Preparation method of cobalt-based Fischer-Tropsch synthesis catalyst

Abstract

The invention provides a preparation method of a cobalt-based Fischer-Tropsch synthesis catalyst, which comprises the following steps: reacting a Ti precursor with an alkaline precipitator to generate a Ti hydroxide precipitate, filtering the precipitate, and washing to obtain a Ti precipitate filter cake; the preparation method comprises the following steps: reacting a Co precursor and a Mn precursor with an alkaline precipitator to generate a Co-Mn hydroxide precipitate, filtering the precipitate, and washing to obtain a Co-Mn precipitate filter cake; mixing the precipitation filter cake of Ti and the precipitation filter cake of Co-Mn, performing extrusion molding, and performing drying and roasting to obtain Co-Mn-TiO2; and mixing a silicon source with alcohol, carrying out equivalent-volume impregnation on the Co-Mn-TiO2 catalyst, and drying and roasting to obtain the cobalt-based Fischer-Tropsch synthesis catalyst. The cobalt-based Fischer-Tropsch synthesis catalyst prepared by the method has excellent performance, high activity and high stability.

Description

Technical Field

[0001] The invention relates to the technical field of Fischer-Tropsch synthesis catalysts, and in particular to a method for preparing a cobalt-based Fischer-Tropsch synthesis catalyst. Background Art

[0002] The Fischer-Tropsch synthesis reaction refers to the synthesis gas (H 2 +CO) is converted into hydrocarbons and other chemicals under the action of a catalyst at a certain temperature and pressure. In recent years, due to the increasing shortage of petroleum resources, Fischer-Tropsch synthesis has attracted extensive attention from researchers around the world.

[0003] In the Fischer-Tropsch synthesis reaction and its process, catalyst is one of the most important core technologies. Iron (Fe), cobalt (Co), nickel (Ni), and ruthenium (Ru) are the main metal elements that can be used as active components of Fischer-Tropsch synthesis catalysts. Long-term theoretical research and practical experience have shown that Fe and Co are the two metal elements with the greatest industrial application value among the active components of catalysts. At present, the common Fischer-Tropsch synthesis catalysts in the world are mainly iron (Fe)-based catalysts and cobalt (Co)-based catalysts. Compared with iron-based Fischer-Tropsch catalysts, cobalt-based Fischer-Tropsch catalysts have the characteristics of high catalytic activity, high selectivity for straight-chain saturated heavy hydrocarbons, and low water-gas shift reaction.

[0004] Industrial cobalt-based Fischer-Tropsch synthesis catalysts, the active component cobalt is usually supported on Al 2 O 3 、SiO 2 、TiO 2 , and ZrO 2 Titanium dioxide has a high hydrothermal resistance and is also commonly used as a carrier for Fischer-Tropsch cobalt catalysts. However, due to the strong interaction between cobalt and titanium dioxide, it is still a challenge to obtain a catalyst with excellent catalytic activity and stability using titanium dioxide as a carrier catalyst.

[0005] US6130184A relates to a Fischer-Tropsch synthesis catalyst and a preparation method thereof, wherein the catalyst is Co / additive / TiO 2 The system indicates that the additive includes one or more of Mn, V, Re, Ru, Zr, Ti and Cr. Titanium dioxide is a common carrier of cobalt catalysts for Fischer-Tropsch synthesis. Due to the interaction between titanium dioxide and cobalt, it is beneficial to stability but not to catalyst activity.

[0006] Article (Li Jinlin and He Yu, etc., SiO 2 Modified TiO 2 Cobalt-based Fischer-Tropsch synthesis catalyst and its performance, Journal of South-Central University for Nationalities (Natural Science Edition), Vol. 34, No. 1) Using SiO 2Modifying the carrier titanium dioxide and then loading it to prepare a cobalt-based Fischer-Tropsch catalyst can reduce the interaction between cobalt and the carrier and improve the catalyst activity. However, the reduced interaction between cobalt and the carrier is not conducive to the stability of the catalyst. Summary of the invention

[0007] The invention provides a method for preparing a cobalt-based Fischer-Tropsch synthesis catalyst. The catalyst prepared by the method of the invention has excellent performance and has both high activity and high stability.

