Hydrocarbon steam reforming catalyst and preparation method thereof

Abstract

The invention discloses a hydrocarbon steam conversion catalyst and a preparation method thereof. The catalyst comprises NiO, ZrO, K2O, Al2O3, CaO and MgO. The carrier disclosed by the invention mainly adopts a magnesium aluminate spinel structure which is prepared by high-pressure crystallization and is uniform in grain size, and the high-temperature stable calcium-potassium aluminate auxiliary agent and zirconium dioxide are added, so that the catalyst carrier has obvious alkalinity and alkaline stability and an obvious anti-carbon deposition effect, and the potassium release rate in the high-temperature synthesized calcium-potassium aluminate auxiliary agent is low; system scaling caused by rapid loss of potassium and alkali can be effectively prevented, so that long-period stable operation of the whole conversion section is facilitated; in addition, by adding the two structural assistants, the active component nickel can be effectively dispersed, so that the catalyst has higher nickel dispersity, nickel grain size growth caused by high-temperature thermal aging in the operation process of the catalyst can be effectively resisted, and the activity stability of the catalyst is improved.

Description

Technical Field

[0001] The present application relates to the technical field of industrial catalysts, and in particular to hydrocarbon steam reforming catalysts and preparation methods thereof. Background Art

[0002] In the past two years, China has seen rapid growth in the production of syngas from biomass and the conversion of waste oils and fats to biomass energy. Both processes involve the conversion and utilization of hydrogen. The hydrogen feedstocks used for biomass feedstocks and oil hydrogenation differ from traditional natural gas (primarily methane) in that they have a more complex composition, with a higher concentration of hydrocarbons, particularly higher hydrocarbons, including various alkanes and cycloalkanes.

[0003] Due to the complex composition of higher hydrocarbons, thermal cracking of higher hydrocarbons during the reaction process easily leads to carbon deposition. The reactions that form carbon may also include:

[0004] 2CO=C+CO2

[0005] CO+H2=C+H2O

[0006] CH4=C+2H2.

[0007] The above-mentioned carbon deposits on the catalyst will block the pores and surface of the catalyst, easily causing the catalyst to break and quickly deactivate, greatly shortening the service life of the hydrocarbon steam reforming catalyst.

[0008] In the related art, the methods adopted to solve the carbon resistance problem of conversion catalysts include: first, to improve the low-temperature activity of the catalyst as much as possible, and at the same time use an alkaline carrier to increase the water-carbon ratio during the reaction. Under specific conditions, this method can temporarily alleviate the carbon precipitation effect of the conversion process, but it significantly increases the energy consumption of the system, which is economically unreasonable; second, adding potassium salts (directly adding various potassium salts, adding potassium nephrite), relying on potassium to promote the vaporization reaction of carbon. The addition of direct potassium salts can improve the carbon resistance of the catalyst, but the addition of direct potassium salts has the disadvantage that potassium is easily lost, and the loss of potassium will reduce the activity and stability of the catalyst to a certain extent; in addition, the loss of potassium and the loss of silica in potassium nephrite at high temperature will also easily cause scaling of the subsequent waste boiler system and reduce the heat exchange efficiency. Summary of the Invention

[0009] In view of this, the present application provides a hydrocarbon steam reforming catalyst and a preparation method thereof, aiming to solve the problem that the existing hydrocarbon steam reforming catalyst operates under low water-carbon ratio conditions with high-carbon hydrocarbons as raw materials, and the catalyst has anti-coking performance. At the same time, it causes scaling of the subsequent waste boiler system and increases the energy consumption of the system due to the rapid loss of potassium in the catalyst.

[0010] The embodiment of the present application is implemented as follows:

[0011] In a first aspect, the present invention provides a hydrocarbon steam reforming catalyst comprising NiO, ZrO, K2O, Al2O3, CaO, and MgO.

[0012] In some embodiments, the catalyst comprises, by mass percentage, 10% to 15% NiO, 0.5% to 1% ZrO, 1% to 2% K2O, 60% to 75% Al2O3, 3% to 6% CaO, and 10% to 25% MgO.

[0013] In a second aspect, the present invention provides a method for preparing a hydrocarbon steam reforming catalyst, comprising:

[0014] Provide MgAl2O4 spinel powder;

[0015] Provide potassium calcium aluminate powder;

[0016] MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconium oxide, graphite, and short fibers are ball-milled, granulated with water, pressed, and calcined to obtain a catalyst carrier;

[0017] The catalyst carrier is impregnated in a nickel nitrate solution, dried and then calcined to obtain a finished catalyst product.

[0018] In some embodiments, the method for preparing MgAl2O4 spinel powder includes:

[0019] Take a sodium aluminate solution with an alumina mass concentration of C1, dilute it with water to an alumina mass concentration of C2, and heat it to T1 for later use;

[0020] According to the mass ratio of MgO:HNO3 of m1:m2, magnesium oxide is added to the desalted water of a% of the volume of the reactor, and then nitric acid with a mass concentration of C3 is added dropwise and mixed evenly. After grinding, the mixture is first sieved, and finally water is added to prepare the MgO concentration to C4, and the temperature is raised to T2 for standby use;

[0021] Add desalted water with a volume of C5 into the autoclave, raise the temperature to T3, and set aside;

[0022] The above-mentioned sodium metaaluminate solution and magnesium oxide slurry are added to the high temperature and high pressure reactor at the same time. The stirring speed of the reactor during the neutralization process is v, the addition time is t1, the pH value of the whole process is t4, and the reaction temperature is T4;

[0023] After the neutralization reaction is completed, the autoclave is pressurized to P1, the reaction is continued for t2, and then the pressure is reduced to normal pressure. The material is filtered and washed in a filter until the Na2O content is lower than C6;

[0024] The washed filter cake is dried under conditions T5 for t3, then calcined under conditions T6 for t4, and the calcined material is ball-milled until the second sieving is performed to obtain MgAl2O4 spinel powder; and / or

[0025] The preparation method of potassium calcium aluminate powder comprises:

[0026] Based on the Al2O3 content in aluminum hydroxide, add CaO powder with a weight content of C7, ball mill and mix together, ball mill to the third sieve, and set aside;

[0027] Based on the Al2O3 content in aluminum hydroxide, weigh the KOH solid with a weight content of C8, and add deionized water with a weight M of the weighed KOH solid to dissolve it and set aside;

[0028] Add the spare aluminum hydroxide containing CaO into the mixer, mix the dry powder for t5, add the above-mentioned spare KOH solution and mix for t6; the mixed wet material is extruded into strips with a width of X1 and a length of X2, and naturally dried for t7, and then heated to T7 in a muffle furnace and calcined for t8, and then pulverized to the fourth sieve after cooling to obtain potassium calcium aluminate powder with a structure of KCa 1 / 2 Al2O4.

