Preparation method of nickel-based hydrogenation catalyst

Abstract

This invention belongs to the field of catalyst technology, specifically relating to a method for preparing a nickel-based hydrogenation catalyst. A nickel source solution, a support, an aluminum source solution, and a precipitant undergo a co-precipitation reaction, followed by aging, water washing, and filtration to obtain a nickel-based catalyst filter cake. The nickel-based catalyst filter cake is then mixed with n-butanol to obtain a turbid liquid. A 1,10-phenanthroline coordination solution is added to the turbid liquid and stirred, followed by the addition of a polydimethylsiloxane solution and continued stirring to obtain a mixed solution. The mixed solution is then heated for extraction and dehydration, followed by rotary evaporation, heat treatment, and reduction to obtain the nickel-based hydrogenation catalyst. This invention constructs a protective layer on the catalyst surface and creates a hierarchical porous structure through n-butanol volatilization and the interweaving of a flexible PDMS network, achieving dual optimization of packing density and performance. The resulting nickel-based hydrogenation catalyst exhibits both selectivity and stability.

Description

Technical Field

[0001] This invention belongs to the field of catalyst technology, specifically relating to a method for preparing a hydrogenated nickel-based catalyst. Background Technology

[0002] Petroleum resins are low-molecular-weight (200-3000) thermoplastic polymers produced from C5-C9 fractions, a byproduct of petroleum cracking, through polymerization and other processes. They possess good water and acid / alkali resistance and are widely used in coatings, rubber additives, paper additives, inks, and adhesives. However, untreated petroleum resins contain a complex variety of unsaturated groups (such as alkenyl and aryl groups) and impurities (such as halides and sulfides), which directly affect the resin's properties (photothermal stability, softening point, viscosity, color, etc.). The color of the resin is closely related to the conjugated unsaturated bonds present in the polymer, especially the indene structure, while the odor emitted by the resin when heated is related to sulfides. Unrefined petroleum resins have defects that make them difficult to directly apply to the production of downstream high-value-added products. Industrial production typically employs modification methods to improve resin quality, and hydrogenation is the most direct and effective method for modifying petroleum resins.

[0003] Catalytic hydrogenation is the simplest and most effective refining method for modifying petroleum resins. Using a suitable catalyst, catalytic hydrogenation of the resin can effectively reduce unsaturated carbon-carbon double bonds in the resin's structural units, improving its stability. Hydrogenation treatment of petroleum resins can also reduce the content of heteroatoms such as halogens and sulfur, and destroy color-developing units in the resin, improving its adhesion and color properties.

[0004] The hydrogenation reaction of petroleum resins requires the action of a suitable catalyst, which can effectively catalyze the hydrogenation process and improve the color and stability of the product. However, this field still faces some technical challenges, such as low catalyst hydrogenation efficiency, difficulties in the diffusion and adsorption of resin molecules in the catalyst channels, and harsh hydrogenation reaction conditions.

[0005] In recent years, researchers have made significant progress in the composition, geometry, and electronic structure of the active metal components of catalysts, as well as in the design of support morphology and pore structure. The following are key research directions:

[0006] Design of metal active sites: The dispersion, distribution, and valence state regulation of metal active sites are key factors affecting catalyst performance. For example, by optimizing the composition and valence state of the metal active component, the hydrogenation efficiency of the catalyst can be improved.

[0007] Synergistic effects of composite metals: Studies have found that synergistic effects between composite metals can significantly improve catalyst performance. For example, some bimetallic catalysts enhance the adsorption and hydrogenation capacity of petroleum resin molecules through intermetallic interactions.

[0008] Support design: The morphology and pore structure of the support also have a significant impact on the performance of the catalyst. By designing a suitable support pore structure, the diffusion performance of resin molecules in the catalyst channels can be improved, thereby increasing the hydrogenation efficiency.

[0009] Significant progress has been made in the research of petroleum resin hydrogenation catalysts in improving hydrogenation efficiency, catalyst performance and reducing costs, but continuous innovation is still needed to meet the needs of industrial production.

[0010] Traditional nickel-based catalysts (such as Ni / SiO2) have limited industrial applications due to the following drawbacks:

[0011] 1. High bulk density (>0.5g / cm³) 3 This leads to high reactor packing density and low mass transfer efficiency, especially in fluidized bed or slurry bed processes where energy consumption increases significantly.

[0012] 2. Easily oxidized and deactivated: Nickel particles are easily converted into inert NiO in oxidizing atmospheres (such as CO2 and water vapor), resulting in loss of activity.

[0013] 3. Carbon buildup and sintering: Coke is easily generated during hydrocarbon reactions, which blocks the pores. Nickel particles agglomerate and sinter at high temperatures.

[0014] 4. Difficulty in achieving both selectivity and stability: Traditional modification methods often sacrifice activity to improve selectivity. For example, sulfided nickel-based catalysts exhibit significant selectivity in hydrogenation reactions, as they can more effectively and selectively adsorb and convert target reactants, reducing side reactions. However, sulfided nickel-based catalysts may face insufficient stability under certain reaction conditions, especially in high-temperature or strong acid / alkali environments.

[0015] Existing improvement methods (such as mesoporous supports and additive doping) have partially improved catalytic performance, but it is difficult to achieve both ultra-low packing density and multifunctional surface protection at the same time.

