:1 to 0.3:1.

[0033] In the above technical solution, the oxygen-free atmosphere is one or more of nitrogen and inert gases.

[0034] In the above technical solution, the conditions for the sealed reaction are: temperature 350-500℃, time 0.5-30 hours; the sealed reaction vessel is preferably a stainless steel high-pressure reactor.

[0035] In the above technical solution, the liquid-solid separation can be carried out using conventional separation methods, such as filtration; the obtained solid product needs to be washed and dried; the washing is preferably done with at least one of deionized water and anhydrous ethanol; the drying conditions are drying at 80-120℃ for 6-24 hours.

[0036] A third aspect of the present invention provides a method for the direct production of aromatics from carbon oxides, comprising: using carbon oxides and hydrogen as raw materials, reacting the raw materials with the above-mentioned catalyst system to obtain an aromatic-containing stream.

[0037] In the above technical solution, the carbon oxide is carbon monoxide and / or carbon dioxide.

[0038] In the above technical solution, preferably, the raw material contains 10% to 50% H2 by volume. The molar ratio of H2 to carbon oxides in the raw material is 0.25 to 1.0, preferably 0.5 to 1.0.

[0039] In the above technical solution, preferably, the reaction conditions are: reaction temperature 300–500℃, reaction pressure 0.5–10.0 MPa, and feed gas volume hourly space velocity 1000–20000 h⁻¹. -1 .

[0040] More preferably, in the above technical solution, the reaction conditions are: reaction temperature 300–400℃, reaction pressure 1.0–8.0 MPa, and feed gas volume hourly space velocity 2000–8000 h⁻¹. -1 .

[0041] In the above technical solution, the catalyst system is pretreated before the reaction. The pretreatment conditions are: reaction temperature 350–420℃, gas hourly space velocity (GHSV) 1000–3000 h⁻¹. -1 The reaction time is 2 to 24 hours, and the pretreatment atmosphere is N2, H2S / N2 (where the volume concentration of H2S is 0.1 to 10%) or dimethyl disulfide / N2 (where the volume concentration of dimethyl disulfide is 100 to 1000 ppm).

[0042] Compared with the prior art, the present invention has the following technical effects:

[0043] (1) The technical solution of the present invention, wherein the catalyst system comprises aluminosilicate molecular sieve and a molybdenum-based catalyst; the molybdenum-based catalyst comprises molybdenum sulfide. The present invention achieves efficient coupling of multi-step reactions, and through the directional secondary transformation of intermediate products, achieves highly selective generation of specific products, aromatics (aromatic selectivity can reach more than 70%).

[0044] (2) In the technical solution of the present invention, the catalyst system is prepared by using specific raw materials, namely, silica-alumina molecular sieves and molybdenum-based catalysts (including molybdenum sulfide), and by mechanical mixing to obtain the catalyst system. The preferred method for preparing the molybdenum-based catalyst is a specific hydrothermal synthesis method, using polyethylene glycol (PEG) as a template agent and dimethyl disulfide, carbon disulfide, etc., as external sulfur sources to synthesize a high-performance molybdenum sulfide-based catalyst; the technical solution of the present invention reduces C 5+ The selectivity for non-aromatic hydrocarbons improves the selectivity for the target product.

[0045] (3) The catalyst of the present invention is used in the direct production of aromatics from carbon oxides, and has the advantages of strong applicability to reactants CO and CO2, high conversion rate of carbon oxides, high selectivity of target products (aromatics), and high C... 5+ It has the advantage of low non-aromatic hydrocarbon content, and the selectivity of aromatic hydrocarbons can reach more than 70%, achieving good technical results. Detailed Implementation

[0046] In this invention, the post-reaction stream includes CO, H2, CO2, and hydrocarbon products, which consist of aromatics and C1-C2 hydrocarbons. 5+ Non-aromatic hydrocarbons. Aromatic hydrocarbons include C6-C6 hydrocarbons. 9+ Aromatics, C 5+ Non-aromatic hydrocarbons refer to aliphatic hydrocarbons with 5 or more carbon atoms. The selectivity of each product is defined as the percentage of each product's molar number in the total carbon number of the organic product. The specific calculation method is as follows:

