A molding method for a copper-based desulfurization adsorbent for ultra-deep thiophene removal

Abstract

This invention relates to a molding method for a copper-based desulfurization adsorbent for ultra-deep thiophene removal. The method involves uniformly mixing the copper-based desulfurization adsorbent with 30-60% (by mass) of a binder and 1-10% (by mass) of an extrusion aid, adding a silica sol nitric acid aqueous solution, kneading to obtain a wet material, extruding it into shape using an extruder, aging and drying it at room temperature, and calcining it at 350-550℃ for 3-8 hours to obtain the molded desulfurization adsorbent. The binder is a mixture of boehmite and kaolin in a mass ratio of 1:(1-3), and the extrusion aid is guar gum powder. This invention ensures that the prepared molded desulfurization adsorbent meets the mechanical strength requirements for industrial applications while exhibiting excellent desulfurization performance.

Description

Technical Field

[0001] This invention belongs to the field of coke oven gas purification technology, and relates to a method for forming a desulfurization adsorbent, particularly a method for forming a copper-based desulfurization adsorbent for ultra-deep removal of thiophene. Background Technology

[0002] Coke oven gas is one of the main byproducts of the coking industry, producing 400 cubic meters of gas per ton of coke produced. 3 The remaining portion is coke oven gas. Using coke oven gas as a raw material to produce natural gas is one of the important ways to efficiently utilize coke oven gas.

[0003] However, the sulfides in coke oven gas can poison the nickel-based catalysts for methanation, shortening their lifespan. Therefore, most of the sulfides in coke oven gas need to be removed through coarse and fine desulfurization. Current industrial production typically employs a process of iron-molybdenum pre-hydrogenation + cobalt-molybdenum primary hydrogenation + zinc oxide adsorption + nickel-molybdenum secondary hydrogenation + zinc oxide adsorption to remove COS, CS2, mercaptans, sulfides, and H2S from coke oven gas. However, thiophene at the ppm level still exists. Therefore, an ultra-deep desulfurization adsorption tower must be used after the above desulfurization process to remove the remaining thiophene to the ppb level to meet the requirements for methanation catalyst use.

[0004] CN112138625A discloses an adsorption desulfurizer for ultra-deep removal of thiophene from coke oven gas and its preparation method. It introduces Al2O3 as a support and NiO and ZrO2 as additives into a Cu / ZnO base to improve the mechanical strength and increase the pore structure of the adsorption desulfurizer. Through the synergistic effect of the metal additives on copper and zinc, the surface area of ​​the adsorption desulfurizer is increased, enhancing its activity and further improving desulfurization efficiency. However, the utilization rate of the active components copper and zinc in this adsorption desulfurizer is only about 30%, and the amount of the precious metal zirconium is relatively large, resulting in problems such as low sulfur capacity, low activity, and high preparation cost.

[0005] CN115254006A discloses a desulfurization adsorbent for ultra-deep removal of thiophene from coke oven gas and its preparation method. It selects boehmite as the alumina carrier and, by adjusting the content and ratio of the carrier and the metal additive zirconium oxide, increases the alumina content by 10-20% and reduces the zirconium oxide content, thereby improving the desulfurization performance of the adsorbent and achieving ultra-deep removal of thiophene from coke oven gas, with a penetration sulfur capacity of not less than 39 mg / g.

[0006] Although the desulfurization effect of this desulfurization adsorbent meets the requirements, considering that the adsorbent is in powder form, if it is directly applied to industrial production, there will be serious problems such as a sharp increase in equipment resistance, deterioration of mass and heat transfer, and loss of powder adsorbent with the bed airflow, which restricts its practical application in industry. Therefore, it is necessary to consider shaping the adsorbent to obtain a catalyst with a certain shape and mechanical strength in order to reduce bed pressure drop, improve mass and heat transfer, and increase the diffusion rate of reactants.

