Adsorbent for removing oxides in Fischer-Tropsch synthetic oil as well as preparation method and application of adsorbent

Abstract

The invention provides an adsorbent for removing oxides in Fischer-Tropsch synthetic oil and a preparation method and application thereof, the adsorbent is composed of 75%-85% of a Y-type molecular sieve, 15%-25% of a binder and 2%-5% of double active metals (selected from any two of Mg, Ca, Fe, Co, Ni, Cu, Zn, Ag and Ba) based on the Y-type molecular sieve, the microspheres of 80-200 microns are prepared through alkali pretreatment, metal impregnation, spray drying and calcination. The adsorbent can remove oxides such as alcohol, aldehyde, ketone, acid and ester in oil to below 1ppm in a fixed bed or simulated moving bed process, and is simple and convenient in process, low in cost and wide in application range.

Description

Technical Field

[0001] The present invention relates to the technical field of adsorption separation, and in particular to an adsorbent for removing oxygenates from Fischer-Tropsch synthetic oil, and a preparation method and application thereof. Background Art

[0002] With the continuous advancement of high-quality development, the contradiction between the large-scale use of fossil fuels and the green energy economy has become increasingly prominent. This has not only constrained economic development but also brought about the climate crisis. Fischer-Tropsch synthesis technology can convert other carbon-containing resources into liquid oil products and common raw materials for the chemical industry. Therefore, this technology can replace petroleum-based liquid fuels and oil products such as gasoline, diesel, and lubricants.

[0003] The Fischer-Tropsch synthesis reaction can generally be achieved at 300-350°C and 200-250°C on different catalysts. The products mainly include various organic compounds such as alkanes, alkenes, aldehydes, ketones, alcohols, acids, and esters, with alkanes and alkenes being the main components. In addition, the product also contains approximately 0.1%-10% oxygenates. Most current processes can reduce the oxygenate content to below 100 ppm. However, for industries requiring high-purity oil products, further removal of oxygenates from the oil is necessary. Therefore, improving the adsorbent's selectivity for oxygenates has become an urgent issue to improve oil purity.

[0004] CN113621402A discloses a method for separating Fischer-Tropsch synthetic oil, in which the synthetic oil is sequentially introduced into a hydroprotection reactor and a hydrofining reactor, where it is contacted with a catalyst for reaction to carry out olefin saturation and hydrodeoxygenation reactions. The reaction effluent of the hydrofining reactor is separated to obtain hydrogenated oil which is introduced into a supplementary refining adsorption tank of an adsorption deoxygenation unit, where it is contacted with an adsorbent for adsorption deoxygenation reactions, ultimately obtaining a liquid wax fraction and a wax oil fraction. The hydrogenation process is prone to catalyst coking and carbon deposition, resulting in a short catalyst life and high process costs.

[0005] CN111718748A discloses a method for removing oxygenates from Fischer-Tropsch oil. The Fischer-Tropsch oil is subjected to atmospheric and vacuum fractionation to obtain a first fraction, a second fraction, and a third fraction. The first fraction is extracted with a methanol-water solution, the second fraction with an ethanol-water solution, and the third fraction with an ethanol-water solution. Finally, all the raffinate phases are washed with water to obtain a deoxygenated and refined Fischer-Tropsch oil. However, the oxygenate content is still high, making subsequent utilization of olefins unreliable, and the oil yield needs to be improved.

[0006] CN107338069A discloses a method for removing trace organic oxygenates from light oil. The method uses a fixed-bed adsorption process to adsorb oxygenated compounds in Fischer-Tropsch oil after hydrogenation treatment. After removing the oxygenates, the content can be reduced to below 5 ppm. However, the method is only suitable for removing trace oxygenates from Fischer-Tropsch synthesized light oil, and its scope of use is limited.

