Hydrocarbon steam conversion catalyst and preparation method and application thereof

Abstract

The invention provides a hydrocarbon steam reforming catalyst and a preparation method and application thereof, and belongs to the technical field of hydrocarbon steam reforming hydrogen production, and the hydrocarbon steam reforming catalyst comprises a nickel oxide active component, kapok, nickel aluminate, alpha-Al2O3, CaO and calcium aluminate cement. The hydrocarbon steam reforming catalyst is rich in pore structure, large in specific surface area and rich in caramel and nickel aluminate components, the caramel and the nickel aluminate components have a good synergistic effect on generation and transportation of active oxygen, and the catalyst is high in activity, good in carbon deposition resistance and good in stability; the preparation method provided by the invention does not need additional addition of auxiliaries, and is simple in preparation process, easy to operate, good in repeatability and suitable for large-scale industrial application.

Description

Technical Field

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

[0002] Hydrogen is efficient, environmentally friendly and has a wide range of uses. Against the backdrop of increasingly stringent environmental protection laws and "carbon peak and carbon neutrality", hydrogen energy has obvious advantages over traditional energy and has broad application prospects.

[0003] At present, the commonly used hydrogen production methods in industry mainly include hydrocarbon steam reforming hydrogen production, coal hydrogen production, methanol hydrogen production, etc., and hydrocarbon steam reforming hydrogen production is the most widely used hydrogen production method in industry due to its advantages such as low investment, mature and reliable process, flexible and convenient operation, and low cost. The reforming catalyst is the core of the hydrocarbon steam reforming hydrogen production device. The most commonly used reforming catalyst is mainly a nickel-based catalyst with relatively low price and excellent activity. However, traditional nickel-based catalysts are prone to carbon deposition and sintering at high temperatures. How to overcome the shortcomings of existing nickel-based catalysts and improve the activity and stability of nickel-based catalysts is the current research focus.

[0004] The water-carbon ratio is extremely important in the hydrocarbon steam reforming reaction. Water vapor can react with carbon deposits on the catalyst, so increasing the water-carbon ratio can greatly reduce the carbon deposition on the catalyst. However, too high a water-carbon ratio can also bring some adverse effects, such as increasing the energy consumption of the device, increasing the pressure difference of the reformer, and increasing the growth rate of nickel grains, which is not conducive to the stability of the reaction system.

[0005] Katoite (with the general molecular formula of Ca3Al2(SiO4)3-x(OH)4x, x=1.5-3) can be obtained from the final hydrated stable phase of calcium aluminate, etc. Among them, katoite Ca3Al2(O4H4)3, that is, when x is 3, all (SiO4)4- groups are replaced by (O4H4)4+ groups, has a considerable content of OH-, and can generate H2O by decomposition: Ca3Al2(O4H4)3 = 3Ca(OH)2 + Al2O3 + 3H2O In the relevant literature, there have been reports on the structure and properties of katoite. For example, Masato Kato et al. studied the structural behavior changes of katoite under high pressure and high temperature, see the literature "Structural behavior of hydrogarnet, katoite Ca3Al2 (O4H4) 3, under high pressure and high temperature (abs.). Japan Association of Mineralogical Sciences, 2016, 108". H. Olijnyk et al. systematically studied the structure and properties of katoite using EDXRD spectroscopy, see the literature "Compressional study of katoite [Ca3Al2 (O4H4) 3] and grossular garnet. Physics and Chemistry of Minerals and Rocks Volcanology, 1991, 96, 14313-14318". However, the technology of using katoite as a catalyst component has not been fully studied, and it is still rare to use it for hydrocarbon steam reforming reactions. Summary of the invention

[0006] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a hydrocarbon steam reforming catalyst having the characteristics of large specific surface area, high activity, good resistance to carbon deposition and good stability; the present invention also provides a preparation method thereof, which does not require the addition of additional additives, has a simple preparation process, is easy to operate and has good repeatability, and is suitable for large-scale industrial applications.

[0007] In order to achieve the above object, according to one aspect of the present invention, a hydrocarbon steam reforming catalyst is provided, which comprises the following components by weight, calculated on a total basis: Nickel oxide active component 8wt%-20wt%; Catonite 5wt%-10wt%; Nickel aluminate 10wt%-15wt%; ɑ-Al2O3 35wt%-45wt%; CaO 15wt%-25wt%.

[0008] In some embodiments, the pore volume of the catalyst is ≥ 0.15 mL / g.

[0009] In some embodiments, the bulk density of the catalyst is 0.80 kg / L-1.20 kg / L.

[0010] In some embodiments, the specific surface area of ​​the catalyst is ≥ 60 m2 / g.

[0011] In some embodiments, the lateral compression strength of the catalyst is greater than 300 N / particle.

[0012] In some embodiments, the catalyst is in the shape of a porous sphere or column; preferably, the catalyst is in the shape of a Raschig ring, a four-hole cylinder, a seven-hole cylinder, or a seven-rib wheel.

[0013] According to another aspect of the present invention, there is also provided a method for preparing the hydrocarbon steam reforming catalyst as described above, comprising the following steps: (1) taking γ-Al2O3, calcium aluminate cement, and calcium carbonate according to their mass content, adding a binder and a pore-enlarging agent, mixing them thoroughly, and pressing them into a shape to obtain a carrier to be calcined; (2) calcining the carrier to be calcined obtained in step (1) once, immersing the calcined carrier in deionized water at a specific temperature for quenching, calcining the quenched carrier for a second time, and cooling to obtain a cooled carrier; (3) placing the cooled support obtained in step (2) into a nickel nitrate solution and performing a first impregnation under ultrasonic conditions, drying the impregnated catalyst and placing it again into the nickel nitrate solution and performing a second impregnation under ultrasonic conditions; (4) placing the catalyst obtained in step (3) after the secondary impregnation into a muffle furnace for primary calcination, immersing the calcined catalyst in deionized water at a specific temperature for quenching, calcining the quenched catalyst for a secondary time, and naturally cooling it to room temperature to obtain the hydrocarbon steam reforming catalyst.

[0014] In some embodiments, in step (1), the calcium aluminate cement is pure calcium aluminate cement; preferably, in terms of weight percentage, the calcium aluminate cement comprises 72%-82% Al2O3 and 18%-23% CaO.

[0015] In some embodiments, in step (1), the weight ratio of γ-Al2O3, calcium aluminate cement and calcium carbonate is γ-Al2O3: calcium aluminate cement: calcium carbonate = 1: (1.2-1.4): (0.2-0.4).

[0016] In some embodiments, in step (1), the binder is selected from graphite binders.

[0017] In some embodiments, in step (1), the pore-forming agent is selected from one or more of carbon powder, nitrates, and carbonates.

[0018] In some embodiments, in step (1), the mixing method is ball milling, and the ball milling time is 2-4 hours.

[0019] In some embodiments, in step (2), the primary calcination is carried out in a nitrogen and water vapor mixed atmosphere, preferably, the nitrogen and water vapor mixing ratio is N2:H2O=1:(0.4-0.6); the primary calcination temperature is 1300°C-1550°C, and the primary calcination time is 4h-8h.

[0020] In some embodiments, in step (2), the quenching refers to immediately immersing the calcined carrier in deionized water. Preferably, the temperature of the deionized water is 15°C-150°C, and the quenching time is 10min-30min.

