CN105289613B - Alumina load cobalt fischer-tropsch synthetic catalyst and preparation method and application - Google Patents

Abstract

An alumina-supported cobalt Fischer-Tropsch synthesis catalyst is composed of tricobalt tetroxide, silicon dioxide and alumina, and its molar composition is tricobalt tetroxide:silica:alumina=0.1-0.25:0.02-0.2:1. The catalyst of the invention has high stability and can be applied to slurry bed or fixed bed reactors.

Description

Alumina-supported cobalt Fischer-Tropsch synthesis catalyst, preparation method and application

technical field

The invention relates to a cobalt-based Fischer-Tropsch synthesis catalyst and its preparation method and application, in particular to an alumina-supported cobalt Fischer-Tropsch synthesis catalyst and its preparation method and application.

Background technique

Fischer-Tropsch synthesis reaction is the process of catalytic hydrogenation of CO to generate hydrocarbons. Its products are environmentally friendly and do not contain aromatics, sulfides, and nitrogen compounds, and have received increasing attention. Cobalt-based catalysts for Fischer-Tropsch synthesis reactions have high chain growth capabilities, are insensitive to water-gas shift reactions, are stable during the reaction process, are not prone to carbon deposition and poisoning, have fewer oxygen-containing compounds in the product, and CO conversion can be close to theoretical conversion. Rate. Cobalt-based catalysts are usually prepared by loading cobalt on alumina. However, the hydrothermal stability of alumina is poor, and it is easy to undergo hydration reaction under the hydrothermal conditions of the Fischer-Tropsch synthesis reaction, forming Al-O-Al bridges to form pseudo-thin The diaspore causes a large decrease in the specific surface area of alumina, the destruction of the pore structure, and the metals loaded on it are easy to fall off, which eventually leads to the deactivation of the catalyst.

Therefore, measures need to be taken to modify the alumina support to improve its catalytic stability as a support. The introduction of certain ions into the alumina structure can effectively remove the hydroxyl groups and anion and cation holes on the surface of alumina, and maintain its inherent pore structure and specific surface area, which is helpful for improving the hydrothermal stability of alumina and inhibiting phase transition. have a significant impact.

Contents of the invention

The purpose of the present invention is to provide a highly stable cobalt-based Fischer-Tropsch synthesis catalyst that can be used in a slurry bed or a fixed bed reactor, as well as its preparation method and application.

The present invention introduces Si element during the preparation process of the alumina precursor, and Si can combine with the hydroxyl group on the surface of the alumina precursor to form a glassy surface layer, which can form Si-O-Si or Si-O-Si or Si- The O-Al bond eliminates the surface anion holes and improves the hydrothermal stability of alumina after calcination, thereby improving the Fischer-Tropsch synthesis stability of the supported cobalt catalyst.

The catalyst of the present invention is composed of tricobalt tetroxide, silicon dioxide and alumina, and its molar composition is tricobalt tetroxide:silicon dioxide:alumina=(0.1-0.25):(0.02-0.2):1.

The preparation method of catalyst of the present invention is as follows:

(1) According to final catalyst composition, take nitric acid and be mixed with aqueous solution A, take by weighing sodium metaaluminate and be mixed with aqueous solution B, then take silicon source and be mixed with ethanol solution C, A solution volume=B solution volume+C solution volume, Wherein, nitric acid: (sodium metaaluminate+silicon source) substance ratio=(0.95-1.1): 1;

(2) First, solution A and solution B are co-precipitated in a water bath at 50-85°C, the volume flow rate of A and B is the same, and after solution B is precipitated, continue to carry out solution A and solution C in a water bath at the same temperature Co-current co-precipitation, the volume flow rate of A and C are the same;

(3) After the precipitation is completed, aging at 70-90°C for 2-24h;

(4) After aging, wash with deionized water until the sodium ion in the filtrate is less than 5ppm, then filter to obtain a filter cake, place the filter cake at 90-120°C and dry for 10-24 hours to obtain a silicon-aluminum precursor. The body is calcined at 400-800°C for 4-10 hours to obtain a silicon-containing alumina carrier;

(5) According to the final catalyst composition, take cobalt nitrate and dissolve it in water to prepare a solution, impregnate the above-mentioned silicon-containing alumina carrier in equal volume, dry at 90-120°C for 10-24h, and roast at 300-400°C for 4-10h to obtain ultimate catalyst.

The aforementioned silicon source is one of methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate, and butyl orthosilicate.

