Method for deep desulfurization of liquefied petroleum gas

Abstract

The application discloses a deep desulfurization method of liquefied petroleum gas, which comprises the following steps: (1) feeding the liquefied petroleum gas into an alcohol amine absorption tower to remove hydrogen sulfide; (2) feeding the liquefied petroleum gas and hydrogen gas after removal of hydrogen sulfide into a fixed bed reactor to react sulfides in the liquefied petroleum gas with dienes under the action of a sulfur transfer catalyst, and convert the sulfides into high-boiling macromolecular sulfides; and (3) feeding the effluent of step (2) into an absorption tower to perform absorption treatment by using an absorbent, obtaining refined liquefied petroleum gas products at the upper part of the absorption tower, and flowing rich absorbent from the bottom of the absorption tower; the desulfurization method can refine the liquefied petroleum gas under the condition of low olefin saturation rate, and can meet the requirement that the total sulfur content of the product is ≯2.0 mg / m 3 under the condition that the olefin saturation rate is ≯2.0%.

Description

TECHNICAL FIELD

[0001] The present application relates to a liquefied petroleum gas desulfurization method, in particular to a deep desulfurization treatment of liquefied petroleum gas raw material under the condition of low olefin saturation rate. BACKGROUND

[0002] The conventional distillation, catalytic cracking, delayed coking, catalytic reforming, hydrocracking and other devices of oil refinery will produce a large amount of liquefied petroleum gas. Traditionally, liquefied petroleum gas is mainly used as fuel; with the development of chemical technology, liquefied petroleum gas, especially the liquefied gas containing catalytic cracking and other liquefied gas contains a large amount of olefins, is more and more used in chemical field, such as polypropylene production, MTBE production, alkylation process and the like. The main components of liquefied petroleum gas are propane, propylene, butane and butene, etc., and some sulfides are also contained in untreated liquefied petroleum gas. The molecular weight of the sulfides contained in the liquefied petroleum gas is generally small and harmful, and the main components are hydrogen sulfide, carbonyl sulfide, mercaptan and sulfide, etc.

[0003] The traditional liquefied gas double desulfurization process is mainly Merox deodorization (Sweeten) process, and one of the shortcomings of double desulfurization (removing H2S and mercaptan) is that mercaptan (RSH) is only oxidized to disulfide (RSSR), and the total sulfur content is not reduced or is limitedly reduced; the other shortcoming is that the regenerated organic waste gas and alkali residue produced by the desulfurization device are both environmental pollutants difficult to be treated, and there are hidden dangers in environmental protection or safety.

[0004] CN200910233505.1 introduces a high-efficiency desulfurizer for high-acid petroleum and natural gas. Its main feature is to add a water-soluble nitrogen-containing organic solvent (alkaline nitrogen content ≥100g / L) to the fiber membrane reactor for desulfurization. Its advantages are higher desulfurization rate than the traditional alkanolamine method (such as N-methyldiethanolamine, MDEA); its disadvantage is that the nitrogen-containing organic solvent needs to be regenerated repeatedly, and the heat exchange process is complex and the energy consumption is high.

[0005] In recent years, the sulfidation method has been widely used to remove mercaptan from refinery hydrocarbon fractions, that is, to remove mercaptan by using the reaction between components in the raw material. Specifically, some hydrocarbon fractions contain mercaptan and highly reactive olefins and dienes (such as butene, isoprene, etc.), and the sulfidation reaction is to convert mercaptan into high-boiling sulfide by the reaction between mercaptan and active olefins, and then separate the formed high-boiling sulfide compounds from the hydrocarbon fraction by distillation, so as to achieve the purpose of removing mercaptan from the raw material.

