Catalyst for preparing bio-based C17 n-alkanes and preparation method thereof

Abstract

The invention provides a catalyst for preparing bio-based C17 n-alkanes and a preparation method thereof, and the preparation method comprises the following steps: step 1, mixing magnesium aluminate spinel, TiO2 and a beta molecular sieve, grinding, then mixing with pseudo-boehmite and sesbania powder, molding, and roasting to obtain a catalyst carrier; step 2, loading an active component on the catalyst carrier to obtain the catalyst, wherein the mass ratio of the magnesium aluminate spinel to the TiO2 to the beta molecular sieve is 100: (0.05-0.5): (1.0-5.0). The TiO2, the beta molecular sieve and the magnesium aluminate spinel are mixed and modified, and when the prepared catalyst is used for preparing bio-based C17 n-alkanes from animal and vegetable oil, the conversion rate is high, and the n-alkanes selectivity is high.

Description

Technical Field

[0001] This invention belongs to the field of catalytic materials, specifically relating to a catalyst for preparing bio-based C17 n-alkanes and its preparation method. Background Technology

[0002] n-Alkanes are called liquid paraffins because they are transparent, colorless, or pale yellow liquids at room temperature. Based on their fractions, they can be divided into light liquid paraffins (C9–C13) and heavy liquid paraffins (C14–C16). C15–C18 n-alkanes are mainly used in phase change materials, as well as in pharmaceutical cold chain logistics, phase change energy storage buildings, phase change microcapsules for textiles, and temperature control for electronic components. As solvents, they can also be used for separating and analyzing lower hydrocarbons, as dewaxing solvents, in machining oils, as base oils for special rust-preventive oils, as base oils for metalworking, as metal cleaning agents, and as gas chromatography references and stationary phases. They can also be used for gas storage functions such as hydrogen and nitrogen storage.

[0003] Heptadecane has wide applications in functional temperature-regulating textiles, building energy conservation, and cold chain transportation. As a phase change material, heptadecane has a phase change temperature of 22℃, a purity ranging from 99.7% to 99.9%, and an enthalpy of 218 joules / gram. Besides its use as a phase change material, heptadecane can also be fermented to produce heptadecanedioic acid, which can be used to artificially synthesize the precious fragrance civet. Civet is an indispensable raw material in high-grade fragrances and scented products in the fragrance industry, possessing a valuable and delicate animalic aroma and aroma-fixing and preserving properties. Therefore, civet has always been regarded as an indispensable treasure in cosmetic fragrance blending by world-renowned perfumers. Heptadecane is also an environmentally friendly, renewable, pure plant-extracted, natural, and pollution-free non-polar organic solvent, particularly suitable for skin-adhesive applications and ointments. It is an excellent substitute for mineral oil, possessing gloss, lubrication, skin-moisturizing properties, and a non-greasy feel. Cosmetic applications include: face creams and lotions, makeup, hair care products (shampoo, conditioner, styling gel), deodorants, sunscreens and lotions, makeup removers, shower gels, and hand soaps / soaps.

[0004] In industrial production, the main raw materials for n-alkanes are petroleum wax and Fischer-Tropsch synthetic oil wax. When producing n-alkanes from petroleum wax and Fischer-Tropsch synthetic oil wax, the production process is complex and requires stringent conditions due to the presence of complex components such as alkenes, isoalkanes, cycloalkanes, aromatics, and compounds containing oxygen, sulfur, and nitrogen. This necessitates deep hydrogenation refining, distillation, and separation of n- and isoalkanes for purification.

[0005] Besides using petroleum wax and Fischer-Tropsch synthetic oil wax as raw materials to produce monomeric n-alkanes, there is also the production of monomeric n-alkanes by hydrogenating and deoxygenating animal and vegetable oil esters. However, these methods often suffer from problems such as low conversion rates of animal and vegetable oils into monomeric alkanes, low selectivity for decarbonylation and decarboxylation, and the presence of C16 and C18 byproducts in the products.

[0006] CN201810834967 discloses a method for preparing a vegetable oil hydrodeoxygenation catalyst. The method involves uniformly mixing MgAl2O4 powder, aluminum hydroxide dry gel, and guar gum powder, extruding the mixture into strips, and calcining it to obtain a catalyst support. This support is loaded with nickel-molybdenum active components to produce second-generation biodiesel, achieving a deoxygenation conversion rate close to 100%. Pentadecane and heptadecane appear as byproducts, but their selectivity is not high.

[0007] CN202110942495 discloses a water-resistant core-shell catalyst for the hydrodeoxygenation of vegetable oil, which assembles Ni-Al-Mo7O on the surface of alumina. 24 6- LDHs shell structure yielded a Ni-Mo / γ-Al2O3 core-shell catalyst, which significantly improved water stability and provided mild reaction conditions in the hydrodeoxygenation reaction of methyl palmitate, a model compound from vegetable oil. However, in the hydrodeoxygenation reaction, n-pentadecane appeared as a byproduct when the deoxygenation conversion reached 86%, with a selectivity of only 45%. The selectivity of n-pentadecane was not high, and a large amount of n-hexadecane was generated.

[0008] CN105944750B discloses a highly selective hydrodecarboxylation catalyst for oils and fats and its preparation method. Based on the dry weight of oxides, the first support component, the second support component, and the active component account for 10-60%, 15-65%, and 5-35% of the catalyst weight, respectively. The first support component includes any one or more of Al₂O₃, TiO₂, SiO₂, MgO, and SB powder; the second support component is a modified molecular sieve, including any one or more of ZSM-5, Y zeolite, β zeolite, SAPO-11, and ZSM-22; the active component includes any two or more of the acid salts or ammonium salts of cobalt, molybdenum, nickel, and tungsten. The reaction is carried out at a temperature of 200-450℃, a pressure of 1.0-6.5 MPa, and an oil / fat volumetric space velocity of 0.5-4.0 h⁻¹. -1 Under these conditions, the selectivity for hydrogenation decarboxylation is greater than 70%.

[0009] CN202210076519 discloses a highly selective catalyst for the hydrodecarboxylation of bio-oils, its preparation method, and its application. The catalyst uses surface-modified silicon carbide as a support and a noble metal as the active component, wherein the noble metal accounts for 0.5-2% of the catalyst's mass. The preparation method involves first treating silicon carbide with a mixture of halogen compounds and inert gases to obtain surface-modified silicon carbide; finally, the surface-modified silicon carbide is used as a support to load the noble metal, resulting in a noble metal catalyst supported on modified silicon carbide. This catalyst is applied to the hydrodecarboxylation reaction of bio-oils, exhibiting high selectivity for the decarboxylation reaction, reaching a maximum decarboxylation selectivity of 86%, and reducing hydrogen consumption and water generation during the reaction process.

