A cobalt-molybdenum sulfur-tolerant CO shift catalyst and a preparation process thereof
By introducing an imine-linked dopamine-silsesquioxane-cerium coordination composite structure onto the surface of an alumina support, and synergistically regulating it with specific small organic molecules, the problems of occupied active centers and structural instability of cobalt-molybdenum catalysts in high CO and sulfur-containing environments were solved, thereby improving the catalyst's high efficiency, stability, and anti-poisoning performance.
Patent Information
- Application Number
- CN202610646138.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-05-12
- Publication Date
- 2026-06-23
AI Technical Summary
Existing cobalt-molybdenum catalysts are prone to competitive CO adsorption under high CO partial pressure and sulfur-containing environments, resulting in the occupation of active sites and a decrease in reaction efficiency. Furthermore, their structural stability is insufficient in high-temperature and sulfur-containing environments, making it difficult to maintain excellent catalytic performance under complex operating conditions.
By introducing an imine-linked dopamine-silsesquioxane-cerium coordination composite structure onto the surface of an alumina support, a dynamic covalent network and a metal coordination network are constructed. Furthermore, 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine is used to regulate the electronic structure of the metal active center. Simultaneously, alkaline auxiliaries, electronic regulation auxiliaries, and dispersing auxiliaries are employed for synergistic effects, enabling multi-scale regulation of the dispersion state of the active components, interfacial bonding, and the reaction microenvironment.
It significantly improves the catalyst's activity stability and anti-poisoning performance under high CO and sulfur conditions, maintains high reactivity and long-term stability, and demonstrates superior overall performance compared to existing technologies.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of catalytic materials technology, specifically to a cobalt-molybdenum based CO sulfur-resistant conversion catalyst and its preparation process. Background Technology
[0002] In industrial processes such as coal-to-hydrogen, natural gas reforming, and refining tail gas treatment, the carbon monoxide shift reaction of sulfur-containing syngas is a key step in improving hydrogen yield and reducing CO content. Since feedstock gases commonly contain sulfides such as hydrogen sulfide, traditional iron-chromium shift catalysts are prone to sulfur poisoning and deactivation. Therefore, cobalt-molybdenum based catalysts, which have strong sulfur resistance, are increasingly being used. These catalysts typically use cobalt and molybdenum sulfides as the active phase, achieving the water-gas shift reaction by forming dispersed active centers on the support surface.
[0003] However, existing cobalt-molybdenum catalysts still have significant shortcomings under high CO partial pressure and complex sulfur-containing atmospheres. On the one hand, CO molecules have a strong competitive adsorption effect on active sites, which easily leads to the occupation of active centers and thus reduces reaction efficiency. On the other hand, cobalt-molybdenum sulfides are prone to migration and aggregation during the reaction, resulting in a decrease in the dispersion of the active phase. In addition, the interfacial bonding force between the support and the active components is insufficient, and the structure is prone to loosening or even deactivation under long-term high temperature and sulfur-containing environments.
[0004] To address these issues, existing technologies often employ optimization methods such as additive doping, support modification, or surface coating. However, most of these methods rely on single-mechanism control and struggle to simultaneously improve the stability of active sites, resistance to CO poisoning, and sulfur tolerance. Especially under complex operating conditions, the lack of tunability and multi-scale stabilization mechanisms in catalyst structures limits their further application.
[0005] Therefore, there is an urgent need to develop a cobalt-molybdenum based sulfur-resistant shift catalyst with a novel structural regulation method. By constructing a stable and tunable composite structure system, the electronic structure and interface structure of the active site can be synergistically regulated, thereby maintaining excellent catalytic performance and long-term stability in high CO and sulfur-containing environments. Summary of the Invention
[0006] To overcome the problems in the aforementioned technologies, such as catalysts' susceptibility to CO competitive adsorption leading to decreased activity, active component agglomeration and deactivation, and insufficient interfacial structural stability under high CO partial pressure and sulfur-containing environments, the present invention aims to provide a cobalt-molybdenum based CO sulfur-resistant shift catalyst and its preparation process. This invention introduces an imine-linked dopamine-silsesquioxane-cerium coordination composite structure onto the surface of an alumina support, constructing an organic-inorganic composite regulatory system with the synergistic effects of a dynamic covalent network, a metal coordination network, and a cage-like confined structure. Furthermore, it combines this with 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine to regulate the electronic structure of the metal active center. Simultaneously, the synergistic effects of alkaline promoters, electronic regulation promoters, and dispersing promoters enable multi-scale regulation of the dispersion state of the active components, interfacial bonding forces, and the reaction microenvironment. This invention significantly improves the catalyst's activity stability and anti-poisoning performance under high CO and sulfur-containing conditions.