[0006] US5851383 discloses a process for the removal of mercaptans from light olefins by mixing the C3-C5 fraction from a catalytic cracking unit with hydrogen and feeding the mixture into a fixed bed reactor, where the mercaptans in the fraction are converted to higher boiling sulfides by reaction with dienes in the presence of a sulfidation catalyst. The excess dienes are selectively hydrogenated to mono-olefins. The reaction product is then fed to a distillation column, where the light fraction, depleted in mercaptans, is removed from the top of the column, and the sulfides and heavier components are enriched in the bottom of the column. The catalyst used in this process is a Ni-based catalyst on an alumina support. The sulfidation reaction is carried out at a temperature of 125°C and a pressure of 4.1 MPa. The process described in this patent involves the hydrogenation and isomerization of some of the mono-olefins.

[0007] CN104194833A describes a process for the deep desulfurization of liquefied petroleum gas. The process involves the removal of H2S from the liquefied petroleum gas by extraction with an amine solution, followed by washing with water to remove the amine solution. The liquefied petroleum gas is then converted to higher boiling sulfides by hydroconversion in the presence of a sulfidized Mo-Ni / γ-Al2O3 catalyst. The hydroconversion product is then fed to a stabilizer column, where the low sulfur C5+ fraction is separated by distillation to produce a liquefied petroleum gas product with ultra-low sulfur content, which can be used as a feedstock for the production of MTBE or alkylate.

[0008] CN103965984A describes a process for the catalytic removal of mercaptans from liquefied petroleum gas. The process involves mixing the liquefied petroleum gas with hydrogen and feeding the mixture to a fixed bed reactor containing a Ni-Mo / γ-Al2O3 catalyst or a Ni-W / γ-Al2O3 catalyst, where the low boiling mercaptans are converted to higher boiling sulfides. The sulfidation product is then distilled in a distillation column to produce a liquefied petroleum gas product free of mercaptans. The disadvantage of this process is that it can only be used to treat liquefied petroleum gas that has been treated to remove carbonyl sulfide. The mercaptan content of the product exceeds 10µg / g after about 100 hours of operation. In addition, the distillation column requires a reboiler, which increases the energy consumption.

[0009] US7270737B2 describes a process for the removal of sulfur from hydrocarbon feedstocks, such as catalytic cracking gasoline. The process involves the selective hydrodesulfurization of the feedstock using a catalyst containing a Group VIII metal element (trade name HR845 catalyst, sulfidized form) to convert the low boiling mercaptans and dienes in the gasoline to higher boiling sulfides. The low sulfur content raffinate is then obtained by extraction in an extraction column. The desulfurization rate can be as high as 97.9% compared to the feedstock. The olefin saturation rate is also low, while the diene content is reduced. The disadvantage of this process is that it uses sulfolane as a solvent, which requires repeated regeneration and has a complex process flow. In addition, sulfolane is flammable, corrosive, and can cause burns and water pollution. SUMMARY

[0010] In view of the deficiencies in the prior art, the present application provides a deep desulfurization method for liquefied petroleum gas, which can refine liquefied petroleum gas under the condition of low olefin saturation rate, and meet the requirement of total sulfur content of product ≯2.0 mg / m 3 under the condition of olefin saturation rate ≯2.0% (wherein the olefin saturation rate refers to mono-olefin saturation rate).

[0011] The deep desulfurization method for liquefied petroleum gas of the present application comprises the following contents: (1) the liquefied petroleum gas raw material enters an alcohol amine absorption tower to remove hydrogen sulfide; (2) the liquefied petroleum gas from which hydrogen sulfide is removed and hydrogen enter a fixed bed reactor to react with diene in the liquefied petroleum gas under the action of a sulfur transfer catalyst to convert into high-boiling macromolecular sulfides; (3) the effluent of step (2) enters an absorption tower for absorption treatment by using an absorbent, and refined liquefied petroleum gas product is obtained at the upper part of the absorption tower, and rich absorbent flows out from the bottom of the tower.

[0012] The sulfur transfer catalyst of step (2) comprises a carrier and an active metal component; the carrier is graphene oxide modified γ-Al2O3, and the content of graphene oxide is 0.1wt%-10.0wt% based on the weight of the carrier, preferably 0.5wt%-8.0wt%; the active metal component is nickel and a group VIB metal, and the group VIB metal is Ni or W; the content of nickel is 5.0wt%-20.0wt% based on the weight of the catalyst, preferably 5.0wt%-10.0wt%; the content of the group VIB metal is 3.0wt%-14.0wt% based on the weight of the catalyst, preferably 3.0wt%-10.0wt%.