[0021] In some embodiments, in step (2), the secondary calcination is performed in a nitrogen atmosphere. Preferably, the secondary calcination temperature is 1000°C-1350°C, and the secondary calcination time is 10 min-30 min.

[0022] In some embodiments, in step (3), the frequency of the ultrasound is 20kHz-60kHz.

[0023] In some embodiments, in step (3), the immersion time is 30 min-60 min.

[0024] In some embodiments, in step (3), the drying temperature is 120°C-180°C, and the drying time is 8h-24h.

[0025] In some embodiments, in step (3), the secondary immersion time is 30 min-60 min.

[0026] In some embodiments, in step (4), the primary calcination temperature is 350°C-550°C, and the primary calcination time is 2h-8h.

[0027] In some embodiments, the quenching refers to immediately immersing the calcined catalyst in deionized water. Preferably, the temperature of the deionized water is 15° C.-150° C., and the quenching time is 10 min-30 min.

[0028] In some embodiments, the secondary calcination temperature is 1000° C.-1350° C., and the secondary calcination time is 10 min-30 min.

[0029] According to another aspect of the present invention, the present invention also provides the use of the above catalyst or the catalyst prepared by the above preparation method in a hydrocarbon steam reforming process.

[0030] In some embodiments, the catalyst is suitable for a hydrocarbon steam reforming process with a reformer inlet temperature of 400°C - 600°C, an outlet temperature of 700°C - 850°C, a reforming carbon space velocity of 600h-1 - 1000h-1, a water-carbon ratio of 2.0 - 4.5, and a pressure of 2.0MPa - 4.0MPa, for producing hydrogen.

[0031] The beneficial effects of the present invention are as follows: The hydrocarbon steam reforming catalyst of the present invention has a rich pore structure, a large specific surface area, and contains abundant catorite and nickel aluminate components, which have a good synergistic effect on the generation and transportation of active oxygen, and has high catalyst activity, good anti-coking performance and good stability. At the same time, the preparation method provided by the present invention does not require the addition of additional additives, has a simple preparation process, is easy to operate and has good repeatability, and is suitable for large-scale industrial applications.

[0032] Compared with the prior art, the advantages and positive effects of the present invention are: The hydrocarbon steam reforming catalyst of the present invention utilizes two quenching processes of the carrier and the catalyst, and through a huge temperature difference and a rapid temperature change, causes the deionized water in the catalyst pores to instantly undergo a phase change and vaporize into water vapor. The water vapor rapidly expands in the pores, greatly increasing the number of mesoporous structures of the catalyst, and improving the specific surface area of ​​the catalyst and the dispersion of the active component nickel.

[0033] The hydrocarbon steam reforming catalyst of the present invention has a calcination and quenching step during carrier preparation to generate a catorite component containing a large amount of OH- and active oxygen in the carrier, and a calcination and quenching step after impregnation with nickel nitrate to generate a nickel aluminate component in the catalyst, which is beneficial for transmitting active oxygen. The synergistic effect of the two is beneficial for inhibiting the carbonization of the catalyst, and can oxidize the carbon deposits already formed on the catalyst into CO and CO2, thereby enhancing the anti-carbon performance of the catalyst and improving the stability and life of the catalyst.

[0034] The composition, structure and carrier amount of the hydrocarbon steam reforming catalyst of the present invention can be adjusted according to demand. Compared with the hydrocarbon steam reforming catalyst prepared by the traditional impregnation method, the hydrocarbon steam reforming catalyst prepared by the present invention does not need to add additional carbon-resistant potash additives, which reduces the impact on the catalyst activity and does not have the risk of potash loss affecting the downstream. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein: Figure 1 This is the XRD pattern of the catalyst prepared in Example 1 of the present invention.

[0036] Figure 2Schematic diagram of the flow of the fixed bed reactor of the micro atmospheric pressure evaluation device used for evaluating catalyst activity.

[0037] The reference numerals in the figure are as follows: 1 mass flow meter 1, 2 mass flow meter 2, 3 pump, 4 preheater, 5 mixer, 6 reactor, 7 cooler, 8 gas-liquid separation unit. DETAILED DESCRIPTION

[0038] In order to enable those skilled in the art to understand the characteristics and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used in the text are the common meanings understood by those skilled in the art for the present invention. In the event of a conflict, the definition in this specification shall prevail.

[0039] In this article, unless otherwise specified, catonite refers to catonite without silicon, and its molecular formula is Ca3Al2(O4H4)3.

[0040] 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.

[0041] Herein, when describing embodiments or examples, it should be understood that they are not used to limit the present invention to these embodiments or examples. On the contrary, all substitutes, improvements and equivalents of the methods and materials described in the present invention can be included in the scope limited by the claims.

[0042] In this document, in order to make the description concise, not all possible combinations of various technical features in various embodiments or examples are described. Therefore, as long as there is no contradiction in the combination of these technical features, the various technical features in various embodiments or examples can be combined arbitrarily, and all possible combinations should be considered to be within the scope of this specification.

[0043] The invention provides a hydrocarbon steam reforming catalyst, which comprises components: nickel oxide active component, catonite, nickel aluminate, α-Al2O3, CaO and calcium aluminate cement.

[0044] In the present invention, the active component nickel in the catalyst is measured in the form of nickel oxide. Therefore, in the present invention, the nickel oxide active component is nickel oxide. The mass percentage of the nickel oxide active component is the mass percentage of nickel oxide.

[0045] In the present invention, the mass percentage of the nickel oxide active component is 8%-20% based on the total amount of the catalyst. It can be understood that its content can be any specific value among 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20% or any value within the range of 8%-20%.

[0046] In the present invention, the mass percentage of the catonite is 5%-10% based on the total amount of catalyst. It is understandable that the content can be any specific value of 5%, 6%, 7%, 8%, 9%, 10% or any value within the range of 5%-10%.

[0047] In the present invention, the molecular formula of catonite is Ca3Al2(O4H4)3, and the structure of catonite contains a considerable amount of OH-, and OH- contains a large amount of active oxygen, which can provide oxygen to the active metal components in the catalyst. In addition, the decomposition of catonite can generate H2O. The large amount of OH- in the catonite and the generated H2O achieve the effect of increasing the water-carbon ratio. The high active oxygen content can re-oxidize the C deposited on the catalyst into CO and CO2, thereby improving the anti-coking performance of the catalyst, thereby improving the stability of the catalyst and extending its service life.

[0048] In the present invention, the mass percentage of the nickel aluminate is 10%-15% based on the total amount of the catalyst. It can be understood that the content can be any specific value of 10%, 11%, 12%, 13%, 14%, 15% or any value within the range of 10%-15%.

[0049] In the present invention, the Ni generated by the reduction of nickel aluminate has a strong interaction with the carrier, and the degree of its inhibition of coking and sintering is higher, which is conducive to the stability of Ni particles at high temperatures. In addition, in a reducing atmosphere, the reduction of Ni in nickel aluminate not only produces Ni / Al2O3, but also forms a defective phase NiAlxOy due to the lack of stoichiometry, which has a higher oxygen surface mobility. At the same time, nickel aluminate and the catorite component containing a large amount of active oxygen produce a synergistic effect, further improving its anti-coking performance, and improving the activity, stability and life of the catalyst.

[0050] In the present invention, based on the total amount of catalyst, the mass percentage of α-Al2O3 is 35%-45%. It can be understood that its content can be any specific value of 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45% or any value within the range of 35%-45%.

