Hydrogenation dehydration catalyst and preparation method thereof

Abstract

The present invention provides a hydrogenation dehydration catalyst and a preparation method thereof, the hydrogenation dehydration catalyst is used for preparing C16 and C18 n-alkanes from animal and plant oil, the hydrogenation dehydration catalyst comprises a carrier and active components, the carrier comprises magnesium aluminate spinel, the active components comprise molybdenum and nickel, and the molar ratio of molybdenum to nickel is 85-100: 1. According to the present invention, the magnesium aluminate spinel is adopted as the carrier, the molybdenum and the nickel are adopted as the active components, and the molar ratio of the molybdenum to the nickel is controlled in the range of 85-100: 1, such that the conversion rate is high and the C18 n-alkane selectivity is high when the catalyst is used for preparing the n-alkane from the animal and plant oil.

Description

Technical Field

[0001] The invention belongs to the field of catalytic materials and relates to a hydrogenation dehydration catalyst using animal and plant oils as raw materials and a preparation method thereof. Background Art

[0002] Magnesium aluminum spinel is a new type of catalytic hydrodeoxidation material, especially it not only has the characteristics of two metal oxides, but also has new characteristics beyond two metal compounds. Magnesium aluminum spinel material has a large specific surface area and a large pore volume, and is suitable as a catalyst carrier. The catalytic performance of magnesium aluminum spinel mainly depends on the specific surface area and pore volume of the material. At the same time, magnesium aluminum spinel has high thermal stability, high mechanical strength and hardness, and has good resistance to erosion, corrosion, and spalling, and good thermal shock stability. Therefore, magnesium aluminum spinel is widely used as a catalyst and catalyst carrier in chemical reactions.

[0003] C15-C18 normal alkanes are mainly used in phase change materials, pharmaceutical cold chain logistics, phase change energy storage buildings, textile phase change microcapsules and electronic components temperature control. C18 normal alkanes can also be used as solvents to separate and analyze low-level hydrocarbons, dewaxing solvents, machining oils, base oils for special rust-proof oils, metalworking base oils, metal cleaning agents, gas chromatography references and stationary liquids. It can also be used for gas storage functions such as hydrogen storage and nitrogen storage. Among them, n-hexadecane is also used as a standard substance for determining diesel combustion quality.

[0004] The current technology for preparing monomer normal alkanes by hydrodeoxygenation is mostly used to produce mixed alkanes for the second-generation biodiesel components. There are problems such as low conversion rate of animal and vegetable oils into alkanes, low selectivity, side reactions such as decarbonylation and decarboxylation, and the presence of by-products such as C15 and C17 in the product.

[0005] CN201210322774 discloses a method for preparing alkanes by hydrodeoxygenation of non-edible animal and vegetable oils, using a molybdenum-nickel catalyst to produce mixed alkanes whose main components are C15-C18, with an alkane yield of about 82% and a C15-C18 mixed alkane yield of about 80%. Decarbonylation and decarboxylation reactions occur in the prepared mixed aromatics to generate C15 and C17 alkanes, and the selectivity is not high.

[0006] CN201711055764 discloses a method for preparing a mesoporous bulk Mo-Ni hydrodeoxygenation catalyst, wherein a soluble nickel salt, a soluble molybdenum salt and an organic acid are respectively dissolved in an ethanol aqueous solution, the solution is mixed evenly and the pH value of the mixed solution is adjusted to 1-5; a hard template is added to the mixed solution, stirred to obtain a suspension, and then the suspension is stirred until the solution forms a sol, and then subjected to ultrasonic oscillation, aged at room temperature, and dried to obtain a mixture of a dry gel and a hard template; the obtained mixture is calcined in a nitrogen atmosphere to obtain a Mo-Ni composite oxide powder; the obtained Mo-Ni composite oxide powder, an adhesive, a hard template and a field sesbania powder are mixed evenly, and then dilute nitric acid is added to extrude and form strips, and then calcined to obtain a catalyst. Using a n-octane solution containing 20% ​​tung oil as a raw material, a continuous flow fixed bed, and a deoxygenation rate of tung oil of 100%.

[0007] CN202110942495 discloses a water-resistant core-shell catalyst for hydrodeoxygenation of vegetable oil, wherein Ni-Al-Mo is assembled on the surface of alumina. 7 O 24 6- LDHs shell structure, Ni-Mo / γ-Al 2 O 3 The core-shell catalyst has greatly improved water resistance and stability in the hydrodeoxygenation reaction of the plant oil model compound methyl palmitate, and the reaction conditions are mild. However, in the hydrodeoxygenation reaction, when the deoxygenation conversion rate reaches 86%, the selectivity of n-hexadecane is only 55%, and a large amount of n-pentadecane is generated; when the n-hexadecane selectivity reaches 92%, the deoxygenation conversion rate is only 15%.

[0008] CN201910743836 discloses the synthesis and catalyst preparation of a silicon-aluminum-phosphorus material with a porous structure and its application in the hydrogenation of palm oil and other oils to produce biofuels. In the synthesis of the porous silicon-aluminum-phosphorus carrier, no amine template is added. By adjusting the silicon source and the alkali source and finding suitable hydrothermal synthesis conditions, a porous silicon-aluminum-phosphorus carrier prepared by a template-free method can be obtained. The obtained carrier does not need to be roasted. By removing the sodium ions in the crystals through ion exchange, it can be used as a catalyst for the hydrodeoxygenation, hydroisomerization and hydrocracking of palm oil and other vegetable oils to prepare biofuels. Using methylated palm oil as the raw material, when the conversion rate is as high as 99%, the C17-C18 selectivity is as high as 66.7%, and a large amount of C5-C16 alkanes are produced as by-products.

[0009] Therefore, further research on hydrogenation dehydration catalysts for animal and vegetable oils and fats is still needed in this field. Summary of the invention

[0010] The main purpose of the present invention is to provide a hydrogenation dehydration catalyst and a preparation method thereof, so as to overcome the problems in the prior art that the catalyst has low conversion rate and low selectivity when used for preparing normal alkanes from animal and vegetable oils and fats, and is prone to side reactions such as decarbonylation and decarboxylation.

[0011] In order to achieve the above-mentioned object, the present invention provides a hydrogenation dehydration catalyst for preparing C16 and C18 normal alkanes from animal and vegetable oils and fats. The hydrogenation dehydration catalyst comprises a carrier and an active component. The carrier comprises magnesium aluminum spinel, and the active component comprises molybdenum and nickel, and the molar ratio of molybdenum to nickel is 85 to 100:1.

[0012] The hydrodehydration catalyst of the present invention further comprises a modification aid, wherein the modification aid is at least one of iron, cobalt and cerium.

