A bimetallic modified manganese oxide molecular sieve type adsorbent, a preparation method and application thereof

Abstract

The application relates to the technical field of petroleum refining, in particular to a bimetallic modified manganese oxide molecular sieve type adsorbent and a preparation method and application thereof, wherein the adsorbent comprises a manganese oxide carrier and an active component, and is characterized in that the manganese oxide carrier is MnO x -ZSM-5, MnO x The mass proportion in the carrier is 10-15 wt%, and x=1.5-2.0; the active component is Co and Cu. The bimetallic modified manganese oxide molecular sieve type adsorbent prepared by the application can directly remove sulfur-containing compounds in sulfur-containing alkylated oil at room temperature or a lower temperature (lower than 100 DEG C), the desulfurization adsorbent is low in cost, high in desulfurization precision, high in sulfur capacity and single-pass conversion rate, the desulfurization method is convenient in process and simple in operation, and is beneficial to industrial popularization.

Description

Technical Field

[0001] This invention relates to the field of petroleum refining technology, specifically to a bimetallic modified manganese oxide molecular sieve adsorbent, its preparation method, and its application. Background Technology

[0002] The presence of sulfur in fuel oil reduces its oxidation stability; excessive sulfur content can cause corrosion of metal equipment; and the combustion of sulfur-containing automotive fuel oil produces SO₂. ｘ This causes environmental pollution. With increasing environmental awareness and greater efforts in energy conservation and emission reduction, various countries are imposing increasingly stringent standards on the sulfur content of fuel oil. Alkylated oil is an ideal and clean high-octane gasoline blending component. It is generally produced by the alkylation of isoalkanes and alkenes (mainly isobutane and butene) under the action of strong acids or solid acid catalysts. It has a motor octane number of over 95% and is a non-aromatic, non-olefin, high-octane alkane blending component. China's alkylation process uses post-etherification C4 from refineries as feedstock, and zeolite molecular sieves as solid acid catalysts. These zeolite molecular sieves are easily deactivated by poisoning substances in the post-etherification C4, with sulfides being one such poison. To ensure the long-term operation of the solid acid catalyst alkylation unit, these poisons must be strictly controlled. Sulfides in refinery feedstock typically include hydrogen sulfide, COS, disulfides, thiols, thioethers, and thiophene. Currently, mature desulfurization technologies mainly include liquid-phase desulfurization, such as the Merox extraction-oxidation desulfurization alkaline washing technology developed by UOP in the United States, fiber membrane processes, fixed-bed alkali-free desulfurization processes, or adsorption methods. Among these, the alkaline washing process consumes a large amount of alkali, which can easily cause environmental pollution; the catalyst in the Merox extraction-oxidation process is prone to aggregation and deactivation, resulting in a low overall desulfurization rate; the fiber membrane desulfurization process requires a large investment and is prone to clogging by impurities; and the fixed-bed adsorption process operates at high temperatures and consumes a lot of energy.

[0003] Adsorption desulfurization technology is another commonly used method for removing organic sulfur from liquefied petroleum gas (LPG). This method uses molecular sieves, activated carbon, and metal oxides or composite metal oxides with certain adsorption capacity as adsorbents. These adsorbents utilize physical adsorption, van der Waals forces, chemical adsorption, and complexation adsorption to separate sulfides from LPG. This method is simple to operate, convenient, requires low investment, and is pollution-free. Compared with simple hydrodesulfurization, it does not cause a loss of octane number. However, existing desulfurization adsorption technologies still have problems such as low sulfur capacity, poor acid tolerance, and insufficient selectivity, making it difficult to achieve efficient desulfurization and deacidification simultaneously. Molecular sieve adsorbents have good structural strength, a large specific surface area, and high surface activity, enabling them to adsorb molecules smaller than the pore size of the molecular sieve. Manganese oxides have abundant surface oxygen vacancies and variable valence states, and have a strong adsorption capacity for acidic substances and sulfur compounds. However, single carriers have insufficient catalytic activity. Pt-Ag bimetallic combinations can promote the activation and transformation of sulfur species through synergistic effects and improve desulfurization efficiency. However, Pt and Ag are precious metals, and the preparation cost of adsorbents is high, making them unsuitable for large-scale industrial production applications.