[0007] The above patents adopt hydrogenation, extraction, fixed bed adsorption and other methods to remove the oxides in the Fischer-Tropsch synthetic oil, but there are problems such as incomplete removal, limited scope of application and high process cost. Summary of the Invention

[0008] The present invention mainly solves the problem of deep removal of oxygenated compounds (such as alcohols, aldehydes, ketones, acids, esters, etc.) in Fischer-Tropsch synthetic oil. In traditional processes, although the content of oxygenated compounds can be reduced to a lower level, it is still difficult for subsequent processing of high-purity oil products, and there are problems such as incomplete removal, high process costs, and short catalyst life. The present invention aims to provide an adsorbent for removing oxygenated compounds from Fischer-Tropsch synthetic oil, as well as its preparation method and application. The adsorbent is based on a Y-type molecular sieve, which is pretreated with alkaline solution, and then modified by joint impregnation with dual active metals (selected from Mg, Ca, Fe, Co, Ni, Cu, Zn, Ag, Ba, etc.), and then mixed with a binder and an additive, and then spray-dried to prepare adsorbent microspheres with a particle size of 80 to 200 microns. This adsorbent can be used in fixed-bed, simulated moving-bed and coupled distillation processes to deeply remove oxygenated substances such as alcohols, aldehydes, ketones, acids and esters with different carbon numbers from Fischer-Tropsch synthetic oil, reducing their content to below 1 ppm, thereby meeting the requirements for high-purity oil products and chemical raw materials.

[0009] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0010] According to a first aspect of the present invention, there is provided an adsorbent for removing oxygenates from Fischer-Tropsch synthetic oil, comprising, based on the weight of the adsorbent, 75%-85% of a Y-type molecular sieve, 15%-25% of a binder, and 2%-5% of a dual-active metal, calculated on the basis of the weight of the Y-type molecular sieve.

[0011] The biactive metals are selected from any two of Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Ag, Cs and Ba;

[0012] The Fischer-Tropsch synthetic oil contains alcohols, aldehydes, ketones, acids and ester-type oxygenates with different carbon numbers, and the mass proportion of the oxygenates is 0.1wt%-15wt%, of which alcohols account for about 90%.

[0013] As a preferred embodiment, the biactive metals are selected from any two of Mg, Ca, Fe, Co, Ni, Cu, Zn, Ag and Ba; and / or,

[0014] The volume ratio of the metal salt solutions corresponding to the dual active metals is between 1:1 and 1:4.

[0015] According to a second aspect of the present invention, a method for preparing the above-mentioned adsorbent is further provided, comprising the following steps:

[0016] Step 1: treating the Y-type molecular sieve with an alkaline solution, followed by filtering, washing and drying to obtain an alkaline-treated Y-type molecular sieve;

[0017] Step 2: Immersing the alkali-treated Y-type molecular sieve in a metal salt solution to achieve dual-active metal loading, followed by filtration, drying and calcination to obtain a dual-active metal loaded Y-type molecular sieve;

[0018] Step 3: The obtained dual-active metal-loaded Y-type molecular sieve is evenly mixed with a binder and an additive, and then spray-dried to form particles, which are then calcined to finally obtain an adsorbent with a particle size of 80 to 200 microns.

[0019] In some technical solutions, in step 1, the pH value of the alkaline solution is 8-12, preferably 9-11, the alkali treatment temperature is 25°C-90°C, the treatment time is 2h-8h, and the mass ratio of Y-type molecular sieve to alkaline solution is 1:1-1:5.

[0020] In some technical solutions, in step 1, the alkaline solution is prepared from one or more of NaOH, KOH, NH3·H2O, Na2CO3, NaHCO3, tetramethylammonium hydroxide or tetraethylammonium hydroxide.

[0021] In some technical solutions, in step 2, the metal is loaded by impregnation, wherein the metal salt solution is one or more of a nitrate solution and an acetate solution.

[0022] In some technical solutions, in step 2, the concentration of the metal salt solution is 0.1 mol / L-2 mol / L; the metal loading treatment time is 0.5 h-12 h; and the treatment temperature is 25° C.-80° C.

[0023] In some technical solutions, in step 2, the drying temperature is 60°C-120°C; and the calcination temperature is 400°C-550°C.

[0024] In some technical solutions, in step three, the binder is any one of aluminum sol, silica sol, kaolin, attapulgite, and bentonite, and the auxiliary agent is any one of carboxymethyl cellulose, water-soluble starch, and carbon black.

[0025] In some technical solutions, in step three, the air compressor pressure for spray drying is 1MPa-2MPa, the inlet temperature is 150℃-250℃, the outlet temperature is 50℃-90℃, and the feed rate is controlled to be 0.5mL / min-2ml / min; the particles in the cyclone separator are collected and calcined, the calcination temperature is 400℃-550℃, and the heating rate is 3℃ / min-10℃ / min.