[0016] Chinese patent CN109876812A discloses a method for preparing a nickel-based hydrogenation catalyst, comprising the following steps: Step 1: Dissolve a soluble nickel salt in deionized water to prepare a first solution; dissolve a precipitant in deionized water to prepare a second solution; dilute silica sol with deionized water to prepare a silica sol solution; Step 2: Stir the silica sol solution prepared in Step 1, and simultaneously add the first and second solutions prepared in Step 1 to the silica sol solution; Step 3: Heat the silica sol solution prepared in Step 2 to 90-110℃ to evaporate water, and simultaneously stir it to precipitate nickel-loaded silica sol; Step 4: Wash the nickel-loaded silica sol precipitate with deionized water until the free anion content is less than 0.03% (w / w), and then dry and calcine it sequentially to obtain a catalyst precursor; Step 5: Reduce the catalyst precursor prepared in Step 4 to obtain the hydrogenation catalyst. This patent simply evaporates the water in the system by heating, which leads to a reduction in hydrophilic groups on the surface of the dehydrated particles and an increase in interparticle attraction (such as van der Waals forces and capillary forces), causing the particles to pack more tightly. Ultimately, this not only affects the dispersion of Ni in the system, but also leads to a greater packing density of the final product. As a result, the dispersion is uneven when using a slurry bed reaction, affecting the catalytic activity. Summary of the Invention

[0017] The purpose of this invention is to provide a method for preparing a hydrogenated nickel-based catalyst. A protective layer is constructed on the catalyst surface, and a hierarchical porous structure is constructed by pore creation through n-butanol volatilization and interweaving of a PDMS flexible network, thereby achieving dual optimization of packing density and performance. The resulting hydrogenated nickel-based catalyst has both selectivity and catalyst stability.

[0018] The preparation method of the hydrogenated nickel-based catalyst of the present invention includes the following steps:

[0019] (1) The nickel source solution, support, aluminum source solution and precipitant undergo a co-precipitation reaction, followed by aging, water washing and filtration to obtain a nickel-based catalyst filter cake;

[0020] (2) The nickel-based catalyst filter cake was mixed with n-butanol to obtain a turbid liquid;

[0021] (3) Add 1,10-phenanthroline coordination solution to the turbid liquid and stir to react, then add polydimethylsiloxane solution and continue stirring to obtain a mixed solution;

[0022] (4) The mixed solution was heated and extracted for dehydration, then subjected to rotary evaporation, heat treatment, and reduction to obtain a hydrogenated nickel-based catalyst.

[0023] In step (1), the nickel source in the nickel source solution is one of nickel nitrate, nickel chloride or nickel sulfate, and the concentration of the nickel source solution is 0.5-1.5 mol / L.

[0024] In step (1), the carrier is a silica sol or a sodium silicate solution. The silica sol is a neutral silica sol, and the concentration of the sodium silicate solution is 0.22-0.25 mol / L. The aluminum source solution is aluminum nitrate or sodium aluminate, and the concentration of the aluminum source solution is 0.02-0.03 mol / L.

[0025] In step (1), the precipitant is a sodium carbonate solution with a concentration of 1-1.5 mol / L, and the volume ratio of the nickel source solution, the carrier, the aluminum source solution and the precipitant is 1:1:1:1-1.5.

[0026] In step (1), the coprecipitation reaction temperature is 40-90℃, the coprecipitation reaction time is 20-120min, the aging temperature is 60-80℃, and the aging time is 1-2 hours.

[0027] The nickel-based catalyst filter cake obtained in step (1) is a wet nickel-based catalyst filter cake that has not been dried.

[0028] In step (2), the mass ratio of nickel-based catalyst filter cake to n-butanol is 1:1-3, which can ensure pore-forming and dispersion efficiency.

[0029] In step (2), the stirring speed is 400-800 r / min and the stirring time is 10-60 min.

[0030] The method for preparing the 1,10-phenanthroline coordination solution in step (3) is to mix 1,10-phenanthroline with n-butanol and disperse it by ultrasonication to obtain the 1,10-phenanthroline coordination solution; wherein the mass ratio of 1,10-phenanthroline to n-butanol is 1:14-23.

[0031] In step (3), the mass ratio of 1,10-phenanthroline to nickel-based catalyst filter cake in the 1,10-phenanthroline coordination solution is 0.4-2.7:1.

[0032] In step (3), the stirring reaction temperature is 40-70℃ and the stirring reaction time is 1-3h.

[0033] The method for preparing the polydimethylsiloxane solution in step (3) is to stir and mix polydimethylsiloxane with n-butanol to obtain a polydimethylsiloxane solution; wherein the mass ratio of polydimethylsiloxane to n-butanol is 1:20-30.

[0034] In step (3), the mass of polydimethylsiloxane in the polydimethylsiloxane solution is 3-10% of the mass of the nickel-based catalyst filter cake.

[0035] In step (3), the stirring temperature is 50-70℃ and the stirring time is 0.5-2h.

[0036] The heating temperature in step (4) is 115-135℃.

[0037] In step (4), the heat treatment temperature is 200-300℃, the heat treatment time is 2-5h, and the heat treatment atmosphere is nitrogen atmosphere.

[0038] In step (4), the reduction temperature is 300-400℃, the reduction time is 2-5 hours, and the reduction atmosphere is hydrogen atmosphere.

