Catalyst for catalytic combustion and deoxidation, method for preparing the same, and method for catalytic combustion of hydrogen and method for oxygen removal

Abstract

The application discloses a catalyst for catalytic combustion and deoxidization, a preparation method of the catalyst, a hydrogen catalytic combustion method and an oxygen removal method of oxygen-containing hydrogen, and the catalyst comprises a silicon molecular sieve, tungsten and a noble metal, and the contact angle of the catalyst is 90-130 degrees. The silicon molecular sieve is modified by in-situ doping of tungsten, the hydrophobic property of the carrier is improved, the residence time of water on the surface of the catalyst is reduced, the catalytic efficiency of the catalyst at low temperature or even zero is improved, the starting temperature is reduced, and the service life of the catalyst is prolonged. In addition, the noble metal is not prone to sintering during the catalytic process due to the confinement effect of the molecular sieve.

Description

Technical Field

[0001] This invention relates to catalysts for catalytic combustion and catalytic deoxygenation of hydrogen and their preparation methods, as well as methods for catalytic combustion of hydrogen and methods for removing oxygen from oxygen-containing hydrogen. Background Technology

[0002] The reaction between hydrogen and oxygen is a highly exothermic reaction; the combustion process is uncontrollable, temperatures can exceed 1000℃, and it may lead to some side reactions. For example, oxygen and nitrogen react at high temperatures to produce NO. x In contrast, catalytic combustion refers to the catalytic reaction of oxygen and hydrogen to produce water under the action of a noble metal deoxidizer (such as Pt or Pd). The hydrogen catalytic combustion process occurs on the catalyst surface as a flameless oxidation process, requiring no ignition and exhibiting no flame flashback, effectively avoiding NO₂. x The combustion process is safer and more controllable because it eliminates the generation of harmful gases. Hydrogen catalytic combustion can be used for the purification of leaked hydrogen, hydrogen sensors, and hydrogen-powered heating devices. Furthermore, hydrogen catalytic combustion has important applications in hydrogen catalytic deoxygenation. Currently, industrial hydrogen production mainly comes from fossil fuels and water electrolysis. During hydrogen production, some oxygen inevitably mixes in, affecting the purity of the hydrogen. The concentration and purity of oxygen in hydrogen have a significant impact on its use; for example, the presence of oxygen reduces catalyst activity and affects the output performance and stability of fuel cells. Catalytic deoxygenation is a widely used deoxygenation method in industry, with advantages such as high catalytic efficiency and a wide operating temperature range. It can convert ordinary industrial hydrogen into high-purity hydrogen (purity >99.999%), and can be widely used in industrial production processes such as metallurgy, electronics, fuel cells, chemicals, and aerospace.

[0003] While hydrogen catalytic combustion offers unique advantages, it also has some drawbacks. First, it requires 24 / 7 operation, typically operating at low temperatures, even below freezing, due to the low outdoor temperatures. However, the initial start-up temperature and activity during hydrogen catalytic combustion are relatively high, limiting its application over a wide temperature range (room temperature or even below freezing). Second, water vapor readily adsorbs onto the active sites of the catalyst, making it difficult for the generated water to desorb from the catalyst surface, thus reducing catalyst activity. Finally, hydrogen catalytic combustion catalysts require large amounts of precious metals (Pt or Pd), resulting in high production costs. Therefore, developing a highly efficient and inexpensive hydrogen catalytic combustion catalyst is urgently needed.

[0004] CN113908831A discloses a method for preparing a hydrophobic catalyst for low-temperature catalytic combustion of hydrogen. The catalyst is an alumina-supported noble metal or an alloy thereof with a non-noble metal, which is then treated with a hydrophobic agent to obtain the hydrophobic catalyst for low-temperature catalytic combustion of hydrogen. Hydrophobic modification improves the catalyst's low-temperature activity and stability, allowing it to catalyze the hydrogen catalytic combustion process at temperatures ranging from -20°C to room temperature. However, the hydrophobic modification process is relatively complex, and hydrophobic reagents are expensive, increasing the preparation and usage costs.

[0005] CN114289071A discloses a water-resistant deoxygenation catalyst supported on a hydrophobic metal-organic framework material, its preparation method, and its application in hydrogen combustion deoxygenation. The active component is a noble metal, Pd or Pt. This hydrophobic catalyst can promptly remove water generated during the reaction, reducing the water residence time at low temperatures and preventing catalyst poisoning. However, this method uses organopalladium or organopallate salts as noble metal precursors with relatively high loading, resulting in high synthesis costs. Furthermore, the support material exhibits poor hydrothermal stability.