[0007] The objective of this invention can be achieved through the following technical solutions: A cobalt-molybdenum based CO sulfur-resistant conversion catalyst, the catalyst comprising the following raw materials in parts by weight: 5-20 parts cobalt nitrate, 10-40 parts ammonium molybdate, 60-150 parts alumina, 5-30 parts an imine-linked dopamine-silsesquioxane-cerium coordination composite structure, 1-8 parts 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine, 1-5 parts alkaline auxiliaries, 1-5 parts electronic regulation auxiliaries, and 0.1-2 parts dispersing auxiliaries; the imine-linked dopamine-silsesquioxane-cerium coordination composite structure is an organic-inorganic composite structure formed by the condensation reaction of 2,5-dihydroxyterephthalaldehyde and dopamine to form an imine bond network, which is further crosslinked with octa(3-aminopropyl)silsesquioxane, and simultaneously constructed by the coordination of polyphenolic hydroxyl groups with cerium ions under the action of cerium nitrate.
[0008] Optionally, the imine-linked dopamine-silsesquioxane-cerium coordination complex comprises the following raw materials in parts by weight: 10-40 parts of 2,5-dihydroxyterephthalaldehyde, 5-25 parts of dopamine, 2-15 parts of octa(3-aminopropyl)silsesquioxane, 1-10 parts of cerium nitrate, and 30-100 parts of deionized water.
[0009] Optionally, the preparation method of the imine-linked dopamine-silsesquioxane-cerium coordination composite structure includes the following steps: (1) 2,5-Dihydroxyterephthalaldehyde and dopamine were added to deionized water to react and obtain a pre-reaction system containing an imine bond structure; (2) Add octa(3-aminopropyl)silsesquioxane to the pre-reaction system to carry out the reaction and obtain an organic-inorganic composite network system; (3) Add cerium nitrate to the organic-inorganic composite network system to react and obtain the imine-linked dopamine-silsesquioxane-cerium coordination composite structure.
[0010] Optionally, the reaction conditions in step (1) are: reaction temperature of 25-35℃, reaction time of 40-80 min, stirring speed of 200-500 rpm, and pH of the reaction system of 6.0-7.5.
[0011] Optionally, the reaction conditions in step (2) are: reaction temperature of 30-55℃, reaction time of 60-100 min, stirring speed of 300-600 rpm, and pH of the reaction system of 7.0-8.5.
[0012] Optionally, the reaction conditions in step (3) are: reaction temperature of 25-45℃, reaction time of 50-110 min, stirring speed of 200-500 rpm, and pH of the reaction system of 5.0-7.0.
[0013] Optionally, the alkaline additive is a mixture of magnesium oxide and potassium carbonate in a mass ratio of (1-3):(1-2); the electronic control additive is a mixture of titanium dioxide and zirconium oxide in a mass ratio of (1-2):(1-2); and the dispersing additive is a mixture of graphene quantum dots and polyvinylpyrrolidone in a mass ratio of (1):(2-5).
[0014] Optionally, a method for preparing a cobalt-molybdenum based CO sulfur-resistant shift catalyst includes the following steps: S1, cobalt nitrate and ammonium molybdate are mixed and dissolved in deionized water to obtain a metal precursor solution; S2, Alumina is added to the metal precursor solution for impregnation treatment, and an imine-linked dopamine-silsesquioxane-cerium coordination complex and 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine are added. At the same time, alkaline additives, electronic control additives and dispersing additives are added, and the mixture is mixed, dispersed and aged to obtain the precursor slurry. S3. After drying the precursor slurry, it is then calcined and sulfided to obtain the cobalt-molybdenum CO sulfur-resistant conversion catalyst.
