Catalyst for ultrahigh-temperature water-gas shift reaction as well as preparation method and application of catalyst

Abstract

The invention relates to the field of a water-gas shift hydrogen production process, in particular to a catalyst for an ultrahigh-temperature water-gas shift reaction as well as a preparation method and application of the catalyst. The catalyst comprises a first component and a second component, the first component comprises an active component, an auxiliary agent and a carrier; the active component comprises Fe3O4 (ferroferric oxide); the auxiliary agent comprises CeO2; the carrier is prepared from Al2O3; and the second component comprises CaO, Al2O3 and Ca12Al14O33, and the second component comprises CaO, Al2O3 and The catalyst prepared by the invention contains double sites of catalysis and adsorption, can avoid slow kinetics at low temperature, breaks thermodynamic limitation at high temperature, directly converts and gasifies synthesis gas at ultrahigh temperature in one step by joining the outlet temperature of a gasifier, fundamentally simplifies the traditional water-gas shift hydrogen production process, and improves the hydrogen production efficiency. After the reaction, the CO conversion rate reaches 90.0% at most, the H2 purity reaches 96.0%, and the conversion reaction efficiency is remarkably improved.

Description

Technical Field

[0001] The present invention relates to the field of water-gas shift hydrogen production technology, and in particular to a catalyst for ultra-high temperature water-gas shift reaction, and a preparation method and application thereof. Background Art

[0002] Currently, due to the increasing greenhouse gas emissions, growing energy demand and CO2 capture strategies, the climate change situation is severe and people urgently need to switch to clean and efficient fuels. Therefore, academia and industry are paying attention to the next generation energy system based on hydrogen (H2). Hydrogen has a very high energy content (120 MJ / kg) and is considered to be a promising energy carrier. The water gas shift reaction is one of the main processes for large-scale production of H2 in the industrial field. In order to improve the conversion rate of CO, multi-stage processes and expensive catalysts are usually used.

[0003] In industry, in order to overcome thermodynamic limitations and further improve CO conversion, the water gas shift process is usually carried out in two steps: first, a high-temperature water gas shift (350-450°C) reaction is carried out on a commercial Fe-Cr catalyst; then a low-temperature water gas shift (180-250°C) reaction is carried out on a commercial Cu-Zn-Al catalyst. However, the multi-stage process results in high energy consumption and high costs. At the same time, the high-temperature shift catalyst contains chromium, which imposes great restrictions on transportation, use and disposal, and even brings serious harm to the human body and the environment. In addition, excess steam is required to maintain the stability of the catalyst.

[0004] Currently, the main limiting factor for the utilization of waste-derived syngas is that the syngas is contaminated by tar and high concentration of CO (about 38%). Therefore, before entering the conversion system, the syngas usually needs to undergo a series of treatments such as cooling, decoking, and pressurization, and then heated to the temperature required for the conversion reaction. In addition, high concentrations of CO require multi-stage conversion processes for conversion, which undoubtedly increases the complexity, energy consumption and cost of the process. As the organic solid waste gasification process develops towards pressurization and low tar, accompanied by pollutant control and high-temperature gas purification technology, the research on ultra-high temperature conversion process is in line with the development trend of gasification technology.

[0005] Therefore, there is an urgent need to develop chromium-free green catalysts with shift activity and stability under high CO concentration conditions at high temperature (500-700°C) and low H2O / CO ratio (<3). In recent years, research on high-temperature shift catalysts has increasingly focused on the development of new catalysts, such as chromium-free iron-based catalysts or iron-free catalysts. However, there is a lack of comprehensive research and reports on unconventional processes involving unconventional feedstocks (such as waste-derived syngas). Summary of the invention

[0006] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the present invention provides a catalyst for ultra-high temperature water-gas shift reaction, a preparation method and application thereof, the catalyst contains dual sites of catalysis and adsorption, can avoid slow kinetics at low temperature, and break the thermodynamic limitation at high temperature, by connecting the gasifier outlet temperature to directly convert the gasified synthesis gas in the ultra-high temperature step, fundamentally simplifying the traditional water-gas shift hydrogen production process. After the reaction, the CO conversion rate reaches up to 90.0%, and the H2 purity reaches 96.0%, which significantly improves the efficiency of the shift reaction.

[0007] To this end, the first aspect of the present invention provides a catalyst for ultra-high temperature water gas shift reaction, the catalyst comprising a first component and a second component;

[0008] The first component includes an active component, an adjuvant, and a carrier;

[0009] The active component includes Fe3O4; the auxiliary agent includes CeO2; the carrier includes Al2O3;

[0010] The second component includes CaO, Al2O3 and Ca 12 Al 14 O 33 .

[0011] The catalyst provided by the present invention is simple to prepare and low in cost. It contains dual sites of catalysis and adsorption, can simultaneously promote CO conversion and remove generated CO2, can break the contradiction between slow kinetics at low temperatures and thermodynamic equilibrium at high temperatures, further improve conversion efficiency and realize in-situ decarbonization to prepare high-purity hydrogen.

[0012] According to an embodiment of the present invention, the mass ratio of the active component, the auxiliary agent and the carrier in the first component satisfies (75-85):(5-15):10.