[0026] The above-mentioned adsorbent provided by the present invention can be used for deep removal of alcohol, aldehyde, ketoester and oxygenated compounds in Fischer-Tropsch synthetic oil, and can also be used for removal of a small amount of alcohol, aldehyde, ketoester and oxygenated compounds in other hydrocarbon systems.

[0027] According to a third aspect of the present invention, there is further provided the use of the above-mentioned adsorbent or the adsorbent prepared by the above-mentioned preparation method in removing oxygenates from Fischer-Tropsch synthetic oil.

[0028] The adsorbent is suitable for fixed bed process, fixed bed coupled distillation process, multi-tower parallel process, multi-tower parallel coupled distillation process, simulated moving bed process, simulated moving bed coupled distillation process and multi-stage simulated moving bed process.

[0029] In some technical solutions, the simulated moving bed process is a sequential switching simulated moving bed process, the adsorption bed layers are 6-24 layers, and the desorbent is a mixture of alkanes and alcohol, aldehyde, ketoester and oxygenate-containing compounds, wherein the mass fraction of alkanes is 70%-95%.

[0030] The present invention adopts the above technical solution to have at least the following beneficial effects:

[0031] 1. This invention forms an adsorbent with a well-defined pore structure and excellent surface activity by treating Y-type molecular sieves with alkali and modifying them with dual active metals. This adsorbent is highly selective for adsorbing various oxygenates (especially alcohols, aldehydes, ketones, acids, and esters) in Fischer-Tropsch oils, significantly increasing the removal depth and ultimately controlling the oxygenate content to below 1 ppm, significantly improving oil purity.

[0032] 2. The entire preparation process of the present invention adopts conventional alkali treatment, impregnation, spray drying and calcination steps. The process conditions of each step are clear and easy to control, which not only ensures the uniformity and activity of the adsorbent, but also simplifies the process and reduces equipment requirements, facilitates large-scale application in industrial production, and reduces production costs.

[0033] 3. The adsorbent described in the present invention is not only suitable for traditional fixed-bed processes, but can also be used in fixed-bed coupled distillation, multi-tower parallel, and simulated moving bed processes. In particular, in the sequential switching simulated moving bed process, the configuration of multi-layer adsorption beds and an optimized desorbent system (a mixture of alkanes and alcohols, aldehydes, ketones, and esters) achieves efficient removal of trace oxygenates from Fischer-Tropsch oils, improving both process applicability and economic efficiency.

[0034] 4. The adsorbent prepared by this invention, modified with dual-active metal loading and subsequently granulated, not only exhibits high chemical selectivity for target substances but also significantly improves mechanical strength and thermal stability. Whether operated under high-temperature, high-pressure conditions in a fixed bed or in continuous cycles in a simulated moving bed process, it maintains long-term, stable deoxidation performance, extending process lifecycles and reducing maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is one of the scanning electron micrographs of the adsorbent of Example 1 of the present invention specification;

[0036] Figure 2 This is the second scanning electron microscope image of the adsorbent of Example 1 of the present invention. DETAILED DESCRIPTION

[0037] The present invention is further described below with reference to the embodiments, but the present invention is not limited in any way. Any changes or substitutions made based on the technical teachings of the present invention fall within the scope of protection of the present invention.

[0038] The determination method of the oxygenate removal performance of the adsorbent in the embodiment of the present application is as follows: Fischer-Tropsch synthetic oil C8-C 12 The distillate is the raw material, which contains alkanes, alkenes, cycloalkanes, aromatics, and oxygenates. The total mass fraction of oxygenates is about 12% by weight, of which the alcohol content is about 8% by weight, the ketone content is about 3% by weight, and the aldehyde content is about 1% by weight. After the adsorbent is loaded into the simulated moving bed, a sequential switching simulated moving bed process is used, with 12-18 adsorption beds. The adsorption separation temperature is 40°C-120°C, and the adsorption pressure is 0.5MPa-2MPa. The desorbent is a mixture of alkanes and aldehydes, ketones, and alcohols containing oxygenates, with the mass fraction of alkanes being 70%-95%. Two streams are extracted from the two outlets of the simulated moving bed: one is a hydrocarbon-rich component, and the other is an oxygenate-rich component. The oxygenate content in the hydrocarbon-rich component is as low as less than 1ppm (without desorbent).