[0029] In some embodiments, C1 is 30% to 37%; and / or

[0030] C2 is 90g / L to 120g / L; and / or

[0031] T1 is 60°C to 70°C; and / or

[0032] m1:m2 is 100:5-7; and / or

[0033] C3 is 15% to 20%; and / or

[0034] C4 is 30g / L to 50g / L; and / or

[0035] T2 is 60°C to 70°C; and / or

[0036] a% is 10% to 15%; and / or

[0037] The first sieve has a mesh size of 300; and / or

[0038] C5 is 10% to 20%; and / or

[0039] T3 is 60°C to 70°C; and / or

[0040] v is 300 rpm to 500 rpm; and / or

[0041] t1 is 90 min to 120 min; and / or

[0042] pH 7-8; and / or

[0043] T4 is 60°C to 70°C; and / or

[0044] P1 is 8MPa to 10MPa; and / or

[0045] t2 is 12h to 18h; and / or

[0046] C6 is 0.05%; and / or

[0047] T5 is 80°C to 120°C; and / or

[0048] t3 is 8h to 20h; and / or

[0049] T6 is 1180°C to 1230°C; and / or

[0050] t4 is 3h to 5h; and / or

[0051] The mesh size of the second sieve is 100-150 mesh; and / or

[0052] C7 is 25% to 30%; and / or

[0053] The mesh size of the third sieve is 250-320 mesh; and / or

[0054] C8 is 40% to 60%; and / or

[0055] M is 2.1 to 2.5 times; and / or

[0056] t5 is 30 to 60 minutes; and / or

[0057] t6 is 60 to 90 minutes; and / or

[0058] X1 is 6mm to 10mm; and / or

[0059] X2 is 20mm to 30mm; and / or

[0060] t7 is 24h to 48h; and / or

[0061] T7 is 1300°C to 1400°C; and / or

[0062] t8 is 4h to 6h; and / or

[0063] The fourth sieving is 120-180 mesh.

[0064] In some embodiments, the mass ratio of MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconia, graphite, and short fibers is 55-85:5-10:10-20:0.5-1.5:4:1.

[0065] In some embodiments, MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconium oxide, graphite, and short fibers are mixed in the above-mentioned mass ratio and added to a ball mill, ball-milled to a fifth sieve pass rate of Y, then granulated with water and pressed into a six-hole column or a seven-hole column; cured for t9 under P2 conditions in an autoclave, and finally calcined for t10 at T8 to obtain a catalyst carrier.

[0066] In some embodiments, the fifth sieve has a mesh size of 200 mesh; and / or

[0067] Y is 75% to 85%; and / or

[0068] P2 is 0.8 MPa to 1.2 MPa; and / or

[0069] t9 is 12h to 24h; and / or

[0070] T8 is 1300°C to 1400°C; and / or

[0071] t10 is 4h~6h.

[0072] In some embodiments, the catalyst carrier has a pore size of not less than 75% of pores above 300 nm, a strength of not less than 400 N / particle, a pore volume of 0.3 to 0.4 mL / g, and a specific surface area of ​​5 m 2 / g; and / or

[0073] The catalyst support is immersed in a C9 nickel nitrate solution at room temperature for t11, then dried at T9 for t12 and calcined at T10 for t13; after repeating the above steps, a catalyst having a nickel oxide mass content of C10 is obtained.

[0074] In some embodiments, C9 is 400 g / L to 600 g / L; and / or

[0075] t11 is 30 to 60 minutes; and / or

[0076] T9 is 130°C to 150°C; and / or

[0077] t12 is 8h to 15h; and / or

[0078] T10 is 450°C to 550°C; and / or

[0079] t13 is 4h to 6h; and / or

[0080] C10 is 10% to 15%.

[0081] Beneficial effects:

[0082] The hydrocarbon steam reforming catalyst of the present application has a carrier mainly of a uniform magnesium-aluminum spinel structure with a high-pressure crystallization, and a high-temperature stable potassium calcium aluminate additive and zirconium dioxide added, so that the catalyst carrier has obvious alkalinity and alkaline stability, and obvious anti-carbon deposition effect. The potassium release rate of the high-temperature synthesized potassium calcium aluminate additive is low, which can effectively prevent the fouling of the downstream system caused by the rapid loss of potassium alkali, thereby facilitating the long-period stable operation of the entire reforming section. In addition, the addition of the two structural additives (potassium calcium aluminate additive and zirconium dioxide) can effectively disperse the active component nickel, so that the catalyst has a higher nickel dispersion, which can effectively resist the growth of nickel crystal size caused by high-temperature thermal aging during the operation of the catalyst, and improve the activity stability of the catalyst. BRIEF DESCRIPTION OF DRAWINGS

[0083] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0084] Figure 1 is a flow chart of the preparation method of the hydrocarbon steam reforming catalyst provided by the embodiments of the present application;

[0085] Figure 2 is an activity evaluation device of the catalyst of the embodiments and comparative examples of the present application;

[0086] Figure 3 is a finished product diagram of the catalyst prepared by the embodiments of the present application. DETAILED DESCRIPTION

[0087] The technical solutions in the embodiments of the present application will be described clearly and completely in the following with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application. In addition, it should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0088] In the present application, in addition, in the description of the present application, the term "comprises" means "comprises but is not limited to". The terms first, second, third, etc. are only used as labels, and do not impose numerical requirements or establish sequences.

[0089] In this application, "and / or" describes the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural.

[0090] In this application, "at least one" means one or more, and "plurality" means two or more. "One or several", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0091] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity and should not be understood as a hard limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numbers within the range. For example, the description of a range from 1 to 6 should be considered to have specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which applies regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0092] The technical solution of this application is as follows:

[0093] In a first aspect, embodiments of the present application provide a hydrocarbon steam reforming catalyst, wherein the catalyst includes NiO, ZrO, K2O, Al2O3, CaO, and MgO.

[0094] The hydrocarbon steam reforming catalyst of the present application has a carrier mainly composed of a magnesium-aluminum spinel structure with uniform grain size prepared by high-pressure crystallization, and high-temperature stable potassium calcium aluminate additives and zirconium dioxide are added, so that the catalyst carrier has obvious alkalinity and alkaline stability, and has obvious anti-carbon deposition effect. In addition, the potassium release rate of the high-temperature synthesized potassium calcium aluminate additive is low, which can effectively prevent the scaling of the post-system caused by the rapid loss of potassium alkali, thereby facilitating the long-term stable operation of the entire conversion section; in addition, the addition of these two structural additives (potassium calcium aluminate additive and zirconium dioxide) can effectively disperse the active component nickel, so that the catalyst has a higher nickel dispersion, which can effectively resist the growth of nickel grain size caused by high-temperature thermal aging during the operation of the catalyst, thereby improving the activity stability of the catalyst.

[0095] In some embodiments, the catalyst comprises, by mass percentage, 10% to 15% NiO, 0.5% to 1% ZrO, 1% to 2% K2O, 60% to 75% Al2O3, 3% to 6% CaO, and 10% to 25% MgO.

[0096] Furthermore, the catalyst comprises, by mass percentage, 10% to 15% NiO, preferably 11% to 14% NiO, more preferably 12% to 13% NiO, more preferably 12.5% ​​NiO; 0.5% to 1% ZrO, preferably 0.6% to 0.9% ZrO, more preferably 0.7% to 0.8% ZrO, more preferably 0.75% ZrO; 1% to 2% K2O, preferably 1.2% to 1.8% K2O, more preferably 1.4% to 1.6% K2O, more preferably 1.5% K2O; 60% to 75% Al2O3, preferably 62% to 73% Al2O3, more preferably 65% ​​to 70% Al2O3, more preferably 67% Al2O3; 3% to 6% CaO, preferably 3.5% to 5.5% CaO, more preferably 4% to 5% CaO, more preferably 4.5% CaO; 10% to 25% MgO, preferably 12% to 23% MgO, more preferably 15% to 20% MgO, more preferably 17% MgO.

[0097] See also Figure 1 In a second aspect, the present invention provides a method for preparing a hydrocarbon steam reforming catalyst, comprising:

[0098] S01, providing MgAl2O4 spinel powder;

[0099] S02. Providing potassium calcium aluminate powder;

[0100] S03, MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconium oxide, graphite, and short fibers are ball-milled, granulated with water, pressed, and calcined to obtain a catalyst carrier;

[0101] S04. The catalyst support is immersed in a nickel nitrate solution, dried, and then calcined to obtain a finished catalyst product.