[0007] However, copper-based adsorbents are brittle materials with poor powder particle flowability, making molding difficult. Rotational molding suffers from defects such as uneven diameter, rough surface, and low mechanical strength. Compression molding, due to the small required adsorbent diameter, is difficult to produce, with low success rates and high costs. Spray drying molding consumes a lot of electricity, has low thermal efficiency, generates significant dust during production, and results in inconsistent product particle size and complex, difficult-to-control production processes. Extrusion molding is simple to operate and has a high output, making it the most commonly used molding method in industry. However, the addition of binders during molding can easily reduce the mechanical strength and desulfurization performance of the adsorbent. Therefore, it is necessary to obtain a molded adsorbent with high mechanical strength while maintaining its original desulfurization performance to the greatest extent possible.

[0008] CN114768885A discloses a method for extruding an acetophenone hydrogenation catalyst. The method involves kneading catalyst powder, silica sol, deionized water, extrusion aid, and pore-expanding agent into a plastic body in a specific ratio, followed by extrusion, drying, and calcination to prepare a strip-shaped catalyst. The addition of the pore-expanding agent significantly improves the catalyst's pore structure, reduces diffusion within the pores, and extends catalyst lifespan. However, the catalyst powder has already undergone one calcination treatment, and the subsequent calcination after molding complicates the preparation and molding process of the adsorbent and increases costs.

[0009] CN112705168A discloses a method for molding ultraporous MOF adsorbent materials. By adjusting the type and ratio of binder, spherical MOF material particles meeting industrial requirements are obtained. In this method, polyvinyl alcohol and methyl cellulose are used to mold ZIF-7 powder, resulting in ZIF-7 spherical particles with a high loading rate. Although the spherical particles achieve high mechanical strength, the adsorption capacity is only maintained at 89% of the original powder. The addition of binder during the molding process reduces the performance of the original powder.

[0010] Therefore, if a desulfurization adsorbent with high adsorption capacity can be obtained, and an adsorbent with high mechanical strength can be obtained while maintaining or improving its desulfurization performance, it will be of great significance for the application of desulfurization adsorbents in the ultra-deep desulfurization of coke oven gas in industrial production. Summary of the Invention

[0011] The purpose of this invention is to provide a molding method for a copper-based desulfurization adsorbent for ultra-deep thiophene removal, so as to solve the problems of low mechanical strength and significant decrease in desulfurization performance during the molding process of powdered adsorbents.

[0012] To achieve the above-mentioned objectives, this invention provides a molding method for a copper-based desulfurization adsorbent for ultra-deep thiophene removal. The method involves using a copper-based desulfurization adsorbent precursor as raw material, mixing it evenly with 30-60% by weight of a binder and 1-10% by weight of an extrusion aid, adding a silica sol nitric acid aqueous solution, kneading to obtain a wet material, extruding it using an extruder, aging and drying it at room temperature, and calcining it at 350-550℃ for 3-8 hours to obtain the molded desulfurization adsorbent.

[0013] The copper-based desulfurization adsorbent precursor is a precursor powder prepared according to the method disclosed in CN115254006A, specifically comprising:

[0014] 1) Weigh out 5-25 parts by weight of copper nitrate trihydrate, 6-30 parts by weight of zinc nitrate hexahydrate, 5-20 parts by weight of boehmite, 0.1-2 parts by weight of nickel nitrate hexahydrate, and 0.1-5 parts by weight of zirconium nitrate pentahydrate, and dissolve them evenly in deionized water to obtain the first solution;

[0015] 2) Weigh 10-40 parts of anhydrous sodium carbonate and dissolve it evenly in deionized water to obtain a second solution;

[0016] 3) Mix the first solution and the second solution at 40–90°C to carry out a co-precipitation reaction;

[0017] 4) The coprecipitation reaction product is aged at 30-90℃ for 1-5 hours, washed and dried to obtain the copper-based desulfurization adsorbent precursor.

[0018] Furthermore, the binder is a mixture of boehmite and kaolin in a mass ratio of 1:(1-3), and the extrusion aid is guar gum powder.

[0019] The molding method described in this invention enables the preparation of molded copper-based desulfurization adsorbents with high mechanical strength while maintaining the desulfurization performance of the copper-based desulfurization adsorbent powder prepared in the original CN115254006A.