[0015] Optionally, the reaction conditions for step S1 are: reaction temperature of 25–40°C, reaction time of 30–90 min, and stirring speed of 200–500 rpm; the reaction conditions for step S2 are: impregnation temperature of 40–80°C, aging time of 2–6 h, stirring speed of 300–600 rpm, and pH of the reaction system of 6.5–8.5.
[0016] Optionally, the reaction conditions for step S3 are as follows: drying temperature of 80–120°C, drying time of 6–12 h, calcination temperature of 350–500°C, calcination time of 2–5 h, and sulfidation temperature of 300–400°C, sulfidation time of 3–8 h.
[0017] The beneficial effects of this invention are: This invention constructs an imine-linked dopamine-silsesquioxane-cerium coordination composite structure, achieving synergistic coupling of dynamic covalent networks, polyphenol-metal coordination, and cage-like siloxane confinement effects. This allows the cobalt-molybdenum active components to form a stable and highly dispersed nanoscale structure on the support surface, effectively suppressing particle migration and sintering under high temperature and sulfur-containing environments. Simultaneously, the introduced 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine, through its polyhydroxyl groups and π-conjugated structure, regulates the electron cloud density of the metal center, reducing the strong adsorption of CO molecules and promoting the conversion of reaction intermediates. Furthermore, the coordination layer formed by dopamine and cerium ions further enhances interfacial bonding and constructs a stable sulfur-resistant barrier structure. This, combined with alkaline promoters regulating the reaction microenvironment and electronic modulation promoters optimizing electron transfer pathways, enables the catalyst to maintain high conversion reaction activity and long-term operational stability under high CO and high sulfur conditions, demonstrating a significant improvement in overall performance compared to existing technologies. Attached Figure Description
[0018] The invention will now be further described with reference to the accompanying drawings.
[0019] Figure 1 Comparison of infrared spectra of a physical mixture of 2,5-dihydroxyterephthalaldehyde and dopamine and a dopamine-silsesquioxane-cerium coordination complex structure linked by an imine bond. Detailed Implementation
[0020] The present invention will be further described below with reference to specific embodiments. However, the present invention is not limited to the following embodiments. Equivalent adjustments made without departing from the spirit and essence of the present invention should also be considered to fall within the protection scope of the present invention.
[0021] Example 1: The purpose of this example is to verify the basic feasibility of catalyst construction under low component content and mild conditions.
[0022] S1, 10 parts of 2,5-dihydroxyterephthalaldehyde and 5 parts of dopamine were added to 30 parts of deionized water and stirred at 200 rpm for 40 min at 25 °C to allow a condensation reaction to form a pre-reaction system containing an imine bond structure; then 2 parts of octa(3-aminopropyl)silsesquioxane were added and reacted at 30 °C for 60 min; then 1 part of cerium nitrate was added and reacted at 25 °C for 50 min to obtain an imine bond-linked dopamine-silsesquioxane-cerium coordination composite structure; S2, 5 parts of cobalt nitrate and 10 parts of ammonium molybdate were added to deionized water and stirred at 200 rpm for 30 min at 25°C to obtain a metal precursor solution; 60 parts of alumina were added to the solution for impregnation treatment, and 5 parts of the composite structure obtained in step S1 and 1 part of 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine were added. At the same time, 1 part of an alkaline auxiliary agent composed of magnesium oxide and potassium carbonate, 1 part of an electronic regulation auxiliary agent composed of titanium dioxide and zirconium oxide, and 0.1 part of a dispersing auxiliary agent composed of graphene quantum dots and polyvinylpyrrolidone were added. The solution was aged at 40°C for 2 h. S3. The obtained precursor slurry was dried at 80℃ for 6 h, calcined at 350℃ for 2 h, and then sulfided at 300℃ for 3 h to obtain the target catalyst.
[0023] Example 2: The purpose of this example is to obtain a cobalt-molybdenum based CO sulfur-resistant conversion catalyst with optimal overall performance.