[0010] In the production of n-heptadecane, the fossil-based production method depends on the content of n-heptadecane in the raw material. It also requires hydrogenation to remove sulfur, nitrogen, and oxygen impurities from the oil and the presence of aromatics. The bio-based production method produces a large amount of n-octadecane due to the low selectivity of n-heptadecane. In addition, the natural forms of animal and vegetable oils are mostly C16 and C18 fatty acids or fatty acid esters, while C17 fatty acids or fatty acid esters are all in a co-occurring state and have a low content.

[0011] Current research on the preparation of n-heptadecanes via hydrodeoxygenation mainly focuses on the decarboxylation and decarbonylation of oxygen in the feedstock in the form of CO2 and CO, with the aim of reducing hydrogen consumption. The reactions are mostly batch reactions, and the deoxygenation conversion rate is not high. Therefore, further research is needed in this field on the preparation of C17 n-alkanes. Summary of the Invention

[0012] The main objective of this invention is to provide a catalyst for preparing bio-based C17 n-alkanes and its preparation method, so as to solve the problems of low conversion rate and selectivity of animal and vegetable oils to n-heptadecane in the prior art.

[0013] To achieve the above objectives, the present invention provides a method for preparing a catalyst for preparing bio-based C17 n-alkanes, comprising the following steps:

[0014] Step 1: Mix magnesium aluminum spinel, TiO2 and β molecular sieve, grind them, then mix them with a binder, shape them, and calcine them to obtain a catalyst support;

[0015] Step 2: Load the active component onto the catalyst support to obtain the catalyst;

[0016] The mass ratio of magnesium aluminum spinel, TiO2, and β molecular sieve is 100:0.05~0.5:1.0~5.0.

[0017] The method for preparing a catalyst for preparing bio-based C17 n-alkanes according to the present invention includes the following steps in the preparation method of magnesium aluminum spinel:

[0018] Magnesium salt, aluminum salt and template agent are mixed to form a solution, and a precipitant is used to carry out a precipitation reaction to obtain a precipitate. The precipitate is then dried and calcined to obtain magnesium aluminum spinel.

[0019] The method for preparing a catalyst for preparing bio-based C17 n-alkanes according to the present invention includes mixing magnesium salt, aluminum salt and acid solution to obtain solution A, mixing template agent and water to obtain solution B, then mixing solution A and solution B, adding precipitant to carry out precipitation reaction to obtain precipitate.

[0020] The method for preparing a catalyst for preparing bio-based C17 n-alkanes according to the present invention includes, in step 1, the addition of at least one of guar gum powder, a binder and a dispersant for mixing, wherein the binder is boehmite.

[0021] The method for preparing a catalyst for bio-based C17 n-alkanes according to the present invention is characterized in that the mass ratio of the mixture of magnesium aluminum spinel, TiO2, and β molecular sieve to the binder and guar gum powder is 60:30-50:1-5; the colloidal solvent is an aqueous solution of nitric acid, and the dispersant is an aqueous solution of citric acid; the calcination temperature in step 1 is 450-550℃, and the calcination time is 4-6h.

[0022] The method for preparing a catalyst for preparing bio-based C17 n-alkanes according to the present invention, wherein the active component is loaded onto the catalyst support by impregnation, and the active component is molybdenum and nickel.

[0023] The method for preparing a catalyst for preparing bio-based C17 n-alkanes according to the present invention includes a molar ratio of molybdenum to nickel of 0.15 to 0.25:1, a calcination temperature of 500 to 600°C in step 2, and a calcination time of 4 to 8 hours.

[0024] The method for preparing a catalyst for preparing bio-based C17 n-alkanes according to the present invention, wherein, based on a total mass of 100 parts of catalyst support, the active component is calculated as a metal oxide, and the mass of the active component in the catalyst is 20-30 parts.

[0025] The method for preparing a catalyst for preparing bio-based C17 n-alkanes according to the present invention, wherein the mass ratio of magnesium aluminum spinel, TiO2, and β molecular sieve is 100:0.1-0.2:1.5-2.5.

[0026] To achieve the above objectives, the present invention also provides a catalyst obtained by the above preparation method.

[0027] The beneficial effects of this invention are:

[0028] The present invention modifies TiO2, β molecular sieve and magnesium aluminum spinel by mixing them. The resulting catalyst has a high conversion rate and high selectivity for n-alkanes when used to prepare bio-based C17 n-alkanes from animal and vegetable oils. Detailed Implementation

[0029] The technical solution of the present invention will be described in detail below. The following embodiments are implemented under the premise of the technical solution of the present invention and a detailed implementation process is given. However, the protection scope of the present invention is not limited to the following embodiments. Structures or experimental methods that do not specify specific conditions in the following embodiments are generally performed under conventional conditions.

[0030] This invention provides a method for preparing a catalyst for preparing bio-based C17 n-alkanes, comprising the following steps:

[0031] Step 1: Mix magnesium aluminum spinel, TiO2 and β molecular sieve, grind them, then mix them with a binder, shape them, and calcine them to obtain a catalyst support;

[0032] Step 2: Load the active component onto the catalyst support to obtain the catalyst;

[0033] The mass ratio of magnesium aluminum spinel, TiO2, and β molecular sieve is 100:0.05~0.5:1.0~5.0.

[0034] The present invention modifies TiO2, β molecular sieve and magnesium aluminum spinel by mixing them. The resulting catalyst has a high conversion rate and high selectivity for n-alkanes when used to prepare bio-based C17 n-alkanes from animal and vegetable oils.

[0035] In detail, magnesium aluminum spinel can enhance the hydrodeoxygenation performance of catalysts and has very high water resistance, making it the main component of hydrogenation catalysts for animal and vegetable oils.

[0036] TiO2 exhibits excellent hydrothermal stability. Furthermore, TiO2 interacts strongly with metal active sites, which improves the dispersibility of active components and enhances the anti-sintering properties of supported molybdenum-nickel alloy particles. TiO2 can also enhance the catalyst's resistance to CO2 and CO toxicity and increase the amount of medium-strong acids. In synergy with magnesium aluminum spinel, it improves the selectivity of decarbonylation and decarboxylation during the reaction process, thereby increasing catalyst lifetime and activity stability.

[0037] β-zeolite possesses strong acidity and a unique pore structure, featuring a distinctive three-dimensional twelve-membered ring pore structure. This structure facilitates the effective diffusion and adsorption of molecules within the pores, allowing magnesium aluminum spinel and β-zeolite to complement each other in terms of acidity and pore structure, resulting in a synergistic effect. This enhances the catalyst's hydrogenation performance and improves the selectivity of decarbonylation and decarboxylation during the reaction process.