[0004] Patent CN102895937B discloses an aluminum-silicon composite oxide as the adsorbent carrier and rare-earth cerium-modified nickel bimetal as the active component of the adsorbent. Based on the carrier mass, the mass percentage of the active component Ni-Ce is 1-30%, with a Ni / Ce molar ratio of 2-19. The desulfurization adsorbent obtained by this method was tested on a static adsorption fixed bed to selectively remove sulfur from fuel oil. At 25°C and atmospheric pressure, the Ni-Ce / Al2O3-SiO2 adsorbent achieved a desulfurization efficiency of over 90% in a single pass to remove high-sulfur Jet-A fuel from commercial fuel. However, its desulfurization depth is insufficient, failing to reach below 10 ppm.

[0005] Patent CN103041771A discloses a method for preparing an adsorbent desulfurizer by loading transition metal silver ions onto a 13X molecular sieve support via liquid-phase ion exchange, followed by calcination activation. However, this adsorbent preparation process uses silver nitrate solution, which is expensive and unsuitable for large-scale industrial applications.

[0006] Patent CN112934173B discloses a copper-cerium bimetallic modified 4A molecular sieve desulfurization adsorbent, its preparation method, and its application. This adsorbent uses copper and cerium as active components and 4A molecular sieve synthesized from kaolin as the carrier material. It exhibits excellent desulfurization performance under normal temperature and pressure conditions, minimal impact on fuel composition, maintenance of a high octane number, low investment, low operating costs, low energy consumption, and high desulfurization rate. However, chemically adsorbed sulfur (such as Na2S) is difficult to completely desorb, its sulfur capacity gradually decreases, it decomposes upon encountering strong acids, and its renewability is poor.

[0007] In summary, traditional hydrodesulfurization (HDS) requires high temperature and pressure conditions for deep desulfurization, resulting in high energy consumption, olefin saturation, and octane number loss. Alkali washing processes are prone to alkaline contamination. Ordinary molecular sieve adsorbents (such as CuY and AgX) have low adsorption capacity for thiols and cannot simultaneously deacidify. Traditional adsorbents often use single-metal or noble metal loading systems, which have drawbacks such as high cost, low sulfur capacity, and poor acid tolerance. Existing bimetallic systems (such as Pt-Ag) can simultaneously desulfurize and deacidify, but the noble metal Pt is expensive, and high-temperature calcination causes metal agglomeration (particle size >10nm), reducing the utilization rate of active sites. Although manganese oxide molecular sieves (such as OMS-2) have redox capabilities, Ag loaded by traditional impregnation methods is prone to sintering, and the sulfur capacity decreases by more than 30% after recycling.

[0008] Therefore, there is an urgent need in the market for a trace sulfide deep removal adsorbent that can remove sulfides from oil products under normal temperature and pressure conditions, while also being low in synthesis cost and easy to industrialize. Summary of the Invention

[0009] To address the problems existing in the prior art, the purpose of this invention is to obtain a bimetallic modified manganese oxide molecular sieve adsorbent that can remove sulfides from oil products under normal temperature and pressure conditions, with high desulfurization precision, high sulfur capacity, high single-pass conversion rate, low synthesis cost, and easy industrialization.

[0010] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0011] The first aspect of this invention provides a bimetallic modified manganese oxide molecular sieve adsorbent, comprising a manganese oxide support and an active component, wherein the manganese oxide support is MnO. x -ZSM-5, MnO x The mass percentage of the manganese oxide support is 10-15 wt%, x = 1.5-2.0; the active components are Co and Cu.

[0012] This application utilizes Co and Cu-modified manganese oxide molecular sieves to create an adsorbent with abundant surface oxygen vacancies and acidic sites, exhibiting adsorption advantages for acidic substances and sulfur species. The molecular sieve, acting as a structural platform, prevents the sintering and agglomeration of the active metal components. By sieving molecules through pore size, it enhances selectivity and provides mechanical strength and thermal stability. Co and Cu are low-cost metals, and Co's variable valence state (Co... 2+ / Co 3+ Cu can enhance the oxidative activation of sulfur species. + / Cu 2 +It can stably adsorb compounds such as thiols and thioethers through coordination, and the synergistic effect of the two with manganese oxides can significantly improve the desulfurization and deacidification efficiency, solving the problem of difficulty in balancing economy and performance in existing technologies.