[0024] S1, 25 parts of 2,5-dihydroxyterephthalaldehyde and 15 parts of dopamine were added to 65 parts of deionized water and stirred at 350 rpm for 60 min at 30 °C to form a stable imine bond structure; then 8 parts of octa(3-aminopropyl)silsesquioxane were added and reacted at 40 °C for 80 min; then 5 parts of cerium nitrate were added and reacted at 35 °C for 80 min to obtain a structurally stable imine bond-linked dopamine-silsesquioxane-cerium coordination composite structure. Figure 1 Before modification, it was a mixture of 2,5-dihydroxyterephthalaldehyde and dopamine, at 1670 cm⁻¹ -1 A distinct C=O absorption peak for the aldehyde group appears nearby, and also between 3300 and 3500 cm⁻¹. -1 Strong hydroxyl and amino absorption peaks are present within the range; after modification, it is a dopamine-silsesquioxane-cerium coordinated organic-inorganic composite structure with imine bonds, and the original C=O peak is significantly weakened or even disappeared, while at 1620 cm⁻¹... -1 The appearance of a new C=N characteristic peak nearby indicates successful imine bond formation; the broadening and decreased intensity of the hydroxyl peak indicate its participation in coordination; at 1100 cm⁻¹ -1 The absorption peaks of Si–O–Si in the vicinity are significantly enhanced, and at 600 cm⁻¹ -1 The presence of Ce–O characteristic peaks nearby further confirms the successful construction of the composite structure; S2, 12 parts of cobalt nitrate and 25 parts of ammonium molybdate were added to deionized water and stirred at 350 rpm for 60 min at 30°C to obtain a homogeneous metal precursor solution; 100 parts of alumina were added for impregnation, and 15 parts of the composite structure obtained in step S1 and 4 parts of 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine were added, along with 3 parts of alkaline additive, 3 parts of electronic regulation additive and 1 part of dispersant additive, and aged at 60°C for 4 h; S3. The obtained slurry was dried at 100℃ for 10 h, calcined at 420℃ for 4 h, and then sulfided at 350℃ for 6 h to obtain a catalyst with the best comprehensive performance.
[0025] Example 3: The purpose of this example is to investigate the structural stability of the catalyst under high component content and enhanced conditions.
[0026] S1, 40 parts of 2,5-dihydroxyterephthalaldehyde and 25 parts of dopamine were added to 100 parts of deionized water and stirred at 500 rpm for 80 min at 35°C to fully form an imine bond network; then 15 parts of octa(3-aminopropyl)silsesquioxane were added and reacted at 55°C for 100 min; then 10 parts of cerium nitrate were added and reacted at 45°C for 110 min to obtain a highly cross-linked composite structure. S2, 20 parts of cobalt nitrate and 40 parts of ammonium molybdate were added to deionized water and stirred at 500 rpm for 90 min at 40°C to obtain a metal precursor solution; 150 parts of alumina were added for impregnation, and 30 parts of the composite structure obtained in step S1 and 8 parts of 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine were added, along with 5 parts of alkaline additive, 5 parts of electronic regulation additive and 2 parts of dispersant additive, and aged at 80°C for 6 h; S3. The obtained slurry was dried at 120℃ for 12 h, calcined at 500℃ for 5 h, and then sulfided at 400℃ for 8 h to obtain the target catalyst.
[0027] Comparative Example 1: The purpose of this comparative example is to verify the effect of the lack of imine bond network and silsesquioxane confined structure on catalyst performance.
[0028] S1, 15 parts of dopamine were added to 65 parts of deionized water and stirred at 350 rpm for 60 min at 30 °C; then 5 parts of cerium nitrate were added and reacted at 35 °C for 80 min to obtain the dopamine-cerium coordination structure. S2, 12 parts of cobalt nitrate and 25 parts of ammonium molybdate were added to deionized water and stirred at 350 rpm for 60 min at 30°C to obtain a homogeneous metal precursor solution; 100 parts of alumina were added for impregnation, and 15 parts of the coordination structure obtained in step S1 and 4 parts of 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine were added, along with 3 parts of alkaline additive, 3 parts of electronic regulation additive and 1 part of dispersant additive, and aged at 60°C for 4 h; S3. The obtained slurry was dried at 100℃ for 10 h, calcined at 420℃ for 4 h, and then sulfided at 350℃ for 6 h to obtain the catalyst.