[0020] Furthermore, in the molding method of the present invention, the concentration of the silica sol nitric acid aqueous solution used is preferably 20-50%, and the amount used is preferably 30-60% of the mass of the copper-based desulfurization adsorbent precursor.

[0021] Furthermore, the present invention obtains the silica sol nitric acid aqueous solution by adding an appropriate amount of concentrated nitric acid as a solvent to the silica sol. The amount of concentrated nitric acid added is preferably 2 to 15% of the mass of the copper-based desulfurization adsorbent precursor.

[0022] Specifically, the present invention preferably involves kneading the silica sol nitric acid aqueous solution for 10 to 30 minutes after adding it to obtain a uniformly mixed wet material.

[0023] More specifically, the present invention uses a cylindrical forming die with a diameter of 1 to 4 mm to extrude the wet material, and the extruder frequency and speed during extrusion are preferably 10 to 30 r / min.

[0024] Furthermore, this invention requires that the extruded strips of wet material with a diameter of 1-5 mm be aged in air at room temperature for at least 4 hours before being dried. Preferred drying conditions are drying at 100-150°C for 10-15 hours.

[0025] Tests showed that the mechanical strength of the molded desulfurization adsorbent prepared using the molding method of this invention reached 64 N / cm. When it was packed into a fixed-bed reactor and reduced at 200°C for 3 hours under a hydrogen atmosphere, a simulated coke oven gas (58% H2, 26% CH4, 8% CO, 3% CO2, 4% N2, 1% O2) mixed with 300 ppmv thiophene was introduced to carry out the desulfurization adsorption reaction. The breakthrough sulfur capacity of the molded desulfurization adsorbent was not less than 20 mg / g.

[0026] The optimal breakthrough adsorption capacity of the powdered desulfurization adsorbent prepared in CN115254006A is 39.46 mg / g. Based on the copper-based desulfurization adsorbent precursor of CN115254006A, this invention prepares a molded desulfurization adsorbent by adding binders and other molding aids in an approximately 1:1 ratio. The effective component accounts for about 50% of the total mass of the molded desulfurization adsorbent. Therefore, based on the effective component, the breakthrough adsorption capacity of the molded desulfurization adsorbent of this invention should be no less than 40 mg / g, or even slightly higher than the breakthrough adsorption capacity of the powdered desulfurization adsorbent of CN115254006A. The molded desulfurization adsorbent prepared by this invention improves mechanical strength without causing a decrease in the desulfurization performance of the desulfurization adsorbent.

[0027] This invention uses copper-based desulfurization adsorbent precursors as raw materials to prepare molded desulfurization adsorbents. Because the precursors themselves have a certain degree of binding property, the amount of binder used during the molding process can be reduced. The molded desulfurization adsorbent not only has a higher effective utilization rate of the active components but also maintains its mechanical strength. During the calcination process, the binders and extrusion aids used in molding produce a small amount of CO2 and H2O, which escapes, leaving more micropores. This increases the pore structure and specific surface area of ​​the molded desulfurization adsorbent, improving the distribution capacity of the active components and further providing more active sites for the reactive adsorption of thiophene, thus increasing its desulfurization activity.

[0028] The entire preparation process of the molded desulfurization adsorbent of this invention only requires one calcination treatment, which has little impact on the desulfurization performance and mechanical strength of the molded desulfurization adsorbent. Moreover, the preparation process is simple and the cost is reduced.

[0029] The pseudoboehmite used in the molding process of this invention serves two purposes: firstly, as a binder to improve the mechanical strength of the molded desulfurization adsorbent; and secondly, as a dispersant to ensure uniform dispersion and higher utilization of the adsorbent, thereby increasing its specific surface area and pore volume, and ultimately improving its sulfur capacity. Kaolin, on the other hand, primarily acts as a binder, filling a significant portion of the material's voids. After calcination, it is less prone to volatilization and decomposition, resulting in a stronger final molded desulfurization adsorbent. Using kaolin as a composite binder in this invention, its appropriate addition ratio can not only maintain or improve the sulfur capacity of the desulfurization adsorbent but also enhance its strength. Attached Figure Description

[0030] Figure 1 The amount of thiophene that is adsorbed through by the desulfurization adsorbents prepared in each embodiment and comparative example in coke oven gas.