[0102] In this application, the synthesis of MgAl2O4 spinel powder, one of the carrier raw materials, adopts high-pressure crystallization method, and the spinel structure of the powder is stable and uniform in size, with high thermal stability; the synthesis of anti-carbon auxiliary agent potassium calcium aluminate powder adds calcium oxide stabilizer, effectively makes potassium coated in stable calcium aluminate structure, stabilizes potassium source, potassium loss rate is extremely low, with excellent anti-carbon precipitation ability; ZrO2 auxiliary agent is added in the preparation process of catalyst carrier, further improves the alkalinity and thermal stability of carrier; Short fiber filler is also added, and filler forms through-holes during high-temperature calcination, and pore size is large, is convenient for heat transfer and mass transfer in reaction, and can effectively improve the utilization rate of carrier pore; Secondly, the addition of two alkaline auxiliary agents can effectively disperse active component nickel, make catalyst have higher nickel dispersion, can effectively resist catalyst in operation due to thermal aging and cause nickel grain size to grow, significantly extend catalyst service life. The overall preparation process of catalyst is simple, operability is strong, it is very easy to realize industrial production, raw materials are cheap and easy to obtain, and have good industrial application prospects.

[0103] In the S01:

[0104] The preparation method of MgAl2O4 spinel powder includes:

[0105] S011, take a sodium aluminate solution with an aluminum oxide mass concentration of C1, add water to dilute it to an aluminum oxide mass concentration of C2, and heat it to T1 for standby use;

[0106] S012, according to the mass ratio of MgO:HNO3 is m1:m2, magnesium oxide is added to the desalted water of a% of the volume of the reactor according to this mass ratio, and then nitric acid with a mass concentration of C3 is added dropwise and mixed evenly. After grinding, the mixture is first sieved, and finally water is added to prepare the MgO concentration to C4, and the temperature is raised to T2 and set aside;

[0107] S013, adding desalted water with a reactor volume of C5 into the autoclave, raising the temperature to T3, and setting aside;

[0108] S014, adding the above-mentioned standby sodium metaaluminate solution and magnesium oxide slurry to a high-temperature and high-pressure reactor at the same time, the stirring speed of the reactor during the neutralization process is v, the addition time is t1, the whole process is pH, and the reaction temperature is T4;

[0109] S015. After the neutralization reaction is completed, the autoclave is pressurized to a pressure of P1, and the reaction is continued for t2. Then the pressure is reduced to normal pressure, and the material is filtered and washed in a filter until the Na2O content is lower than C6;

[0110] S016. The washed filter cake is dried under conditions T5 for t3, and then calcined under conditions T6 for t4. The calcined material is ball-milled until it passes through the second sieve to obtain MgAl2O4 spinel powder.

[0111] In the S011:

[0112] C1 is 30% to 37%, for example, 30%, 32%, 33%, 35%, 36%, 37%, etc.;

[0113] C2 is 90 g / L to 120 g / L, for example, 90 g / L, 95 g / L, 100 g / L, 105 g / L, 110 g / L, 115 g / L, 120 g / L, etc.;

[0114] T1 is 60°C to 70°C, for example, 60°C, 62°C, 65°C, 66°C, 68°C, 70°C, etc.

[0115] In said S012:

[0116] m1:m2 is 100:5-7, for example, 100:5, 100:5.5, 100:5.8, 100:6, 100:6.2, 100:6.5, 100:6.8, 100:7, etc.;

[0117] C3 is 15% to 20%, for example, 15%, 16%, 17%, 18%, 19%, 20%, etc.;

[0118] C4 is 30 g / L to 50 g / L, for example, 30 g / L, 32 g / L, 35 g / L, 40 g / L, 45 g / L, 50 g / L, etc.;

[0119] T2 is 60°C to 70°C, for example, 60°C, 62°C, 65°C, 66°C, 68°C, 70°C, etc.

[0120] a% is 10% to 15%, for example, it can be 10%, 11%, 12%, 13%, 14%, 15%, etc.;

[0121] It will be appreciated that the amount of magnesium is based on the mass of MgO.

[0122] In some embodiments, milling is performed using a colloid mill.

[0123] In some embodiments, the first sieve has a mesh size of 300 mesh.

[0124] In said S013:

[0125] C5 is 10% to 20%, for example, 10%, 12%, 15%, 16%, 18%, 20%, etc.

[0126] T3 is 60°C to 70°C, for example, 60°C, 62°C, 65°C, 66°C, 68°C, 70°C, etc.

[0127] In said S014:

[0128] v is 300 rpm to 500 rpm, for example, 300 rpm, 350 rpm, 400 rpm, 450 rpm, 500 rpm, etc.;

[0129] t1 is 90 min to 120 min, for example, it can be 90 min, 95 min, 100 min, 105 min, 110 min, 115 min, 120 min, etc.

[0130] The pH is 7 to 8, for example, 7, 7.2, 7.5, 7.6, 7.8, 8, etc.

[0131] T4 is 60°C to 70°C, for example, 60°C, 62°C, 65°C, 66°C, 68°C, 70°C, etc.

[0132] In said S015:

[0133] P1 is 8 MPa to 10 MPa, for example, 8 MPa, 8.5 MPa, 9 MPa, 9.5 MPa, 10 MPa, etc.

[0134] t2 is 12h to 18h, for example, it can be 12h, 13h, 14h, 15h, 16h, 17h, 18h, etc.

[0135] C6 is 0.05%;

[0136] In said S016:

[0137] T5 is 80°C to 120°C, for example, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, etc.;

[0138] t3 is 8h to 20h, for example, 8h, 10h, 12h, 14h, 16h, 18h, 20h, etc.;

[0139] T6 is 1180°C to 1230°C, for example, 1180°C, 1190°C, 1200°C, 1210°C, 1220°C, 1230°C, etc.

[0140] t4 is 3h to 5h, for example, 3h, 3.5h, 4h, 4.5h, 5h, etc.;

[0141] The mesh number of the second sieving is 100-150 mesh, for example, it can be 100 mesh, 105 mesh, 110 mesh, 115 mesh, 120 mesh, 125 mesh, 130 mesh, 135 mesh, 140 mesh, 145 mesh, 150 mesh, etc.

[0142] In the S02:

[0143] The preparation method of potassium calcium aluminate powder comprises:

[0144] S021, based on the Al2O3 content in aluminum hydroxide, add CaO powder with a weight content of C7, ball-mill and mix together, ball-mill to the third sieve, and set aside;

[0145] S022, based on the Al2O3 content in aluminum hydroxide, weigh KOH solid with a weight content of C8, and add deionized water with a weight M of the weighed KOH solid to dissolve it and set aside;

[0146] S023, add the reserved aluminum hydroxide containing CaO into the mixer, mix the dry powder for t5, add the reserved KOH solution and mix for t6; extrude the mixed wet material into strips with a width of X1 and a length of X2, dry it naturally for t7, heat it in a muffle furnace to T7, calcine it for t8, and grind it to the fourth sieve after cooling to obtain potassium calcium aluminate powder with a structure of KCa 1 / 2 Al2O4.

[0147] In said S021:

[0148] C7 is 25% to 30%, for example, 25%, 26%, 27%, 28%, 29%, 30%, etc.

[0149] The mesh number of the third sieving is 250 mesh to 320 mesh, for example, it can be 250 mesh, 260 mesh, 270 mesh, 280 mesh, 290 mesh, 300 mesh, 310 mesh, or 320 mesh.