[0038] In one embodiment, the magnesium aluminum spinel of the present invention is prepared by hydrothermal synthesis, and the preparation method includes, for example, the following steps:

[0039] Magnesium salt, aluminum salt and template agent are mixed to form a solution, and a precipitant is used to carry out a precipitation reaction to obtain a precipitate. The precipitate is then dried and calcined to obtain magnesium aluminum spinel.

[0040] In another embodiment, magnesium salts and aluminum salts are mixed with an acid solution to obtain solution A, and a template agent is mixed with water to obtain solution B. Then, solutions A and B are mixed, and a precipitant is added to carry out a precipitation reaction to obtain a precipitate.

[0041] In this mixture, the acid solution is, for example, a citric acid solution. The magnesium salt and aluminum salt are added sequentially to the citric acid solution to obtain solution A. The magnesium salt is, for example, magnesium nitrate, the aluminum salt is, for example, aluminum nitrate, and the template agent is, for example, hexadecyltrimethylammonium bromide. In one embodiment, the molar ratio of the magnesium salt, aluminum salt, template agent, acid, and water in the mixture is 1:1-3:4-7:0.01-0.03:60-80, for example, 1:2:6:0.01:70.

[0042] In one embodiment, a solution formed by mixing magnesium salt, aluminum salt, and a template agent is heated and stirred until homogeneous. Then, a precipitant is added to induce a precipitation reaction. The precipitant, for example, is ammonia. The pH of the mixed solution is adjusted to be between 7.8 and 9.1. The mixture is then placed in a constant-temperature water bath and stirred continuously until a precipitate is obtained. The precipitate is then statically aged in an oven at room temperature for 2–4 hours, dried at 100–120°C, ground to 300–400 mesh, and calcined at 650–750°C with a heating rate of 2–3°C / min for 6–10 hours to obtain magnesium aluminum spinel powder.

[0043] The present invention does not impose any particular limitation on the source of TiO2 and β molecular sieve, and they can be commercially available products. In one embodiment, the mass ratio of magnesium aluminum spinel, TiO2, and β molecular sieve is 100:0.1-0.2:1.5-2.5.

[0044] This invention does not impose any particular limitation on the grinding method of magnesium aluminum spinel, TiO2, and β molecular sieve; any conventional method in the art is acceptable. In one embodiment, at least one of guar gum powder, a peptizing agent, and a dispersant is added during the mixing of the magnesium aluminum spinel, TiO2, and β molecular sieve with the binder in step 1. The binder is, for example, boehmite; the peptizing agent is, for example, an aqueous solution of nitric acid; and the dispersant is, for example, an aqueous solution of citric acid.

[0045] Guaranteed sesame powder primarily functions as a binder, lubricant, extrusion aid, and pore-forming agent. It enhances adhesion, making the molded product easier to shape; it lubricates during extrusion, reducing friction and improving production efficiency; and during calcination, it undergoes pyrolysis, forming pores that help increase the catalyst's specific surface area and activity.

[0046] The main function of nitric acid is to regulate adhesion and strength. Nitric acid can act as a binder, influencing the catalyst's molding effect by adjusting its adhesion and strength. It can also react with other components in the catalyst to form stable compounds, thereby enhancing the catalyst's mechanical strength and stability.

[0047] Citric acid can improve the dispersion of active components on the support surface through chelation and isolation effects. Specifically, citric acid can form complexes with metal ions, thereby preventing the aggregation of metal ions on the support surface and increasing their dispersibility. This improved dispersibility helps the catalyst exhibit higher activity and selectivity in the reaction.

[0048] In one embodiment, the mass ratio of the mixture of magnesium aluminum spinel, TiO2, and β-molecular sieve in step 1 to pseudoboehmite and guar gum powder is 60:30-50:1-5. Nitric acid aqueous solution and / or citric acid aqueous solution are added to the mixture of magnesium aluminum spinel, TiO2, β-molecular sieve, pseudoboehmite, and guar gum powder. The concentration of the nitric acid aqueous solution is, for example, 3-5 wt%, and the concentration of the citric acid aqueous solution is, for example, 2-6 wt%. The mixture is stirred into fine granules, kneaded 2-3 times using a twin-screw extruder, and then... The perforated plate is extruded into strips. The wet strips are allowed to air dry naturally at room temperature, and then calcined in a muffle furnace to obtain the catalyst support. The calcination temperature is, for example, 450-550℃, and the calcination time is, for example, 4-6 hours.

[0049] This invention does not particularly limit the manner in which the active component is supported on the catalyst support. In one embodiment, the support method is impregnation, such as equal-volume impregnation or excess impregnation. In this invention, based on a total mass of 100 parts of the catalyst support, the active component, calculated as a metal oxide, comprises 20 to 30 parts by mass of the active component in the catalyst. The active component of this invention can be molybdenum and nickel, with a molar ratio of molybdenum to nickel, for example, 0.15 to 0.25:1.

[0050] In one embodiment, an impregnation solution is formed from the active component precursor and used to impregnate the catalyst support. After impregnation, the solution is cured at room temperature for 2 hours, with stirring every 20 minutes to ensure uniform impregnation. After curing, the solution is poured into a crucible and placed in a drying oven at 110-120°C for 4-8 hours, followed by calcination at 500-600°C for 4-8 hours to obtain the catalyst. The mass ratio of the impregnation solution to the support is, for example, 0.6-0.8:1, specifically, for example, 0.7:1.

[0051] In one embodiment, the precursor of nickel can be nickel nitrate, and the precursor of molybdenum can be ammonium molybdate heptahydrate, but the present invention is not limited thereto.

[0052] The catalyst of this invention can be used for hydrogenation, decarbonylation, and decarboxylation reactions of animal and vegetable oils to prepare C17 n-alkanes. It has high water resistance, high resistance to CO2 and CO toxicity, and high to medium strong acid content. It can control the decarbonylation and decarboxylation reactions in the reaction process, improve the selectivity and yield of the target monomer C17 n-alkanes. The selectivity of the target monomer n-alkanes can be above 94%, which can reduce the pressure of subsequent separation.

[0053] Specifically, nickel is beneficial for hydrogenation decarboxylation / decarbonylation reactions, while molybdenum is beneficial for hydrogenation dehydration reactions. At a low molybdenum-nickel ratio, the total acidity of the catalyst can be increased with the increase of the molybdenum-nickel ratio. The increase in acidity is beneficial for the breaking of C-C bonds during the hydrogenation deoxygenation of vegetable oils, and the catalytic performance of the catalyst shifts towards decarbonylation / decarboxylation. Adding an appropriate amount of nickel can promote the reduction of MoO3, which is more beneficial for the reduction of the catalyst.

