A cos hydrolysis catalyst with a three-dimensional felt-like skeleton structure and a preparation method and application thereof

Abstract

The application discloses a COS hydrolysis catalyst with a three-dimensional felt-like framework structure and a preparation method and application thereof, and belongs to the technical field of blast furnace gas desulfurization. The preparation method of the COS hydrolysis catalyst with the three-dimensional felt-like framework structure comprises the following steps: mixing an aluminum source, a surfactant and an organic salt in a solvent to obtain a mixture, performing a heating reaction, and performing calcination to complete the preparation. The surface of the hydrolysis catalyst contains a large number of defects, can increase the anchoring sites of metal components, improves the COS hydrolysis capacity of the catalyst, and improves the desulfurization efficiency. As the surfactant and soft template agent, hexadecyl trimethyl ammonium bromide can significantly optimize the specific surface area and mesoporous structure of the carrier by forming micelles to control the formation of aluminum species. Urea is slowly decomposed under hydrothermal conditions to release an alkali source, the pH of the system is gradually increased, and therefore, the aluminum-based carrier with uniform particle size, well-developed pore structure and uniformly distributed surface hydroxyl groups is obtained.

Description

Technical Field

[0001] This invention relates to the field of blast furnace gas desulfurization technology, and in particular to a COS hydrolysis catalyst with a three-dimensional felt-like skeleton structure, its preparation method, and its application. Background Technology

[0002] Blast furnace gas is a major byproduct gas produced during the blast furnace ironmaking process, and its most important use is as fuel. However, during combustion, the sulfides contained in the blast furnace gas are oxidized to form SO2, which not only causes air pollution but also leads to severe corrosion of downstream pipelines and equipment. Therefore, blast furnace gas must undergo effective desulfurization treatment before being transported and emitted.

[0003] The sulfur-containing species in blast furnace gas mainly include two categories: inorganic sulfur and organic sulfur. Among them, organic sulfur is mainly carbonyl sulfur (COS), with a volume fraction of approximately 200–300 mg / m³. 3 Inorganic sulfur is mainly in the form of hydrogen sulfide (H2S), with a volume fraction of approximately 50–100 mg / m³. 3 Current blast furnace gas desulfurization processes typically employ a "COS hydrolysis + H2S removal" technical route. This involves first converting COS to H2S through catalytic hydrolysis, then removing it along with the existing H2S. With the increasing demands for ultra-low emissions and comprehensive pollution and carbon reduction in the steel industry, implementing desulfurization at the blast furnace gas source can significantly reduce the load and operating costs of subsequent purification and environmental protection units. Therefore, efficient hydrolysis and deep removal of COS from blast furnace gas has become a key link in improving the clean utilization of blast furnace gas and achieving green development in the ironmaking process, placing higher demands on related processes and catalytic materials.

[0004] Currently, catalytic hydrolysis is the most promising engineering approach for the removal of carbonyl sulfide (COS) from blast furnace gas due to its simplicity and good compatibility with existing H2S removal processes. Domestic and international research has evolved from single-active-component formulations to synergistic designs involving "active-component-support-auxiliary agents." By controlling the pore structure, surface acidity / alkalinity, and water adsorption / activation capacity of the catalyst, efficient hydrolysis of COS under medium- and low-temperature conditions can be achieved, while also considering resistance to water vapor, sulfur poisoning, and long-term stability. Support systems have also expanded from traditional single oxides to diverse directions such as Al2O3, SiO2, TiO2, ZrO2, and Ce-based composite oxides, with systematic research focusing on the precise control of specific surface area, pore structure, and surface functional sites.

[0005] Among various supports, aluminum-based supports, represented by γ-Al₂O₃, dominate COS hydrolysis catalysts due to their high specific surface area, suitable mesoporous structure, tunable surface acidity / alkalinity, good thermal stability and mechanical strength, and mature large-scale preparation process. On the one hand, the surface of γ-Al₂O₃ can simultaneously provide the basic and Lewis acid sites required for COS hydrolysis, which is beneficial for the synergistic adsorption and activation of COS and H₂O. On the other hand, aluminum-based supports are easy to load with active components such as alkali metals, rare earth elements, and transition metals, forming stable, highly dispersed phases, ensuring both activity and selectivity while also considering low cost and engineering applicability. However, current COS hydrolysis catalysts still suffer from problems such as low catalytic activity, poor stability, susceptibility to poisoning, and generally complex preparation processes, requiring further improvement.

[0006] Therefore, developing a simple, low-cost, and stable long-lasting method for preparing hydrolysis catalysts has become an urgent technical problem to be solved. Summary of the Invention

[0007] The purpose of this invention is to provide a COS hydrolysis catalyst with a three-dimensional felt-like framework structure, its preparation method, and its application, to solve the aforementioned problems in the background art. The surface of the hydrolysis catalyst of this invention contains numerous defects, which can increase the anchoring sites for metal components, improve the catalyst's hydrolysis ability for COS, and enhance desulfurization efficiency. Hexadecyltrimethylammonium bromide, as a surfactant and soft template agent, can significantly optimize the specific surface area and mesoporous structure of the support by regulating the formation of aluminum species through micelles.

