A sulfur-tolerant shift catalyst and a method for preparing the same

Abstract

The application discloses a preparation method of a sulfur-tolerant shift catalyst, and comprises the following steps: 1) dissolving a cobalt soluble salt and a lanthanide metal soluble salt in a first solvent to obtain solution A, and dissolving an ammonium molybdate salt in a second solvent to obtain solution B; 2) adding calcium-based montmorillonite powder into solution A, and then adding solution B into solution A, and then adding tetrabutyl titanate into solution A, and then keeping the temperature at 60-80 DEG C for aging, and then drying at 100-150 DEG C, and then crushing to 180-200 meshes to obtain pillared montmorillonite; and 3) adding an aluminum-containing compound and magnesium oxide powder into the pillared montmorillonite, adding a binder, kneading uniformly, extruding into a shape, drying, and then calcining at 500-550 DEG C to obtain the sulfur-tolerant shift catalyst. The catalyst preparation method is simple and easy to implement, has strong mass transfer and heat transfer capacity, can effectively reduce the occurrence of methanation side reactions, avoids the safety risks caused by the methanation reaction, reduces the consumption of effective gas, and realizes the safe and stable operation of a device.

Description

Technical Field

[0001] The present invention relates to the field of catalyst technology, in particular to a sulfur-resistant conversion catalyst for preparing chemical raw materials such as synthesis gas, hydrogen and methanol from heavy raw materials such as coal and petroleum coke, and a preparation method thereof. Background Art

[0002] Co-Mo sulfur-tolerant shift catalysts, with their excellent sulfur tolerance and high activity for the CO shift reaction, have been widely used in the coal chemical industry. With the development of coal gasification processes, the CO content in process gases has increased. Under high CO content and low water-gas ratio conditions, methanation side reactions can occur when the catalyst bed temperature exceeds 350°C. This reaction intensifies as the bed temperature increases, leading to reduced product yield and the risk of overheating. For gasification processes with low water-gas ratios, such as Shell pulverized coal gasification and GSP gasification, methanation side reactions pose a challenge to operators, especially during startup, when the water-gas ratio is difficult to control, making overheating and even runaway temperatures caused by methanation side reactions more likely. Currently, designers primarily rely on controlling various shift process conditions to minimize the occurrence of methanation side reactions, thereby suppressing or preventing their occurrence. However, methanation side reactions are still unavoidable in practical applications.

[0003] Montmorillonite is a clay that absorbs large amounts of water and expands significantly. Its silica layers contain numerous hydroxyl groups. Pillared montmorillonite utilizes the exchangeable nature of cations or molecules between montmorillonite mineral layers. Through chemical modification, the target organic or inorganic compound is introduced into the montmorillonite interlayers, exchanging the metal cations within the montmorillonite for the resulting porous material with a two-dimensional pore structure. It exhibits a large specific surface area, high surface activity, a regularly distributed pore structure, and adjustable pore size.

[0004] The invention patent application with Chinese patent publication number CN116060071A discloses a high thermal conductivity and sulfur-resistant conversion catalyst and a preparation method thereof. A certain amount of SiC is placed in a container, and a certain amount of ethanol and a surfactant are added to obtain a first mixture; a certain amount of a high specific surface area carrier precursor is mixed with the first mixture and stirred for 1-24 hours to form a second mixture; a certain amount of water, nitric acid, and ethanol are mixed to obtain a third mixture, the third mixture is slowly dripped into the second mixture, the temperature is increased and stirred until the ethanol is completely evaporated to obtain a colloidal solid; the colloidal solid is dried and calcined to obtain a catalyst carrier; a certain amount of molybdenum source and cobalt source are taken, dissolved in water to obtain two solutions, the two solutions respectively containing molybdenum and cobalt, and then the catalyst carrier is successively impregnated with the two solutions, followed by drying and calcining to obtain the sulfur-resistant conversion catalyst. The catalyst of this patent mainly relies on the thermal conductivity and semiconductor properties of SiC to achieve rapid electron transfer. By using a high specific surface area carrier for coating and modification, the specific surface area of ​​the catalyst is increased, thereby achieving a double improvement in thermal conductivity and catalytic performance. It is suitable for isothermal conversion processes, but for conventional sulfur-resistant conversion processes and reactors, it cannot solve the problem of methanation side reactions.