[0013] According to an embodiment of the present invention, the mass ratio of the first component to the catalyst is 20%-40%.

[0014] According to an embodiment of the present invention, the molar ratio of the elements Ca / Al in the second component is (90-60):(10-40).

[0015] According to an embodiment of the present invention, the particle size of the catalyst is 0.2 mm-1 mm.

[0016] The second aspect of the present invention provides a method for preparing the catalyst according to the first aspect, comprising the following steps:

[0017] Preparing a first mixed solution containing an iron salt, a cerium salt and a first aluminum salt, adjusting the pH value of the first mixed solution to 9-10, and obtaining a first component precursor through a precipitation reaction;

[0018] preparing a second mixed solution containing a calcium salt and a second aluminum salt, and drying the solution to obtain a second component precursor;

[0019] The first component precursor and the second component precursor are calcined and ground respectively to obtain the first component and the second component;

[0020] The first component and the second component are mixed to obtain the catalyst.

[0021] The catalyst for the ultra-high temperature water-gas shift reaction can be prepared by the preparation method provided by the present invention. The preparation method has the advantages of simple preparation and low cost.

[0022] According to an embodiment of the present invention, the iron salt comprises iron nitrate.

[0023] According to an embodiment of the present invention, the cerium salt includes cerium nitrate.

[0024] According to an embodiment of the present invention, the first aluminum salt comprises aluminum nitrate.

[0025] According to an embodiment of the present invention, the calcium salt includes calcium acetate.

[0026] According to an embodiment of the present invention, the second aluminum salt includes aluminum nitrate nonahydrate.

[0027] According to an embodiment of the present invention, the drying temperature is 100°C-120°C.

[0028] According to an embodiment of the present invention, the drying time is 4h-6h.

[0029] According to an embodiment of the present invention, the calcination temperature is independently 700°C-900°C.

[0030] According to an embodiment of the present invention, the calcination time is independently 4h-6h.

[0031] The third aspect of the present invention provides an application of the catalyst described in the first aspect or the catalyst obtained according to the preparation method described in the second aspect in an ultra-high temperature water gas shift reaction.

[0032] A fourth aspect of the present invention provides a device for producing hydrogen from water-gas shift of synthesis gas, the device comprising a reaction unit and a regeneration unit, the reaction unit comprising a reaction device and a separation device, the regeneration unit comprising a regeneration device;

[0033] The reaction device comprises a first reaction zone and a second reaction zone connected to each other, the second reaction zone is located above the first reaction zone, the diameter of the first reaction zone is greater than or equal to the diameter of the second reaction zone, and the reaction device is used for hydrogen production and CO2 removal by water-gas shift of synthesis gas;

[0034] A gas inlet is provided at the bottom of the first reaction zone for providing a mixed gas to the reaction device, wherein the mixed gas includes synthesis gas and water vapor;

[0035] The bottom side wall of the second reaction zone is provided with a feed port for providing the catalyst described in the first aspect or the catalyst obtained according to the preparation method described in the second aspect to the reaction device;

[0036] The separation device is connected to the top of the second reaction zone in the reaction device and is used to separate the product gas and the used catalyst, wherein the product gas includes hydrogen and impurities;

[0037] The regeneration device is connected to the separation device and the reaction device respectively, and is used for recovering the used catalyst and regenerating the catalyst.

[0038] The reaction device provided by the present invention includes a first reaction zone with a wider bottom and a second reaction zone with a narrower top, which increases the contact time between the catalyst and the mixed gas to achieve sufficient reaction, and the two reaction zones form a similar two-stage transformation, which can achieve further fine transformation and fully utilize the reaction heat through heat exchange and temperature control.

[0039] According to an embodiment of the present invention, the regeneration unit further comprises a connected heat exchange device and a CO2 storage device, wherein the heat exchange device is connected to the top of the regeneration device, and the CO2 storage device is connected to the bottom of the regeneration device.

[0040] According to an embodiment of the present invention, the equipment further comprises a purification unit, which is connected to the separation device and is used to collect the product gas and improve the purity of hydrogen in the product gas.

[0041] According to an embodiment of the present invention, the purification unit includes a quenching device, an acid removal device, a gas-liquid separation device, a filtering device and a H2 storage device which are connected in sequence.

[0042] A fifth aspect of the present invention provides a process for producing hydrogen by water-gas shift of synthesis gas, the process using the apparatus described in the fourth aspect, comprising the following steps:

[0043] delivering the catalyst into the reaction device through the feed port;

[0044] The mixed gas enters the reaction device through the gas inlet, flows upward through the first reaction zone and the second reaction zone in sequence, undergoes a shift reaction under the action of the catalyst, and obtains a shift gas;

[0045] The shifted gas enters the separation device to separate the product gas and the used catalyst in the shifted gas, the product gas is discharged from the top of the separation device, and the used catalyst enters the regeneration device from the bottom of the separation device;

[0046] CO2 is introduced into the regeneration device from bottom to top, and the used catalyst is decomposed to obtain regenerated catalyst and CO2, wherein CO2 is discharged from the top of the regeneration device, and the regenerated catalyst enters the reaction device from the bottom of the regeneration device for recycling.