[0039] In the following examples, component analysis was performed using a gas chromatograph-mass spectrometer, a SHIMADZU GCMS-QP2020NX gas chromatograph-mass spectrometer, with FID and MS as detectors and a 19091s-001PONA analytical column.

[0040] The invention is described below by way of examples, but is not limited to these examples.

[0041] Comparative Example 1

[0042] To 1200 g of Y-type molecular sieve, 2400 g of a pH-9 NH₃·H₂O solution was added and treated at 60°C for 4 h. The mixture was then filtered, washed, dried at 90°C for 15 h, and calcined at 550°C for 4 h. The metal-free Y-type molecular sieve was then mixed with 300 g of alumina sol binder and 12 g of carboxymethyl cellulose. 1.2 L of water was added to form a suspension, which was then dried in a spray dryer at a feed rate of 2 mL / min. The spray dryer's air compressor pressure was set to 1.5 MPa, the inlet temperature was 180°C, and the outlet temperature was 60°C. The particles were collected in a cyclone separator, heated at a rate of 3°C / min, and calcined at 550°C for 4 h to obtain metal-free adsorbent microspheres. The adsorbent evaluation results are shown in Table 1.

[0043] Comparative Example 2

[0044] 3600 g of Na2CO3 solution with pH = 11 was added to 1200 g of Y-type molecular sieve, treated at 90°C for 6 h, and then filtered, washed and dried; an equal volume of 0.2 mol / L silver nitrate solution was added to the dried alkaline solution-modified Y-type molecular sieve until it was completely immersed, impregnated at 60°C for 6 h, then dried at 90°C for 15 h, and calcined at 550°C for 4 h; then 1200 g of active metal Ag-loaded Y-type molecular sieve was evenly mixed with 400 g of silica sol binder and 16 g of water-soluble starch, 1.5 L of water was added to form a suspension, and dried by a spray dryer at a feed rate of 1.5 mL / min. The air compressor pressure of the spray dryer was set to 2 MPa, the inlet temperature was 180°C, and the outlet temperature was 60°C. The particles in the cyclone separator were collected, the heating rate was 5°C / min, and the particles were calcined at 550°C for 4 h to obtain active metal Ag-loaded adsorbent microsphere particles. The adsorbent evaluation results are shown in Table 1.

[0045] Example 1

[0046] 2400 g of NaOH solution with pH = 9 was added to 1200 g of Y-type molecular sieve, and the mixture was treated at 60 ° C for 4 h, followed by filtration, washing and drying. Equal volumes of 0.15 mol / L ferric nitrate and 0.15 mol / L cobalt nitrate solutions were added to the dried alkaline solution-modified Y-type molecular sieve until it was completely immersed, and the mixture was immersed at 40 ° C for 4 h, dried at 90 ° C for 15 h, and calcined at 550 ° C for 4 h. Then 1200 g of Y-type molecular sieve loaded with dual active metals Fe and Co was added. The sub-sieve was mixed evenly with 300g of aluminum sol binder and 12g of carboxymethyl cellulose, and 1.2L of water was added to form a suspension. The suspension was dried by a spray dryer at a feed rate of 2mL / min. The air compressor pressure of the spray dryer was set to 1.5MPa, the inlet temperature was 180℃, and the outlet temperature was 60℃. The particles in the cyclone separator were collected, the heating rate was 3℃ / min, and the particles were calcined at 550℃ for 4h to obtain adsorbent microspheres loaded with dual active metals Fe and Co. The adsorbent evaluation results are shown in Table 1, and the adsorbent morphology is shown in Table 1. Figure 1 and Figure 2 .

[0047] Example 2

[0048] The specific process is the same as in Example 1, except that the dual active metals are changed to Fe and Ni. The adsorbent evaluation results are shown in Table 1.

[0049] Example 3

[0050] The specific process is the same as in Example 1, except that the dual active metals are changed to Co and Ni. The adsorbent evaluation results are shown in Table 1.