[0047] Total carbon number of organic products = Σ(amount of substance of organic product i × number of carbon atoms in the molecule of organic product i);

[0048] Selectivity of organic product j (%) = (Amount of organic product j × Number of carbon atoms in organic product j molecule / Total number of carbon atoms in organic product) × 100%;

[0049] Aromatic selectivity (%) = C6 aromatic selectivity (%) + C7 aromatic selectivity (%) + C8 aromatic selectivity (%) + C 9+ Aromatic selectivity (%);

[0050] C 5+ Non-aromatic selectivity (%) = Σ(C k Selectivity for aliphatic hydrocarbons (%), where k is the number of carbon atoms in the aliphatic hydrocarbon, and k ≥ 5.

[0051]

Example 1

[0052] 0.04 mol of (NH4)6Mo7O 24 0.07 mol Ni(Ac)₂·4H₂O, 4 g PEG-200, and 4 g PEG-200 were dissolved in deionized water to form a homogeneous solution in 1000 mL. This solution, along with 1.0 mol dimethyl disulfide, was then sealed in a 2000 mL stainless steel autoclave under N₂ protection and maintained at 500 °C for 4 hours. The filtered solid product was washed twice with deionized water and anhydrous ethanol, and then dried at 80 °C for 24 hours to obtain MoNi. 0.25 S 2.25 It was used as a molybdenum-based catalyst.

[0053] HZSM-5 molecular sieve with a Si / Al molar ratio of 12 was used, denoted as HZ5(12); MoNi 0.25 S 2.25 HZ5(12) powder was manually ground and mixed at a mass ratio of 1:1 for 1 hour, then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0054] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 375 °C and a pressure of 3.0 MPa, with a H2 to CO molar ratio of 1:1 in the feed gas. The feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 400℃. -1 The reaction was pretreated with N2 at space velocity for 2 hours. The results of CO conversion and organic product selectivity tests after 20 hours of reaction are shown in Table 1.

[0055]

Example 1-1

[0056] At room temperature, 0.28 mol of (NH4)2MoS4 was dissolved in 500 mL of deionized water to obtain solution I. 0.07 mol of Ni(Ac)2·4H2O was dissolved in 100 mL of deionized water to obtain solution II. Solutions I and II were added dropwise to a 50 mL deionized water solution at the same rate of 25 mL / min. After solution II was added, solution I was added dropwise, and glacial acetic acid was added to adjust the pH to 7.0. After the addition was complete, the mixture was stirred at room temperature for 2 hours. The mixture was then filtered, washed with deionized water, and dried at 80 °C for 24 hours to obtain a co-precipitated precursor of Ni and Mo. This precursor was then pyrolyzed at 500 °C for 2 hours under a N2 atmosphere to obtain MoNi. 0.25 S 2.25 It was used as a molybdenum-based catalyst.

[0057] HZSM-5 molecular sieve with a Si / Al molar ratio of 12 was used, denoted as HZ5(12); MoNi 0.25 S 2.25 HZ5(12) powder was manually ground and mixed at a mass ratio of 1:1 for 1 hour, then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0058] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 375 °C and a pressure of 3.0 MPa, with a H2 to CO molar ratio of 1:1 in the feed gas. The feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 400℃. -1 The reaction was pretreated with N2 at space velocity for 2 hours. The results of CO conversion and organic product selectivity tests after 20 hours of reaction are shown in Table 1.

[0059]

Examples 1-2

[0060] 0.04 mol of (NH4)6Mo7O 24 1000 mL of a homogeneous solution was formed by dissolving 0.07 mol of Ni(Ac)₂·4H₂O and 0.07 mol of Ni(Ac)₂·4H₂O in deionized water. This solution, along with 1.0 mol of dimethyl disulfide, was then sealed in a 2000 mL stainless steel autoclave under N₂ protection and maintained at 500 °C for 4 hours. The filtered solid product was washed twice with deionized water and anhydrous ethanol, and then dried at 80 °C for 24 hours to obtain MoNi. 0.25 S 2.25 It was used as a molybdenum-based catalyst.