[0051] In the present invention, the mass percentage of CaO is 15%-25% based on the total amount of catalyst. It can be understood that the content can be any specific value of 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25% or any value within the range of 15%-25%.

[0052] In the present invention, the pore volume of the catalyst is not less than 0.15 mL / g, preferably not less than 0.2 mL / g.

[0053] In the present invention, the bulk density of the catalyst is 0.80 kg / L-1.20 kg / L, preferably 1.00 kg / L-1.10 kg / L.

[0054] In the present invention, the specific surface area of ​​the catalyst is not less than 60m2 / g, preferably not less than 65m2 / g.

[0055] In the present invention, the lateral compression strength of the catalyst is greater than 300 N / particle, preferably greater than 350 N / particle.

[0056] In the present invention, the catalyst is in the shape of a porous sphere or column; preferably, the catalyst is in the shape of a Raschig ring, a four-hole cylinder, a seven-hole cylinder, or a seven-rib wheel.

[0057] The present invention also provides a method for preparing a hydrocarbon steam reforming catalyst, which comprises the following steps: (1) taking γ-Al2O3, calcium aluminate cement, and calcium carbonate according to their mass content, adding a binder and a pore-enlarging agent, mixing them thoroughly, and pressing them into a shape to obtain a carrier to be calcined; (2) calcining the carrier to be calcined obtained in step (1) once, immersing the calcined carrier in deionized water at a specific temperature for quenching, calcining the quenched carrier for a second time, and cooling to obtain a cooled carrier; (3) placing the cooled support obtained in step (2) into a nickel nitrate solution and performing a first impregnation under ultrasonic conditions, drying the impregnated catalyst and placing it again into the nickel nitrate solution and performing a second impregnation under ultrasonic conditions; (4) placing the catalyst obtained in step (3) after the secondary impregnation into a muffle furnace for primary calcination, immersing the calcined catalyst in deionized water at a specific temperature for quenching, calcining the quenched catalyst for a secondary time, and naturally cooling it to room temperature to obtain the hydrocarbon steam reforming catalyst.

[0058] According to the preparation method provided by the present invention, in step (1), the calcium aluminate cement is pure calcium aluminate cement; preferably, in terms of weight percentage, the calcium aluminate cement comprises 72%-82% Al2O3 and 18%-23% CaO.

[0059] According to the preparation method provided by the present invention, in step (1), the weight ratio of γ-Al2O3, calcium aluminate cement and calcium carbonate is γ-Al2O3: calcium aluminate cement: calcium carbonate = 1: (1.2-1.4): (0.2-0.4), preferably 1: 1.3: 0.3; the catalyst prepared by the ratio of the present invention has higher activity and better performance in all aspects.

[0060] According to the preparation method provided by the present invention, in step (1), the binder is selected from graphite binders, preferably graphite.

[0061] According to the preparation method provided by the present invention, in step (1), the pore-forming agent is selected from one or more of carbon powder, nitrates, and carbonates, preferably, selected from one or more of sesbania powder and carbon powder.

[0062] According to the preparation method provided by the present invention, the weight ratio of the binder and the pore former to γ-Al2O3 is (0.05-0.15): 1, preferably (0.1-0.15): 1. The binder and the pore former of the present invention are conducive to the formation of the pore structure and the loading of the active component nickel.

[0063] According to the preparation method provided by the present invention, in step (1), the mixing method is ball milling mixing, and the ball milling time is 2h-4h. It can be understood that the ball milling time can be any specific value of 2h, 2.2h, 2.4h, 2.6h, 2.8h, 3h, 3.2h, 3.4h, 3.6h, 3.8h, 4h or any value within the range of 2h-4h.

[0064] According to the preparation method provided by the present invention, in step (2), the primary calcination is carried out in a nitrogen and water vapor mixed atmosphere, preferably, the nitrogen and water vapor mixed ratio is N2:H2O=1:(0.4-0.6), more preferably, the nitrogen and water vapor mixed ratio is N2:H2O=1:0.5; the nitrogen and water vapor mixed ratio of the present invention is conducive to the formation of the catalyst pore structure and the stability of the strength; the primary calcination temperature is 1300°C-1550°C, it can be understood that the primary calcination temperature can be 1300°C, 1310°C, 1320°C, 1330°C, 1340°C, 1350°C, 1360°C, 1370°C , 1380℃, 1390℃, 1400℃, 1410℃, 1420℃, 1430℃, 1440℃, 1450℃, 1460℃, 1470℃, 1480℃, 1490℃, 1500℃, 1510℃, 1520℃, 1530℃, 1540℃, 1550℃, or any value in the range of 1300℃-1550℃; the primary roasting time is 4h-8h. It can be understood that the primary roasting time can be any specific value of 4h, 4.5h, 5h, 5.5h, 6h, 6.5h, 7h, 7.5h, 8h, or any value in the range of 4h-8h.

[0065] According to the preparation method provided by the present invention, in step (2), the quenching refers to immediately immersing the calcined carrier in deionized water, preferably, immediately and completely immersing the calcined carrier in deionized water; the temperature of the deionized water is 15°C-150°C, and it can be understood that the temperature of the deionized water can be any specific value among 15°C, 25°C, 35°C, 45°C, 55°C, 65°C, 75°C, 85°C, 95°C, 105°C, 115°C, 125°C, 135°C, 145°C, 150°C, or any value within the range of 15°C-150°C; the quenching time is 10min-30min, and it can be understood that the quenching time can be any specific value among 10min, 12min, 14min, 16min, 18min, 20min, 22min, 24min, 26min, 28min, 30min, or any value within the range of 10min-30min.

[0066] According to the preparation method provided by the present invention, in step (2), the secondary calcination is carried out in a nitrogen atmosphere; the secondary calcination temperature is 1000°C-1350°C. It can be understood that the secondary calcination temperature can be 1000°C, 1010°C, 1020°C, 1030°C, 1040°C, 1050°C, 1060°C, 1070°C, 1080°C, 1090°C, 1100°C, 1110°C, 1120°C, 1130°C, 1140°C, 1150°C, 1160°C, 1170°C, 1180°C, 1190°C, 1200°C, 1210°C, 1220°C, 1230°C, 1240°C, 1250°C Any specific value among 0℃, 1260℃, 1270℃, 1280℃, 1290℃, 1300℃, 1310℃, 1320℃, 1330℃, 1340℃, 1350℃ or any value within the range of 1000℃-1350℃; the secondary roasting time is 10min-30min, it can be understood that the secondary roasting time can be any specific value among 10min, 12min, 14min, 16min, 18min, 20min, 22min, 24min, 26min, 28min, 30min or any value within the range of 10min-30min.

[0067] According to the preparation method provided by the present invention, in step (3), the ultrasonic frequency is 20kHz-60kHz. It can be understood that the ultrasonic frequency can be any specific value of 20kHz, 25kHz, 30kHz, 35kHz, 40kHz, 45kHz, 50kHz, 55kHz, 60kHz or any value within the range of 20kHz-60kHz; the immersion time is 30min-60min. It can be understood that the immersion time can be any specific value of 30min, 35min, 40min, 45min, 50min, 55min, 60min or any value within the range of 30min-60min; the drying is carried out in an oven at a drying temperature of 120℃-180℃. It can be understood that the drying temperature can be 120℃, 125℃, 130℃, 135℃, 140℃, 145℃, 150℃, Any specific value among 155℃, 160℃, 165℃, 170℃, 175℃, 180℃ or any value within the range of 120℃-180℃; the drying time is 8h-24h, and 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, 24h or any value within the range of 8h-24h; the secondary immersion time is 30min-60min, and it can be understood that the secondary immersion time can be any specific value among 30min, 35min, 40min, 45min, 50min, 55min, 60min or any value within the range of 30min-60min. In the present invention, in step (3), when the catalyst carrier is impregnated with the active component, the impregnation is repeated twice under ultrasonic conditions, which can significantly increase the loading amount and dispersion of the active component in the catalyst and improve the activity and stability of the catalyst.