[0006] CN 113019434A uses molecular sieves to coat Pd, Pt, or Rh, which has the advantages of high atom utilization and low ignition temperature. However, this method uses a large amount of precious metals, increasing production costs. In addition, the carrier is non-hydrophobic, which may lead to water poisoning during the deoxygenation process. Summary of the Invention

[0007] The purpose of this invention is to overcome the problems of existing technologies, such as high start-up temperature and low initial activity in the hydrogen catalytic combustion process, which prevents its use in a wide temperature range; water generated at low temperatures is not easy to desorb from the catalyst surface, causing catalyst poisoning and deactivation; and the need to use a large amount of precious metal (Pt or Pd) catalyst in the catalytic combustion process, resulting in high production costs. This invention proposes for the first time a catalyst for burning hydrogen, which includes: silicon molecular sieve, tungsten and precious metal.

[0008] This invention discovers that modifying silicon molecular sieves through in-situ tungsten doping can improve the hydrophobicity of the support, thereby reducing the residence time of water on the catalyst surface and improving the deoxygenation efficiency of the catalyst at low temperatures or even below freezing, resulting in high initial activity. By controlling the preparation and calcination conditions, the dispersion of noble metals can be improved, thus reducing the amount of noble metals used. Furthermore, when this catalyst is applied in the catalytic process, the noble metals are less prone to sintering even after prolonged operation due to the confinement effect of the molecular sieve.

[0009] To achieve the above objectives, the present invention provides a catalyst for catalytic combustion and deoxygenation, the catalyst comprising: a silicon molecular sieve, tungsten, and a noble metal, wherein the contact angle of the catalyst is 90-130°.

[0010] A second aspect of the present invention provides a method for preparing the catalyst of the present invention, the method comprising: forming a solution to be crystallized from a silicon source, TPAOH, a tungsten source and a noble metal source, followed by crystallization, solid-liquid separation, washing, drying and calcination, wherein the calcination is carried out in an H2 atmosphere.

[0011] A third aspect of the present invention provides a method for catalytic combustion of hydrogen, the method comprising: catalytically combusting hydrogen and air as raw materials in the presence of the catalyst described in the present invention.

[0012] A fourth aspect of the present invention provides a method for removing oxygen from oxygen-containing hydrogen gas, the method comprising: catalytically deoxygenating the oxygen-containing hydrogen gas feedstock in the presence of the catalyst described in the present invention.

[0013] Through the above technical solution, the present invention has the following beneficial effects:

[0014] This invention is the first to discover that modifying silicon molecular sieves by in-situ doping with tungsten can improve the hydrophobicity of the support, thereby reducing the residence time of water on the catalyst surface and improving the deoxygenation efficiency of the catalyst at low temperatures or even below freezing, thus lowering the onset temperature. Furthermore, due to the confinement effect of the molecular sieve, the noble metal is less prone to sintering even after prolonged operation during the catalytic process. In a preferred embodiment, the dispersion of the noble metal active centers is improved by controlling the preparation and calcination conditions, thereby reducing the amount of noble metal used. Attached Figure Description

[0015] Figure 1 This refers to the catalyst contact angle in Example 3 of the present invention.

[0016] Figure 2 The contact angle of the catalyst in Comparative Example 1 is denoted as . Detailed Implementation

[0017] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0018] The present invention provides a catalyst for catalytic combustion and deoxygenation, the catalyst comprising: silicon molecular sieve, tungsten and noble metal, wherein the contact angle of the catalyst is 90-130°.

[0019] This invention discovers that modifying silicon molecular sieves with in-situ tungsten doping can improve the hydrophobicity of the support, thereby reducing the residence time of water on the catalyst surface and improving the catalytic efficiency of the catalyst at low temperatures or even below zero, resulting in high initial activity. In addition, due to the confinement effect of the molecular sieve, the noble metal is not easily sintered even after long-term operation.

[0020] According to a particularly preferred embodiment of the present invention, the noble metal is selected from at least one of Pt, Pd, and Ru. By employing the aforementioned preferred embodiment, the catalyst activity and lifetime can be further improved.

[0021] In this invention, the content of each component in the catalyst can be selected within a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a particularly preferred embodiment of the invention, the tungsten content is 0.3-3.1 wt% and the noble metal content is 0.02-0.4 wt% based on the total weight of the catalyst. The noble metal content of this invention is 0.02-0.4 wt%, which significantly reduces the amount of noble metal used compared to the content range of 0.1-2 wt% in the prior art.