[0150] In said S022:

[0151] C8 is 40% to 60%, for example, 40%, 42%, 46%, 48%, 50%, 52%, 53%, 55%, 56%, 58%, 60%, etc.

[0152] M is 2.1 to 2.5 times, for example, 2.1, 2.2, 2.3, 2.4, 2.5, etc.

[0153] In said S023:

[0154] It can be understood that the materials are fully mixed and no unwetted solid particles exist.

[0155] t5 is 30 min to 60 min, for example, it can be 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min, etc.

[0156] t6 is 60 min to 90 min, for example, it can be 60 min, 65 min, 70 min, 75 min, 80 min, 85 min, 90 min, etc.

[0157] X1 is 6 mm to 10 mm, for example, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, and 10 mm;

[0158] X2 is 20 mm to 30 mm, for example, it can be 20 mm, 22 mm, 25 mm, 26 mm, 28 mm, or 30 mm.

[0159] t7 is 24h to 48h, for example, 24h, 26h, 28h, 30h, 32h, 34h, 36h, 38h, 40h, 42h, 46h, 48h, etc.;

[0160] T7 is 1300°C to 1400°C, for example, 1300°C, 1320°C, 1340°C, 1360°C, 1380°C, or 1400°C;

[0161] t8 is 4 to 6 hours, for example, 4 hours, 4.5 hours, 5 hours, 5.5 hours, 6 hours, etc.

[0162] The fourth sieving is 120-180 mesh, for example, 120 mesh, 130 mesh, 140 mesh, 150 mesh, 160 mesh, 170 mesh, 180 mesh, etc.

[0163] In said S03:

[0164] In some embodiments, the mass ratio of MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconia, graphite, and short fiber is 55-85:5-10:10-20:0.5-1.5:4:1, for example, it can be 55:5:10:0.5:4:1, 55:7:12:0.8:4:1, 55:8:15:1:4:1, 55:9:18:1.2:4:1, 55:10:20:1.5:4:1, 60:5:10:0.5:4:1, 60:7:12:0.8:4:1, 60:8:15:1:4:1, 60:9:18:1.2:4:1, 60:10:20:1.5:4: 1,70:5:10:0.5:4:1,70:7:12:0.8:4:1,70:8:15:1:4:1,70:9:18:1.2:4:1,70:10:20:1.5:4:1,80:5:10:0.5:4:1,80:7:12:0.8:4:1,80:8:15:1:4:1,80:9:18:1.2:4:1,80:10:20:1.5:4:1,85:5:10:0.5:4:1,85:7:12:0.8:4:1,85:8:15:1:4:1,85:9:18:1.2:4:1,85:10:20:1.5:4:1, etc.

[0165] Furthermore, according to the above mass ratio, MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconium oxide, graphite, and short fibers are mixed and added to a ball mill, and ball-milled to a fifth sieve pass rate of Y. Then, water is added to granulate and pressed into a six-hole column or a seven-hole column; cured for t9 under P2 conditions in an autoclave, and finally calcined for t10 at T8 to obtain a catalyst carrier.

[0166] Furthermore, the mesh number of the fifth sieve is 200 mesh;

[0167] Y is 75% to 85%, for example, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, etc.;

[0168] P2 is 0.8 MPa to 1.2 MPa, for example, 0.8 MPa, 0.9 MPa, 1 MPa, 1.1 MPa, 1.2 MPa, etc.;

[0169] t9 is 12 hours to 24 hours, for example, it can be 12 hours, 14 hours, 16 hours, 18 hours, 20 hours, 22 hours, 24 hours, etc.

[0170] T8 is 1300℃-1400℃, for example, can be 1300℃, 1320℃, 1340℃, 1360℃, 1380℃, 1400℃;

[0171] t10 is 4h-6h, for example, can be 4h, 4.5h, 5h, 5.5h, 6h, etc.

[0172] In some embodiments, the pore size of the catalyst carrier is not less than 75% of the pores with a diameter of 300nm or more, the intensity is not less than 400N / pore, the pore volume is 0.3-0.4mL / g, and the specific surface area of the carrier is greater than or equal to 5m 2 / g.

[0173] In the S04, the C9 is 400g / L-600g / L, for example, can be 400g / L, 450g / L, 500g / L, 550g / L, 600g / L, etc.

[0174] In some embodiments, the catalyst carrier is immersed in a C9 nickel nitrate solution at room temperature for t11, and then calcined at T10 for t13 after drying at T9 for t12; after the above steps are operated again, a catalyst with a nickel oxide mass content of C10 is obtained.

[0175] Further, the C9 is 400g / L-600g / L, for example, can be 400g / L, 450g / L, 500g / L, 550g / L, 600g / L, etc.

[0176] t11 is 30min-60min, for example, can be 30min, 35min, 40min, 45min, 50min, 55min, 60min, etc.

[0177] T9 is 130℃-150℃, for example, can be 130℃, 135℃, 140℃, 145℃, 150℃, etc.

[0178] t12 is 8h-15h, for example, can be 8h, 9h, 10h, 11h, 12h, 13h, 15h, etc.

[0179] T10 is 450℃-550℃, for example, can be 450℃, 460℃, 480℃, 500℃, 520℃, 540℃, 550℃, etc.

[0180] t13 is 4h-6h, for example, can be 4h, 4.5h, 5h, 5.5h, 6h, etc.

[0181] C10 is 10%-15%, for example, can be 10%, 11%, 12%, 13%, 14%, 15%, etc.

[0182] The application will be specifically described below through specific embodiments, and the following embodiments are only part of the embodiments of the application, and are not a limitation of the application.

[0183] Example 1

[0184] This embodiment provides a hydrocarbon steam reforming catalyst, which includes, by mass percentage, 12.0% NiO, 0.8% ZrO2, 1.5% K2O, 65% Al2O3, 4.5% CaO, and 16.2% MgO.

[0185] The preparation method of the hydrocarbon steam reforming catalyst comprises:

[0186] Preparation of MgAl2O4 spinel powder

[0187] A. Sodium aluminate solution preparation: Take 167.7 g of sodium aluminate solution with a 30% alumina concentration and dilute it with water to a concentration of 102 g / L alumina. Bring the solution to a volume of 405 mL and heat to 65°C. Set aside.

[0188] B. Preparation of magnesium oxide slurry: According to the mass ratio of MgO:HNO3=100:6, the measurement of magnesium is based on the mass of MgO. 17g of active magnesium oxide is weighed and added to 405mL of desalted water. Then 5g of 20% nitric acid is added dropwise and mixed evenly. The mixture is then ground with a colloid mill until it passes through 300 mesh. Finally, water is added to make the MgO concentration 40g / L. The mixture is heated to 65°C and set aside.

[0189] C. Add 15% of the volume of desalted water into the autoclave and heat it to 65°C;

[0190] D. The sodium metaaluminate solution and magnesium oxide slurry were added to the high-temperature and high-pressure reactor at a specific flow rate. The stirring speed of the reactor was controlled at 400 rpm during the neutralization process. The addition time was 105 minutes. The pH value was controlled at 7.5 throughout the process and the reaction temperature was 65°C.