[0008] To achieve the above objectives, the present invention provides the following technical solution: One of the technical solutions of this invention is to provide a method for preparing a COS hydrolysis catalyst with a three-dimensional felt-like framework structure, comprising the following steps: An aluminum source, surfactant, and organic salt are mixed in a solvent to obtain a mixture, which is then heated and calcined to obtain the COS hydrolysis catalyst.

[0009] Preferably, the aluminum source includes aluminum nitrate.

[0010] Preferably, the organic carboxylate includes sodium citrate or sodium tartrate, and the amount added is 5-35% of the mass of the aluminum source; the organic amine salt includes urea, and the amount added is 5-35% of the mass of the aluminum source.

[0011] Preferably, the surfactant is hexadecyltrimethylammonium bromide, and the amount added is 10% of the mass of the aluminum source.

[0012] Preferably, after calcination, the process further includes an impregnation step of adding a dopant; the amount of the dopant added is 0-10% of the mass of the aluminum source and is not 0; the dopant includes a potassium source and a neodymium source.

[0013] Preferably, the mass ratio of the potassium source to the neodymium source is (1-5):(1-5); the potassium source includes potassium carbonate, potassium nitrate, or potassium hydroxide; and the neodymium source includes neodymium nitrate or neodymium chloride.

[0014] Preferably, the heating reaction is carried out at a temperature of 100℃-180℃ for 12h-24h.

[0015] Preferably, the roasting temperature is 500°C and the time is 4 hours.

[0016] The second technical solution of the present invention provides a COS hydrolysis catalyst with a three-dimensional felt-like framework structure obtained according to the above preparation method.

[0017] The third technical solution of the present invention provides an application of the above-mentioned COS hydrolysis catalyst with a three-dimensional felt-like skeleton structure in the field of organic sulfur removal from blast furnace gas.

[0018] The fourth technical solution of the present invention provides a method for removing organic sulfur from blast furnace gas, characterized in that the above-mentioned COS hydrolysis catalyst with a three-dimensional felt-like skeleton structure is used as the catalytic component for organic sulfur removal treatment.

[0019] The beneficial technical effects of the present invention are as follows: The hydrolysis catalyst prepared by this invention has many surface defects and pore structures, which is beneficial to the dispersion, binding and stable loading of active metal components (K, Nd) on the support surface, thereby improving the catalyst's hydrolysis ability for COS and desulfurization efficiency.

[0020] Hexadecyltrimethylammonium bromide, acting as a surfactant and soft template agent, can regulate the nucleation, growth, and pore structure formation of aluminum species. Urea slowly decomposes under hydrothermal conditions to release ammonia, causing the system pH to rise gradually and preventing the aluminum source from rapidly precipitating. Sodium citrate or sodium tartrate, as organic carboxylate salts, can complex with aluminum ions, regulating the hydrolysis, nucleation, and precipitation rates of aluminum species, and acting as a buffer to regulate pH changes. Through the synergistic effect of these components, an aluminum-based support with relatively uniform particle size, well-developed pore structure, and uniform surface hydroxyl distribution can be obtained.

[0021] An aluminum-based framework with high specific surface area and well-developed mesoporous structure was constructed using a hydrothermal-calcination process. Alkali metal potassium and rare earth metal neodymium were then introduced onto its surface using an impregnation method, achieving high dispersion and synergistic regulation of K and Nd on the support surface. By rationally designing the K / Nd loading ratio, the catalyst of this invention forms a suitable combination of basic and Lewis acid sites on the γ-Al₂O₃ surface. This not only facilitates the synergistic adsorption and activation of organic sulfur and water molecules but also improves the catalyst's thermal stability and resistance to deactivation under aqueous and sulfur-containing atmospheres, thereby significantly enhancing the hydrolysis activity and lifespan of organic sulfur species such as COS under medium- and low-temperature conditions.

[0022] The preparation method provided by this invention is simple, low-cost, and has high desulfurization accuracy, making it highly valuable for application. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 (a), (b), (c), and (d) are SEM images of the COS hydrolysis catalyst of Example 1 of the present invention at different magnifications. Detailed Implementation

[0025] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the present invention.

[0026] Furthermore, regarding the numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, are also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0027] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. It should be noted that any aspects of this invention not described in detail are conventional practices in the art and are not the focus of this invention.

[0028] The terms “comprising,” “including,” “having,” “containing,” etc., used in this invention are all open-ended terms, meaning that they include but are not limited to.

[0029] This invention discloses a method for preparing a COS hydrolysis catalyst with a three-dimensional felt-like framework structure, comprising the following steps: An aluminum source, surfactant, and organic salt are mixed in a solvent to obtain a mixture, which is then heated and calcined to obtain the COS hydrolysis catalyst.

[0030] Preferably, the aluminum source includes aluminum nitrate.