The cobalt-based catalyst for Fischer-Tropsch synthesis as described above can be reduced and reacted in a fixed-bed reactor; the reduction conditions are: 350-450°C, 0.3-1.5MPa, GHSV=300-1000h ^-1 , constant temperature 12-24h, Using hydrogen reducing gas in nitrogen, the H ₂ content is 15%-85% (v/v); the reaction conditions are: 170-230°C, 2.0-5.0Mpa, volumetric space velocity GHSV=700-2500h ^-1 , H ₂ / CO (v/v) = 2.0-2.5.

The cobalt-based catalyst for Fischer-Tropsch synthesis as described above can be reduced and reacted in a slurry bed reactor; the reduction conditions are: 270-320°C, 0.2-1.2MPa, GHSV=500-800h ^-1 , constant temperature 12-36h , using hydrogen reducing gas in nitrogen, the _H2 content is 15%-85% (v/v), the rotating speed is 400-800rpm; the reaction conditions are: 170-230°C, 2.0-3.0MPa, volumetric space velocity GHSV=700- 2000h ^-1 , H ₂ /CO(v/v) = 2.0-3.0, the rotation speed is 400-800rpm.

Compared with the existing cobalt-based catalysts for Fischer-Tropsch synthesis, the silicon-doped alumina-supported cobalt catalyst of the present invention can maintain the inherent pore structure and high specific surface area after roasting under hydrothermal reaction conditions, improve hydrothermal stability, prevent The phase transition of alumina is realized, thereby improving the stability of Fischer-Tropsch synthesis of supported cobalt catalysts.

detailed description

The following examples will further illustrate the present invention, and the protection scope of the present invention is not limited by these examples.

Example 1:

According to final catalyst composition, take by weighing 1909g 66 (wt.)% concentrated nitric acid and be mixed with 40L aqueous solution A, take by weighing 1640g sodium metaaluminate and be mixed with 32L aqueous solution B, then take by weighing 304g orthosilicate and be mixed with 8L ethanol solution C; first carry out co-current co-precipitation of solution A and solution B in a water bath at 60°C, and the volume flow rate of A and B is the same; after the precipitation of solution B is completed, continue to carry out co-current co-precipitation of solution A and solution C at 60 °C , the volume flow rate of A and C is the same; after the solution A and C are precipitated, they are aged at 80°C for 4 hours; Dry in an oven at 100°C for 10 hours to obtain a silicon-containing alumina precursor; place the obtained precursor in a muffle furnace and roast at 550°C for 6 hours to obtain a silicon-containing alumina; weigh 1746g of nitric acid hexahydrate according to the final catalyst composition Prepare an aqueous solution of cobalt, impregnate the same volume on the above carrier, dry at 65°C for 24 hours, and calcinate at 300°C for 8 hours to obtain the final catalyst, whose molar composition is cobalt tetraoxide:silicon dioxide:alumina=0.2:0.2:1.

Take 5ml of the above catalyst without dilution and fill it in a fixed bed reactor (Ф10×500mm). The reduction conditions are: 370°C, 0.5MPa, constant temperature for 12h, 1000h ^-1 (v/v), using hydrogen in nitrogen, and the _H2 content is 25% (v/v). The reaction conditions are: 230°C, 3.0MPa, 2000h ^-1 (v/v), H ₂ /CO(mol)=2.3. Evaluation results: the CO conversion rate is 41.5%, the CH ₄ selectivity is 12.3%, and the inactivation rate within 720h is 0.22%.

Take 20ml of the above catalyst for evaluation in a 1L slurry bed reactor, the reducing conditions are 320°C, 0.1MPa, 500h ^-1 (v/v), _hydrogen in nitrogen, H content of 15% (v/v), Constant temperature 12h, 600rpm. After the reduction is completed, lower the temperature to room temperature and switch to synthesis gas for reaction. The reaction conditions are 225°C, 2.0MPa, 1800h ^-1 (v/v), H ₂ /CO (v/v)=2.2, 600rpm. Evaluation results: The CO conversion rate is 46.5%, the CH ₄ selectivity is 11.2%, and the deactivation rate within 720h is 1.13%.