[0013] In the method of the present application, the liquefied petroleum gas raw material of step (1) is generally obtained from liquefied petroleum gas produced by processes such as atmospheric and vacuum distillation, catalytic cracking, delayed coking, catalytic reforming, hydrocracking, etc.; the liquefied petroleum gas raw material preferably has a composition of propylene content of 20.0v%-40.0v%, butene content of 10.0v%-30v%, butadiene content of 0.01v%-0.5v%, total sulfur content of 100-5000 mg / m 3 , mercaptan sulfur content of 50-200 mg / m 3 .

[0014] In the method of the present application, the alcohol amine liquid in the alcohol amine absorption tower is at least one of ethanol amine, diethanol amine and diisopropanol amine.

[0015] In the method of the present application, the preparation method of the sulfur transfer catalyst is as follows:

[0016] (a) mixing graphene oxide and γ-Al2O3, after first microwave treatment, adding alkaline solution for second microwave treatment, filtering, drying to obtain graphene oxide modified γ-Al2O3;

[0017] (b) adding graphene oxide modified γ-Al2O3 into water and kneading with forming aid, after drying and calcining, obtaining carrier;

[0018] (c) loading active metal component to the carrier to obtain sulfur transfer catalyst.

[0019] The forming aid includes one or more of peptizing agent and extrusion aid. The peptizing agent is one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, oxalic acid, etc. The extrusion aid refers to a substance that is beneficial to extrusion forming, such as one or more of sesbania gum, carbon black, graphite powder, citric acid, etc. The amount of forming aid is 1.0wt% to 10.0wt% of the carrier.

[0020] The first microwave treatment has the following conditions: microwave power is 500 to 900W, and treatment time is 0.5 to 3.0h. The second microwave treatment has the following conditions: microwave power is 500 to 800W, and treatment time is 1.0 to 4.0h.

[0021] The alkaline solution can be a solution of at least one of potassium hydroxide, sodium hydroxide, etc. The mass concentration of the alkaline solution is 5.0% to 40.0%. The volume ratio of the alkaline solution to graphene oxide and γ-Al2O3 is 1.5:1 to 2.5:1.

[0022] The active metal component solution is one or more of aqueous solution of chloride salt, sulfate salt, acetate salt, nitrate salt, molybdate salt of active metal.

[0023] The loading process can generally adopt the way of impregnation, such as spray impregnation. The carrier after impregnation is dried and calcined to obtain catalyst product.

[0024] The drying method and conditions are recognized by those skilled in the art. For example, the drying method can be air drying, oven drying, and air blowing drying. Preferably, the drying temperature can be room temperature to 400℃, preferably 100 to 350℃; the drying time is more than 0.5h, preferably 0.5 to 100h, more preferably 2 to 20h.

[0025] The calcination conditions are as follows: calcination temperature is 400 to 700℃, preferably 450 to 650℃, and calcination time is 0.5 to 100h, more preferably 0.5 to 10h.

[0026] The shape of the sulfur transfer catalyst of the present application is spherical, columnar or clover-shaped, the specific surface area is 200-300 m 2 / g, and the pore size is 6.5-7.5 nm.

[0027] The sulfur transfer catalyst used in the present application needs to be pre-sulfurized by using a conventional sulfurization method before use, so as to convert the metal oxide active precursor into a sulfide active phase with catalytic activity; the pre-sulfurization of the catalyst can be realized by in-situ sulfurization and ex-situ sulfurization, and the sulfurizing agent can be selected from dimethyl disulfide, hydrogen sulfide, carbon disulfide and other sulfides.

