A methanol steam reforming catalyst and its preparation method and application

Abstract

The present invention provides a method for preparing a methanol steam reforming catalyst, which belongs to the technical field of catalyst preparation. The main steps are as follows: a mixed salt solution containing a soluble copper salt, a soluble zinc salt, and a soluble aluminum salt and a precipitant aqueous solution are co-precipitated in parallel to obtain a co-precipitate; the co-precipitate is washed to obtain a first filter cake; under ultrasonic vibration conditions, the first filter cake and a high-boiling point organic aqueous solution are stirred and slurried, and filtered to obtain a second filter cake; the second filter cake is dried, calcined in anoxic conditions, graphite and deionized water are added, and sheeting is performed to obtain the methanol steam reforming catalyst. The catalyst preparation process of the present invention is simple, no nitrogen oxides are generated during the process, it is safe and environmentally friendly, and has good industrial prospects; the catalyst prepared by the present invention has the characteristics of high activity and excellent resistance to abnormal operating condition fluctuations, and the catalyst has good sintering resistance and stability.

Description

Technical Field

[0001] The present invention belongs to the technical field of catalysis, and in particular relates to a methanol steam reforming catalyst and a preparation method and application thereof. Background Art

[0002] The development and utilization of hydrogen energy is an effective means to achieve "carbon peak" and "carbon neutrality". There are a variety of hydrogen production processes in the traditional hydrogen production field, among which the methanol steam reforming hydrogen production process is mainly used for small-scale hydrogen production and has a wide range of applicable scenarios. Currently, the commonly used methanol steam reforming catalysts are mainly Cu-based catalysts, which have the advantages of high activity and low reaction temperature. In industry, methanol steam reforming catalysts are mainly Cu / Zn / Al2O3 series catalysts prepared by co-precipitation method, which have good low-temperature activity, high hydrogen selectivity and low price. However, Cu-based catalysts also have disadvantages such as easy poisoning, low stability and easy sintering at high temperature.

[0003] To improve catalyst stability, those skilled in the art have employed various methods, such as adding rare earth elements and alkaline earth elements. However, in practice, it has been found that while these elements can improve catalyst stability, they can also lead to a sharp decrease in catalytic activity. Others have added carbon components to catalysts to improve performance, but these existing methods readily generate nitrogen oxides during calcination, which is environmentally unfriendly.

[0004] CN114950443A discloses a copper-based catalyst for methanol steam reforming to produce hydrogen and its preparation method. The catalyst precursor is prepared using copper, zinc, and aluminum salts as raw materials, with sugars added as organic chelating agents. A pre-carbonization process stabilizes the metal and inhibits sintering of the copper species during calcination. This method does not produce wastewater, but the calcination process does produce nitrogen oxides, which is environmentally unfriendly.

[0005] CN108654591A discloses a supported catalyst, preparation method, application and Fischer-Tropsch synthesis method. The main steps of the method are to load a first metal component on a carrier, continue to impregnate a high-boiling point organic matter after roasting and decomposition, realize the loading of a carbon component after roasting and carbonization, and then continue to load a second active metal component. The first metal component of the catalyst and the carbon component formed by heat treatment are conducive to promoting the directional loading of the second metal component. The catalyst preparation process undergoes multiple impregnations and roastings, and the steps are cumbersome. In addition, there is also the problem of generating nitrogen oxides during the roasting process. Summary of the Invention

[0006] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a method for preparing a methanol steam reforming catalyst, which has a simple preparation process, does not produce nitrogen oxides during the process, is safe and environmentally friendly, and has good industrial prospects; the present invention also provides a methanol steam reforming catalyst, which has the characteristics of high activity and excellent resistance to abnormal operating condition fluctuations. At the same time, the catalyst has good sintering resistance and good stability.

[0007] In order to achieve the above object, according to one aspect of the present invention, a method for preparing a methanol steam reforming catalyst is provided, comprising the following steps:

[0008] (1) A mixed salt solution containing soluble copper salt, soluble zinc salt, and soluble aluminum salt and a precipitant aqueous solution are co-precipitated in parallel, and the solution is aged after its color changes from light blue to blue-green to obtain a co-precipitate;

[0009] (2) Wash the coprecipitate until it is free of Na + Detection to obtain a first filter cake, wherein the mass moisture content of the first filter cake is 150%-200%;

[0010] (3) Under ultrasonic vibration conditions, the first filter cake and the high-boiling point organic aqueous solution are stirred and slurried, and filtered to obtain a second filter cake, wherein the mass moisture content of the second filter cake is 140%-150%;

[0011] (4) Drying the second filter cake, calcining it in an oxygen-free state, adding graphite and deionized water, and forming it into tablets to obtain the methanol steam reforming catalyst.

[0012] In some embodiments, in step (1), the soluble copper salt includes one or more of copper nitrate, copper oxalate, and copper acetate.

[0013] In some embodiments, in step (1), the soluble zinc salt includes one or more of zinc nitrate, zinc oxalate, and zinc acetate.

[0014] In some embodiments, in step (1), the soluble aluminum salt is aluminum nitrate.

[0015] In some embodiments, in step (1), the precipitant includes one or more of sodium hydroxide, sodium carbonate, and sodium bicarbonate.

[0016] In some embodiments, in step (1), the concentration of the mixed saline solution is 0.5 mol / L-1.5 mol / L.

[0017] In some embodiments, in step (1), the concentration of the precipitant aqueous solution is 0.5 mol / L-1.5 mol / L.

[0018] In some embodiments, in step (1), the coprecipitation reaction conditions are: under stirring, the reaction temperature is controlled at 60°C-70°C, and the pH is 7.5-7.8.

[0019] In some embodiments, in step (1), the aging conditions are: aging temperature is 60°C-70°C, and aging time is 1.5h-8h.

[0020] In some embodiments, in step (2), the washing is performed by suction filtration or filter pressing using deionized water, and the temperature of the deionized water is 80°C-85°C.

[0021] In some embodiments, in step (3), the high-boiling-point organic matter includes one or more of carbohydrates and polyhydroxy organic matter.

[0022] In some embodiments, in step (3), the concentration of the high-boiling-point organic aqueous solution is 40 g / L-115 g / L.

[0023] Furthermore, the carbohydrates include one or more of glucose, sucrose, lactose, and soluble starch.

[0024] Furthermore, the polyhydroxy organic compound includes one or more of ethylene glycol, glycerol, and polyethylene glycol.

[0025] In some embodiments, in step (4), the drying temperature is 100°C-150°C, and the drying time is 8h-24h.