[0191] E. After the neutralization reaction is completed, the autoclave is pressurized to 9 MPa and the reaction is continued for 15 hours. Then the pressure is reduced to normal pressure and the material is filtered and washed in a filter until the Na2O content is less than 0.05%;

[0192] F. The washed filter cake was dried at 100°C for 12 hours, then calcined at 1200°C for 4 hours, and the calcined material was ball-milled until it passed through 120 mesh to obtain MgAl2O4 spinel powder;

[0193] Preparation of potassium calcium aluminate:

[0194] Step 1, aluminum hydroxide-calcium oxide material preparation: weigh 24.7g aluminum hydroxide (Al2O3 content is 65%), add 4.5g CaO powder (27.5% by weight) and ball mill together, mix until the powder particle size is 250 mesh and all pass through, set aside;

[0195] Step 2, preparation of KOH solution: based on the aluminum oxide content in aluminum hydroxide, weigh 8.8 g of KOH solid that is 55% of its weight, and add 2.2 times the weight of the weighed KOH solid in deionized water to dissolve it and set aside;

[0196] Step 3: Add the aluminum hydroxide prepared in step 1 into a mixer and mix the dry powder for 45 minutes. After the dry powder is mixed, add the KOH solution prepared in step 2 and mix for 75 minutes to ensure that the materials are fully mixed and no unsoaked solid particles exist. The mixed wet material is extruded into 6 mm strips with a length of 25 mm. After natural drying for 36 hours, it is heated to 1350 ° C in a muffle furnace and calcined for 5 hours. After cooling, it is crushed to 150 mesh and fully passed to obtain potassium calcium aluminate powder with a structure of KCa 1 / 2 Al2O4;

[0197] Vector preparation:

[0198] MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconium oxide, graphite, and short fibers (natural kapok, polyvinyl alcohol fiber, polyester fiber, etc.) are mixed in a ratio of 80:6.5:13:0.9:4:1 and added into a ball mill. The mixture is ball-milled to a 200-mesh pass rate of 80%, and then granulated with water and pressed into a six-hole column or a seven-hole column. The mixture is cured in an autoclave at 1 MPa for 18 hours and finally calcined at 1350°C for 5 hours to obtain a catalyst carrier. The pores of the carrier with a pore diameter of more than 300 nm account for 78%, the strength is 420 N / particle, the pore volume is 0.33 mL / g, and the specific surface area of ​​the carrier is 7.85 m 2 / g;

[0199] The support was immersed in a 550 g / L nickel nitrate solution at room temperature for 45 min, then dried at 140°C for 11 h and calcined at 500°C for 5 h. Following the above steps again, a catalyst having a nickel oxide content of 12.0% was obtained. The finished product of the catalyst prepared in this example is shown in FIG. Figure 3 .

[0200] Example 2

[0201] This embodiment provides a hydrocarbon steam reforming catalyst, which includes, by mass percentage, 10% NiO, 0.5% ZrO, 1% K2O, 75% Al2O3, 3% CaO, and 10.5% MgO.

[0202] The preparation method of the hydrocarbon steam reforming catalyst comprises:

[0203] Preparation of MgAl2O4 spinel powder

[0204] A. Sodium aluminate solution preparation: Take 275g of sodium aluminate solution with a 37% alumina concentration and dilute it with water to an alumina concentration of 90g / L. The volume is 1130mL and the temperature is raised to 62°C. Set aside.

[0205] B. Preparation of magnesium oxide slurry: According to the mass ratio of MgO:HNO3=100:6.5, the measurement of magnesium is based on the mass of MgO. 17.0g of active magnesium oxide is weighed and added to 460mL of desalted water. Then 7g of 15% nitric acid is added dropwise and mixed evenly. After grinding with a colloid mill to a 300 mesh, water is added to prepare the MgO concentration to 35g / L. The mixture is heated to 62°C and set aside.

[0206] C. Add 20% of the volume of desalted water into the autoclave and heat it to 60°C;

[0207] D. The sodium metaaluminate solution and magnesium oxide slurry were added to the high-temperature and high-pressure reactor at a specific flow rate. The stirring speed of the reactor was controlled at 400 rpm during the neutralization process. The addition time was 120 minutes. The pH value was controlled at 7.0 throughout the process. The reaction temperature was 62°C.

[0208] E. After the neutralization reaction is completed, the autoclave is pressurized to 10 MPa and the reaction is continued for 15 hours. Then the pressure is reduced to normal pressure and the material is filtered and washed in a filter until the Na2O content is less than 0.05%;

[0209] F. The washed filter cake was dried at 100°C for 12 hours, then calcined at 1200°C for 4 hours, and the calcined material was ball-milled until 125 mesh was fully passed to obtain MgAl2O4 spinel powder;

[0210] Preparation of potassium calcium aluminate:

[0211] Step 1, aluminum hydroxide-calcium oxide material preparation: weigh aluminum hydroxide (Al2O3 content of 65%) 100g, add 28.5% of its weight of CaO powder 18.54g, ball mill together, mix, ball mill until the powder particle size of 280 mesh passes through, set aside;

[0212] Step 2, preparation of KOH solution: based on the aluminum oxide content in aluminum hydroxide, weigh 28.4 g of KOH solid with a weight of 44% and add 2.5 times the weight of deionized water to dissolve the KOH solid and set aside;

[0213] Step 3: Add the aluminum hydroxide prepared in step 1 into a mixer and mix the dry powder for 45 minutes. After the dry powder is mixed, add the KOH solution prepared in step 2 and mix for 75 minutes to ensure that the materials are fully mixed and no unsoaked solid particles exist. The mixed wet material is extruded into 8mm strips with a length of 25mm. After natural drying for 36 hours, it is heated to 1350℃ in a muffle furnace and calcined for 5 hours. After cooling, it is crushed to 150 mesh and fully passed to obtain potassium calcium aluminate powder with a structure of KCa 1 / 2 Al2O4;

[0214] Vector preparation:

[0215] MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconium oxide, graphite, and short fibers (natural kapok, polyvinyl alcohol fiber, polyester fiber, etc.) are mixed in a ratio of 85:5:10:0.55:4:1 and added into a ball mill. The mixture is ball-milled to a 200-mesh pass rate of 80%, and then granulated with water and pressed into a six-hole column or a seven-hole column. The mixture is cured in an autoclave at 1 MPa for 18 hours and finally calcined at 1350°C for 5 hours to obtain a catalyst carrier. The catalyst carrier has pores with a pore diameter of 300 nm or more, a strength of 410 N / particle, a pore volume of 0.35 mL / g, and a specific surface area of ​​6.5 m 2 / g;

[0216] The support was impregnated in a 500 g / L nickel nitrate solution at room temperature for 45 min, then dried at 140° C. for 11 h and calcined at 500° C. for 5 h. Following the above steps again, a catalyst with a nickel oxide content of 10% was obtained.

[0217] Example 3

[0218] This embodiment provides a hydrocarbon steam reforming catalyst, which comprises, by mass percentage, 15% NiO, 1% ZrO, 2% K2O, 60% Al2O3, 6% CaO, and 16% MgO.

[0219] The preparation method of the hydrocarbon steam reforming catalyst comprises:

[0220] Preparation of MgAl2O4 spinel powder

[0221] A. Sodium aluminate solution preparation: Take 117g of sodium aluminate solution with a 35% alumina concentration and dilute it with water to an alumina concentration of 110g / L. Fill the solution to 375mL and heat to 60°C. Set aside.

[0222] B. Preparation of magnesium oxide slurry: According to the mass ratio of MgO:HNO3=100:5, the measurement of magnesium is based on the mass of MgO. Weigh 17g of active magnesium oxide and add it to 323mL of desalted water. Then add 4.5g of 18% nitric acid dropwise and mix well. Grind with a colloid mill until it passes through 300 mesh. Finally, add water to make the MgO concentration 50g / L. Heat to 60℃ and set aside.