[0008] To achieve the purpose, the present invention provides the following technical solutions:

[0009] In one aspect of the present invention, it relates to a method for preparing a cobalt-based Fischer-Tropsch synthesis catalyst, which comprises the following steps:

[0010] 1) subjecting a Ti precursor to a precipitation reaction with an alkaline precipitant to generate a Ti hydroxide precipitate, filtering and optionally washing to obtain a Ti precipitate filter cake;

[0011] 2) subjecting the Co precursor and the Mn precursor to a precipitation reaction with an alkaline precipitant to generate a Co-Mn hydroxide precipitate, filtering and optionally washing to obtain a Co-Mn precipitate filter cake;

[0012] 3) Mixing the Ti precipitate filter cake with the Co-Mn precipitate filter cake, extruding into strips, and drying and calcining to obtain Co-Mn-TiO 2 catalyst;

[0013] 4) Mixing the silicon source with alcohol to 2 The catalyst is impregnated in equal volumes, and the cobalt-based Fischer-Tropsch synthesis catalyst is obtained through drying and calcination.

[0014] In some embodiments of the preparation method of the present invention, in step 1), the precursor of Ti is selected from one or more of titanium oxychloride, titanium tetrachloride and tetrabutyl titanate.

[0015] In some embodiments of the preparation method of the present invention, in step 1), the precipitation reaction includes the following conditions: controlling the temperature from room temperature to 80°C (e.g., 25°C, 30°C, 40°C, 50°C, 60°C, 70°C, etc.); adjusting the pH to 6.0-10.0 (e.g., 7.0, 8.0, 9.0, etc.); and / or, the aging time is 2-20h (e.g., 6h, 10h, 14h, 18h, etc.).

[0016] In some embodiments of the preparation method of the present invention, in step 2), the Co precursor is selected from one or more of cobalt nitrate, cobalt chloride, cobalt acetate and their respective hydrates.

[0017] In some embodiments of the preparation method of the present invention, in step 2), the precursor of Mn is selected from one or more of manganese nitrate, manganese chloride, manganese acetate and their respective hydrates.

[0018] In some embodiments of the preparation method of the present invention, in step 2), the precipitation reaction includes the following conditions: controlling the temperature from room temperature to 80°C (e.g., 25°C, 30°C, 40°C, 50°C, 60°C, 70°C, etc.); adjusting the pH to 6.0-10.0 (e.g., 7.0, 8.0, 9.0, etc.); and / or, the aging time is 2-20h (e.g., 6h, 10h, 14h, 18h, etc.).

[0019] In some embodiments of the preparation method of the present invention, in step 1) and step 2), the alkaline precipitant is independently selected from one or more of ammonia water, sodium hydroxide and sodium carbonate.

[0020] In some embodiments of the preparation method of the present invention, in step 1) and step 2), the precipitation reaction comprises dripping the precursor solution and the alkaline precipitant into another container in parallel.

[0021] In some embodiments of the preparation method of the present invention, in step 1) and step 2), the hydroxide precipitate is filtered and then washed until the conductivity of the washing liquid is less than 500 μs / cm.

[0022] In some embodiments of the preparation method of the present invention, in step 3), the mixing of the Ti precipitated filter cake and the Co-Mn precipitated filter cake includes kneading in a kneader, and the preferred kneading time is 10-100 min, such as 20 min, 40 min, 60 min, 80 min, etc.

[0023] In some embodiments of the preparation method of the present invention, in step 3), the extrusion molding pressure is 10-20N, such as 12N, 14N, 16N, 18N, etc.

[0024] In some embodiments of the preparation method of the present invention, in step 3), the drying temperature is 100-150°C (e.g., 110°C, 120°C, 130°C, 140°C, etc.), and the drying time is 1-10h (e.g., 2h, 4h, 6h, 8h, etc.).

[0025] In some embodiments of the preparation method of the present invention, in step 3), the calcination temperature is 350-650°C (e.g., 400°C, 450°C, 500°C, 550°C, 600°C, etc.), and the calcination time is 2-8h (e.g., 4h, 6h, etc.).

[0026] In some embodiments of the preparation method of the present invention, in step 4), the silicon source is selected from one or more of tetraethyl silicate, tetrapropyl silicate and tetrabutyl silicate.

[0027] In some embodiments of the preparation method of the present invention, in step 4), the alcohol is selected from C1-C3 small molecule alcohols, preferably one or more of ethanol, n-propanol and isopropanol, more preferably ethanol.

[0028] In some embodiments of the preparation method of the present invention, in step 4), the time for equal volume immersion is 1-10 h (eg, 2 h, 4 h, 6 h, 8 h, etc.).