[0026] In some embodiments, in step (4), the anaerobic calcination temperature is 350°C-450°C, and the anaerobic calcination time is 2h-8h.

[0027] According to another aspect of the present invention, there is also provided a methanol steam reforming catalyst prepared by the above preparation method, which comprises the following components in percentage by weight based on the total amount:

[0028] CuO40%-65%;

[0029] ZnO23%-50%;

[0030] Al2O35%-25%;

[0031] 3%-6% of the carbon component is generated by the decomposition of high-boiling point organic matter; and the balance is graphite.

[0032] According to another aspect of the present invention, the present invention also provides a catalyst prepared by the above preparation method or the use of the above catalyst in a methanol steam reforming hydrogen production process.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) When the catalyst is frequently started and stopped under abnormal operating conditions, the active metal grains will grow during the repeated oxidation and reduction process of the catalyst, and the activity will decrease significantly. The preparation method of the present invention can further control the content of the carbon component generated by the high-boiling-point organic matter in the catalyst by controlling the content of the high-boiling-point organic matter, so that the carbon component can effectively separate the active metal grains and avoid excessive carbon components covering the active metal surface; at the same time, because it contains a carbon component that is evenly dispersed and stable in nature, a "carbon fence" is formed, so that the active metal grains in the catalyst are evenly spaced and cannot be quickly agglomerated and grown during use. Therefore, after the operating conditions of the catalyst of the present invention fluctuate, the growth rate of the metal grains is limited because the active metal grains are evenly spaced by the carbon component. With the normal use of the catalyst, the oxidized metal grains are slowly reduced and the grains do not grow. The damaged catalyst activity can be repaired to a certain extent, thereby improving the catalyst's resistance to abnormal operating conditions fluctuations and its service life.

[0035] (2) The catalyst of the present invention contains a specific amount of carbon components generated from high-boiling-point organic matter. The carbon components are evenly dispersed in the catalyst and have stable properties, so that the active metal grains in the catalyst are evenly spaced and cannot agglomerate and grow rapidly during use. Therefore, the catalyst has the characteristics of high activity, good sintering resistance and good stability.

[0036] (3) The preparation method of the methanol steam reforming catalyst of the present invention is simple to operate, has wide adaptability, requires little process change, is low in cost, does not generate nitrogen oxides during the preparation process, and is environmentally friendly and pollution-free. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0038] Figure 1 (a) and (b) are SEM images of the catalyst cat-1 prepared in Example 1 of the present invention before and after the catalytic reaction, respectively.

[0039] Figure 2 (a) and (b) are SEM images of the catalyst D-cat-1 prepared in Comparative Example 1 of the present invention before and after the catalytic reaction, respectively.

[0040] Figure 3 (a) and (b) are SEM images of the catalyst D-cat-2 prepared in Comparative Example 2 of the present invention before and after the catalytic reaction, respectively.

[0041] Figure 4 (a) and (b) are SEM images of the catalyst D-cat-3 prepared in Comparative Example 3 of the present invention before and after the catalytic reaction, respectively.

[0042] Figure 5 (a) and (b) are SEM images of the catalyst D-cat-4 prepared in Comparative Example 4 of the present invention before and after the catalytic reaction, respectively.

[0043] Figure 6 (a) and (b) are SEM images of the catalyst D-cat-5 prepared in Comparative Example 5 of the present invention before and after the catalytic reaction, respectively.

[0044] Figure 7 (a) and (b) are SEM images of the catalyst D-cat-6 prepared in Comparative Example 6 of the present invention before and after the catalytic reaction, respectively.

[0045] Figure 8 This is a catalytic activity distribution diagram of the catalyst prepared in Example 1 of the present invention under abnormal operating condition fluctuation simulation. DETAILED DESCRIPTION

[0046] To facilitate understanding of the features and effects of the present invention by those skilled in the art, the following provides a general description and definition of the terms and expressions used in the specification and claims. Unless otherwise indicated, all technical and scientific terms used herein have the ordinary meanings as understood by those skilled in the art regarding the present invention. In the event of conflict, the definitions in this specification shall prevail.

[0047] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0048] Herein, when describing embodiments or examples, it should be understood that they are not intended to limit the present invention to these embodiments or examples. On the contrary, all alternatives, modifications and equivalents of the methods and materials described herein are encompassed within the scope defined by the claims.

[0049] In this document, for the sake of brevity, not all possible combinations of the various technical features in each embodiment or example are described. Therefore, as long as there are no contradictions in the combination of these technical features, the various technical features in each embodiment or example can be combined in any way, and all possible combinations should be considered to be within the scope of this specification.

[0050] The present invention provides a method for preparing a methanol steam reforming catalyst, comprising the following steps:

[0051] (1) A mixed salt solution containing soluble copper salt, soluble zinc salt, and soluble aluminum salt and a precipitant aqueous solution are co-precipitated in parallel, and the solution is aged after its color changes from light blue to blue-green to obtain a co-precipitate;

[0052] (2) Wash the coprecipitate until it is free of Na + Detection to obtain a first filter cake, wherein the mass moisture content of the first filter cake is 150%-200%;

[0053] (3) Under ultrasonic vibration conditions, the first filter cake and the high-boiling point organic aqueous solution are stirred and slurried, and filtered to obtain a second filter cake, wherein the mass moisture content of the second filter cake is 140%-150%;

[0054] (4) Drying the second filter cake, calcining it in an oxygen-free state, adding graphite and deionized water, and forming it into tablets to obtain the methanol steam reforming catalyst.

[0055] According to the preparation method provided by the present invention, in some embodiments, in step (1), the soluble copper salt includes one or more of copper nitrate, copper oxalate, and copper acetate. Preferably, the soluble copper salt is copper nitrate.

[0056] According to the preparation method provided by the present invention, in some embodiments, in step (1), the soluble zinc salt includes one or more of zinc nitrate, zinc oxalate, and zinc acetate. Preferably, the soluble zinc salt is zinc nitrate.

[0057] According to the preparation method provided by the present invention, in some embodiments, in step (1), the soluble aluminum salt is aluminum nitrate.

[0058] According to the preparation method provided by the present invention, in some embodiments, in step (1), the precipitant includes one or more of sodium hydroxide, sodium carbonate, and sodium bicarbonate. Preferably, the precipitant is sodium carbonate.