[0005] The invention patent of Chinese Patent Publication No. CN116116424A discloses a preparation method of a bifunctional sulfur-resistant shift catalyst, comprising kneading pseudo-boehmite powder and magnesium material; after kneading, adding a binder, a dispersant and a pore-enlarging agent and continuing to knead, wherein the magnesium material is one or a combination of magnesium oxide, magnesium carbonate, magnesium hydroxide and magnesium nitrate; the binder is one or a combination of sesbania powder, sodium carboxymethyl cellulose, high alumina cement, bentonite and hydroxypropyl methylcellulose; after the kneaded materials are uniformly kneaded, a molybdenum source is added. , cobalt source, rare earth metal, metal additive and deionized water are prepared into a clear solution, which is then added to a kneader for kneading; the kneaded material is put into an extruder for extrusion and then dried, using a mesh belt kiln for drying; the dried product is sprayed with citric acid solution through a spraying production line, and the spraying amount of citric acid solution is 60-105kg per ton of catalyst. The product is transported on the spraying production line for no less than 4.5 hours, and is transported to a secondary drying equipment for secondary drying while being sprayed. After the secondary drying is completed, the catalyst is roasted to obtain the catalyst. The catalyst in this patent is prepared using a new preparation process, which has a simple preparation process and low cost. It also has transformation and hydrolysis functions, but it cannot effectively inhibit the methanation side reaction. Summary of the Invention

[0006] Based on the problems of the prior art, the present invention provides a sulfur-tolerant shift catalyst and a preparation method thereof, which are simple and easy to implement, and have strong mass and heat transfer capabilities. Compared with the current industrial sulfur-tolerant shift catalysts, the present invention can effectively reduce the occurrence of methanation side reactions under the same conditions, avoid the safety risks brought by the methanation reaction, reduce effective gas consumption, and achieve safe and stable operation of the device, with good economic benefits and application prospects.

[0007] The technical solutions provided by the present invention are as follows:

[0008] A first aspect of the present invention provides a method for preparing a sulfur-tolerant shift catalyst, comprising:

[0009] 1) dissolving a soluble salt of cobalt and a soluble salt of a lanthanide metal in a first solvent and heating the mixture to 60-80° C. to obtain solution A; dissolving an ammonium salt of molybdenum in a second solvent and heating the mixture to 60-80° C. to obtain solution B;

[0010] 2) Calcium-based montmorillonite powder is then added to solution A and stirred evenly. Solution B is then added to solution A and stirred evenly. Tetrabutyl titanate is then added and stirred evenly. The mixture is matured at 60-80°C, dried at 100-150°C, and then pulverized to 180-200 mesh to obtain pillared montmorillonite containing the active ingredient and the additive.

[0011] 3) adding aluminum-containing compound powder and magnesium oxide powder to the pillared montmorillonite powder, mixing uniformly, adding an appropriate amount of binder and kneading uniformly, extruding into a shape, performing a second drying, and calcining at 500-550° C. to obtain a sulfur-resistant shift catalyst;

[0012] Wherein, in step 1), the amount of the soluble cobalt salt added is 1%-8% of the mass of the catalyst calculated as cobalt oxide, the amount of the soluble salt of the lanthanide metal added is 0.2%-4% of the mass of the catalyst calculated as its oxide; the amount of the ammonium salt of molybdenum added is 4%-12% of the mass of the catalyst calculated as molybdenum oxide;

[0013] In step 2), the amount of calcium-montmorillonite added is 20%-30% of the mass of the catalyst;

[0014] In step 3), the aluminum-containing compound powder is 30%-45% of the catalyst mass as calculated as aluminum oxide; and the magnesium oxide is added in an amount of 10%-15% of the catalyst mass.

[0015] Preferably, in step 1), the soluble salt of cobalt is nitrate and / or acetate.

[0016] Preferably, in step 1), the soluble salt of the lanthanide metal is a nitrate.

[0017] Preferably, in step 1), the ammonium acid salt of molybdenum is ammonium molybdate.

[0018] Preferably, in step 1), the soluble salt of cobalt is added in an amount of 2%-4% of the mass of the catalyst in terms of cobalt oxide, the soluble salt of the lanthanide series metal is added in an amount of 0.5%-1.5% of the mass of the catalyst in terms of its oxide, and the ammonium acid salt of molybdenum is added in an amount of 6.5%-9.0% of the mass of the catalyst in terms of molybdenum oxide.

[0019] Preferably, in step 2), the calcium-based montmorillonite has a pH of 7.5-8.5.

[0020] Preferably, in step 3), the magnesium oxide and aluminum oxide are added in a mass ratio of 1:2.0-4.5.

[0021] Preferably, the binder is citric acid, and the binder is added in an amount of 3%-5% of the mass of the catalyst.

[0022] Preferably, the calcination is performed for 2-4h.

[0023] The second aspect of the present application provides a sulfur-tolerant shift catalyst prepared by the above preparation method.

[0024] The beneficial effects of the present application at least include:

[0025] The present application provides a sulfur-tolerant shift catalyst and a preparation method thereof, which is simple and easy to implement. The catalyst introduces a pillared montmorillonite material, and the active components and additives are introduced into the interlayer of the montmorillonite by chemical modification to form a pillared montmorillonite (especially a cobalt-molybdenum-cerium pillared montmorillonite) structure, so that the active components are dispersed in the interlayer of the montmorillonite, and the active metals are dispersed in the interlayer of the montmorillonite, which is beneficial to the reaction and the conduction of reaction heat, thereby enhancing the thermal conductivity of the catalyst, strengthening the mass and heat transfer performance of the catalyst carrier, reducing the internal hotspot temperature of the catalyst, and improving the interlayer water content by using the hydrophilic groups in the interlayer of the montmorillonite. The mass and heat transfer capacity of the catalyst is stronger, and compared with the current industrial sulfur-tolerant shift catalyst, the catalyst can effectively reduce the occurrence of methanation side reactions under the same conditions, avoid the safety risks caused by methanation reactions, reduce the consumption of effective gas, realize the safe and stable operation of the device, and has good economic benefits and application prospect.