[0223] C. Add 100% of the volume of desalted water into the autoclave and heat it to 60°C;

[0224] D. The sodium metaaluminate solution and magnesium oxide slurry were added to the high-temperature and high-pressure reactor at a specific flow rate. The stirring speed of the reactor was controlled at 400 rpm during the neutralization process. The addition time was 90 minutes. The pH value was controlled at 7.5 throughout the process. The reaction temperature was 60°C.

[0225] E. After the neutralization reaction is completed, the autoclave is pressurized to 10 MPa and the reaction is continued for 15 hours. Then the pressure is reduced to normal pressure and the material is filtered and washed in a filter until the Na2O content is less than 0.05%;

[0226] F. The washed filter cake was dried at 100°C for 12 hours, then calcined at 1200°C for 4 hours, and the calcined material was ball-milled until it passed through 120 mesh to obtain MgAl2O4 spinel powder;

[0227] Preparation of potassium calcium aluminate:

[0228] Step 1, aluminum hydroxide-calcium oxide material preparation: based on the Al2O3 content in aluminum hydroxide, add 27.5% of its weight of CaO powder, ball mill and mix together, ball mill until the powder particle size is 280 mesh and all pass through, and set aside;

[0229] Step 2, preparation of KOH solution: based on the aluminum oxide content in aluminum hydroxide, weigh 55% of the weight of KOH solid, and add 2.1 times the weight of the weighed KOH solid in deionized water to dissolve it and set aside;

[0230] Step 3: Add the aluminum hydroxide prepared in step 1 into a mixer and mix the dry powder for 45 minutes. After the dry powder is mixed, add the KOH solution prepared in step 2 and mix for 75 minutes to ensure that the materials are fully mixed and no unsoaked solid particles exist. The mixed wet material is extruded into 8mm strips with a length of 25mm. After natural drying for 36 hours, it is heated to 1350℃ in a muffle furnace and calcined for 5 hours. After cooling, it is crushed to 150 mesh and fully passed to obtain potassium calcium aluminate powder with a structure of KCa 1 / 2 Al2O4;

[0231] Vector preparation:

[0232] MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconium oxide, graphite, and short fibers (natural kapok, polyvinyl alcohol fiber, polyester fiber, etc.) are mixed in a ratio of 58:9:18:1.3:4:1 and added into a ball mill. The mixture is ball-milled to a 200-mesh pass rate of 80%, and then granulated with water and pressed into a six-hole column or a seven-hole column. The mixture is cured in an autoclave at 1 MPa for 18 hours and finally calcined at 1350°C for 5 hours to obtain a catalyst carrier. The catalyst carrier has 82% pores with a pore diameter of more than 300 nm, a strength of 409 N / particle, a pore volume of 0.37 mL / g, and a specific surface area of ​​6.98 m 2 / g;

[0233] The support was impregnated in a 600 g / L nickel nitrate solution at room temperature for 45 min, then dried at 140° C. for 11 h and calcined at 500° C. for 5 h. Following the above steps again, a catalyst with a nickel oxide content of 15% was obtained.

[0234] Example 4

[0235] This embodiment provides a hydrocarbon steam reforming catalyst, which comprises, by mass percentage, 13% NiO, 0.6% ZrO, 1.4% K2O, 60% Al2O3, 5% CaO, and 20% MgO.

[0236] The preparation method of the hydrocarbon steam reforming catalyst is the same as that in Example 1.

[0237] Example 5

[0238] This embodiment provides a hydrocarbon steam reforming catalyst, which comprises, by mass percentage, 14% NiO, 0.7% ZrO, 1.3% K2O, 68% Al2O3, 4% CaO, and 12% MgO.

[0239] The preparation method of the hydrocarbon steam reforming catalyst is the same as that in Example 1.

[0240] Example 6

[0241] This embodiment provides a hydrocarbon steam reforming catalyst, which comprises, by mass percentage, 12% NiO, 0.8% ZrO2, 1.5% K2O, 65% Al2O3, 4.5% CaO, and 16.2% MgO.

[0242] The preparation method of the hydrocarbon steam reforming catalyst comprises:

[0243] Preparation of MgAl2O4 spinel powder

[0244] A. Sodium aluminate solution preparation: Take 167.7 g of sodium aluminate solution with a 30% alumina concentration and dilute it with water to an alumina concentration of 102 g / L. Bring the solution to a volume of 405 mL and heat to 60°C. Set aside.

[0245] B. Preparation of magnesium oxide slurry: According to the mass ratio of MgO:HNO3=100:6, the measurement of magnesium is based on the mass of MgO. 17g of active magnesium oxide is weighed and added to 405mL of desalted water. Then 5g of 20% nitric acid is added dropwise and mixed evenly. The mixture is then ground with a colloid mill until it passes through 300 mesh. Finally, water is added to make the MgO concentration 40g / L. The mixture is heated to 60℃ and set aside.

[0246] C. Add 15% of the volume of desalted water into the autoclave and heat it to 60°C;

[0247] D. The sodium metaaluminate solution and magnesium oxide slurry were added to the high temperature and high pressure reactor at a specific flow rate. The stirring speed of the reactor was controlled at 300 rpm during the neutralization process. The addition time was 90 minutes. The pH value was controlled at 7 during the entire process. The reaction temperature was 60°C.

[0248] E. After the neutralization reaction is completed, the autoclave is pressurized to 9 MPa and the reaction is continued for 15 hours. Then the pressure is reduced to normal pressure and the material is filtered and washed in a filter until the Na2O content is less than 0.05%;

[0249] F. The washed filter cake was dried at 80°C for 20 hours, then calcined at 1180°C for 5 hours, and the calcined material was ball-milled until 100 meshes passed through, thereby obtaining MgAl2O4 spinel powder;

[0250] Preparation of potassium calcium aluminate:

[0251] Step 1, aluminum hydroxide-calcium oxide material preparation: weigh 24.7g aluminum hydroxide (Al2O3 content is 65%), add 4.5g CaO powder (27.5% by weight) and ball mill together, mix until the powder particle size is 250 mesh and all pass through, set aside;

[0252] Step 2, preparation of KOH solution: based on the aluminum oxide content in aluminum hydroxide, weigh 8.8 g of KOH solid that is 55% of its weight, and add 2.2 times the weight of the weighed KOH solid in deionized water to dissolve it and set aside;

[0253] Step 3: Add the aluminum hydroxide prepared in step 1 into a mixer and mix the dry powder for 30 minutes. After the dry powder is mixed, add the KOH solution prepared in step 2 and mix for 60 minutes to ensure that the materials are fully mixed and no unsoaked solid particles exist. The mixed wet material is extruded into 6mm strips with a length of 20mm. After natural drying for 24 hours, it is heated to 1300℃ in a muffle furnace and calcined for 6 hours. After cooling, it is crushed to 120 mesh and fully passed to obtain potassium calcium aluminate powder with a structure of KCa 1 / 2 Al2O4;

[0254] Vector preparation:

[0255] MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconium oxide, graphite, and short fibers (natural kapok, polyvinyl alcohol fiber, polyester fiber, etc.) are mixed in a ratio of 80:6.5:13:0.9:4:1 and added into a ball mill. The mixture is ball-milled to a 200-mesh pass rate of 75%, and then granulated with water and pressed into a six-hole column or a seven-hole column. The mixture is cured in an autoclave at 0.8 MPa for 24 hours and finally calcined at 1300°C for 6 hours to obtain a catalyst carrier. The pores of the carrier with a pore diameter of more than 300 nm account for 78%, the strength is 414 N / particle, the pore volume is 0.35 mL / g, and the specific surface area of ​​the carrier is 7.13 m 2 / g;

[0256] The support was impregnated in a 400 g / L nickel nitrate solution at room temperature for 60 min, then dried at 130° C. for 15 h and calcined at 450° C. for 6 h. Following the above steps again, a catalyst having a nickel oxide content of 12.0% was obtained.