[0031] Preferably, the organic carboxylate includes sodium citrate or sodium tartrate; the organic amine salt includes urea, and the amount added is 5-35% of the mass of the aluminum source.

[0032] Preferably, the amount of organic carboxylate added is 5-35% of the mass of aluminum source, for example, it can be 5%, 8%, 10%, 15%, 17.5%, 20%, 25%, 30% or 35%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0033] Within the limits of the organic hydroxy acid salts specified in this invention, it is helpful to simultaneously exert their structure-guiding and surface-modifying effects, forming a hydrotalcite phase desulfurization adsorbent with excellent morphology and performance, and significantly improving the desulfurization capacity.

[0034] Preferably, the surfactant is hexadecyltrimethylammonium bromide, and the amount added is 10% of the mass of the aluminum source.

[0035] Preferably, after calcination, the process further includes a step of adding a dopant for impregnation; the dopant includes a potassium source and a neodymium source.

[0036] Preferably, the mass ratio of the potassium source to the neodymium source is (1-5):(1-5).

[0037] Preferably, the potassium source includes potassium carbonate, potassium nitrate, or potassium hydroxide.

[0038] Preferably, the neodymium source includes neodymium nitrate or neodymium chloride.

[0039] Preferably, the amount of dopant added is 0-10% of the mass of the aluminum source and is not 0. For example, it can be 1%, 3%, 5%, 7%, 9% or 10%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0040] Preferably, the solvent is water.

[0041] Preferably, the mixing is carried out under stirring conditions, and the stirring speed is 100r / min-150r / min, for example, it can be 100r / min, 110r / min, 120r / min, 130r / min, 140r / min or 150r / min, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0042] Preferably, the mixing temperature is 20℃-30℃, for example, it can be 20℃, 22℃, 24℃, 26℃, 28℃ or 30℃, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0043] Preferably, the mixing time is 30-60 minutes, for example, 30 minutes, 35 minutes, 40 minutes, 50 minutes, 55 minutes or 60 minutes, but not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0044] Preferably, the temperature of the heating reaction is 100℃-180℃, for example, it can be 100℃, 120℃, 140℃, 160℃ or 180℃, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0045] Preferably, the heating reaction time is 12h-24h, for example, it can be 12h, 16h, 20h, 22h or 24h, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0046] Preferably, after the heating reaction, the process further includes washing and drying steps.

[0047] Preferably, the washing is performed until the pH value of the washing solution is 7-8, for example, it can be 7, 7.2, 7.4, 7.6, 7.8 or 8, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0048] Preferably, the detergent used for washing includes deionized water and / or ethanol.

[0049] Preferably, the washing temperature is 20℃-30℃, for example, it can be 20℃, 22℃, 24℃, 26℃, 28℃ or 30℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0050] Preferably, the washing method includes centrifugal washing; the washing speed of the centrifugal washing is 4000 r / min-5000 r / min, for example, it can be 4000 r / min, 4200 r / min, 4400 r / min, 4600 r / min, 4800 r / min or 5000 r / min, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0051] Preferably, the drying temperature is 80℃-120℃, for example, it can be 80℃, 90℃, 100℃, 110℃ or 120℃, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0052] Preferably, the drying time is 6h-10h, for example, it can be 6h, 7h, 8h, 9h or 10h, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0053] Preferably, the roasting temperature is 500°C and the time is 4 hours.

[0054] More preferably, the preparation method includes the following steps: (1) Dissolve aluminum source, surfactant and organic salt in deionized water and mechanically stir at 20℃-30℃ to obtain a clear and transparent mixture; the mechanical stirring speed is 100r / min-150r / min and the mechanical stirring time is 30min-60min; (2) The mixture is transferred to a hydrothermal synthesis reactor lined with polytetrafluoroethylene and heated at 100℃-180℃ for 12h-24h to obtain the precursor; (3) The precursor is centrifuged, washed and dried sequentially, and then calcined at 500°C for 4 hours to obtain the COS hydrolysis catalyst; the centrifugation is performed until the pH of the washing liquid is 7-8, the washing agent includes deionized water and / or ethanol, the temperature of the centrifugation is 20°C-30°C, and the centrifugation speed is 4000 r / min-5000 r / min; the drying temperature is 80°C-120°C, and the time is 6 hours-10 hours.

[0055] The present invention also discloses a COS hydrolysis catalyst with a three-dimensional felt-like framework structure obtained according to the above preparation method.

[0056] The present invention also discloses the application of the above-mentioned COS hydrolysis catalyst with a three-dimensional felt-like framework structure in the field of organic sulfur removal from blast furnace gas.

[0057] The present invention also discloses a method for removing organic sulfur from blast furnace gas, using the above-mentioned COS hydrolysis catalyst with a three-dimensional felt-like skeleton structure as the catalytic component for organic sulfur removal treatment.