[0047] The process provided by the present invention is simple to operate and realizes the recycling of catalysts, while matching the synthesis gas temperature at the gasification outlet, greatly saving costs and improving production efficiency. As the organic solid waste gasification process develops in the direction of pressurization and low tar, the ultra-high temperature conversion process has broad development prospects.

[0048] According to an embodiment of the present invention, the reaction temperatures of the first reaction zone and the second reaction zone are the same, both of which are 550°C-650°C.

[0049] According to an embodiment of the present invention, the pressure of the shift reaction is 0.1Mpa-0.6Mpa.

[0050] According to an embodiment of the present invention, the synthesis gas includes 30%-40% CO, 25%-35% CO2, ≤5% CH4 and 15%-25% H2 by volume.

[0051] According to an embodiment of the present invention, the volume ratio of water vapor in the mixed gas to CO in the synthesis gas is (1-3):1.

[0052] According to an embodiment of the present invention, the tar content in the synthesis gas is less than 1g / Nm 3 , the temperature is 450℃-650℃.

[0053] According to an embodiment of the present invention, the temperature of the mixed gas is not less than 450°C.

[0054] According to an embodiment of the present invention, the temperature of the air inlet is 500°C-650°C.

[0055] According to an embodiment of the present invention, the decomposition temperature of the used catalyst is 800°C-900°C.

[0056] According to an embodiment of the present invention, the process further comprises: passing the product gas discharged from the top of the separation device into the purification unit, and obtaining hydrogen through cooling, deacidification, gas-liquid separation, and filtration.

[0057] The beneficial effects of the present invention compared to the prior art are as follows:

[0058] (1) The bifunctional catalyst disclosed in the present invention is simple to prepare and low in cost. It has the functions of catalytic conversion and CO2 removal at the same time, which can break the contradiction between slow kinetics at low temperature and thermodynamic equilibrium at high temperature, further improve the conversion efficiency and realize in-situ decarbonization to prepare high-purity hydrogen.

[0059] (2) In the equipment provided by the present invention, the reaction device includes a first reaction zone with a wider bottom and a second reaction zone with a narrower top, which increases the contact time between the catalyst and the reaction gas and achieves a full reaction. The reaction occurring in the reaction device can be expressed as CO+H2O+CaO=H2+CaCO3, and the two reaction zones form a similar two-stage transformation, which can achieve further fine transformation and fully utilize the reaction heat through heat exchange and temperature control.

[0060] (3) The process flow disclosed in the present invention is simple to operate and realizes the recycling of catalysts. At the same time, it matches the synthesis gas temperature at the gasification outlet, greatly saving costs and improving production efficiency. As the organic solid waste gasification process develops in the direction of pressurization and low tar, the ultra-high temperature conversion process has broad development prospects.

[0061] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0063] Figure 1 The schematic diagram of the process for producing hydrogen by water-gas shift of synthesis gas provided by the present invention is shown;

[0064] Figure 2 The process flow chart of hydrogen production by synthesis gas water gas shift according to Example 1 of the present invention is shown.

[0065] Reference numerals:

[0066] Reaction unit 100, reaction device 110, first reaction zone 111, second reaction zone 112, separation device 120, regeneration unit 200, regeneration device 210, heat exchange device 220, CO2 storage device 230, purification unit 300, quenching device 310, acid removal device 320, gas-liquid separation device 330, filtering device 340, H2 storage device 350. DETAILED DESCRIPTION

[0067] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be understood as limiting the present invention.

[0068] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. Further, in the description of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

[0069] The endpoints and any values ​​of the ranges disclosed in this article 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 each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0070] In order to make the present invention more easily understood, certain technical and scientific terms are specifically defined below. Unless otherwise clearly defined elsewhere in this document, all other technical and scientific terms used herein have the meanings commonly understood by those skilled in the art to which the present invention belongs.

[0071] In this document, the terms “include” or “comprising” are open expressions, that is, including the contents specified in the present invention but not excluding other contents.

[0072] As used herein, the terms "optionally", "optional" or "optionally" generally mean that the subsequently described event or circumstance may but need not occur, and that the description includes instances where the event or circumstance occurs and instances where it does not.

[0073] According to an embodiment of the present invention, a first aspect of the present invention provides a catalyst for ultra-high temperature water gas shift reaction, wherein the catalyst comprises a first component and a second component;

[0074] The first component includes an active component, an adjuvant, and a carrier;

[0075] The active component includes Fe3O4; the auxiliary agent includes CeO2; the carrier includes Al2O3;

[0076] The second component includes CaO, Al2O3 and Ca 12 Al 14 O33 .

[0077] The catalyst provided by the present invention contains dual sites of catalysis and adsorption, wherein the first component plays a catalytic role and the second component plays an adsorption role, which can simultaneously promote CO conversion and remove the generated CO2, break the contradiction between slow kinetics at low temperatures and thermodynamic equilibrium at high temperatures, further improve the conversion efficiency and realize in-situ decarbonization to prepare high-purity hydrogen.

[0078] The "ultra-high temperature" mentioned in the present invention refers to 550°C-700°C.