[0029] Comparative Example 2: The purpose of this comparative example is to verify the effect of the lack of metal coordination and cage-like confinement structure on the structural stability of the catalyst.
[0030] S1, 25 parts of 2,5-dihydroxyterephthalaldehyde and 15 parts of dopamine were added to 65 parts of deionized water and stirred at 350 rpm for 60 min at 30°C to form an imine bond structure. S2, 12 parts of cobalt nitrate and 25 parts of ammonium molybdate were added to deionized water and stirred at 350 rpm for 60 min at 30°C to obtain a homogeneous metal precursor solution; 100 parts of alumina were added for impregnation, and 15 parts of the imine structure obtained in step S1 and 4 parts of 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine were added, along with 3 parts of alkaline additive, 3 parts of electronic regulation additive and 1 part of dispersant additive, and aged at 60°C for 4 h; S3. The obtained slurry was dried at 100℃ for 10 h, calcined at 420℃ for 4 h, and then sulfided at 350℃ for 6 h to obtain the catalyst.
[0031] Comparative Example 3: The purpose of this comparative example is to verify the influence of small organic molecules on the regulation of the electronic structure of metals and their resistance to CO poisoning.
[0032] S1, 25 parts of 2,5-dihydroxyterephthalaldehyde and 15 parts of dopamine were added to 65 parts of deionized water and stirred at 350 rpm for 60 min at 30 °C to form a stable imine bond structure; then 8 parts of octa(3-aminopropyl)silsesquioxane were added and reacted at 40 °C for 80 min; then 5 parts of cerium nitrate were added and reacted at 35 °C for 80 min to obtain an imine bond-linked dopamine-silsesquioxane-cerium coordination composite structure. S2, 12 parts of cobalt nitrate and 25 parts of ammonium molybdate were added to deionized water and stirred at 350 rpm for 60 min at 30°C to obtain a uniform metal precursor solution; 100 parts of alumina were added for impregnation, and 15 parts of the composite structure obtained in step S1 were added, along with 3 parts of alkaline additive, 3 parts of electronic regulation additive and 1 part of dispersant additive, and aged at 60°C for 4 h. S3. The obtained slurry was dried at 100℃ for 10 h, calcined at 420℃ for 4 h, and then sulfided at 350℃ for 6 h to obtain the catalyst.
[0033] Performance testing: 1. CO conversion reaction activity testing method The catalysts prepared in the examples and comparative examples were tableted, crushed, and sieved to 20 to 40 mesh. 2 mL of the catalyst was weighed and packed into a stainless steel fixed-bed reactor with an inner diameter of 10 mm. Pretreatment was performed under a nitrogen atmosphere, with the temperature increased to 350 °C at a rate of 5 °C per min and maintained for 2 h. Subsequently, a simulated synthesis gas system was introduced, containing 10% carbon monoxide, 10% water vapor, 500 ppm hydrogen sulfide, and the remainder nitrogen. The total gas flow rate was 150 mL per min, and the space velocity was 3000 h⁻¹. After stabilizing the reaction at 350 °C for 2 h, samples were taken. The carbon monoxide concentration in the inlet and outlet gases was detected using an online gas chromatograph, and the carbon monoxide conversion rate was calculated to evaluate the catalyst's conversion reaction activity.
[0034] 2. Test methods for resistance to CO poisoning Under the same reaction apparatus and pretreatment conditions as described above, the volume fraction of carbon monoxide in the feed gas was increased to 30%, while the remaining components remained unchanged. The reactor was continuously operated at 350 °C for 8 h, and the carbon monoxide conversion rate was measured every 1 h. The initial conversion rate and the conversion rate after 8 h were recorded, and the activity retention rate was calculated as the ratio of the 8 h conversion rate to the initial conversion rate multiplied by 100% to evaluate the catalyst's resistance to poisoning under high carbon monoxide partial pressure conditions.
[0035] 3. Test method for sulfur resistance stability Under fixed-bed reaction conditions, the hydrogen sulfide concentration in the feed gas was increased to 2000 ppm, the carbon monoxide volume fraction was 10%, the water vapor volume fraction was 10%, and the remainder was nitrogen. The reaction was continuously operated for 24 h at 350 ℃ and a space velocity of 3000 h⁻¹. The carbon monoxide conversion rate was measured every 2 h, and the initial conversion rate and the final conversion rate were recorded. The activity decay rate was calculated as the initial conversion rate minus the final conversion rate divided by the initial conversion rate multiplied by 100%. The average conversion rate from 20 to 24 h was also recorded to evaluate the stability of the catalyst in a high-sulfur environment.
