Fe-Ce-Pt based catalysts, their preparation methods and applications; methods for syngas-to-olefins production

Abstract

This invention relates to the field of catalyst technology, specifically to a Fe-Ce-Pt based catalyst, its preparation method and application, and a method for producing olefins from syngas. The catalyst contains the following components: A) a support; B) a component of the general formula Fe (atomic ratio). 100 A a Ce b Pt 0.01b O x The active component, wherein A is selected from at least one of Group VB, Group IVB, and Group VIB metals; a = 5-50; b = 1-10; x is the total number of oxygen atoms required to satisfy the valence of each element in the active component; and the molar ratio of Ce to Pt on the catalyst surface is 100:5-8 (elementally). When the catalyst of this invention is used in the synthesis of olefins from syngas, it features high feedstock conversion and high target product conversion.

Description

Technical Field

[0001] This invention relates to the field of catalyst technology, specifically to an Fe-Ce-Pt based catalyst, its preparation method and application, and a method for preparing olefins from syngas. Background Technology

[0002] The efficient conversion of syngas (primarily composed of CO and H2), which comes from a wide range of sources including but not limited to coal gasification, into olefins is a major route in modern coal chemical industry. This approach addresses the pollution problem associated with coal combustion and enhances my country's energy self-sufficiency (my country's energy characteristics include abundant coal, limited natural gas, and scarce oil, resulting in a strong reliance on energy imports). Syngas to olefins can be achieved through direct or indirect methods. The indirect method typically involves a route from syngas to methanol and then to lower-carbon olefins. The Fischer-Tropsch process, however, is one of the most efficient routes for synthesizing olefins from syngas in a single step.

[0003] Fischer-Tropsch synthesis refers to the process of directly synthesizing organic compounds from syngas under the action of a catalyst. It is classified into high-temperature Fischer-Tropsch (above 300℃) and low-temperature Fischer-Tropsch (200-280℃) according to the process conditions, fixed-bed Fischer-Tropsch, slurry-bed Fischer-Tropsch, and fluidized-bed Fischer-Tropsch according to the reactor type, and iron-based and cobalt-based Fischer-Tropsch according to the catalyst type. High-temperature Fischer-Tropsch generally uses a fluidized-bed process, and iron-based catalysts are commonly used. Its products are mainly low-carbon chain products with a carbon number ≤20, and are generally used to produce low-carbon olefins and gasoline / diesel. For example, patent CN1704161A mentions the preparation of an iron-based catalyst for Fischer-Tropsch synthesis, while patent CN1695804A describes a precipitated iron catalyst for fluidized-bed synthesis. Low-temperature Fischer-Tropsch synthesis often employs fixed-bed or slurry-bed processes. The catalysts used include both cobalt-based catalysts (CN110252358A mentions a cobalt catalyst and its preparation method, as well as a method for Fischer-Tropsch wax synthesis) and iron-based catalysts (CN1113905A reports the preparation of an iron catalyst for Fischer-Tropsch synthesis in a slurry-bed reactor).

[0004] There are currently some attempts to apply fixed-bed reactors to high-temperature Fischer-Tropsch synthesis for olefin production. However, because Fischer-Tropsch synthesis is a strongly exothermic reaction, heat removal within the reactor is difficult when using a fixed bed, leading to temperature runaway and catalyst deactivation. During long-term operation, CO conversion and C2 concentrations are affected. + Olefin selectivity will decrease. Fluidized beds can effectively overcome the heat release problem of fixed beds, but they still have disadvantages such as complex processes (because the catalyst needs to be reduced before the synthesis reaction, and the reduction conditions are very different from the synthesis reaction conditions, so in addition to the reactor and the subsequent separation system, there is also a reactor for reduction) and low olefin yield. Summary of the Invention

[0005] The purpose of this invention is to overcome the problems of low catalytic activity and easy deactivation of existing iron-based catalysts, and to provide a novel Fe-Ce-Pt-based catalyst, its preparation method and application, and a method for producing olefins from syngas. This catalyst, while not easily deactivated during reuse, still exhibits excellent catalytic activity.

[0006] The first aspect of this invention provides a Fe-Ce-Pt based catalyst, which contains the following components: A) a support; B) a component of the general formula Fe, in atomic ratio. 100 A a Ce b Pt 0.01b O x The active component, wherein A is selected from at least one of Group VB, Group IVB and Group VIB metal elements; a = 5-50; b = 1-10; x is the total number of oxygen atoms required to satisfy the valence of each element in the active component; and the molar ratio of Ce to Pt on the catalyst surface is 100:5-8 in terms of elements.