[0013] The hydrodehydration catalyst of the present invention, wherein the active components in the hydrodehydration catalyst are calculated as molybdenum oxide and nickel oxide, and the mass of the active components accounts for 10-30% of the mass of the carrier.

[0014] In the hydrogenation dehydration catalyst of the present invention, the modification aid is calculated as metal oxide, and the modification aid accounts for 0.3-0.7% of the mass of the carrier.

[0015] In order to achieve the above object, the present invention also provides a method for preparing the above-mentioned hydrodehydration catalyst, characterized in that it comprises the following steps:

[0016] Step 1, preparing magnesium aluminum spinel;

[0017] Step 2, the magnesium aluminum spinel, aluminum hydroxide dry glue, and sesbania powder are mixed, an inorganic acid is added to extrudates, and calcined to obtain a carrier;

[0018] Step 3: impregnating the carrier with a solution containing a molybdenum precursor and a nickel precursor to obtain a catalyst.

[0019] The method for preparing the hydrodehydration catalyst of the present invention further comprises the step of impregnating the carrier with an organosilicon solution before impregnating the carrier with the active component; and / or the organosilicon is alkoxysilane.

[0020] The method for preparing the hydrogenation dehydration catalyst of the present invention further comprises the steps of impregnating the catalyst obtained in step 3 with a solution containing a modification aid precursor, followed by drying and calcining.

[0021] The preparation method of the hydrogenation dehydration catalyst of the present invention, wherein the preparation of magnesium aluminum spinel is: a magnesium source, an aluminum source, a complexing agent, and citric acid are mixed and roasted to obtain magnesium aluminum spinel.

[0022] The preparation method of the hydrogenation dehydration catalyst of the present invention, wherein the molybdenum precursor is a molybdenum-containing inorganic salt, the nickel precursor is a nickel-containing inorganic salt; the mass ratio of magnesium aluminum spinel, aluminum hydroxide dry glue, and field sesbania powder is, for example, 5-7:1.2-2.0:0.2-0.4.

[0023] In the method for preparing the hydrogenation dehydration catalyst of the present invention, the modification aid precursor is at least one of an iron salt, a cobalt salt, and a cerium salt.

[0024] Beneficial effects of the present invention:

[0025] The catalyst of the present invention uses magnesium aluminum spinel as a carrier, molybdenum and nickel as active components, and controls the molar ratio of molybdenum to nickel within the range of 85 to 100:1, so that when the catalyst of the present invention is used for preparing normal alkanes from animal and vegetable oils and fats, the conversion rate is high and the selectivity of C18 normal alkanes is high. DETAILED DESCRIPTION

[0026] The technical scheme of the present invention is described in detail below. The following implementation modes are implemented on the premise of the technical scheme 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 implementation modes. The structures or experimental methods of specific conditions are not specified in the following implementation modes, and generally conventional conditions are followed.

[0027] The present invention provides a hydrogenation dehydration catalyst for preparing C16 and C18 normal alkanes from animal and vegetable oils and fats. The hydrogenation dehydration catalyst comprises a carrier and an active component. The carrier comprises magnesium aluminum spinel, and the active component comprises molybdenum and nickel, and the molar ratio of molybdenum to nickel is 85 to 100:1.

[0028] The catalyst of the present invention uses magnesium aluminum spinel as a carrier, molybdenum and nickel as active components, and controls the molar ratio of molybdenum to nickel within the range of 85 to 100:1. Therefore, when the catalyst of the present invention is used for preparing normal alkanes from animal and vegetable oils and fats, the animal and vegetable oils and fats mainly undergo hydrogenation and dehydration reactions, avoiding the occurrence of hydrogenation decarbonylation or decarboxylation side reactions, thereby improving the selectivity of C16 and C18 normal alkanes.

[0029] In detail, there are two ways to hydrodeoxygenate animal and vegetable oils, namely hydrodehydration and hydrodecarbonylation / carboxylation. When hydrodehydration occurs, the oxygen in the fatty acid ester generates water, and the fatty acid carbon chain does not break, generating n-hexadecane and n-octadecane. The yield of n-hexadecane and n-octadecane will be higher. When hydrodecarbonylation / carboxylation occurs, the oxygen in the fatty acid ester generates CO or CO 2 The fatty acid carbon chain ends are broken, and n-pentadecane and n-heptadecane are generated by reaction, and the yields of n-pentadecane and n-heptadecane are higher. The present invention improves the catalyst to make the animal and plant oils mainly undergo hydrogenation and dehydration reaction.

[0030] The present invention does not specifically limit the magnesium-aluminum spinel, and it can be a commercially available product. In one embodiment, the magnesium-aluminum spinel of the present invention is prepared by the following method:

[0031] A magnesium source, an aluminum source, a complexing agent and citric acid are mixed and calcined to obtain magnesium-aluminum spinel.

[0032] The present invention does not specifically limit the magnesium source and the aluminum source. For example, the magnesium source is magnesium nitrate, and the aluminum source is aluminum nitrate. The complexing agent is, for example, dodecyltrimethylammonium bromide, which is not specifically limited in the present invention. In one embodiment, water is further added during the mixing process of the present invention, and the molar ratio of the magnesium source, the aluminum source, the complexing agent, the citric acid and the water is 1:1-3:4-8:0.01-0.05:60-75, and the preferred molar ratio is 1:2:6:0.01:70.

[0033] In one embodiment, the present invention mixes a magnesium source, an aluminum source, a complexing agent, and citric acid, stirs for 2 to 3 hours at 60-90° C. until the solution becomes a gel, then stands at room temperature for a period of time, puts in an oven for aging, and then roasts at 600 to 800° C. to obtain magnesium aluminum spinel. In another embodiment, the roasting temperature is 680-720° C., the heating rate is 2 to 3° C. / min, and the roasting time is 6 to 10 hours.

[0034] In one embodiment, the catalyst carrier of the present invention further comprises alumina, and the preparation method of the carrier comprises: uniformly mixing magnesium aluminum spinel, aluminum hydroxide dry glue, and sesbania powder, then adding inorganic acid to extrude strips, and roasting to obtain the catalyst carrier.

[0035] Among them, the mass ratio of magnesium aluminum spinel, aluminum hydroxide dry glue and sesbania powder is, for example, 5-7:1.2-2.0:0.2-0.4, preferably 6:1.5:0.3, the inorganic acid is, for example, dilute nitric acid, the mass concentration of dilute nitric acid is, for example, 2%, and the ratio of dilute nitric acid to the mixture of magnesium aluminum spinel, aluminum hydroxide dry glue and sesbania powder is, for example, 1.0 mL / g.