[0026] Other features and advantages of the present application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a schematic diagram of a pressurized activity evaluation device in the test example.

[0028] Figure 2This is a chromatogram of the tail gas after the physicochemical performance and pressurized activity test of the sulfur-resistant catalyst in Example 1 of the present invention.

[0029] Figure 3 This is the chromatogram of the tail gas after the physical and chemical performance and pressurized activity test of the conventional sulfur-resistant catalyst QCS-03.

[0030] Description of Reference Numerals

[0031] Figure 1 : 1. Raw gas purifier; 2. Pressure reducer; 3. Mixer; 4. Pressure gauge; 5. Shutdown valve; 6. Heating furnace; 7. Reaction tube; 8. Thermocouple tube in tube; 9. Condenser; 10. Separator; 11. Drain; 12. Wet flow meter; 13. Vaporizer; 14. Water tank; 15. Water metering pump. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and beneficial effects of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. Examples of the embodiments are shown in the accompanying drawings. It should be understood that the specific embodiments described in the following embodiments of the present invention are only exemplary descriptions of the specific embodiments of the present invention, intended to be used for explaining the present invention, and do not constitute a limitation of the present invention.

[0033] The endpoints of the scope disclosed in this article and any value are not limited to this accurate scope or value, and these scopes or values ​​should be interpreted as comprising the value approaching these scopes or value.For numerical range, between the endpoint values ​​of each scope, between the endpoint values ​​of each scope and a separate point value, and between the separate point value, can be combined with each other and obtain one or more new numerical ranges, and these numerical ranges should be considered as specifically disclosed in this article.In the description of the application, unless otherwise stated, the implication of similar terms such as "one / a kind", "a plurality of / a variety" is two / kinds or more than two / kinds.

[0034] A first aspect of the present invention provides a method for preparing a sulfur-tolerant shift catalyst, comprising:

[0035] 1) dissolving a soluble salt of cobalt and a soluble salt of a lanthanide metal in a first solvent and heating the mixture to 60-80° C. to obtain solution A; dissolving an ammonium salt of molybdenum in a second solvent and heating the mixture to 60-80° C. to obtain solution B;

[0036] 2) Calcium-based montmorillonite powder is then added to solution A and stirred evenly. Solution B is then added to solution A and stirred evenly. Tetrabutyl titanate is then added and stirred evenly. The mixture is matured at 60-80°C, dried at 100-150°C, and then pulverized to 180-200 mesh to obtain pillared montmorillonite containing the active ingredient and the additive.

[0037] 3) adding the aluminum-containing compound powder and the magnesium oxide powder into the powder of the pillared montmorillonite, mixing uniformly, adding an appropriate amount of binder, kneading uniformly, extruding into a shape, carrying out a second drying, and calcining at 500-550°C to obtain a sulfur shift-resistant catalyst;

[0038] In step 1), the soluble salt of cobalt is added in an amount of 1%-8% of the mass of the catalyst in terms of cobalt oxide, and the soluble salt of a lanthanide metal is added in an amount of 0.2%-4% of the mass of the catalyst in terms of its oxide; the ammonium acid salt of molybdenum is added in an amount of 4%-12% of the mass of the catalyst in terms of molybdenum oxide.

[0039] In step 2), the calcium-based montmorillonite is added in an amount of 20%-30% of the mass of the catalyst.

[0040] In step 3), the aluminum-containing compound powder is added in an amount of 30%-45% of the mass of the catalyst in terms of aluminum oxide, and the magnesium oxide is added in an amount of 10%-15% of the mass of the catalyst.

[0041] In some preferred embodiments of the present application, in step 1), the soluble salt of cobalt is a nitrate salt and / or an acetate salt. More preferably, the soluble salt of cobalt is cobalt nitrate.

[0042] In some preferred embodiments of the present application, in step 1), the soluble salt of a lanthanide metal is a nitrate salt. More preferably, the soluble salt of a lanthanide metal is cerium nitrate.

[0043] In some preferred embodiments of the present application, in step 1), the ammonium acid salt of molybdenum is ammonium molybdate.

[0044] In some preferred embodiments of the present application, in step 1), the first solvent is deionized water, which facilitates subsequent ion exchange and drying.

[0045] In some preferred embodiments of the present application, in step 1), the second solvent is deionized water, which facilitates subsequent ion exchange and drying.

[0046] According to the present application, in step 1), the temperature at which the heating to obtain solution A is carried out is 60-80°C, and specifically, for example, can be 60°C, 65°C, 70°C, 78°C, 80°C, and any value in the range constituted by any two of these point values.