Example 2:

According to final catalyst composition, take by weighing 1286g 98 (wt.)% fuming nitric acid and be mixed with 20L aqueous solution A, take by weighing 1640g sodium metaaluminate and be mixed with 19L aqueous solution B, then take by weighing 208g ethyl orthosilicate and be mixed with 1L ethanol Solution C; firstly carry out co-current co-precipitation of solution A and solution B in a water bath at 70°C, the volume flow rate of A and B is the same; after the precipitation of solution B is completed, continue to co-flow co-precipitate solution A and solution C at 70 Precipitation, the volume flow rate of A and C is the same; after the precipitation of solutions A and C is completed, age at 90°C for 2 hours; after aging, wash with deionized water until the sodium ion in the filtrate is less than 5ppm, filter to obtain a filter cake, and filter the cake Place in an oven and dry at 90°C for 24 hours to obtain a silicon-containing alumina precursor; place the obtained precursor in a muffle furnace and roast at 400°C for 10 hours to obtain silicon-containing alumina; weigh 2182.5g six Prepare an aqueous solution of hydrated cobalt nitrate, impregnate an equal volume on the above-mentioned carrier, dry at 90°C for 24 hours, and calcinate at 300°C for 10 hours to obtain the final catalyst. Take 5ml of the above catalyst without dilution and fill it in a fixed bed reactor (Ф10×500mm). The reduction conditions are: 450°C, 1.5MPa, constant temperature for 15h, 300h ^-1 (v/v), using hydrogen in nitrogen, and the _H2 content is 70% (v/v), . The reaction conditions are: 220°C, 2.0MPa, 1000h ^-1 (v/v), H ₂ /CO(mol)=2.5. Evaluation results: CO conversion rate 52.6%, CH ₄ selectivity 6.9%, inactivation rate 0.03% within 720h.

Take 10ml of the above catalyst in a 1L slurry bed reactor for evaluation, the reducing conditions are 300°C, 1.2MPa, 700h ^-1 (v/v), _hydrogen in nitrogen, H content of 80% (v/v), Constant temperature 12h, 750rpm. After the reduction is completed, lower the temperature to room temperature and switch to synthesis gas for reaction. The reaction conditions are 210°C, 2.2MPa, 1500h ^-1 (v/v), H ₂ /CO (v/v)=2.2, 700rpm. Evaluation results: CO conversion rate is 60.5%, CH ₄ selectivity is 6.4%, and inactivation rate is 0.92% within 720h.

Example 3:

According to final catalyst composition, take by weighing 926.5g 68 (wt.)% concentrated nitric acid and be mixed with 20L aqueous solution A, take by weighing 620g sodium metaaluminate and be mixed with 19.5L aqueous solution B, then take by weighing 26.4g orthopropyl silicate and be mixed with 0.5L ethanol solution C; first carry out co-precipitation of solution A and solution B in a water bath at 50°C, the volume flow rate of A and B is the same; after the precipitation of solution B is completed, continue to carry out solution A and solution C at 50°C Co-precipitation, A and C have the same volume flow rate; after the precipitation of solutions A and C, age at 70°C for 24 hours; after aging, wash with deionized water until the sodium ion in the filtrate is less than 5ppm, and filter to obtain a filter cake. Dry the filter cake in an oven at 100°C for 8 hours to obtain a silicon-containing alumina precursor; place the obtained precursor in a muffle furnace and roast at 500°C for 8 hours to obtain a silicon-containing alumina; according to the final catalyst composition, weigh Prepare an aqueous solution of 873g of cobalt nitrate hexahydrate, impregnate the same volume on the above carrier, dry at 10°C for 20 hours, and roast at 320°C for 8 hours to obtain the final catalyst. The molar composition is cobalt tetraoxide: silica: alumina = 0.2:0.02:1. Take 5ml of the above catalyst without dilution and fill it in a fixed bed reactor (Ф10×500mm). The reduction conditions are: 360°C, 0.5MPa, constant temperature for 24h, 600h ^-1 (v/v), using hydrogen in nitrogen, and the _H2 content is 25% (v/v), . The reaction conditions are: 225°C, 2.5MPa, 800h ^-1 (v/v), H ₂ /CO(mol)=2.2. Evaluation results: the CO conversion rate is 75.3%, the CH ₄ selectivity is 7.7%, and the deactivation rate within 720h is 0.05%.