[0031] Figure 2 It refers to the mechanical strength of the desulfurization adsorbents prepared in each embodiment and comparative example. Implementation

[0032] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solutions of the present invention, so that those skilled in the art can better understand and utilize the present invention, and are not intended to limit the scope of protection of the present invention.

[0033] Unless otherwise specified, the production processes, experimental methods, or testing methods involved in the embodiments and comparative examples of this invention are all conventional methods in the prior art, and their names and / or abbreviations are all conventional names in the art, which are very clear and distinct in the relevant application fields. Those skilled in the art can understand the conventional process steps based on the names and apply the corresponding equipment, and implement them according to conventional conditions or conditions recommended by the manufacturer.

[0034] The various instruments, equipment, raw materials or reagents used in the embodiments of this invention are not subject to any special restrictions on their source. They are all conventional products that can be purchased through regular commercial channels and can be prepared according to conventional methods known to those skilled in the art. Example

[0035] Example 1

[0036] Weigh 7.25g of copper nitrate trihydrate, 8.93g of zinc nitrate hexahydrate, 3.74g of boehmite, 0.40g of nickel nitrate hexahydrate, and 0.32g of zirconium nitrate pentahydrate, add them to 200mL of deionized water, and dissolve them evenly to obtain the first solution.

[0037] Add 11.13g of anhydrous sodium carbonate to 350mL of deionized water and dissolve until homogeneous to obtain the second solution.

[0038] The two solutions were simultaneously added dropwise to a stirred reaction vessel, and a coprecipitation reaction was carried out at 70°C. The dropping rate of the first solution was 10 ml / min, and the dropping rate of the second solution was 15 ml / min. The pH of the coprecipitation reaction was adjusted to 7.5.

[0039] The coprecipitation reaction product was aged at 80℃ for 3 hours, filtered, and the filter cake was washed with deionized water 3 to 5 times. It was then dried in an oven at 110℃ for 12 hours to obtain the copper-based desulfurization adsorbent precursor.

[0040] Weigh 200g of copper-based desulfurization adsorbent precursor, 10g of guar gum powder, 33.3g of pseudoboehmite and 66.7g of kaolin and add them to a mixing device. Stir for 15 minutes to mix them evenly.

[0041] Weigh 85.5g of 30% silica sol, 6g of concentrated nitric acid and 120g of deionized water, and slowly add them to the mixing device in sequence. Mix for 15 minutes to obtain a uniform wet material.

[0042] The wet material was quickly transferred to an extruder with a 2mm round hole die and extruded into strips at a speed of 18r / min. After aging in air at room temperature for 6 hours, it was placed in an oven at 110℃ for 12 hours and then placed in a muffle furnace and calcined in air at a heating rate of 2℃ / min to 350℃ for 4.5 hours to prepare the shaped desulfurization adsorbent, denoted as PA1.

[0043] 6g of PA1 was weighed and packed into a fixed-bed reactor with an inner diameter of 18mm. The reactor was heated to 200℃ and reduced for 3 hours under a hydrogen atmosphere. Maintaining the reaction temperature at 200℃, a certain amount of simulated coke oven gas (composition: 58% H2, 26% CH4, 8% CO, 3% CO2, 4% N2, 1% O2) was introduced into the fixed-bed reactor. 300ppmv of thiophene was then mixed into the simulated coke oven gas to carry out a desulfurization adsorption reaction. The change in thiophene content at the outlet of the fixed-bed reactor was detected using gas chromatography. The calculation results are as follows: Figure 1 PA1 in the sample has a sulfur penetration capacity of 20.33 mg / g.

[0044] The compressive strength of the molded desulfurization adsorbent was determined using a particle strength tester. The molded desulfurization adsorbent was cut into 5mm long particles, and 20 particles were randomly selected to measure their mechanical strength. The maximum and minimum values ​​were removed, and the average value was calculated to obtain the mechanical strength result. Figure 2 PA1 in the sample has a mechanical strength of 64.1 N / cm.