[0036] The present invention does not impose any particular limitation on the calcination temperature during the preparation of the catalyst carrier, and the calcination temperature is, for example, 680-720°C.

[0037] In one embodiment, before the active component is loaded on the carrier of the present invention, the further step includes: impregnating the carrier with an organosilicon solution.

[0038] The organosilicon is, for example, alkoxysilane, more preferably tetraethoxysilane. The concentration of the organosilicon solution is, for example, 0.005-0.05 g / ml, preferably 0.01-0.02 g / ml. The impregnation method is, for example, equal volume impregnation, the impregnation temperature is, for example, 20-30° C., the impregnation time is, for example, 20-30 min, and the impregnation is followed by drying, the drying temperature is, for example, 110-150° C., and the drying time is, for example, 3-7 h.

[0039] In the catalyst of the present invention, the active component is loaded on the carrier, the active component includes molybdenum and nickel, and the molar ratio of molybdenum to nickel is 85-100:1.

[0040] The present invention does not particularly limit the manner in which the active component is loaded on the carrier, for example, by impregnation, which may be equal volume impregnation, excess impregnation, etc.

[0041] In one embodiment, the method of loading an active component onto a carrier of the present invention comprises:

[0042] The molybdenum precursor and the nickel precursor are dissolved in water to prepare an impregnation solution, and then the carrier and the impregnation solution are mixed, stirred, dried, and calcined to obtain a catalyst.

[0043] The present invention does not particularly limit the molybdenum precursor and the nickel precursor. In one embodiment, the molybdenum precursor is ammonium molybdate, the nickel precursor is nickel nitrate, and the mass ratio of the impregnation solution to the carrier is 0.5-0.8:1.0. In the present invention, stirring can be performed once every period of time, for example, stirring once every 10-30 minutes, the drying temperature is, for example, 110-150°C, the drying time is, for example, 4-12 hours, the roasting temperature is, for example, 480-650°C, preferably 550-600°C, and the roasting time is, for example, 3-5h.

[0044] In one embodiment, the catalyst of the present invention further comprises a modification aid, wherein the modification aid is at least one of iron, cobalt and cerium. In another embodiment, the modification aid of the present invention is at least two of iron, cobalt and cerium.

[0045] In one embodiment, the carrier of the present invention is loaded with a modifying agent after loading the active component. The following is an exemplary method of loading the modifying agent after loading the active component: the carrier is impregnated with an active component impregnation solution, dried (not calcined), then impregnated with a modifying agent solution, dried, and calcined.

[0046] The modification aid solution is an aqueous solution of a modification aid precursor, wherein the concentration of the modification aid is, for example, 0.50-1.5 mol / L, the precursor of iron is an iron salt, such as iron nitrate, the precursor of cobalt is a cobalt salt, such as cobalt nitrate, and the precursor of cerium is a cerium salt, such as cerium nitrate. The mass ratio of the modification aid solution to the carrier is, for example, 0.5-0.8:1.0, and after impregnation, the catalyst is allowed to stand at room temperature for 8-12 hours, dried at 105-120°C for 3-5 hours, and calcined at 480-650°C, preferably 550-600°C, for 3-5 hours to obtain a catalyst.

[0047] In the catalyst of the present invention, the active components are calculated as molybdenum oxide and nickel oxide, the mass of the active components accounts for 10-30% of the mass of the carrier, preferably 20-25%, and the molybdenum: nickel molar ratio is 85-100:1, for example 87:1, 88:1, 89:1, 90:1, 92:1, 94:1, 95:1. In one embodiment, the carrier is modified with organosilicon, and the mass of the carrier is, for example, the mass of the carrier after the organosilicon modification.

[0048] In one embodiment, in the catalyst of the present invention, the modification aid is calculated as metal oxide, and the modification aid accounts for 0.3-0.7% of the mass of the catalyst.

[0049] The catalyst of the present invention is used to catalyze the hydrogenation and dehydration reaction of animal and vegetable oils to obtain C18 normal alkanes. In one embodiment, the animal and vegetable oils are non-edible vegetable oils and / or waste animal and vegetable oils, which can be directly purchased or obtained by refining the oils as raw materials. The purpose of refining the animal and vegetable oils is to remove impurities such as phosphorus, chlorine, and metals in the animal and vegetable oils.

[0050] In one embodiment, the hydrodehydration reaction is carried out in a fixed bed reactor at a reaction temperature of 320 to 400°C, preferably 350 to 380°C, a reaction pressure of 1 to 4 MPa, preferably 1.5 to 2.5 MPa, and a mass space velocity of 0.5 to 2 h -1 , preferably 0.8 to 1.5 hours -1 , the volume ratio of hydrogen to oil is 100-400:1, preferably 150-300:1.

[0051] In another embodiment, a solvent is further added to the hydrodehydration reaction, and the volume ratio of the solvent to the reaction mixture is 70-95%, preferably 75-90%. Here, the reaction mixture includes reaction raw materials and solvent. The present invention does not specifically limit the solvent, for example, it is n-octadecane or n-hexadecane or the hydrodeoxygenation product in this embodiment.

[0052] The mixture after the hydrogenation and dehydration reaction of the present invention can be first subjected to oil-water separation and then distilled to obtain C18 normal alkanes.

[0053] The catalyst of the invention is used for catalyzing the reaction of animal and plant fats and oils, and can avoid the occurrence of decarbonylation and decarboxylation side reactions during the reaction, thereby improving the selectivity of n-octadecane to produce more n-octadecane, and the selectivity of n-octadecane can be above 96%.

[0054] The technical solution of the present invention will be further described in detail below through specific examples. The reagents and materials, unless otherwise specified, can be obtained from commercial sources.