[0061] HZSM-5 molecular sieve with a Si / Al molar ratio of 12 was used, denoted as HZ5(12); MoNi 0.25 S2.25 HZ5(12) powder was manually ground and mixed at a mass ratio of 1:1 for 1 hour, then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0062] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 375 °C and a pressure of 3.0 MPa, with a H2 to CO molar ratio of 1:1 in the feed gas. The feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 400℃. -1 The reaction was pretreated with N2 at space velocity for 2 hours. The results of CO conversion and organic product selectivity tests after 20 hours of reaction are shown in Table 1.

[0063]

Examples 1-3

[0064] 0.04 mol of (NH4)6Mo7O 24 0.07 mol Ni(Ac)₂·4H₂O, 4 g PEG-400, and 4 g PEG-400 were dissolved in deionized water to form a homogeneous solution of 1000 mL. This solution, along with 1.0 mol dimethyl disulfide, was then sealed in a 2000 mL stainless steel autoclave under N₂ protection and maintained at 500 °C for 4 hours. The filtered solid product was washed twice with deionized water and anhydrous ethanol, and then dried at 80 °C for 24 hours to obtain MoNi. 0.25 S 2.25 It was used as a molybdenum-based catalyst.

[0065] HZSM-5 molecular sieve with a Si / Al molar ratio of 12 was used, denoted as HZ5(12); MoNi 0.25 S 2.25 HZ5(12) powder was manually ground and mixed at a mass ratio of 1:1 for 1 hour, then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0066] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 375 °C and a pressure of 3.0 MPa, with a H2 to CO molar ratio of 1:1 in the feed gas. The feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 400℃. -1 The reaction was pretreated with N2 at space velocity for 2 hours. The results of CO conversion and organic product selectivity tests after 20 hours of reaction are shown in Table 1.

[0067]

Example 2

[0068] 0.04 mol of (NH4)6Mo7O 24 ·4H₂O, 0.084 mol of lanthanum nitrate, and 4 g of PEG-300 were dissolved in deionized water to form a homogeneous solution in 1000 mL. This solution, along with 1.0 mol of dimethyl disulfide, was then sealed in a 2000 mL stainless steel autoclave under nitrogen protection and maintained at 480 °C for 6 hours. The filtered solid product was washed three times with deionized water and anhydrous ethanol, and then dried at 100 °C for 6 hours to obtain MoLa. 0.3 S 2.45 It was used as a molybdenum-based catalyst.

[0069] HZSM-5 molecular sieve with a Si / Al molar ratio of 12 was used, denoted as HZ5(12); MoLa 0.3 S 2.45 HZ5(12) powder was manually ground and mixed at a mass ratio of 1.2:1 for 0.6 hours, and then pressed into tablets and crushed under a pressure of 15MPa to obtain 40-60 mesh catalyst composition particles.

[0070] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 375 °C, a pressure of 3.0 MPa, a feed gas H2 / CO molar ratio of 1.0, and the feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 400℃. -1 The reaction was pretreated with N2 at space velocity for 2 hours. The results of CO conversion and organic product selectivity tests after 20 hours of reaction are shown in Table 1.

[0071]

Example 3

[0072] 0.04 mol of (NH4)6Mo7O 24 ·4H₂O, 0.028 mol of lanthanum nitrate, 0.028 mol of cerium nitrate, and 4 g of PEG-200 were dissolved in deionized water to form a homogeneous solution in 1000 mL. This solution, along with 1.0 mol of dimethyl disulfide, was then sealed in a 2000 mL stainless steel autoclave under N₂ protection and maintained at 480 °C for 6 hours. The filtered solid product was washed three times with deionized water and anhydrous ethanol, and then dried at 100 °C for 6 hours to obtain MoLa. 0.1 Ce 0.1 S 2.3 It was used as a molybdenum-based catalyst.