[0022] In this invention, the silicon molecular sieve has no special requirements and is described by way of example, but does not limit the scope of the invention. According to a particularly preferred embodiment of the invention, the silicon molecular sieve has an MFI structure.

[0023] Catalysts possessing the aforementioned characteristics can all be used in this invention, and there are no special requirements for their preparation methods. This invention provides a method for preparing the catalyst, comprising: forming a crystallization solution from a silicon source, TPAOH, a tungsten source, and a noble metal source; followed by crystallization, solid-liquid separation, washing, drying, and calcination, wherein the calcination is carried out in an H2 atmosphere. The preparation method of this invention has the advantages of simple preparation process, low noble metal usage, and high catalyst activity. This invention discovers that modifying silicon molecular sieves by in-situ doping with tungsten can improve the hydrophobicity of the support, thereby reducing the residence time of water on the catalyst surface and improving the catalytic efficiency of the catalyst at low temperatures or even below zero, exhibiting high initial activity; furthermore, due to the confinement effect of the molecular sieve, the noble metal is not easily sintered even after long-term operation.

[0024] According to a preferred embodiment of the present invention, the preparation method includes: S1. mixing a silicon source, TPAOH, and a solvent, and then mixing the mixture with a tungsten source to form a mixed solution; S2. adding a noble metal source to the mixed solution to form the solution to be crystallized, transferring the solution to a reaction vessel for crystallization, separating the solid and liquid, washing, drying, and calcining, wherein the calcination is carried out in an H2 atmosphere.

[0025] In this invention, there are no special requirements for the step of forming the solution to be crystallized from silicon source, TPAOH, tungsten source and noble metal source. The main purpose is to obtain a uniform solution. For example, the materials can be mixed evenly by appropriate heating or dripping.

[0026] In this invention, the conditions and time for heating, slow dripping, and stirring are flexibly selected according to the type and amount of the substance. This is a well-known operating method for those skilled in the art, and will not be described in detail here.

[0027] In this invention, the conditions for solid-liquid separation are conventional technical means, which are well known to those skilled in the art, and will not be described in detail here.

[0028] In this invention, after the solid-liquid separation step and before the drying step, a washing step is required. The washing conditions are not particularly required and are well known to those skilled in the art. It is sufficient that the supernatant is neutral. The solvent and number of washing steps can be adjusted according to the actual operation. This invention will not elaborate further here.

[0029] In this invention, the drying conditions are conventional technical means, well known to those skilled in the art, and will not be described in detail here.

[0030] In this invention, the mixing conditions in step S1 are conventional technical means, well known to those skilled in the art, and can be selected according to actual operation. This invention will not elaborate further here.

[0031] In this invention, the conditions for solid-liquid separation are conventional technical means, which are well known to those skilled in the art, and will not be described in detail here.

[0032] In this invention, a heating rate of 0.05-1℃ / min is preferred. -1 Preferably, the temperature is 0.1-0.5℃ / min. -1 Heat the temperature to the roasting temperature and roast.

[0033] In this invention, the calcination temperature is preferably 300-650℃, and more preferably 500-600℃.

[0034] In this invention, the roasting time after heating to the roasting temperature can be selected within a wide range, preferably 1-8h, and more preferably 1-6h.

[0035] According to a particularly preferred embodiment of the present invention, the calcination is carried out in an H2 atmosphere, and the preferred calcination conditions include: a hydrogen flow rate of 50-200 mL / min. -1 Below, at 0.05-1℃min -1 The temperature is increased to 300-650℃, and calcined for 1-8 hours. The preferred heating rate is 0.1-0.5℃ / min. -1The preferred calcination temperature is 500-600℃, and the preferred calcination time is 1-6 hours. By adopting the aforementioned preferred embodiment, the accumulation of precious metals due to high temperature can be prevented, thereby further improving the catalytic activity of the precious metals.

[0036] According to a preferred embodiment of the present invention, the molar ratio of silicon source: TPAOH: tungsten source: H2O: noble metal source is 1:x:y:z:n; x = 0.1-0.6, y = 0.0001-0.01, z = 30-120, n = 0.00005-0.0023, wherein the silicon source is calculated as SiO2, the tungsten source is calculated as W, and the noble metal source is calculated as noble metal.

[0037] In this invention, the silicon source has no special requirements and is described by way of example, but does not limit the scope of the invention. According to a preferred embodiment of the invention, the silicon source is selected from one or more of silicone grease, silica sol, silica gel and fumed silica, preferably silicone grease, and more preferably TEOS.