[0054] In this invention, animal and vegetable oils include castor oil, cottonseed oil, jatropha oil, tung oil, waste cooking oil, palm oil, and lipids, or any combination thereof. In one embodiment, the animal and vegetable oils are refined animal and vegetable oils. The animal and vegetable oils are mixed with a solvent and, in a fixed-bed reactor, under the action of the aforementioned catalyst, a hydrodeoxygenation reaction is carried out at a temperature of 340–380°C, a reaction pressure of 1.5–2.5 MPa, and a reaction mass hourly space velocity of 1.5–2.5 h⁻¹. -1 The hydrogen-to-oil volume ratio is 200–600:1, and the solvent volume accounts for 70–90% of the reaction mixture. A hydrogenation-decarbonylation and decarboxylation reaction is carried out to obtain C17 n-alkanes. The solvent can be cyclohexane, n-heptadecane, etc.

[0055] The technical solution of the present invention will be further described in detail below through specific embodiments. Unless otherwise specified, the reagents and materials mentioned can be obtained from commercial channels.

[0056] Magnesium nitrate: Magnesium nitrate hexahydrate, Tianjin Fuchen, 98%

[0057] Aluminum nitrate: Tianjin Fuchen, 99%

[0058] Nickel nitrate: Nickel nitrate hexahydrate, Aladdin reagent, AR, 98%

[0059] Ammonium molybdate heptahydrate: Shanghai Yihe Biotechnology, AR, 99.95%

[0060] Citric acid: Jinan Century Tongda, 95%

[0061] Nitric acid: Tianjin Kemio Reagent Co., Ltd., AR, 70%

[0062] Ammonia solution: Tianjin Kemio Reagent Co., Ltd., AR, 25%

[0063] Hexadecyltrimethylammonium bromide: Aladdin reagent, AR, 98%

[0064] Boehmite: Yangzhou Zhongtianli New Material Co., Ltd., industrial agent, 99.9%.

[0065] β-molecular sieve: Tianjin Nanhua Catalyst Co., Ltd.

[0066] TiO2 powder: Hubei Dechao Chemical Co., Ltd.

[0067] Cottonseed oil: Yunnan Shenyu

[0068] Tung oil refined from ancient trees: Yunnan Shenyu

[0069] Silicon carbide: Shandong Jinmeng New Material Co., Ltd.

[0070] Preparation of magnesium aluminum spinel powder:

[0071] A hydrothermal synthesis method was used. A certain amount of citric acid was weighed and added to deionized water and stirred until completely dissolved. Then, magnesium nitrate and aluminum nitrate were weighed and added sequentially to the citric acid aqueous solution to obtain solution A. A certain amount of hexadecyltrimethylammonium bromide was weighed and dissolved in deionized water to obtain solution B. The molar ratio of magnesium nitrate, aluminum nitrate, hexadecyltrimethylammonium bromide, citric acid, and water was 1:2:6:0.01:70.

[0072] Solution A and solution B are mixed, heated and stirred until homogeneous. The pH of the mixed solution is adjusted by adding ammonia dropwise to a range of 7.8–9.1. The mixed solution is placed in a constant temperature water bath and stirred until a precipitate is obtained. The precipitate is statically aged in an oven at room temperature for 2–4 hours. After drying at 100–120°C, it is ground to 300–400 mesh and calcined at 680–720°C with a heating rate of 2–3°C / min for 6–10 hours to obtain magnesium aluminum spinel powder.

[0073] Example 1

[0074] (1) Preparation of the molded carrier

[0075] TiO2 powder, β-molecular sieve, and magnesium aluminum spinel powder were ground evenly. The magnesium aluminum spinel was 100 parts by weight, TiO2 powder was 0.1 parts, and β-molecular sieve powder was 1.5 parts. The mixed powders, along with boehmite and guar gum powder, were mixed in a mass ratio of 60:40:3. An aqueous solution containing 3 wt% nitric acid and 4 wt% citric acid was added, and the mixture was stirred into fine granules. The granules were then kneaded three times using a twin-screw extruder, and extruded into strips using a φ2.0 perforated plate. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500℃ for 4 hours to obtain the catalyst support.

[0076] (2) Active ingredient loading

[0077] A certain amount of nickel nitrate was dissolved in deionized water, and then ammonium molybdate heptahydrate was added. The mixture was heated and stirred until completely dissolved to prepare an impregnation solution. The solution consisted of 100 parts by weight of the carrier and 20 parts by weight of the active component (MoO3 + NiO). The molar ratio of molybdenum to nickel was 0.15:1, and the mass ratio of the impregnation solution to the carrier was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 6 hours. Finally, it was calcined at 650°C for 6 hours to obtain the desired hydrodeoxygenation catalyst.

[0078] (3) Catalyst Evaluation

[0079] This invention involves mixing refined tung oil with a solvent and reacting the mixture in a fixed-bed reactor under the action of the aforementioned catalyst. The reaction temperature is 340°C, the reaction pressure is 1.5 MPa, and the reaction mass hourly space velocity is 2.5 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 200:1 and a solvent content of 90%, a mixture of alkanes was obtained.

[0080] Example 2

[0081] (1) Preparation of the molded carrier

[0082] TiO2 powder, β-molecular sieve, and magnesium aluminum spinel powder were ground evenly. The magnesium aluminum spinel was 100 parts by weight, TiO2 powder was 0.1 parts, and β-molecular sieve powder was 2 parts. The mixed powders, along with boehmite and guar gum powder, were mixed in a mass ratio of 60:40:3. An aqueous solution containing 3 wt% nitric acid and 4 wt% citric acid was added, and the mixture was stirred into fine granules. The granules were then kneaded three times using a twin-screw extruder, and extruded into strips using a φ2.0 perforated plate. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500℃ for 4 hours to obtain the catalyst support.

[0083] (2) Active ingredient loading

[0084] A certain amount of nickel nitrate was weighed and dissolved in deionized water. Ammonium molybdate heptahydrate was then added, and the mixture was heated and stirred until completely dissolved to prepare an impregnation solution. The solution consisted of 100 parts by weight of the carrier and 25 parts by weight of the active component (MoO3 + NiO). The molar ratio of molybdenum to nickel was 0.2:1, and the mass ratio of the impregnation solution to the carrier was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 8 hours. Finally, it was calcined at 550°C for 6 hours to obtain the desired hydrodeoxygenation catalyst.

[0085] (3) Catalyst Evaluation

[0086] This invention involves mixing refined tung oil with a solvent and reacting the mixture in a fixed-bed reactor under the action of the aforementioned catalyst. The reaction temperature is 350°C, the reaction pressure is 2 MPa, and the reaction mass hourly space velocity is 2 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 400:1 and a solvent content of 90%, a mixture of alkanes was obtained.