[0007] A second aspect of the present invention provides a method for preparing the Fe-Ce-Pt-based catalyst of the present invention, the method comprising: contacting a solution I containing Fe source and Ce source, a Pt source solution, and a solution II containing a support source and A source in the presence of an acid-base regulator to obtain a slurry, followed by drying, optionally molding, a first calcination in an oxygen-containing atmosphere I, and a second calcination in an oxygen-containing atmosphere II containing water vapor; wherein the water content in oxygen-containing atmosphere I and oxygen-containing atmosphere II is not greater than 1 ppm.

[0008] A third aspect of the present invention provides the application of the Fe-Ce-Pt based catalyst described herein in the synthesis of olefins from syngas.

[0009] A fourth aspect of the present invention provides a method for preparing olefins from syngas, the method comprising: contacting syngas with a catalyst to carry out a Fischer-Tropsch reaction.

[0010] The catalyst of the present invention, when used in the synthesis of olefins from syngas, features high feed conversion rate and high target product conversion rate, and can maintain excellent catalytic activity during long-term use. Detailed Implementation

[0011] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0012] The first aspect of this invention provides a Fe-Ce-Pt based catalyst, which contains the following components: A) a support; B) a component of the general formula Fe, in atomic ratio. 100 A a Ce b Pt 0.01b O x The active component, wherein A is selected from at least one of Group VB, Group IVB and Group VIB metal elements; a = 5-50; b = 1-10; x is the total number of oxygen atoms required to satisfy the valence of each element in the active component; and the molar ratio of Ce to Pt on the catalyst surface is 100:5-8 in terms of elements.

[0013] In this invention, the elemental analysis parameters of the catalyst surface were measured by XPS characterization.

[0014] This invention provides a novel Fe-Ce-Pt-based catalyst in which specific active components and the support work synergistically. Furthermore, the specific Ce to Pt content ratio on the catalyst surface results in excellent catalytic activity. When this catalyst is used in the synthesis of olefins from syngas, not only is CO conversion high, but C2 also exhibits high efficiency. + Olefins exhibit high selectivity, and the catalyst maintains good catalytic activity and high selectivity for C2+ olefins even during long-term operation.

[0015] In this invention, it is understood that, through the general formula Fe 100 A a Ce b Pt 0.01b O x The molar ratio of Fe, A, Ce, and Pt in the active components can be obtained as 100:a:b:0.01b, but this does not represent their actual molar content in the catalyst. For example, a = 100 / molar content of Fe in the catalyst * molar content of A in the catalyst.

[0016] In this invention, the molar ratio of Ce to Pt on the catalyst surface is detected by XPS.

[0017] According to a preferred embodiment of the present invention, a = 8-45, for example, 8, 10, 15, 20, 30, 35, 45, or any range of two of the above values. The catalyst of this embodiment exhibits better catalytic activity; when this catalyst is used in the reaction of syngas to produce olefins, C2... + Olefins exhibit high selectivity and can maintain excellent catalytic activity during long-term use.

[0018] According to a preferred embodiment of the present invention, b = 2-8, for example, 2, 3, 4, 5, 6, 7, 8, or any range of two of the above values. The catalyst of this embodiment exhibits better catalytic activity; when this catalyst is used in the reaction of syngas to produce olefins, C2... + Olefins exhibit high selectivity and can maintain excellent catalytic activity during long-term use.

[0019] According to a preferred embodiment of the present invention, A is selected from group VB metal elements, preferably at least one of V, Nb, and Ta, and more preferably V. The catalyst of this embodiment exhibits better synergistic effects among its components. When this catalyst is used in the reaction for the production of olefins from syngas, C2... + Olefins exhibit high selectivity and can maintain excellent catalytic activity during long-term use.

[0020] According to a preferred embodiment of the present invention, A is V. In this embodiment, the catalyst exhibits better synergistic effects among its components, allows for better formation of specific lattice defects, and results in improved catalytic activity. When this catalyst is used in the reaction of syngas to produce olefins, C2… + Olefins exhibit high selectivity and can maintain excellent catalytic activity during long-term use.

[0021] According to a preferred embodiment of the present invention, the support content in the catalyst is 60-80 wt% of the catalyst mass.

[0022] According to the present invention, the content of the active component in the catalyst is not particularly limited as long as the purpose of the present invention can be achieved. According to a preferred embodiment of the present invention, the content of the active component, calculated as oxide, is 20-40 wt% of the catalyst mass.

[0023] According to a preferred embodiment of the present invention, the support is selected from oxides of Si and / or Al. In this embodiment, the support and active component in the catalyst can better synergistically interact, increasing the catalyst activity and C2 efficiency during syngas-to-olefins production. + Selectivity of olefins.