[0059] According to the preparation method provided by the present invention, in some embodiments, in step (1), the concentration of the mixed saline solution is 0.5 mol / L-1.5 mol / L. It can be understood that its concentration can be any specific value among 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, 1.0 mol / L, 1.1 mol / L, 1.2 mol / L, 1.3 mol / L, 1.4 mol / L, 1.5 mol / L or any value within the range of 0.5 mol / L-1.5 mol / L.

[0060] According to the preparation method provided by the present invention, in some embodiments, in step (1), the molar ratio of copper ions to zinc ions in the mixed salt solution is (0.5-5):1, preferably (1-3):1; and the ratio of the total molar number of copper ions and zinc ions to the molar number of aluminum ions is (0.2-8):1, preferably (1-7):1, and more preferably (1-5):1. Under these ratios, the CuO in the catalyst can be fully refined and highly dispersed, forming a eutectic with ZnO and Al2O3, thereby improving the activity and heat resistance of the catalyst.

[0061] According to the preparation method provided by the present invention, in some embodiments, in step (1), the concentration of the precipitant aqueous solution is 0.5 mol / L-1.5 mol / L. It can be understood that its concentration can be any specific value among 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, 1.0 mol / L, 1.1 mol / L, 1.2 mol / L, 1.3 mol / L, 1.4 mol / L, 1.5 mol / L or any value within the range of 0.5 mol / L-1.5 mol / L.

[0062] According to the preparation method provided by the present invention, in some embodiments, in step (1), the mixed brine solution is preferably heated to 60°C-70°C and then co-precipitated with the precipitant aqueous solution. It can be understood that the temperature of the mixed brine solution can be any specific value of 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C, 70°C or any value within the range of 60°C-70°C.

[0063] According to the preparation method provided by the present invention, in some embodiments, in step (1), the precipitant aqueous solution is preferably heated to 60°C-70°C and then co-precipitated with the mixed brine solution. It can be understood that the temperature of the precipitant aqueous solution can be any specific value of 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C, 70°C or any value within the range of 60°C-70°C.

[0064] According to the preparation method provided by the present invention, in some embodiments, in step (1), the coprecipitation reaction conditions are: under stirring, the reaction temperature is controlled to be 60°C-70°C, and the pH is 7.5-7.8; it can be understood that the reaction temperature can be any specific value of 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C, 70°C, or any value within the range of 60°C-70°C; the pH can be any specific value of 7.5, 7.6, 7.7, 7.8, or any value within the range of 7.5-7.8.

[0065] According to the preparation method provided by the present invention, in some embodiments, in step (1), the aging temperature is 60°C-70°C. It can be understood that the aging temperature can be any specific value among 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C, and 70°C, or any value within the range of 60°C-70°C; the aging time is 1.5h-8h. It can be understood that the aging time can be any specific value among 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h, 5h, 5.5h, 6h, 6.5h, 7h, 7.5h, and 8h, or any value within the range of 1.5h-8h.

[0066] Coprecipitation refers to a process in which a precipitant is added to a solution containing two or more cations, which are present in a homogeneous phase. After precipitation, a uniform precipitate of the various components can be obtained. In the present invention, parallel coprecipitation refers to a method in which a precipitant solution and a solution containing metal cations are simultaneously added to a reactor in a proportional manner.

[0067] According to the preparation method provided by the present invention, in some embodiments, in step (2), the washing is performed by suction filtration or pressure filtration using deionized water, and the temperature of the deionized water is 80°C-85°C. It can be understood that the temperature of the deionized water can be any specific value of 80°C, 81°C, 82°C, 83°C, 84°C, 85°C or any value within the range of 80°C-85°C.

[0068] According to the preparation method provided by the present invention, in some embodiments, in step (2), the mass moisture content of the first filter cake is controlled to be 150%-200%. It is understood that the mass moisture content of the first filter cake can be any specific value among 150%, 155%, 160%, 165%, 170%, 175%, 180%, 185%, 190%, 195%, 200%, or any value within the range of 150%-200%. If the mass moisture content of the first filter cake is too low, the filter cake will be dry and hard, and a large number of spheres of different sizes will be formed during the beating process with the high-boiling point organic aqueous solution, resulting in an uneven slurry. The low moisture content will also cause the filtration to take longer. If the moisture content of the first filter cake is too high, the filter cake will be soft and not conducive to transfer, and it will also be difficult to control the concentration of the high-boiling point organic aqueous solution.

[0069] In the present invention, the high-boiling-point organic matter is an organic matter having a boiling point higher than 150° C. under normal pressure.

[0070] According to the preparation method provided by the present invention, in some embodiments, in step (3), the high-boiling-point organic matter includes one or more of carbohydrates and polyhydroxy organic matter.

[0071] Furthermore, the carbohydrates include one or more of glucose, sucrose, lactose, and soluble starch.

[0072] Furthermore, the polyhydroxy organic compound includes one or more of ethylene glycol, glycerol, and polyethylene glycol.

[0073] Furthermore, the high boiling point organic matter is polyethylene glycol with an average molecular weight of 4000.

[0074] According to the preparation method provided by the present invention, in some embodiments, the concentration of the high boiling point organic aqueous solution is 40g / L-115g / L. The specific concentration of the high boiling point organic aqueous solution can be calculated separately according to its carbon content. For example, the concentration of the polyethylene glycol aqueous solution is 40g / L-80g / L. It can be understood that the concentration of the polyethylene glycol aqueous solution can be any specific value of 40g / L, 45g / L, 50g / L, 55g / L, 60g / L, 65g / L, 70g / L, 75g / L, 80g / L or a range of 40g / L-80g / L. any value within the range of 55 g / L-115 g / L; the concentration of the aqueous solution of glucose, sucrose, lactose, soluble starch, ethylene glycol and glycerol is 55 g / L-115 g / L. It can be understood that the concentration of the aqueous solution of glucose, sucrose, lactose, soluble starch, ethylene glycol and glycerol can be any specific value of 55 g / L, 60 g / L, 65 g / L, 70 g / L, 75 g / L, 80 g / L, 85 g / L, 90 g / L, 95 g / L, 100 g / L, 105 g / L, 110 g / L and 115 g / L, or any value within the range of 55 g / L-115 g / L.

[0075] According to the preparation method provided by the present invention, in some embodiments, in step (3), the frequency of the ultrasonic oscillation is 25kHz-40kHz. It can be understood that the frequency of the ultrasonic oscillation can be any specific value among 25kHz, 26kHz, 27kHz, 28kHz, 29kHz, 30kHz, 31kHz, 32kHz, 33kHz, 34kHz, 35kHz, 36kHz, 37kHz, 38kHz, 39kHz, and 40kHz, or any value within the range of 25kHz-40kHz.