[0051] Example 4

[0052] 6000 g of NH3·H2O solution with pH=10 was added to 1200 g of Y-type molecular sieve, and the mixture was treated at 25°C for 8 h, followed by filtration, washing and drying. Equal volumes of 0.1 mol / L calcium nitrate and 0.2 mol / L copper nitrate solution were added to the dried alkaline solution-modified Y-type molecular sieve until it was completely immersed, and the mixture was immersed at 60°C for 8 h, dried at 90°C for 15 h, and calcined at 550°C for 4 h. 1200 g of Y-type molecular sieve loaded with dual active metals Ca and Cu was then added. The molecular sieve was mixed uniformly with 300 g of kaolin binder and 24 g of water-soluble starch. 1.5 L of water was added to form a suspension. The suspension was then dried in a spray dryer at a feed rate of 2 mL / min. The spray dryer's air compressor pressure was set to 1.5 MPa, the inlet temperature was 180°C, and the outlet temperature was 80°C. The particles were collected from a cyclone separator, heated at a rate of 3°C / min, and calcined at 550°C for 6 h to obtain adsorbent microspheres loaded with the dual active metals Ca and Cu. The adsorbent evaluation results are shown in Table 1.

[0053] Example 5

[0054] The specific process was the same as in Example 4, except that the metal salt solution contained equal volumes of 0.1 mol / L magnesium nitrate and 0.2 mol / L barium nitrate. The adsorbent evaluation results are shown in Table 1.

[0055] Example 6

[0056] 4800 g of Na2CO3 solution with pH = 11 was added to 1200 g of Y-type molecular sieve, treated at 90 ° C for 6 h, then filtered, washed and dried; 0.2 mol / L zinc nitrate and 0.2 mol / L silver nitrate solution with a volume ratio of 1:2 were added to the dried alkaline solution-modified Y-type molecular sieve until it was completely immersed, immersed at 60 ° C for 6 h, dried at 90 ° C for 15 h, and calcined at 550 ° C for 4 h; then 1200 g of dual active metal Zn and Ag loaded Y-type molecular sieve was uniformly mixed with 400g of silica sol binder and 16g of carboxymethyl cellulose. 1.2L of water was added to form a suspension. The suspension was then dried in a spray dryer at a feed rate of 1.5mL / min. The spray dryer's air compressor pressure was set to 2MPa, the inlet temperature was 180°C, and the outlet temperature was 60°C. The particles were collected from a cyclone separator, heated at a rate of 5°C / min, and calcined at 550°C for 4h to obtain adsorbent microspheres loaded with dual active metals Zn and Ag. The adsorbent evaluation results are shown in Table 1.

[0057] Example 7

[0058] The specific process was the same as in Example 6, except that the metal salt solution was 0.1 mol / L magnesium nitrate and 0.2 mol / L barium nitrate in a volume ratio of 1:2. The adsorbent evaluation results are shown in Table 1.

[0059] Example 8

[0060] 3600 g of tetramethylammonium hydroxide solution with a pH of 10 was added to 1200 g of Y-type molecular sieve, and the mixture was treated at 80 ° C for 4 h, followed by filtration, washing and drying. 0.15 mol / L ferric nitrate and 0.15 mol / L silver nitrate solution with a volume ratio of 1:4 were added to the dried alkaline solution-modified Y-type molecular sieve until it was completely immersed, and the mixture was immersed at 60 ° C for 6 h, dried at 90 ° C for 15 h, and calcined at 550 ° C for 4 h. 1200 g of active metal Fe and Ag-loaded Y-type molecular sieve was uniformly mixed with 400 g of bentonite binder and 12 g of carbon black. 1.6 L of water was added to form a suspension. The suspension was then dried in a spray dryer at a feed rate of 2 mL / min. The spray dryer's air compressor pressure was set to 2 MPa, the inlet temperature was 180°C, and the outlet temperature was 60°C. The particles were collected from a cyclone separator, heated at a rate of 3°C / min, and calcined at 550°C for 6 h to obtain adsorbent microspheres loaded with active metals Fe and Ag. The adsorbent evaluation results are shown in Table 1.

[0061] Example 9

[0062] The specific process was the same as in Example 8, except that the metal salt solution was 0.15 mol / L cobalt nitrate and 0.15 mol / L barium nitrate in a volume ratio of 1:4. The adsorbent evaluation results are shown in Table 1.