[0038] In this invention, the tungsten source has no special requirements and is described by way of example, but does not limit the scope of the invention. According to a preferred embodiment of the invention, the compound in the tungsten source is selected from at least one of sodium tungstate, ammonium metatungstate and ammonium paratungstate.

[0039] In this invention, the compounds in the noble metal source are not specifically required; the examples provided are exemplary but do not limit the scope of the invention. According to a preferred embodiment of the invention, the compounds in the noble metal source are selected from at least one of chloroplatinic acid, platinum acetylacetonate, dichlorotetramineplatinum, palladium acetylacetonate, palladium chloride, palladium nitrate, palladium acetate, palladium acetylacetonate, diammonium palladium tetrachloride, dichlorotetraminepalladium, ruthenium chloride, and ruthenium acetylacetonate. By employing the aforementioned preferred embodiments, the catalytic activity and lifetime of the noble metal can be further improved.

[0040] In this invention, there are no special requirements for the crystallization conditions in step S2.

[0041] According to a preferred embodiment of the present invention, the crystallization temperature is 100-220°C.

[0042] According to a preferred embodiment of the present invention, the crystallization time is 2-30 hours, preferably 8-26 hours.

[0043] This invention provides a catalyst prepared by the method of this invention.

[0044] In this invention, the dispersion of the active centers of precious metals is improved by controlling the preparation and calcination conditions, thereby reducing the amount of precious metals used.

[0045] The present invention provides a method for catalytic combustion of hydrogen, the method comprising: catalytically combusting hydrogen and air as raw materials in the presence of the catalyst described in the present invention.

[0046] In this invention, there are no special requirements for the conditions of the catalytic combustion reaction.

[0047] According to a preferred embodiment of the present invention, the catalytic combustion reaction is carried out in a fixed bed.

[0048] According to a preferred embodiment of the present invention, the catalytic combustion reaction pressure is 0.1-4 MPa, for example, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, etc. 0.1 MPa is used as an example in the embodiments to illustrate the advantages of the present invention.

[0049] According to a preferred embodiment of the present invention, the volume hourly space velocity of the feedstock in the catalytic combustion reaction is 1000-50000 h⁻¹. -1 Preferably 8000-40000h -1 .

[0050] According to a preferred embodiment of the present invention, the catalytic combustion reaction temperature is -20℃ to 40℃, preferably -10℃ to 30℃, for example -10℃, 0℃, 10℃, 20℃, 30℃, etc.

[0051] According to a preferred embodiment of the present invention, the hydrogen concentration ranges from 1 to 10 v / v%.

[0052] The present invention provides a method for removing oxygen from oxygen-containing hydrogen gas, the method comprising: catalytically deoxygenating the oxygen-containing hydrogen gas feedstock in the presence of the catalyst described in the present invention.

[0053] In this invention, there are no special requirements for the conditions of the catalytic combustion deoxygenation reaction.

[0054] According to a preferred embodiment of the present invention, the catalytic combustion deoxygenation reaction is carried out in a fixed bed.

[0055] According to a preferred embodiment of the present invention, the catalytic combustion deoxygenation reaction pressure is 0.1-4 MPa, for example, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, etc. In the examples, 0.1 MPa is used as an example to illustrate the advantages of the present invention.

[0056] According to a preferred embodiment of the present invention, the volume hourly space velocity (VHSV) of the feedstock for the catalytic combustion deoxygenation reaction is 1000-10000 h⁻¹. -1 Preferably 3000-8000h -1 .

[0057] According to a preferred embodiment of the present invention, the catalytic combustion deoxygenation reaction temperature is -20℃ to 200℃, preferably -10℃ to 80℃, such as -10℃, 0℃, 20℃, 30℃, 40℃, 50℃, 60℃, 70℃, etc.

[0058] According to a preferred embodiment of the present invention, the oxygen concentration in the oxygen-containing hydrogen gas from the catalytic combustion deoxygenation reaction ranges from 1 to 5000 ppm, preferably from 1000 to 5000 ppm.

[0059] The present invention will be described in detail below through examples. The elemental content of the samples was determined by the ICP-OES method.

[0060] The contact angle is measured using a contact angle meter. When testing the water contact angle, the sample is typically fixed to the surface of a glass slide, and the droplet volume is 2 μL.