[0076] In the present invention, in step (3), suction filtration is used to remove excess high-boiling point organic solution, and the excess organic solution can be reused. According to the preparation method provided by the present invention, in some embodiments, in step (3), the mass moisture content of the second filter cake is controlled to be 140%-150%. It can be understood that the mass moisture content of the second filter cake can be any specific value of 140%, 141%, 142%, 143%, 144%, 145%, 146%, 147%, 148%, 149%, 150% or any value within the range of 140%-150%. If the moisture content of the second filter cake is too high, the drying process will cause the organic matter in the filter cake to migrate and locally aggregate, and the final carbon component distribution will be uneven; if the moisture content of the second filter cake is too low, it will cause the suction filtration to take longer.

[0077] In the present invention, the calculation formula of the filter cake mass moisture content is:

[0078] Filter cake mass moisture content (%) = (wet filter cake weight - dry filter cake weight) / dry filter cake weight × 100%

[0079] The wet filter cake is the filter cake taken out immediately after the filtration or pressure filtration is completed, and the dry filter cake is the filter cake dried in a blast drying oven under ventilation conditions at 120°C for 24 hours.

[0080] In the present invention, by controlling the timing of adding the high-boiling-point organic matter and introducing the high-boiling-point organic matter into a first filter cake having a specific water content and subjecting it to ultrasonic oscillation, the copper-zinc-aluminum precipitate particles can be broken into fine particles, allowing the high-boiling-point organic matter in the solution to be fully mixed with the precipitate fine particles. By controlling the water content of the first filter cake and the second filter cake obtained after the co-precipitation reaction, the amount of the high-boiling-point organic matter solution adsorbed by the filter cakes is controlled, thereby controlling the content of carbon produced by the decomposition of the high-boiling-point organic matter in the final product.

[0081] According to the preparation method provided by the present invention, in some embodiments, in step (4), the drying temperature is 100°C-150°C. It can be understood that the drying temperature can be any specific value among 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C, and 150°C, or any value within the range of 100°C-150°C; the drying time is 8h-24h. It can be understood that the drying time can be any specific value among 8h, 9h, 10h, 11h, 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, 21h, 22h, 23h, and 24h, or any value within the range of 8h-24h.

[0082] According to the preparation method provided by the present invention, in some embodiments, in step (4), the anaerobic roasting temperature is 350℃-450℃. It can be understood that the insulating roasting temperature can be 350℃, 355℃, 360℃, 365℃, 370℃, 375℃, 380℃, 385℃, 390℃, 395℃, 400℃, 405℃, 410℃, 415℃, 420℃, 425℃, 430℃, 440℃, 450℃, 460℃, 470℃, 480℃, 490℃, 500℃, 510℃, 520℃, 530℃, 540℃, 550℃, 560℃, 570℃, 580℃, 590℃, 600℃ Any specific value among 35℃, 440℃, 445℃, 450℃ or any value within the range of 350℃-450℃; the anaerobic roasting time is 2h-8h. It can be understood that the roasting time can be any specific value among 2h, 2.5h, 3h, 3.5h, 4h, 4.5h, 5h, 5.5h, 6h, 6.5h, 7h, 7.5h, 8h or any value within the range of 2h-8h.

[0083] According to the preparation method provided by the present invention, in some embodiments, in step (4), the amount of graphite added is 2%-6% of the mass of the second filter cake after calcination; and the amount of deionized water added is 10%-15% of the mass of the second filter cake after calcination.

[0084] Tableting is also called compression molding. The present invention has no specific restrictions on the specific method of tableting. Conventional tableting methods in the art can be used, including but not limited to using a tablet press to press into a sheet or ring shape.

[0085] In the present invention, anaerobic calcination refers to calcination performed in an oxygen-free state. The purpose of anaerobic calcination is to promote the dehydration and carbonization of high-boiling-point organic matter adsorbed in the filter cake to form carbon components. The anaerobic calcination temperature is controlled between 350°C and 450°C to ensure complete carbonization of the high-boiling-point organic matter while ensuring that the carbon components generated by carbonization do not affect the activity of the catalyst. If the calcination temperature is lower than 350°C, the high-boiling-point organic matter will not be completely carbonized, and the metal precipitate will not be completely decomposed. If the calcination temperature is higher than 450°C, the high-boiling-point organic matter will be dehydrated and carbon components will be generated. This will form hot spots in the catalyst, causing the copper grains nearby to sinter and grow, reducing the catalyst activity.

[0086] In the present invention, the carbon components generated by dehydrating and carbonizing high-boiling-point organic matter are more evenly distributed in the catalyst, which can more effectively separate the active metal grains in the catalyst and prevent them from growing during use. The generated carbon components are stable under normal use conditions of the methanol steam reforming catalyst and have no adverse effect on the catalyst activity.

[0087] The present invention also provides a methanol steam reforming catalyst prepared according to the above method, comprising components: CuO, ZnO, Al2O3, carbon components generated by decomposition of high-boiling-point organic matter, and graphite.

[0088] In the present invention, the mass percentage of CuO is 40%-65% based on the total amount of catalyst. It can be understood that its content can be any specific value of 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, and 65%, or any value within the range of 40%-65%.

[0089] In the present invention, the mass percentage of ZnO is 23%-50% based on the total amount of catalyst. It can be understood that its content can be any specific value among 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, and 50%, or any value within the range of 23%-50%.

[0090] In the present invention, the mass percentage of Al2O3 is 5%-25% based on the total amount of catalyst. It can be understood that its content can be any specific value of 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, or any value within the range of 5%-25%.

[0091] In the present invention, the mass percentage of the carbon component generated by the decomposition of the high-boiling point organic matter is 3%-6% based on the total amount of the catalyst. It can be understood that its content can be any specific value among 3%, 4%, 5%, and 6%, or any value within the range of 3%-6%.