[0013] A second aspect of this invention provides a method for preparing a bimetallic modified manganese oxide molecular sieve adsorbent, comprising the following steps:

[0014] (1) Take ZSM-5 molecular sieve and add it to an aqueous solution containing 0.05-0.20 mol / L of oxidized or reduced manganese compound for ultrasonic impregnation. The solid-liquid ratio is 1 g / (3-5) ml. After centrifugation, drying and calcination, MnO is obtained. x -ZSM-5 carrier;

[0015] (2) The MnO obtained in step (1) is impregnated using a co-impregnation method. x -ZSM-5 carrier was added to a mixed solution to load Co and Cu, with a solid-liquid ratio of 1 g / (7-10) ml. After centrifugation, drying, pretreatment and reduction, a bimetallic modified manganese oxide molecular sieve adsorbent was obtained.

[0016] This application utilizes Co and Cu-modified manganese oxide molecular sieves to reduce the Co and MnO content in the prepared adsorbent. x Formation of redox pairs (Co 3+ / Co 2+ -Mn 4+ / Mn 3+ This forms a highly efficient electron transfer channel, significantly enhancing the oxidative activation ability of sulfides and converting them into forms that are easier to adsorb or remove. Cu strengthens sulfur adsorption through Cu-S bonds, while Cu oxides act as alkaline sites to neutralize acidic substances such as naphthenic acids in oils, achieving simultaneous deacidification. + / Cu 2+ It can stably adsorb compounds such as thiols and thioethers through coordination; the synergistic effect of Co and Cu with manganese oxides can significantly improve the desulfurization and deacidification efficiency of the adsorbent, and the cost of Co and Cu is only 2%-3% of that of Pt-Ag combination, solving the problem of difficulty in balancing economy and performance in existing technologies.

[0017] In some embodiments, the silicon-to-aluminum ratio of the ZSM-5 molecular sieve is 20-50.

[0018] In some embodiments, the oxidized manganese compound is selected from one or more of potassium manganate, potassium permanganate, and sodium permanganate.

[0019] In some embodiments, the reduced manganese compound is selected from one or more of manganese nitrate, manganese sulfate, manganese chloride, and manganese acetate.

[0020] In some embodiments, the ultrasonic impregnation time in step (1) is 3-5 hours, the drying temperature is 80-100°C and the time is 6-10 hours, and the calcination temperature is 450-900°C and the time is 4-6 hours.

[0021] In some embodiments, the mixed solution contains Co 2+ With Cu 2+ The molar ratio is 1:(1-3).

[0022] Preferably, the Co 2+ Derived from cobalt nitrate; the Cu 2+ It is derived from copper nitrate.

[0023] In some embodiments, the stirring and impregnation time of the co-impregnation method in step (2) is 2-4 h; the drying temperature is 80-90 °C and the time is 8-12 h; the pretreatment conditions are pretreatment at 200-250 °C for 2-3 h in a nitrogen atmosphere; the reduction conditions are reduction at a hydrogen-nitrogen mixed atmosphere for 3-4 h, the volume ratio of hydrogen to nitrogen is 1:(7-9), and the temperature is 300-350 °C.

[0024] The third aspect of this invention provides an application of a bimetallic modified manganese oxide molecular sieve adsorbent, suitable for use at temperatures of 20-100°C, atmospheric pressure, and volume hourly space velocity (VHSV) of 2.0-10 h⁻¹. -1 Processing oil products under certain conditions.

[0025] In some embodiments, the oil contains sulfur-containing compounds, including one or more of methanethiol, 2-methylbutanethiol, dimethyl disulfide, dibutyl sulfate, carbophenylpropiophene, and butyl hydrogen sulfate.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) The bimetallic modified manganese oxide molecular sieve adsorbent prepared by the present invention can remove sulfides from oil under normal temperature and pressure conditions. It has high desulfurization precision, high sulfur capacity, and high single-pass conversion rate. At the same time, the synthesis cost is low and it is easy to industrialize.