[0047] According to the present application, in step 1), the temperature at which the heating to obtain solution B is carried out is 60-80°C, and specifically, for example, can be 60°C, 65°C, 70°C, 78°C, 80°C, and any value in the range constituted by any two of these point values.

[0048] The sulfur-tolerant catalyst prepared by using calcium-based montmorillonite in the present application has calcium salt which is not easy to flow out, and can effectively reduce the occurrence of methanation side reactions. The present inventors found that if sodium-based montmorillonite is used, the sodium salt in the catalyst is easy to flow out, which promotes the methanation side reactions, and the content of CH4 in the outlet is too high, which cannot achieve the purpose of the present application, see Comparative Example 3 and data.

[0049] In some preferred embodiments of the present application, the pH value of the calcium-based montmorillonite is 7.5-8.5, and specifically, for example, it can be 7.5, 7.8, 7.9, 8.0, 8.4, 8.5, and any value in the range constituted by any two of these point values.

[0050] According to the present application, in step 2), the solution B is added to solution A, which can be in any way as long as it can be added uniformly, and the preferred way is dropwise.

[0051] According to the present application, in step 2), the temperature during the aging is 60-80℃, and specifically, for example, it can be 60℃, 65℃, 70℃, 75℃, 78℃, 80℃, and any value in the range constituted by any two of these point values.

[0052] According to the present application, in step 2), the aging time can be selected in a wide range, such as 2-10h, preferably 3-8h, and specifically, for example, it can be 3h, 4h, 5h, 6h, 8h, and any value in the range constituted by any two of these point values.

[0053] According to the present application, in order to remove the moisture in the material and facilitate subsequent catalyst crushing, in step 2), the first drying temperature is 100-150℃, preferably 120℃.

[0054] According to the present application, in step 2), the crushing is to 180-200 mesh, and both too large and too small particle sizes are not suitable for the catalyst shaping of the present application and are not conducive to the formation of pore structure.

[0055] In some preferred embodiments of the present application, in step 1), the amount of the soluble salt of cobalt added is 2%-4% of the mass of the catalyst in terms of cobalt oxide, the amount of the soluble salt of lanthanide series metal added is 0.5%-1.5% of the mass of the catalyst in terms of its oxide, and the amount of the ammonium salt of molybdenum added is 6.5%-9.0% of the mass of the catalyst in terms of molybdenum oxide.

[0056] In some preferred embodiments of the present application, in step 3), the aluminum-containing compound is pseudo-boehmite.

[0057] In some preferred embodiments of the present application, in step 3), the mass ratio of the amount of magnesium oxide added to the amount of aluminum oxide added is 1:2.0-4.5.

[0058] According to the present invention, in step 3), the binder is an acid, such as at least one of citric acid, nitric acid and oxalic acid.

[0059] In some preferred embodiments of the present invention, the binder is citric acid, and the amount of the binder added is 3%-5% of the mass of the catalyst.

[0060] In some preferred embodiments of the present invention, in order to avoid affecting the pore structure of the catalyst, in step 3), the second drying is performed by natural drying at room temperature.

[0061] According to the present invention, in step 3), the catalyst can be extruded into different shapes, such as strips, as needed.

[0062] According to the present invention, in step 3), calcination is mainly for forming a stable catalyst support structure.

[0063] In some preferred embodiments of the present invention, the calcination time is 2-4 hours.

[0064] The second aspect of the present invention provides a sulfur-tolerant shift catalyst prepared by the above preparation method.

[0065] The raw materials used in the following examples and comparative examples are all commercially available products, and the amount of raw materials added is calculated based on the preparation of 100 g of catalyst.

[0066] Example 1

[0067] The preparation method of the sulfur-tolerant shift catalyst comprises the following steps:

[0068] 1) Dissolve 14 g of cobalt nitrate and 1.52 g of cerium nitrate in 150 mL of deionized water and heat to 75°C to form solution A. Dissolve 10.4 g of ammonium molybdate in 100 mL of deionized water and heat to 75°C to form solution B.

[0069] 2) Then, 24 g of calcium-based montmorillonite powder with a pH of 7.8 was added to solution A and stirred evenly. Solution B was added dropwise to solution A and continued to stir evenly. 53.1 g of tetrabutyl titanate was added and stirred evenly. The mixture was maintained at 75°C for aging for 6 h. After primary drying at 120°C, the mixture was pulverized to 180-200 mesh to obtain cobalt-molybdenum-cerium pillared montmorillonite containing the active ingredient and the additive.

[0070] 3) Add 55.3 g of pseudo-boehmite powder and 12 g of light magnesium oxide powder to the pillared montmorillonite powder, wherein the mass ratio of magnesium oxide to aluminum oxide is 1:3.2, mix well, add 35 mL of an aqueous solution containing 3 g of citric acid, knead evenly, extrude into strips, dry naturally, and calcine at 530°C for 4 h to obtain the finished sulfur-resistant shift catalyst.