[0092] There are many abnormal operating conditions encountered during the use of the catalyst, including but not limited to large fluctuations in pressure and temperature, pipeline blockage, etc. When the catalyst is frequently started and stopped under abnormal operating conditions, the active metal grains will grow during the repeated oxidation and reduction process of the catalyst, and the activity will drop significantly. The preparation method of the present invention can further control the content of carbon components generated by high-boiling-point organic matter in the catalyst by controlling the content of high-boiling-point organic matter, so that the carbon components can not only effectively separate the active metal grains, but also avoid excessive carbon components covering the active metal surface; at the same time, because it contains carbon components that are evenly dispersed and stable in nature, a "carbon fence" is formed, so that the active metal grains in the catalyst are evenly spaced, and cannot quickly agglomerate and grow during use. Therefore, after the operating conditions of the catalyst of the present invention fluctuate, the growth rate of the metal grains is limited because the active metal grains are evenly spaced by the carbon components. With the normal use of the catalyst, the oxidized metal grains are slowly reduced and the grains do not grow. The damaged catalyst activity can be repaired to a certain extent, thereby improving the catalyst's resistance to abnormal operating condition fluctuations and its service life.

[0093] In addition, the catalyst of the present invention contains a specific content of carbon components generated by high-boiling-point organic matter. The carbon components are evenly dispersed in the catalyst and have stable properties, so that the active metal grains in the catalyst are evenly spaced and cannot quickly agglomerate and grow during use. Therefore, the catalyst has the characteristics of high activity, good sintering resistance, and good stability. If the content of the carbon components generated by the high-boiling-point organic matter is too low, the spacing effect is not obvious; if the content of the carbon components generated by the high-boiling-point organic matter is too high, the excessive carbon particles will shield the surface of the active metal ions and affect the activity of the catalyst. At the same time, it can be observed from the SEM image that the morphology of the catalyst of the present invention before and after the catalytic reaction is uniformly distributed particles, and there is no obvious sintering phenomenon of the active components, which further illustrates that the catalyst of the present invention has good sintering resistance and activity stability.

[0094] The present invention also provides application of the catalyst in a methanol steam reforming hydrogen production process.

[0095] The reaction conditions of the methanol steam reforming hydrogen production process can refer to the existing technology, for example, the heat transfer oil temperature is 235℃-260℃, the pressure is 1.0MPa-2.0MPa, the molar ratio of raw water and methanol is 1.3-2.0, and the methanol liquid space velocity is 0.3h -1 -0.5h -1 .

[0096] The present invention will be described in detail below by way of examples. It should be understood that the following examples are only used to further explain and illustrate the present invention, and are not intended to limit the present invention.

[0097] The chemical additives used in the Examples and Comparative Examples of the present invention are all commercially available. The content of each component in the catalysts prepared in the Examples and Comparative Examples was determined using the HG / T5193-2017 Methanol to Hydrogen Catalyst Chemical Composition Analysis Method, and the carbon content was determined using a carbon-sulfur analyzer.

[0098] Example 1

[0099] The preparation method of the methanol steam reforming catalyst described in this embodiment comprises the following steps:

[0100] (1) Dissolve 483.2g of Cu(NO3)2·3H2O, 446.3g of Zn(NO3)2·6H2O and 187.6g of Al(NO3)3·9H2O in deionized water to prepare a mixed salt solution with a concentration of 1.0mol / L, and heat it to 65±5℃; dissolve sodium carbonate in deionized water to prepare a precipitant aqueous solution with a concentration of 1.0mol / L, and heat it to 65±5℃; add 4L of deionized water to a 20L glass reactor, heat it to 65±5℃, and use a peristaltic pump to add the prepared mixed salt solution and precipitant aqueous solution to the reactor in parallel, and carry out coprecipitation reaction under stirring. After 15 minutes, the mixed salt solution is added. Stir and keep the temperature at 65±5℃ and maintain pH=7.5-7.8 throughout the reaction process; continue stirring after the reaction is completed. Stop stirring when the reaction mother liquor changes from light blue to blue-green, and continue to keep the temperature at 65±5℃ for 2.5 hours to obtain a coprecipitate;

[0101] (2) The coprecipitate obtained in step (1) was filtered and washed with deionized water at 80-85°C until there was no Na + Detect and obtain the first filter cake, and control the mass moisture content of the first filter cake to be 200%;

[0102] (3) Add 3.5 L of 50 g / L polyethylene glycol 4000 solution to the reactor, transfer the first filter cake obtained in step (2) to the reactor, stir and slurry, and fully react under the action of 25 kHz-40 kHz ultrasonic vibration, then filter and remove excess solution to obtain a second filter cake, and control the mass moisture content of the second filter cake to be 150%;

[0103] (4) The second filter cake obtained in step (3) was dried at 120°C for 24 hours, and then calcined at 400°C under anaerobic conditions for 8 hours. 9.6 g of graphite and 38.4 g of deionized water were added, and the mixture was granulated and formed into tablets to obtain methanol steam reforming catalyst CAT-1.

[0104] After testing, in the methanol steam reforming catalyst cat-1 prepared in this embodiment, the mass proportion of CuO is 48.3%, the mass proportion of ZnO is 37.1%, the mass proportion of Al2O3 is 7.7%, the mass proportion of carbon components generated by decomposition of high-boiling point organic matter is 4.0%, and the balance is graphite.

[0105] Example 2

[0106] The method for preparing the methanol steam reforming catalyst described in this embodiment comprises the following steps:

[0107] (1) Dissolve 483.2g of Cu(NO3)2·3H2O, 297.5g of Zn(NO3)2·6H2O and 626g of Al(NO3)3·9H2O in deionized water to prepare a mixed salt solution with a concentration of 0.5mol / L, and heat it to 65±5℃; dissolve sodium carbonate in deionized water to prepare a precipitant aqueous solution with a concentration of 0.5mol / L, and heat it to 65±5℃; add 4L of deionized water to a 20L glass reactor, heat it to 65±5℃, and use a peristaltic pump to add the prepared mixed salt solution and precipitant aqueous solution to the reactor in parallel, and carry out coprecipitation reaction under stirring. After 15 minutes, the mixed salt solution is added. Stir and keep the temperature at 65±5℃ and maintain pH=7.5-7.8 throughout the reaction process; continue stirring after the reaction is completed, and stop stirring when the reaction mother liquor changes from light blue to blue-green, and continue to keep the temperature at 65±5℃ for 2.5 hours to obtain a coprecipitate;

[0108] (2) The coprecipitate obtained in step (1) was filtered and washed with deionized water at 80-85°C until there was no Na + Detect and obtain the first filter cake, and control the mass moisture content of the first filter cake to be 150%;

[0109] (3) Add 3.0 L of 40 g / L polyethylene glycol 4000 solution to the reactor, transfer the first filter cake obtained in step (2) to the reactor, stir and slurry, and fully react under the action of 25 kHz-40 kHz ultrasonic vibration, then filter and remove excess solution to obtain a second filter cake, and control the mass moisture content of the second filter cake to be 140%;

[0110] (4) The second filter cake obtained in step (3) was dried at 120°C for 24 hours, and then calcined at 450°C under anaerobic conditions for 8 hours. 13.5 g of graphite and 33.6 g of deionized water were added, and the mixture was granulated and formed into tablets to obtain methanol steam reforming catalyst CAT-2.