[0028] (2) The adsorbent prepared by the present invention using Co and Cu modified manganese oxide molecular sieves contains Co and MnO x The formation of redox pairs promotes the oxidation and activation of sulfur species. Cu achieves stable adsorption of compounds such as thiols and thioethers through strong adsorption, coordination and acid-base regulation. Furthermore, the synergistic effect of Co and Cu with manganese oxides can significantly improve desulfurization and deacidification efficiency, solving the problem of balancing economy and performance in existing technologies.

[0029] (3) By selecting manganese oxide molecular sieves, the adsorbent prepared in this invention has abundant surface oxygen vacancies and acidic sites, which improves the adsorption capacity and acid resistance of the adsorbent for acidic substances and sulfur species. The adsorbent retains ≥88% of its activity after 10 cycles of use and recovers ≥90% of its performance after regeneration. Detailed Implementation

[0030] The present invention will be described below with reference to specific embodiments. It should be noted that the following embodiments are examples of the present invention and are used only to illustrate the invention, not to limit it. Other combinations and various modifications within the scope of the present invention can be made without departing from its spirit or scope.

[0031] In the following examples and comparative examples, the compounds and related reagents and raw materials used were all commercially available. The silica-alumina ratio of the ZSM-5 molecular sieve was 30.

[0032] Example 1

[0033] A bimetallic modified manganese oxide molecular sieve adsorbent includes a manganese oxide support and an active component, wherein the manganese oxide support is MnO2-ZSM-5, and the mass percentage of MnO2 in the manganese oxide support is 12wt%; the active component is Co and Cu.

[0034] The preparation method of the bimetallic modified manganese oxide molecular sieve adsorbent in this embodiment includes the following steps:

[0035] (1) Take 10g of ZSM-5 molecular sieve and add it to 50ml of 0.10mol / L manganese nitrate aqueous solution for ultrasonic impregnation for 4h, centrifuge, dry at 90℃ for 8h, and calcine in air at 500℃ for 5h to obtain MnO2-ZSM-5 support;

[0036] (2) Using the co-impregnation method, 10g of the MnO2-ZSM-5 support obtained in step (1) was added to 85ml of a mixed aqueous solution containing 0.02mol / L cobalt nitrate and 0.05mol / L copper nitrate and stirred for 3h. After centrifugation, drying at 85℃ for 10h, pretreatment in a nitrogen atmosphere at 220℃ for 2.5h and reduction in a hydrogen-nitrogen mixed atmosphere at 320℃ for 3.5h, with a hydrogen to nitrogen volume ratio of 1:8, a bimetallic modified manganese oxide molecular sieve adsorbent was obtained.

[0037] Example 2

[0038] A bimetallic modified manganese oxide molecular sieve adsorbent includes a manganese oxide support and an active component, wherein the manganese oxide support is MnO2-ZSM-5, and the mass percentage of MnO2 in the manganese oxide support is 12wt%; the active component is Co and Cu.

[0039] The preparation method of the bimetallic modified manganese oxide molecular sieve adsorbent in this embodiment includes the following steps:

[0040] (1) Take 10g of ZSM-5 molecular sieve and add it to 50ml of 0.10mol / L manganese nitrate aqueous solution for ultrasonic impregnation for 5h, centrifuge, dry at 80℃ for 10h, and calcine in air at 450℃ for 6h to obtain MnO2-ZSM-5 support;

[0041] (2) Using the co-impregnation method, 10g of the MnO2-ZSM-5 support obtained in step (1) was added to 70ml of a mixed aqueous solution containing 0.02mol / L cobalt nitrate and 0.02mol / L copper nitrate and stirred for 2h. After centrifugation, drying at 80℃ for 12h, pretreatment in a nitrogen atmosphere at 200℃ for 3h and reduction in a hydrogen-nitrogen mixed atmosphere at 300℃ for 4h, with a hydrogen to nitrogen volume ratio of 1:7, a bimetallic modified manganese oxide molecular sieve adsorbent was obtained.

[0042] Example 3

[0043] A bimetallic modified manganese oxide molecular sieve adsorbent includes a manganese oxide support and an active component, wherein the manganese oxide support is MnO2-ZSM-5, and the mass percentage of MnO2 in the manganese oxide support is 12wt%; the active component is Co and Cu.