[0257] Example 7

[0258] This embodiment provides a hydrocarbon steam reforming catalyst, which includes, by mass percentage, 12.0% NiO, 0.8% ZrO2, 1.5% K2O, 65% Al2O3, 4.5% CaO, and 16.2% MgO.

[0259] The preparation method of the hydrocarbon steam reforming catalyst comprises:

[0260] Preparation of MgAl2O4 spinel powder

[0261] A. Sodium aluminate solution preparation: Take 167.7 g of sodium aluminate solution with a 30% alumina concentration and dilute it with water to a concentration of 102 g / L alumina. Bring the solution to a volume of 405 mL and heat to 70°C. Set aside.

[0262] B. Preparation of magnesium oxide slurry: According to the mass ratio of MgO:HNO3=100:6, the measurement of magnesium is based on the mass of MgO. 17g of active magnesium oxide is weighed and added to 405mL of desalted water. Then 5g of 20% nitric acid is added dropwise and mixed evenly. The mixture is then ground with a colloid mill until it passes through 300 mesh. Finally, water is added to make the MgO concentration 40g / L. The mixture is heated to 70℃ and set aside.

[0263] C. Add 15% of the volume of desalted water into the autoclave and heat it to 70°C;

[0264] D. The sodium metaaluminate solution and magnesium oxide slurry were added to the high temperature and high pressure reactor at a specific flow rate. The stirring speed of the reactor was controlled at 500 rpm during the neutralization process. The addition time was 120 min. The pH value was controlled at 8 throughout the process. The reaction temperature was 70°C.

[0265] E. After the neutralization reaction is completed, the autoclave is pressurized to 10 MPa and the reaction is continued for 18 hours. Then the pressure is reduced to normal pressure and the material is filtered and washed in a filter until the Na2O content is less than 0.05%;

[0266] F. The washed filter cake was dried at 120°C for 8 hours, then calcined at 1230°C for 3 hours, and the calcined material was ball-milled until it passed through 150 mesh to obtain MgAl2O4 spinel powder;

[0267] Preparation of potassium calcium aluminate:

[0268] Step 1, aluminum hydroxide-calcium oxide material preparation: weigh 24.7g aluminum hydroxide (Al2O3 content is 65%), add 4.5g CaO powder (27.5% by weight) and ball mill together, mix until the powder particle size is 320 mesh and all pass through, set aside;

[0269] Step 2, preparation of KOH solution: based on the aluminum oxide content in aluminum hydroxide, weigh 8.8 g of KOH solid that is 55% of its weight, and add 2.2 times the weight of the weighed KOH solid in deionized water to dissolve it and set aside;

[0270] Step 3: Add the aluminum hydroxide prepared in step 1 into a mixer and mix the dry powder for 60 minutes. After the dry powder is mixed, add the KOH solution prepared in step 2 and mix for 90 minutes to ensure that the materials are fully mixed and no unsoaked solid particles exist. The mixed wet material is extruded into 10 mm strips with a length of 30 mm. After natural drying for 48 hours, it is heated to 1400 ° C in a muffle furnace and calcined for 4 hours. After cooling, it is crushed to 180 mesh and fully passed to obtain potassium calcium aluminate powder with a structure of KCa 1 / 2 Al2O4;

[0271] Vector preparation:

[0272] MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconium oxide, graphite, and short fibers (natural kapok, polyvinyl alcohol fiber, polyester fiber, etc.) were mixed in a ratio of 80:6.5:13:0.9:4:1 and added into a ball mill. The mixture was ball-milled to 200°C with a pass rate of 85%. Water was then added to granulate the mixture and press-molded into a six-hole column or a seven-hole column. The mixture was cured in an autoclave at 1.2 MPa for 12 hours and finally calcined at 1400°C for 4 hours to obtain a catalyst carrier. The catalyst carrier had a pore size of 73% with a pore size of 300 nm or more, a strength of 419 N / particle, a pore volume of 0.31 mL / g, and a specific surface area of ​​6.81 m 2 / g;

[0273] The support was immersed in a 600 g / L nickel nitrate solution at room temperature for 30 min, then dried at 150° C. for 8 h and calcined at 550° C. for 4 h. Following the above steps again, a catalyst with a nickel oxide content of 12.0% was obtained.

[0274] Comparative Example 1

[0275] The samples were prepared according to the catalyst preparation method in patent CN201410528730.9.

[0276] Potassium loss rate determination:

[0277] The catalyst samples of Examples 1 to 7 and the comparative example were ground to 80-100 mesh, and samples were taken according to the quartering method. One portion was analyzed for K2O content in the catalyst according to HG / T, and one portion was immersed in 200 mL of water and heated under reflux for 6 h. The catalyst was then dried and the K2O content in the catalyst after boiling was analyzed according to HG / T.

[0278] Table 1 Potassium loss rate determination of the conversion catalyst prepared in Example before and after boiling

[0279]

[0280]

[0281] The test results show that the potassium fixation effect of the catalyst prepared by the present invention is significantly better than that of the traditional potassium fixation method.

[0282] Comparison of catalyst activity:

[0283] The activity of the catalysts prepared using Examples 1 to 7 and the comparative example of the present application was tested as follows:

[0284] (1) Catalyst loading:

[0285] Figure 2The activity evaluation device for the catalysts of the examples and comparative examples of the present application is first loaded into the isothermal zone of the reactor (the fixed bed reactor is a Φ25×3mm stainless steel tube) with the catalyst sample of the example or comparative example (catalyst particle size is 10-20 mesh, catalyst loading amount is 20mL, catalyst bed height is 750mm), and the raw material is isobutane (purity ≥99.99%) to measure the activity of the catalyst.

[0286] The analytical instrument used was a Sichuan Instrument SC-2000 gas chromatograph with a thermal conductivity detector, a TDX-01 column, and H2 as the carrier gas. The main analysis was for C2 in the gas. + content.

[0287] (2) Test conditions are shown in Table 2:

[0288] Table 2 Test conditions for the activity of the conversion catalyst prepared in Example

[0289] condition Temperature / ℃ Pressure / MPa <![CDATA[干气空速 / h -1 ]]> Water-carbon ratio reduction 800 0.5 2000 \ Activity test 750 3.0 6000 2.5

[0290] (3) The test results of CH4 and C2 content in the conversion gas are shown in Table 3:

[0291] Table 3 Test results of catalysts prepared in Example and comparative example catalysts

[0292]

[0293]

[0294] (4) The carbon deposition resistance of some catalysts in the examples and the catalyst in comparative example 1 (measured using a TGA-101 thermogravimetric analyzer) is shown in Table 4:

[0295] Table 4 Test results of the carbon deposition resistance of the catalysts of Example 4 and Comparative Example 1

[0296]

[0297] From the comparative data in Table 3 and Table 4, it can be seen that the catalyst prepared by the method described in this scheme is mainly composed of a magnesium-aluminum spinel structure with uniform grain size prepared by high-pressure crystallization, and is added with high-temperature stable potassium calcium aluminate additives and zirconium dioxide, so that the catalyst carrier has obvious alkalinity and alkaline stability. The anti-carbon deposition effect of the catalyst is significantly better than that of the embodiment, the CH4 content in the converted gas is lower, the activity of the catalyst is higher, and the occurrence of carbon deposition during the operation of the catalyst, which affects the activity and service life, can be significantly reduced.