[0073] HZSM-5 molecular sieve with a Si / Al molar ratio of 12 was used, denoted as HZ5(12); MoLa 0.1 Ce 0.1 S 2.3HZ5(12) powder was mixed with mechanical stirring for 1 hour at a mass ratio of 1:1, and then pressed into tablets and crushed under a pressure of 8MPa to obtain 20-60 mesh catalyst composition particles.

[0074] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 375 °C, a pressure of 3.0 MPa, a feed gas H2 / CO molar ratio of 1.0, and the feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 400℃. -1 The reaction was pretreated with N2 at space velocity for 2 hours. The results of CO conversion and organic product selectivity tests after 20 hours of reaction are shown in Table 1.

[0075]

Example 4

[0076] 0.04 mol of (NH4)6Mo7O 24 4 H₂O and 4 g of PEG-200 were dissolved in deionized water to form a homogeneous solution in 1000 mL. This solution, along with 1.0 mol of dimethyl disulfide, was then sealed in a 2000 mL stainless steel autoclave under N₂ protection and maintained at 450 °C for 10 hours. The filtered solid product was washed three times with deionized water and anhydrous ethanol, and then dried at 120 °C for 5 hours to obtain MoS₂, which was used as a molybdenum-based catalyst.

[0077] HZSM-5 molecular sieve with a Si / Al molar ratio of 12 was used, denoted as HZ5(12); MoS2 and HZ5(12) powders were mixed at a mass ratio of 1:1 using mechanical stirring for 0.5 hours, and then pressed into tablets and crushed under a pressure of 9MPa to obtain 40-80 mesh catalyst composition particles.

[0078] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 375 °C, a pressure of 3.0 MPa, a feed gas H2 / CO molar ratio of 1.0, and the feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 400℃. -1 The reaction was pretreated with N2 at space velocity for 2 hours. The results of CO conversion and organic product selectivity tests after 20 hours of reaction are shown in Table 1.

[0079]

Example 5

[0080] Using MoLa 0.1 Ce 0.1 S 2.3(See Example 3) As a molybdenum-based catalyst, HZSM-5 molecular sieve with a Si / Al ratio of 40 was used, denoted as HZ5(40); MoLa 0.1 Ce 0.1 S 2.3 HZ5(40) powder was mixed manually for 1 hour at a mass ratio of 0.8:1, and then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0081] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 395 °C, a pressure of 2.0 MPa, a feed gas H2 / CO molar ratio of 1.0, and the feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 395 °C. -1 N2 pretreatment for 2 hours. The CO conversion rate and organic product selectivity results after 20 hours of reaction are shown in Table 1.

[0082]

Example 6

[0083] Using MoLa 0.1 Ce 0.1 S 2.3 (See Example 3) As a molybdenum-based catalyst, HZSM-5 molecular sieve with a Si / Al ratio of 60 was used, denoted as HZ5(60); MoLa 0.1 Ce 0.1 S 2.3 HZ5(60) powder was mixed by hand grinding for 1 hour at a mass ratio of 0.7:1, and then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0084] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 395 °C, a pressure of 2.0 MPa, a feed gas H2 / CO molar ratio of 1.0, and the feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 395 °C. -1 N2 pretreatment for 2 hours. The CO conversion rate and organic product selectivity results after 20 hours of reaction are shown in Table 1.

[0085]

Example 7

[0086] Using MoLa 0.1 Ce 0.1 S 2.3 (See Example 3) As a molybdenum-based catalyst, HZSM-11 molecular sieve with a Si / Al ratio of 12 was used, denoted as HZ11(12); MoLa0.1 Ce 0.1 S 2.3 HZ11(12) powder was mixed with mechanical stirring for 1 hour at a mass ratio of 1:1, and then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0087] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 395 °C, a pressure of 2.0 MPa, a feed gas H2 / CO molar ratio of 1.0, and the feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 395 °C. -1 N2 pretreatment for 2 hours. The CO conversion rate and organic product selectivity results after 20 hours of reaction are shown in Table 1.