[0044] The preparation method of the bimetallic modified manganese oxide molecular sieve adsorbent in this embodiment includes the following steps:

[0045] (1) Take 10g of ZSM-5 molecular sieve and add it to 50ml of 0.10mol / L manganese nitrate aqueous solution for ultrasonic impregnation for 3h, centrifuge, dry at 100℃ for 6h, and calcine in air at 900℃ for 4h to obtain MnO2-ZSM-5 support;

[0046] (2) Using the co-impregnation method, 10g of the MnO2-ZSM-5 support obtained in step (1) was added to 100ml of a mixed aqueous solution containing 0.02mol / L cobalt nitrate and 0.06mol / L copper nitrate and stirred for 4h. After centrifugation, drying at 90℃ for 8h, pretreatment in a nitrogen atmosphere at 250℃ for 2h and reduction in a hydrogen-nitrogen mixed atmosphere at 350℃ for 3h, with a hydrogen to nitrogen volume ratio of 1:9, a bimetallic modified manganese oxide molecular sieve adsorbent was obtained.

[0047] Example 4

[0048] A bimetallic modified manganese oxide molecular sieve adsorbent and its preparation method are disclosed. The specific implementation method is the same as in Example 1, except that the Cu content in the mixed solution is 0.1 mol / L.

[0049] Comparative Example 1

[0050] A bimetallic modified manganese oxide molecular sieve adsorbent includes a manganese oxide support and an active component, wherein the manganese oxide support is MnO2-ZSM-5; the mass percentage of MnO2 in the manganese oxide support is 25wt%; and the active component is Co and Cu.

[0051] The preparation method of the bimetallic modified manganese oxide molecular sieve adsorbent in this embodiment includes the following steps:

[0052] (1) Take 10g of ZSM-5 molecular sieve and add it to 50ml of 0.30mol / L manganese nitrate aqueous solution for ultrasonic impregnation for 4h, centrifuge, dry at 90℃ for 8h, and calcine in air at 500℃ for 5h to obtain MnO2-ZSM-5 support;

[0053] (2) Using the co-impregnation method, 10g of the MnO2-ZSM-5 support obtained in step (1) was added to 85ml of a mixed aqueous solution containing 0.02mol / L cobalt nitrate and 0.05mol / L copper nitrate and stirred for 3h. After centrifugation, drying at 85℃ for 10h, pretreatment in a nitrogen atmosphere at 220℃ for 2.5h and reduction in a hydrogen-nitrogen mixed atmosphere at 320℃ for 3.5h, with a hydrogen to nitrogen volume ratio of 1:8, a bimetallic modified manganese oxide molecular sieve adsorbent was obtained.

[0054] Comparative Example 2

[0055] A metal-modified manganese oxide molecular sieve adsorbent includes a manganese oxide support and an active component, wherein the manganese oxide support is MnO2-ZSM-5, the mass percentage of MnO2 in the manganese oxide support is 12wt%, and the active component is Co.

[0056] The preparation method of the metal-modified manganese oxide molecular sieve adsorbent in this embodiment includes the following steps:

[0057] (1) Take 10g of ZSM-5 molecular sieve and add it to 50ml of 0.10mol / L manganese nitrate aqueous solution for ultrasonic impregnation for 4h, centrifuge, dry at 90℃ for 8h, and calcine in air at 500℃ for 5h to obtain MnO2-ZSM-5 support;

[0058] (2) Using the co-impregnation method, 10g of the MnO2-ZSM-5 support obtained in step (1) was added to 85ml of an aqueous solution containing 0.02mol / L cobalt nitrate and stirred for 3h. After centrifugation, drying at 85℃ for 10h, pretreatment in a nitrogen atmosphere at 220℃ for 2.5h and reduction in a hydrogen-nitrogen mixed atmosphere at 320℃ for 3.5h, with a hydrogen to nitrogen volume ratio of 1:8, metal-modified manganese oxide molecular sieve adsorbent was obtained.

[0059] Comparative Example 3

[0060] A metal-modified manganese oxide molecular sieve adsorbent includes a manganese oxide support and an active component, wherein the manganese oxide support is MnO2-ZSM-5, the mass percentage of MnO2 in the manganese oxide support is 12wt%, and the active component is Cu.