[0087] Example 3

[0088] (1) Preparation of the molded carrier

[0089] TiO2 powder, β-molecular sieve, and magnesium aluminum spinel powder were ground evenly. The magnesium aluminum spinel was 100 parts by weight, TiO2 powder was 0.1 parts, and β-molecular sieve powder was 2.5 parts. The mixed powders, along with boehmite and guar gum powder, were mixed in a mass ratio of 60:40:3. An aqueous solution containing 3 wt% nitric acid and 4 wt% citric acid was added, and the mixture was stirred into fine granules. The granules were then kneaded three times using a twin-screw extruder, and extruded into strips using a φ2.0 perforated plate. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500℃ for 4 hours to obtain the catalyst support.

[0090] (2) Active ingredient loading

[0091] A certain amount of nickel nitrate was weighed and dissolved in deionized water. Ammonium molybdate heptahydrate was then added, and the mixture was heated and stirred until completely dissolved to prepare an impregnation solution. The solution consisted of 100 parts by weight of the carrier and 30 parts by weight of the active component (MoO3 + NiO). The molar ratio of molybdenum to nickel was 0.25:1, and the mass ratio of the impregnation solution to the carrier was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 6 hours. Finally, it was calcined at 600°C for 5 hours to obtain the desired hydrodeoxygenation catalyst.

[0092] (3) Catalyst Evaluation

[0093] This invention involves mixing refined tung oil with a solvent and reacting the mixture in a fixed-bed reactor under the action of the aforementioned catalyst. The reaction temperature is 370°C, the reaction pressure is 2.5 MPa, and the reaction mass hourly space velocity (WHSV) is 1.5 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 600:1 and a solvent content of 80%, a mixture of alkanes was obtained.

[0094] Example 4

[0095] (1) Preparation of the molded carrier

[0096] TiO2 powder, β-molecular sieve, and magnesium aluminum spinel powder were ground evenly. The magnesium aluminum spinel was 100 parts by weight, TiO2 powder was 0.15 parts, and β-molecular sieve powder was 1.5 parts. The mixed powders, along with boehmite and guar gum powder, were mixed in a mass ratio of 60:40:3. An aqueous solution containing 3 wt% nitric acid and 4 wt% citric acid was added, and the mixture was stirred into fine granules. The granules were then kneaded three times using a twin-screw extruder, and extruded into strips using a φ2.0 perforated plate. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500℃ for 4 hours to obtain the catalyst support.

[0097] (2) Active ingredient loading

[0098] A certain amount of nickel nitrate was weighed and dissolved in deionized water. Ammonium molybdate heptahydrate was then added, and the mixture was heated and stirred until completely dissolved to prepare an impregnation solution. The solution consisted of 100 parts by weight of the carrier and 20 parts by weight of the active component (MoO3 + NiO). The molar ratio of molybdenum to nickel was 0.15:1, and the mass ratio of the impregnation solution to the carrier was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 6 hours. Finally, it was calcined at 650°C for 6 hours to obtain the desired hydrodeoxygenation catalyst.

[0099] (3) Catalyst Evaluation

[0100] This invention involves mixing refined tung oil with a solvent and reacting the mixture in a fixed-bed reactor under the action of the aforementioned catalyst. The reaction temperature is 340°C, the reaction pressure is 1.5 MPa, and the reaction mass hourly space velocity (WHSV) is 2 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 250:1 and a solvent content of 85%, a mixture of alkanes was obtained.

[0101] Example 5

[0102] (1) Preparation of the molded carrier

[0103] TiO2 powder, β-molecular sieve, and magnesium aluminum spinel powder were ground evenly. The magnesium aluminum spinel was 100 parts by weight, TiO2 powder was 0.15 parts, and β-molecular sieve powder was 2 parts. The mixed powders, along with boehmite and guar gum powder, were mixed in a mass ratio of 60:40:3. An aqueous solution containing 3 wt% nitric acid and 4 wt% citric acid was added, and the mixture was stirred into fine granules. The granules were then kneaded three times using a twin-screw extruder, and extruded into strips using a φ2.0 perforated plate. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500℃ for 4 hours to obtain the catalyst support.

[0104] (2) Active ingredient loading

[0105] A certain amount of nickel nitrate was weighed and dissolved in deionized water. Ammonium molybdate heptahydrate was then added, and the mixture was heated and stirred until completely dissolved to prepare an impregnation solution. The solution consisted of 100 parts by weight of the carrier and 25 parts by weight of the active component (MoO3 + NiO). The molar ratio of molybdenum to nickel was 0.2:1, and the mass ratio of the impregnation solution to the carrier was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 8 hours. Finally, it was calcined at 550°C for 6 hours to obtain the desired hydrodeoxygenation catalyst.

[0106] (3) Catalyst Evaluation

[0107] This invention involves mixing refined tung oil with a solvent and reacting the mixture in a fixed-bed reactor under the action of the aforementioned catalyst. The reaction temperature is 360°C, the reaction pressure is 2 MPa, and the reaction mass hourly space velocity is 2 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 350:1 and a solvent content of 80%, a mixture of alkanes was obtained.

[0108] Example 6

[0109] (1) Preparation of the molded carrier

[0110] TiO2 powder, β-molecular sieve, and magnesium aluminum spinel powder were ground evenly. The magnesium aluminum spinel was 100 parts by weight, TiO2 powder was 0.15 parts, and β-molecular sieve powder was 2.5 parts. The mixed powders, along with boehmite and guar gum powder, were mixed in a mass ratio of 60:40:3. An aqueous solution containing 3 wt% nitric acid and 4 wt% citric acid was added, and the mixture was stirred into fine granules. The granules were then kneaded three times using a twin-screw extruder, and extruded into strips using a φ2.0 perforated plate. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500℃ for 4 hours to obtain the catalyst support.

[0111] (2) Active ingredient loading

[0112] A certain amount of nickel nitrate was weighed and dissolved in deionized water. Ammonium molybdate heptahydrate was then added, and the mixture was heated and stirred until completely dissolved to prepare an impregnation solution. The solution consisted of 100 parts by weight of the carrier and 30 parts by weight of the active component (MoO3 + NiO). The molar ratio of molybdenum to nickel was 0.25:1, and the mass ratio of the impregnation solution to the carrier was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 6 hours. Finally, it was calcined at 600°C for 6 hours to obtain the desired hydrodeoxygenation catalyst.