[0039] The application of the nickel-based hydrogenation catalyst prepared in this invention in selective hydrogenation reactions is as follows:

[0040] Applicable systems: Selective hydrogenation of olefins (C=C bonds) and benzene rings in C9 petroleum resins, with olefin selectivity ≥98% and aromatic ring hydrogenation rate <5%.

[0041] Anti-toxicity performance: After continuous operation for 30-40 hours in sulfur-containing (sulfur content of 50-200ppm) or acidic media, the activity retention rate is >90%.

[0042] This invention introduces n-butanol, 1,10-phenanthroline, and polydimethylsiloxane into a nickel-based catalyst filter cake. Through extraction by heating at 115-135°C, n-butanol preferentially volatilizes, forming 5-20 nm mesopores. During heat treatment at 200-300°C, polydimethylsiloxane partially pyrolyzes, and the molecules stack together to form 0.1-1 μm macropores. The 5-20 nm mesopores and 0.1-1 μm macropores ultimately form a hierarchical pore structure.

[0043] Weak coordination of n-butanol: The hydroxyl group of n-butanol reacts with Ni 2+ It forms dynamic coordination bonds, inhibits nickel particle aggregation, and regulates the electronic environment of nickel centers.

[0044] Strong coordination of 1,10-phenanthroline: 1,10-phenanthroline and Ni 2+ A stable [Ni(phen)3] is formed. 2+ Complexes precisely modulate the d-band center of nickel, enhancing selective adsorption.

[0045] The flexible network constructed from PDMS provides mechanical support and a hydrophobic barrier while allowing selective permeation of H2 molecules. The main chain of PDMS consists of alternating silicon (Si) and oxygen (O) atoms, with hydrophobic methyl groups (-CH3) as side chains. The nonpolar nature of the methyl groups creates weak van der Waals forces between the PDMS surface and water molecules, resulting in a larger water contact angle and significant hydrophobicity. H2 molecules are extremely small (approximately 0.29 nm in diameter), while the free-volume pores (approximately 1-2 nm) in the PDMS cross-linked network allow small molecules to pass through.

[0046] The present invention requires controlling the size of metallic nickel nanoparticles in the hydrogenated nickel-based catalyst to be between 5-20 nm in order to maintain activity.

[0047] This invention utilizes the synergistic effect of a ternary organic compound consisting of n-butanol, polydimethylsiloxane (PDMS), and 1,10-phenanthroline to prepare a product with an ultra-low bulk density (0.2-0.3 g / cm³). 3 It features a multifunctional protective surface and a highly selective hydrogenated nickel-based catalyst, which exhibits significantly enhanced stability and selectivity in high-temperature and high-sulfur environments.

[0048] This invention has the following advantages:

[0049] 1. Ultra-low bulk density improves mass transfer efficiency

[0050] In traditional catalytic systems, excessively high catalyst packing density has long been a challenge. High packing density results in low internal porosity, leading to significant resistance to reactant molecule diffusion within the catalyst particles. Taking a common organic hydrogenation reaction as an example, reactants need to diffuse from the bulk gas or liquid phase to the catalyst surface and then further to the active sites within the catalyst. In this process, excessively high packing density severely hinders the diffusion rate of reactants, preventing the active sites from being fully utilized and drastically reducing catalytic efficiency.

[0051] This invention ingeniously combines the pore-forming effect of n-butanol with the flexible network properties of PDMS. During catalyst preparation, the thermal volatilization of n-butanol forms 5-20 nm mesopores within the catalyst, which become the initial channels for mass transport. The flexible network formed by PDMS interweaves between these pores, continuously stacking to form macropores of 0.1-1 μm, further optimizing the pore structure. This unique structure allows for a significant reduction in the catalyst's packing density to 0.2-0.3 g / cm³. 3 Under the new structure, reactant molecules can diffuse more smoothly inside the catalyst and quickly reach the active sites, greatly improving mass transfer efficiency. At the same time, it significantly reduces the risk of active sites being masked by other substances, providing a strong guarantee for the efficient conduction of catalytic reactions.

[0052] 2. Diverse protective functions

[0053] Currently, most catalyst protective layers on the market have relatively limited functions, often only protecting against a single failure mechanism. For example, some protective layers only possess hydrophobic properties, preventing water molecules from damaging the catalyst's active sites; while others only serve to prevent carbon buildup, mitigating deactivation caused by carbon accumulation on the catalyst surface to some extent. However, actual industrial catalytic environments are complex and variable, and a single protective function is far from sufficient to meet the demands.

[0054] This invention utilizes a ligand complex formed by 1,10-phenanthroline and nickel, combined with PDMS, to form a mesh-shaped hydrophobic surface layer, i.e., a protective layer. The siloxane chains (-Si-O-Si-) of PDMS form a hydrophobic framework, while the aromatic rings of 1,10-phenanthroline are embedded in the PDMS network through π-π stacking, synergistically enhancing surface hydrophobicity. The hydrophobic surface layer effectively blocks polar molecules (such as H2O and H2S) while allowing nonpolar H2 molecules to permeate, balancing hydrophobicity and reactivity. n-Butanol, as a polar solvent, promotes the uniform dispersion of 1,10-phenanthroline in the PDMS matrix; additionally, n-butanol also acts as a dispersant to disperse the nickel-based catalyst filter cake, promoting subsequent reactions. The hydrophobic surface layer effectively blocks the intrusion of water molecules and various polar poisons, preventing them from reacting with active sites and causing catalyst deactivation. Simultaneously, during the catalytic reaction, temperature fluctuations generate thermal stress, posing a significant challenge to the structural stability of the catalyst. The protective layer of this invention can buffer this thermal stress. The protective layer has a porous structure, and the pores act as a "stress buffer." When the temperature fluctuates, the micro-deformation of the pore walls can accommodate volume changes, reducing overall stress and preventing stress concentration at the interface, thereby preventing the catalyst from collapsing due to thermal shock. Furthermore, the protective layer can firmly fix the nickel active sites, inhibiting their sintering and loss during the reaction process.