[0079] According to a specific embodiment of the present invention, the mass ratio of the active component, the auxiliary agent and the carrier in the first component satisfies (75-85):(5-15):10. As some specific examples, the mass ratio of the active component, the auxiliary agent and the carrier in the first component may be 75:5:10, 75:15:10, 85:5:10, 85:15:10, etc.

[0080] According to a specific embodiment of the present invention, the mass ratio of the first component to the catalyst is 20%-40%. As some specific examples, the mass ratio of the first component to the catalyst may be 20%, 25%, 30%, 35%, 40%, etc.

[0081] According to a specific embodiment of the present invention, the molar ratio of the elements Ca / Al in the second component is (90-60):(10-40). As some specific examples, the molar ratio of the elements Ca / Al in the second component may be 90:10, 80:20, 70:30, 60:40, etc.

[0082] According to a specific embodiment of the present invention, the particle size of the catalyst is 0.2 mm-1 mm, and the particle size of the catalyst is preferably in a form of different particle size gradations.

[0083] According to an embodiment of the present invention, the second aspect of the present invention provides a method for preparing the catalyst according to the first aspect, comprising the following steps:

[0084] (1) preparing a first mixed solution containing an iron salt, a cerium salt and a first aluminum salt, adjusting the pH value of the first mixed solution to 9-10, and obtaining a first component precursor through a precipitation reaction.

[0085] According to a specific embodiment of the present invention, the type of the iron salt is not particularly limited. As some specific examples, the iron salt includes iron nitrate.

[0086] According to a specific embodiment of the present invention, the type of the cerium salt is not particularly limited. As some specific examples, the cerium salt includes cerium nitrate.

[0087] According to a specific embodiment of the present invention, the type of the first aluminum salt is not particularly limited. As some specific examples, the first aluminum salt includes aluminum nitrate.

[0088] According to a specific embodiment of the present invention, the type of the regulator for adjusting the pH value of the first mixed solution is not particularly limited. As some specific examples, the regulator includes a NaOH solution.

[0089] According to a specific embodiment of the present invention, the concentration of the regulator is not particularly limited. As some specific examples, the concentration of the regulator may be 1 M, etc.

[0090] According to a specific embodiment of the present invention, the preparation method also includes: preparing a first mixed solution containing iron salt, cerium salt and a first aluminum salt, adjusting the pH value of the first mixed solution to 9-10, and obtaining a first component precursor through precipitation reaction, aging, filtration, washing, and secondary drying.

[0091] According to a specific embodiment of the present invention, the aging temperature is 60°C-90°C. As some specific examples, the aging temperature may be 60°C, 70°C, 80°C, 90°C, etc.

[0092] According to a specific embodiment of the present invention, the aging time is 1 hour to 3 hours. As some specific examples, the aging time may be 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, etc.

[0093] According to a specific embodiment of the present invention, the temperature of the secondary drying is 100° C.-120° C. As some specific examples, the temperature of the secondary drying may be 100° C., 110° C., 120° C., etc.

[0094] According to a specific embodiment of the present invention, the secondary drying time is 4 hours to 6 hours. As some specific examples, the secondary drying time may be 4 hours, 5 hours, 6 hours, etc.

[0095] (2) preparing a second mixed solution containing a calcium salt and a second aluminum salt, and drying the solution to obtain a second component precursor.

[0096] According to a specific embodiment of the present invention, the type of the calcium salt is not particularly limited. As some specific examples, the calcium salt includes calcium acetate.

[0097] According to a specific embodiment of the present invention, the type of the second aluminum salt is not particularly limited. As some specific examples, the second aluminum salt includes aluminum nitrate nonahydrate.

[0098] According to a specific embodiment of the present invention, the drying temperature is 100° C.-120° C. As some specific examples, the drying temperature may be 100° C., 110° C., 120° C., etc.

[0099] According to a specific embodiment of the present invention, the drying time is 4 hours to 6 hours. As some specific examples, the drying time may be 4 hours, 5 hours, 6 hours, etc.

[0100] (3) The first component precursor and the second component precursor are calcined and ground respectively to obtain the first component and the second component.

[0101] According to a specific embodiment of the present invention, the calcination temperature is independently 700°C-900°C. As some specific examples, the calcination temperature can be independently 700°C, 750°C, 800°C, 850°C, 900°C, etc.

[0102] According to a specific embodiment of the present invention, the calcination time is independently 4h-6h. As some specific examples, the calcination time can be independently 4h, 4.5h, 5.0h, 5.5h, 6h, etc.

[0103] According to a specific embodiment of the present invention, the heating rate of the calcination is not particularly limited. As some specific examples, the heating rate of the calcination may be 5° C. / min, etc.

[0104] (4) Mixing the first component and the second component to obtain the catalyst.

[0105] According to a specific embodiment of the present invention, this step may specifically include: physically mixing and grinding the first component and the second component in proportion to obtain catalyst powder.

[0106] According to an embodiment of the present invention, the third aspect of the present invention provides the use of the catalyst described in the first aspect or the catalyst obtained according to the preparation method described in the second aspect in an ultra-high temperature water gas shift reaction.