[0071] Example 2

[0072] A method for preparing a sulfur-tolerant shift catalyst comprises the following steps:

[0073] 1) 10 g of cobalt nitrate and 0.95 g of cerium nitrate were dissolved in 140 mL of deionized water to obtain solution A, and 9.76 g of ammonium molybdate was dissolved in 120 mL of deionized water to obtain solution B, which were heated to 60°C;

[0074] 2) Then 20 g of calcium-based montmorillonite powder with a pH value of 7.5 was added to solution A and stirred uniformly, solution B was added dropwise to solution A, and stirring was continued to make it uniform, 63.7 g of tetrabutyl titanate was then added and stirred uniformly, the temperature was kept at 60°C for 8 h, and after the first drying at 120°C, the product was crushed to 180-200 mesh to obtain cobalt-molybdenum-cerium pillared montmorillonite containing active components and additives;

[0075] 3) 62.9 g of pseudoboehmite powder and 10 g of light magnesium oxide powder were added to the above pillared montmorillonite powder, the mass ratio of the added magnesium oxide and aluminum oxide was 1:4.4, and they were mixed uniformly, 40 mL of an aqueous solution containing 4 g of citric acid was added and kneaded uniformly, and then it was extruded into a strip shape, naturally air-dried, and calcined at 500°C for 4 h to obtain the finished sulfur-tolerant shift catalyst.

[0076] Example 3

[0077] A method for preparing a sulfur-tolerant shift catalyst comprises the following steps:

[0078] 1) 16 g of cobalt nitrate and 2.65 g of cerium nitrate were dissolved in 160 mL of deionized water to obtain solution A, and 7.9 g of ammonium molybdate was dissolved in 100 mL of deionized water to obtain solution B, which were heated to 78°C;

[0079] 2) Then 28 g of calcium-based montmorillonite powder with a pH value of 8.4 was added to solution A and stirred uniformly, solution B was added dropwise to solution A, and stirring was continued to make it uniform, 42.5 g of tetrabutyl titanate was then added and stirred uniformly, the temperature was kept at 78°C for 4 h, and after the first drying at 120°C, the product was crushed to 180-200 mesh to obtain cobalt-molybdenum-cerium pillared montmorillonite containing active components and additives;

[0080] 3) 70.2 g of aluminum gel powder and 15 g of light magnesium oxide powder were added to the above pillared montmorillonite powder, the mass ratio of the added magnesium oxide and aluminum oxide was 1:2.3, and they were mixed uniformly, 30 mL of an aqueous solution containing 5 g of citric acid was added and kneaded uniformly, and then it was extruded into a strip shape, naturally air-dried, and calcined at 550°C for 2 h to obtain the finished sulfur-tolerant shift catalyst.

[0081] Example 4

[0082] The preparation method of the sulfur-tolerant shift catalyst comprises the following steps:

[0083] 1) Dissolve 8 g of cobalt nitrate and 1.33 g of cerium nitrate in 120 mL of deionized water and heat to 80°C to form solution A. Dissolve 11.0 g of ammonium molybdate in 120 mL of deionized water and heat to 80°C to form solution B.

[0084] 2) Then, 30 g of calcium-based montmorillonite powder with a pH of 7.9 was added to solution A and stirred evenly. Solution B was added dropwise to solution A and continued to stir evenly. 38.3 g of tetrabutyl titanate was added and stirred evenly. The mixture was maintained at 80°C for aging for 3 h. After primary drying at 120°C, the mixture was pulverized to 180-200 mesh to obtain cobalt-molybdenum-cerium pillared montmorillonite containing the active ingredient and the additive.

[0085] 3) Add 54.7 g of pseudo-boehmite powder and 11 g of light magnesium oxide powder to the pillared montmorillonite powder, wherein the mass ratio of magnesium oxide to aluminum oxide is 1:3.5, mix well, add 40 mL of an aqueous solution containing 3.5 g of citric acid, knead evenly, extrude into strips, dry naturally, and calcine at 520°C for 3 h to obtain the finished sulfur-resistant shift catalyst.

[0086] Example 5

[0087] The preparation method of the sulfur-tolerant shift catalyst comprises the following steps:

[0088] 1) Dissolve 12.8 g of cobalt nitrate and 1.90 g of cerium nitrate in 140 mL of deionized water and heat to 70°C to form solution A. Dissolve 9.5 g of ammonium molybdate in 100 mL of deionized water and heat to 70°C to form solution B.

[0089] 2) Then, 25 g of calcium-based montmorillonite powder with a pH of 8.0 was added to solution A and stirred evenly. Solution B was added dropwise to solution A and continued to stir evenly. 34.0 g of tetrabutyl titanate was added and stirred evenly. The mixture was maintained at 70°C for aging for 5 h. After primary drying at 120°C, the mixture was pulverized to 180-200 mesh to obtain cobalt-molybdenum-cerium pillared montmorillonite containing the active ingredient and the additive.

[0090] 3) Add 58.6 g of pseudo-boehmite powder and 14 g of light magnesium oxide powder to the pillared montmorillonite powder, wherein the mass ratio of magnesium oxide to aluminum oxide is 1:2.9, mix well, add 45 mL of an aqueous solution containing 4.5 g of citric acid, knead evenly, extrude into strips, dry naturally, and calcine at 530°C for 3 h to obtain the finished sulfur-resistant shift catalyst.