[0028] In the method of the present application, the reaction conditions in the fixed bed reactor in step (2) are as follows: the reaction pressure is 0-2.5 MPa, the reaction temperature is 20-200 ℃, the liquid gas feed volume space velocity is 0.2-20.0 h -1 , and the hydrogen / hydrocarbon volume ratio is 0-20:1; preferably, the operation conditions are as follows: the reaction pressure is 0-1.6 MPa, the reaction temperature is 20-120 ℃, the liquid gas feed volume space velocity is 0.2-10.0 h -1 , and the hydrogen / hydrocarbon volume ratio is 0-10:1.

[0029] In the method of the present application, the absorbent in step (3) is a petroleum distillate with a boiling point higher than that of the liquefied petroleum gas, which is selected from one or more of catalytic gasoline, coking gasoline, straight-run naphtha, hydrocracking naphtha, reforming product oil or reforming raffinate.

[0030] In the method of the present application, the rich absorbent flowing out from the bottom of the column in step (4) is subjected to hydrodesulfurization treatment, which can be realized by using a conventional hydrodesulfurization method.

[0031] Compared with the prior art, the method of the present application has the following characteristics:

[0032] In the present application, graphene-modified γ-Al2O3 is used as a carrier, which greatly improves the sulfur transfer capacity of sulfides in liquefied petroleum gas; meanwhile, under the condition of mild reaction conditions, low hydrogen / oil ratio and low reaction temperature, sulfides in liquefied petroleum gas almost completely react with dienes in liquefied petroleum gas to form macromolecular sulfides with a boiling point higher than that of liquefied petroleum gas, and olefins are almost not saturated.

[0033] The present application can produce products meeting the requirement of total sulfur content ≯2.0 mg / m 3 under the condition of olefin saturation rate ≯2.0%, and has the advantages of mild reaction conditions, low hydrogen consumption, good desulfurization effect, low olefin saturation rate and long reaction period, etc., and can meet the requirement of deep desulfurization of liquefied petroleum gas from different sources. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1Transmission electron microscope (TEM) of Comparative Example 1 catalyst;

[0035] Figure 2 Transmission electron microscope (TEM) of Comparative Example 2 catalyst;

[0036] Figure 3 Transmission electron microscope (TEM) of Example 1 catalyst;

[0037] Figure 4 Transmission electron microscope (TEM) of Example 2 catalyst;

[0038] Figure 5 Transmission electron microscope (TEM) of Example 3 catalyst;

[0039] Figure 6 Transmission electron microscope (TEM) of Example 4 catalyst. DETAILED DESCRIPTION

[0040] The method and effects of the present application are further illustrated below in conjunction with the accompanying drawings and examples, but do not limit the protection scope of the present application. In the present application, the specific surface area and pore volume are measured by low-temperature liquid nitrogen adsorption BET method.

[0041] Comparative Example 1

[0042] Take 100.0 g of pseudo-boehmite powder (Al2O3 dry basis content of 70 wt%), add 3.5 g of sesbania powder auxiliary agent accounting for 5 wt% of Al2O3 dry basis, 80 g of 5 wt% nitric acid aqueous solution, mix and roll the mixture into a plastic powder, and use an extruder to prepare cylindrical strips with a diameter of 1.5 mm. Dry at 120℃ for 6 hours, and calcine at 500℃ for 4 hours to prepare a γ-Al2O3 carrier.

[0043] Take 9.27 g of nickel nitrate, 0.88 g of ammonium molybdate, and 13.27 g of deionized water to make a solution, then immerse it in 20 g of the above-mentioned γ-Al2O3 carrier at 30℃ for 8 hours, dry at 120℃ for 6 hours, and calcine at 500℃ for 4 hours to prepare a catalyst, numbered R-1. The physical properties of the R-1 catalyst are listed in Table 1.

[0044] Figure 1 Transmission electron microscope (TEM) of Comparative Example 1 catalyst;

[0045] Comparative Example 2

[0046] The preparation method of the γ-Al2O3 carrier is the same as that of Comparative Example 1.