[0107] According to an embodiment of the present invention, a fourth aspect of the present invention provides a device for producing hydrogen from syngas water-gas shift, the structural schematic diagram of which is shown in FIG. Figure 1 , the device comprises a reaction unit 100 and a regeneration unit 200, the reaction unit 100 comprises a reaction device 110 and a separation device 120, and the regeneration unit 200 comprises a regeneration device 210;

[0108] The reaction device 110 includes a first reaction zone 111 and a second reaction zone 112 that are connected to each other, wherein the second reaction zone 112 is located above the first reaction zone 111, and the diameter of the first reaction zone 111 is greater than or equal to the diameter of the second reaction zone 112. The reaction device 110 is used for hydrogen production by water-gas shift of synthesis gas and CO2 removal;

[0109] A gas inlet is provided at the bottom of the first reaction zone 111 for providing a mixed gas to the reaction device 110, wherein the mixed gas includes synthesis gas and water vapor;

[0110] The bottom side wall of the second reaction zone 112 is provided with a feed port for providing the catalyst described in the first aspect or the catalyst obtained according to the preparation method described in the second aspect to the reaction device 110;

[0111] The separation device 120 is connected to the top of the second reaction zone 112 in the reaction device 110, and is used to separate the product gas and the used catalyst, wherein the product gas includes hydrogen and impurities;

[0112] The regeneration device 210 is connected to the separation device 120 and the reaction device 110 respectively, and is used to recover the used catalyst and regenerate the catalyst.

[0113] The reaction device 110 provided by the present invention includes a first reaction zone 111 with a wider bottom and a second reaction zone 112 with a narrower top, which increases the contact time between the catalyst and the reaction gas and realizes a full reaction. The reaction occurring in the reaction device 110 can be expressed as CO+H2O+CaO=H2+CaCO3, and the two reaction zones form a similar two-stage transformation, which can realize further fine transformation and fully utilize the reaction heat through heat exchange and temperature control.

[0114] According to a specific embodiment of the present invention, a feeder may be provided at the feed port, and the type of the feeder is not particularly limited. As some specific examples, the feeder includes a screw feeder.

[0115] According to a specific embodiment of the present invention, the type of the separation device 120 is not particularly limited. As some specific examples, the separation device 120 includes a cyclone, and the cyclone also has a partial dust removal function.

[0116] According to a specific embodiment of the present invention, the regeneration unit 200 further includes a connected heat exchange device 220 and a CO2 storage device 230 , wherein the heat exchange device 220 is connected to the top of the regeneration device 210 , and the CO2 storage device 230 is connected to the bottom of the regeneration device 210 .

[0117] According to a specific embodiment of the present invention, the type of the CO2 storage device 230 is not particularly limited. As some specific examples, the CO2 storage device 230 includes a CO2 storage tank.

[0118] According to a specific embodiment of the present invention, the device further comprises a purification unit 300, which is connected to the separation device 120 and is used to collect the product gas and improve the purity of hydrogen in the product gas.

[0119] According to a specific embodiment of the present invention, the purification unit 300 includes a quenching device 310, an acid removal device 320, a gas-liquid separation device 330, a filtering device 340 and an H2 storage device 350 which are connected in sequence.

[0120] According to a specific embodiment of the present invention, the type of the quenching device 310 is not particularly limited. As some specific examples, the quenching device 310 includes a condenser, and the quenching device 310 is used to reduce the product gas temperature to below 200°C.

[0121] According to a specific embodiment of the present invention, the type of the acid removal device 320 is not particularly limited. As some specific examples, the acid removal device 320 includes a deacidification tower, and the acid removal device 320 is used to deacidify a small amount of CO2, HCl, HCN, and H2S impurities in the product gas.

[0122] According to a specific embodiment of the present invention, the gas-liquid separation device 330 is used to separate the liquid in the product gas and promotes dust removal.

[0123] According to a specific embodiment of the present invention, the type of the filtering device 340 is not particularly limited. As some specific examples, the filtering device 340 includes a fine filter, and the filtering device 340 is used to remove remaining harmful substances and odors.

[0124] According to a specific embodiment of the present invention, the type of the H2 storage device 350 is not particularly limited. As some specific examples, the H2 storage device 350 includes an H2 storage tank.

[0125] According to an embodiment of the present invention, a fifth aspect of the present invention provides a process for producing hydrogen by water-gas shift of synthesis gas, see Figure 1-2 The process adopts the equipment described in the fourth aspect and comprises the following steps:

[0126] (1) The catalyst is transported into the reaction device 110 through the feed port.

[0127] The catalyst entering the reaction device 110 enters the first reaction zone 111 from top to bottom due to gravity.

[0128] According to a specific embodiment of the present invention, the delivery rate of the catalyst is not particularly limited and may be 10kg / h-20kg / h. As some specific examples, the delivery rate of the catalyst may be 10kg / h, 15kg / h, 20kg / h, etc.

[0129] (2) The mixed gas enters the reaction device 110 through the gas inlet, flows upward through the first reaction zone 111 and the second reaction zone 112 in sequence, undergoes a shift reaction under the action of the catalyst, and obtains a shifted gas.