Take 10ml of the above catalyst for evaluation in a 1L slurry bed reactor, the reducing conditions are 340°C, 0.5MPa, 900h ^-1 (v/v), _hydrogen in nitrogen, H content of 70% (v/v), Constant temperature 18h, 720rpm. After the reduction is completed, lower the temperature to room temperature and switch to synthesis gas for reaction. The reaction conditions are 225°C, 2.8MPa, 2500h ^-1 (v/v), H ₂ /CO (v/v)=3.0, 850rpm. Evaluation results: the CO conversion rate is 49.5%, the CH ₄ selectivity is 5.0%, and the deactivation rate within 720h is 0.34%.

Example 4:

According to final catalyst composition, take by weighing 1894.7g 66.5(wt.)% concentrated nitric acid and be mixed with 30L aqueous solution A, take by weighing 1640g sodium metaaluminate and be mixed with 27.5L aqueous solution B, then take by weighing 160g orthobutyl silicate and be mixed with 2.5 L ethanol solution C; first carry out co-precipitation of solution A and solution B in a water bath at 80°C, and the volume flow rate of A and B is the same; Flow co-precipitation, the volume flow rate of A and C is the same; after the solution A and C are precipitated, age at 85°C for 4h; after aging, wash with deionized water until the sodium ion in the filtrate is less than 5ppm, filter to obtain a filter cake, and The filter cake was dried in an oven at 120°C for 12 hours to obtain a silicon-containing alumina precursor; the obtained precursor was placed in a muffle furnace and roasted at 700°C for 5 hours to obtain a silicon-containing alumina; according to the final catalyst composition, weigh 873g Prepare an aqueous solution of cobalt nitrate hexahydrate, impregnate the same volume on the above-mentioned carrier, dry at 95°C for 18 hours, and calcinate at 340°C for 6 hours to obtain the final catalyst. Take 5ml of the above catalyst without dilution and fill it in a fixed bed reactor (Ф10×500mm). The reduction conditions are: 310°C, 0.3MPa, constant temperature for 18h, 600h ^-1 (v/v), using hydrogen in nitrogen, and the _H2 content is 30% (v/v), . The reaction conditions are: 215°C, 5.0MPa, 2000h ^-1 (v/v), H ₂ /CO(mol)=2.0. Evaluation results: The CO conversion rate is 71.3%, the CH ₄ selectivity is 9.6%, and the inactivation rate within 720h is 0.21%.

Take 10ml of the above catalyst in a 1L slurry bed reactor for evaluation, the reduction conditions are 350°C, 0.1MPa, 1000h ^-1 (v/v), _hydrogen in nitrogen, H content of 60% (v/v), Constant temperature 36h, 600rpm. After the reduction, lower the temperature to room temperature and switch to syngas for reaction. The reaction conditions are 190°C, 3.0MPa, 1300h ^-1 (v/v), H ₂ /CO (v/v)=2.0, 700rpm. Evaluation results: CO conversion rate 72.8%, CH ₄ selectivity 5.8%, inactivation rate 0.22% within 720h.

Example 5:

According to final catalyst composition, take by weighing 1928.6g 98 (wt.)% fuming nitric acid and be mixed with 80L aqueous solution A, take by weighing 2460g sodium metaaluminate and be mixed with 75L aqueous solution B, then weigh 342.5g methyl orthosilicate and be mixed with 8L ethanol solution C; first carry out co-precipitation of solution A and solution B in a water bath at 80°C, and the volume flow rate of A and B is the same; Flow co-precipitation, the volume flow rate of A and C is the same; after the precipitation of solutions A and C, aging at 85°C for 6h; after aging, wash with deionized water until the sodium ion in the filtrate is less than 5ppm, filter to obtain a filter cake, and The filter cake was dried in an oven at 120°C for 10 hours to obtain a silicon-containing alumina precursor; the obtained precursor was placed in a muffle furnace and roasted at 750°C for 5 hours to obtain a silicon-containing alumina; according to the final catalyst composition, weigh 3273.8 Prepare an aqueous solution with g cobalt nitrate hexahydrate, impregnate the same volume on the above-mentioned carrier, dry at 100°C for 16 hours, and calcinate at 380°C for 4 hours to obtain the final catalyst.

Take 5ml of the above catalyst without dilution and fill it in a fixed bed reactor (Ф10×500mm). The reduction conditions are: 400°C, 0.5MPa, constant temperature for 12h, 800h ^-1 (v/v), using hydrogen in nitrogen, and the _H2 content is 10% (v/v), . The reaction conditions are: 170°C, 2.0MPa, 700h ^-1 (v/v), H ₂ /CO(mol)=2.5. Evaluation results: The CO conversion rate is 85.5%, the CH ₄ selectivity is 7.5%, and the inactivation rate within 720h is 0.02%.