[0068] According to the preparation method provided by the present invention, in step (4), the primary calcination temperature is 350°C-550°C. It can be understood that the primary calcination temperature can be any specific value among 350°C, 360°C, 370°C, 380°C, 390°C, 400°C, 410°C, 420°C, 430°C, 440°C, 450°C, 460°C, 470°C, 480°C, 490°C, 500°C, 510°C, 520°C, 530°C, 540°C, 550°C or any value within the range of 350°C-550°C; the primary calcination time is 2h-8h. It can be understood that the primary calcination time can be 2h, 2.5h, 3h, 3.5h, 4h, 4.5h, 5h, 5. The quenching refers to immersing the calcined catalyst in deionized water immediately, and the temperature of the deionized water is 15°C-150°C. It can be understood that the temperature of the deionized water can be any specific value among 15°C, 25°C, 35°C, 45°C, 55°C, 65°C, 75°C, 85°C, 95°C, 105°C, 115°C, 125°C, 135°C, 145°C, 150°C or any value within the range of 15°C-150°C. The quenching time is 10min-30min. It can be understood that the quenching time can be 10min, 12min, 14mi any specific value among n, 16min, 18min, 20min, 22min, 24min, 26min, 28min, 30min or any value within the range of 10min-30min; the secondary roasting temperature is 1000℃-1350℃, it can be understood that the secondary roasting temperature can be 1000℃, 1010℃, 1020℃, 1030℃, 1040℃, 1050℃, 1060℃, 1070℃, 1080℃, 1090℃, 1100℃, 1110℃, 1120℃, 1130℃, 1140℃, 1150℃, 1160℃, 1170℃, 1180℃, 1190℃, 1200℃, 1210℃ ℃, 1220℃, 1230℃, 1240℃, 1250℃, 1260℃, 1270℃, 1280℃, 1290℃, 1300℃, 1310℃, 1320℃, 1330℃, 1340℃, 1350℃ or any value in the range of 1000℃-1350℃; the secondary roasting time is 10min-30min, it can be understood that the secondary roasting time can be any specific value of 10min, 12min, 14min, 16min, 18min, 20min, 22min, 24min, 26min, 28min, 30min or any value in the range of 10min-30min.

[0069] The inventors of the present invention found in the course of research that according to the preparation method provided by the present invention, firstly, a pre-sintered carrier with rich mesoporous structure and high specific surface area is prepared, and the high specific surface area and high porosity of the carrier are fully utilized to improve the dispersion of active center Ni, increase the number of active centers, and have high stability; a certain amount of catonite is generated while the carrier is prepared, and a large amount of active oxygen in OH- contained in the catonite helps to re-oxidize the C deposited on the catalyst into CO; after the carrier is impregnated with active components, it is quenched again to generate a certain amount of nickel aluminate, and the Ni generated by the reduction of nickel aluminate has a strong interaction with the carrier, and the degree of inhibition of coking and sintering is higher, and it has a higher oxygen surface mobility, which produces a synergistic effect with the catonite, improves the anti-carbon deposition performance of the catalyst, thereby improving the stability of the catalyst and extending its life.

[0070] The present invention also provides the use of the above catalyst or the catalyst prepared by the above preparation method in a hydrocarbon steam reforming process.

[0071] In the present invention, the catalyst is suitable for a hydrocarbon steam reforming process with a reformer inlet temperature of 400°C to 600°C, an outlet temperature of 700°C to 850°C, a reforming carbon space velocity of 600h-1 to 1000h-1, a water-carbon ratio of 2.0 to 4.5, and a pressure of 2.0MPa to 4.0MPa, for producing hydrogen.

[0072] 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 content of the present invention by way of example, and are not intended to limit the present invention.

[0073] The content of each component of the catalyst prepared in the examples and comparative examples was determined by UV-visible diffuse reflectance spectroscopy.

[0074] Example 1 The method for preparing the hydrocarbon steam reforming catalyst described in this embodiment comprises the following steps: Weigh 100g of γ-Al2O3, 130g of calcium aluminate cement, and 30g of calcium carbonate, mix them, then add 5g of graphite and 5g of sesbania powder, ball mill for 3h to fully mix the components, add an appropriate amount of deionized water and press into shape, and calcine at 1450℃ for 6h in an atmosphere of nitrogen and water vapor with a mixing ratio of N2:H2O=1:0.5; immediately immerse the calcined carrier completely in 30℃ deionized water for quenching for 20min until all the carriers are completely cooled; the cooled carrier is re-calculated at 1100℃ in a nitrogen atmosphere for 20min to obtain a catalyst carrier. The carrier was placed in 200 mL of a 200 g / L nickel nitrate solution, immersed under ultrasonic conditions for 40 minutes, filtered and placed in an oven for drying at 150° C. for 12 hours, and then placed in the nickel nitrate solution again for ultrasonic immersion for 40 minutes, filtered and placed in a muffle furnace for calcination and decomposition at 450° C. for 6 hours; the calcined catalyst was immediately and completely immersed in 30° C. deionized water for quenching for 20 minutes until all the catalysts were completely cooled; the quenched catalyst was then placed in a muffle furnace and calcined at 1100 degrees Celsius for 20 minutes, and naturally cooled to room temperature to obtain a hydrocarbon steam reforming catalyst CAT-1.

[0075] After testing, nickel oxide accounts for 17.2wt%, catonite accounts for 8.7wt%, and nickel aluminate accounts for 13.4wt%. The XRD diagram is shown in Figure 1 shown.

[0076] Example 2 The method for preparing the hydrocarbon steam reforming catalyst described in this embodiment comprises the following steps: Weigh 100g of γ-Al2O3, 120g of calcium aluminate cement, and 20g of calcium carbonate, and then add 3g of graphite and 2g of sesbania powder, ball mill for 2h to fully mix the components, add an appropriate amount of deionized water and press into shape, and the subsequent steps are the same as in Example 1 to obtain hydrocarbon steam reforming catalyst CAT-2.

[0077] After testing, nickel oxide accounts for 16.1wt%, catonite accounts for 7.6wt%, and nickel aluminate accounts for 11.9wt%.

[0078] Example 3 The method for preparing the hydrocarbon steam reforming catalyst described in this embodiment comprises the following steps: Weigh 100g of γ-Al2O3, 140g of calcium aluminate cement, and 40g of calcium carbonate, and then add 8g of graphite and 7g of sesbania powder, ball mill for 4h to fully mix the components, add an appropriate amount of deionized water and press into shape, and the subsequent steps are the same as in Example 1. A hydrocarbon steam reforming catalyst CAT-3 is obtained.

[0079] After testing, nickel oxide accounts for 15.8wt%, catonite accounts for 9.2wt%, and nickel aluminate accounts for 12.7wt%.