[0061] Example 1

[0062] In this embodiment, the feed composition meets the following conditions: 1SiO2:0.1TPAOH:0.001Na2WO4:0.00006H2PtCl6:30H2O;

[0063] Catalyst preparation: TEOS was slowly added to a mixed solution of TPAOH (30 wt% aqueous solution) and H2O, and stirred for 6 h. Na2WO4 was dissolved in water and slowly added dropwise, stirring for 2 h. Then, H2PtCl6 was dissolved in water and slowly added dropwise, stirring for 2 h. Finally, the resulting mixture was poured into a stainless steel reactor lined with polytetrafluoroethylene, mechanically sealed, and crystallized at 100℃ for 26 h. After the reaction, the reactor was removed, rapidly cooled, and the milky white liquid inside was repeatedly centrifuged and washed until the supernatant was neutral. It was then dried at 120℃ for 12 h. Then, the white powder was heated at 500℃ under hydrogen (hydrogen flow rate 50 mL / min). -1 Pt-WS-1 molecular sieve powder was obtained by calcination for 1 hour under a heating atmosphere with a heating rate of 0.5℃ / min. -1 The prepared catalyst was analyzed by ICP, and it was found that the W content was 0.30%, the Pt content was 0.02%, and the contact angle was 96.5°.

[0064] Catalyst performance evaluation:

[0065] (1) The performance evaluation of hydrogen catalytic combustion reaction was carried out in a fixed bed. The tail gas was detected by a tail gas analyzer. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was 30 °C, the feed gas was a mixture of hydrogen and air, the hydrogen concentration was 10 v / v%, and the volume hourly space velocity was 40000 h⁻¹. -1 The hydrogen conversion rate was measured 30 minutes after the reaction started;

[0066] (2) Performance evaluation of catalytic deoxygenation reaction in a fixed bed was conducted. The tail gas was detected by an O2 detector. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was 80 °C, the feed gas was a mixture of hydrogen and oxygen with an oxygen concentration of 5000 ppm and a volume hourly space velocity of 8000 h⁻¹. -1 The reaction was monitored 30 minutes after it started. The oxygen concentration in the exhaust gas was 0.9 ppm, and the hydrogen concentration was 99.99991%.

[0067] Example 2

[0068] In this embodiment, the feed composition meets the following conditions: 1SiO2:0.2TPAOH:0.002Na2WO4:0.0002Pt(NH3)4Cl2:50H2O;

[0069] Catalyst preparation: Silica sol (40 wt%) was slowly added to a mixed solution of TPAOH and H2O, and stirred for 12 h. Na2WO4 was dissolved in water and slowly added dropwise, stirring for 4 h. Then, Pt(NH3)4Cl2 was dissolved in water and slowly added dropwise, stirring for 4 h. Finally, the resulting mixture was poured into a stainless steel reactor lined with polytetrafluoroethylene, mechanically sealed, and crystallized at 120 °C for 20 h. After the reaction, the reactor was removed, rapidly cooled, and the milky white liquid inside was repeatedly centrifuged and washed until the supernatant was neutral. It was then dried at 120 °C for 12 h. The white powder was then heated at 550 °C under hydrogen (hydrogen flow rate 100 mL / min). -1 Pt-WS-1 molecular sieve powder was obtained by calcination for 2 hours under a heating atmosphere at a heating rate of 0.5℃ / min. -1 The prepared catalyst was analyzed by ICP, and the results showed that the W content was 0.62%, the Pt content was 0.041%, and the contact angle was 105.4°.

[0070] Catalyst performance evaluation:

[0071] (1) The performance evaluation of hydrogen catalytic combustion reaction was carried out in a fixed bed. The tail gas was detected by a tail gas analyzer. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was 20 °C, the feed gas was a mixture of hydrogen and air, the hydrogen concentration was 8 v / v%, and the volume hourly space velocity was 30000 h⁻¹. -1 The hydrogen conversion rate was measured 30 minutes after the reaction started;

[0072] (2) Performance evaluation of hydrogen catalytic deoxygenation reaction in a fixed bed. The tail gas was detected by an O2 detector. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was 60 °C, the feed gas was a mixture of hydrogen and oxygen with an oxygen concentration of 3000 ppm and a volume hourly space velocity of 6000 h⁻¹.-1 The reaction was monitored 30 minutes after it started. The oxygen concentration in the exhaust gas was 0.6 ppm, and the hydrogen concentration was 99.99994%.