[0113] (3) Catalyst Evaluation

[0114] This invention involves mixing refined tung oil with a solvent and reacting the mixture in a fixed-bed reactor under the action of the aforementioned catalyst. The reaction temperature is 380°C, the reaction pressure is 2 MPa, and the reaction mass hourly space velocity is 1.5 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 550:1 and a solvent content of 75%, a mixture of alkanes was obtained.

[0115] Example 7

[0116] (1) Preparation of the molded carrier

[0117] TiO2 powder, β-molecular sieve, and magnesium aluminum spinel powder were ground evenly. The magnesium aluminum spinel was 100 parts by weight, TiO2 powder was 0.2 parts, and β-molecular sieve powder was 1.5 parts. The mixed powders, along with boehmite and guar gum powder, were mixed in a mass ratio of 60:40:3. An aqueous solution containing 3 wt% nitric acid and 4 wt% citric acid was added, and the mixture was stirred into fine granules. The granules were then kneaded three times using a twin-screw extruder, and extruded into strips using a φ2.0 perforated plate. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500℃ for 4 hours to obtain the catalyst support.

[0118] (2) Active ingredient loading

[0119] A certain amount of nickel nitrate was weighed and dissolved in deionized water. Ammonium molybdate heptahydrate was then added, and the mixture was heated and stirred until completely dissolved to prepare an impregnation solution. The solution consisted of 100 parts by weight of the carrier and 20 parts by weight of the active component (MoO3 + NiO). The molar ratio of molybdenum to nickel was 0.15:1, and the mass ratio of the impregnation solution to the carrier was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 6 hours. Finally, it was calcined at 650°C for 6 hours to obtain the desired hydrodeoxygenation catalyst.

[0120] (3) Catalyst Evaluation

[0121] This invention involves mixing refined tung oil with a solvent and reacting the mixture in a fixed-bed reactor under the action of a catalyst. The reaction temperature is 340°C, the reaction pressure is 1.5 MPa, and the mass hourly space velocity (HHSV) is 2.5 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 350:1 and a solvent content of 85%, a mixture of alkanes was obtained.

[0122] Example 8

[0123] (1) Preparation of the molded carrier

[0124] TiO2 powder, β-molecular sieve, and magnesium aluminum spinel powder were ground evenly. The magnesium aluminum spinel was 100 parts by weight, TiO2 powder was 0.2 parts, and β-molecular sieve powder was 2 parts. The mixed powders, along with boehmite and guar gum powder, were mixed in a mass ratio of 60:40:3. An aqueous solution containing 3 wt% nitric acid and 4 wt% citric acid was added, and the mixture was stirred into fine granules. The granules were then kneaded three times using a twin-screw extruder, and extruded into strips using a φ2.0 perforated plate. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500℃ for 4 hours to obtain the catalyst support.

[0125] (2) Active ingredient loading

[0126] A certain amount of nickel nitrate was weighed and dissolved in deionized water. Ammonium molybdate heptahydrate was then added, and the mixture was heated and stirred until completely dissolved to prepare an impregnation solution. The solution consisted of 100 parts by weight of the carrier and 25 parts by weight of the active component (MoO3 + NiO). The molar ratio of molybdenum to nickel was 0.2:1, and the mass ratio of the impregnation solution to the carrier was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 8 hours. Finally, it was calcined at 550°C for 6 hours to obtain the desired hydrodeoxygenation catalyst.

[0127] (3) Catalyst Evaluation

[0128] This invention involves mixing refined tung oil with a solvent and reacting the mixture in a fixed-bed reactor under the action of a catalyst. The reaction temperature is 360°C, the reaction pressure is 2 MPa, and the reaction mass hourly space velocity is 2 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 400:1 and a solvent content of 80%, a mixture of alkanes was obtained.

[0129] Example 9

[0130] (1) Preparation of the molded carrier

[0131] TiO2 powder, β-molecular sieve, and magnesium aluminum spinel powder were ground evenly. The magnesium aluminum spinel was 100 parts by weight, TiO2 powder was 0.2 parts, and β-molecular sieve powder was 2.5 parts. The mixed powders, along with boehmite and guar gum powder, were mixed in a mass ratio of 60:40:3. An aqueous solution containing 3 wt% nitric acid and 4 wt% citric acid was added, and the mixture was stirred into fine granules. The granules were then kneaded three times using a twin-screw extruder, and extruded into strips using a φ2.0 perforated plate. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500℃ for 4 hours to obtain the catalyst support.

[0132] (2) Active ingredient loading

[0133] A certain amount of nickel nitrate was weighed and dissolved in deionized water. Ammonium molybdate heptahydrate was then added, and the mixture was heated and stirred until completely dissolved to prepare an impregnation solution. The solution consisted of 100 parts by weight of the carrier and 30 parts by weight of the active component (MoO3 + NiO). The molar ratio of molybdenum to nickel was 0.25:1, and the mass ratio of the impregnation solution to the carrier was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 6 hours. Finally, it was calcined at 600°C for 5 hours to obtain the desired hydrodeoxygenation catalyst.

[0134] (3) Catalyst Evaluation

[0135] This invention involves mixing refined tung oil with a solvent and reacting the mixture in a fixed-bed reactor under the action of the aforementioned catalyst. The reaction temperature is 370°C, the reaction pressure is 1.5 MPa, and the reaction mass hourly space velocity (WHSV) is 1.5 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 600:1 and a solvent content of 70%, a mixture of alkanes was obtained.

[0136] Example 10

[0137] (1) Preparation of the molded carrier

[0138] TiO2 powder, β-molecular sieve, and magnesium aluminum spinel powder were ground evenly. The magnesium aluminum spinel was 100 parts by weight, TiO2 powder was 0.15 parts, and β-molecular sieve powder was 2 parts. The mixed powders, along with boehmite and guar gum powder, were mixed in a mass ratio of 60:40:3. An aqueous solution containing 3 wt% nitric acid and 4 wt% citric acid was added, and the mixture was stirred into fine granules. The granules were then kneaded three times using a twin-screw extruder, and extruded into strips using a φ2.0 perforated plate. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500℃ for 4 hours to obtain the catalyst support.

[0139] (2) Active ingredient loading

[0140] A certain amount of nickel nitrate was weighed and dissolved in deionized water. Ammonium molybdate heptahydrate was then added, and the mixture was heated and stirred until completely dissolved to prepare an impregnation solution. The solution consisted of 100 parts by weight of the carrier and 25 parts by weight of the active component (MoO3 + NiO). The molar ratio of molybdenum to nickel was 0.2:1, and the mass ratio of the impregnation solution to the carrier was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 8 hours. Finally, it was calcined at 550°C for 6 hours to obtain the desired hydrodeoxygenation catalyst.