[0111] After testing, in the methanol steam reforming catalyst cat-2 prepared in this embodiment, the mass proportion of CuO is 45.5%, the mass proportion of ZnO is 23.3%, the mass proportion of Al2O3 is 24.3%, the mass proportion of carbon components generated by decomposition of high-boiling point organic matter is 3.0%, and the balance is graphite.

[0112] Example 3

[0113] The method for preparing the methanol steam reforming catalyst described in this embodiment comprises the following steps:

[0114] (1) The steps for preparing the coprecipitate are the same as those in Example 1;

[0115] (2) The coprecipitate obtained in step (1) was filtered and washed with deionized water at 80-85°C until there was no Na+ Detect and obtain the first filter cake, and control the mass moisture content of the first filter cake to be 180%;

[0116] (3) Add 2.5 L of 80 g / L polyethylene glycol 4000 solution to the reactor, transfer the first filter cake obtained in step (2) to the reactor, stir and slurry, and after sufficient reaction under the action of 25 kHz-40 kHz ultrasonic vibration, remove the excess solution by suction to obtain a second filter cake, and control the mass moisture content of the second filter cake to be 150%;

[0117] (4) The second filter cake obtained in step (3) was dried at 120°C for 24 hours, and then calcined at 350°C under anaerobic conditions for 8 hours. 9.8 g of graphite and 42.5 g of deionized water were added, and the mixture was granulated and formed into tablets to obtain methanol steam reforming catalyst CAT-3.

[0118] After testing, in the methanol steam reforming catalyst cat-3 prepared in this embodiment, the mass proportion of CuO is 47.3%, the mass proportion of ZnO is 36.3%, the mass proportion of Al2O3 is 7.6%, the mass proportion of carbon components generated by decomposition of high-boiling point organic matter is 6.0%, and the balance is graphite.

[0119] Example 4

[0120] The preparation method of the methanol steam reforming catalyst described in this embodiment comprises the following steps:

[0121] (1) Dissolve 399.3g Cu(CH3COOH)2·H2O, 329.3g Zn(CH3COOH)2·2H2O, and 187.6g Al(NO3)3·9H2O in deionized water to prepare a 1.5mol / L mixed salt solution, and heat it to 65±5℃; dissolve sodium carbonate in deionized water to prepare a 1.5mol / L precipitant solution, and heat it to 65±5℃; add 20L glass reactor to the mixture. 4 L of deionized water was added to the kettle and heated to 65 ± 5 ° C. The prepared mixed salt solution and the precipitant aqueous solution were added to the reactor in parallel using a peristaltic pump. The coprecipitation reaction was carried out under stirring. The mixed salt solution was added after 15 minutes. The reaction was stirred and kept at 65 ± 5 ° C and pH = 7.5-7.8 throughout the reaction. Stirring was continued after the reaction was completed. When the reaction mother liquor turned from light blue to blue-green, stirring was stopped. The mixture was kept at 65 ± 5 ° C for 2.5 hours to obtain a coprecipitate.

[0122] (2) The coprecipitate obtained in step (1) was filtered and washed with deionized water at 80-85°C until there was no Na + Detect and obtain the first filter cake, and control the mass moisture content of the first filter cake to be 200%;

[0123] (3) Add 3.5 L of 70 g / L polyethylene glycol 4000 solution to the reactor, transfer the first filter cake obtained in step (2) to the reactor, stir and slurry, and fully react under the action of 25 kHz-40 kHz ultrasonic vibration, then filter to remove excess solution to obtain a second filter cake, and control the mass moisture content of the second filter cake to be 150%;

[0124] (4) The second filter cake obtained in step (3) was dried at 120°C for 24 hours, and then calcined at 400°C under anaerobic conditions for 8 hours. 19.5 g of graphite and 48.8 g of deionized water were added, and the mixture was granulated and formed into tablets to obtain methanol steam reforming catalyst CAT-4.

[0125] After testing, in the methanol steam reforming catalyst cat-4 prepared in this embodiment, the mass proportion of CuO is 46.1%, the mass proportion of ZnO is 35.4%, the mass proportion of Al2O3 is 7.4%, the mass proportion of carbon components generated by decomposition of high-boiling point organic matter is 5.4%, and the balance is graphite.

[0126] Comparative Example 1

[0127] The preparation method of the methanol steam reforming catalyst described in this comparative example has the same preparation steps as Example 1, except that the anaerobic calcination in step (4) is replaced by calcination in an air atmosphere at 400°C to prepare the methanol steam reforming catalyst D-cat-1.

[0128] According to the test, the mass of the carbon components generated by decomposition of high-boiling-point organic matter in the methanol steam reforming catalyst D-cat-1 prepared in this comparative example accounts for 0.4%.

[0129] Comparative Example 2

[0130] The preparation method of the methanol steam reforming catalyst described in this comparative example has the same preparation steps as Example 1, except that ultrasonic oscillation is not used in step (3) to prepare the methanol steam reforming catalyst D-cat-2.

[0131] According to testing, the mass of carbon components generated by decomposition of high-boiling-point organic matter in the methanol steam reforming catalyst D-cat-2 prepared in this comparative example accounts for 4.0%.

[0132] Comparative Example 3

[0133] The method for preparing the methanol steam reforming catalyst described in this comparative example comprises the following steps:

[0134] (1) The steps for preparing the coprecipitate are the same as those in Example 1;

[0135] (2) The coprecipitate obtained in step (1) was filtered and washed with deionized water at 80-85°C until there was no Na +Detect and obtain the first filter cake, and control the moisture content of the first filter cake to be 200%;

[0136] (3) washing the first filter cake obtained in step (2) with a 45 g / L polyethylene glycol 4000 solution, removing excess solution by suction filtration to obtain a second filter cake, and controlling the moisture content of the second filter cake to be 150%;

[0137] (4) The second filter cake obtained in step (3) was dried at 120°C for 24 hours, and then calcined at 400°C under anaerobic conditions for 8 hours. 6.7 g of graphite and 33.2 g of deionized water were added, and the mixture was granulated and formed into tablets to obtain methanol steam reforming hydrogen production catalyst D-cat-3.