[0080] Example 4 The method for preparing the hydrocarbon steam reforming catalyst described in this embodiment comprises the following steps: Weigh 100g of γ-Al2O3, 130g of calcium aluminate cement, and 30g of calcium carbonate, and then add 5g of graphite and 5g of sesbania powder. Ball mill for 3h to fully mix the components, add an appropriate amount of deionized water and then press into shape. In an atmosphere of nitrogen and water vapor with a mixing ratio of N2:H2O=1:0.4, calcine at 1300℃ for 4h; immediately immerse the calcined carrier completely in 30℃ deionized water for quenching for 20min until all the carriers are completely cooled; the cooled carrier is re-calculated at 1000℃ in a nitrogen atmosphere for 20min to obtain a catalyst carrier, and the subsequent steps are the same as in Example 1 to obtain a hydrocarbon steam reforming catalyst CAT-4.

[0081] After testing, nickel oxide accounts for 12.3wt%, catecholite accounts for 7.3wt%, and nickel aluminate accounts for 13.2wt%.

[0082] Example 5 The method for preparing the hydrocarbon steam reforming catalyst described in this embodiment comprises the following steps: Weigh 100g of γ-Al2O3, 130g of calcium aluminate cement, and 30g of calcium carbonate, and then add 5g of graphite and 5g of sesbania powder. Ball mill for 3h to fully mix the components, add an appropriate amount of deionized water and then press into shape. In an atmosphere of nitrogen and water vapor with a mixing ratio of N2:H2O=1:0.6, calcine at 1550°C for 4h; immediately immerse the calcined carrier completely in 30°C deionized water for quenching for 20min until all the carriers are completely cooled; the cooled carrier is re-calculated at 1350°C in a nitrogen atmosphere for 20min to obtain a catalyst carrier, and the subsequent steps are the same as in Example 1 to obtain a hydrocarbon steam reforming catalyst CAT-5.

[0083] After testing, nickel oxide accounts for 15.3wt%, catonite accounts for 6.9wt%, and nickel aluminate accounts for 10wt%.

[0084] Example 6 The method for preparing the hydrocarbon steam reforming catalyst described in this embodiment comprises the following steps: Weigh 100g of γ-Al2O3, 130g of calcium aluminate cement, and 30g of calcium carbonate, mix them, then add 5g of graphite and 5g of sesbania powder, ball mill for 3h to fully mix the components, add an appropriate amount of deionized water and press into shape, and calcine at 1450℃ for 6h in an atmosphere of nitrogen and water vapor with a mixing ratio of N2:H2O=1:0.5; immediately immerse the calcined carrier completely in 15℃ deionized water for quenching for 30min until all the carriers are completely cooled; the cooled carrier is re-calculated at 1100℃ in a nitrogen atmosphere for 20min to obtain a catalyst carrier. The nickel nitrate impregnation steps are the same as those in Example 1; after the second impregnation, the catalyst is filtered and dried, and placed in a muffle furnace for calcination and decomposition at 450°C for 6 hours; the calcined catalyst is immediately and completely immersed in 15°C deionized water for quenching for 30 minutes until all the catalysts are completely cooled; the quenched catalyst is then placed in a muffle furnace and calcined at 1100°C for 20 minutes, and naturally cooled to room temperature to obtain a hydrocarbon steam reforming catalyst CAT-6.

[0085] After testing, nickel oxide accounts for 13.9wt%, catecholite accounts for 9.1wt%, and nickel aluminate accounts for 12.9wt%.

[0086] Example 7 The method for preparing the hydrocarbon steam reforming catalyst described in this embodiment comprises the following steps: Weigh 100g of γ-Al2O3, 130g of calcium aluminate cement, and 30g of calcium carbonate, mix them, then add 5g of graphite and 5g of sesbania powder, ball mill for 3h to fully mix the components, add an appropriate amount of deionized water and then press into shape, and calcine at 1450℃ for 6h in an atmosphere of nitrogen and water vapor with a mixing ratio of N2:H2O=1:0.5; immediately immerse the calcined carrier completely in 150℃ deionized water for quenching for 10min, until all the carriers are completely cooled; the cooled carrier is re-calcined at 1100℃ in a nitrogen atmosphere for 20min to obtain a catalyst carrier. The nickel nitrate impregnation steps are the same as those in Example 1; after the second impregnation, the catalyst is filtered and dried, and placed in a muffle furnace for calcination and decomposition at 450°C for 6 hours; the calcined catalyst is immediately and completely immersed in 150°C deionized water for quenching for 10 minutes until all the catalysts are completely cooled; the quenched catalyst is then placed in a muffle furnace and calcined at 1100°C for 20 minutes, and naturally cooled to room temperature to obtain a hydrocarbon steam reforming catalyst CAT-7.

[0087] After testing, nickel oxide accounts for 11.2wt%, catonite accounts for 6.4wt%, and nickel aluminate accounts for 11.4wt%.

[0088] Example 8 The method for preparing the hydrocarbon steam reforming catalyst described in this embodiment comprises the following steps: The steps for preparing the carrier are the same as those in Example 1. The carrier is placed in 200 mL of a 200 g / L nickel nitrate solution, immersed under ultrasonic conditions for 30 min, filtered and placed in an oven for drying at 120° C. for 8 h, then placed in the nickel nitrate solution again for ultrasonic immersion for 30 min, filtered and placed in a muffle furnace for calcination and decomposition at 350° C. for 2 h; the calcined catalyst is immediately and completely immersed in 30° C. deionized water for quenching for 20 min until all the catalysts are completely cooled; then the quenched catalyst is placed in a muffle furnace for calcination at 1000° C. for 10 min, and naturally cooled to room temperature to obtain a hydrocarbon steam reforming catalyst CAT-8.

[0089] After testing, nickel oxide accounts for 10.2wt%, catecholite accounts for 5.7wt%, and nickel aluminate accounts for 11.1wt%.

[0090] Example 9 The method for preparing the hydrocarbon steam reforming catalyst described in this embodiment comprises the following steps: The steps for preparing the carrier are the same as those in Example 1. The carrier is placed in 200 mL of a 200 g / L nickel nitrate solution, immersed under ultrasonic conditions for 60 min, filtered and placed in an oven at 180° C. for drying for 24 h, then placed in the nickel nitrate solution again for ultrasonic immersion for 60 min, filtered and placed in a muffle furnace for calcination and decomposition at 550° C. for 8 h; the calcined catalyst is immediately and completely immersed in 30° C. deionized water for quenching for 20 min until all the catalysts are completely cooled; the quenched catalyst is then placed in a muffle furnace and calcined at 1350° C. for 30 min, and naturally cooled to room temperature to obtain a hydrocarbon steam reforming catalyst CAT-9.

[0091] After testing, nickel oxide accounts for 15.4wt%, catonite accounts for 8.5wt%, and nickel aluminate accounts for 13.6wt%.

[0092] Comparative Example 1 The preparation method of the hydrocarbon steam reforming catalyst described in this comparative example comprises the following steps: Weigh 100g of γ-Al2O3, 130g of calcium aluminate cement, and 30g of calcium carbonate, then add 5g of graphite and 5g of sesbania powder, ball mill for 3h to fully mix the components, add an appropriate amount of deionized water and press into shape, and calcine at 1450℃ for 6h in an atmosphere of nitrogen and water vapor with a mixing ratio of N2:H2O=1:0.5 to obtain a catalyst carrier. Put the carrier into 200mL of 200g / L nickel nitrate solution, immerse it under ultrasonic conditions for 40min, filter it dry, put it in an oven at 150℃ for drying for 12h, then put it into the nickel nitrate solution again for ultrasonic immersion for 40min, filter it dry, put it in a muffle furnace at 450℃ for calcination and decomposition for 6h to obtain hydrocarbon steam reforming catalyst D-CAT-1.