[0130] When the mixed gas is passed into the reaction device 110 and flows into the first reaction zone 111, part of the catalyst is purged and gradually brought into the second reaction zone 112. In the presence of the catalyst, the synthesis gas and water vapor undergo conversion reaction in the first reaction zone 111 and the second reaction zone 112 to generate CO2 and hydrogen. At the same time, a carbonation reaction occurs at the adsorption site to generate CaCO3. This reaction can remove a large amount of CO2. The converted gas after the reaction takes away the heat released by the conversion reaction and part of the bifunctional catalyst and enters the separation device 120.

[0131] According to a specific embodiment of the present invention, the reaction temperatures of the first reaction zone 111 and the second reaction zone 112 are the same, both of which are 550°C-650°C. As some specific examples, the reaction temperatures of the first reaction zone 111 and the second reaction zone 112 may be 550°C, 600°C, 650°C, etc.

[0132] According to a specific embodiment of the present invention, the pressure of the conversion reaction is 0.1Mpa-0.6Mpa. As some specific examples, the pressure of the conversion reaction may be 0.1Mpa, 0.2Mpa, 0.3Mpa, 0.4Mpa, 0.5Mpa, 0.6Mpa, etc.

[0133] According to a specific embodiment of the present invention, the synthesis gas includes 30%-40% CO, 25%-35% CO2, ≤5% CH4 and 15%-25% H2 by volume. As some specific examples, the synthesis gas includes 40% CO, 30% CO2, 5% CH4 and 25% H2 by volume; 40% CO, 35% CO2, 20% H2, 5% CH4; 35% CO, 35% CO2, 5% CH4 and 25% H2, etc.

[0134] According to a specific embodiment of the present invention, the volume ratio of water vapor in the mixed gas to CO in the synthesis gas is (1-3):1. As some specific examples, the volume ratio of water vapor in the mixed gas to CO in the synthesis gas may be 1:1, 1.5:1, 2:1, 2.5:1, 3:1, etc.

[0135] According to a specific embodiment of the present invention, the tar content in the synthesis gas is less than 1g / Nm 3 , the temperature is 450℃-650℃. As some specific examples, the temperature may be 450℃, 500℃, 550℃, 600℃, 650℃, etc. The source of the synthesis gas is not particularly limited, and may be the synthesis gas produced by the low-tar gasification process of organic solid waste.

[0136] According to a specific embodiment of the present invention, the temperature of the mixed gas is not less than 450° C. As some specific examples, the temperature of the mixed gas may be 450° C., 500° C., 550° C., etc.

[0137] According to a specific embodiment of the present invention, the temperature of the air inlet is 500°C-650°C. As some specific examples, the temperature of the air inlet may be 500°C, 550°C, 600°C, 650°C, etc.

[0138] According to a specific embodiment of the present invention, the method for preparing the water vapor is not particularly limited. As some specific examples, the water vapor can be prepared by a steam generator.

[0139] According to a specific embodiment of the present invention, the process also includes: preheating and mixing the synthesis gas and the water vapor in a gas mixing chamber, and the obtained mixed gas enters the reaction device 110 through the air inlet, flows upward through the first reaction zone 111 and the second reaction zone 112 in sequence, and a conversion reaction occurs under the action of the catalyst to obtain a conversion gas.

[0140] (3) The conversion gas enters the separation device 120 to separate the product gas and the used catalyst in the conversion gas. The product gas is discharged from the top of the separation device 120, and the used catalyst enters the regeneration device 210 from the bottom of the separation device 120.

[0141] After the conversion gas enters the separation device 120, the used catalyst enters the regeneration device 210 from the bottom of the separation device 120 under the action of gravity, and the product gas after gas-solid separation is discharged from the top of the separation device 120 and can subsequently enter the purification unit 300.

[0142] (4) CO2 is introduced into the regeneration device 210 from bottom to top, and the used catalyst is decomposed to obtain regenerated catalyst and CO2, wherein CO2 is discharged from the top of the regeneration device 210, and the regenerated catalyst enters the reaction device 110 from the bottom of the regeneration device 210 for recycling.

[0143] CO2 is introduced from the bottom of the regeneration device 210 and flows from bottom to top through the entire regeneration device 210. The used catalyst enters from the top of the regeneration device 210 and flows from top to bottom through the entire regeneration device 210. Under the action of high temperature and CO2, the used catalyst removes CO2 and carbon deposits and is regenerated. The generated CO2 is discharged from the top of the regeneration device 210, condensed by the heat exchange device 220, and then enters the CO2 storage device 230. The regenerated catalyst is sent from the bottom of the regeneration device 210 to the bottom of the reaction device 110 for recycling.

[0144] According to a specific embodiment of the present invention, the decomposition temperature of the used catalyst is 800°C-900°C. As some specific examples, the decomposition temperature of the used catalyst may be 800°C, 820°C, 840°C, 860°C, 880°C, 900°C, etc.

[0145] According to a specific embodiment of the present invention, the process further includes: passing the product gas discharged from the top of the separation device 120 into the purification unit 300, and obtaining hydrogen after cooling, deacidification, gas-liquid separation, and filtration. The operation can be specifically as follows: the product gas discharged from the top of the separation device 120 first enters the quenching device 310 to reduce the temperature of the high-temperature product gas to below 200°C, and then enters the deacidification device 320 to deacidify the product gas through alkaline slurry to effectively remove the acidic substances and smoke in the product gas, and then enters the gas-liquid separation device 330 to separate the liquid in the product gas through centrifugal force, which has a promoting effect on dust removal, and finally enters the filtering device 340 to remove the remaining harmful substances and odors through activated carbon to obtain pure hydrogen, the purity of which can reach 96.0%.