[0055] Nickel nitrate: Nickel nitrate hexahydrate, Aladdin reagent, AR, 98%

[0056] Molybdenum nitrate: Shanghai Yihe Biotechnology, AR, 99.95%

[0057] Magnesium nitrate: Magnesium nitrate hexahydrate, Tianjin Fuchen, 98%

[0058] Aluminum nitrate: Tianjin Fuchen, 99%

[0059] Citric acid: Jinan Century Tongda, 95%

[0060] Dodecyltrimethylammonium bromide: Aladdin reagent, AR, 98%

[0061] Ferric nitrate: Tianjin Fuchen, 98.5%

[0062] Cobalt nitrate: Guangzhou Deli Chemical, 98%

[0063] Cerium nitrate: Aladdin reagent, 99.5%

[0064] Tetraethoxysilane: Meril, 98%

[0065] Jatropha refined oil: Yunnan Shenyu

[0066] Comparative Example 1

[0067] (1) Weigh a certain amount of NiSO 4 6H 2 O, H 2 MoO 4 ·H 2O, glycolic acid, Mo:Ni molar ratio of 1.0, (Mo+Ni): glycolic acid molar ratio of 0.5, respectively dissolved in a certain amount of 70wt% ethanol aqueous solution, mixed to make the total amount of ethanol aqueous solution 500ml / (Mo+Ni)mol, the solution was mixed evenly and the pH value of the solution was adjusted to 1 with 27wt% ammonia water. Then, hard template polystyrene microspheres were added to the above solution according to the ratio of 40g hard template / (Mo+Ni)mol, mechanically stirred to obtain a suspension, the suspension was placed in a 90℃ water bath and magnetically stirred until a sol was formed, ultrasonically vibrated for 30min, aged at room temperature for 3h, dried at 105℃ to obtain a mixture of dry gel and polystyrene microspheres, and the obtained mixture was calcined at 180℃ for 4h in a nitrogen atmosphere in a tube furnace, and calcined at 700℃ for 2h in an air atmosphere in a muffle furnace to obtain Mo-Ni composite oxide powder. Mo-Ni powder, pseudo-boehmite and polystyrene microspheres (the mass ratio of pseudo-boehmite to polystyrene microspheres is 3:1), and sesbania powder are evenly mixed in a mass ratio of 7:4:0.3, 2wt% dilute nitric acid (1.5ml / (Mo-Ni)g) is added dropwise, and the mixture is extruded into strips with a diameter of 2mm. The strips are calcined at 550°C in an air atmosphere of a muffle furnace for 4h to obtain a bulk Mo-Ni hydrodeoxygenation catalyst.

[0068] (2) Using n-octane solution containing 20% ​​by volume of Jatropha curcas oil as raw material, a continuous flow fixed bed was used at a reaction temperature of 305°C, a reaction pressure of 2.0 MPa, and a reaction space velocity of 2.0 h -1 The hydrodeoxygenation reaction was carried out under the conditions of a hydrogen-to-oil volume ratio of 200:1, and the hydrodeoxygenation product was separated by water. The properties of the raw material Jatropha curcas oil are shown in Table 1, the evaluation results are shown in Table 2, and the composition of the hydrogenation product is shown in Table 3.

[0069] Comparative Example 2

[0070] (1) First, take citric acid and dissolve it in water, then add magnesium nitrate, aluminum nitrate, and dodecyltrimethylammonium bromide in sequence. The molar ratio of magnesium nitrate, aluminum nitrate, dodecyltrimethylammonium bromide, citric acid, and water is 1:2:6:0.01:70. Stir for 2 to 3 hours at 80°C until the solution becomes a gel. Let it stand at room temperature for 1 hour, then put it in an oven for aging. Calcinate in a muffle furnace at 700°C, with a heating rate of 2 to 3°C / min, and calcine for 6 to 10 hours to obtain magnesium aluminum spinel.

[0071] Magnesium aluminum spinel powder, aluminum hydroxide dry glue, and sesbania powder were mixed evenly at a mass ratio of 8:2:0.3, and 0.8 mL / g MgAl 2 O 4 The catalyst carrier was prepared by dropping 4% dilute nitric acid into powder and then extruding it into strips. The catalyst carrier was calcined in a muffle furnace at 400°C for 6h to obtain the catalyst carrier.

[0072] (2) Weigh a certain amount of C in proportion4 H 6 O 4 Ni·4H 2 O.Mo(NO 3 ) 3 ·5H 2 O, malic acid, the active component (Mo+Ni) is added in an amount of 20% of the carrier mass, calculated as the mass of MoO3+NiO, the molar ratio of Mo:Ni is 5, the molar ratio of (Mo+Ni):malic acid is 1.5:1, dissolved in deionized water, the mass ratio of the deionized water solution to the carrier is 0.7:1, the active component is loaded by an equal volume impregnation method, allowed to stand at 30°C for 10 h, dried at 110°C for 4 h in a muffle furnace and calcined at 600°C for 3.5 h to obtain the desired catalyst.

[0073] (3) Catalyst evaluation

[0074] Using n-octane solution containing 20% ​​tung oil by volume as raw material, a continuous fixed bed was used at a temperature of 370°C, a pressure of 2 MPa, and a space velocity of 1.0 h -1 Under the conditions of hydrogen-to-oil volume ratio of 200:1, the hydrodeoxygenation reaction was carried out, and the hydrodeoxygenation product was separated by water. The properties of the raw material tung oil are shown in Table 1, the evaluation results are shown in Table 2, and the composition of the hydrogenated product is shown in Table 3.

[0075] Example 1

[0076] (1) Preparation of carrier

[0077] First, take citric acid and dissolve it in water, then add magnesium nitrate, aluminum nitrate, and dodecyl trimethyl ammonium bromide in turn. The molar ratio of magnesium nitrate, aluminum nitrate, dodecyl trimethyl ammonium bromide, citric acid, and water is 1:2:6:0.01:70. Stir for 2 to 3 hours at 80°C until the solution becomes a gel. Let it stand at room temperature for 1 hour, then put it in an oven for aging. Calcinate in a muffle furnace at 700°C, with a heating rate of 2 to 3°C / min, and calcine for 6 to 10 hours to obtain magnesium aluminum spinel.

[0078] Magnesium aluminum spinel powder, aluminum hydroxide dry glue and sesbania powder were mixed evenly at a mass ratio of 6:1.2:0.2, and diluted nitric acid with a mass concentration of 2% was added at a liquid-solid ratio of 1.0 mL / g. Then, strips were extruded and calcined at 700° C. in a muffle furnace for 2 h to obtain a catalyst carrier.

[0079] (2) Carrier modification

[0080] Add tetraethoxysilane to water at a concentration of 0.005 g / ml. Use equal volume impregnation method to impregnate the catalyst support with the solution. After impregnation for 30 minutes, dry in an oven at 115°C for 12 hours.

[0081] (3) Active ingredient loading

[0082] First, molybdenum nitrate and nickel nitrate are dissolved in water to prepare an impregnation solution, in which the active component is MoO 3 The mass of +NiO is 20% of the mass of the carrier, the molybdenum: nickel molar ratio is 95; the mass ratio of the impregnation solution to the carrier is 0.7: 1. After the impregnation is completed, it is allowed to stand at room temperature for 12 hours and dried in an oven at 115°C for 12 hours.

[0083] (4) Additive loading

[0084] A mixed solution of ferric nitrate + cobalt nitrate was prepared from liquid, the concentration of ferric nitrate was 0.5 mol / L, and the concentration of cobalt nitrate was 0.6 mol / L, and it was impregnated on the catalyst carrier, the mass ratio of solution to carrier was 0.5:1. After the impregnation was completed, it was allowed to stand at room temperature for 10 hours, dried at 110°C in a muffle furnace for 4 hours, and calcined at 600°C for 4 hours to obtain the desired catalyst.