[0024] In this invention, the method for preparing the Fe-Ce-Pt-based catalyst is not particularly limited as long as the purpose of this invention can be achieved. Preferably, the second aspect of this invention provides a method for preparing the Fe-Ce-Pt-based catalyst, which includes: contacting a solution I containing Fe source and Ce source, a Pt source solution, and a solution II containing support source and A source in the presence of an acid-base regulator to obtain a slurry, followed by drying, optionally molding, first calcination in an oxygen-containing atmosphere I, and second calcination in an oxygen-containing atmosphere II containing water vapor; wherein the water content in oxygen-containing atmosphere I and oxygen-containing atmosphere II is not greater than 1 ppm.

[0025] In this invention, it is understood that the water vapor contained in the oxygen-containing atmosphere II does not include the water vapor that may be present in the oxygen-containing atmosphere II.

[0026] In this invention, the preparation method of this invention can be used to prepare a specific catalyst with a Ce to Pt molar ratio of 100:5-8 on the catalyst surface, and in the specific calcination environment of the first and second calcinations of this invention, a catalyst with specific lattice defects can be formed. This catalyst exhibits high catalytic activity in the synthesis of olefins from syngas, and C2 + Olefins exhibit high selectivity, and the catalysts can maintain excellent catalytic activity during long-term use.

[0027] According to the present invention, the specific selection of oxygen-containing atmosphere I and oxygen-containing atmosphere II is not particularly limited as long as the purpose of the present invention can be achieved. According to a preferred embodiment of the present invention, oxygen-containing atmosphere I and oxygen-containing atmosphere II are each independently oxygen and / or air. Based on cost considerations, in the present invention, both oxygen-containing atmosphere I and oxygen-containing atmosphere II are selected as air, but the present invention is not limited to this.

[0028] According to a preferred embodiment of the present invention, the conditions for the first calcination include a temperature of 500-900°C, preferably 550-850°C. The catalyst obtained using this embodiment exhibits better catalytic activity, resulting in higher CO conversion and C2 conversion when used in the synthesis of olefins from syngas. + Olefins exhibit high selectivity.

[0029] According to a preferred embodiment of the present invention, the conditions for the first roasting include: a time of 0.5-5 hours, preferably 1-4 hours.

[0030] According to a preferred embodiment of the present invention, in the second calcination, the volume ratio of water vapor to oxygen-containing atmosphere II is 1-5:100, for example, 1:100, 2:100, 3:100, 4:100, 5:100, or any range of two of the above ratios. This embodiment can obtain a catalyst with specific lattice defects, exhibiting high catalytic activity. When used in syngas to olefins, it results in higher CO conversion and C2... + Olefins exhibit high selectivity.

[0031] According to a preferred embodiment of the present invention, the conditions for the second calcination include a temperature of 550-850°C, preferably 580-830°C. The catalyst obtained using this embodiment exhibits better catalytic activity, resulting in higher CO conversion and C2 conversion when used in the synthesis of olefins from syngas. + Olefins exhibit high selectivity.

[0032] According to a preferred embodiment of the present invention, the conditions for the second calcination include: a time of 0.2-2 hours, preferably 0.5-1.8 hours.

[0033] According to the present invention, as long as the purpose of the present invention can be achieved, the amount of acid-base regulator added is not particularly limited. According to a preferred embodiment of the present invention, the amount of acid-base regulator added is to adjust the pH value of the slurry to 1-5 (for example, 1, 2, 3, 4, 5, or any two of the above values).

[0034] According to the present invention, the type of acid-base regulator is not particularly limited as long as the purpose of the present invention can be achieved, as long as it can adjust the slurry to the required pH value, for example, it can be ammonia water with a concentration of 10-40wt%.

[0035] According to a preferred embodiment of the present invention, the solid content of the slurry is 15-45% by weight.

[0036] According to a preferred embodiment of the present invention, the contact conditions include a temperature of 40-80°C, and optionally the addition of water.

[0037] According to the present invention, optional water replenishment means that water may be added or not added as needed during contact. In the present invention, water may be selectively added during contact according to the solid content of the slurry.

[0038] According to the present invention, the contact is preferably dynamic, for example, by stirring and slurrying.

[0039] According to the present invention, it is understood that Solution I containing Fe source and Ce source refers to Solution I obtained by mixing raw materials such as Fe source and Ce source with corresponding good solvent. There is no special limitation on the total content of Fe source and Ce source in Solution I, as long as the Fe source and Ce source can be completely dissolved. For example, the content of Fe source and Ce source in Solution I is 0.1-1 mol / L based on Fe and Ce elements. The good solvent for dissolving Fe source and Ce source can be any solvent in the art, such as water. In specific preparation, Fe source and Ce source can be co-dissolved in water to obtain Solution I containing Fe source and Ce source.