[0093] After testing, nickel oxide accounts for 16.3wt%, there is no catorite component, and nickel aluminate accounts for 8.9wt%.

[0094] Comparative Example 2 The preparation method of the hydrocarbon steam reforming catalyst described in this comparative example comprises the following steps: Weigh 100g of γ-Al2O3, 130g of calcium aluminate cement, and 30g of calcium carbonate, mix them, then add 5g of graphite and 5g of sesbania powder, ball mill for 3h to fully mix the components, add an appropriate amount of deionized water and press into shape, and calcine at 1450℃ for 6h in an atmosphere of nitrogen and water vapor mixed in a ratio of N2:H2O=1:0.5 to obtain a catalyst carrier. The carrier was placed in 200 mL of a 200 g / L nickel nitrate solution, immersed under ultrasonic conditions for 40 minutes, filtered and placed in an oven for drying at 150° C. for 12 hours, and then placed in the nickel nitrate solution again for ultrasonic immersion for 40 minutes, filtered and placed in a muffle furnace for calcination and decomposition at 450° C. for 6 hours; the calcined catalyst was immediately and completely immersed in 30° C. deionized water for quenching for 20 minutes until all the catalysts were completely cooled; the quenched catalyst was then placed in a muffle furnace and calcined at 1100 degrees Celsius for 20 minutes, and naturally cooled to room temperature to obtain a hydrocarbon steam reforming catalyst D-CAT-2.

[0095] After testing, nickel oxide accounts for 14.8wt%, catonite accounts for 2.5wt%, and nickel aluminate accounts for 9.2wt%.

[0096] Comparative Example 3 The preparation method of the hydrocarbon steam reforming catalyst described in this comparative example comprises the following steps: Weigh 100g of γ-Al2O3, 130g of calcium aluminate cement, and 30g of calcium carbonate, mix them, then add 5g of graphite and 5g of sesbania powder, ball mill for 3h to fully mix the components, add an appropriate amount of deionized water and press into shape, and calcine at 1450℃ for 6h in an atmosphere of nitrogen and water vapor with a mixing ratio of N2:H2O=1:0.5; immediately immerse the calcined carrier completely in 30℃ deionized water for quenching for 20min, until all the carriers are completely cooled, and put them into an oven for drying at 120℃ for 12h to obtain a catalyst carrier. The carrier was placed in 200 mL of a 200 g / L nickel nitrate solution, immersed under ultrasonic conditions for 40 minutes, filtered and dried in an oven at 150° C. for 12 hours, then placed in the nickel nitrate solution again for ultrasonic immersion for 40 minutes, filtered and dried, and placed in a muffle furnace for calcination and decomposition at 450° C. for 6 hours; the calcined catalyst was immediately and completely immersed in deionized water at 30° C. for quenching for 20 minutes, and placed in an oven at 120° C. for drying for 12 hours to obtain a hydrocarbon steam reforming catalyst D-CAT-3.

[0097] After testing, nickel oxide accounts for 15.2wt%, catonite accounts for 0.6wt%, and nickel aluminate accounts for 1.7wt%.

[0098] Comparative Example 4 The preparation method of the hydrocarbon steam reforming catalyst described in this comparative example comprises the following steps: Weigh 100g of γ-Al2O3, 125g of calcium aluminate cement, and 25g of calcium carbonate, then add 5g of graphite and 3g of sesbania powder, ball mill for 3h to fully mix the components, add an appropriate amount of deionized water and press into shape, and calcine at 1450℃ for 6h in an atmosphere of nitrogen and water vapor with a mixing ratio of N2:H2O=1:0.5; immediately immerse the calcined carrier completely in 30℃ deionized water for quenching for 20min, until all the carriers are completely cooled, and then put them in an oven at 120℃ for drying for 12h to obtain a catalyst carrier. The subsequent steps are the same as in Example 1 to obtain hydrocarbon steam reforming catalyst D-CAT-4.

[0099] After testing, nickel oxide accounts for 14.5wt%, catonite accounts for 1.6wt%, and nickel aluminate accounts for 10.3wt%.

[0100] Comparative Example 5 The preparation method of the hydrocarbon steam reforming catalyst described in this comparative example comprises the following steps: The steps for preparing the carrier are the same as those in Example 1. The carrier is placed in 200 mL of a 200 g / L nickel nitrate solution, immersed under ultrasonic conditions for 40 min, filtered, and placed in an oven at 150° C. for drying for 12 h, then placed in the nickel nitrate solution again for ultrasonic immersion for 40 min, filtered, and placed in a muffle furnace for calcination and decomposition at 450° C. for 6 h; the calcined catalyst is immediately and completely immersed in deionized water at 30° C. for quenching for 20 min, placed in an oven at 120° C. for drying for 12 h, and a hydrocarbon steam reforming catalyst D-CAT-5 is obtained.

[0101] After testing, nickel oxide accounts for 13.9wt%, catonite accounts for 4.2wt%, and nickel aluminate accounts for 6.6wt%.

[0102] Comparative Example 6 The preparation method of the hydrocarbon steam reforming catalyst described in this comparative example comprises the following steps: Weigh 100g of γ-Al2O3, 130g of calcium aluminate cement, and 30g of calcium carbonate, then add 5g of graphite and 5g of sesbania powder, ball mill for 3h to fully mix the components, add an appropriate amount of deionized water and press into shape, and calcine at 1450℃ in a muffle furnace for 6h; immediately immerse the calcined carrier in 30℃ deionized water for quenching for 20min until all the carriers are completely cooled; calcine the cooled carrier again at 1100℃ in a nitrogen atmosphere for 20min to obtain a catalyst carrier. The subsequent steps are the same as in Example 1 to obtain hydrocarbon steam reforming catalyst D-CAT-6.

[0103] After testing, nickel oxide accounts for 8.7wt%, catonite accounts for 2.4wt%, and nickel aluminate accounts for 11.5wt%.

[0104] Comparative Example 7 The preparation method of the hydrocarbon steam reforming catalyst described in this comparative example comprises the following steps: The steps for preparing the carrier are the same as those in Example 1. The carrier is immersed in 200 mL of a 200 g / L nickel nitrate solution for 40 min, filtered and dried in an oven at 150° C. for 12 h, then immersed in a nickel nitrate solution for 40 min again, filtered and dried, placed in a muffle furnace for calcination and decomposition at 450° C. for 6 h, and the calcined catalyst is immediately and completely immersed in 30° C. deionized water for quenching for 20 min until all the catalysts are completely cooled; then the quenched catalyst is placed in a muffle furnace and calcined at 1100 degrees Celsius for 20 min, and naturally cooled to room temperature to obtain a hydrocarbon steam reforming catalyst D-CAT-7.

[0105] After testing, nickel oxide accounts for 13.9wt%, catecholite accounts for 6.2wt%, and nickel aluminate accounts for 6.6wt%.