[0085] (5) Catalyst evaluation

[0086] The refined Jatropha curcas oil was mixed with a solvent and subjected to a hydrogenation dehydration reaction in a fixed bed reactor under the action of the above catalyst at a reaction temperature of 360°C, a reaction pressure of 1.0 MPa, and a reaction mass space velocity of 1.8 h -1 , the volume ratio of hydrogen to oil is 130:1, the volume ratio of solvent to reaction mixture is 80%, the hydrogenation dehydration product is subjected to water separation, the properties of raw material Jatropha curcas oil are shown in Table 1, the evaluation results are shown in Table 2, and the composition of hydrogenation product is shown in Table 3.

[0087] Example 2

[0088] (1) According to Example 1, a carrier was prepared.

[0089] (2) Carrier modification

[0090] Tetraethoxysilane was added to water at a concentration of 0.04 g / ml. The solution was impregnated onto the support using an equal volume impregnation method. After impregnation for 30 minutes, the support was dried at 120°C for 5 hours to obtain the final support.

[0091] (3) Active ingredient loading

[0092] First, molybdenum nitrate and nickel nitrate are dissolved in water to prepare an impregnation solution, in which the active component is MoO 3 The mass of +NiO is 20% of the mass of the carrier, the molybdenum: nickel molar ratio is 95; the mass ratio of the impregnation solution to the carrier is 0.7: 1. After the impregnation is completed, it is allowed to stand at room temperature for 12 hours and dried in an oven at 115°C for 12 hours.

[0093] (4) Additive loading

[0094] A cerium nitrate solution was prepared with a concentration of 0.5 mol / L, and impregnated onto the catalyst carrier with a mass ratio of solution to carrier of 0.5:1. After impregnation, the solution was allowed to stand at room temperature for 10 h, dried at 110°C for 4 h in a muffle furnace, and calcined at 600°C for 4 h to obtain the desired catalyst.

[0095] (5) Catalyst evaluation

[0096] Jatropha curcas refined oil was mixed with a solvent and subjected to a hydrogenation dehydration reaction in a fixed bed reactor under the action of a hydrogenation deoxygenation catalyst at a reaction temperature of 370°C, a reaction pressure of 4.0 MPa, and a reaction mass space velocity of 1.2 h -1 , hydrogen-oil volume ratio is 400:1, the volume of solvent accounts for 70% of the reaction mixture, the hydrogenation dehydration product is separated by water, the properties of the raw material tung oil are shown in Table 1, the evaluation results are shown in Table 2, and the composition of the hydrogenation product is shown in Table 3.

[0097] Example 3

[0098] (1) According to Example 1, a carrier was prepared.

[0099] (2) Carrier modification

[0100] Tetraethoxysilane was added to water at a concentration of 0.05 g / ml. The solution was impregnated onto the support using an equal volume impregnation method. After impregnation for 30 minutes, the support was dried at 120°C for 5 hours to obtain the final support.

[0101] (3) Active ingredient loading

[0102] First, nickel nitrate and molybdenum nitrate are prepared to obtain an impregnation solution, wherein the active component is MoO 3 The mass of +NiO is 20% of the mass of the carrier, the molar ratio of molybdenum to nickel is 100, and the mass ratio of the impregnation solution to the carrier is 0.7: 1. After the impregnation is completed, it is allowed to stand at room temperature for 12 hours and dried in an oven at 115°C for 12 hours.

[0103] (4) Additive loading

[0104] A mixed solution of ferric nitrate + cobalt nitrate was prepared, the concentration of ferric nitrate was 0.7 mol / L, and the concentration of cobalt nitrate was 0.8 mol / L, and impregnated onto the catalyst carrier, the mass ratio of solution to carrier was 0.5:1. After impregnation, it was allowed to stand at room temperature for 10 h, dried in a muffle furnace at 110 °C for 4 h, and calcined at 600 °C for 4 h to obtain the desired catalyst.

[0105] (5) Catalyst evaluation

[0106] Jatropha curcas refined oil was mixed with a solvent and subjected to a hydrogenation dehydration reaction in a fixed bed reactor under the action of a hydrogenation deoxygenation catalyst at a reaction temperature of 390°C, a reaction pressure of 3MPa, and a reaction mass space velocity of 2.0h -1 , the volume ratio of hydrogen to oil is 100:1, the volume ratio of solvent is 90%, the hydrogenation and dehydration products are separated by water, the properties of the raw material tung oil are shown in Table 1, the evaluation results are shown in Table 2, and the composition of the hydrogenation products is shown in Table 3.

[0107] Example 4

[0108] (1) According to Example 1, a carrier was prepared.

[0109] (2) Carrier modification

[0110] Tetraethoxysilane was added to water at a concentration of 0.01 g / ml. The solution was impregnated onto the support using an equal volume impregnation method. After impregnation for 30 minutes, the support was dried at 120°C for 5 hours to obtain the final support.

[0111] (3) Active ingredient loading

[0112] First, molybdenum nitrate and nickel nitrate are dissolved in water to prepare an impregnation solution, in which the active component is MoO 3 The mass of +NiO is 20% of the mass of the carrier, the molybdenum: nickel molar ratio is 85; the mass ratio of the impregnation solution to the carrier is 0.7: 1. After the impregnation is completed, it is allowed to stand at room temperature for 12 hours and dried in an oven at 115°C for 12 hours.

[0113] (4) Additive loading

[0114] A mixed solution of ferric nitrate + cerium nitrate was prepared, the concentration of ferric nitrate was 0.8 mol / L, the concentration of cerium nitrate was 0.5 mol / L, and it was impregnated onto the catalyst carrier. The mass ratio of the solution to the carrier was 0.5:1. After the impregnation was completed, it was allowed to stand at room temperature for 10 hours, dried in a muffle furnace at 110°C for 4 hours, and calcined at 600°C for 4 hours to obtain the desired catalyst.

[0115] (5) Catalyst evaluation

[0116] Jatropha curcas refined oil was mixed with a solvent and subjected to a hydrogenation dehydration reaction in a fixed bed reactor under the action of a hydrogenation deoxygenation catalyst at a reaction temperature of 360°C, a reaction pressure of 1.5 MPa, and a reaction mass space velocity of 0.9 h -1 , hydrogen-to-oil volume ratio is 170:1, the volume of solvent accounts for 75% of the reaction mixture, the hydrogenation and dehydration product is separated by water, the properties of the raw material Jatropha curcas oil are shown in Table 1, the evaluation results are shown in Table 2, and the composition of the hydrogenation product is shown in Table 3.