[0058] Preferably, the temperature for the organic sulfur removal treatment is 30℃-120℃, for example, it can be 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, 110℃ or 120℃, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0059] Preferably, the blast furnace gas feed space velocity for the organic sulfur removal treatment is 80,000 h⁻¹. -1 -150000h -1 For example, it could be 80000h -1 90000h -1 100000h -1 110000h -1 120000h -1 130000h -1 140000h -1 Or 150,000h -1 However, this does not limit the listed values; other unlisted values ​​within the range are also applicable.

[0060] Preferably, the concentration of carbonyl sulfide (COS) in the organic sulfur removal treatment is 150ppm-200ppm, for example, it can be 150ppm, 160ppm, 170ppm, 180ppm, 190ppm or 200ppm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0061] Preferably, the amount of COS hydrolysis catalyst used in the organic sulfur removal treatment is 100mg-200mg, for example, it can be 100mg, 120mg, 140mg, 160mg, 180mg or 200mg, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0062] Preferably, the oxygen concentration of the organic sulfur removal treatment is 0.3 vol%-0.5 vol%, for example, it can be 0.3 vol%, 0.35 vol%, 0.4 vol%, 0.45 vol% or 0.5 vol%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0063] Preferably, the water vapor concentration of the organic sulfur removal treatment is 1 vol%-5 vol%, for example, it can be 1 vol%, 2 vol%, 3 vol%, 4 vol%, 5 vol%, but it is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0064] Preferably, the equilibrium gas for the organic sulfur removal treatment includes nitrogen.

[0065] More preferably, the organic sulfur removal treatment includes the following steps: The COS hydrolysis catalyst is added to a fixed reaction bed, and then blast furnace gas is introduced for organic sulfur removal treatment; the reaction temperature for organic sulfur removal treatment is 30℃-120℃, and the blast furnace gas feed space velocity is 80000 h⁻¹. -1 -150000h -1 The carbonyl sulfur concentration is 150ppm-200ppm, the oxygen concentration is 0.3vol%-0.5vol%, the water vapor concentration is 3vol%-5vol%, and the balance gas includes nitrogen.

[0066] The relevant concentrations refer to the actual concentrations of each component in the gas phase of blast furnace gas after two-stage dust removal and before entering the desulfurization tower, rather than the concentrations in the fixed-bed reaction bed.

[0067] Using the COS hydrolysis catalyst of the present invention, organic sulfur carbonyl sulfide (COS) in blast furnace gas can be hydrolyzed to generate inorganic sulfur hydrogen sulfide (H2S) and CO2.

[0068] All raw materials used in the following embodiments and comparative examples of the present invention are commercially available products.

[0069] Example 1 A method for preparing a COS hydrolysis catalyst with a three-dimensional felt-like framework structure, comprising the following steps: (1) Aluminum nitrate nonahydrate, hexadecyltrimethylammonium bromide, and an organic carboxylate salt were dissolved in deionized water and mechanically stirred at 25°C to obtain a clear and transparent mixture; the mechanical stirring speed was 100 r / min, and the mechanical stirring time was 45 min. The total mass of aluminum nitrate nonahydrate was 5 g; the organic amine salt was urea, and the amount added was 0.5 g (10% of the mass of the aluminum source); the amount added was hexadecyltrimethylammonium bromide, which was 0.5 g (10% of the mass of the aluminum source).

[0070] (2) The above mixture was transferred to a hydrothermal synthesis reactor lined with polytetrafluoroethylene and hydrothermally reacted at 100°C for 12 h to obtain the precursor.

[0071] (3) The precursor was centrifuged and washed and dried in sequence; the centrifugation was carried out until the pH of the washing liquid was 8, the washing agent was deionized water, the centrifugation temperature was 25℃ and the rotation speed was 4500r / min; the drying temperature was 80℃ and the time was 6h.

[0072] (4) The dried sample was calcined to obtain COS hydrolysis catalyst; the calcination instrument was a muffle furnace, the calcination temperature was 500℃, and the time was 4h.

[0073] Figure 1 Images (a), (b), (c), and (d) are SEM images of the COS hydrolysis catalyst of Example 1 of this invention at different magnifications. As can be seen from the images, the COS hydrolysis catalyst prepared in this example has uniform particle size and is composed of stacked strip-shaped nanosheets.

[0074] Example 2 A method for preparing a COS hydrolysis catalyst with a three-dimensional felt-like framework structure, comprising the following steps: (1) Aluminum nitrate nonahydrate, hexadecyltrimethylammonium bromide, and an organic carboxylate were dissolved in deionized water and mechanically stirred at 20°C to obtain a clear and transparent mixture; the mechanical stirring speed was 120 r / min, and the mechanical stirring time was 60 min. The total mass of aluminum nitrate nonahydrate was 7 g; the organic carboxylate was sodium citrate, and the amount added was 0.7 g (10% of the mass of the aluminum source); the amount added was hexadecyltrimethylammonium bromide, and the amount added was 0.7 g (10% of the mass of the aluminum source).

[0075] (2) The above mixture was transferred to a hydrothermal synthesis reactor lined with polytetrafluoroethylene and hydrothermally reacted at 120°C for 24 hours to obtain the precursor.