[0045] Example 2

[0046] Weigh out 8.25g of copper nitrate trihydrate, 9.93g of zinc nitrate hexahydrate, 3.74g of boehmite, 0.40g of nickel nitrate hexahydrate, and 0.35g of zirconium nitrate pentahydrate, add them to 200mL of deionized water, and dissolve them evenly to obtain the first solution.

[0047] Add 11.13g of anhydrous sodium carbonate to 300mL of deionized water and dissolve until homogeneous to obtain the second solution.

[0048] The two solutions were simultaneously added dropwise to a stirred reaction vessel, and a coprecipitation reaction was carried out at 60°C. The dropping rate of the first solution was 10 ml / min, and the dropping rate of the second solution was 15 ml / min. The pH of the coprecipitation reaction was adjusted to 7.5.

[0049] The coprecipitation reaction product was aged at 80℃ for 2 hours, filtered, and the filter cake was washed with deionized water 3 to 5 times. It was then dried in an oven at 100℃ for 12 hours to obtain the copper-based desulfurization adsorbent precursor.

[0050] Weigh 200g of copper-based desulfurization adsorbent precursor, 10g of guar gum powder, 25g of boehmite and 75g of kaolin and add them to a mixing device. Stir for 15 minutes to mix them evenly.

[0051] Weigh 85.5g of 30% silica sol, 6g of concentrated nitric acid and 120g of deionized water, and slowly add them to the mixing device in sequence. Mix for 15 minutes to obtain a uniform wet material.

[0052] The wet material was quickly transferred to an extruder with a 2mm round hole die and extruded into strips at a speed of 18r / min. After aging in air at room temperature for 6 hours, it was placed in an oven at 120℃ for 12 hours and then placed in a muffle furnace and calcined in air at a heating rate of 3℃ / min to 400℃ for 6 hours to prepare the shaped desulfurization adsorbent, denoted as PA2.

[0053] The desulfurization performance and mechanical strength of PA2 were tested according to the method in Example 1, and the results are as follows: Figure 1 and Figure 2 As shown in PA2, its sulfur penetration capacity is 19.64 mg / g and its mechanical strength is 52.24 N / cm.

[0054] Example 3

[0055] Weigh 12.08g of copper nitrate trihydrate, 14.88g of zinc nitrate hexahydrate, 6.74g of boehmite, 0.67g of nickel nitrate hexahydrate, and 0.53g of zirconium nitrate pentahydrate, add them to 200mL of deionized water, and dissolve them evenly to obtain the first solution.

[0056] Add 18.55g of anhydrous sodium carbonate to 300mL of deionized water and dissolve until homogeneous to obtain the second solution.

[0057] The two solutions were simultaneously added dropwise to a stirred reaction vessel, and a coprecipitation reaction was carried out at 70°C. The dropping rate of the first solution was 10 ml / min, and the dropping rate of the second solution was 15 ml / min. The pH of the coprecipitation reaction was adjusted to 7.3.

[0058] The coprecipitation reaction product was aged at 80℃ for 3 hours, filtered, and the filter cake was washed with deionized water 3 to 5 times. It was then dried in an oven at 110℃ for 12 hours to obtain the copper-based desulfurization adsorbent precursor.

[0059] Weigh 200g of copper-based desulfurization adsorbent precursor, 10g of guar gum powder, 50g of boehmite and 50g of kaolin and add them to a mixing device. Stir for 15 minutes to mix them evenly.

[0060] Weigh 85.5g of 30% silica sol, 6g of concentrated nitric acid and 120g of deionized water, and slowly add them to the mixing device in sequence. Mix for 15 minutes to obtain a uniform wet material.

[0061] The wet material was quickly transferred to an extruder with a 2mm round hole die and extruded into strips at a speed of 18r / min. After aging in air at room temperature for 6 hours, it was placed in an oven at 150℃ for 10 hours and then placed in a muffle furnace and calcined in air at a heating rate of 4℃ / min to 450℃ for 5 hours to prepare the shaped desulfurization adsorbent, denoted as PA3.