[0141] (3) Catalyst Evaluation

[0142] This invention involves mixing refined cottonseed oil with a solvent and reacting the mixture in a fixed-bed reactor under the action of the aforementioned catalyst. The reaction temperature is 360°C, the reaction pressure is 2 MPa, and the reaction mass hourly space velocity is 2 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 350:1 and a solvent content of 80%, a mixture of alkanes was obtained.

[0143] Comparative Example 1

[0144] (1) Catalyst preparation

[0145] 20g of silicon carbide was placed in a tube furnace and treated at 500℃ with a mixture of hydrogen fluoride and argon for 10 minutes, wherein the volume fraction of hydrogen fluoride in the mixture was 0.1%. Then, it was calcined at 300℃ for 24 hours. The calcined surface-modified silicon carbide was then treated in a 50% nitric acid solution for 2 hours, rinsed with distilled water until neutral, and dried at 100℃ for 24 hours. Chloroplatinic acid was dissolved in a solution of water and ethanol, with an active component Pt loading of 0.5%. The dried surface-modified silicon carbide support was then impregnated in a chloroplatinic acid solution at 20℃ for 12 hours, dried at 120℃ for 12 hours, and finally calcined at 200℃ for 24 hours to obtain a highly selective oil hydrodecarboxylation catalyst.

[0146] (2) Catalyst Evaluation

[0147] The catalyst reduced with hydrogen was added to a high-temperature and high-pressure reactor, and then cottonseed oil was added. The mass ratio of cottonseed oil to catalyst was 20:1. The reactor was pressurized with hydrogen to 5.0 MPa and heated to 350°C for decarboxylation reaction for 1 hour. The decarboxylation product was separated after cooling.

[0148] Comparative Example 2

[0149] (1) Preparation of the molded carrier

[0150] Magnesium aluminum spinel powder, boehmite, and guar gum powder were mixed in a mass ratio of 60:40:3. An aqueous solution containing 3 wt% nitric acid and 4 wt% citric acid was added, and the mixture was stirred into fine granules. The granules were then kneaded three times using a twin-screw extruder and extruded into strips using a φ2.0 perforated plate. The wet strips were allowed to air dry naturally at room temperature and then calcined in a muffle furnace at 500℃ for 4 hours to obtain the catalyst support.

[0151] (2) Active ingredient loading

[0152] A certain amount of nickel nitrate was weighed and dissolved in deionized water. Ammonium molybdate heptahydrate was then added, and the mixture was heated and stirred until completely dissolved to prepare an impregnation solution. The solution consisted of 100 parts by weight of the carrier and 20 parts by weight of the active component (MoO3 + NiO). The molar ratio of molybdenum to nickel was 0.15, and the mass ratio of the impregnation solution to the carrier was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 5 hours. Finally, it was calcined at 500°C for 6 hours to obtain the desired hydrodeoxygenation catalyst.

[0153] (3) Catalyst Evaluation

[0154] Refined tung oil was mixed with a solvent and reacted in a fixed-bed reactor under the action of the aforementioned catalyst at a reaction temperature of 340℃, a reaction pressure of 1.5 MPa, and a reaction mass hourly space velocity of 1.5 h⁻¹. ～1 With a hydrogen-to-oil volume ratio of 200:1 and a solvent content of 70%, a mixture of alkanes was obtained.

[0155] Comparative Example 3

[0156] (1) Preparation of the molding carrier:

[0157] TiO2 powder and magnesium aluminum spinel powder were mixed and ground evenly. Taking 100 parts magnesium aluminum spinel as the mass and 0.1 parts TiO2 powder as the mass, the mixed powder, boehmite, and guar gum powder were mixed at a mass ratio of 60:40:3. An aqueous solution containing 4 wt% nitric acid and 6 wt% citric acid was added, and the mixture was stirred into fine granules. The granules were then kneaded three times using a twin-screw extruder, and then extruded into strips using a φ2.0 perforated plate. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 600℃ for 5 hours to obtain the catalyst support.

[0158] (3) Active ingredient loading

[0159] A certain amount of nickel nitrate was weighed and dissolved in deionized water. Ammonium molybdate heptahydrate was then added, and the mixture was heated and stirred until completely dissolved to prepare an impregnation solution. The solution consisted of 100 parts by weight of the carrier and 30 parts by weight of the active component (MoO3 + NiO). The molar ratio of molybdenum to nickel was 0.25:1, and the mass ratio of the impregnation solution to the carrier was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 6 hours. Finally, it was calcined at 650°C for 6 hours to obtain the desired hydrodeoxygenation catalyst.

[0160] (4) Catalyst Evaluation

[0161] Refined tung oil was mixed with a solvent and reacted in a fixed-bed reactor under the action of the aforementioned catalyst at a reaction temperature of 380℃, a reaction pressure of 2.5 MPa, and a reaction mass hourly space velocity of 2.5 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 600:1 and a solvent content of 90%, a mixture of alkanes was obtained.

[0162] Comparative Example 4

[0163] (1) Preparation of the molded carrier

[0164] β-molecular sieve and magnesium aluminum spinel powder were mixed and ground evenly. Taking 100 parts magnesium aluminum spinel and 1.5 parts β-molecular sieve powder as the weight, the mixed powder, pseudoboehmite, and guar gum powder were mixed at a mass ratio of 60:40:3. An aqueous solution containing 5% nitric acid and 2% citric acid was added, and the mixture was stirred into fine granules. The granules were then kneaded three times using a twin-screw extruder, and extruded into strips using a φ2.0 perforated plate. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500℃ for 6 hours to obtain the catalyst support.

[0165] (3) Active ingredient loading

[0166] A certain amount of nickel nitrate was dissolved in deionized water, and then ammonium molybdate heptahydrate was added. The mixture was heated and stirred until completely dissolved to prepare an impregnation solution. The solution consisted of 100 parts by weight of the carrier and 25 parts by weight of the active component (MoO3 + NiO). The molar ratio of molybdenum to nickel was 0.25:1, and the mass ratio of the impregnation solution to the carrier was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 8 hours. Finally, it was calcined at 600°C for 8 hours to obtain the desired hydrodeoxygenation catalyst.

[0167] (4) Catalyst Evaluation

[0168] Refined tung oil was mixed with a solvent and reacted in a fixed-bed reactor under the action of the aforementioned catalyst at a reaction temperature of 360℃, a reaction pressure of 2.0 MPa, and a reaction mass hourly space velocity of 2 h⁻¹. -1 With a hydrogen-to-oil volume ratio of 500:1 and a solvent content of 85%, a mixture of alkanes was obtained.