[0047] A solution was prepared by weighing 9.27 g of nickel nitrate, 0.78 g of ammonium tungstate and 13.27 g of deionized water, and then impregnating 20 g of the above-mentioned γ-Al2O3 carrier in an equal volume under the condition of 30°C for 8 h, drying at 120°C for 6 h, and calcining at 500°C for 4 h to prepare a catalyst, numbered R-2. The physical properties of the R-2 catalyst are listed in Table 1. Figure 2 The transmission electron microscope (TEM) image of the catalyst of Comparative Example 2.

[0048] Example 1

[0049] A solution was prepared by weighing 9.27 g of nickel nitrate, 0.78 g of ammonium tungstate and 13.27 g of deionized water, and then impregnating 20 g of the above-mentioned γ-Al2O3 carrier in an equal volume under the condition of 30°C for 8 h, drying at 120°C for 6 h, and calcining at 500°C for 4 h to prepare a catalyst, numbered R-2. The physical properties of the R-2 catalyst are listed in Table 1.

[0050] A solution was prepared by weighing 9.27 g of nickel nitrate, 0.78 g of ammonium tungstate and 13.27 g of deionized water, and then impregnating 20 g of the above-mentioned γ-Al2O3 carrier in an equal volume under the condition of 30°C for 8 h, drying at 120°C for 6 h, and calcining at 500°C for 4 h to prepare a catalyst, numbered R-2. The physical properties of the R-2 catalyst are listed in Table 1.

[0051] A solution was prepared by weighing 9.27 g of nickel nitrate, 0.78 g of ammonium tungstate and 13.27 g of deionized water, and then impregnating 20 g of the above-mentioned γ-Al2O3 carrier in an equal volume under the condition of 30°C for 8 h, drying at 120°C for 6 h, and calcining at 500°C for 4 h to prepare a catalyst, numbered R-2. The physical properties of the R-2 catalyst are listed in Table 1.

[0052] A solution was prepared by weighing 9.27 g of nickel nitrate, 0.78 g of ammonium tungstate and 13.27 g of deionized water, and then impregnating 20 g of the above-mentioned γ-Al2O3 carrier in an equal volume under the condition of 30°C for 8 h, drying at 120°C for 6 h, and calcining at 500°C for 4 h to prepare a catalyst, numbered R-2. The physical properties of the R-2 catalyst are listed in Table 1. Figure 3 The transmission electron microscope (TEM) image of the catalyst of Example 1.

[0053] Example 2

[0054] The preparation method of the graphene modified γ- Al2O3 support is the same as that of Example 1. 9.27 g of nickel nitrate, 0.78 g of ammonium tungstate and 13.27 g of deionized water are weighed to prepare a solution, which is then impregnated with 20 g of the graphene modified γ- Al2O3 support at 30°C for 8 h, dried at 120°C for 6 h, and calcined at 500°C for 4 h to prepare a catalyst, which is numbered as L-2 catalyst. The physical properties of the L-2 catalyst are listed in Table 1. Figure 4 The transmission electron microscopy (TEM) image of the catalyst of Example 2 is shown in Figure 2.

[0055] Example 3

[0056] The preparation method of the graphene modified γ- Al2O3 support is the same as that of Example 1. 4.64 g of nickel nitrate, 2.93 g of ammonium molybdate and 13.27 g of deionized water are weighed to prepare a solution, which is then impregnated with 20 g of the graphene modified γ- Al2O3 support at 30°C for 8 h, dried at 120°C for 6 h, and calcined at 500°C for 4 h to prepare a catalyst, which is numbered as L-3 catalyst. The physical properties of the L-3 catalyst are listed in Table 1. Figure 5 The transmission electron microscopy (TEM) image of the catalyst of Example 3 is shown in Figure 3.

[0057] Example 4

[0058] The preparation method of the graphene modified γ- Al2O3 support is the same as that of Example 1. 4.64 g of nickel nitrate, 2.60 g of ammonium tungstate and 13.27 g of deionized water are weighed to prepare a solution, which is then impregnated with 20 g of the graphene modified γ- Al2O3 support at 30°C for 8 h, dried at 120°C for 6 h, and calcined at 500°C for 4 h to prepare a catalyst, which is numbered as L-4 catalyst. The physical properties of the L-4 catalyst are listed in Table 1. Figure 6 The transmission electron microscopy (TEM) image of the catalyst of Example 4 is shown in Figure 4.