[0138] According to testing, the mass of carbon components generated by decomposition of high-boiling-point organic matter in the methanol steam reforming catalyst D-cat-3 prepared in this comparative example accounts for 4.0%.

[0139] Comparative Example 4

[0140] The method for preparing the methanol steam reforming catalyst described in this comparative example comprises the following steps:

[0141] (1) The steps for preparing the coprecipitate are the same as those in Example 1;

[0142] (2) The coprecipitate obtained in step (1) was filtered and washed with deionized water at 80-85°C until there was no Na + Detect and obtain filter cake;

[0143] (3) The filter cake obtained in step (2) was dried at 120°C for 24 h, 29.5 g of polyethylene glycol 4000 was added, the mixture was crushed to less than 200 mesh, and calcined at 400°C under anaerobic conditions for 8 h. 6.7 g of graphite and 33.2 g of deionized water were added, and the mixture was granulated and formed into tablets to obtain methanol steam reforming hydrogen production catalyst D-cat-4.

[0144] According to testing, the mass of carbon components generated by decomposition of high-boiling-point organic matter in the methanol steam reforming catalyst D-cat-4 prepared in this comparative example accounts for 4.0%.

[0145] Comparative Example 5

[0146] The method for preparing the methanol steam reforming catalyst described in this comparative example comprises the following steps:

[0147] (1) The steps for preparing the coprecipitate are the same as those in Example 1;

[0148] (2) The coprecipitate obtained in step (1) was filtered and washed with deionized water at 80-85°C until there was no Na + Detect and obtain filter cake;

[0149] (3) The filter cake obtained in step (2) was dried at 120°C for 24 h, mixed evenly with a paste prepared by mixing 50 g of deionized water and 29.5 g of polyethylene glycol 4000, and calcined at 400°C under anaerobic conditions for 8 h. 6.7 g of graphite and 33.2 g of deionized water were added, and the mixture was granulated and formed into tablets to obtain methanol steam reforming catalyst D-cat-5.

[0150] According to testing, the mass of carbon components generated by decomposition of high-boiling-point organic matter in the methanol steam reforming catalyst D-cat-5 prepared in this comparative example accounts for 4.0%.

[0151] Comparative Example 6

[0152] The preparation method of the methanol steam reforming catalyst described in this comparative example comprises the following steps:

[0153] (1) The steps for preparing the coprecipitate are the same as those in Example 1;

[0154] (2) The coprecipitate obtained in step (1) was filtered and washed with deionized water at 80-85°C until there was no Na + Detect and obtain filter cake;

[0155] (3) The filter cake obtained in step (2) was dried at 120°C for 24 h, and then calcined at 400°C under anaerobic conditions for 8 h. 6.7 g of graphite and 33.2 g of deionized water were added, and the mixture was granulated and formed into tablets to obtain methanol steam reforming catalyst D-cat-6.

[0156] In this comparative example, no high-boiling-point organic matter was added, so the mass proportion of the carbon component generated by decomposition of the high-boiling-point organic matter in the catalyst was 0.

[0157] Comparative Example 7

[0158] The preparation method of the methanol steam reforming catalyst described in this comparative example has the same preparation steps as those in Example 1, except that the moisture content of the first filter cake and the second filter cake in steps (2) and (3) are both controlled to be 130%, thereby obtaining the methanol steam reforming catalyst D-cat-7.

[0159] According to testing, the mass of carbon components generated by decomposition of high-boiling-point organic matter in the methanol steam reforming catalyst D-cat-7 prepared in this comparative example accounts for 3.8%.

[0160] Comparative Example 8

[0161] The preparation method of the methanol steam reforming catalyst described in this comparative example has the same preparation steps as Example 1, except that the temperature of the anaerobic calcination in step (3) is 500°C, and the methanol steam reforming catalyst D-cat-8 is prepared.

[0162] According to testing, the mass of carbon components generated by decomposition of high-boiling-point organic matter in the methanol steam reforming catalyst D-cat-8 prepared in this comparative example accounts for 4.0%.

[0163] The heat resistance performance of the methanol steam reforming catalysts prepared in the above examples and comparative examples was evaluated. The specific steps are as follows:

[0164] A fixed-bed reactor with a φ22 mm inner diameter was used. The catalyst was loaded into the reactor tubes, containing 100 mL of catalyst. Thermal oil heating was used. The reduction medium consisted of deionized water and 2% methanol. The thermal oil temperature was ramped from 200°C for 12 h to 220°C for 2 h to 240°C for 6 h. The reduction pressure was atmospheric pressure. After the reduction process, the thermal oil temperature was raised to 255°C, the reaction pressure was 1.3 MPa, the water flow rate was 0.71 g / min, and the methanol flow rate was 0.658 g / min. Under these conditions, the initial activity was measured after 24 hours of reaction. Heat aging was then performed by raising the thermal oil temperature to 270°C for 10 hours, followed by cooling to 255°C. After 24 hours of operation, the reaction activity was measured as the post-heat aging activity. The methanol content in the liquid product and the composition of the reaction exhaust were analyzed by gas chromatography. Methanol analysis was performed using the following chromatographic conditions: a GC-14B gas chromatograph, a Φ3 mm × 2 m GDX-102 column, a column temperature of 90°C, a TCD detector at a detection temperature of 150°C, high-purity H₂ as the carrier gas, a carrier flow rate of 30 mL / min, and normalization. Exhaust gas composition was analyzed using the following chromatographic conditions: a GC-14B gas chromatograph, a Φ3 mm × 2 m GDX-104 column, a column temperature of 100°C, a TCD detector at a detection temperature of 40°C, high-purity H₂ as the carrier gas, a carrier flow rate of 30 mL / min, and an external standard method. Catalyst activity was measured as methanol single-pass conversion.

[0165] The activity retention rate of the catalyst is calculated by the following formula, and the specific performance test results of the catalyst are shown in Table 1.

[0166] Catalyst activity retention rate (%) = activity after heat resistance (%) / initial activity (%) × 100%

[0167] Table 1 Test results of catalyst performance of examples and comparative examples

[0168] .