[0055] The protective layer has a unique selective permeability, which protects the active sites from interference by harmful external substances while allowing small molecule reactants (such as hydrogen) to pass through freely. This ensures that the catalyst still has long-lasting stability under highly selective conditions and greatly extends the service life of the catalyst.

[0056] 3. Combination of selectivity and stability

[0057] In this invention, 1,10-phenanthroline and n-butanol have a synergistic effect. Besides its pore-forming function, n-butanol, being polar, can act as a solvent for dissolving 1,10-phenanthroline, while simultaneously increasing the polarity of the reaction system. Mixing n-butanol with the nickel-based catalyst filter cake helps improve the solubility of both 1,10-phenanthroline and nickel ions, promoting their interaction. The polar environment enhances the electrostatic attraction between the metal ions and the 1,10-phenanthroline ligand, thus facilitating complex formation. n-Butanol can also participate in the reaction as an auxiliary ligand. The hydroxyl (-OH) group in the n-butanol molecule, containing a lone pair of electrons, exhibits a certain coordinating ability. When n-butanol reacts with Ni… 2+ During the reaction, the lone pair electrons of the -OH group can fill Ni. 2+ The empty orbitals of the ligands form coordinate σ bonds (a weak coordination interaction). During this process, the ligands (the -OH group of n-butanol) coordinate towards Ni through these bonds. 2+Providing lone pairs of electrons increases the electron cloud density around nickel ions, reducing the Lewis acidity of nickel. The strong coordination of 1,10-phenanthroline provides structural stability, while the weak coordination of n-butanol allows for dynamic reconstruction of active sites. Together, they achieve a balance between high catalyst activity and long lifetime.

[0058] The beneficial effects of this invention are as follows:

[0059] 1. Synergistic optimization of ultra-low bulk density and efficient mass transfer

[0060] Existing technology drawbacks: Traditional nickel-based catalysts have a bulk density >0.5 g / cm³, resulting in low porosity, high mass transfer resistance, and high energy consumption.

[0061] This invention constructs a hierarchical porous structure (5-20 nm mesopores and 0.1-1 μm macropores) by using n-butanol volatilization to create pores and interweaving a flexible PDMS network, reducing the packing density to 0.2-0.3 g / cm³. 3 It increases porosity by 2-3 times, improves reactant diffusion rate by more than 40%, and significantly enhances the utilization rate of active sites, making it suitable for low-energy-consumption processes such as slurry beds.

[0062] 2. Multifunctional protective layer achieves long-term stability

[0063] Existing technology limitations: Traditional protective layers have limited functionality (only hydrophobic or anti-carbon deposit), and cannot cope with oxidation, sintering, and thermal stress problems in complex industrial environments.

[0064] In this invention, 1,10-phenanthroline, nickel, and PDMS combine to form a hydrophobic surface layer, blocking water molecules and polar poisons from corroding the catalyst and enhancing its chemical inertness. The PDMS backbone consists of silicon-oxygen bonds (-Si-O-Si-), with hydrophobic methyl groups (-CH3) as side chains. The low surface energy of the methyl groups makes PDMS naturally hydrophobic, effectively repelling polar molecules (such as water and H2S). PDMS forms a continuous three-dimensional cross-linked network covering the catalyst surface, blocking the permeation pathway of water molecules. 1,10-phenanthroline coordinates with nickel ions to form a stable [Ni(phen)3] 2+ The complex is embedded in the PDMS network through π-π stacking and hydrogen bonding. The hydrophobic aromatic ring of 1,10-phenanthroline further reduces the surface energy and enhances the repulsion of polar poisons.

[0065] Selective penetration: Allows H2 to penetrate freely but blocks large molecular impurities, achieving "precision protection". The gaps between PDMS networks are about 1-2 nm, which is much larger than the size of H2 molecules (about 0.29 nm), allowing H2 to diffuse freely; the gaps between PDMS networks can also effectively prevent large molecular impurities in resin raw materials from contacting the active sites.

[0066] 3. Highly selective hydrogenation and precise control of active sites

[0067] Existing technology limitations: For C9 resins with large molecular weights (300-3000) and containing polycyclic aromatic hydrocarbons and structures with significant steric hindrance (such as dicyclopentadiene derivatives), the microporous structure of traditional sulfidation catalysts (such as Co-Mo / Al2O3) is insufficient to accommodate these large molecules, resulting in low mass transfer efficiency and insufficient utilization of active sites. Furthermore, sulfidation catalysts have limited ability to distinguish between different double bond types, failing to effectively differentiate between conjugated double bonds on the benzene ring and isolated olefins. This easily leads to over-hydrogenation, causing a decrease in the resin softening point (from 120℃ to 90℃) and a reduction in yield (only 70-80%). Traditional catalysts cannot perform effective selective hydrogenation and cannot differentiate hydrogenation based on complex functional groups.