[0073] Example 3

[0074] In this embodiment, the feed composition meets the following criteria: 1SiO2:0.3TPAOH:0.00042ammonium metatungstate (H 28 N6O 41 W 12 ):0.0006PdCl2:70H2O;

[0075] Catalyst preparation: Fumed silica was added to a mixed solution of TPAOH and H2O and stirred for 18 h. Ammonium metatungstate was dissolved in water and slowly added dropwise while stirring for 8 h. Then, PdCl2 was dissolved in water and slowly added dropwise while stirring for 8 h. Finally, the resulting synthesis solution was poured into a stainless steel reactor lined with polytetrafluoroethylene, mechanically sealed, and crystallized at 140 °C for 18 h. After the reaction, the reactor was removed, rapidly cooled, and the milky white liquid inside was repeatedly centrifuged and washed until the supernatant was neutral. It was then dried at 120 °C for 12 h. Then, the white powder was heated at 550 °C in hydrogen gas (hydrogen flow rate 150 mL / min). -1 Pd-WS-1 molecular sieve powder was obtained by calcination for 4 hours under a heating atmosphere at a heating rate of 0.5℃ / min. -1 The prepared catalyst was analyzed by ICP, and the results showed that the W content was 1.51%, the Pt content was 0.10%, and the contact angle was 119°. Figure 1 The catalyst contact angle of Example 3 is shown;

[0076] Catalyst performance evaluation:

[0077] (1) The performance evaluation of hydrogen catalytic combustion reaction was carried out in a fixed bed. The tail gas was detected by a tail gas analyzer. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was 10 °C, the feed gas was a mixture of hydrogen and air, the hydrogen concentration was 6 v / v%, and the volume hourly space velocity was 20000 h⁻¹. -1 The hydrogen conversion rate was measured 30 minutes after the reaction started;

[0078] (2) Performance evaluation of hydrogen catalytic deoxygenation reaction in a fixed bed was conducted. The tail gas was detected by an O2 detector. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was 30 °C, the feed gas was a mixture of hydrogen and oxygen with an oxygen concentration of 1000 ppm, and the volume hourly space velocity was 5000 h⁻¹. -1 The reaction was monitored 30 minutes after it started. The oxygen concentration in the exhaust gas was 0.4 ppm, and the hydrogen concentration was 99.99996%.

[0079] Example 4

[0080] In this embodiment, the feed composition meets the following requirements: 1SiO2:0.4TPAOH:0.00067ammonium paratungstate ((NH4) 10 W 12 O 41 ·5H2O):0.0011Pd(NO3)2:90H2O;

[0081] Catalyst preparation: TEOS was slowly added to a mixed solution of TPAOH and H2O and stirred for 24 h. Ammonium paratungstate was dissolved in water and slowly added dropwise while stirring for 16 h. Then, a Pd(NO3)2 solution (Pd mass fraction 18.36%) was slowly added dropwise while stirring for 16 h. Finally, the resulting synthesis solution was poured into a stainless steel reactor lined with polytetrafluoroethylene, mechanically sealed, and crystallized at 160 °C for 12 h. After the reaction, the reactor was removed, rapidly cooled, and the milky white liquid inside was repeatedly centrifuged and washed until the supernatant was neutral. It was then dried at 120 °C for 12 h. Then, the white powder was heated at 600 °C under hydrogen (hydrogen flow rate 200 mL / min). -1 Pt-WS-1 molecular sieve powder was obtained by calcination for 6 hours under a heating atmosphere at a heating rate of 0.5℃ / min. -1 The prepared catalyst was analyzed by ICP, and the results showed that the W content was 2.51%, the Pd content was 0.19%, and the contact angle was 124.3°.

[0082] Catalyst performance evaluation:

[0083] (1) The performance evaluation of hydrogen catalytic combustion reaction was carried out in a fixed bed. The tail gas was detected by a tail gas analyzer. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was -10℃, the feed gas was a mixture of hydrogen and air, the hydrogen concentration was 4 v / v%, and the volume hourly space velocity was 10000 h⁻¹. -1 The hydrogen conversion rate was measured 30 minutes after the reaction started;

[0084] (2) Performance evaluation of hydrogen catalytic deoxygenation reaction in a fixed bed was conducted. The tail gas was detected by an O2 detector. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was 20 °C, the feed gas was a mixture of hydrogen and oxygen with an oxygen concentration of 2000 ppm, and the volume hourly space velocity was 3000 h⁻¹. -1 The reaction was monitored 30 minutes after it started. The oxygen concentration in the exhaust gas was 0.3 ppm, and the hydrogen concentration was 99.99997%.