[0088]

Example 8

[0089] Using MoLa 0.1 Ce 0.1 S 2.3 (See Example 3) As a molybdenum-based catalyst, HZSM-5 molecular sieve with a Si / Al ratio of 12 was used, denoted as HZ5(12); HZSM-11 molecular sieve with a Si / Al ratio of 12 was used, denoted as HZ11(12); MoLa 0.1 Ce 0.1 S 2.3 HZ5(12) and HZ11(12) powders were mixed in a mass ratio of 2:1:1 and mechanically stirred for 1 hour. The mixture was then pressed into tablets and crushed under a pressure of 10 MPa to obtain 20-40 mesh catalyst composition particles.

[0090] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 395 °C, a pressure of 2.0 MPa, a feed gas H2 / CO molar ratio of 1.0, and the feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 395 °C. -1 N2 pretreatment for 2 hours. The CO conversion rate and organic product selectivity results after 20 hours of reaction are shown in Table 1.

[0091]

Example 9

[0092] Using MoLa 0.1 Ce 0.1 S 2.3(See Example 3) As a molybdenum-based catalyst, HZSM-5 molecular sieve with a Si / Al ratio of 12 was used, denoted as HZ5(12); HZSM-11 molecular sieve with a Si / Al ratio of 12 was used, denoted as HZ11(12); MoLa 0.1 Ce 0.1 S 2.3 HZ5(12) and HZ11(12) powders were mixed in a mass ratio of 4:1:3 and mechanically stirred for 1 hour. The mixture was then pressed into tablets and crushed under a pressure of 10 MPa to obtain 20-40 mesh catalyst composition particles.

[0093] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 395 °C, a pressure of 2.0 MPa, a feed gas H2 / CO molar ratio of 1.0, and the feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 395 °C. -1 N2 pretreatment for 2 hours. The CO conversion rate and organic product selectivity results after 20 hours of reaction are shown in Table 1.

[0094]

Example 10

[0095] Using MoLa 0.1 Ce 0.1 S 2.3 (See Example 3) As a molybdenum-based catalyst, HZSM-5 molecular sieve with a Si / Al ratio of 12 was used, denoted as HZ5(12); HZSM-11 molecular sieve with a Si / Al ratio of 12 was used, denoted as HZ11(12); MoLa 0.1 Ce 0.1 S 2.3 HZ5(12) and HZ11(12) powders were mixed in a mass ratio of 5:4:1 and mechanically stirred for 1 hour. The mixture was then pressed into tablets and crushed under a pressure of 10 MPa to obtain 20-40 mesh catalyst composition particles.

[0096] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 395 °C, a pressure of 2.0 MPa, a feed gas H2 / CO molar ratio of 1.0, and the feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 395 °C. -1 N2 pretreatment for 2 hours. The CO conversion rate and organic product selectivity results after 20 hours of reaction are shown in Table 1.

[0097]

Example 11

[0098] Using MoLa 0.1Ce 0.1 S 2.3 (See Example 3) As a molybdenum-based catalyst, a La-modified HZSM-5 molecular sieve with a Si / Al ratio of 12 and supported on 1.5 wt% La was used, denoted as La / HZ5(12); MoLa 0.1 Ce 0.1 S 2.3 La / HZ5(12) powder was mixed with mechanical stirring for 1 hour at a mass ratio of 1:1, and then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0099] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 395 °C, a pressure of 2.0 MPa, a feed gas H2 / CO molar ratio of 1.0, and the feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 395 °C. -1 N2 pretreatment for 2 h. The catalyst was pretreated with H2 at 395℃ for 2 h before the reaction. The results of CO conversion and organic product selectivity tests after 20 hours of reaction are shown in Table 1.