[0117] Example 5

[0118] (1) According to Example 4, the carrier preparation and carrier modification were carried out.

[0119] (2) Active ingredient loading

[0120] First, molybdenum nitrate and nickel nitrate are dissolved in water to prepare an impregnation solution, in which the active component is MoO 3 The mass of +NiO is 20% of the mass of the carrier, the molybdenum: nickel molar ratio is 90; the mass ratio of the impregnation solution to the carrier is 0.7: 1. After the impregnation is completed, it is allowed to stand at room temperature for 12 hours and dried in an oven at 115°C for 12 hours.

[0121] (3) Additive loading

[0122] A mixed solution of ferric nitrate + cerium nitrate was prepared, the concentration of ferric nitrate was 1.0 mol / L, the concentration of cerium nitrate was 0.5 mol / L, and it was impregnated onto the catalyst carrier. The mass ratio of the solution to the carrier was 0.5:1. After the impregnation was completed, it was allowed to stand at room temperature for 10 hours, dried in a muffle furnace at 110°C for 4 hours, and calcined at 600°C for 4 hours to obtain the desired catalyst.

[0123] (4) Catalyst evaluation

[0124] Jatropha curcas refined oil was mixed with a solvent and subjected to a hydrogenation dehydration reaction in a fixed bed reactor under the action of a hydrogenation deoxygenation catalyst at a reaction temperature of 370°C, a reaction pressure of 2.0 MPa, and a reaction mass space velocity of 1.0 h -1 , the volume ratio of hydrogen to oil is 200:1, the volume of solvent accounts for 80% of the reaction mixture, the hydrogenation dehydration product is separated by water, the properties of the raw material Jatropha curcas oil are shown in Table 1, the evaluation results are shown in Table 2, and the composition of the hydrogenation product is shown in Table 3.

[0125] Example 6

[0126] (1) According to Example 1, a carrier was prepared.

[0127] (2) Carrier modification

[0128] Tetraethoxysilane was added to water at a concentration of 0.02 g / ml. The solution was impregnated onto the support using an equal volume impregnation method. After impregnation for 30 minutes, the support was dried at 120°C for 5 hours to obtain the final support.

[0129] (3) Active ingredient loading

[0130] First, molybdenum nitrate and nickel nitrate are dissolved in water to prepare an impregnation solution, in which the active component is MoO 3 The mass of +NiO is 20% of the mass of the support, the molybdenum: nickel molar ratio is 85, and the mass ratio of the impregnation solution to the support is 0.7: 1. After the impregnation is completed, it is allowed to stand at room temperature for 12 hours and dried in an oven at 115°C for 12 hours.

[0131] (4) Additive loading

[0132] A mixed solution of ferric nitrate + cerium nitrate was prepared, the concentration of ferric nitrate was 0.6 mol / L, the concentration of cerium nitrate was 0.6 mol / L, and it was impregnated onto the catalyst carrier. The mass ratio of the solution to the carrier was 0.5:1. After the impregnation was completed, it was allowed to stand at room temperature for 10 hours, dried in a muffle furnace at 110°C for 4 hours, and calcined at 600°C for 4 hours to obtain the desired catalyst.

[0133] (5) Catalyst evaluation

[0134] Jatropha curcas refined oil was mixed with a solvent and subjected to a hydrogenation dehydration reaction in a fixed bed reactor under the action of a hydrogenation deoxygenation catalyst at a reaction temperature of 355°C, a reaction pressure of 2.0 MPa, and a reaction mass space velocity of 1.1 h -1 , the volume ratio of hydrogen to oil is 180:1, the volume of solvent accounts for 90% of the reaction mixture, the hydrogenation and dehydration product is separated by water, the properties of the raw material tung oil are shown in Table 1, the evaluation results are shown in Table 2, and the composition of the hydrogenation product is shown in Table 3.

[0135] Example 7

[0136] (1) According to Example 6, a carrier was prepared and modified.

[0137] (2) Active ingredient loading

[0138] First, molybdenum nitrate and nickel nitrate are dissolved in water to prepare an impregnation solution, in which the active component is MoO 3 The mass of +NiO is 20% of the mass of the support, the molybdenum: nickel molar ratio is 90, and the mass ratio of the impregnation solution to the support is 0.7: 1. After the impregnation is completed, it is allowed to stand at room temperature for 12 hours and dried in an oven at 115°C for 12 hours.

[0139] (3) Additive loading

[0140] A mixed solution of ferric nitrate and cerium nitrate was prepared, with the concentration of ferric nitrate being 0.9 mol / L and the concentration of cerium nitrate being 0.6 mol / L. The solution was impregnated onto a catalyst carrier with a mass ratio of solution to carrier being 0.5:1. The solution was allowed to stand at room temperature for 10 h, dried in a muffle furnace at 110°C for 4 h, and calcined at 600°C for 4 h to obtain the desired catalyst.

[0141] (4) Catalyst evaluation

[0142] Jatropha curcas refined oil was mixed with a solvent and subjected to a hydrogenation dehydration reaction in a fixed bed reactor under the action of a hydrogenation deoxygenation catalyst at a reaction temperature of 365°C, a reaction pressure of 2.5 MPa, and a reaction mass space velocity of 1.3 h -1, hydrogen-to-oil volume ratio 210:1, solvent volume ratio of the reaction mixture is 80%, the hydrodeoxygenation product is separated by water, the properties of the raw material tung oil are shown in Table 1, the evaluation results are shown in Table 2, and the composition of the hydrogenated product is shown in Table 3.

[0143] Example 8

[0144] (1) According to Example 1, a carrier was prepared.

[0145] (2) Carrier modification

[0146] Tetraethoxysilane was added to water at a concentration of 0.01 g / ml. The solution was impregnated onto the support by an equal volume impregnation method. After impregnation for 30 minutes, the support was dried at 120°C for 5 hours to obtain the final support.

[0147] (3) Active component loading

[0148] First, molybdenum nitrate and nickel nitrate are dissolved in water to prepare an impregnation solution, in which the active component is MoO 3 The mass of +NiO is 20% of the mass of the support, the molybdenum: nickel molar ratio is 90, and the mass ratio of the impregnation solution to the support is 0.7: 1. After the impregnation is completed, it is allowed to stand at room temperature for 12 hours and dried in an oven at 115°C for 12 hours.