[0076] (3) The precursor was centrifuged and washed and dried in sequence; the centrifugation was carried out until the pH of the washing liquid was 8, the washing agent was ethanol, the centrifugation temperature was 20℃ and the rotation speed was 5000r / min; the drying temperature was 120℃ and the time was 6h.

[0077] (4) The dried sample was calcined to obtain COS hydrolysis catalyst; the calcination instrument was a muffle furnace, the calcination temperature was 500℃, and the time was 4h.

[0078] Example 3 A method for preparing a COS hydrolysis catalyst with a three-dimensional felt-like framework structure, comprising the following steps: (1) Aluminum nitrate nonahydrate, hexadecyltrimethylammonium bromide, and an organic carboxylate were dissolved in deionized water and mechanically stirred at 30°C to obtain a clear and transparent mixture; the mechanical stirring speed was 150 r / min, and the mechanical stirring time was 60 min. The total mass of aluminum nitrate nonahydrate was 5 g; the organic carboxylate was sodium tartrate, and the amount added was 0.5 g (10% of the mass of the aluminum source); the amount added was hexadecyltrimethylammonium bromide, and the amount added was 0.5 g (10% of the mass of the aluminum source).

[0079] (2) The above mixture was transferred to a hydrothermal synthesis reactor lined with polytetrafluoroethylene and hydrothermally reacted at 180°C for 12 h to obtain the precursor.

[0080] (3) The precursors were centrifuged and washed and dried in sequence; the centrifugation was carried out until the pH of the washing solution was 7.5, the washing agent was deionized water, the centrifugation temperature was 30℃ and the rotation speed was 4000r / min; the drying temperature was 80℃ and the time was 10h.

[0081] (4) The dried sample was calcined to obtain COS hydrolysis catalyst; the calcination instrument was a muffle furnace, the calcination temperature was 500℃, and the time was 4h.

[0082] Example 4 A method for preparing a COS hydrolysis catalyst with a three-dimensional felt-like framework structure, comprising the following steps: (1) Aluminum nitrate nonahydrate, hexadecyltrimethylammonium bromide, and an organic carboxylate salt were dissolved in deionized water and mechanically stirred at 25°C to obtain a clear and transparent mixture; the mechanical stirring speed was 100 r / min, and the mechanical stirring time was 45 min. The total mass of aluminum nitrate nonahydrate was 5 g; the organic amine salt was urea, added at 0.5 g (10% of the aluminum source mass); the amount of hexadecyltrimethylammonium bromide added was 0.5 g (10% of the aluminum source mass). (2) The above mixture was transferred to a hydrothermal synthesis reactor lined with polytetrafluoroethylene and hydrothermally reacted at 100°C for 12 h to obtain the precursor.

[0083] (3) The precursors were centrifuged and washed and dried in sequence; the centrifugation was carried out until the pH of the washing liquid was 8, the washing agent was deionized water, the centrifugation temperature was 25℃ and the rotation speed was 4500r / min; the drying temperature was 80℃ and the time was 6h.

[0084] (4) The dried sample was calcined; the calcination instrument was a muffle furnace, the calcination temperature was 500℃, and the time was 4h. Then the calcined product was added to 200mL of deionized water and mixed. A loaded metal precursor salt was added as a dopant to obtain the COS hydrolysis catalyst; the dopant was composed of potassium nitrate and neodymium nitrate in a mass ratio of 1:1, and the total amount added was 0.25g (5% of the mass of aluminum source).

[0085] Example 5 The only difference between this embodiment and Embodiment 4 is that the dopant is modified to consist of potassium nitrate and neodymium nitrate in a mass ratio of 1:5.

[0086] Example 6 The only difference between this embodiment and Embodiment 4 is that the dopant is modified to consist of potassium nitrate and neodymium nitrate in a mass ratio of 5:1.

[0087] Example 7 The only difference between this embodiment and Example 1 is that the total mass of aluminum nitrate nonahydrate in step (1) is changed from 5g to 1g. The amounts of organic carboxylate and hexadecyltrimethylammonium bromide added are also adjusted accordingly, strictly maintaining a mass of 10% of the aluminum source.

[0088] Example 8 The only difference between this embodiment and Example 1 is that the total mass of aluminum nitrate nonahydrate in step (1) is changed from 5g to 2g. The amounts of organic carboxylate and hexadecyltrimethylammonium bromide added are also adjusted accordingly, strictly maintaining a mass of 10% of the aluminum source.

[0089] Example 9 The only difference between this embodiment and Example 1 is that the total mass of aluminum nitrate nonahydrate in step (1) is changed from 5g to 4g. The amounts of organic carboxylate and hexadecyltrimethylammonium bromide added are also adjusted accordingly, strictly maintaining a mass of 10% of the aluminum source.