[0085] Example 5

[0086] In this embodiment, the feed composition meets the following requirements: 1SiO2:0.5TPAOH:0.01Na2WO4:0.0023RuCl3:110H2O;

[0087] Catalyst preparation: TEOS was slowly added to a mixed solution of TPAOH and H2O and stirred for 48 h. Na2WO4 was dissolved in water and slowly added dropwise while stirring for 24 h. Then RuCl3 was dissolved in water and slowly added dropwise while stirring for 24 h. Finally, the resulting synthesis solution was poured into a stainless steel reactor lined with polytetrafluoroethylene, mechanically sealed, and crystallized at 200 °C for 8 h. After the reaction, the reactor was removed, rapidly cooled, and the milky white liquid inside was repeatedly centrifuged and washed until the supernatant was neutral. It was then dried at 120 °C for 12 h. Then, the white powder was heated at 650 °C under hydrogen (hydrogen flow rate 50 mL / min). -1 Pt-WS-1 molecular sieve raw powder was obtained by calcination for 8 hours under a heating atmosphere at a heating rate of 0.5℃ / min. -1 The catalyst prepared was analyzed by ICP, and it was found that the W content was 3.10%, the Ru content was 0.39%, and the contact angle was 127.4°.

[0088] Catalyst performance evaluation:

[0089] (1) The performance evaluation of hydrogen catalytic combustion reaction was carried out in a fixed bed. The tail gas was detected by a tail gas analyzer. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was 10 °C, the feed gas was a mixture of hydrogen and air, the hydrogen concentration was 2 v / v%, and the volume hourly space velocity was 8000 h⁻¹. -1 The hydrogen conversion rate was measured 30 minutes after the reaction started;

[0090] (2) Performance evaluation of hydrogen catalytic deoxygenation reaction in a fixed bed was conducted. The tail gas was detected by an O2 detector. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was -10℃, the feed gas was a mixture of hydrogen and oxygen with an oxygen concentration of 1000 ppm, and the volume hourly space velocity was 3000 h⁻¹. -1 The reaction was monitored 30 minutes after it started. The oxygen concentration in the exhaust gas was 0.6 ppm, and the hydrogen concentration was 99.99994%.

[0091] Comparative Example 1

[0092] In this embodiment, the feed composition meets the following criteria: 1SiO2:0.3TPAOH:0.0006PdCl2:70H2O;

[0093] Catalyst preparation: Under vigorous stirring, fumed silica was slowly added to a mixed solution of TPAOH and H2O and stirred for 8 hours. Then, PdCl2 was dissolved in water and slowly added dropwise, stirring for 8 hours. Finally, the resulting synthesis solution was poured into a stainless steel reactor lined with polytetrafluoroethylene, mechanically sealed, and crystallized at 140℃ for 18 hours. After the reaction, the reactor was removed, rapidly cooled, and the milky white liquid inside was repeatedly centrifuged and washed until the supernatant was neutral. It was then dried at 120℃ for 12 hours. The white powder was then heated at 550℃ under hydrogen (hydrogen flow rate 150 mL / min). -1 Pd-S-1 molecular sieve powder was obtained by calcination for 4 hours under a heating atmosphere at a heating rate of 0.5℃ / min. -1 The prepared catalyst was analyzed by ICP, which showed that the Pd content was 0.10% and the contact angle was 80°. Figure 2 The catalyst contact angle of Comparative Example 1 is shown;

[0094] Catalyst performance evaluation:

[0095] (1) The performance evaluation of hydrogen catalytic combustion reaction was carried out in a fixed bed. The tail gas was detected by a tail gas analyzer. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was 10 °C, the feed gas was a mixture of hydrogen and air, the hydrogen concentration was 6 v / v%, and the volume hourly space velocity was 20000 h⁻¹. -1 The hydrogen conversion rate was measured 30 minutes after the reaction began;

[0096] (2) The performance of the catalyst in the hydrogen catalytic deoxygenation reaction in a fixed bed was evaluated. The tail gas was detected by an O2 detector. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was 30 °C, the feed gas was a mixture of hydrogen and oxygen with an oxygen concentration of 1000 ppm and a volume hourly space velocity of 5000 h⁻¹. -1 The reaction was monitored 30 minutes after it started. The oxygen concentration in the exhaust gas was 100.5 ppm, and the hydrogen concentration was 99.98995%.

[0097] Comparative Example 2

[0098] Preparation of S-1 molecular sieve: In this embodiment, the feed composition meets the following requirements: 1SiO2:0.3TPAOH:70H2O.

[0099] Fumed silica was slowly added to a mixed solution of TPAOH and H2O and stirred for 18 hours. The resulting synthesis solution was poured into a stainless steel reactor lined with polytetrafluoroethylene (PTFE), mechanically sealed, and crystallized at 140°C for 18 hours. After the reaction, the reactor was removed, rapidly cooled, and the milky white liquid inside was repeatedly centrifuged and washed until the supernatant was neutral. The supernatant was then dried at 120°C for 12 hours. The white powder was then calcined at 550°C in air for 4 hours at a heating rate of 3°C / min to obtain S-1 molecular sieve raw powder. -1 .