[0036] 4. Cyclic life and structural stability testing methods The catalyst was subjected to a cyclic test at 350 °C. Each cycle included a reaction stage and a regeneration stage. The reaction stage involved introducing a gas with a volume fraction of 10% carbon monoxide, 10% water vapor, 500 ppm hydrogen sulfide, and the remainder nitrogen, and running for 8 h. The regeneration stage involved introducing nitrogen at a flow rate of 100 mL per min and purging at 350 °C for 2 h. A total of 10 cycles were performed. The carbon monoxide conversion rate at the end of each cycle was recorded, and the cycle stability coefficient was calculated as the ratio of the conversion rate of the 10th cycle to the conversion rate of the 1st cycle multiplied by 100% to evaluate the cyclic stability of the catalyst.
[0037] Table 1 Catalyst performance test results As shown in Table 1, the examples and comparative examples showed significant differences in all performance indicators. The overall performance of the examples was significantly better than that of the comparative examples, and Example 2 achieved the highest value in all indicators, indicating that the synergistic structural system constructed by the present invention has a significant effect on improving catalyst performance.
[0038] In terms of CO conversion reactivity, the CO conversion rates of Examples 1 to 3 were 86.3%, 94.8%, and 90.6%, respectively, significantly higher than those of the comparative examples, with Example 2 exhibiting the highest conversion rate. This indicates that the imine-linked dopamine-silsesquioxane-cerium coordination complex structure can effectively improve the dispersion of the active component and enhance the reactivity, while the comparative examples showed lower utilization efficiency of the active center due to the lack of a complete synergistic structure.
[0039] In terms of resistance to CO poisoning, the activity retention rates of all examples were above 82%, with Example 2 reaching 91.7%, significantly better than the comparative example. This indicates that 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine has a significant regulatory effect on the electronic structure of metals, which can weaken the strong adsorption of CO molecules and improve the stability of the catalyst under high CO partial pressure conditions. In contrast, the performance of Comparative Example 3, which lacks this small organic molecule, is significantly reduced.
[0040] Based on the results of the sulfur resistance stability test, the examples still maintained a high final conversion rate under high sulfur conditions, with Example 2 reaching 90.5%, while the comparative example showed a significant decrease. This indicates that the dopamine-cerium coordination structure can form a stable sulfur-resistant interface layer, while the confinement effect provided by silsesquioxane effectively inhibits the loss of active components and structural damage.
[0041] In terms of cycle stability, the examples maintained high activity after multiple cycles, and the cycle stability coefficient of Example 2 reached 92.8%, which was much higher than that of the comparative example. This indicates that the constructed dynamic covalent network and coordination structure have good structural recovery ability and anti-deactivation ability, while the comparative example showed significant activity decay during the cycle due to its simple structure.
[0042] In summary, this invention achieves a comprehensive improvement in catalyst activity, CO poisoning resistance, sulfur resistance, and recyclability by constructing an imine-linked dopamine-silsesquioxane-cerium coordination composite structure and introducing specific small organic molecules for synergistic regulation, which is significantly superior to the prior art.
Claims
1. A cobalt-molybdenum based CO sulfur-resistant shift catalyst, characterized in that, The catalyst comprises the following raw materials in parts by weight: 5-20 parts cobalt nitrate, 10-40 parts ammonium molybdate, 60-150 parts alumina, 5-30 parts an imine-linked dopamine-silsesquioxane-cerium coordination composite structure, 1-8 parts 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine, 1-5 parts alkaline auxiliaries, 1-5 parts electronic regulation auxiliaries, and 0.1-2 parts dispersing auxiliaries. The imine-linked dopamine-silsesquioxane-cerium coordination composite structure is an organic-inorganic composite structure formed by the condensation reaction of 2,5-dihydroxyterephthalaldehyde and dopamine to form an imine bond network, which is further crosslinked with octa(3-aminopropyl)silsesquioxane, and simultaneously constructed by the coordination of polyphenolic hydroxyl groups with cerium ions under the action of cerium nitrate.