[0059] Comparative Example 3

[0060] This comparative example investigates the performance of the catalyst of Comparative Example 1.

[0061] The catalyst of Comparative Example 1 is first subjected to a conventional ex-situ presulfurization treatment, i.e., a selected sulfiding agent is loaded onto the catalyst in the oxidized state by impregnation, followed by low-temperature drying treatment.

[0062] A 10 mL of the new R-1 catalyst after pre-sulfidation was charged into a fixed bed reactor. First, hydrogen was introduced to increase the pressure, and the new R-1 catalyst was reacted at a hydrogen pressure of 1.0 MPa, a temperature of 320°C, and a hydrogen to hydrocarbon volume ratio of 100:1 for 2 h to completely change the R-1 catalyst into a sulfided state; then, the reaction pressure was maintained at 1.0 MPa, the hydrogen to hydrocarbon volume ratio was maintained at 5:1, the temperature was decreased to 60°C, and the volume space velocity was maintained at 10.0 h -1 The liquefied petroleum gas raw material from which hydrogen sulfide was removed was subjected to a hydrodesulfurization reaction; the reaction product was passed through an absorption tower filled with a petroleum fraction having a higher boiling point than the liquefied petroleum gas, and the macromolecular sulfides produced by the sulfur transfer and having a higher boiling point than the liquefied petroleum gas were retained in the absorption tower, and the final refined liquefied petroleum gas product was obtained at the upper end of the absorption tower.

[0063] Table 2 lists the analysis results of the liquefied gas raw material and the sulfidation reaction product. Table 3 lists the analysis results of the liquefied gas raw material and the final refined liquefied petroleum gas product after absorption in the absorption tower.

[0064] Comparative Example 4

[0065] This comparative example investigated the performance of the catalyst of Comparative Example 2. The evaluation method was the same as that of Comparative Example 3.

[0066] Table 2 lists the analysis results of the liquefied gas raw material and the sulfidation reaction product. Table 3 lists the analysis results of the liquefied gas raw material and the final refined liquefied petroleum gas product after absorption in the absorption tower.

[0067] Examples 5 to 8

[0068] This example investigated the performance of the catalyst of Example 1. The evaluation method was the same as that of Comparative Example 3. Table 2 lists the analysis results of the liquefied gas raw material and the sulfidation reaction product. Table 3 lists the analysis results of the liquefied gas raw material and the final refined liquefied petroleum gas product after absorption in the absorption tower.

[0069] Table 1 Catalyst properties

[0070]

[0071] Table 2 Liquefied gas raw material and sulfidation product properties

[0072]

[0073] Table 3 Liquefied gas raw material and final refined liquefied petroleum gas product properties

[0074]

[0075] As can be seen from Tables 2 and 3, using the method of the present application, the sulfide content in the liquefied petroleum gas can be reduced to 10 mg / m 3The sulfides in the liquefied petroleum gas can be almost converted into macromolecular sulfides with a boiling point higher than that of the liquefied petroleum gas by using the catalyst, and after absorption by an absorption tower, the total sulfur content in the final refined liquefied petroleum gas product is ≯2.0 mg / m 3 Meanwhile, the olefin saturation rate is ≯2.0%.

[0076] Figure 2 Figure 3 The transmission electron microscope image of the comparative catalyst, Figures 3-6 The transmission electron microscope image of the catalyst of the present application. It can be seen that the active metal of the catalyst of the present application is more distributed on the graphene rod after the graphene modification of γ-Al2O3, and the sulfur transfer activity of the catalyst of the present application is improved.​

Claims

1. A method for deep desulfurization of liquefied petroleum gas, characterized by The application relates to a sulfur transfer catalyst and a preparation method thereof, and a method for removing sulfur from liquefied petroleum gas.