[0298] Table 5 Comparison of Ni crystal dispersion of catalysts (analyzed by XRD-6100 X-ray diffractometer)

[0299]

[0300]

[0301] From the comparison of Ni grain size before and after the operation of the catalyst in Table 5, it can be seen that the catalyst prepared by the method described in this scheme is mainly composed of a magnesium-aluminum spinel structure with uniform grain size prepared by high-pressure crystallization, and is added with high-temperature stable potassium calcium aluminate additives and zirconium dioxide. The stability of the carrier structure and the addition of the two structural additives can effectively disperse the active component nickel, so that the catalyst has a higher nickel dispersion, effectively resisting the growth of nickel grain size caused by high-temperature thermal aging during the operation of the catalyst. The catalyst has good stability and can ensure a long service life of the catalyst during industrial application.

[0302] The above is a detailed introduction to the hydrocarbon steam reforming catalyst and its preparation method provided in the examples of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for technical personnel in this field, based on the ideas of the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present application.

Claims

1. A hydrocarbon steam reforming catalyst, characterized in that: The catalyst includes NiO, ZrO, K2O, Al2O3, CaO, and MgO.

2. The hydrocarbon steam reforming catalyst according to claim 1, characterized in that Calculated by mass percentage, the catalyst includes 10% to 15% NiO, 0.5% to 1% ZrO, 1% to 2% K2O, 60% to 75% Al2O3, 3% to 6% CaO, and 10% to 25% MgO.

3. A method for preparing a hydrocarbon steam reforming catalyst, characterized in that: include: Provide MgAl2O4 spinel powder; Provide potassium calcium aluminate powder; MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconium oxide, graphite, and short fibers are ball-milled, granulated with water, pressed, and calcined to obtain a catalyst carrier; The catalyst carrier is impregnated in a nickel nitrate solution, dried and then calcined to obtain a finished catalyst product.

4. The preparation method according to claim 3, characterized in that The preparation method of MgAl2O4 spinel powder includes: Take a sodium aluminate solution with an alumina mass concentration of C1, dilute it with water to an alumina mass concentration of C2, and heat it to T1 for later use; According to the mass ratio of MgO:HNO3 of m1:m2, magnesium oxide is added to the desalted water of a% of the volume of the reactor, and then nitric acid with a mass concentration of C3 is added dropwise and mixed evenly. After grinding, the mixture is first sieved, and finally water is added to prepare the MgO concentration to C4, and the temperature is raised to T2 for standby use; Add desalted water with a volume of C5 into the autoclave, raise the temperature to T3, and set aside; The above-mentioned sodium metaaluminate solution and magnesium oxide slurry are added to the high temperature and high pressure reactor at the same time. The stirring speed of the reactor during the neutralization process is v, the addition time is t1, the pH value of the whole process is t4, and the reaction temperature is T4; After the neutralization reaction is completed, the autoclave is pressurized to P1, the reaction is continued for t2, and then the pressure is reduced to normal pressure. The material is filtered and washed in a filter until the Na2O content is lower than C6; The washed filter cake is dried under conditions T5 for t3, then calcined under conditions T6 for t4, and the calcined material is ball-milled until the second sieving is performed to obtain MgAl2O4 spinel powder; and / or The preparation method of potassium calcium aluminate powder comprises: Based on the Al2O3 content in aluminum hydroxide, add CaO powder with a weight content of C7, ball mill and mix together, ball mill to the third sieve, and set aside; Based on the Al2O3 content in aluminum hydroxide, weigh the KOH solid with a weight content of C8, and add deionized water with a weight M of the weighed KOH solid to dissolve it and set aside; Add the spare aluminum hydroxide containing CaO into the mixer, mix the dry powder for t5, add the above-mentioned spare KOH solution and mix for t6; the mixed wet material is extruded into strips with a width of X1 and a length of X2, and naturally dried for t7, and then heated to T7 in a muffle furnace and calcined for t8, and then pulverized to the fourth sieve after cooling to obtain potassium calcium aluminate powder with a structure of KCa 1 / 2 Al2O4.

5. The preparation method according to claim 4, characterized in that C1 is 30% to 37%; and / or C2 is 90g / L to 120g / L; and / or T1 is 60°C to 70°C; and / or m1:m2 is 100:5-7; and / or C3 is 15% to 20%; and / or C4 is 30g / L to 50g / L; and / or T2 is 60°C to 70°C; and / or a% is 10% to 15%; and / or The first sieve has a mesh size of 300; and / or C5 is 10% to 20%; and / or T3 is 60°C to 70°C; and / or v is 300 rpm to 500 rpm; and / or t1 is 90 min to 120 min; and / or pH 7-8; and / or T4 is 60°C to 70°C; and / or P1 is 8MPa to 10MPa; and / or t2 is 12h to 18h; and / or C6 is 0.05%; and / or T5 is 80°C to 120°C; and / or t3 is 8h to 20h; and / or T6 is 1180°C to 1230°C; and / or t4 is 3h to 5h; and / or The mesh size of the second sieve is 100-150 mesh; and / or C7 is 25% to 30%; and / or The mesh size of the third sieve is 250-320 mesh; and / or C8 is 40% to 60%; and / or M is 2.1 to 2.5 times; and / or t5 is 30 to 60 minutes; and / or t6 is 60 min to 90 min; and / or X1 is 6mm to 10mm; and / or X2 is 20mm to 30mm; and / or t7 is 24h to 48h; and / or T7 is 1300°C to 1400°C; and / or t8 is 4h to 6h; and / or The fourth sieving is 120-180 mesh.

6. The preparation method according to claim 3, characterized in that The mass ratio of MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconia, graphite and short fiber is 55-85:5-10:10-20:0.5-1.5:4:

1.

7. The preparation method according to claim 6, characterized in that According to the above mass ratio, MgAl2O4 spinel powder, potassium calcium aluminate powder, pure calcium aluminate cement, zirconium oxide, graphite, and short fibers are mixed and added to a ball mill. The mixture is ball-milled to a fifth sieve pass rate of Y. Water is then added to granulate the mixture, and the mixture is pressed into a six-hole column or a seven-hole column. The mixture is cured in an autoclave under P2 conditions for t9, and finally calcined at T8 for t10 to obtain a catalyst carrier.

8. The preparation method according to claim 7, characterized in that The mesh size of the fifth sieve is 200 mesh; and / or Y is 75% to 85%; and / or P2 is 0.8 MPa to 1.2 MPa; and / or t9 is 12h to 24h; and / or T8 is 1300°C to 1400°C; and / or t10 is 4h~6h.

9. The preparation method according to claim 3, characterized in that The pore size of the catalyst carrier is not less than 75% of the pores above 300nm, the strength is not less than 400N / particle, the pore volume is 0.3-0.4mL / g, and the specific surface area of ​​the carrier is greater than or equal to 5m 2 / g; and / or The catalyst support is immersed in a C9 nickel nitrate solution at room temperature for t11, then dried at T9 for t12 and calcined at T10 for t13; after repeating the above steps, a catalyst having a nickel oxide mass content of C10 is obtained.

10. The preparation method according to claim 9, characterized in that C9 is 400g / L to 600g / L; and / or t11 is 30 to 60 minutes; and / or T9 is 130°C to 150°C; and / or t12 is 8h to 15h; and / or T10 is 450°C to 550°C; and / or t13 is 4h to 6h; and / or C10 is 10% to 15%.

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