[0149] (4) Additive loading

[0150] A mixed solution of ferric nitrate and cerium nitrate was prepared, the concentration of ferric nitrate was 0.5 mol / L, the concentration of cerium nitrate was 0.8 mol / L, and impregnated onto the catalyst carrier with a mass ratio of solution to carrier of 0.5:1. The solution was allowed to stand at room temperature for 10 h, dried in a muffle furnace at 110°C for 4 h, and calcined at 600°C for 4 h to obtain the desired catalyst.

[0151] (5) Catalyst evaluation

[0152] Jatropha curcas refined oil was mixed with a solvent and subjected to a hydrogenation dehydration reaction in a fixed bed reactor under the action of a hydrogenation deoxygenation catalyst at a reaction temperature of 360°C, a reaction pressure of 2.5 MPa, and a reaction mass space velocity of 0.9 h -1 , hydrogen-to-oil volume ratio is 250:1, the volume of solvent accounts for 75% of the reaction mixture, the hydrogenation dehydration product is separated by water, the properties of the raw material tung oil are shown in Table 1, the evaluation results are shown in Table 2, and the composition of the hydrogenation product is shown in Table 3.

[0153] Example 9

[0154] (1) According to Example 8, a carrier is prepared, the carrier is modified, and the molybdenum-nickel metal component is loaded.

[0155] (2) Additive loading

[0156] A mixed solution of ferric nitrate + cerium nitrate was prepared, the concentration of ferric nitrate was 0.4 mol / L, the concentration of cerium nitrate was 1.0 mol / L, and it was impregnated onto the catalyst carrier. The mass ratio of the solution to the carrier was 0.5:1. After the impregnation was completed, it was allowed to stand at room temperature for 10 hours, dried in a muffle furnace at 110°C for 4 hours, and calcined at 600°C for 4 hours to obtain the desired catalyst.

[0157] (3) Catalyst evaluation

[0158] Jatropha curcas refined oil was mixed with a solvent and subjected to a hydrogenation dehydration reaction in a fixed bed reactor under the action of a hydrogenation deoxygenation catalyst at a reaction temperature of 380°C, a reaction pressure of 2.0 MPa, and a reaction mass space velocity of 1.4 h -1 , the volume ratio of hydrogen to oil is 180:1, the volume of solvent accounts for 85% of the reaction mixture, the hydrogenation and dehydration product is separated by water, the properties of the raw material tung oil are shown in Table 1, the evaluation results are shown in Table 2, and the composition of the hydrogenation product is shown in Table 3.

[0159] Example 10

[0160] (1) First, take citric acid and dissolve it in water, then add magnesium nitrate, aluminum nitrate, and dodecyltrimethylammonium bromide in sequence. The molar ratio of magnesium nitrate, aluminum nitrate, dodecyltrimethylammonium bromide, citric acid, and water is 1:2:6:0.01:70. Stir for 2 to 3 hours at 80°C until the solution becomes a gel. Let it stand at room temperature for 1 hour, then put it in an oven for aging. Calcinate in a muffle furnace at 700°C, with a heating rate of 2 to 3°C / min, and calcine for 6 to 10 hours to obtain magnesium aluminum spinel.

[0161] Magnesium aluminum spinel powder, aluminum hydroxide dry glue, and sesbania powder were mixed evenly at a mass ratio of 8:2:0.3, and the mixture was heated to 1.2 mL / g MgAl 2 O 4 The catalyst carrier was prepared by dropping 2% dilute nitric acid into powder and then extruding it into strips. The catalyst carrier was calcined in a muffle furnace at 800°C for 2h.

[0162] (2) Weigh a certain amount of NiSO 4 6H 2 O、(NH 4 )6Mo 7 O 24 ·4H 2 O, glycolic acid, the amount of active component (Mo+Ni) added is MoO 3The mass of +NiO is calculated as 20% of the mass of the carrier, the molar ratio of Mo:Ni is 90, the molar ratio of (Mo+Ni):glycolic acid is 0.3:1, dissolved in deionized water, the mass ratio of deionized water solution to the carrier is 0.7:1, the active component is loaded by equal volume impregnation method, left to stand at 20°C for 12h, dried in an oven at 110°C for 12h. Calcinated at 480°C for 5h to prepare the desired catalyst.

[0163] (3) Evaluation of catalyst

[0164] The evaluation raw materials and evaluation conditions were the same as those of Comparative Example 2. The properties of the raw material Jatropha curcas oil are shown in Table 1, the evaluation results are shown in Table 2, and the composition of the hydrogenated product is shown in Table 3.

[0165] Embodiment 11

[0166] (1) First, take citric acid and dissolve it in water, then add magnesium nitrate, aluminum nitrate, and dodecyltrimethylammonium bromide in sequence. The molar ratio of magnesium nitrate, aluminum nitrate, dodecyltrimethylammonium bromide, citric acid, and water is 1:2:6:0.01:70. Stir for 2 to 3 hours at 80°C until the solution becomes a gel. Let it stand at room temperature for 1 hour, then put it in an oven for aging. Calcinate in a muffle furnace at 700°C, with a heating rate of 2 to 3°C / min, and calcine for 6 to 10 hours to obtain magnesium aluminum spinel.

[0167] Magnesium aluminum spinel powder, aluminum hydroxide dry glue, and sesbania powder were mixed evenly at a mass ratio of 8:2:0.3, and the mixture was heated to 1.2 mL / g MgAl 2 O 4 The catalyst carrier was prepared by dropping 2% dilute nitric acid into powder and then extruding it into strips. The catalyst carrier was calcined in a muffle furnace at 800°C for 2h.

[0168] (2) Weigh a certain amount of NiSO 4 6H 2 O、(NH 4 )6Mo 7 O 24 ·4H 2 O, glycolic acid, the amount of active component (Mo+Ni) added is MoO 3 The mass of +NiO is calculated as 20% of the mass of the carrier, the molar ratio of Mo:Ni is 90, the molar ratio of (Mo+Ni):glycolic acid is 0.3:1, dissolved in deionized water, the mass ratio of deionized water solution to the carrier is 0.7:1, the active component is loaded by equal volume impregnation method, left to stand at 20°C for 12h, and dried in an oven at 110°C for 12h. The 1.5mol / L ferric nitrate solution is impregnated on the carrier loaded with the active component, the mass ratio of the solution to the carrier is 0.5:1, left to stand at 15°C for 10h, dried at 120°C for 3h and calcined at 480°C for 5h in a muffle furnace to prepare the desired catalyst.

[0169] (3) Evaluation of catalyst

[0170] The evaluation raw materials and evaluation conditions were the same as those of Comparative Example 2. The properties of the raw material Jatropha curcas oil are shown in Table 1, the evaluation results are shown in Table 2, and the composition of the hydrogenated product is shown in Table 3.