2. The method of claim 1, wherein: The liquefied petroleum gas raw material in step (1) is one or more of liquefied petroleum gas produced by atmospheric-vacuum distillation, catalytic cracking, delayed coking, catalytic reforming, and hydrocracking process devices; the composition of the liquefied petroleum gas raw material is that the propylene content is 20.0v%~40.0v%, the butene content is 10.0v%~30v%, the butadiene content is 0.01v%~0.5v%, the total sulfur content is 100~5000mg / m 3 , and the sulfur content in mercaptan is 50~200mg / m 3 .

3. The method of claim 1, wherein: The sulfur transfer catalyst comprises a carrier and an active metal component; the carrier is graphene oxide modified gamma-Al2O3, and the content of the graphene oxide is 0.1wt%-10.0wt% based on the weight of the carrier; the active metal component is nickel and a group VIB metal, and the group VIB metal is Ni or W; the content of the nickel is 5.0wt%-20.0wt% based on the weight of the catalyst, and the content of the group VIB metal is 3.0wt%-14.0wt% based on the weight of the catalyst; the preparation method of the sulfur transfer catalyst comprises the following steps: (a) mixing graphene oxide and gamma-Al2O3, carrying out first microwave treatment, adding an alkaline solution to carry out second microwave treatment, filtering, and drying to obtain graphene oxide modified gamma-Al2O3; (b) adding the graphene oxide modified gamma-Al2O3 into water and a molding aid, kneading, extruding, drying, and calcining to obtain the carrier; and (c) loading the active metal component onto the carrier to prepare the sulfur transfer catalyst.

4. The method of claim 1, wherein: In the preparation method of the sulfur transfer catalyst, the molding aid comprises a peptizing agent and an extrusion aid; the peptizing agent is one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid and oxalic acid; the extrusion aid is one or more of sesbania powder, carbon black, graphite powder and citric acid; and the amount of the molding aid is 1.0wt%-10.0wt% of the carrier.

5. The method of claim 1, wherein: In the preparation method of the sulfur transfer catalyst, the first microwave treatment is carried out under the following conditions: the microwave power is 500-900W, and the treatment time is 0.5-3.0h; and the second microwave treatment is carried out under the following conditions: the microwave power is 500-800W, and the treatment time is 1.0-4.0h.

6. The method of claim 1, wherein: In the preparation method of the sulfur transfer catalyst, the alkaline solution is at least one of potassium hydroxide and sodium hydroxide, the mass concentration of the alkaline solution is 5.0%-40.0%, and the volume of the alkaline solution is 1.5:1-2.5:1 of the total volume of the graphene oxide and the gamma-Al2O3.

7. The method of claim 1, wherein: The reaction conditions in the fixed bed reactor in step (2) are as follows: reaction pressure 0-2.5 MPa, reaction temperature 20-200°C, liquefied gas feed volume space velocity 0.2-20.0 h -1 and hydrogen hydrocarbon volume ratio 0-20:

1.

8. The method of claim 1, wherein: The reaction conditions in the fixed bed reactor in step (2) are as follows: reaction pressure 0-1.6 MPa, reaction temperature 20-120°C, liquefied gas feed volume space velocity 0.2-10.0 h -1 and hydrogen hydrocarbon volume ratio 0-10:

1.

9. The method of claim 1, wherein: In the preparation method of the sulfur transfer catalyst, the drying is carried out under the following conditions: the drying temperature is room temperature-400 DEG C, and the drying time is 0.5-100h; and the calcining is carried out under the following conditions: the calcining temperature is 400-700 DEG C, and the calcining time is 0.5-100h.

10. The method of claim 1, wherein: In step (3), the absorbent is a petroleum distillate with a boiling point higher than that of the liquefied gas, and is one or more of catalytic gasoline, coking gasoline, straight-run naphtha, hydrocracking naphtha, reforming generated oil or reforming raffinate oil. The rich absorbent flowing out from the bottom of the tower in step (3) is subjected to hydrodesulfurization treatment.

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