[0029] In some embodiments of the preparation method of the present invention, in step 4), the drying temperature is 100-150°C (e.g., 110°C, 120°C, 130°C, 140°C, etc.), and the drying time is 1-10h (e.g., 2h, 4h, 6h, 8h, etc.).

[0030] In some embodiments of the preparation method of the present invention, in step 4), the calcination temperature is 350-650°C (e.g., 400°C, 450°C, 500°C, 550°C, 600°C, etc.), and the calcination time is 2-8h (e.g., 4h, 6h, etc.).

[0031] In another aspect of the present invention, it relates to a cobalt-based Fischer-Tropsch synthesis catalyst obtained by the above preparation method.

[0032] In some embodiments of the catalyst of the present invention, the catalyst comprises: 10-40wt% (e.g., 15wt%, 20wt%, 25wt%, 30wt%, 35wt%, etc.) of Co, 1-3wt% (e.g., 1.5wt%, 2.0wt%, 2.5wt%, etc.) of Mn, 0.3-1.5wt% (e.g., 0.5wt%, 0.7wt%, 0.9wt%, 1.1wt%, 1.3wt%, etc.) of SiO 2 , and 55.5-88.7 wt% (e.g., 60 wt%, 65 wt%, 70 wt%, 75 wt%, 80 wt%, 85 wt%, etc.) of TiO 2 .

[0033] In some embodiments of the catalyst of the present invention, TiO 2 It is composed of two crystal forms, anatase and rutile. 2 The content is greater than that of rutile TiO 2 content.

[0034] In the preparation method of the present invention, Co / auxiliary agent / TiO 2The catalyst is post-modified, rather than first modifying the titanium dioxide support and then preparing the catalyst. This method can obtain a cobalt-based Fischer-Tropsch synthesis catalyst with both high activity and high stability. DETAILED DESCRIPTION

[0035] In order to facilitate the understanding of the present invention, the present invention will be further described below in conjunction with examples. It should be understood that the following examples are only for a better understanding of the present invention and do not mean that the present invention is limited to the following examples.

[0036] Where specific experimental steps or conditions are not specified in the examples, the corresponding conventional experimental steps or conditions in the art can be used. The reagents or instruments used without specifying the manufacturer are all conventional products that can be purchased commercially.

[0037] Preparation Example

[0038] Example 1

[0039] 1) Weigh 185.2 g of titanium tetrachloride and dissolve it in 200 g of deionized water to obtain a Ti precursor solution, weigh 50 g of deionized water in a large beaker, and drop the Ti precursor solution and 1 mol / L ammonia water into the large beaker in parallel, adjust the pH value to 8.0, control the temperature to 50° C., age for 4 h, filter and wash the obtained precipitate with deionized water for multiple times until the conductivity of the washing liquid is less than 500 μs / cm, and obtain a precipitate filter cake 1.

[0040] 2) Weigh 98.8 g of cobalt nitrate hexahydrate and 6.8 g of manganese acetate and add them to 200 g of water to prepare a cobalt-manganese mixed salt solution, weigh 50 g of deionized water in a large beaker, and dropwise add the cobalt-manganese mixed salt solution and 1 mol / L ammonia water into the large beaker in parallel, adjust the pH value to 8.0, control the temperature to 60° C., age for 4 h, and wash the obtained precipitate with deionized water for multiple times until the conductivity of the washing liquid is less than 500 μs / cm, to obtain a precipitate filter cake 2.

[0041] 3) The precipitated filter cake 1 and the precipitated filter cake 2 were placed in a kneader and kneaded at room temperature for 30 minutes, extruded into strips (0.25 cm in diameter, cylindrical) at room temperature and an extrusion pressure of 12 N, dried at 120°C for 8 hours, and then calcined at 500°C for 5 hours to obtain Co / Mn / TiO 2 catalyst.

[0042] 4) Weigh 1.7 g of TEOS (tetraethyl silicate), add ethanol, and react with the Co / Mn / TiO 2 The catalyst was impregnated with equal volume for 3 h, dried at 100 °C for 8 h, and calcined at 400 °C for 3 h to obtain the modified Co / Mn / TiO 2The catalyst is referred to as catalyst 1.

[0043] XRF test results show that Catalyst 1 contains 20.1wt% Co, 1.5wt% Mn, 0.5wt% SiO 2 , 77.9wt% TiO 2 The XRD results show that the TiO 2 It is composed of two crystal forms, anatase and rutile. 2 The content is 75.0wt%, which is greater than the rutile TiO 2 (25.0wt%).