[0106] Comparative Example 8 The preparation method of the hydrocarbon steam reforming catalyst described in this comparative example comprises the following steps: Weigh 100g of γ-Al2O3, 130g of calcium aluminate cement, and 30g of calcium carbonate, then add 5g of graphite and 5g of sesbania powder, ball mill for 3h to fully mix the components, add an appropriate amount of deionized water and press into shape, and calcine at 800℃ for 6h in an atmosphere of nitrogen and water vapor with a mixing ratio of N2:H2O=1:0.5; immediately immerse the calcined carrier in 30℃ deionized water for quenching for 20min until all the carriers are completely cooled; calcine the cooled carrier again at 800℃ in a nitrogen atmosphere for 20min to obtain a catalyst carrier. The subsequent steps are the same as in Example 1 to obtain hydrocarbon steam reforming catalyst D-CAT-8.

[0107] After testing, nickel oxide accounts for 11.2wt%, catonite accounts for 4.1wt%, and nickel aluminate accounts for 11.3wt%.

[0108] Comparative Example 9 The preparation method of the hydrocarbon steam reforming catalyst described in this comparative example comprises the following steps: The steps for preparing the carrier are the same as those in Example 1. The carrier is placed in 200 mL of a 200 g / L nickel nitrate solution and immersed under ultrasonic conditions for 40 min, then filtered and dried, placed in a muffle furnace for calcination and decomposition at 450° C. for 6 h, and placed in a muffle furnace for calcination and decomposition at 450° C. for 6 h; the calcined catalyst is immediately and completely immersed in 30° C. deionized water for quenching for 20 min until all the catalysts are completely cooled; then the quenched catalyst is placed in a muffle furnace for calcination at 1100 degrees Celsius for 20 min, and naturally cooled to room temperature to obtain a hydrocarbon steam reforming catalyst D-CAT-9.

[0109] After testing, nickel oxide accounts for 6.2wt%, catecholite accounts for 6.9wt%, and nickel aluminate accounts for 6.8wt%.

[0110] Comparative Example 10 The preparation method of the hydrocarbon steam reforming catalyst described in this comparative example comprises the following steps: Weigh 100g of γ-Al2O3 and calcium carbonate, add an appropriate amount of deionized water and press into shape, and calcine at 1450℃ for 6h in an atmosphere of nitrogen and water vapor with a mixing ratio of N2:H2O=1:0.5; immediately immerse the calcined carrier in 30℃ deionized water for quenching for 20min until all the carriers are completely cooled; calcine the cooled carrier again at 1100℃ in a nitrogen atmosphere for 20min to obtain a catalyst carrier. The subsequent steps are the same as in Example 1 to obtain hydrocarbon steam reforming catalyst D-CAT-10.

[0111] After testing, nickel oxide accounts for 9.4wt%, catonite accounts for 3.7wt%, and nickel aluminate accounts for 7.9wt%.

[0112] Comparative Example 11 The preparation method of the hydrocarbon steam reforming catalyst described in this comparative example comprises the following steps: Weigh 100g of γ-Al2O3, 50g of calcium aluminate cement, and 10g of calcium carbonate, then add 2g of graphite and 2g of sesbania powder, ball mill for 3h to fully mix the components, add an appropriate amount of deionized water and press into shape, and calcine at 1450℃ for 6h in an atmosphere of nitrogen and water vapor with a mixing ratio of N2:H2O=1:0.5; immediately immerse the calcined carrier in 30℃ deionized water for quenching for 20min until all the carriers are completely cooled; calcine the cooled carrier again at 1100℃ in a nitrogen atmosphere for 20min to obtain a catalyst carrier. The subsequent steps are the same as in Example 1 to obtain hydrocarbon steam reforming catalyst D-CAT-11.

[0113] After testing, nickel oxide accounts for 7.5wt%, catonite accounts for 4.2wt%, and nickel aluminate accounts for 8.8wt%.

[0114] Comparative Example 12 The preparation method of the hydrocarbon steam reforming catalyst described in this comparative example comprises the following steps: Weigh 100g of γ-Al2O3, 200g of calcium aluminate cement, and 50g of calcium carbonate, then add 10g of graphite and 10g of sesbania powder, ball mill for 3h to fully mix the components, add an appropriate amount of deionized water and press into shape, and calcine at 1450℃ for 6h in an atmosphere of nitrogen and water vapor with a mixing ratio of N2:H2O=1:0.5; immediately immerse the calcined carrier in 30℃ deionized water for quenching for 20min until all the carriers are completely cooled; calcine the cooled carrier again at 1100℃ in a nitrogen atmosphere for 20min to obtain a catalyst carrier. The subsequent steps are the same as in Example 1 to obtain hydrocarbon steam reforming catalyst D-CAT-12.

[0115] After testing, nickel oxide accounts for 5.8wt%, catecholite accounts for 2.1wt%, and nickel aluminate accounts for 6.4wt%.

[0116] Comparative Example 13 Take the industrial catalyst D-CAT-13. The proportion of nickel oxide in the catalyst is ≥16wt%, there is no catorite component, and the proportion of nickel aluminate is about 2.8wt%.

[0117] Experimental example The present invention uses a fixed bed reactor of a micro atmospheric pressure evaluation device for evaluating catalyst activity, uses methane as a raw material, and selects methane conversion rate as a reference index of catalyst activity. The specific flow diagram of the fixed bed reactor of the micro atmospheric pressure evaluation device is shown in the attached Figure 2 .

[0118] The specific steps of evaluating the catalyst activity using a fixed bed reactor of a micro atmospheric pressure evaluation device are as follows: The catalyst was filled into the fixed bed reactor of the micro atmospheric pressure evaluation device. The catalyst particle size was 40-60 mesh particles, the loading amount was 0.2g (0.2mL, the inner diameter of the reaction tube was 6mm), and the filling bed height was 9mm. First, the catalyst sample was reduced at 850℃ in H2 atmosphere for 2h. After the reduction was completed, the temperature in the reactor was lowered to the reaction temperature of 750℃. At a carbon space velocity of 20000h -1 The catalytic performance of the catalyst was evaluated under the conditions of , water-carbon ratio of 4, and water-hydrogen ratio <7.5. During the reaction, the flow of H2 and CH4 was controlled by a mass flow meter, and the water feed amount was controlled by a pump. H2, CH4 and water were first heated in a preheater and then mixed evenly in a mixer before entering the reactor. The preheater and reactor were both heated by electric furnace wires, and K-type thermocouples were installed on the inner wall. The preheating and reaction temperatures were measured and controlled by a temperature controller. After the system was stable, an Agilent 8860 gas chromatograph was used to analyze the reaction tail gas online.

[0119] The conversion rate (X) of methane was calculated by the following formula. The specific results are shown in Table 1.

[0120] .

[0121] Where: It is the percentage (%) of each component in the conversion gas analyzed by chromatography.

[0122] The specific determination method of the specific surface area, pore volume and pore diameter of the hydrocarbon steam reforming catalyst of the present invention is as follows: weigh about 0.1 g of the sample, degas for 6 h at 200°C, and then test it in a liquid nitrogen environment at -196°C using nitrogen as an adsorbent, and calculate the properties and specific surface area of ​​the catalyst pores using the Barrett-Joyner-Halenda (BJH) method for the adsorption-desorption curve. The specific results are shown in Table 1.