[0040] According to the present invention, it is understood that the Pt source solution refers to a solution obtained by mixing a Pt source with a corresponding good solvent. There is no special limitation on the content of Pt source in the solution, as long as the Pt source can be completely dissolved. For example, the content of Pt source in the Pt source solution, calculated as metallic Pt, is 1-10 mg / ml. The type of good solvent is not limited, for example, water.

[0041] According to the present invention, solution II containing a carrier source and source A refers to a solution of raw materials such as a carrier source and source A with a corresponding good solvent. The method for obtaining solution II containing a carrier source and source A can be any method in the art. Preferably, the method for obtaining solution II containing a carrier source and source A includes: dissolving source A in a good solvent to obtain solution II-1, and then mixing the carrier source with solution II-1 to obtain solution II. As long as the purpose of the present invention can be achieved, the type of good solvent is not limited, and it is generally water.

[0042] In this invention, unless otherwise specified, the good solvent in Solution I, the Pt source solution, and Solution II is water.

[0043] In this invention, there is no special limitation on the amount of good solvent used in solution I, solution II and Pt source, as long as it is sufficient to dissolve the corresponding raw material source in the system; when preparing the corresponding solution, in order to enable the corresponding raw material source to dissolve more efficiently in the good solvent, it can be selected to dissolve at a certain temperature, for example, at 50-100°C.

[0044] According to a preferred embodiment of the present invention, the support source is selected from sols containing SiO2 and / or Al2O3. The catalyst obtained by this embodiment exhibits high catalytic activity and stability.

[0045] In this invention, when preparing the corresponding catalyst, there is no special limitation on the specific amounts of Fe source, Fe source, Ce source, A source, Pt source and support source. They can be selected according to the amount of active component in the corresponding catalyst, which will not be elaborated here.

[0046] In this invention, the types of Fe source, Ce source, A source, and Pt source are not limited, as long as they can provide the corresponding elements, such as chloride salts, nitrates, and inorganic ammonium salts of the corresponding elements; according to one embodiment of the invention, the Fe source is selected from at least one of Fe nitrates, citrates, chlorides, and nitrites; according to one embodiment of the invention, the Ce source is selected from at least one of Ce nitrates, citrates, and chlorides; according to one embodiment of the invention, the Pt source is selected from Pt nitrates and / or chlorides; according to one embodiment of the invention, the A source is selected from ammonium salts and / or nitrates of A.

[0047] According to the present invention, there is no particular limitation on the drying method for preparing Fe-Ce-Pt based catalysts. For example, spray drying can be performed using a spray dryer. Optionally, molding means that molding can be selected or not selected as needed. When using a spray dryer for drying, the solid substances in the slurry can be directly dried and shaped into microspheres, that is, shaped during the drying process. Subsequent re-molding can be selected or not selected as needed.

[0048] According to the present invention, only the purpose of the present invention can be achieved. There are no special limitations on the conditions for drying using a spray dryer, such as the sprayer inlet temperature being 300-350°C and / or the outlet temperature being 170-230°C.

[0049] A third aspect of the present invention provides the application of the Fe-Ce-Pt based catalyst described herein in the synthesis of olefins from syngas.

[0050] The novel Fe-Ce-Pt-based catalyst provided by this invention possesses unique properties, exhibiting high catalytic activity when used in the synthesis of olefins from syngas, resulting in high CO conversion and C2 conversion. + It exhibits olefin selectivity, and the catalyst maintains high catalytic activity even during long-term use.

[0051] A fourth aspect of the present invention provides a method for preparing olefins from syngas, the method comprising: contacting syngas with a catalyst to carry out a Fischer-Tropsch reaction.

[0052] The novel Fe-Ce-Pt-based catalyst provided by this invention possesses unique properties, enabling high CO conversion and C2P synthesis in the Fischer-Tropsch reaction of syngas to olefins. + It exhibits olefin selectivity, and the catalyst maintains high catalytic activity even during long-term use.

[0053] When the Fe-Ce-Pt-based catalyst of this invention is used in the Fischer-Tropsch reaction for the preparation of olefins from syngas, it may or may not undergo reduction before the reaction. Preferably, reduction treatment is performed first. More preferably, the reduction treatment conditions include: preferably under a H2 atmosphere, preferably at a temperature of 280-400°C, preferably at a pressure of atmospheric pressure to 8.0 MPa, and preferably at a standard volume hourly space velocity of 2000-12000 h⁻¹. -1 The preferred reduction time is 3-480 hours.