[0062] The desulfurization performance and mechanical strength of PA3 were tested according to the method in Example 1, and the results are as follows: Figure 1 and Figure 2 As shown in PA3, its sulfur penetration capacity is 19.06 mg / g and its mechanical strength is 58.56 N / cm.

[0063] Example 4

[0064] Weigh 12.08g of copper nitrate trihydrate, 14.88g of zinc nitrate hexahydrate, 6.38g of boehmite, 0.40g of nickel nitrate hexahydrate, and 0.47g of zirconium nitrate pentahydrate, add them to 200mL of deionized water, and dissolve them evenly to obtain the first solution.

[0065] Add 18.55g of anhydrous sodium carbonate to 300mL of deionized water and dissolve until homogeneous to obtain the second solution.

[0066] The two solutions were simultaneously added dropwise to a stirred reaction vessel, and a coprecipitation reaction was carried out at 70°C. The dropping rate of the first solution was 10 ml / min, and the dropping rate of the second solution was 15 ml / min. The pH of the coprecipitation reaction was adjusted to 7.5.

[0067] The coprecipitation reaction product was aged at 80℃ for 3 hours, filtered, and the filter cake was washed with deionized water 3 to 5 times. It was then dried in an oven at 110℃ for 12 hours to obtain the copper-based desulfurization adsorbent precursor.

[0068] Weigh 200g of copper-based desulfurization adsorbent precursor, 10g of guar gum powder, 40g of boehmite and 80g of kaolin and add them to a mixing device. Stir for 15 minutes to mix them evenly.

[0069] Weigh 85.5g of 30% silica sol, 6g of concentrated nitric acid and 120g of deionized water, and slowly add them to the mixing device in sequence. Mix for 15 minutes to obtain a uniform wet material.

[0070] The wet material was quickly transferred to an extruder with a 2mm round hole die and extruded into strips at a speed of 18r / min. After aging in air at room temperature for 6 hours, it was placed in an oven at 130℃ for 10 hours and then placed in a muffle furnace and calcined in air at a heating rate of 5℃ / min to 500℃ for 4 hours to prepare the shaped desulfurization adsorbent, denoted as PA4.

[0071] The desulfurization performance and mechanical strength of PA4 were tested according to the method in Example 1, and the results are as follows: Figure 1 and Figure 2 As shown in PA4, its sulfur penetration capacity is 17.89 mg / g and its mechanical strength is 60.45 N / cm.

[0072] Example 5

[0073] Weigh 200g of the copper-based desulfurization adsorbent precursor prepared in Example 1, 10g of guar gum powder, 26.7g of boehmite and 53.3g of kaolin and add them to a mixing device. Stir for 15 minutes to mix them evenly.

[0074] Weigh 85.5g of 30% silica sol, 6g of concentrated nitric acid and 120g of deionized water, and slowly add them to the mixing device in sequence. Mix for 15 minutes to obtain a uniform wet material.

[0075] The wet material was quickly transferred to an extruder with a 2mm round hole die and extruded into strips at a speed of 18r / min. After aging in air at room temperature for 6 hours, it was placed in an oven at 110℃ for 10 hours and then placed in a muffle furnace and calcined in air at a heating rate of 3℃ / min to 550℃ for 3 hours to prepare the shaped desulfurization adsorbent, denoted as PA5.

[0076] The desulfurization performance and mechanical strength of PA5 were tested according to the method in Example 1, and the results are as follows: Figure 1 and Figure 2 As shown in PA5, its sulfur penetration capacity is 18.14 mg / g and its mechanical strength is 55.51 N / cm.

[0077] Comparative Example 1

[0078] Weigh 7.25g of copper nitrate trihydrate, 8.93g of zinc nitrate hexahydrate, 3.74g of boehmite, 0.40g of nickel nitrate hexahydrate, and 0.32g of zirconium nitrate pentahydrate, add them to 200mL of deionized water, and dissolve them evenly to obtain the first solution.