[0146] The process is simple to operate and realizes the recycling of catalysts, while matching the synthesis gas temperature at the gasification outlet, greatly saving costs and improving production efficiency. As the organic solid waste gasification process develops towards pressurization and low tar, the ultra-high temperature conversion process has broad development prospects.

[0147] The scheme of the present invention will be explained below in conjunction with the embodiments. It will be appreciated by those skilled in the art that the following embodiments are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. Where specific techniques or conditions are not indicated in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used are not indicated by the manufacturer and are all conventional products that can be obtained commercially.

[0148] Example 1

[0149] This embodiment uses gasification synthesis gas (composed of 40% CO, 35% CO2, 20% H2, 5% CH4) as raw material, and uses a catalyst in which the first component accounts for 40wt% of the catalyst, and the mass ratio of Fe3O4, CeO2 and Al2O3 in the first component satisfies 75:15:10; the molar ratio of the element Ca / Al in the second component is 90:10.

[0150] (1) adding the ground and mixed catalyst into the hopper, opening the feeder, and conveying the catalyst in the hopper into the reactor at a rate of 10 kg / h. The catalyst conveyed into the reactor enters the first reaction zone from top to bottom due to gravity;

[0151] (2) The high-temperature synthesis gas obtained by gasification is preheated and mixed with water vapor in a mixing chamber at a volume ratio of 5:4, and then flows upward into the first reaction zone of the reactor at a gas flow rate of 1 m / s. At this time, part of the catalyst is purged and gradually brought into the second reaction zone. The synthesis gas and water vapor undergo a shift reaction in the first and second reaction zones in the presence of the catalyst to generate CO2 and hydrogen. At the same time, a carbonation reaction occurs at the adsorption site to remove a large amount of CO2. The shift gas after the reaction takes away the heat released by the shift reaction and part of the catalyst and enters the cyclone inlet;

[0152] (3) The converted gas flows through the cyclone, and the catalyst carried by it enters the top inlet of the regenerator from the bottom of the cyclone under the action of gravity, while the product gas after gas-solid separation is discharged from the top of the cyclone into the purification unit. At the same time, the cyclone also has a partial dust removal effect;

[0153] (4) CO2 is introduced from the bottom of the regenerator and flows through the entire regenerator from bottom to top. The used catalyst enters from the top of the regenerator and flows through the entire regenerator from top to bottom. Under the action of high temperature of 850°C and CO2, the used catalyst removes CO2 and carbon deposits and is regenerated. The generated CO2 is discharged from the top of the regenerator, condensed in the heat exchanger, and then enters the CO2 storage tank. The regenerated catalyst is sent from the bottom of the regenerator to the bottom of the reactor for recycling.

[0154] (5) The product gas discharged from the top of the cyclone first enters the condenser to reduce the temperature of the high-temperature product gas to below 200°C, and then enters the deacidification tower of the wet deacidification equipment to deacidify the product gas with alkaline slurry, effectively removing the acidic substances and smoke in the product gas. Then it enters the gas-liquid separator to separate the liquid in the product gas by centrifugal force, which also promotes dust removal. Finally, it enters the fine filter to remove the remaining harmful substances and odors with activated carbon to obtain hydrogen.

[0155] The purity of the hydrogen obtained in Example 1 was 96.0%, and the conversion rate of CO in the shift reaction was 90.0%.

[0156] Example 2

[0157] The only difference between this embodiment and embodiment 1 is that the proportion of the first component in the catalyst is 20 wt %.

[0158] The hydrogen purity obtained in this embodiment is 95.2%, and the conversion rate of CO in the shift reaction is 88.0%.

[0159] Example 3

[0160] The only difference between this embodiment and embodiment 1 is that the mass ratio of Fe3O4, CeO2 and Al2O3 in the first component is 80:10:10.

[0161] The hydrogen purity obtained in this embodiment is 95.44%, and the conversion rate of CO in the shift reaction is 88.6%.

[0162] Comparative Example 1

[0163] The difference between this comparative example and Example 1 is that the catalyst used is composed of iron, manganese and copper oxides in a mass ratio of 70:20:10, and the conversion reaction is carried out at medium and low temperature (200-450°C).

[0164] The comparative example obtained a hydrogen purity of 60% and a CO conversion rate of 95.0% in the shift reaction.

[0165] The catalyst used in this comparative example has no adsorption active sites, so the purity of the hydrogen produced is low, and the catalyst is only suitable for medium and low temperature (200°C-450°C) conversion reactions, but not for ultra-high temperature (550°C-700°C) conversion reactions in the present invention.

[0166] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0167] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A catalyst for ultra-high temperature water gas shift reaction, characterized in that: The catalyst comprises a first component and a second component; The first component includes an active component, an adjuvant, and a carrier; The active component includes Fe3O4; the auxiliary agent includes CeO2; the carrier includes Al2O3; The second component includes CaO, Al2O3 and Ca 12 Al 14 O 33 .