Take 10ml of the above catalyst for evaluation in a 1L slurry bed reactor, the reduction conditions are 270°C, 01.2MPa, 500h ^-1 (v/v), _hydrogen in nitrogen is used, and the H content is 85% (v/v), Constant temperature 36h, 700rpm. After the reduction is complete, lower down to room temperature and switch to syngas for reaction. The reaction conditions are 195°C, 1.5MPa, 700h ^-1 (v/v), H ₂ /CO (v/v)=2.2, 600rpm. Evaluation results: the CO conversion rate is 88.8%, the CH ₄ selectivity is 6.7%, and the deactivation rate within 720h is 0.11%.

Embodiment 6:

According to the final catalyst composition, take 940.3 (wt.)% concentrated nitric acid and be mixed with 40L aqueous solution A, weigh 820g sodium metaaluminate and be mixed with 37.5L aqueous solution B, then weigh 52.1g ethyl orthosilicate and be mixed with 2.5L Ethanol solution C; first carry out co-current co-precipitation of solution A and solution B in a water bath at 85°C, and the volume flow rate of A and B is the same; after solution B is precipitated, continue to carry out co-current co-precipitation of solution A and solution C at 5°C Co-precipitation, the volume flow rate of A and C is the same; after the precipitation of solutions A and C is completed, age at 90°C for 12 hours; after aging, wash with deionized water until the sodium ion in the filtrate is less than 5ppm, filter to obtain a filter cake, filter The cake was dried in an oven at 105°C for 12 hours to obtain a silicon-containing alumina precursor; the obtained precursor was placed in a muffle furnace and calcined at 800°C for 4 hours to obtain a silicon-containing alumina; according to the final catalyst composition, weigh 654.8g Prepare an aqueous solution of cobalt nitrate hexahydrate, impregnate the same volume on the above-mentioned carrier, dry at 120°C for 10 hours, and calcinate at 400°C for 5 hours to obtain the final catalyst.

Take 5ml of the above catalyst without dilution and fill it in a fixed bed reactor (Ф10×500mm). The reduction conditions are: 450°C, 0.3MPa, constant temperature for 12h, 500h ^-1 (v/v), using hydrogen in nitrogen, and the _H2 content is 85% (v/v), . The reaction conditions are: 230°C, 2.0MPa, 1500h ^-1 (v/v), H ₂ /CO(mol)=2.0. Evaluation results: CO conversion rate is 52.3%, CH ₄ selectivity is 10.0%, and inactivation rate is 0.07% within 720h.

Take 10ml of the above catalyst in a 1L slurry bed reactor for evaluation, the reduction conditions are 330°C, 1.2MPa, 800h ^-1 (v/v), _hydrogen in nitrogen is used, and the H content is 45% (v/v), Constant temperature 20h, 700rpm. After the reduction is completed, lower the temperature to room temperature and switch to synthesis gas for reaction. The reaction conditions are 180°C, 2.5MPa, 1200h ^-1 (v/v), H ₂ /CO (v/v)=3.0, 750rpm. Evaluation results: The CO conversion rate is 77.5%, the CH ₄ selectivity is 2.5%, and the deactivation rate within 720h is 0.09%.

Embodiment 7:

According to final catalyst composition, take by weighing 128.6g 98 (wt.)% fuming nitric acid and be mixed with 2L aqueous solution A, take by weighing 164g sodium metaaluminate and be mixed with 1.8L aqueous solution B, then take by weighing 14.6g orthosilicate ethyl ester and prepare into 0.2L ethanol solution C; first carry out co-precipitation of solution A and solution B in a water bath at 60°C, and the volume flow rate of A and B is the same; Carry out co-current co-precipitation, the volume flow rate of A and C is the same; after the precipitation of solutions A and C is completed, age at 70°C for 10 hours; after aging, wash with deionized water until the sodium ion in the filtrate is less than 5ppm, and filter to obtain a filter cake , put the filter cake in an oven and dry at 95°C for 20 hours to obtain a silicon-containing alumina precursor; place the obtained precursor in a muffle furnace and roast at 500°C for 7 hours to obtain a silicon-containing alumina; according to the final catalyst composition, it is Take 1746g of cobalt nitrate hexahydrate to prepare an aqueous solution, impregnate the same volume on the above-mentioned carrier, dry at 110°C for 24 hours, and roast at 400°C for 4 hours to obtain the final catalyst. .