[0100] Catalyst preparation: Palladium nitrate solution (Pd mass fraction 18.36%) and ammonium tungstate hydrate were dissolved in water, and then Pd and W were impregnated in S-1 support by equal volume impregnation. ICP analysis of the prepared catalyst revealed a W content of 1.54%, a Pt content of 0.10%, and a contact angle of 81°.

[0101] Catalyst performance evaluation:

[0102] (1) The performance evaluation of hydrogen catalytic combustion reaction was carried out in a fixed bed. The tail gas was detected by a tail gas analyzer. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was 10 °C, the feed gas was a mixture of hydrogen and air, the hydrogen concentration was 6 v / v%, and the volume hourly space velocity was 20000 h⁻¹. -1 The hydrogen conversion rate was measured 30 minutes after the reaction began.

[0103] (2) Performance evaluation of hydrogen catalytic deoxygenation reaction in a fixed bed was conducted. The tail gas was detected by an O2 detector. The catalyst dosage was 5 mL, the reaction pressure was 0.1 MPa, the reaction temperature was 30 °C, the feed gas was a mixture of hydrogen and oxygen with an oxygen concentration of 1000 ppm, and the volume hourly space velocity was 5000 h⁻¹. -1 The reaction was monitored 30 minutes after it began. The oxygen concentration in the exhaust gas was 800 ppm, and the hydrogen concentration was 99.92%.

[0104] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for removing oxygen from oxygen-containing hydrogen gas, characterized in that, The method includes: catalytically deoxygenating an oxygen-containing hydrogen feedstock in the presence of a catalyst, wherein the oxygen concentration in the oxygen-containing hydrogen ranges from 1 to 5000 ppm; The catalyst comprises: a silicon molecular sieve, tungsten, and a noble metal, wherein the contact angle of the catalyst is 90-130°; the tungsten content is 0.3-0.62 wt% and the noble metal content is 0.02-0.041 wt% based on the total weight of the catalyst. The method for preparing the catalyst includes: A solution to be crystallized is formed by silicon source, TPAOH, tungsten source and noble metal source, followed by crystallization, solid-liquid separation, washing, drying and calcination, wherein the calcination is carried out in H2 atmosphere.

2. The method according to claim 1, wherein, The precious metal is selected from at least one of Pt, Pd, and Ru; and / or The silicon molecular sieve has an MFI structure.

3. The method according to claim 1, wherein, The method for preparing the catalyst includes: S1. After mixing the silicon source and TPAOH, it is then mixed with the tungsten source to form a mixed solution; S2. Add the precious metal source to the mixed solution to form the solution to be crystallized, transfer it to the reaction vessel for crystallization, separate the solid and liquid, dry, and calcine. The calcification is carried out in an H2 atmosphere.

4. The method according to claim 3, wherein, Calcination conditions include: a hydrogen flow rate of 50-200 mL / min. -1 Below, at 0.05-1 ℃min 1 The heating rate is increased to 300-650 ℃, and the calcination is carried out for 1-8 hours; and / or The molar ratio of silicon source : TPAOH : Tungsten source : H2O : Noble metal source is 1 : x : y : z : n, where silicon source is SiO2, tungsten source is W, and noble metal source is noble metal. in, x=0.1-0.6， y=0.0001-0.01， z=30-120， n=0.00005-0.0023； and / or Crystallization conditions include a temperature of 100-220 °C and / or a time of 2-30 h.

5. The method according to claim 3, wherein, The silicon source is selected from one or more of silicone grease, silica sol, and fumed silica; and / or The compound in the tungsten source is selected from at least one of sodium tungstate, ammonium metatungstate, and ammonium paratungstate; and / or The compound in the noble metal source is selected from at least one of chloroplatinic acid, platinum acetylacetonate, dichlorotetramineplatinum, palladium acetylacetonate, palladium chloride, palladium nitrate, palladium acetate, palladium acetylacetonate, diammonium palladium tetrachloride, dichlorotetraminepalladium, ruthenium chloride, and ruthenium acetylacetonate.

6. The method according to claim 1, wherein, Catalytic deoxygenation reactions are carried out in a fixed bed; and / or Catalytic deoxygenation operating conditions include: The pressure is 0.1-4 MPa; and / or the feed volume hourly space velocity is 1000-10000 h⁻¹. 1 ; and / or the temperature is -20℃ to 200 °C.

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