[0091] Comparative Example 1

[0092] The preparation method of the sulfur-tolerant shift catalyst comprises the following steps:

[0093] 1) Dissolve 14 g of cobalt nitrate and 1.52 g of cerium nitrate in 150 mL of deionized water, heat to 75°C to obtain solution A, dissolve 10.4 g of ammonium molybdate in 100 mL of deionized water, heat to 75°C to form solution B;

[0094] 2) Then add 35 g of calcium-based montmorillonite powder with a pH value of 7.8 to solution A and stir until uniform, add solution B dropwise to solution A and continue to stir until uniform, maintain the temperature at 75°C and age for 6 h, after first drying at 120°C, crush to 180-200 mesh to obtain cobalt-molybdenum-cerium pillared montmorillonite containing active components and adjuvants;

[0095] 3) Add 43.4 g of pseudoboehmite powder and 9.3 g of light magnesium oxide powder to the above pillared montmorillonite powder, wherein the mass ratio of added magnesium oxide and aluminum oxide is 1:3.2, mix until uniform, add 35 mL of an aqueous solution containing 3 g of citric acid, knead until uniform, extrude into a strip shape, air dry, and calcine at 530°C for 4 h to obtain the finished sulfur-tolerant shift catalyst.

[0096] Comparative Example 2

[0097] A method for preparing a sulfur-tolerant shift catalyst, comprising the following steps:

[0098] 1) Dissolve 14 g of cobalt nitrate and 1.52 g of cerium nitrate in 150 mL of deionized water, heat to 75°C to obtain solution A, dissolve 10.4 g of ammonium molybdate in 100 mL of deionized water, heat to 75°C to form solution B;

[0099] 2) Then add 24 g of calcium-based montmorillonite powder with a pH value of 7.8 to solution A and stir until uniform, add solution B dropwise to solution A and continue to stir until uniform, maintain the temperature at 75°C and age for 6 h, after drying at 120°C, crush to 180-200 mesh to obtain cobalt-molybdenum-cerium pillared montmorillonite containing active components and adjuvants;

[0100] 3) Add 55.3 g of pseudoboehmite powder, 12 g of light magnesium oxide powder, and 12.5 g of titanium oxide powder to the above pillared montmorillonite powder, wherein the mass ratio of added magnesium oxide and aluminum oxide is 1:3.2, mix until uniform, add 35 mL of an aqueous solution containing 3 g of citric acid, knead until uniform, extrude into a strip shape, air dry, and calcine at 530°C for 4 h to obtain the finished sulfur-tolerant shift catalyst.

[0101] Comparative Example 3

[0102] 1) Dissolve 14 g of cobalt nitrate and 1.52 g of cerium nitrate in 150 mL of deionized water and heat to 75°C to form solution A. Dissolve 10.4 g of ammonium molybdate in 100 mL of deionized water and heat to 75°C to form solution B.

[0103] 2) Then, 24 g of sodium montmorillonite powder with a pH of 7.8 was added to solution A and stirred evenly. Solution B was added dropwise to solution A and continued to stir evenly. 53.1 g of tetrabutyl titanate was added and stirred evenly. The mixture was maintained at 75°C for aging for 6 h. After primary drying at 120°C, the mixture was pulverized to 180-200 mesh to obtain cobalt-molybdenum-cerium pillared montmorillonite containing the active ingredient and the additive.

[0104] 3) Add 55.3 g of pseudo-boehmite powder and 12 g of light magnesium oxide powder to the pillared montmorillonite powder, wherein the mass ratio of magnesium oxide to aluminum oxide is 1:3.2, mix well, add 35 mL of an aqueous solution containing 3 g of citric acid, knead evenly, extrude into strips, dry naturally, and calcine at 530°C for 4 h to obtain the finished sulfur-resistant shift catalyst.

[0105] Comparative Example 4

[0106] The preparation method of the sulfur-tolerant shift catalyst comprises the following steps:

[0107] 1) Dissolve 14 g of cobalt nitrate and 1.52 g of cerium nitrate in 150 mL of deionized water and heat to 75°C to form solution A. Dissolve 10.4 g of ammonium molybdate in 100 mL of deionized water and heat to 75°C to form solution B.

[0108] 2) Then, 24 g of calcium-based montmorillonite powder with a pH of 7.0 was added to solution A and stirred evenly. Solution B was added dropwise to solution A and continued to stir evenly. 53.1 g of tetrabutyl titanate was added and stirred evenly. The mixture was maintained at 75°C for aging for 6 h. After primary drying at 120°C, the mixture was pulverized to 180-200 mesh to obtain cobalt-molybdenum-cerium pillared montmorillonite containing the active ingredient and the additive.

[0109] 3) Add 55.3 g of pseudo-boehmite powder and 12 g of light magnesium oxide powder to the pillared montmorillonite powder, wherein the mass ratio of magnesium oxide to aluminum oxide is 1:3.2, mix well, add 35 mL of an aqueous solution containing 3 g of citric acid, knead evenly, extrude into strips, dry naturally, and calcine at 530°C for 4 h to obtain the finished sulfur-resistant shift catalyst.