Take 5ml of the above catalyst without dilution and fill it in a fixed bed reactor (Ф10×500mm). The reduction conditions are: 390°C, 1.5MPa, constant temperature for 12h, 900h ^-1 (v/v), using hydrogen in nitrogen, and the _H2 content is 15% (v/v), . The reaction conditions are: 200°C, 2.4MPa, 1000h ^-1 (v/v), H ₂ /CO(mol)=2.4. Evaluation results: the CO conversion rate is 76.8%, the CH ₄ selectivity is 5.6%, and the deactivation rate within 720h is 0.01%.

Take 10ml of the above catalyst for evaluation in a 1L slurry bed reactor, the reducing conditions are 340°C, 0.7MPa, 800h ^-1 (v/v), _hydrogen in nitrogen, H content of 50% (v/v), Constant temperature 24h, 700rpm. After the reduction is complete, lower down to room temperature and switch to syngas for reaction. The reaction conditions are 205°C, 2.0MPa, 800h ^-1 (v/v), H ₂ /CO(v/v)=2.6, 650rpm. Evaluation results: CO conversion rate 92.3%, CH ₄ selectivity 2.7%, deactivation rate 0.1% within 720h.

Claims (3)

1. A kind of 1. alumina load cobalt fischer-tropsch synthetic catalyst, it is characterised in that catalyst by cobaltosic oxide, silica and Aluminum oxide forms, and its mole of composition is cobaltosic oxide：Silica：Aluminum oxide=0.1-0.25：0.02-0.2：1；

   And by being prepared including following method：

   （1）Formed by final catalyst, weigh nitric acid and be configured to water solution A, weigh sodium metaaluminate and be configured to aqueous solution B, then claim Silicon source is taken to be configured to ethanol solution C, solution A volume=B solution volume+C solution volume, wherein, nitric acid：（Sodium metaaluminate+silicon source） Amount ratio=0.95-1.1 of material：1；

   （2）Solution A and solution B are first subjected to co-precipitation at 50-85 DEG C of water-bath, A, B volume flow are identical, and solution B is sunk After shallow lake, solution A is continued into co-precipitation with solution C under mutually synthermal water-bath, A, C volume flow are identical；

   （3）After precipitation, the aging 2-24h at 70-90 DEG C；

   （4）After aging terminates, sodium ion is washed with deionized into filtrate and is less than 5ppm, is then filtrated to get filter cake, will filter Cake is placed in 90-120 DEG C of dry 10-24h and obtains silicon-aluminum containing presoma, and obtained presoma is calcined into 4-10h in 400-800 DEG C, Obtain silicon-containing alumina carrier；

   （5）Formed by final catalyst, weigh cobalt nitrate and be dissolved in water preparation solution, incipient impregnation carries in above-mentioned silicon-containing alumina Body, 10-24h is dried at 90-120 DEG C, 300-400 DEG C of roasting 4-10 h, final catalyst is made；

   Described silicon source is methyl silicate, tetraethyl orthosilicate, positive silicic acid propyl ester, one kind of butyl silicate.
2. 2. a kind of application of alumina load cobalt fischer-tropsch synthetic catalyst as claimed in claim 1, it is characterised in that described Fischer-Tropsch synthesis cobalt-based catalyst, reduced, reacted in fixed bed reactors；Reducing condition is：350-450 DEG C, 0.3- 1.5MPa, GHSV=300-1000h^-1, constant temperature 12-24h, using hydrogen reduction gas, H in nitrogen₂Volume content is 15 %-85%；Reaction Condition is：170-230 DEG C, 2.0-5.0Mpa, volume space velocity GHSV=700-2500h^-1, H₂/ CO volume ratios=2.0-2.5.
3. 3. a kind of application of alumina load cobalt fischer-tropsch synthetic catalyst as claimed in claim 1, it is characterised in that described Fischer-Tropsch synthesis cobalt-based catalyst, reduced, reacted in paste state bed reactor；Reducing condition is：270-320 DEG C, 0.2- 1.2MPa, GHSV=500-800h^-1, constant temperature 12-36h, using hydrogen reduction gas, H in nitrogen₂Volume content is 15%-85%, and rotating speed is 400-800rpm；Reaction condition is：170-230 DEG C, 2.0-3.0MPa, volume space velocity GHSV=700-2000h^-1, H₂/ CO volumes Than=2.0-3.0, rotating speed 400-800rpm.