[0169] Comparative Example 5

[0170] (1) Preparation of the molded carrier

[0171] Grind TiO2 powder evenly. Mix TiO2 powder, boehmite, and guar gum powder in a mass ratio of 60:40:3. Add an aqueous solution containing 3wt% nitric acid and 4wt% citric acid, and stir until fine granules are formed. Knead the mixture three times using a twin-screw extruder, and then... The perforated plate was extruded into strips. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500°C for 4 hours to obtain catalyst support A.

[0172] The β-molecular sieve is ground uniformly. β-molecular sieve powder, pseudoboehmite, and guar gum powder are added to an aqueous solution containing 3 wt% nitric acid and 4 wt% citric acid at a mass ratio of 60:40:3. The mixture is stirred into fine granules, kneaded three times using a twin-screw extruder, and then... The perforated plate was extruded into strips. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500°C for 4 hours to obtain catalyst support B.

[0173] Magnesium aluminum spinel powder is ground evenly. Magnesium aluminum spinel powder, boehmite, and guar gum powder are added to an aqueous solution containing 3 wt% nitric acid and 4 wt% citric acid at a mass ratio of 60:40:3. The mixture is stirred into fine granules, kneaded three times using a twin-screw extruder, and then... The perforated plate was extruded into strips. The wet strips were allowed to air dry naturally at room temperature, and then calcined in a muffle furnace at 500°C for 4 hours to obtain catalyst support C.

[0174] (2) Active ingredient loading

[0175] A certain amount of nickel nitrate was weighed and dissolved in deionized water. Ammonium molybdate heptahydrate was then added, and the mixture was heated and stirred until completely dissolved to obtain an impregnation solution. Using supports A, B, and C as catalyst supports, with each support weighing 100 parts and the active component weighing 20 parts (MoO3 + NiO), the molar ratio of molybdenum to nickel was 0.15:1. The mass ratio of the impregnation solution to the support was 0.7:1. After impregnation, the solution was cured at room temperature for 2 hours, stirring every 20 minutes to ensure uniform impregnation. After curing, the solution was poured into a crucible and dried in a drying oven at 120°C for 6 hours. Finally, the solution was calcined at 650°C for 6 hours to obtain the corresponding titanium-based catalyst, β-based catalyst, and magnesium-aluminum spinel catalyst.

[0176] (3) Catalyst Evaluation

[0177] The prepared titanium-based catalyst, β-based catalyst, and magnesium-aluminum spinel catalyst were mixed at a mass ratio of 0.2:1.5:100. After homogeneous mixing, the mixture was loaded into a fixed-bed reactor. Refined tung oil was mixed with a solvent, and the reaction was carried out under the action of the mixed catalyst at a reaction temperature of 340℃, a reaction pressure of 1.5MPa, and a reaction mass hourly space velocity of 2.5h⁻¹. -1 With a hydrogen-to-oil volume ratio of 350:1 and a solvent content of 85%, a mixture of alkanes was obtained.

[0178] The composition of the feedstock is shown in Table 1, and the evaluation results of the catalyst hydrodeoxygenation are shown in Table 2. Gas chromatography was used to analyze the mixed alkanes in the product, employing an Agilent HP-1 capillary column (60m × 0.25mm × 1.00μm).

[0179] Table 1 Composition of Feed Oil

[0180]

[0181]

[0182] Note: Lauric acid (C12:0) is lauric acid without carbon-carbon double bonds, linolenic acid (C18:3) is linolenic acid with three carbon-carbon double bonds, and the rest are similar.

[0183] Table 2 Evaluation results of catalysts for hydrodeoxygenation

[0184]

[0185] Note: Oxygen content was analyzed using an Elementar vario MICROCUBE (Germany). a, b, c, and d represent oxygen content calculated after dilution with cyclohexane. a: 50-fold dilution. b: 30-fold dilution. c: 10-fold dilution. d: 10-fold dilution. e: 100-fold dilution.

[0186] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a catalyst for preparing bio-based C17 n-alkanes, characterized in that, Includes the following steps: Step 1: Mix magnesium aluminum spinel, TiO2, and β molecular sieve, grind them, then mix them with a binder, shape them, and calcine them to obtain a catalyst support; Step 2: Load the active component onto the catalyst support to obtain the catalyst; The mass ratio of magnesium aluminum spinel, TiO2, and β molecular sieve is 100:0.05~0.5:1.0~5.

0.

2. The method for preparing the catalyst for preparing bio-based C17 n-alkanes according to claim 1, characterized in that, The preparation method of magnesium aluminum spinel includes the following steps: Magnesium salt, aluminum salt and template agent are mixed to form a solution, and a precipitant is used to carry out a precipitation reaction to obtain a precipitate. The precipitate is then dried and calcined to obtain magnesium aluminum spinel.

3. The method for preparing the catalyst for preparing bio-based C17 n-alkanes according to claim 2, characterized in that, Magnesium salts and aluminum salts are mixed with an acid solution to obtain solution A. A template agent is mixed with water to obtain solution B. Then, solutions A and B are mixed, and a precipitating agent is added to carry out a precipitation reaction to obtain a precipitate.

4. The method for preparing the catalyst for preparing bio-based C17 n-alkanes according to claim 1, characterized in that, Step 1 also involves mixing at least one of guar gum powder, adhesive solvent, and dispersant, wherein the binder is boehmite.

5. The method for preparing the catalyst for preparing bio-based C17 n-alkanes according to claim 4, characterized in that, The mass ratio of the mixture of magnesium aluminum spinel, TiO2, and β molecular sieve to the binder and guar gum powder is 60:30-50:1-5; the adhesive solvent is an aqueous solution of nitric acid, and the dispersant is an aqueous solution of citric acid; the calcination temperature in step 1 is 450-550℃, and the calcination time is 4-6 hours.

6. The method for preparing the catalyst for preparing bio-based C17 n-alkanes according to claim 1, characterized in that, The active components are loaded onto the catalyst support by impregnation, and the active components are molybdenum and nickel.

7. The method for preparing the catalyst for preparing bio-based C17 n-alkanes according to claim 6, characterized in that, The molar ratio of molybdenum to nickel is 0.15 to 0.25:1, and the roasting temperature in step 2 is 500 to 600°C, with a roasting time of 4 to 8 hours.

8. The method for preparing the catalyst for preparing bio-based C17 n-alkanes according to claim 1, characterized in that, With a total mass of 100 parts for the catalyst support, and the active component being a metal oxide, the mass of the active component in the catalyst is 20 to 30 parts.

9. The method for preparing the catalyst for preparing bio-based C17 n-alkanes according to claim 1, characterized in that, The mass ratio of magnesium aluminum spinel, TiO2, and β molecular sieve is 100:0.1~0.2:1.5~2.

5.

10. The catalyst obtained by the preparation method according to any one of claims 1-9.

Images