[0110] Test Example 1

[0111] Physicochemical properties and pressurized activity tests of sulfur-tolerant shift catalysts:

[0112] use Figure 1The pressurized activity evaluation device and evaluation conditions shown were used to test the physicochemical properties and pressurized activity of the catalysts prepared in the above examples and comparative examples, Figure 1 The device in the above formula was used to simulate industrial conditions, determine the tail gas carbon monoxide concentration and its change of the "original particle size" catalyst under different conditions, compare the shift activity and stability of the catalyst, and comprehensively evaluate the performance of the catalyst. The reaction tube is a stainless steel tube with a thermocouple tube in the center. According to the requirement of different water-gas ratio, a certain amount of water is added, which is gasified at high temperature and enters the reaction tube with the raw material gas to carry out the water gas shift reaction, and the tail gas after reaction is analyzed by chromatography. The chromatograms of the tail gas after reaction of the sulfur-tolerant shift catalyst of Example 1 and the conventional sulfur-tolerant shift catalyst QCS-03 are shown in Figure 2 and Figure 3 , and the chromatography test results are shown in Table 2 and Table 3.

[0113] The specific evaluation conditions include:

[0114] The catalyst loading amount is 50 mL;

[0115] The sulfurization conditions of the sulfur-tolerant shift catalyst are as follows:

[0116] Sulfurization gas composition: CO content: 50.0%; H2S content: ~0.3%; balance: H2;

[0117] Pressure: 2.0 MPa; dry gas space velocity: 1000 h -1 ; H2S content: ~0.3%;

[0118] Sulfurize at 250℃ for 4h, heat to 300℃ for 3h, heat to 350℃ for 2h.

[0119] The pressurized evaluation conditions of the sulfur-tolerant shift catalyst are as follows:

[0120] Raw gas composition: CO content: 65.0%; H2S content: ~0.1%; balance: H2;

[0121] Inlet temperature: 250℃; pressure: 4.0 MPa; water / gas: 0.4;

[0122] Dry gas space velocity: 2000 h -1 ; Time: 20h;

[0123] The pressurized activity of the catalyst is the average value of the stable data, and the results are shown in Table 1.

[0124] The comparative sample is the conventional sulfur-tolerant catalyst QCS-03 (produced by Shandong Qilu Kelun Chemical Research Institute Co., Ltd.).

[0125] Table 1 Physicochemical properties and pressurized evaluation results of sulfur-tolerant shift catalyst

[0126] .

[0127] It can be seen from Table 1 that the physicochemical properties and pressurized activities of catalysts prepared with different ratios are different, especially the catalyst strength, specific surface area and outlet methane content are greatly affected.

[0128] The amount of calcium-based montmorillonite powder used in Comparative Example 1 was high, and the catalyst strength was significantly reduced; in Comparative Example 2, tetrabutyl titanate was not used, and the specific surface area was significantly reduced; in Comparative Example 3, sodium-based montmorillonite was used instead of calcium-based montmorillonite, which had a certain promoting effect on the methanation side reaction, resulting in an excessively high outlet CH4 content; the pH of the calcium-based montmorillonite in Comparative Example 4 was 7.0, and although the catalyst strength was increased, the specific surface area was reduced, which had a significant promoting effect on the methanation side reaction, and the outlet CH4 content was too high.

[0129] In particular, under the same conditions, the methane content at the outlet of the sulfur-resistant catalyst of the embodiment of the present invention is significantly lower than that of the conventional sulfur-resistant catalyst QCS-03 and the sulfur-resistant catalyst of the comparative example. The sulfur-resistant catalyst of the present invention can significantly reduce the methanation side reaction.

[0130] Table 2 The chromatographic test results of the tail gas after the reaction of the physicochemical properties and pressurized activity test of the sulfur-resistant catalyst in Example 1 of the present invention

[0131] .

[0132] Table 3. Physicochemical performance and pressure activity test results of conventional sulfur-resistant catalyst QCS-03 after reaction.

[0133] .

[0134] Comparison of the results in Tables 2 and 3 further shows that the methane content at the outlet of the sulfur-resistant catalyst of the embodiment of the present invention is significantly lower than that of the conventional sulfur-resistant catalyst QCS-03. The sulfur-resistant catalyst of the present invention can significantly reduce the methanation side reaction.