[0100] Example 11-1

[0101] Using MoLa 0.1 Ce 0.1 S 2.3 (See Example 3) As a molybdenum-based catalyst, an Ag-modified HZSM-5 molecular sieve with a Si / Al ratio of 12 and supported on 4.0 wt% Ag was used, denoted as Ag / HZ5(12); MoLa 0.1 Ce 0.1 S 2.3 Ag / HZ5(12) powder was mixed with mechanical stirring for 1 hour at a mass ratio of 1:1, and then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0102] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 395 °C, a pressure of 2.0 MPa, a feed gas H2 / CO molar ratio of 1.0, and the feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 395 °C. -1 N2 pretreatment for 2 h. The catalyst was pretreated with H2 at 395℃ for 2 h before the reaction. The results of CO conversion and organic product selectivity tests after 20 hours of reaction are shown in Table 1.

[0103]

Example 11-2

[0104] Using MoLa 0.1 Ce 0.1 S 2.3 (See Example 3) As a molybdenum-based catalyst, a Cu-modified HZSM-5 molecular sieve with a Si / Al ratio of 12 and supported on 0.5 wt% La was used, denoted as Cu / HZ5(12); MoLa 0.1 Ce 0.1 S 2.3 Cu / HZ5(12) powder was mixed with mechanical stirring for 1 hour at a mass ratio of 1:1, and then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0105] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 395 °C, a pressure of 2.0 MPa, a feed gas H2 / CO molar ratio of 1.0, and the feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 395 °C. -1 N2 pretreatment for 2 h. The catalyst was pretreated with H2 at 395℃ for 2 h before the reaction. The results of CO conversion and organic product selectivity tests after 20 hours of reaction are shown in Table 1.

[0106]

Example 12

[0107] Using MoLa 0.1 Ce 0.1 S 2.3 (See Example 3) As a molybdenum-based catalyst, HZSM-5 molecular sieve with a Si / Al ratio of 12 was used, denoted as HZ5(12); MoLa 0.1 Ce 0.1 S 2.3 HZ5(12) powder was mixed with mechanical stirring for 1 hour at a mass ratio of 1:4, and then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0108] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 395 °C, a pressure of 2.0 MPa, a feed gas H2 / CO molar ratio of 1.0, and the feed gas contained 50 vol.% H2; the feed gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 395 °C. -1 N2 pretreatment for 2 hours. The CO conversion rate and organic product selectivity results after 20 hours of reaction are shown in Table 1.

[0109]

Example 13

[0110] Using MoLa0.1 Ce 0.1 S 2.3 (See Example 3) As a molybdenum-based catalyst, HZSM-5 molecular sieve with a Si / Al ratio of 12 was used, denoted as HZ5(12); MoLa 0.1 Ce 0.1 S 2.3 HZ5(12) powder was mixed with mechanical stirring for 1 hour at a mass ratio of 3:1, and then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0111] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 400 °C, a pressure of 3.0 MPa, a feed gas H2 / CO molar ratio of 1.5, and the feed gas contained 60 vol.% H2; the feed gas volume hourly space velocity was 3200 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 395 °C. -1 N2 pretreatment for 2 hours. The CO conversion rate and organic product selectivity results after 20 hours of reaction are shown in Table 1.

[0112]

Example 14

[0113] Using MoLa 0.1 Ce 0.1 S 2.3 (See Example 3) As a molybdenum-based catalyst, HZSM-5 molecular sieve with a Si / Al ratio of 12 was used, denoted as HZ5(12); MoLa 0.1 Ce 0.1 S 2.3 HZ5(12) powder was mixed with mechanical stirring for 1 hour at a mass ratio of 1:1, and then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0114] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 385 °C, a pressure of 4.0 MPa, a feed gas H2 / CO2 molar ratio of 3.0, and the feed gas contained 75 vol.% H2; the feed gas volume hourly space velocity was 4000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 395 °C. -1 N2 pretreatment for 2 hours. The CO2 conversion rate and organic product selectivity results after 20 hours of reaction are shown in Table 1.