[0090] Example 10 The only difference between this embodiment and Example 1 is that the total mass of aluminum nitrate nonahydrate in step (1) is changed from 5g to 6g. The amounts of organic carboxylate and hexadecyltrimethylammonium bromide added are also adjusted accordingly, strictly maintaining 10% of the aluminum source mass.

[0091] Example 11 The only difference between this embodiment and Example 1 is that the total mass of aluminum nitrate nonahydrate in step (1) is changed from 5g to 8g. The amounts of organic carboxylate and hexadecyltrimethylammonium bromide added are also adjusted accordingly, strictly maintaining a mass of 10% of the aluminum source.

[0092] Example 12 The only difference between this embodiment and Example 1 is that the total mass of aluminum nitrate nonahydrate in step (1) is changed from 5g to 9g. The amounts of organic carboxylate and hexadecyltrimethylammonium bromide added are also adjusted accordingly, strictly maintaining a mass of 10% of the aluminum source.

[0093] Example 13 The only difference between this embodiment and Example 1 is that the total mass of aluminum nitrate nonahydrate in step (1) is changed from 5g to 10g. The amounts of organic carboxylate and hexadecyltrimethylammonium bromide added are also adjusted accordingly, strictly maintaining a mass of 10% of the aluminum source.

[0094] Example 14 The only difference between this embodiment and Embodiment 1 is that the amount of urea added is changed from 10% of the mass of the aluminum source to 5% of the mass of the aluminum source.

[0095] Example 15 The only difference between this embodiment and Embodiment 1 is that the amount of urea added is changed from 10% of the mass of the aluminum source to 20% of the mass of the aluminum source.

[0096] Example 16 The only difference between this embodiment and embodiment 4 is that the potassium nitrate in step (4) is replaced with an equal mass of potassium carbonate.

[0097] Example 17 The only difference between this embodiment and embodiment 4 is that the potassium nitrate in step (4) is replaced with an equal mass of potassium hydroxide.

[0098] Example 18 The only difference between this embodiment and embodiment 4 is that the neodymium nitrate in step (4) is replaced with an equal mass of neodymium chloride.

[0099] Example 19 The only difference between this embodiment and embodiment 4 is that the total amount of dopant added in step (4) is changed from 5% of the aluminum source mass to 10% of the aluminum source mass.

[0100] Example 20 The only difference between this embodiment and embodiment 1 is that, except that the temperature of the hydrothermal reaction in step (2) is changed from 100°C to 120°C, everything else is the same as in embodiment 1.

[0101] Example 21 The only difference between this embodiment and embodiment 1 is that, except that the temperature of the hydrothermal reaction in step (2) is changed from 100°C to 150°C, everything else is the same as in embodiment 1.

[0102] Example 22 The only difference between this embodiment and embodiment 1 is that the hydrothermal reaction time in step (2) is changed from 12h to 18h, while the rest is the same as in embodiment 1.

[0103] Example 23 The only difference between this embodiment and embodiment 1 is that the hydrothermal reaction time in step (2) is changed from 12h to 24h, while the rest is the same as in embodiment 1.

[0104] Comparative Example 1 The only difference between this comparative example and Example 1 is that aluminum nitrate nonahydrate in step (1) is omitted.

[0105] Comparative Example 2 The only difference between this comparative example and Example 1 is that the aluminum source in step (1) is replaced with aluminum sulfate instead of aluminum nitrate nonahydrate.

[0106] Comparative Example 3 The only difference between this comparative example and Example 1 is that urea is not added in step (1).

[0107] Comparative Example 4 The only difference between this comparative example and Example 1 is that the urea in step (1) is replaced with equal masses of ethylenediamine and methanol (mass ratio of 1:1).

[0108] Comparative Example 5 The only difference between this comparative example and Example 1 is that hexadecyltrimethylammonium bromide is not added in step (1).

[0109] Application Example 1-1 A method for removing organic sulfur from blast furnace gas, comprising the following steps: 100 mg (15% of the total catalyst mass in the bed) of the COS hydrolysis catalyst from Example 1 was added to a fixed reaction bed, and then blast furnace gas was introduced for organic sulfur removal treatment. The treated gas was obtained after treatment. The reaction temperature for organic sulfur removal treatment was 120 °C, and the feed space velocity was 100,000 h⁻¹. -1 The carbonyl sulfur concentration was 150 ppm, the oxygen concentration was 0.3 vol%, and the water vapor concentration was 3 vol%. A balance gas (nitrogen) was also passed through the system.

[0110] Application Example 1-2 A method for removing organic sulfur from blast furnace gas, comprising the following steps: 100 mg (15% of the total catalyst mass in the bed) of the COS hydrolysis catalyst from Example 2 was added to a fixed reaction bed, and then blast furnace gas was introduced for organic sulfur removal treatment. The treated gas was obtained after treatment. The reaction temperature for organic sulfur removal treatment was 120°C, and the feed space velocity was 100,000 h⁻¹. -1The carbonyl sulfur concentration was 150 ppm, the oxygen concentration was 0.3 vol%, and the water vapor concentration was 3 vol%. A balance gas (nitrogen) was also passed through the system.