[0068] This invention introduces n-butanol as a solvent to effectively dissolve 1,10-phenanthroline, thereby promoting the reaction of 1,10-phenanthroline with nickel ions (Ni... 2+ This process forms a complex and enhances the structural stability of the complex, thereby improving the catalytic efficiency and stability of the product.

[0069] Olefin selectivity ≥98%: preferential activation of C=C bonds, inhibiting excessive hydrogenation of aromatic rings.

[0070] Improved resistance to carbon buildup: The hydrophobic surface layer reduces the adsorption of coke precursors, resulting in a carbon buildup reduction of more than 60% compared to Ni / SiO2.

[0071] 4. Green technology and cost advantages

[0072] Existing technology drawbacks: Traditional modification relies on precious metal additives (such as Pt and Pd) or complex post-processing, which is costly.

[0073] In this invention, n-butanol can be recycled and reused, reducing raw material costs by more than 30%.

[0074] One-step construction of the protective layer: This invention utilizes 1,10-phenanthroline and nickel ions (Ni 2+ The complex formed by the process combines with PDMS to construct a protective layer in one step, requiring no additional processes and reducing energy consumption by more than 25%. Attached Figure Description

[0075] Figure 1 This is an electron microscope image of the hydrogenated nickel-based catalyst prepared in Example 1. Detailed Implementation

[0076] The present invention will be further described below with reference to embodiments.

[0077] Example 1

[0078] (1) Mix 200 ml of 0.5 mol / L nickel chloride solution, 200 ml of 0.225 mol / L sodium silicate solution and 200 ml of 0.026 mol / L sodium aluminate solution evenly, and slowly add 200 ml of 1.18 mol / L sodium carbonate solution under stirring to carry out co-precipitation reaction at 40℃ for 120 min, age at 60℃ for 2 h, wash with water, filter, and obtain nickel-based catalyst filter cake;

[0079] (2) 20g of nickel-based catalyst filter cake was mixed with 60g of n-butanol at 400r / min for 60min to obtain a turbid liquid;

[0080] (3) Add 189g of 1,10-phenanthroline coordination solution to the turbid liquid and stir at 40℃ and 300r / min for 3h. Then add 21g of polydimethylsiloxane solution and stir at 50℃ for 2h to obtain a mixed solution. The 1,10-phenanthroline coordination solution is prepared by mixing 9g of 1,10-phenanthroline with 180g of n-butanol and dispersing by ultrasonication. The polydimethylsiloxane solution is prepared by mixing 1g of polydimethylsiloxane with 20g of n-butanol.

[0081] (4) The mixed solution was heated to 115℃ for extraction and dehydration, then vacuumed to -0.1MPa at 60℃ for rotary evaporation, heat-treated at 200℃ for 5h under nitrogen atmosphere, and reduced with hydrogen at 300℃ for 5h to obtain the nickel-based hydrogenated catalyst. The electron micrograph of the nickel-based hydrogenated catalyst is shown in [image missing]. Figure 1 .

[0082] The bulk density of the hydrogenated nickel-based catalyst was measured to be 0.21 g / cm³. 3 With a contact angle θ of 112°, this catalyst possesses good lightweight bulk density and hydrophobic properties. In C9 petroleum resin solution, it exhibits good suspension and can more fully contact and react with the reactants.

[0083] Catalyst lifetime testing showed that the initial hydrogenation rate of the hydrogenated nickel-based catalyst reached 96.2%, and the hydrogenation rate remained at 93.1% after 10 applications. Colorimetric testing showed that the hydrogenated resin solution had a colorimetric score of 0.

[0084] The C9 petroleum resin solution (before hydrogenation) and the resin solution after hydrogenation were analyzed by nuclear magnetic resonance (NMR) to compare the changes in olefin and aromatic bonds before and after hydrogenation. The original content of olefin bonds was 17.1% before hydrogenation, which decreased to 1.02% after hydrogenation; the original content of aromatic bonds was 27.9% before hydrogenation, which decreased to 15.13% after hydrogenation. This meets the requirement of hydrogenating as many olefin bonds as possible while preserving aromatic bonds during the hydrogenation of C9 resin.

[0085] Example 2

[0086] (1) Mix 200 ml of 1.5 mol / L nickel nitrate solution, 200 ml of 0.25 mol / L sodium silicate solution and 200 ml of 0.03 mol / L sodium aluminate solution evenly, and slowly add 220 ml of 1.5 mol / L sodium carbonate solution under stirring to carry out co-precipitation reaction at 90℃ for 30 min, age at 80℃ for 1 h, wash with water, filter, and obtain nickel-based catalyst filter cake;

[0087] (2) 10g of nickel-based catalyst filter cake was mixed with 20g of n-butanol at 600r / min for 30min to obtain a turbid liquid;

[0088] (3) Add 427g of 1,10-phenanthroline coordination solution to the turbid liquid and stir at 50℃ and 350r / min for 2h. Then add 8.7g of polydimethylsiloxane solution and stir at 60℃ for 0.5h to obtain a mixed solution. The 1,10-phenanthroline coordination solution is prepared by mixing 27g of 1,10-phenanthroline with 400g of n-butanol and dispersing by ultrasonication. The polydimethylsiloxane solution is prepared by mixing 0.3g of polydimethylsiloxane with 8.4g of n-butanol.