[0079] Add 11.13g of anhydrous sodium carbonate to 350mL of deionized water and dissolve until homogeneous to obtain the second solution.

[0080] The two solutions were simultaneously added dropwise to a stirred reaction vessel, and a coprecipitation reaction was carried out at 70°C. The dropping rate of the first solution was 10 ml / min, and the dropping rate of the second solution was 15 ml / min. The pH of the coprecipitation reaction was adjusted to 7.5.

[0081] The coprecipitation reaction product was aged at 80℃ for 3 hours, filtered, and the filter cake was washed with deionized water 3 to 5 times. It was then dried in an oven at 110℃ for 12 hours to obtain the copper-based desulfurization adsorbent precursor.

[0082] The copper-based desulfurization adsorbent precursor was placed in a muffle furnace and heated to 350°C at a heating rate of 2°C / min, and calcined in air for 4.5 h to prepare desulfurization adsorbent powder.

[0083] Weigh 200g of desulfurization adsorbent powder, 10g of guar gum powder, 33.3g of boehmite and 66.7g of kaolin and add them to a mixing device. Stir for 15 minutes to mix them evenly.

[0084] Weigh 85.5g of 30% silica sol, 6g of concentrated nitric acid and 120g of deionized water, and slowly add them to the mixing device in sequence. Mix for 15 minutes to obtain a uniform wet material.

[0085] The wet material was quickly transferred to an extruder with a 2mm round hole die and extruded into strips at a speed of 18r / min. After aging in air at room temperature for 6 hours, it was placed in an oven and dried at 110℃ for 12 hours. Then, it was placed in a muffle furnace and calcined in air at a heating rate of 2℃ / min to 350℃ for 4.5 hours to prepare the shaped desulfurization adsorbent, denoted as PB1.

[0086] The desulfurization performance and mechanical strength of PB1 were tested according to the method in Example 1, and the results are as follows: Figure 1 and Figure 2 As shown in PB1, its sulfur penetration capacity is 18.69 mg / g, which is slightly lower than that of Example 1, but its mechanical strength is only 41.91 N / cm, which is significantly lower than that of Example 1, which is only 64.1 N / cm.

[0087] Comparative Example 2

[0088] Weigh 200g of the copper-based desulfurization adsorbent precursor prepared in Example 1, 10g of guar gum powder, 66.7g of boehmite and 33.3g of kaolin and add them to a mixing device. Stir for 15 minutes to mix them evenly.

[0089] Weigh 85.5g of 30% silica sol, 6g of concentrated nitric acid and 120g of deionized water, and slowly add them to the mixing device in sequence. Mix for 15 minutes to obtain a uniform wet material.

[0090] The wet material was quickly transferred to an extruder with a 2mm round hole die and extruded into strips at a speed of 18r / min. After aging in air at room temperature for 6 hours, it was placed in an oven at 120℃ for 12 hours and then placed in a muffle furnace and calcined in air at a heating rate of 3℃ / min to 400℃ for 6 hours to prepare the shaped desulfurization adsorbent, denoted as PB2.

[0091] The desulfurization performance and mechanical strength of PB2 were tested according to the method in Example 1, and the results are as follows: Figure 1 and Figure 2 As shown in PB2, its sulfur penetration capacity decreased to 15.35 mg / g, while its mechanical strength decreased to 36.67 N / cm.

[0092] Comparative Example 3

[0093] Weigh 200g of the copper-based desulfurization adsorbent precursor prepared in Example 1, 10g of guar gum powder, 75g of boehmite and 25g of kaolin and add them to a mixing device. Stir for 15 minutes to mix them evenly.

[0094] Weigh 85.5g of 30% silica sol, 6g of concentrated nitric acid and 120g of deionized water, and slowly add them to the mixing device in sequence. Mix for 15 minutes to obtain a uniform wet material.

[0095] The wet material was quickly transferred to an extruder with a 2mm round hole die and extruded into strips at a speed of 18r / min. After aging in air at room temperature for 6 hours, it was placed in an oven at 120℃ for 12 hours and then placed in a muffle furnace and calcined in air at a heating rate of 3℃ / min to 400℃ for 6 hours to prepare the shaped desulfurization adsorbent, denoted as PB3.