[0054] According to a preferred embodiment of the present invention, the synthesis gas includes CO and H2, preferably with a volume ratio of CO to H2 of 1:0.5-2.

[0055] According to the present invention, the conditions for the Fischer-Tropsch reaction are not particularly limited as long as the purpose of the present invention can be achieved. According to a preferred embodiment of the present invention, the conditions for the Fischer-Tropsch reaction include: a reaction temperature of 280-380°C.

[0056] According to a preferred embodiment of the present invention, the conditions for the Fischer-Tropsch reaction include a reaction pressure of 0.5-8.0 MPa.

[0057] According to a preferred embodiment of the present invention, the conditions for the Fischer-Tropsch reaction include: a standard volume hourly space velocity (SHSV) of 2000-12000 h⁻¹. -1 .

[0058] The present invention will be described in detail below through examples. In the following examples and comparative examples, the elemental analysis parameters of the catalyst surface were measured by XPS characterization method;

[0059] In the following examples and comparative examples, the water content in the air is less than 1 ppm, and the water vapor content in the atmosphere does not include water vapor that may be present in the air but is less than 1 ppm.

[0060] In this invention, C2 + Alkenes are alkenes with 2 to 20 carbon atoms, C2 + Total carbon number of olefins / Total carbon number of organic matter in the product = C2 + Total carbon number of olefins / Total carbon number of organic matter in the product + Total carbon number of CO2 in the product.

[0061] Example 1

[0062] 1) Catalyst preparation:

[0063] Dissolve 35.1g of NH4VO3 in water at 100℃ to prepare a 0.5mol / L elemental V solution I;

[0064] Take 675g of silica sol (SiO2 content is 40wt%) and mix it with solution I to obtain mixture II;

[0065] 404g of Fe(NO3)3·9H2O and 21.7g of Ce(NO3)3·6H2O were dissolved in water to prepare a 0.5mol / L mixed solution of Fe and Ce elements (III).

[0066] Mixture III and a PtCl4 solution containing 0.0005 mol of Pt element at a concentration of 5 mg / ml (calculated as metallic Pt) were added to mixture II and stirred at 48°C. At the same time, the pH of the mixture was adjusted to 5 with 25 wt% ammonia water, and the solid content of the mixture was adjusted to 35% with water to obtain slurry IV.

[0067] The slurry was spray-dried and shaped, with the inlet temperature of the sprayer being 320℃ and the outlet temperature being 190℃, to obtain the spray-dried material. The sprayed material was first calcined at 800℃ for 1 hour in an air atmosphere, and then calcined at 750℃ for 0.5 hours in an atmosphere of water vapor: air = 3:100, to obtain the catalyst.

[0068] The catalyst composition is: 30 wt% Fe 100 V 30 Ce5Pt 0.05 O x +70wt% SiO2.

[0069] XPS analysis showed that the molar ratio of Ce to Pt on the surface of the prepared catalyst was 100:6.

[0070] 2) Catalyst evaluation:

[0071] The catalyst is reduced using an in-situ reduction method. After the reduction is complete, the process conditions are switched directly to the synthesis reaction conditions in the reactor used for the reduction to start the reaction.

[0072] Reactor specifications: Millimeter fluidized bed reactor;

[0073] Catalyst loading: 50 grams;

[0074] The reduction conditions are: temperature 350℃;

[0075] Pressure 0.8MPa

[0076] Catalyst loading (standard volume hourly space velocity) 4000 hours -1 ;

[0077] Reducing gas H2;

[0078] Restoration time: 12 hours;

[0079] The synthesis reaction conditions were: reaction temperature 350℃;

[0080] Reaction pressure: 1.1 MPa;

[0081] Catalyst loading (standard volume hourly space velocity) 4000 hours -1 ;

[0082] The feedstock ratio (moles) in the synthesis gas is CO / H2 = 1:1;

[0083] After 100 hours of reaction operation, the CO conversion rate was 92%, and the C2 conversion rate was... + The selectivity for olefins (including CO2) is 63%;

[0084] When the reaction ran for 2000 hours, the CO conversion rate was 94%, and the C2 conversion rate was... + The selectivity for olefins (including CO2) is 62%.

[0085] Example 2

[0086] 1) Catalyst preparation:

[0087] Dissolve 52.7g of NH4VO3 in water at 100℃ to prepare a 0.5mol / L elemental V solution I;

[0088] Take 754g of aluminum sol (Al2O3 content 40wt%) and mix it with solution I to obtain mixture II;

[0089] 404g of Fe(NO3)3·9H2O and 34.7g of Ce(NO3)3·6H2O were dissolved in water to prepare a 0.5mol / L mixed solution of Fe and Ce elements (III).