[0135] Test Example 2

[0136] Thermal conductivity test of sulfur-resistant catalyst:

[0137] The thermal conductivity of the sulfur-resistant catalyst was measured using a thermal conductivity meter (DRL-11). The specific process is as follows: First, read the reading on the scale before loading the sample, then remove the pressure plate, and apply a thin layer of thermal grease on the end faces of the upper and lower hot electrodes and the upper and lower surfaces of the sulfur-resistant catalyst sample; place the sample between the upper and lower hot electrodes for axis assembly, lower the reflective screen, and then tighten the screws on the pressure plate by mechanical force to make the sulfur-resistant catalyst sample in close contact with the upper and lower hot end surfaces, read the reading on the scale again, and subtract the reading on the scale before loading the sample from the reading on the scale to obtain the actual thickness of the sulfur-resistant catalyst sample; set the temperature of the external constant temperature water bath to 40℃±0.1℃, and turn on the circulation switch; turn on the host power switch, start the computer, and enter the DRL thermal conductivity test program. Set the temperature of the hot electrode and start heating: enter the cross-sectional area and thickness of the sulfur-resistant catalyst sample in the program, turn on the heating switch, and measure the thermal conductivity; by changing the temperature of the heater, the thermal conductivity of the sulfur-resistant catalyst sample is tested, and the results are shown in Table 4.

[0138] Table 4 Thermal conductivity of sulfur-resistant catalyst

[0139] .

[0140] The above performance test results show that compared with the comparative example and the existing conventional sulfur-resistant shift catalyst, the sulfur-resistant shift catalyst prepared in the embodiment of the present invention has a higher thermal conductivity and stronger mass and heat transfer capabilities.

[0141] The catalyst of the present invention disperses the active components between the montmorillonite layers to form a pillared montmorillonite structure. The interlayer structure allows reactants and products to pass more quickly, and the active metal is more conducive to the reaction heat generated by its reaction than the carrier, thereby improving the heat and mass transfer performance of the catalyst as a whole. In addition, the thermal conductivity of the catalyst is affected by the carrier, and different carriers have different catalyst thermal conductivity. What the present invention can do is, under the same carrier conditions, through technical means to maximize the thermal conductivity of the catalyst of the present invention.

[0142] Finally, it should be noted that the above embodiments are intended only to illustrate the technical solutions of the present invention and do not constitute a limitation of the present invention. Within the technical concept of the present invention, the technical solutions of the present invention may be subjected to various simple modifications, including combining the various technical features in any other appropriate manner. These simple modifications and combinations should also be considered as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A method for preparing a sulfur-tolerant shift catalyst, characterized in that: include: 1) dissolving a soluble salt of cobalt and a soluble salt of a lanthanide metal in a first solvent and heating the mixture to 60-80° C. to obtain solution A; dissolving an ammonium salt of molybdenum in a second solvent and heating the mixture to 60-80° C. to obtain solution B; 2) Calcium-based montmorillonite powder is then added to solution A and stirred evenly. Solution B is then added to solution A and stirred evenly. Tetrabutyl titanate is then added and stirred evenly. The mixture is matured at 60-80°C, dried at 100-150°C, and then pulverized to 180-200 mesh to obtain pillared montmorillonite containing the active ingredient and the additive. 3) adding aluminum-containing compound powder and magnesium oxide powder to the pillared montmorillonite powder, mixing uniformly, adding an appropriate amount of binder and kneading uniformly, extruding into a shape, performing a second drying, and calcining at 500-550° C. to obtain a sulfur-resistant shift catalyst; Wherein, in step 1), the amount of the soluble cobalt salt added is 1%-8% of the mass of the catalyst calculated as cobalt oxide, the amount of the soluble salt of the lanthanide metal added is 0.2%-4% of the mass of the catalyst calculated as its oxide; the amount of the ammonium salt of molybdenum added is 4%-12% of the mass of the catalyst calculated as molybdenum oxide; In step 2), the amount of calcium-montmorillonite added is 20%-30% of the mass of the catalyst; In step 3), the aluminum-containing compound powder is 30%-45% of the catalyst mass as calculated as aluminum oxide; the magnesium oxide is added in an amount of 10%-15% of the catalyst mass; In step 2), the pH of the calcium-montmorillonite is 7.5-8.

5.

2. The preparation method according to claim 1, characterized in that In step 1), the soluble salt of cobalt is nitrate and / or acetate.

3. The preparation method according to claim 1, characterized in that In step 1), the soluble salt of the lanthanide metal is nitrate.

4. The preparation method according to claim 1, characterized in that In step 1), the ammonium salt of molybdenum acid is ammonium molybdate.

5. The preparation method according to any one of claims 1 to 4, characterized in that In step 1), the amount of the soluble cobalt salt added is 2%-4% of the catalyst mass, calculated as cobalt oxide; the amount of the soluble salt of the lanthanide metal added is 0.5%-1.5% of the catalyst mass, calculated as its oxide; and the amount of the ammonium salt of molybdenum added is 6.5%-9.0% of the catalyst mass, calculated as molybdenum oxide.

6. The preparation method according to claim 1, characterized in that In step 3), the mass ratio of magnesium oxide to aluminum oxide added is 1:2.0-4.

5.

7. The preparation method according to claim 1, characterized in that The binder is citric acid, and the amount of the binder added is 3%-5% of the mass of the catalyst.

8. The preparation method according to claim 1, characterized in that The calcination time is 2-4 hours.

9. The sulfur-tolerant shift catalyst prepared according to the preparation method according to any one of claims 1 to 8.

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