[0171] Calculation method of hydrogenation dehydration rate in Table 2:

[0172] In view of the fact that the total amount of C18 acid esters in Jatropha curcas oil is about 83.15ω%, and the total amount of C17 acid esters is about 0.02ω%, when calculating the hydrogenation dehydration rate, the default is that C17 acid esters are zero, and the C17 normal alkanes generated by hydrogenation dehydration of C17 acid esters are defaulted to zero. The C17 normal alkanes in the product are all generated by decarbonylation and decarboxylation of C18 acid esters, that is:

[0173]

[0174] Table 1 Composition of refined jatropha oil

[0175]

[0176] Note: Lauric acid (C12:0) refers to lauric acid without carbon-carbon double bonds, and linolenic acid (C18:3) refers to linolenic acid with three carbon-carbon double bonds.

[0177]

[0178]

[0179] The higher the hydrogenation dehydration rate, the lower the probability of hydrogenation decarbonylation and decarboxylation side reactions, which means that the carbon chain end in the product is broken to generate CO. 2 The lower the molybdenum content and the lower the CO content, the higher the composition of C16 and C18 normal alkanes in the product. The purpose of the present invention is to increase the hydrogenation dehydration rate and the yield of the target product C16 and C18 normal alkanes. As shown in Tables 2 and 3, in Comparative Example 1, the molybdenum / nickel molar ratio is 1, and the active component is MoO 3The mass of +NiO accounts for about 70% of the mass of the catalyst (the active component content is too high, resulting in high cost), and no silicon modification and auxiliary agent modification are performed, and the hydrodehydration rate is 89.5%; in Comparative Example 2, the molybdenum / nickel molar ratio is 5, no silicon modification is performed, no auxiliary agent modification is performed, and the hydrodehydration rate is only 18.9%, and the dehydration selectivity is the worst; in Example 10, the molybdenum / nickel molar ratio is 90, no silicon modification is performed, no auxiliary agent modification is performed, and the hydrodehydration rate is increased by only 59.7%; in Example 11, the molybdenum / nickel molar ratio is 90, and only iron auxiliary agent modification is performed, and the hydrodehydration rate is 91.8%, and the hydrodehydration rate is greatly improved, indicating that the auxiliary agent and the molybdenum / nickel molar ratio can improve the hydrodehydration rate to some extent. Therefore, in the embodiment, the molybdenum / nickel molar ratio, the type of auxiliary agent (silicon, iron, cerium, cobalt), and the auxiliary agent concentration are adjusted, and the hydrodehydration rate is significantly improved. Finally, in Example 5, at a molybdenum / nickel molar ratio of 90, after silicon modification and ferrocerium modification, the hydrogenation dehydration rate reached 97.2%, the C18 normal alkane content in the product reached 80.41%, and the C16 normal alkane content reached 14.04%.

[0180] The present invention can control the occurrence of side reactions and improve the selectivity of target products by adjusting the molybdenum-nickel ratio in the catalyst and adding a modifying agent. The obtained C18 normal alkanes have high purity and extremely low impurity contents such as sulfur and nitrogen aromatics, thereby avoiding the problems of complex production process and harsh process conditions in the production of normal alkanes from traditional fossil raw materials.

[0181] Therefore, the catalyst of the present invention uses magnesium aluminum spinel as a carrier, molybdenum and nickel as active components, and controls the molar ratio of molybdenum to nickel within the range of 85 to 100:1. The catalyst of the present invention is used to catalyze the hydrogenation and dehydration of animal and vegetable oils to generate normal alkanes. The conversion rate reaches 100%, and the selectivity of C18 normal alkanes can be improved. Furthermore, by using silicon, iron, cobalt, and cerium additives to modify the carrier and the catalyst, the selectivity of the target product C18 normal alkanes can be further improved, the decarbonylation and decarboxylation reactions can be reduced, and the generation of by-products can be reduced. At the same time, the content of the target product in the product is increased, and the subsequent separation pressure can be reduced.

[0182] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, technicians familiar with the field may make various corresponding changes and deformations based on the present invention, but these corresponding changes and deformations should all fall within the scope of protection of the claims of the present invention.

Claims

1. A hydrodehydration catalyst, characterized in that: Used for preparing C16 and C18 normal alkanes from animal and plant oils and fats, the hydrogenation dehydration catalyst comprises a carrier and an active component, the carrier comprises magnesium aluminum spinel, the active component comprises molybdenum and nickel, and the molar ratio of molybdenum to nickel is 85 to 100:

1.

2. The hydrodehydration catalyst according to claim 1, characterized in that It also includes a modification aid, which is at least one of iron, cobalt and cerium.

3. The hydrodehydration catalyst according to claim 1, characterized in that In the hydrodehydration catalyst, the active components are calculated as molybdenum oxide and nickel oxide, and the mass of the active components accounts for 10-30% of the mass of the carrier.

4. The hydrodehydration catalyst according to claim 2, characterized in that The modification aid is calculated as metal oxide, and the modification aid accounts for 0.3-0.7% of the mass of the catalyst.

5. The method for preparing the hydrodehydration catalyst according to any one of claims 1 to 4, characterized in that: The steps include: Step 1, preparing magnesium aluminum spinel; Step 2, the magnesium aluminum spinel, aluminum hydroxide dry glue, and sesbania powder are mixed, an inorganic acid is added to extrudates, and calcined to obtain a carrier; Step 3: impregnating the carrier with a solution containing a molybdenum precursor and a nickel precursor to obtain a catalyst.

6. The method for preparing the hydrodehydration catalyst according to claim 5, characterized in that: Before the carrier is impregnated with the active component, the method further includes impregnating the carrier with an organic silicon solution; and / or the organic silicon is alkoxysilane.

7. The method for preparing the hydrodehydration catalyst according to claim 5, characterized in that: The method also includes the steps of impregnating the catalyst obtained in step 3 with a solution containing a modification aid precursor, and then drying and calcining.

8. The method for preparing the hydrodehydration catalyst according to claim 5, characterized in that: The method for preparing the magnesium-aluminum spinel comprises: mixing a magnesium source, an aluminum source, a complexing agent and citric acid, and calcining the mixture to obtain the magnesium-aluminum spinel.

9. The method for preparing a hydrodehydration catalyst according to claim 5, characterized in that: The molybdenum precursor is an inorganic salt containing molybdenum, and the nickel precursor is an inorganic salt containing nickel; the mass ratio of magnesium aluminum spinel, aluminum hydroxide dry glue, and sesbania powder is, for example, 5-7:1.2-2.0:0.2-0.

4.

10. The method for preparing a hydrodehydration catalyst according to claim 7, characterized in that: The modification aid precursor is at least one of iron salt, cobalt salt and cerium salt.

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