[0111] Application Examples 1-3 A method for removing organic sulfur from blast furnace gas, comprising the following steps: 100 mg (15% of the total catalyst mass in the bed) of the COS hydrolysis catalyst from Example 3 was added to a fixed reaction bed, and then blast furnace gas was introduced for organic sulfur removal treatment. The treated gas was obtained after treatment. The reaction temperature for organic sulfur removal treatment was 120°C, and the feed space velocity was 100,000 h⁻¹. -1 The carbonyl sulfur concentration was 150 ppm, the oxygen concentration was 0.3 vol%, and the water vapor concentration was 3 vol%. A balance gas (nitrogen) was also passed through the system.

[0112] Application Example 2 A method for removing organic sulfur from blast furnace gas, comprising the following steps: 100 mg (15% of the total catalyst mass in the bed) of the COS hydrolysis catalyst from Example 1 was added to a fixed reaction bed, and then blast furnace gas was introduced for organic sulfur removal treatment. The treated gas was obtained after treatment. The reaction temperature for organic sulfur removal treatment was 30°C, and the feed space velocity was 120,000 h⁻¹. -1 The carbonyl sulfur concentration was 180 ppm, the oxygen concentration was 0.4 vol%, and the water vapor concentration was 4 vol%. A balance gas (nitrogen) was also passed through the system.

[0113] Application Example 3 A method for removing organic sulfur from blast furnace gas, comprising the following steps: 100 mg (15% of the total catalyst mass in the bed) of the COS hydrolysis catalyst from Example 1 was added to a fixed reaction bed, and then blast furnace gas was introduced for organic sulfur removal treatment. The treated gas was obtained after treatment. The reaction temperature for organic sulfur removal treatment was 30°C, and the feed space velocity was 150,000 h⁻¹. -1 The carbonyl sulfur concentration was 200 ppm, the oxygen concentration was 0.5 vol%, the water vapor concentration was 5 vol%, and a balance gas (nitrogen) was also passed through during the process.

[0114] Application Example 4 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in example 4 is used.

[0115] Application Example 5 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in example 5 is used.

[0116] Application Example 6 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 6 is used.

[0117] Application Example 7 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 7 is used.

[0118] Application Example 8 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 8 is used.

[0119] Application Example 9 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 9 is used.

[0120] Application Example 10 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 10 is used.

[0121] Application Example 11 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 11 is used.

[0122] Application Example 12 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 12 is used.

[0123] Application Example 13 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 13 is used.

[0124] Application Example 14 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 14 is used.

[0125] Application Example 15 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 15 is used.

[0126] Application Example 16 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 16 is used.

[0127] Application Example 17 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 17 is used.

[0128] Application Example 18 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 18 is used.

[0129] Application Example 19 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 19 is used.

[0130] Application Example 20 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 20 is used.

[0131] Application Example 21 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in example 21 is used.

[0132] Application Example 22 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in example 22 is used.

[0133] Application Example 23 The only difference between this application example and application example 1-1 is that the COS hydrolysis catalyst prepared in Example 23 is used.

[0134] Comparative Application Example 1 The only difference between this comparative application example and application example 1-1 is that the COS hydrolysis catalyst prepared in comparative example 1 is used.

[0135] Comparative Application Example 2 The only difference between this comparative application example and application example 1-1 is that the COS hydrolysis catalyst prepared in comparative example 2 is used.

[0136] Comparative Application Example 3 The only difference between this comparative application example and application example 1-1 is that the COS hydrolysis catalyst prepared in comparative example 3 is used.

[0137] Comparative Application Example 4 The only difference between this comparative application example and application example 1-1 is that the COS hydrolysis catalyst prepared in comparative example 4 is used.

[0138] Comparative Application Example 5 The only difference between this comparative application example and application example 1-1 is that the COS hydrolysis catalyst prepared in comparative example 5 is used.

[0139] Test methods The processed gases obtained from the above application examples and comparative application examples were analyzed for product composition using a GC-2018 gas chromatograph. The detection system was equipped with a flame ionization detector (FID) and a methane conversion furnace. The chromatographic analysis conditions were as follows: column oven temperature 60 ℃, vaporization chamber temperature 200 ℃, flame ionization temperature 160 ℃, and methane conversion furnace temperature 360 ​​℃. The hydrolysis conversion efficiency of carbonyl sulfide (COS) was calculated based on the chromatographic peak area and the external standard method, and the results are shown in Table 1.

[0140] Table 1 The test results show that: (1) Application Example 6 (prepared using Example 6, K:Nd=5:1) at 120℃ for 100,000 h -1 At high space velocities, a COS hydrolysis conversion efficiency of 100% was achieved. Compared with undoped application example 1-1 (65.3%) and doped application example 4 (K:Nd=1:1, 76.5%), the efficiency of application example 6 (5:1) was significantly improved; however, when the Nd content was too high (application example 5, K:Nd=1:5, 63.3%), the efficiency decreased slightly, indicating that the K to Nd ratio within a suitable range is the key to enabling efficient COS hydrolysis technology.