[0044] Example 2

[0045] 1) Weigh 185.2 g of titanium tetrachloride and dissolve it in 200 g of deionized water to obtain a Ti precursor solution, weigh 50 g of deionized water in a large beaker, and drop the Ti precursor solution and 1 mol / L ammonia water into the large beaker in parallel, adjust the pH value to 8.0, control the temperature to 50° C., age for 4 h, filter and wash the obtained precipitate with deionized water for multiple times until the conductivity of the washing liquid is less than 500 μs / cm, and obtain a precipitate filter cake 1.

[0046] 2) Weigh 98.8 g of cobalt nitrate hexahydrate and 6.8 g of manganese acetate and add them to 200 g of water to prepare a cobalt-manganese mixed salt solution, weigh 50 g of deionized water in a large beaker, and dropwise add the cobalt-manganese mixed salt solution and 1 mol / L ammonia water into the large beaker in parallel, adjust the pH value to 8.0, control the temperature to 60° C., age for 4 h, and wash the obtained precipitate with deionized water for multiple times until the conductivity of the washing liquid is less than 500 μs / cm, to obtain a precipitate filter cake 2.

[0047] 3) The precipitated filter cake 1 and the precipitated filter cake 2 were placed in a kneader and kneaded at room temperature for 30 minutes, extruded into strips (0.25 cm in diameter, cylindrical) at room temperature and an extrusion pressure of 12 N, dried at 120°C for 8 hours, and then calcined at 500°C for 5 hours to obtain Co / Mn / TiO 2 catalyst.

[0048] 4) Weigh 2.2 g of tetrapropyl silicate, add ethanol, and react with the Co / Mn / TiO 2 The catalyst was impregnated with equal volume for 3 h, dried at 100 °C for 8 h, and calcined at 400 °C for 3 h to obtain the modified Co / Mn / TiO 2 Catalyst, denoted as Catalyst 2.

[0049] XRF test results show that Catalyst 2 contains 20.0wt% Co, 1.5wt% Mn, 0.5wt% SiO2 , 78wt% TiO 2 The XRD results show that the TiO 2 It is composed of two crystal forms, anatase and rutile. 2 The content is 74.9wt%, which is greater than that of rutile TiO 2 (25.1wt%).

[0050] Example 3

[0051] 1) Weigh 185.2 g of titanium tetrachloride and dissolve it in 200 g of deionized water to obtain a Ti precursor solution, weigh 50 g of deionized water in a large beaker, and drop the Ti precursor solution and 1 mol / L ammonia water into the large beaker in parallel, adjust the pH value to 8.0, control the temperature to 50° C., age for 4 h, filter and wash the obtained precipitate with deionized water for multiple times until the conductivity of the washing liquid is less than 500 μs / cm, and obtain a precipitate filter cake 1.

[0052] 2) Weigh 98.8 g of cobalt nitrate hexahydrate and 6.8 g of manganese acetate and add them to 200 g of water to prepare a cobalt-manganese mixed salt solution, weigh 50 g of deionized water in a large beaker, and dropwise add the cobalt-manganese mixed salt solution and 1 mol / L ammonia water into the large beaker in parallel, adjust the pH value to 8.0, control the temperature to 60° C., age for 4 h, and wash the obtained precipitate with deionized water for multiple times until the conductivity of the washing liquid is less than 500 μs / cm, to obtain a precipitate filter cake 2.

[0053] 3) The precipitated filter cake 1 and the precipitated filter cake 2 were placed in a kneader and kneaded at room temperature for 30 minutes, extruded into strips (0.25 cm in diameter, cylindrical) at room temperature and an extrusion pressure of 12 N, dried at 120°C for 8 hours, and then calcined at 500°C for 5 hours to obtain Co / Mn / TiO 2 catalyst.

[0054] 4) Weigh 2.7 g of tetrabutyl silicate, add ethanol, and react the Co / Mn / TiO 2 The catalyst was impregnated with equal volume for 3 h, dried at 100 °C for 8 h, and calcined at 400 °C for 3 h to obtain the modified Co / Mn / TiO 2 The catalyst is recorded as catalyst 3.

[0055] XRF test results show that Catalyst 3 contains 20.1wt% Co, 1.5wt% Mn, 0.5wt% SiO 2 , 77.9wt% TiO 2 The XRD results show that the TiO 2 It is composed of two crystal forms, anatase and rutile.2 The content is 74.9wt%, which is greater than that of rutile TiO 2 (25.1wt%).