[0089] (4) The mixed solution was heated at 135°C for extraction and dehydration, then vacuumed at 60°C to -0.1 MPa for rotary evaporation, heat-treated at 300°C for 2 hours under nitrogen atmosphere, and reduced with hydrogen at 350°C for 4 hours to obtain the hydrogenated nickel-based catalyst.

[0090] The bulk density of the hydrogenated nickel-based catalyst was measured to be 0.19 g / cm³. 3 With a contact angle θ of 108°, this catalyst possesses good lightweight bulk density and hydrophobic properties. In C9 petroleum resin solution, it exhibits good suspension and can more fully contact and react with the reactants.

[0091] Catalyst lifetime testing showed that the initial hydrogenation rate of the hydrogenated nickel-based catalyst reached 95.8%, and the hydrogenation rate remained at 92.8% after 10 applications. Colorimetric testing showed that the hydrogenated resin solution had a color rating of 0.

[0092] Example 3

[0093] (1) Mix 200 ml of 1 mol / L nickel nitrate solution, 200 ml of 30% neutral silica sol and 200 ml of 0.02 mol / L sodium aluminate solution evenly, and slowly add 300 ml of 1 mol / L sodium carbonate solution under stirring to carry out co-precipitation reaction at 60℃ for 20 min, age at 70℃ for 1.5 h, wash with water, filter, and obtain nickel-based catalyst filter cake;

[0094] (2) 20g of nickel-based catalyst filter cake was mixed with 20g of n-butanol at 800r / min for 10min to obtain a turbid liquid;

[0095] (3) Add 428g of 1,10-phenanthroline coordination solution to the turbid liquid and stir at 70℃ and 400r / min for 1h. Then add 62g of polydimethylsiloxane solution and continue stirring at 70℃ for 1h to obtain a mixed solution. The 1,10-phenanthroline coordination solution is prepared by mixing 18g of 1,10-phenanthroline with 410g of n-butanol and dispersing by ultrasonication. The polydimethylsiloxane solution is prepared by mixing 2g of polydimethylsiloxane with 60g of n-butanol.

[0096] (4) The mixed solution was heated at 120°C for extraction and dehydration, vacuumed at 60°C to -0.1MPa for rotary evaporation, heat-treated at 250°C for 3 hours under nitrogen atmosphere, and reduced with hydrogen at 400°C for 2 hours to obtain the hydrogenated nickel-based catalyst.

[0097] The bulk density of the hydrogenated nickel-based catalyst was measured to be 0.2 g / cm³. 3 With a contact angle θ of 115°, this catalyst possesses good lightweight bulk density and hydrophobic properties. In C9 petroleum resin solution, it exhibits good suspension and can more fully contact and react with the reactants.

[0098] Catalyst lifetime testing showed that the initial hydrogenation rate of the hydrogenated nickel-based catalyst reached 97.1%, and the hydrogenation rate remained at 94% after 10 applications. Colorimetric testing showed that the hydrogenated resin solution had a color rating of 0.

[0099] Comparative Example 1

[0100] (1) Step (1) is the same as in Example 1;

[0101] (2) The nickel-based catalyst filter cake was dried at 120°C for 4 hours, ground to 200 mesh, placed in a muffle furnace and calcined at 350°C for 3 hours, and then reduced at 400°C for 3 hours under a hydrogen atmosphere to obtain the hydrogenated nickel-based catalyst.

[0102] The bulk density of the hydrogenated nickel-based catalyst was measured to be 0.55 g / cm³. 3 Because the nickel-based catalyst filter cake was not treated with 1,10-phenanthroline coordination solution, polydimethylsiloxane solution, and n-butanol, particle sintering occurred in its pores, leading to a significant increase in packing density. The water contact angle θ of the hydrogenated nickel-based catalyst was 68°, indicating that the catalyst surface is rich in hydroxyl groups and has strong hydrophilicity.

[0103] In catalyst lifetime testing, the catalyst powder immediately sank to the bottom of the reactor upon being poured in, forming a sediment layer. Even after stirring at the required reaction speed, some particles remained suspended, resulting in uneven dispersion and agglomeration. The high bulk density led to rapid catalyst settling, making uniform dispersion difficult to achieve with mechanical stirring alone, resulting in low solid-liquid mass transfer efficiency and affecting reaction activity. The initial hydrogenation rate of the nickel-based hydrogenation catalyst was 61.37%, decreasing to 43.2% after the second application and further to 23.7% after the third application. Sulfur impurities in the C9 petroleum resin were directly adsorbed onto the active sites of nickel, causing irreversible poisoning and rapid catalyst deactivation. The nickel-based hydrogenation catalyst prepared in Comparative Example 1 exhibited poor hydrogenation performance; its activity was significantly affected in a high-sulfur environment (75 ppm sulfur content in the C9 petroleum resin solution).

[0104] Comparative Example 2

[0105] Replace n-butanol with an equal mass of deionized water, and follow the same steps as in Example 1.

[0106] The final obtained nickel-hydrogenated catalyst was found to be grayish-black in color; its bulk density was 0.62 g / cm³. 3 The contact angle θ is 87°.

[0107] After catalyst lifetime testing, the initial hydrogenation rate of the hydrogenated nickel-based catalyst was only 18%, and the resin solution after hydrogenation was brown.