[0090] Mixture III and a PtCl4 solution containing 0.0008 mol of Pt element at a concentration of 5 mg / ml (calculated as metallic Pt) were added to mixture II and stirred at 48°C. At the same time, the pH of the mixture was adjusted to 5 with 25 wt% ammonia water, and the solid content of the mixture was adjusted to 35% with water to obtain slurry IV.

[0091] The slurry was spray-dried and shaped, with the inlet temperature of the sprayer being 320℃ and the outlet temperature being 190℃, to obtain the spray-dried material. The sprayed material was first calcined at 850℃ for 0.8h in an air atmosphere, and then calcined at 800℃ for 0.5h in an atmosphere of water vapor: air = 2:100, to obtain the catalyst.

[0092] The catalyst composition is: 30 wt% Fe 100 V 45 Ce8Pt 0.08 O x +70wt% SiO2.

[0093] XPS analysis showed that the molar ratio of Ce to Pt on the surface of the prepared catalyst was 100:5.6.

[0094] 2) Catalyst evaluation:

[0095] The catalyst is reduced using an in-situ reduction method. After the reduction is complete, the process conditions are switched directly to the synthesis reaction conditions in the reactor used for the reduction to start the reaction.

[0096] Reactor specifications: Millimeter fluidized bed reactor;

[0097] Catalyst loading: 50 grams;

[0098] The reduction conditions are: temperature 350℃;

[0099] Pressure 0.8 MPa;

[0100] Catalyst loading (standard volume hourly space velocity) 4000 hours -1 ;

[0101] Reducing gas H2;

[0102] Restoration time: 12 hours;

[0103] The synthesis reaction conditions were: reaction temperature 350℃;

[0104] Reaction pressure: 1.1 MPa;

[0105] Catalyst loading (standard volume hourly space velocity) 4000 h⁻¹;

[0106] The feedstock ratio (moles) in the synthesis gas is CO / H2 = 1:1.

[0107] After 100 hours of reaction, the CO conversion rate was 91%, and the C2 conversion rate was... + The selectivity for olefins (including CO2) is 64%;

[0108] When the reaction ran for 2000 hours, the CO conversion rate was 93%, and the C2 conversion rate was... + The selectivity for olefins (including CO2) is 63%.

[0109] Example 3

[0110] 1) Catalyst preparation:

[0111] Dissolve 29.3g of NH4VO3 in water at 100℃ to prepare a 0.5mol / L elemental V solution I;

[0112] Take 807g of silica sol (SiO2 content 40wt%) and mix it with solution I to obtain mixture II;

[0113] 404g of Fe(NO3)3·9H2O and 13.0g of Ce(NO3)3·6H2O were dissolved in water to prepare a 0.5mol / L mixed solution of Fe and Ce elements (III).

[0114] Mixture III and a PtCl4 solution containing 0.0003 mol of Pt (calculated as metallic Pt) at 5 mg / ml were added to mixture II and stirred at 55°C. Simultaneously, the pH of the mixture was adjusted to 5 with 25 wt% ammonia. The solid content of the mixture was adjusted to 30% with water to obtain slurry IV. The slurry was then spray-dried to obtain a spray-dried material with an inlet temperature of 300°C and an outlet temperature of 175°C. The sprayed material was first calcined at 750°C for 2.5 h in air, and then calcined at 780°C for 1 h in a steam:air = 4:100 atmosphere to obtain the catalyst.

[0115] The catalyst composition is: 25wt% Fe 100 V 25 Ce3Pt 0.03 O x +75wt%SiO2.

[0116] XPS analysis showed that the molar ratio of Ce to Pt on the surface of the prepared catalyst was 100:6.4.

[0117] 2) Catalyst evaluation:

[0118] The catalyst is reduced using an in-situ reduction method. After the reduction is complete, the process conditions are switched directly to the synthesis reaction conditions in the reactor used for the reduction to start the reaction.

[0119] Reactor specifications: Millimeter fluidized bed reactor;

[0120] Catalyst loading: 50 grams;

[0121] The reduction conditions are: temperature 350℃;

[0122] Pressure 0.8 MPa;

[0123] Catalyst loading (standard volume hourly space velocity) 4000 hours - 1 ;

[0124] Reducing gas H2;

[0125] Restoration time: 12 hours;

[0126] The synthesis reaction conditions were: reaction temperature 350℃;

[0127] Reaction pressure: 1.1 MPa;

[0128] Catalyst loading (standard volume hourly space velocity) 4000 hours -1 ;

[0129] The feedstock ratio (moles) in the synthesis gas is CO / H2 = 1:1;

[0130] When the reaction ran for 100 hours, the CO conversion rate was 90%, and the C2 conversion rate was... + The selectivity for olefins (including CO2) is 62%;

[0131] When the reaction ran for 2000 hours, the CO conversion rate was 93%, and the C2 conversion rate was... + The selectivity for olefins (including CO2) is 61%.