[0056] Comparative Example 1

[0057] 1) Weigh 185.2 g of titanium tetrachloride and dissolve it in 200 g of deionized water to obtain a Ti precursor solution, weigh 50 g of deionized water in a large beaker, and drop the Ti precursor solution and 1 mol / L ammonia water into the large beaker in parallel, adjust the pH value to 8.0, control the temperature to 50° C., age for 4 h, filter and wash the obtained precipitate with deionized water for multiple times until the conductivity of the washing liquid is less than 500 μs / cm, and obtain a precipitate filter cake 1.

[0058] 2) Weigh 98.8 g of cobalt nitrate hexahydrate and 6.8 g of manganese acetate and add them to 200 g of water to prepare a cobalt-manganese mixed salt solution, weigh 50 g of deionized water in a large beaker, and dropwise add the cobalt-manganese mixed salt solution and 1 mol / L ammonia water into the large beaker in parallel, adjust the pH value to 8.0, control the temperature to 60° C., age for 4 h, and wash the obtained precipitate with deionized water for multiple times until the conductivity of the washing liquid is less than 500 μs / cm, to obtain a precipitate filter cake 2.

[0059] 3) The precipitated filter cake 1 and the precipitated filter cake 2 were placed in a kneader and kneaded at room temperature for 30 minutes, extruded into strips (0.25 cm in diameter, cylindrical) at room temperature and an extrusion pressure of 12 N, dried at 120° C. for 8 hours, and then calcined at 500° C. for 5 hours to obtain contrast agent 1.

[0060] XRF test results show that Comparative Agent 1 contains 20.1wt% Co, 1.5wt% Mn, 78.4wt% TiO 2 .

[0061] Comparative Example 2

[0062] 1) Weigh 185.2 g of titanium tetrachloride and dissolve it in 200 g of deionized water to obtain a Ti precursor solution, weigh 50 g of deionized water in a large beaker, and drop the Ti precursor solution and 1 mol / L ammonia water into the large beaker in parallel, adjust the pH value to 8.0, control the temperature to 50° C., age for 4 h, filter and wash the obtained precipitate with deionized water for multiple times until the conductivity of the washing liquid is less than 500 μs / cm, and obtain a precipitate filter cake 1.

[0063] 2) The precipitated filter cake obtained in step 1 was calcined at 400°C for 3h to obtain a titanium dioxide carrier, 1.7g of TEOS (tetraethyl silicate) was weighed, ethanol was added, and an equal volume of the obtained titanium dioxide carrier was impregnated for 3h, dried at 100°C for 8h, and calcined at 400°C for 3h to obtain a modified titanium dioxide carrier.

[0064] 3) Weigh 98.8 g of cobalt nitrate hexahydrate and 6.8 g of manganese acetate and add them to 200 g of water to prepare a cobalt-manganese mixed salt solution, weigh 50 g of deionized water in a large beaker, and dropwise add the cobalt-manganese mixed salt solution and 1 mol / L ammonia water into the large beaker in parallel, adjust the pH value to 8.0, control the temperature to 60° C., age for 4 h, and wash the resulting precipitate with deionized water for multiple times until the conductivity of the washing liquid is less than 500 μs / cm to obtain a precipitate filter cake 2.

[0065] 4) The modified titanium dioxide carrier and the precipitated filter cake 2 were placed in a kneader and kneaded at room temperature for 30 minutes, extruded into strips (0.25 cm in diameter, cylindrical) at room temperature and an extrusion pressure of 12 N, dried at 120° C. for 8 hours, and then calcined at 500° C. for 5 hours to obtain contrast agent 2.

[0066] XRF test results show that contrast agent 2 contains 20.1wt% Co, 1.5wt% Mn, 0.5wt% SiO 2 , 77.9wt% TiO 2 .

[0067] Test Case

[0068] The catalytic performance of the above catalysts and comparison agents were tested.

[0069] Evaluation method: Grind the catalyst and the contrast agent to obtain particles of 20-40 mesh. Take 1 gram of the catalyst and load it into a fixed bed. 2 The reduction was carried out under the following conditions: atmosphere, air velocity 2000-8000ml / g / h, normal pressure, temperature 400℃ for 5-20h, and then the temperature was lowered to 180℃. The reducing gas was switched to the reaction gas for reaction. The reaction conditions were: the raw gas composition H 2 / CO / N 2 =66 / 33 / 1, space velocity 10000ml / g / h, pressure 2.5MPa, temperature 230°C, and measure the CO conversion rate after 10h and 110h of reaction respectively. The CO conversion rate is determined by measuring the CO content in the gas product (measured by gas chromatograph), and the calculation method of the CO conversion rate is: the number of moles of CO converted / the number of moles of CO at the inlet×100%.