[0123] The present invention uses X-ray diffraction (XRD) to determine the grain size of the active component of the hydrocarbon steam reforming catalyst. The specific determination method is as follows: before the test, the sample is pressed into a thin sheet, and a Smart-lab3 diffractometer of Rigaku Corporation is used, using a Cu-Kɑ target line, an incident wavelength of 1.54056Å, a scanning range of 0°-90°, and a scanning speed of 10° / min. The NiO grain size of the series of catalysts is calculated by the Scherrer equation, and the specific results are shown in Table 1.

[0124] The method for measuring the lateral compressive strength of the present invention is as follows: The formed catalyst particles are placed on the sample platform of the strength tester according to the hole-oriented position, and pressure is applied to the catalyst evenly and gradually until it breaks, and the catalyst lateral compression strength is measured.

[0125] The content of nickel oxide and other components in the hydrocarbon steam reforming catalyst of the present invention is determined by a ZSX Primus II type X-ray fluorescence spectrometer (XRF).

[0126] The carbon content in the catalyst unloading sample of the present invention is measured by a HIR-944C infrared carbon-sulfur analyzer and a matching SK2 high-pressure tubular combustion furnace.

[0127] The carbon content in the catalyst unloading sample of the present invention is determined by a carbon-sulfur analyzer.

[0128] Table 1 Physical and chemical properties of catalysts in examples and comparative examples .

[0129] It can be seen from the data in Table 1 that the calcination-quenching-calcination process after the catalyst carrier is formed is a key step in generating the catonite component, and the calcination-quenching-calcination process of the catalyst after impregnation is a key step in generating the nickel aluminate component, and the two quenchings play a key role in providing the catalyst with suitable strength, pore structure and specific surface area. Compared with the comparative example, the catalyst prepared by the method described in the embodiment of the present invention contains rich catonite components and nickel aluminate components at the same time. The synergistic effect of the two makes the catalyst have excellent anti-coking performance, high lateral pressure strength, large specific surface area and pore volume, and excellent methane conversion rate. The comprehensive performance of the catalyst prepared by the present invention is higher than that of the catalyst in the comparative example, and the dispersion of the active component NiO is good, and the grain size is well controlled.

[0130] 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 protection scope of the present invention.

Claims

1. A hydrocarbon steam reforming catalyst, characterized in that: The catalyst, calculated on a total basis, comprises the following components by weight: Nickel oxide active component 8wt%-20wt%; Catonite 5wt%-10wt%; Nickel aluminate 10wt%-15wt%; ɑ-Al2O3 35wt%-45wt%; CaO 15wt%-25wt%.

2. The hydrocarbon steam reforming catalyst according to claim 1, characterized in that: The catalyst has one or more of the following characteristics: pore volume ≥ 0.15 mL / g, bulk density 0.80 kg / L-1.20 kg / L, specific surface area ≥ 60 m 2 / g, lateral compression strength is greater than 300N / grain.

3. The hydrocarbon steam reforming catalyst according to claim 1, characterized in that: The catalyst is in the shape of a porous sphere or column; the catalyst is in the shape of a Raschig ring, a four-hole cylinder, a seven-hole cylinder, or a seven-rib wheel.

4. A method for preparing the hydrocarbon steam reforming catalyst according to any one of claims 1 to 3, characterized in that: The steps include: Take γ-Al2O3, calcium aluminate cement, and calcium carbonate according to their mass content, add a binder and a pore-enlarging agent, mix them thoroughly, and press them into shape to obtain a carrier to be calcined; The carrier to be calcined obtained in step (1) is calcined once, the calcined carrier is immersed in deionized water at a specific temperature for quenching, the quenched carrier is calcined twice, and cooled to obtain a cooled carrier; The cooled carrier obtained in step (2) is placed in a nickel nitrate solution and impregnated once under ultrasonic conditions. The impregnated catalyst is dried and then placed in the nickel nitrate solution again and impregnated twice under ultrasonic conditions; The catalyst obtained in step (3) after the secondary impregnation is placed in a muffle furnace for primary calcination, and the calcined catalyst is immersed in deionized water at a specific temperature for quenching, and the quenched catalyst is secondary calcined and naturally cooled to room temperature to obtain the hydrocarbon steam reforming catalyst.

5. The method for preparing a hydrocarbon steam reforming catalyst according to claim 4, characterized in that: In step (1), the calcium aluminate cement is pure calcium aluminate cement; in terms of weight percentage, the calcium aluminate cement comprises 72%-82% Al2O3 and 18%-23% CaO.

6. The method for preparing a hydrocarbon steam reforming catalyst according to claim 4, characterized in that: In step (1), the weight ratio of γ-Al2O3, calcium aluminate cement and calcium carbonate is γ-Al2O3: calcium aluminate cement: calcium carbonate = 1: (1.2-1.4): (0.2-0.4).

7. The method for preparing a hydrocarbon steam reforming catalyst according to claim 4, characterized in that: In step (1), the binder is selected from graphite binders; and / or the pore-forming agent is selected from one or more of carbon powder, nitrates, and carbonates.

8. The method for preparing a hydrocarbon steam reforming catalyst according to claim 4, characterized in that: In step (1), the mixing method is ball milling, and the ball milling time is 2h-4h.

9. The method for preparing a hydrocarbon steam reforming catalyst according to claim 4, characterized in that: In step (2), the primary calcination is carried out in a nitrogen and water vapor mixed atmosphere, the nitrogen and water vapor mixing ratio is N2:H2O=1:(0.4-0.6); the primary calcination temperature is 1300°C-1550°C, and the primary calcination time is 4h-8h.

10. The method for preparing a hydrocarbon steam reforming catalyst according to claim 4, characterized in that: In step (2), the quenching refers to immediately immersing the calcined carrier in deionized water, the temperature of the deionized water is 15°C-150°C, and the quenching time is 10min-30min.

11. The method for preparing a hydrocarbon steam reforming catalyst according to claim 4, characterized in that: In step (2), the secondary calcination is carried out in a nitrogen atmosphere, the secondary calcination temperature is 1000°C-1350°C, and the secondary calcination time is 10min-30min.

12. The method for preparing a hydrocarbon steam reforming catalyst according to claim 4, characterized in that The method has one or more of the following features: In step (3), the frequency of the ultrasound is 20kHz-60kHz; In step (3), the immersion time is 30 min to 60 min; In step (3), the drying temperature is 120°C-180°C, and the drying time is 8h-24h; In step (3), the secondary immersion time is 30 min-60 min.

13. The method for preparing a hydrocarbon steam reforming catalyst according to claim 4, characterized in that The method has one or more of the following features: In step (4), the primary calcination temperature is 350°C-550°C, and the primary calcination time is 2h-8h; In step (4), the quenching refers to immediately immersing the calcined catalyst in deionized water, the temperature of the deionized water is 15°C-150°C, and the quenching time is 10min-30min; In step (4), the secondary calcination temperature is 1000°C-1350°C, and the secondary calcination time is 10min-30min.

14. Use of the catalyst according to any one of claims 1 to 3 or the catalyst prepared by the preparation method according to any one of claims 4 to 13 in a hydrocarbon steam reforming process.

15. The use according to claim 14, characterized in that: The catalyst is suitable for a converter with an inlet temperature of 400°C-600°C, an outlet temperature of 700°C-850°C, and a conversion carbon space velocity of 600h -1 -1000h -1 , a hydrocarbon steam reforming process with a water-to-carbon ratio of 2.0-4.5 and a pressure of 2.0MPa-4.0MPa, is used to produce hydrogen.

Images