[0132] Example 4

[0133] The catalyst was prepared and evaluated according to the method of Example 3, except that the spray-dried material was first calcined at 750°C for 2.5 h in an air atmosphere, and then calcined at 780°C for 1 h in an atmosphere of water vapor: air = 7:100. The remaining steps were the same as in Example 3, and the catalyst was finally prepared.

[0134] XPS analysis showed that the molar ratio of Ce to Pt on the surface of the prepared catalyst was 100:7.8.

[0135] When the reaction ran for 100 hours, the CO conversion rate was 89%, and the selectivity of C2+ olefins (including CO2) was 55%.

[0136] When the reaction ran for 2000 h, the CO conversion rate was 87% and the selectivity of C2+ olefins (including CO2) was 52%.

[0137] Example 5

[0138] The catalyst was prepared and evaluated according to the method of Example 3, except that 807g of titanium sol (TiO2 content 40wt%) was used instead of 807g of silica sol (SiO2 content 40wt%). The remaining steps were the same as in Example 3, and the catalyst was finally prepared.

[0139] The catalyst composition is: 25wt% Fe 100 V 25 Ce3Pt 0.03 O x +75wt% TiO2.

[0140] XPS analysis showed that the molar ratio of Ce to Pt on the surface of the prepared catalyst was 100:4.5.

[0141] After 100 hours of reaction operation, the CO conversion rate was 84%, and the C2 conversion rate was... + The selectivity for olefins (including CO2) is 59%;

[0142] When the reaction ran for 2000 hours, the CO conversion rate was 82%, and the C2 conversion rate was... + The selectivity for olefins (including CO2) is 57%.

[0143] Example 6

[0144] The catalyst was prepared and evaluated according to the method of Example 3, except that 44.2 g of (NH4)6Mo7O was used. 24 The catalyst was prepared by dissolving the element in water to prepare a 0.5 mol / L Mo elemental solution I, and the remaining steps were the same as in Example 3.

[0145] XPS analysis showed that the molar ratio of Ce to Pt on the surface of the prepared catalyst was 100:6.9.

[0146] When the reaction ran for 100 hours, the CO conversion rate was 89% and the selectivity of C2+ olefins (including CO2) was 59%.

[0147] When the reaction ran for 2000 h, the CO conversion rate was 88% and the selectivity of C2+ olefins (including CO2) was 56%.

[0148] Example 7

[0149] The catalyst was prepared and evaluated according to the method of Example 3, with the following differences: 8.2 g of NH4VO3 was dissolved in water at 100°C to prepare a 0.5 mol / L V element solution I; 778 g of silica sol (SiO2 content 40 wt%) was mixed with solution I to obtain mixture II; 404 g of Fe(NO3)3·9H2O and 43.5 g of Ce(NO3)3·6H2O were co-dissolved in water to prepare a 0.5 mol / L Fe and Ce element mixed solution III; mixture III and a 5 mg / ml PtCl4 solution containing 0.001 mol of Pt element (calculated as metallic Pt) were added to mixture II and stirred and slurryed at 55°C. The remaining steps were the same as in Example 3, and the catalyst was finally prepared.

[0150] The catalyst composition is: 25wt% Fe 100 V7Ce 10 Pt 0.1 O x +75wt% TiO2.

[0151] XPS analysis showed that the molar ratio of Ce to Pt on the surface of the prepared catalyst was 100:7.2.

[0152] After 100 hours of reaction operation, the CO conversion rate was 89%, and the C2 conversion rate was... + The selectivity for olefins (including CO2) is 59%;

[0153] When the reaction ran for 2000 hours, the CO conversion rate was 88%, and the C2 conversion rate was... + The selectivity for olefins (including CO2) is 56%.

[0154] Comparative Example 1

[0155] The catalyst was prepared and evaluated according to the method of Example 3, except that the spray-dried material was first calcined at 750°C for 2.5 h in air atmosphere, and then calcined at 780°C for 1 h in air atmosphere. The remaining steps were the same as in Example 3, and the catalyst was finally prepared.

[0156] XPS analysis showed that the molar ratio of Ce to Pt on the surface of the prepared catalyst was 100:2.

[0157] When the reaction ran for 100 hours, the CO conversion rate was 30%, and the C2 conversion rate was... + The selectivity for olefins (including CO2) is 35%.