[0070] The evaluation results of the catalyst and the comparative agent are shown in Table 1 below:

[0071] Table 1

[0072]

[0073] It is easy to understand that the above embodiments are only examples for clear explanation and do not mean that the present invention is limited thereto. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from this are still within the protection scope of the present invention.

Claims

1. A method for preparing a cobalt-based Fischer-Tropsch synthesis catalyst, The following steps are involved: 1) subjecting a Ti precursor to a precipitation reaction with an alkaline precipitant to generate a Ti hydroxide precipitate, filtering and optionally washing to obtain a Ti precipitate filter cake; 2) subjecting the Co precursor and the Mn precursor to a precipitation reaction with an alkaline precipitant to generate a Co-Mn hydroxide precipitate, filtering and optionally washing to obtain a Co-Mn precipitate filter cake; 3) Mixing the Ti precipitate filter cake with the Co-Mn precipitate filter cake, extruding into strips, and drying and calcining to obtain Co-Mn-TiO 2 catalyst; 4) Mixing the silicon source with alcohol to 2 The catalyst is impregnated in equal volumes, and the cobalt-based Fischer-Tropsch synthesis catalyst is obtained through drying and calcination.

2. The preparation method according to claim 1, It is characterized in that In step 1), The Ti precursor is selected from one or more of titanium oxychloride, titanium tetrachloride and tetrabutyl titanate; and / or The precipitation reaction comprises the following conditions: controlling the temperature from room temperature to 80° C.; adjusting the pH to 6.0-10.0; and / or, the aging time is 2-20 hours.

3. The preparation method according to claim 1, It is characterized in that In step 2), The Co precursor is selected from one or more of cobalt nitrate, cobalt chloride and cobalt acetate and their respective hydrates; and / or The Mn precursor is selected from one or more of manganese nitrate, manganese chloride and manganese acetate and their respective hydrates; and / or The precipitation reaction comprises the following conditions: controlling the temperature from room temperature to 80° C.; adjusting the pH to 6.0-10.0; and / or, the aging time is 2-20 hours.

4. The preparation method according to claim 1, It is characterized in that In step 1) and step 2), The alkaline precipitant is independently selected from one or more of ammonia water, sodium hydroxide and sodium carbonate; and / or The precipitation reaction comprises dripping a solution of the precursor and an alkaline precipitant into another container in parallel; and / or The hydroxide precipitate is filtered and then washed until the conductivity of the washing liquid is less than 500 μs / cm.

5. The preparation method according to claim 1, It is characterized in that In step 3), The mixing of the Ti precipitate filter cake and the Co-Mn precipitate filter cake comprises kneading in a kneader, preferably the kneading time is 10-100 min; and / or The extrusion pressure is 10-20N; and / or The drying temperature is 100-150°C and the drying time is 1-10h; and / or The calcination temperature is 350-650°C, and the calcination time is 2-8h.

6. The preparation method according to any one of claims 1 to 5, It is characterized in that In step 4), The silicon source is selected from one or more of tetraethyl silicate, tetrapropyl silicate and tetrabutyl silicate; and / or The alcohol is selected from C1-C3 small molecule alcohols, preferably one or more of ethanol, n-propanol and isopropanol, more preferably ethanol.

7. The preparation method according to claim 6, It is characterized in that In step 4), The time of equal volume immersion is 1-10 hours; and / or The drying temperature is 100-150°C and the drying time is 1-10h; and / or The calcination temperature is 350-650°C, and the calcination time is 2-8h.

8. A cobalt-based Fischer-Tropsch synthesis catalyst obtained by the preparation method according to any one of claims 1 to 7.

9. The cobalt-based Fischer-Tropsch synthesis catalyst according to claim 8, It is characterized in that The catalyst comprises: 10-40 wt% Co, 1-3 wt% Mn, 0.3-1.5 wt% SiO 2 , and 55.5-88.7wt% TiO 2 .

10. The cobalt-based Fischer-Tropsch synthesis catalyst according to claim 8, It is characterized in that TiO 2 It is composed of two crystal forms, anatase and rutile. 2 The content is greater than that of rutile TiO 2 content.

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