[0061] The preparation method of the metal-modified manganese oxide molecular sieve adsorbent in this embodiment includes the following steps:

[0062] (1) Take 10g of ZSM-5 molecular sieve and add it to 50ml of 0.10mol / L manganese nitrate aqueous solution for ultrasonic impregnation for 4h, centrifuge, dry at 90℃ for 8h, and calcine in air at 500℃ for 5h to obtain MnO2-ZSM-5 support;

[0063] (2) Using the co-impregnation method, 10g of the MnO2-ZSM-5 support obtained in step (1) was added to 85ml of an aqueous solution containing 0.05mol / L copper nitrate and stirred for 3h. After centrifugation, drying at 85℃ for 10h, pretreatment in a nitrogen atmosphere at 220℃ for 2.5h and reduction in a hydrogen-nitrogen mixed atmosphere at 320℃ for 3.5h, with a hydrogen to nitrogen volume ratio of 1:8, metal-modified manganese oxide molecular sieve adsorbent was obtained.

[0064] Performance testing

[0065] The bimetallic modified manganese oxide molecular sieve adsorbents obtained in the above embodiments and comparative examples were tested:

[0066] DBT adsorption experiment: 1 ml of dibenzothiophene with a sulfur content of 200 ppmw was added to a sealed glass container. Octane-based simulated oil was used, with 100 mg of adsorbent dispersed in the simulated oil. The adsorption reaction was allowed to proceed under static conditions at room temperature and pressure. Samples were taken after 24 hours (assuming adsorption equilibrium was achieved), and the adsorption was analyzed using a GC-MS system. The FPD gas chromatograph was used to detect the content of dibenzothiophene in the simulated oil and to calculate the removal rate of the adsorbent.

[0067] Adsorption-regeneration experiment: The adsorbent, after adsorption, was centrifuged with simulated oil and transferred to a crucible. The crucible was placed in a muffle furnace and heated to 450°C at a rate of 5°C / min under air atmosphere, and held at that temperature for 2 hours. The mixture was then cooled to room temperature in a dry environment. DBT adsorption experiments were performed again, and the removal rate and performance recovery rate of the regenerated adsorbent were calculated. This process was repeated 10 times, and the removal rate and activity retention rate of the adsorbent after 10 cycles were calculated.

[0068] Performance recovery rate after regeneration = (Q1 / Q0) × 100%; Q0 is the initial adsorption capacity; Q1 is the adsorption capacity after the first regeneration;

[0069] Activity retention rate after 10 cycles = (Q 10 / Q0)×100%; Q0 is the initial adsorption capacity; Q 10 This represents the adsorption capacity after the 10th regeneration.

[0070] The test results are shown in Table 1:

[0071] Table 1

[0072]

[0073] As shown in Table 1, the bimetallic modified manganese oxide molecular sieve adsorbents of Examples 1-3 of this application have high desulfurization rates. After 10 cycles of use, the activity retention rate of the adsorbent is ≥88%, and the performance recovery rate after regeneration is ≥90%, indicating that the adsorbent has excellent durability. The comparison between Example 4 and Example 1 shows that changing the Cu loading will reduce the synergistic effect of each component, thereby reducing the desulfurization rate and durability of the adsorbent. The comparison between Comparative Example 1 and Example 1 shows that changing the content of reduced manganese compounds may increase the amount of MnO2 generated on the MnO2-ZSM-5 support, thereby blocking the pores on the ZSM-5 molecular sieve and reducing the desulfurization rate and durability of the adsorbent. The comparison between Comparative Examples 2 and 3 and Example 1 shows that the adsorbent without Co or Cu loading has a lower desulfurization rate and poorer durability.