[0063] Table 1. Adsorbent evaluation results

[0064]

[0065]

[0066] Table 2. Adsorbent mechanical wear rate data

[0067] adsorbent Speed (rpm) Time (h) Initial mass (g) Mass after wear (g) Wear rate (%) Comparative Example 1 500 1 10 9.6 4 Comparative Example 2 500 1 10 9.7 3 Example 1 500 1 10 9.88 1.2 Example 2 500 1 10 9.82 1.8 Example 3 500 1 10 9.9 1 Example 4 500 1 10 9.85 1.5 Example 5 500 1 10 9.92 0.8 Example 6 500 1 10 9.8 2 Example 7 500 1 10 9.95 0.5 Example 8 500 1 10 9.75 2.5 Example 9 500 1 10 9.83 1.7

[0068] The above-described embodiments merely represent several implementation methods of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. An adsorbent for removing oxygenates from Fischer-Tropsch oil, characterized in that: Based on the weight of the adsorbent, it contains 75%-85% of Y-type molecular sieve, 15%-25% of binder, and 2%-5% of dual active metal based on the Y-type molecular sieve. The biactive metals are selected from any two of Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Ag, Cs and Ba; The Fischer-Tropsch synthetic oil contains alcohols, aldehydes, ketones, acids and esters containing oxygenates with different carbon numbers, and the weight proportion of the oxygenates is 0.1 wt%-15 wt%.

2. The adsorbent according to claim 1, characterized in that The biactive metals are selected from any two of Mg, Ca, Fe, Co, Ni, Cu, Zn, Ag and Ba; and / or The volume ratio of the metal salt solutions corresponding to the dual active metals is between 1:1 and 1:

4.

3. The method for preparing the adsorbent according to claim 1 or 2, characterized in that: The following steps are involved: Step 1: treating the Y-type molecular sieve with an alkaline solution, followed by filtering, washing and drying to obtain an alkaline-treated Y-type molecular sieve; Step 2: Immersing the alkali-treated Y-type molecular sieve in a metal salt solution to achieve dual-active metal loading, followed by filtration, drying and calcination to obtain a dual-active metal loaded Y-type molecular sieve; Step 3: The obtained dual-active metal-loaded Y-type molecular sieve is evenly mixed with a binder and an additive, and then spray-dried to form particles, which are then calcined to finally obtain an adsorbent with a particle size of 80 to 200 microns.

4. The preparation method according to claim 3, characterized in that In step one, The mass ratio of the Y-type molecular sieve to the alkaline solution is 1:1-1:5; and / or, The alkaline solution is prepared from one or more of NaOH, KOH, NH3·H2O, Na2CO3, NaHCO3, tetramethylammonium hydroxide or tetraethylammonium hydroxide; and / or, The pH value of the alkaline solution is 8-12, the alkali treatment temperature is 25° C.-90° C., and the alkali treatment time is 2 h-8 h.

5. The preparation method according to claim 3, characterized in that In step 2, The concentration of the metal salt solution is 0.1 mol / L-2 mol / L, the metal loading treatment time is 0.5 h-12 h, and the treatment temperature is 25° C.-80° C.; and / or, The metal salt solution is one or more of a nitrate solution and an acetate solution; and / or, The drying temperature is 60°C-120°C, and the calcining temperature is 400°C-550°C.

6. The preparation method according to claim 3, characterized in that In step three, The binder is any one of aluminum sol, silica sol, kaolin, attapulgite, and bentonite; the auxiliary agent is any one of carboxymethyl cellulose, water-soluble starch, and carbon black; and / or, The air compressor pressure of the spray drying is 1MPa-2MPa, the inlet temperature is 150°C-250°C, the outlet temperature is 50°C-90°C, and the feed rate is controlled to be 0.5mL / min-2ml / min; the particles in the cyclone separator are collected and calcined, the calcination temperature is 400°C-550°C, and the heating rate is 3°C / min-10°C / min.

7. Use of the adsorbent according to any one of claims 1 to 2 or the adsorbent prepared by the preparation method according to any one of claims 3 to 6 in removing oxygenates from Fischer-Tropsch synthetic oil, characterized in that: The adsorbent is suitable for fixed bed process, fixed bed coupled distillation process, multi-tower parallel process, multi-tower parallel coupled distillation process, simulated moving bed process, simulated moving bed coupled distillation process and multi-stage simulated moving bed process.

8. The use according to claim 7, characterized in that The simulated moving bed process is a sequential switching simulated moving bed process, the adsorption bed has 6-24 layers, the desorbent is a mixture of alkanes and alcohol-aldehyde-ketoester oxides, wherein the mass fraction of alkanes is 70%-95%.

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