[0115]

Example 15

[0116] Using MoLa 0.1 Ce 0.1 S 2.3(See Example 3) As a molybdenum-based catalyst, HZSM-5 molecular sieve with a Si / Al ratio of 12 was used, denoted as HZ5(12); MoLa 0.1 Ce 0.1 S 2.3 HZ5(12) powder was mixed with mechanical stirring for 1 hour at a mass ratio of 1:1, and then pressed into tablets and crushed under a pressure of 10MPa to obtain 20-40 mesh catalyst composition particles.

[0117] 1.5 g of catalyst particles were weighed and packed into the reactor. The reaction was carried out at a temperature of 395 °C and a pressure of 2.0 MPa, with a feed gas H2 / CO / CO2 molar ratio of 4 / 1 / 1, the feed gas containing 66.7 vol.% H2, and a feed gas volume hourly space velocity of 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 395 °C. -1 N2 pretreatment for 2 hours. The results of total carbon-based conversion and organic product selectivity tests after 20 hours of reaction are shown in Table 1.

[0118] Comparative Example 1

[0119] A certain amount of ammonium molybdate was weighed and added to an appropriate amount of deionized water to prepare a saturated solution. Under stirring, a 2 mol / L nitric acid solution was added, resulting in a white precipitate. The pH of the solution was adjusted to 5.0. The solution was then placed in a high-pressure reactor, which was subsequently placed in an oven at 180℃ for 24 hours. After the constant temperature period, the reactor was allowed to cool naturally. The resulting product was washed with anhydrous ethanol and deionized water, respectively. After drying, it was pyrolyzed at 500℃ for 2 hours to obtain MoO3.

[0120] HZSM-5 molecular sieve with a Si / Al ratio of 12 was used, denoted as HZ5(12); MoO3 and HZ5(12) were granulated and crushed to obtain particles of 20-40 mesh. 0.75g of MoO3 and 0.75g of HZ5(12) particles were weighed and mixed evenly. The reaction was carried out at a reaction temperature of 375℃, a pressure of 3.0MPa, a raw material gas H2 / CO molar ratio of 1.0, and the raw material contained 50 vol.% H2; the raw material gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 400℃. -1 The reaction was pretreated with N2 at space velocity for 2 hours. The results of CO conversion and organic product selectivity tests after 20 hours of reaction are shown in Table 1.

[0121] Comparative Example 2

[0122] MoNi was prepared according to the method in Example 1. 0.25 S 2.25MoNi was obtained by calcining it at 500°C for 5 hours in air. 0.25 O 3.25 HZSM-5 molecular sieve with a Si / Al ratio of 12 was used, denoted as HZ5(12); MoNi 0.25 O 3.25 HZ5(12) were granulated and crushed to obtain particles of 20-40 mesh. 0.75g of MoNi was weighed. 0.25 O 3.25 0.75g HZ5(12) particles were mixed uniformly. The reaction was carried out at a temperature of 375℃ and a pressure of 3.0MPa, with a raw material gas H2 / CO molar ratio of 1.0 and containing 50 vol.% H2; the raw material gas volume hourly space velocity was 2000 h⁻¹. -1 Catalyst evaluation was conducted under the following conditions. Before the reaction, the catalyst was subjected to 1000 h at 400℃. -1 The reaction was pretreated with N2 at space velocity for 2 hours. The results of CO conversion and organic product selectivity tests after 20 hours of reaction are shown in Table 1.

[0123] Table 1

[0124]

Claims

1. A method for direct production of aromatic hydrocarbons from carbon oxides, characterized by, Comprise: The raw material is contacted with a catalyst system to obtain an aromatic hydrocarbon-containing stream, the catalyst system comprising a silicon-aluminum molecular sieve and a molybdenum-based catalyst; The silicon-aluminum molecular sieve and the molybdenum-based catalyst are a mechanical mixture; The molecular general formula of the molybdenum-based catalyst is MoX a S b ; wherein X is one or more of Fe, Co, Ni, La, Ce metals; a is in the range of 0-1, and b is the number of atoms required to satisfy the valence of each element. The silicon-aluminum molecular sieve comprises at least one of ZSM-5 and ZSM-11.

2. The method of claim 1, wherein, In the general formula of the molybdenum-based catalyst, the value range of a is 0.1-0.