[0074] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A bimetallic modified manganese oxide molecular sieve adsorbent, comprising a manganese oxide support and an active component, characterized in that: The manganese oxide support is MnO. x -ZSM-5, MnO x The mass percentage of the manganese oxide support is 10-15 wt%, x = 1.5-2.0; the active components are Co and Cu. The preparation method of the bimetallic modified manganese oxide molecular sieve adsorbent includes the following steps: (1) Take ZSM-5 molecular sieve and add it to an aqueous solution containing 0.05-0.20 mol / L of oxidized or reduced manganese compound for ultrasonic impregnation. The solid-liquid ratio is 1 g / (3-5) ml. After centrifugation, drying and calcination, MnO is obtained. x -ZSM-5 carrier; (2) The MnO obtained in step (1) is impregnated using a co-impregnation method. x -ZSM-5 carrier was added to a mixed solution to load Co and Cu, with a solid-liquid ratio of 1g / (7-10)ml. After centrifugation, drying, pretreatment and reduction, a bimetallic modified manganese oxide molecular sieve adsorbent was obtained. Co²⁻ in the mixed solution + With Cu² + The molar ratio is 1:(1-3); The ultrasonic impregnation time in step (1) is 3-5 hours, the drying temperature is 80-100℃ and the time is 6-10 hours, and the calcination temperature is 450-900℃ and the time is 4-6 hours. The stirring and impregnation time for the co-impregnation method described in step (2) is 2-4 h; the drying temperature is 80-90℃ and the time is 8-12 h; the pretreatment conditions are 200-250℃ in a nitrogen atmosphere for 2-3 h; the reduction conditions are 3-4 h in a hydrogen-nitrogen mixed atmosphere, with a hydrogen to nitrogen volume ratio of 1:(7-9) and a temperature of 300-350℃.

2. A method for preparing the bimetallic modified manganese oxide molecular sieve adsorbent according to claim 1, characterized in that, Includes the following steps: (1) Take ZSM-5 molecular sieve and add it to an aqueous solution containing 0.05-0.20 mol / L of oxidized or reduced manganese compound for ultrasonic impregnation. The solid-liquid ratio is 1 g / (3-5) ml. After centrifugation, drying and calcination, MnO is obtained. x -ZSM-5 carrier; (2) The MnO obtained in step (1) is impregnated using a co-impregnation method. x -ZSM-5 carrier was added to a mixed solution to load Co and Cu, with a solid-liquid ratio of 1g / (7-10)ml. After centrifugation, drying, pretreatment and reduction, a bimetallic modified manganese oxide molecular sieve adsorbent was obtained. Co²⁻ in the mixed solution + With Cu² + The molar ratio is 1:(1-3); The ultrasonic impregnation time in step (1) is 3-5 hours, the drying temperature is 80-100℃ and the time is 6-10 hours, and the calcination temperature is 450-900℃ and the time is 4-6 hours. The stirring and impregnation time for the co-impregnation method described in step (2) is 2-4 h; the drying temperature is 80-90℃ and the time is 8-12 h; the pretreatment conditions are 200-250℃ in a nitrogen atmosphere for 2-3 h; the reduction conditions are 3-4 h in a hydrogen-nitrogen mixed atmosphere, with a hydrogen to nitrogen volume ratio of 1:(7-9) and a temperature of 300-350℃.

3. The preparation method of the bimetallic modified manganese oxide molecular sieve adsorbent according to claim 2, characterized in that, The silicon-aluminum ratio of the ZSM-5 molecular sieve is 20-50.

4. The preparation method of the bimetallic modified manganese oxide molecular sieve adsorbent according to claim 2, characterized in that, The oxidized manganese compound is selected from one or more of potassium manganate, potassium permanganate, and sodium permanganate.

5. The preparation method of the bimetallic modified manganese oxide molecular sieve adsorbent according to claim 2, characterized in that, The reduced manganese compound is selected from one or more of manganese nitrate, manganese sulfate, manganese chloride, and manganese acetate.

6. The application of the bimetallic modified manganese oxide molecular sieve adsorbent according to claim 1 or the bimetallic modified manganese oxide molecular sieve adsorbent obtained by the preparation method according to any one of claims 2-5, characterized in that, At a temperature of 20-100℃, a pressure of atmospheric pressure, and a volumetric hourly space velocity of 2.0-10 h⁻¹ - ¹ Process oil products under the following conditions.

7. The application of the bimetallic modified manganese oxide molecular sieve adsorbent according to claim 6, characterized in that, The oil contains sulfur-containing compounds, including one or more of methanethiol, 2-methylbutanethiol, dimethyl disulfide, dibutyl sulfate, carbophenylpropiophene, and butyl hydrogen sulfate.

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