[0158] Comparative Example 2

[0159] The catalyst was prepared and evaluated according to the method of Example 3, except that the spray-dried material was first calcined at 750°C for 2.5 h in an atmosphere of water vapor: air = 3:100, and then calcined at 780°C for 1 h in an atmosphere of water vapor: air = 4:100. The remaining steps were the same as in Example 3, and the catalyst was finally prepared.

[0160] XPS analysis showed that the molar ratio of Ce to Pt on the surface of the prepared catalyst was 100:9.

[0161] When the reaction ran for 100 hours, the CO conversion rate was 95%, and the C2 conversion rate was... + The selectivity for olefins (including CO2) is 19%.

[0162] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A Fe-Ce-Pt based catalyst, characterized in that, The catalyst contains the following components: A) Carrier; B) In terms of atomic ratio, the general formula is Fe. 100 A a Ce b Pt 0.01b O x The active components, Where A is selected from at least one metal element in group VB; a = 5-50; b = 1-10; x is the total number of oxygen atoms required to satisfy the valence of each element in the active component; On an elemental basis, the molar ratio of Ce to Pt on the catalyst surface is 100:5-8; In the catalyst, the support content is 60-80 wt% of the catalyst mass; The active component content, calculated as oxides, is 20-40 wt% of the catalyst mass.

2. The catalyst according to claim 1, wherein, a = 8-45; and / or b = 2-8; and / or A is selected from at least one of V, Nb, and Ta.

3. The catalyst according to claim 2, wherein, A is V.

4. The catalyst according to any one of claims 1-3, wherein, The support is selected from Si oxides.

5. A method for preparing the Fe-Ce-Pt based catalyst according to any one of claims 1-4, characterized in that, The preparation method includes: In the presence of an acid-base regulator, a solution I containing Fe and Ce sources, a Pt source solution, and a solution II containing a carrier source and an A source are brought into contact to obtain a slurry, which is then dried, optionally shaped, subjected to a first calcination in an oxygen-containing atmosphere I, and subjected to a second calcination in an oxygen-containing atmosphere II containing water vapor; wherein the water content in oxygen-containing atmosphere I and oxygen-containing atmosphere II is not greater than 1 ppm.

6. The preparation method according to claim 5, wherein, The conditions for the first roasting include: a temperature of 500-900℃; and / or a time of 0.5-5 hours; and / or In the second roasting, the volume ratio of water vapor to oxygen-containing atmosphere II is 1-5:100; and / or The conditions for the second roasting include: a temperature of 550-850℃; and / or a time of 0.2-2 hours; and / or The oxygen-containing atmosphere I and oxygen-containing atmosphere II are each selected from air and / or oxygen.

7. The preparation method according to claim 6, wherein, The conditions for the first roasting include: a temperature of 550-850℃; and / or a time of 1-4 hours; and / or The conditions for the second roasting include: a temperature of 580-830℃; and / or a time of 0.5-1.8h.

8. The preparation method according to claim 5, wherein, The amount of acid-base adjuster added is such that the pH of the slurry is 1-5; and / or The solid content of the slurry is 15-45% by weight; and / or The contact conditions include a temperature of 40-80°C, with water optionally added.

9. The preparation method according to claim 5, wherein, The carrier source is selected from sols containing SiO2 and / or Al2O3; and / or The Fe source is selected from at least one of Fe nitrate, citrate, chloride, and nitrite; and / or The Ce source is selected from at least one of Ce nitrate, citrate, and chloride; and / or The Pt source is selected from Pt nitrates and / or chlorides; and / or The source A is selected from the ammonium salt and / or nitrate of A.

10. The application of the Fe-Ce-Pt based catalyst according to any one of claims 1-3 in the synthesis of olefins from syngas.

11. A method for preparing olefins from syngas, characterized in that, The method includes: contacting syngas with a catalyst to carry out a Fischer-Tropsch reaction; wherein the catalyst is the catalyst according to any one of claims 1-3.

12. The preparation method according to claim 11, wherein, The synthesis gas includes CO and H2; and / or The method also includes reducing the catalyst before use; and / or The conditions for the Fischer-Tropsch reaction include: a reaction temperature of 280-380°C; and / or a reaction pressure of 0.5-8.0 MPa; and / or a standard volume hourly space velocity of 2000-12000 h⁻¹. -1 .

13. The preparation method according to claim 12, wherein, The volume ratio of CO to H2 is 1:0.5-2; and / or The reduction conditions include: under an H2 atmosphere; and / or a temperature of 280-400°C; and / or a pressure of atmospheric pressure to 8.0 MPa; and / or a standard volume hourly space velocity of 2000-12000 h⁻¹. -1 ; and / or the recovery time is 3-480 hours.