9.

3. The method of claim 1, wherein, In the general formula of the molybdenum-based catalyst, the value range of a is 0.3-0.

9.

4. The method of claim 1, wherein, The weight ratio of the silicon-aluminum molecular sieve to the molybdenum-based catalyst is (0.1-10):

1.

5. The method of claim 1, wherein, The weight ratio of the silicon-aluminum molecular sieve to the molybdenum-based catalyst is (0.25-4):

1.

6. The method of claim 1, wherein, The weight ratio of the silicon-aluminum molecular sieve to the molybdenum-based catalyst is (0.25-3):

1.

7. The method of claim 1, wherein, The silicon-aluminum molecular sieve comprises ZSM-5 and ZSM-11, and the weight ratio of ZSM-5 to ZSM-11 is (0.25-4):

1.

8. The method of claim 1, wherein, The Si / Al molar ratio of the silicon-aluminum molecular sieve is 12-250. The silicon-aluminum molecular sieve is a modified molecular sieve, and the modification element is one or more of Ag, Zn, Ga, Ni, Fe, Cu, La and Mo.

9. The method of claim 8, wherein, The Si / Al molar ratio of the silicon-aluminum molecular sieve is 12-80.

10. The method of claim 8, wherein, In the modified molecular sieve, the modification element is at least one of Ag, Cu and La.

11. The method of claim 8, wherein, The modified molecular sieve contains 0.3%-10% of the modification element by mass based on the weight of the modified molecular sieve.

12. The method of claim 8, wherein, The preparation method of the catalyst system comprises the following steps: uniformly mixing the molybdenum-based catalyst and the silicon-aluminum molecular sieve, and optionally tabletting to form the catalyst system.

13. The method of claim 12, wherein, The molybdenum-based catalyst is prepared by a hydrothermal synthesis method, which comprises the following steps: dissolving a molybdenum source, an optional X source and a template agent in water to form a solution; mixing the solution with a sulfur source and then performing a sealed reaction in an oxygen-free atmosphere, and then performing liquid-solid separation to obtain a solid product, which is the molybdenum-based catalyst; and the template agent is polyethylene glycol.

14. The method of claim 13, wherein, In the hydrothermal synthesis method of the molybdenum-based catalyst, the template agent is at least one of PEG-200, PEG-300 and PEG-400.

15. The method of claim 13, wherein, In the hydrothermal synthesis method of the molybdenum-based catalyst, the sulfur source is at least one of dimethyl disulfide and carbon disulfide. The atomic ratio of S in the sulfur source to the metal is 5:1-10:

1. The concentration of the molybdenum salt in the solution is 0.03-3 mol / L. The mass ratio of the addition amount of the template agent to the molybdenum atoms in the molybdenum source is 0.05:1-0.3:

1. The oxygen-free atmosphere is one or more of nitrogen and inert gas. The sealed reaction is performed under the following conditions: a temperature of 350-500°C and a time of 0.5-30 hours.

16. The method of claim 15, wherein, In the hydrothermal synthesis method of the molybdenum-based catalyst, the sulfur source is dimethyl disulfide.

17. The method of claim 12, wherein, In the preparation method of the catalyst system, the mixing is mechanical mixing, and the mixing time is 0.5-3 hours. The tabletting is performed under the following conditions: the pressure of the tabletting machine is set to 5-25 MPa. The particle size of the catalyst system is 8-100 mesh.

18. The method of claim 1, wherein, The carbon oxide is carbon monoxide and / or carbon dioxide.

19. The method of claim 1 wherein, The raw material contains 10% to 50% of H2 by volume; And / or, the molar ratio of H2 to carbon oxide is 0.25 to 1.0; and / or, the reaction temperature is 300 to 500 o C, the reaction pressure is 0.5 to 10.0 MPa, the volume space velocity of the raw material gas is 1000 to 20000 h -1 .

20. The method of claim 19, wherein, The molar ratio of H2 to carbon oxide is 0.5 to 1.0.

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