[0169] As can be seen from the examples and comparative examples, the catalyst activity retention rates prepared in the examples of the present invention are all above 98%, which is significantly better than the catalyst prepared by the comparative method. As can be seen from Example 1 and Comparative Examples 1-2, Comparative Example 1 is calcined under an air atmosphere, and the mass ratio of the carbon components generated by the decomposition of high-boiling-point organic matter in the catalyst finally obtained is only 0.4%, and the activity retention rate of the catalyst is less than 90%; Comparative Example 2 does not use ultrasonic vibration during stirring and beating. Although the mass ratio of the carbon components generated by the decomposition of high-boiling-point organic matter in the catalyst is 4%, the activity retention rate of the catalyst is only 92% because the high-boiling-point organic matter cannot be fully mixed with the sediment particles. In Comparative Examples 3-5, the addition method of polyethylene glycol is different, and the activity retention rate of the catalyst finally obtained is lower than that of the examples, indicating that the addition method of high-boiling-point organic matter has a greater impact on the activity retention rate of the catalyst. The method in Comparative Example 6 does not use high-boiling-point organic matter, and the activity retention rate of the catalyst is less than 90%. The moisture content of the first and second filter cakes in Comparative Example 7 is low, and the activity retention rate of the catalyst is also lower than that of the catalyst in the examples. In Comparative Example 8, the temperature of the anaerobic calcination was too high, and the initial activity of the catalyst was obviously too low.

[0170] from Figure 1 (a) Figure 1 (b) It can be seen that the catalyst prepared in Example 1 of the present invention exhibits uniformly distributed granular morphology before and after the reaction, with no apparent sintering of the active components, indicating good sintering resistance and stability. In contrast, the catalyst prepared in the comparative example exhibits a coexistence of flakes and granules before the reaction. After the reaction, the catalyst undergoes a significant morphology change, with numerous rod-like structures appearing. This indicates sintering of the active components, which may be the cause of the decreased catalyst activity and stability.

[0171] The catalyst in Example 1 was subjected to an abnormal operating condition simulation evaluation, and the specific steps are as follows:

[0172] A tubular fixed-bed reactor was used, with the catalyst loaded into it. The reactor tube had an inner diameter of 22 mm and a catalyst loading of 100 mL. The reactor was heated using tubular thermal oil. The reduction medium was deionized water + 2% methanol. The thermal oil temperature ramped from 200°C for 12 hours to 220°C for 2 hours to 240°C for 6 hours. The reduction pressure was atmospheric pressure. After the reduction process was complete, normal operation resumed. Normal operating conditions included a thermal oil temperature of 255°C, a reaction pressure of 1.3 MPa, a water flow rate of 0.71 g / min, and a methanol flow rate of 0.658 g / min. Abnormal operating conditions included disconnecting the power supply, stopping the water, methanol, and heating, purging the bed with 99% nitrogen, maintaining the pressure at 0.5 MPa, and cooling to ambient temperature. The restart conditions are: the heat transfer oil is heated to 255℃, methanol water solution is introduced, the reaction pressure is 1.3MPa, the water volume is 0.71g / min, the methanol volume is 0.658g / min, and normal operation is carried out. This is repeated three times, each operation is about 100h, and sampling and analysis are performed every 8h. The analysis method is the same as the heat resistance performance evaluation. The specific evaluation results are shown in Figure 8 .

[0173] from Figure 8 It can be seen that each time the catalyst was restarted after abnormal operating conditions, the catalyst activity decreased significantly. However, after approximately 50 hours of normal operation, the catalyst activity recovered significantly. After experiencing three abnormal operating conditions, the catalyst activity finally recovered and remained above 96% of its initial activity, demonstrating that the catalyst of this invention has excellent resistance to fluctuations under abnormal operating conditions.

[0174] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for preparing a methanol steam reforming catalyst, characterized in that: The steps include: (1) A mixed salt solution containing soluble copper salt, soluble zinc salt, and soluble aluminum salt and a precipitant aqueous solution are co-precipitated in parallel, and the solution is aged after its color changes from light blue to blue-green to obtain a co-precipitate; (2) Wash the coprecipitate until it is free of Na + Detection to obtain a first filter cake, wherein the mass moisture content of the first filter cake is 150%-200%; (3) Under ultrasonic vibration conditions, the first filter cake and the high-boiling point organic aqueous solution are stirred and slurried, and filtered to obtain a second filter cake, wherein the mass moisture content of the second filter cake is 140%-150%; (4) drying the second filter cake, calcining it in an oxygen-free state, adding graphite and deionized water, and forming it into tablets to obtain the methanol steam reforming catalyst; In step (3), the high-boiling-point organic matter includes one or more of carbohydrates and polyhydroxy organic matter, and the concentration of the high-boiling-point organic matter aqueous solution is 40 g / L-115 g / L; the carbohydrates include one or more of glucose, sucrose, lactose, and soluble starch; the polyhydroxy organic matter includes one or more of ethylene glycol, glycerol, and polyethylene glycol; In step (4), the anaerobic roasting temperature is 350°C-450°C, and the anaerobic roasting time is 2h-8h; The methanol steam reforming catalyst comprises the following components in terms of mass percentage based on its total amount: CuO40%-65%; ZnO23%-50%; Al2O35%-25%; 3%-6% of the carbon component is generated by the decomposition of high-boiling point organic matter; and the balance is graphite.

2. The method for preparing a methanol steam reforming catalyst according to claim 1, wherein: In step (1), the soluble copper salt includes one or more of copper nitrate, copper oxalate, and copper acetate; the soluble zinc salt includes one or more of zinc nitrate, zinc oxalate, and zinc acetate; the soluble aluminum salt is aluminum nitrate; and the precipitant includes one or more of sodium hydroxide, sodium carbonate, and sodium bicarbonate.

3. The method for preparing a methanol steam reforming catalyst according to claim 1, wherein: In step (1), the concentration of the mixed salt solution is 0.5 mol / L-1.5 mol / L, and the concentration of the precipitant aqueous solution is 0.5 mol / L-1.5 mol / L.

4. The method for preparing a methanol steam reforming catalyst according to claim 1, wherein: In step (1), the coprecipitation reaction conditions are: under stirring, the reaction temperature is controlled at 60°C-70°C, and the pH is 7.5-7.8; the aging conditions are: the aging temperature is 60°C-70°C, and the aging time is 1.5h-8h.

5. The method for preparing a methanol steam reforming catalyst according to claim 1, wherein: In step (2), the washing is performed by suction filtration or pressure filtration using deionized water, and the temperature of the deionized water is 80° C.-85° C.

6. The method for preparing a methanol steam reforming catalyst according to claim 1, wherein: In step (4), the drying temperature is 100°C-150°C, and the drying time is 8h-24h.

7. Use of the catalyst prepared according to the preparation method according to any one of claims 1 to 6 in a methanol steam reforming hydrogen production process.

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