[0141] (2) The catalyst prepared in Example 1 has a three-dimensional felt-like framework composed of stacked strip-shaped nanosheets. This structure provides a huge specific surface area and abundant active sites, making it suitable even at 100,000 h⁻¹. -1 At extremely high space velocities, Application Example 1-1 still maintained a conversion rate of 65.3%. In contrast, Comparative Example 1 (no aluminum source, 0%), Comparative Example 3 (no urea, 13.2%), and Comparative Example 4 (replaced organic base, 5.6%) showed extremely low conversion rates, indicating that the aluminum-based framework and the three-dimensional morphology formed with urea assistance are crucial to catalytic performance.

[0142] (3) Regarding the metal source: Application Example 6 (potassium nitrate) showed the best results, followed by Application Example 17 (potassium hydroxide, 51.5%), while Application Example 16 (potassium carbonate, 32.3%) performed poorly. This may be because nitrate ions are easily and completely decomposed during calcination, promoting efficient dispersion of potassium. Potassium carbonate has a high decomposition temperature and is prone to leaving residues that cover active sites. Strongly alkaline potassium hydroxide may cause localized corrosion to the aluminum-based framework during impregnation. Neodymium nitrate (Application Example 4) performed excellently, while neodymium chloride (Application Example 18, 1%) almost deactivated the catalyst. This may be due to active site coverage caused by chloride ion poisoning.

[0143] (4) The catalyst exhibited excellent activity at 120°C for organic sulfur removal (e.g., 89.8% in Application Example 21), but the conversion rate was only 4%-5% at near-room temperature (Application Examples 2 and 3). Increasing the hydrothermal synthesis temperature (from 95°C to 185°C, Application Examples 20 vs 21) significantly improved the conversion efficiency (from 65.3% to 89.8%), because higher synthesis temperatures are conducive to the formation of more stable active crystalline phases or more regular framework structures.

[0144] Replacing the aluminum source with aluminum sulfate from aluminum nitrate significantly reduces the COS hydrolysis conversion efficiency, mainly due to residual sulfate ions on the carrier surface. Aluminum sulfate has a high decomposition temperature, and the residual sulfate ions make the alumina surface highly acidic, weakening its adsorption capacity with acidic COS gas, thus leading to a significant decrease in hydrolysis efficiency.

[0145] In summary, the COS hydrolysis catalyst with a three-dimensional felt-like framework structure prepared in this invention successfully achieved complete COS conversion under high space velocity conditions by adjusting the types and proportions of dopants and combining them with a unique three-dimensional nanosheet stacked structure. This catalyst not only overcomes the shortcomings of traditional aluminum-based catalysts, such as low activity and susceptibility to poisoning, but also opens up a reaction pathway with a lower energy barrier through the synergistic effect of K and Nd, demonstrating excellent industrial application value.

[0146] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for preparing a COS hydrolysis catalyst with a three-dimensional felt-like framework structure, characterized in that, Includes the following steps: An aluminum source, surfactant, and organic salt are mixed in a solvent to obtain a mixture, which is then heated and calcined to obtain the COS hydrolysis catalyst. The organic salt is an organic carboxylic acid salt or an organic amine salt.

2. The preparation method according to claim 1, characterized in that, The aluminum source includes aluminum nitrate.

3. The preparation method according to claim 1, characterized in that, The organic carboxylic acid salt includes sodium citrate or sodium tartrate, and the amount added is 5-35% of the mass of the aluminum source; the organic amine salt includes urea, and the amount added is 5-35% of the mass of the aluminum source.

4. The preparation method according to claim 1, characterized in that, The surfactant is hexadecyltrimethylammonium bromide, and the amount added is 10% of the mass of the aluminum source.

5. The preparation method according to claim 1, characterized in that, After the calcination, the process further includes an impregnation step by adding a dopant; the amount of the dopant added is 0-10% of the mass of the aluminum source and is not zero; the dopant includes a potassium source and a neodymium source; The mass ratio of the potassium source to the neodymium source is (1-5):(1-5); the potassium source includes potassium carbonate, potassium nitrate, or potassium hydroxide; the neodymium source includes neodymium nitrate or neodymium chloride.

6. The preparation method according to claim 1, characterized in that, The heating reaction is carried out at a temperature of 100℃-180℃ for 12h-24h.

7. The preparation method according to claim 1, characterized in that, The roasting temperature is 500℃ and the time is 4 hours.

8. A COS hydrolysis catalyst with a three-dimensional felt-like framework structure obtained by the preparation method according to any one of claims 1-7.

9. The application of the COS hydrolysis catalyst with a three-dimensional felt-like framework structure as described in claim 8 in the field of organic sulfur removal from blast furnace gas.

10. A method for removing organic sulfur from blast furnace gas, characterized in that, The COS hydrolysis catalyst with a three-dimensional felt-like framework structure as described in claim 8 is used as the catalytic component for the removal of organic sulfur.

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