2. The catalyst according to claim 1, characterized in that The mass ratio of the active component, the auxiliary agent and the carrier in the first component satisfies (75-85):(5-15):10; Optionally, the mass ratio of the first component to the catalyst is 20%-40%; Optionally, the molar ratio of the elements Ca / Al in the second component is (90-60):(10-40); Optionally, the catalyst has a particle size of 0.2 mm to 1 mm.

3. A method for preparing the catalyst according to claim 1 or 2, characterized in that: The following steps are involved: Preparing a first mixed solution containing an iron salt, a cerium salt and a first aluminum salt, adjusting the pH value of the first mixed solution to 9-10, and obtaining a first component precursor through a precipitation reaction; preparing a second mixed solution containing a calcium salt and a second aluminum salt, and drying the solution to obtain a second component precursor; The first component precursor and the second component precursor are calcined and ground respectively to obtain the first component and the second component; The first component and the second component are mixed to obtain the catalyst.

4. The preparation method according to claim 3, characterized in that: The iron salt includes iron nitrate; Optionally, the cerium salt comprises cerium nitrate; Optionally, the first aluminum salt comprises aluminum nitrate; Optionally, the calcium salt comprises calcium acetate; Optionally, the second aluminum salt comprises aluminum nitrate nonahydrate.

5. The preparation method according to claim 3, characterized in that: The drying temperature is 100°C-120°C; Optionally, the drying time is 4h-6h; Optionally, the calcination temperature is independently 700°C-900°C; Optionally, the calcination time is independently 4h-6h.

6. Use of the catalyst according to claim 1 or 2 or the catalyst obtained according to the preparation method according to any one of claims 3 to 5 in an ultra-high temperature water gas shift reaction.

7. A device for producing hydrogen by water-gas shift of synthesis gas, characterized in that: The device comprises a reaction unit and a regeneration unit, wherein the reaction unit comprises a reaction device and a separation device, and the regeneration unit comprises a regeneration device; The reaction device comprises a first reaction zone and a second reaction zone connected to each other, the second reaction zone is located above the first reaction zone, the diameter of the first reaction zone is greater than or equal to the diameter of the second reaction zone, and the reaction device is used for hydrogen production and CO2 removal by water-gas shift of synthesis gas; A gas inlet is provided at the bottom of the first reaction zone for providing a mixed gas to the reaction device, wherein the mixed gas includes synthesis gas and water vapor; The bottom side wall of the second reaction zone is provided with a feed port for providing the catalyst according to claim 1 or 2 or the catalyst obtained by the preparation method according to any one of claims 3 to 5 to the reaction device; The separation device is connected to the top of the second reaction zone in the reaction device and is used to separate the product gas and the used catalyst, wherein the product gas includes hydrogen and impurities; The regeneration device is connected to the separation device and the reaction device respectively, and is used for recovering the used catalyst and regenerating the catalyst.

8. The device according to claim 7, characterized in that The regeneration unit also includes a connected heat exchange device and a CO2 storage device, wherein the heat exchange device is connected to the top of the regeneration device, and the CO2 storage device is connected to the bottom of the regeneration device; Optionally, the device further comprises a purification unit, which is connected to the separation device and is used to collect the product gas and improve the purity of hydrogen in the product gas; Optionally, the purification unit comprises a quenching device, an acid removal device, a gas-liquid separation device, a filtering device and a H2 storage device which are connected in sequence.

9. A process for producing hydrogen by water-gas shift of synthesis gas, characterized in that: The process uses the equipment described in any one of claims 7-8, comprising the following steps: delivering the catalyst into the reaction device through the feed port; The mixed gas enters the reaction device through the gas inlet, flows upward through the first reaction zone and the second reaction zone in sequence, undergoes a shift reaction under the action of the catalyst, and obtains a shifted gas; The shifted gas enters the separation device to separate the product gas and the used catalyst in the shifted gas, the product gas is discharged from the top of the separation device, and the used catalyst enters the regeneration device from the bottom of the separation device; CO2 is introduced into the regeneration device from bottom to top, and the used catalyst is decomposed to obtain regenerated catalyst and CO2, wherein CO2 is discharged from the top of the regeneration device, and the regenerated catalyst enters the reaction device from the bottom of the regeneration device for recycling.

10. The process according to claim 9, characterized in that The reaction temperatures of the first reaction zone and the second reaction zone are the same, both of which are 550°C-650°C; Optionally, the pressure of the shift reaction is 0.1Mpa-0.6Mpa; Optionally, the synthesis gas comprises 30%-40% CO, 25%-35% CO2, ≤5% CH4 and 15%-25% H2 by volume; Optionally, the volume ratio of water vapor in the mixed gas to CO in the synthesis gas is (1-3):1; Optionally, the tar content in the synthesis gas is less than 1g / Nm 3 , the temperature is 450℃-650℃; Optionally, the temperature of the mixed gas is not less than 450°C; Optionally, the temperature of the air inlet is 500°C-650°C; Optionally, the decomposition temperature of the used catalyst is 800°C-900°C; Optionally, the process further comprises: passing the product gas discharged from the top of the separation device into the purification unit, and obtaining hydrogen through cooling, deacidification, gas-liquid separation, and filtration.

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