[0096] The desulfurization performance and mechanical strength of PB3 were tested according to the method in Example 1, and the results are as follows: Figure 1 and Figure 2 As shown in PB3, its sulfur penetration capacity decreased to 16.91 mg / g, while its mechanical strength also decreased significantly to 23.59 N / cm.

[0097] The desulfurization performance and mechanical strength test results of the molded desulfurization adsorbents prepared in Examples 1-5 and Comparative Examples 1-3 show that the present invention uses a copper-based desulfurization adsorbent precursor for molding. Due to the strong fluidity and packing state of the precursor material itself, or the strong interaction forces between powder particles, the molded desulfurization adsorbent has the greatest mechanical strength. Furthermore, the desulfurization adsorbent molded with the precursor will generate more micropores after calcination, resulting in a larger specific surface area, which can reduce the influence of internal diffusion during the desulfurization evaluation process and further improve the desulfurization activity of the molded desulfurization adsorbent. In contrast, the mechanical strength of Comparative Examples 1-3 decreased significantly, and the corresponding desulfurization performance also decreased accordingly.

[0098] The above embodiments of the present invention do not describe all details exhaustively, nor do they limit the present invention to the embodiments described above. Various changes, modifications, substitutions, and variations made by those skilled in the art to these embodiments without departing from the principles and spirit of the present invention should be included within the scope of protection of the present invention.

Claims

1. The application of a copper-based molded desulfurization adsorbent for ultra-deep thiophene removal in ultra-deep thiophene removal, wherein the molding method of the copper-based molded desulfurization adsorbent for ultra-deep thiophene removal is to use a copper-based desulfurization adsorbent precursor as raw material, mix it evenly with 30-60% by weight of a binder and 1-10% by weight of an extrusion aid, add silica sol nitric acid aqueous solution and knead to obtain a wet material, extrude it into shape using an extruder, age and dry it at room temperature, and calcine it at 350-550℃ for 3-8 hours to prepare the copper-based molded desulfurization adsorbent; in, The copper-based desulfurization adsorbent precursor is a precursor powder prepared according to the following method: 1) Weigh out 5-25 parts by weight of copper nitrate trihydrate, 6-30 parts by weight of zinc nitrate hexahydrate, 5-20 parts by weight of boehmite, 0.1-2 parts by weight of nickel nitrate hexahydrate, and 0.1-5 parts by weight of zirconium nitrate pentahydrate, and dissolve them evenly in deionized water to obtain the first solution; 2) Weigh 10-40 parts of anhydrous sodium carbonate and dissolve it evenly in deionized water to obtain a second solution; 3) Mix the first solution and the second solution at 40–90°C to carry out a co-precipitation reaction; 4) The coprecipitation reaction product is aged at 30-90℃ for 1-5 hours, washed and dried to obtain the copper-based desulfurization adsorbent precursor; The binder is a mixture of boehmite and kaolin in a mass ratio of 1:1 or 1:2, and the extrusion aid is guar gum powder.

2. The application according to claim 1, characterized in that: The concentration of the silica sol nitric acid aqueous solution is 20-50%, and the amount used is 30-60% of the mass of the copper-based desulfurization adsorbent precursor.

3. The application according to claim 1, characterized in that: The amount of nitric acid used in the silica sol nitric acid aqueous solution is 2 to 15% of the mass of the copper-based desulfurization adsorbent precursor.

4. The application according to claim 1, characterized in that: The kneading time is 10 to 30 minutes.

5. The application according to claim 1, characterized in that: The orifice diameter of the die used for extrusion molding is 1 to 4 mm.

6. The application according to claim 1, characterized in that: The extruder operates at a frequency of 10–30 r / min.

7. The application according to claim 1, characterized in that: The extruded wet material is aged in air at room temperature for no less than 4 hours before being dried.

8. The application according to claim 7, characterized in that: The extruded wet material is dried at 100-150℃ for 10-15 hours.

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