[0108] In Comparative Example 2, the use of water as a solvent disrupted the chemical equilibrium of the siloxane coating, causing the coating layer to change from a flexible hydrophobic membrane to a rigid non-porous gel. This resulted in the nickel particles being encapsulated to form amorphous agglomerates, ultimately leading to over-coating of the catalyst, which failed to exhibit active centers and became inactive.

[0109] Comparative Example 3

[0110] Without adding 1,10-phenanthroline coordination solution, the other steps are the same as in Example 1.

[0111] The bulk density of the hydrogenated nickel-based catalyst was measured to be 0.41 g / cm³. 3 The contact angle θ is 88°.

[0112] Catalyst lifetime testing showed that the initial hydrogenation rate of the hydrogenated nickel-based catalyst was 86.89%, and the hydrogenation rate remained at 75.7% after 10 applications. Colorimetric testing showed that the hydrogenated resin solution had a colorimetric score of 1.

[0113] Nuclear magnetic resonance (NMR) analysis was performed on C9 petroleum resin solutions (before hydrogenation) and after hydrogenation to compare the changes in olefin and aromatic bonds. The original olefin bond content was 17.3%, which decreased to 2.3% after hydrogenation; the original aromatic bond content was 28.2%, which decreased to 3.7% after hydrogenation. Given the specific requirements for selective hydrogenation of C9 petroleum resin, the hydrogenation process should aim to hydrogenate olefin bonds as much as possible while preserving aromatic bonds. NMR comparison revealed that this catalyst cannot achieve selective hydrogenation of C9 petroleum resin; it can only indiscriminately hydrogenate the unsaturated bonds in the resin.

[0114] Comparative Example 4

[0115] Without adding polydimethylsiloxane solution, the other steps are the same as in Example 1.

[0116] The bulk density of the hydrogenated nickel-based catalyst was measured to be 0.45 g / cm³. 3 The contact angle θ is 70°.

[0117] Catalyst lifetime testing showed that the initial hydrogenation rate of the hydrogenated nickel-based catalyst was 63.5%, which decreased to 31.1% after three applications. Colorimetric testing showed that the hydrogenated resin solution had a colorimetric rating of 3.

[0118] In Comparative Example 4, the absence of polydimethylsiloxane solution resulted in the lack of a hydrophobic barrier on the catalyst surface, directly exposing the nickel active sites to the reaction medium. Sulfur impurities in the C9 petroleum resin (such as benzothiophene) directly formed strong bonds with the nickel active centers, leading to sulfur poisoning. Furthermore, the prolonged high-temperature stirring reaction caused the catalyst, lacking a hydrophobic barrier, to break down due to collision and shearing, resulting in pore structure collapse and a significantly reduced catalyst lifetime.

[0119] Catalytic performance test:

[0120] The catalytic activity of the catalyst was tested using the hydrogenation reaction of C9 petroleum resin under the following reaction conditions:

[0121] Reaction pressure: 5MPa

[0122] Reaction temperature: 240℃

[0123] Stirring speed of the reactor: 600 r / min

[0124] Reactor volume: 100ml

[0125] C9 petroleum resin solution dosage: 40g

[0126] C9 petroleum resin solution mass concentration: 25% (solvent is D40)

[0127] Sulfur content in C9 petroleum resin solution: 75 ppm

[0128] Catalyst dosage: 0.1g.

[0129] 0.1 g of hydrogenated nickel-based catalyst and 40 g of C9 petroleum resin solution were added to a hydrogenation reactor. After displacing the air in the reactor, hydrogen gas was introduced, and the pressure was increased to 5 MPa. A reaction temperature program was set, raising the temperature from room temperature to 240°C over 1 hour. The reaction was maintained at 240°C for 1 hour, after which heating was stopped. A stirring program was set, maintaining a stirring speed of 600 r / min throughout the heating and reaction processes for a total of 2 hours. Stirring was stopped after the reaction was completed. After the reactor cooled to room temperature, the remaining pressure was released through the air vent valve. The reactor was opened, and the hydrogenated resin solution was removed. The bromine value was measured to obtain the hydrogenation rate, which was compared with the bromine value of the C9 petroleum resin solution (before hydrogenation). The bromine value was determined according to the method for determining the bromine value of petroleum resins in GB / T24138—2009.

[0130] Hydrogenation rate:

[0131] Hydrogenation rate = (bromine value before hydrogenation - bromine value after hydrogenation) / bromine value before hydrogenation.

[0132] Colorimetric test:

[0133] The color of the hydrogenated resin solution was measured using a petroleum product colorimeter (SS-1) manufactured by Shanghai Pengpu Refrigeration Co., Ltd.

[0134] Catalyst lifetime test:

[0135] The catalyst lifespan was determined using the above-described C9 petroleum resin hydrogenation reaction. After the reaction, the hydrogenated nickel-based catalyst was separated from the hydrogenated resin solution by centrifugation. The hydrogenated nickel-based catalyst was then placed back into the reactor, and fresh C9 petroleum resin solution was added. After sealing, hydrogen gas was introduced, and the hydrogenation reaction was carried out again. The hydrogenated nickel-based catalyst was reused repeatedly, and the hydrogenation rate of each hydrogenation reaction was calculated and recorded after ten reuses.