2. The cobalt-molybdenum based CO sulfur-resistant shift catalyst according to claim 1, characterized in that, The imine-linked dopamine-silsesquioxane-cerium coordination composite structure comprises the following raw materials in parts by weight: 10-40 parts of 2,5-dihydroxyterephthalaldehyde, 5-25 parts of dopamine, 2-15 parts of octa(3-aminopropyl)silsesquioxane, 1-10 parts of cerium nitrate, and 30-100 parts of deionized water.
3. A cobalt-molybdenum based CO sulfur-resistant shift catalyst according to claim 1 or 2, characterized in that, The preparation method of the imine-linked dopamine-silsesquioxane-cerium coordination composite structure includes the following steps: (1) 2,5-Dihydroxyterephthalaldehyde and dopamine were added to deionized water to react and obtain a pre-reaction system containing an imine bond structure; (2) Add octa(3-aminopropyl)silsesquioxane to the pre-reaction system to carry out the reaction and obtain an organic-inorganic composite network system; (3) Add cerium nitrate to the organic-inorganic composite network system to react and obtain the imine-linked dopamine-silsesquioxane-cerium coordination composite structure.
4. The cobalt-molybdenum based CO sulfur-resistant shift catalyst according to claim 3, characterized in that, The reaction conditions for step (1) are: reaction temperature of 25-35℃, reaction time of 40-80 min, stirring speed of 200-500 rpm, and pH of the reaction system of 6.0-7.
5.
5. The cobalt-molybdenum based CO sulfur-resistant shift catalyst according to claim 3, characterized in that, The reaction conditions for step (2) are: reaction temperature of 30-55℃, reaction time of 60-100 min, stirring speed of 300-600 rpm, and pH of the reaction system of 7.0-8.
5.
6. The cobalt-molybdenum based CO sulfur-resistant shift catalyst according to claim 3, characterized in that, The reaction conditions for step (3) are: reaction temperature of 25-45℃, reaction time of 50-110 min, stirring speed of 200-500 rpm, and pH of the reaction system of 5.0-7.
0.
7. The cobalt-molybdenum based CO sulfur-resistant shift catalyst according to claim 1, characterized in that, The alkaline additive is a mixture of magnesium oxide and potassium carbonate in a mass ratio of (1-3):(1-2); the electronic regulation additive is a mixture of titanium dioxide and zirconium oxide in a mass ratio of (1-2):(1-2); and the dispersing additive is a mixture of graphene quantum dots and polyvinylpyrrolidone in a mass ratio of (1):(2-5).
8. A method for preparing a cobalt-molybdenum based CO sulfur-resistant shift catalyst, characterized in that, The preparation method includes the following steps: S1, cobalt nitrate and ammonium molybdate are mixed and dissolved in deionized water to obtain a metal precursor solution; S2, Alumina is added to the metal precursor solution for impregnation treatment, and an imine-linked dopamine-silsesquioxane-cerium coordination complex and 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine are added. At the same time, alkaline additives, electronic control additives and dispersing additives are added, and the mixture is mixed, dispersed and aged to obtain the precursor slurry. S3. After drying the precursor slurry, it is then calcined and sulfided to obtain the cobalt-molybdenum CO sulfur-resistant conversion catalyst.
9. The preparation method of a cobalt-molybdenum based CO sulfur-resistant shift catalyst according to claim 8, characterized in that, The reaction conditions for step S1 are: reaction temperature of 25–40°C, reaction time of 30–90 min, and stirring speed of 200–500 rpm; the reaction conditions for step S2 are: immersion temperature of 40–80°C, aging time of 2–6 h, stirring speed of 300–600 rpm, and pH of the reaction system of 6.5–8.
5.
10. The preparation method of a cobalt-molybdenum based CO sulfur-resistant shift catalyst according to claim 8, characterized in that, The reaction conditions for step S3 are as follows: drying temperature of 80-120℃, drying time of 6-12 h, calcination temperature of 350-500℃, calcination time of 2-5 h, and sulfidation temperature of 300-400℃, sulfidation time of 3-8 h.