[0136] Bulk density:

[0137] The catalyst powder sample was dried at 105℃ for two hours to remove adsorbed water, cooled, and then placed in a desiccator for later use. A funnel was placed above a graduated cylinder, and the catalyst powder was slowly poured into the cylinder until the powder exceeded the graduation mark. The graduated cylinder was then placed on a vibrating table and vibrated at a frequency of 200 times per minute for 5 minutes until the volume no longer changed. The bulk density of the catalyst (g / cm³) was calculated. 3 = m / V. Repeat the operation three times and take the average value.

[0138] Hydrophobicity test:

[0139] The water contact angle measurement method characterizes the hydrophobic properties of a material surface by measuring the contact angle of water on the surface. When the contact angle θ > 90°, the surface is hydrophobic; the larger θ is, the stronger the hydrophobicity.

[0140] The catalyst powder was dried at 105℃ for two hours, cooled, and 0.5-1g was weighed and placed in a tablet press mold. The tablets were then pressed at 10MPa for 3 minutes to produce smooth, round tablets. The tablets must be free of cracks and loose particles.

[0141] Fix the tablet onto the sample stage of the measuring instrument and adjust the lens focus until the surface is clearly visible. Use a microsyringe to slowly add 1-2 μL of deionized water 1-2 mm above the tablet surface to form a complete droplet. Calculate the contact angle θ using the lying-drop method, taking measurements at 5 different locations for each tablet and averaging the results.

Claims

1. A method for preparing a nickel-based hydrogenation catalyst, characterized in that... Includes the following steps: (1) The nickel source solution, support, aluminum source solution and precipitant undergo a co-precipitation reaction, followed by aging, water washing and filtration to obtain a nickel-based catalyst filter cake; (2) The nickel-based catalyst filter cake was mixed with n-butanol to obtain a turbid liquid; (3) Add 1,10-phenanthroline coordination solution to the turbid liquid and stir to react, then add polydimethylsiloxane solution and continue stirring to obtain a mixed solution; (4) The mixed solution was heated, extracted and dehydrated, rotary evaporated, heat-treated and reduced to obtain a hydrogenated nickel-based catalyst; In step (1), the aluminum source in the aluminum source solution is aluminum nitrate or sodium aluminate, and the carrier is silica sol or sodium silicate solution. The silica sol is neutral silica sol.

2. The method for preparing the nickel-based hydrogenation catalyst according to claim 1, characterized in that... In step (1), the nickel source solution is one of nickel nitrate, nickel chloride, or nickel sulfate, and the concentration of the nickel source solution is 0.5-1.5 mol / L; the concentration of the sodium silicate solution is 0.22-0.25 mol / L; the concentration of the aluminum source solution is 0.02-0.03 mol / L; the precipitant is sodium carbonate solution, and the concentration of the sodium carbonate solution is 1-1.5 mol / L. The volume ratio of the nickel source solution, the carrier, the aluminum source solution, and the precipitant is 1:1:1:1-1.

5.

3. The method for preparing the nickel-based hydrogenation catalyst according to claim 1, characterized in that... In step (1), the coprecipitation reaction temperature is 40-90℃, the coprecipitation reaction time is 20-120min, the aging temperature is 60-80℃, and the aging time is 1-2 hours.

4. The method for preparing the nickel-based hydrogenation catalyst according to claim 1, characterized in that... In step (2), the mass ratio of nickel-based catalyst filter cake to n-butanol is 1:1-3; the stirring speed is 400-800 r / min; and the stirring time is 10-60 min.

5. The method for preparing the nickel-based hydrogenation catalyst according to claim 1, characterized in that... The method for preparing the 1,10-phenanthroline coordination solution in step (3) is to mix 1,10-phenanthroline with n-butanol and disperse it by ultrasonication to obtain the 1,10-phenanthroline coordination solution; wherein, the mass ratio of 1,10-phenanthroline to n-butanol is 1:14-23; and the mass ratio of 1,10-phenanthroline to nickel-based catalyst filter cake in the 1,10-phenanthroline coordination solution is 0.4-2.7:

1.

6. The method for preparing the nickel-based hydrogenation catalyst according to claim 1, characterized in that... In step (3), the stirring reaction temperature is 40-70℃ and the stirring reaction time is 1-3h.

7. The method for preparing the nickel-based hydrogenation catalyst according to claim 1, characterized in that... The method for preparing the polydimethylsiloxane solution in step (3) is to stir and mix polydimethylsiloxane with n-butanol to obtain a polydimethylsiloxane solution; wherein the mass ratio of polydimethylsiloxane to n-butanol is 1:20-30; the mass of polydimethylsiloxane in the polydimethylsiloxane solution is 3-10% of the mass of the nickel-based catalyst filter cake.

8. The method for preparing the nickel-based hydrogenation catalyst according to claim 1, characterized in that... In step (3), the stirring temperature is 50-70℃ and the stirring time is 0.5-2h.

9. The method for preparing the nickel-based hydrogenation catalyst according to claim 1, characterized in that... The heating temperature in step (4) is 115-135℃.

10. The method for preparing the nickel-based hydrogenation catalyst according to claim 1, characterized in that... In step (4), the heat treatment temperature is 200-300℃, the heat treatment time is 2-5h, and the heat treatment atmosphere is nitrogen atmosphere; the reduction temperature is 300-400℃, the reduction time is 2-5h, and the reduction atmosphere is hydrogen atmosphere.

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