Hydrodeoxygenation catalyst for oils and fats, and preparation method therefor and use thereof

Abstract

A hydrodeoxygenation catalyst for oils and fats, and a preparation method therefor and the use thereof. The preparation method comprises: mixing an aluminum-containing inorganic porous material, an acidic solution, an extrusion aid, a magnesium salt and a nickel salt, then subjecting same to extrusion molding to obtain a carrier precursor, and drying and roasting the carrier precursor to obtain a hydrodeoxygenation composite carrier; and impregnating an impregnation solution containing an active metal onto the hydrodeoxygenation composite carrier, and then drying and roasting same to obtain a hydrodeoxygenation catalyst for oils and fats. When preparing a hydrodeoxygenation composite carrier in the present invention, a magnesium salt and a nickel salt are used in combination to obtain a hydrodeoxygenation composite carrier having a nickel-doped magnesium aluminum spinel structure. The hydrodeoxygenation composite carrier has good hydrothermal stability and mechanical strength. The hydrodeoxygenation catalyst for oils and fats, which is prepared by loading an active metal component on the hydrodeoxygenation composite carrier, has stable deoxygenation activity and an excellent deoxygenation effect.

Description

A catalyst for the hydrodeoxygenation of oils and fats, its preparation method and application

[0001] This application claims priority to Chinese Patent Application No. 202411523605.9, filed on October 29, 2024, entitled "A Catalyst for Hydrogenation Deoxygenation of Oils and Fats and Its Preparation Method and Application", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This invention relates to a catalyst for the hydrogenation and deoxygenation of oils and fats, its preparation method and application, belonging to the field of bio-oil deoxygenation and hydrogenation technology. Background Technology

[0003] Currently, renewable energy is being widely promoted and applied, and clean technologies are developing rapidly. Major industries such as power, industry, construction, and transportation have made significant progress in energy conservation and emission reduction. As a part of the transportation sector, the aviation industry has received increasing attention in terms of emission reduction. Compared with other industries, the aviation industry has relatively limited options for emission reduction plans and pathways, making emission reduction more difficult, and is therefore known as one of the "difficult-to-reduce" sectors.

[0004] The main ways to reduce emissions in the aviation industry include energy efficiency improvement and clean energy substitution. Since the carbon emission base of the aviation sector is relatively large, the carbon emission reduction that can be achieved by improving energy efficiency is relatively limited. Sustainable aviation kerosene, with its high calorific value and zero emissions, brings new possibilities and prospects for emission reduction in the aviation industry.

[0005] There are four main production technologies for sustainable jet fuel: hydroprocessed esters and fatty acids (HEFA), gasification / Fischer-Tropsch synthesis, alcohol-to-jet, and power-to-liquid technology. Currently, most sustainable jet fuel producers use the HEFA route, while the other three technologies, due to their immature technology or supply chains, only exist in small-scale or experimental production projects.

[0006] Oil hydrotreating is the first generation of truly "sustainable" aviation kerosene production technology. The hydrotreating process of bio-oils utilizes hydrodeoxygenation catalysts. Because bio-oils contain a significant amount of oxygen, most of this oxygen is removed as water during hydrodeoxygenation. Prolonged exposure to high-temperature, water vapor can damage the catalyst's pore structure, leading to activity loss or deactivation. Therefore, the hydrothermal stability of the bio-oil hydrodeoxygenation catalyst support is a crucial factor determining whether the catalyst can maintain stable deoxygenation activity over a long period. Current research on the hydrothermal stability of hydrodeoxygenation supports and catalysts is limited. Hydrodeoxygenation catalysts exhibit varying degrees of poor hydrothermal stability during long-term operation, leading to decreased activity or deactivation as the catalyst's service life increases.

[0007] The applicant will provide some prior art related to this invention to enable those skilled in the art to better understand the situation of the prior art.

[0008] CN117983291A discloses a catalyst for the hydrodeoxyisomeric preparation of alkanes via oil and fat, its preparation method, and its uses. The catalyst comprises, by weight percentage, 10-40% Ni, 0.1-5% of at least one oxide selected from Group VIB metals, and 55-85% of a composite support containing SiO2, Al2O3, and SAPO11 molecular sieves. The catalyst uses a mixture of alumina sol, silica sol, and SAPO11 molecular sieves as a precursor. A required amount of nickel-ammonia complex and a solution of a Group VIB metal or its oxide are added to the precursor to obtain a mixture. The mixture is then aged at 90-120°C for 20-60 hours. The catalyst is then prepared through washing, drying, and calcination.

[0009] CN117463311A discloses a catalyst support, a hydrogenation catalyst, its preparation method, and its application. The preparation method of the catalyst support includes using a titanium-silicon composite oxide as the support component. The silicon oxide component is derived from both a solid inorganic silicon source and a liquid inorganic silicon source. The combination of the solid and liquid silicon sources, along with the addition of a solid inorganic titanium source, helps to improve the support's strength while simultaneously increasing its specific surface area and pore volume, as well as its average pore size and acid resistance.

[0010] CN117101715A discloses an amine-modified bimetallic supported catalyst, its preparation method, and its application in the synthesis of aviation fuel from oils and fats. The preparation method includes: mixing a nickel source, a molybdenum source, citric acid, and an amine, adding ethanol to form a solution, then adding SAPO11 molecular sieve to the solution and stirring until homogeneous to obtain a reaction solution; stirring the reaction solution at 40-60℃, then stirring at 80℃ until all the ethanol evaporates, and drying in an oven to obtain a catalyst precursor; finally, calcining the catalyst precursor to obtain the amine-modified bimetallic supported catalyst. Using this catalyst in the synthesis of aviation fuel from oils and fats eliminates the need for pre-reduction and pre-sulfurization. Furthermore, this catalyst exhibits high catalytic activity and good anti-carbon deposition performance in the hydrodeoxygenation reaction of oils and fats, and high selectivity for alkane products in the aviation fuel stage.

[0011] CN106268937A discloses a method for preparing a hydrodeoxygenation and hydroisomerization catalyst for the preparation of bio-aviation kerosene from linseed mustard oil. The hydrodeoxygenation catalyst is prepared using modified SBA-15 as a support, Ni-Mo or Ni-Co as the active component, and polyethylene glycol 200 as a dispersant. The hydroisomerization catalyst is prepared using hierarchical porous NiAPO-I1, hierarchical porous NiSAPO-11, hierarchical porous SAPO-11, microporous NiAPO11 or microporous NiSAPO-11 as a support, and Pd or Pt as the active component.

[0012] CN117229804A discloses a method for preparing bio-jet fuel by hydrogenating waste oil. The hydrogenation deoxygenation catalyst used is a spherical Ni-Mo / Al2O3 catalyst. The preparation method includes mixing nickel nitrate and ammonium molybdate evenly in water, adding citric acid, spray granulating through a spray dryer, and loading the impregnation solution onto an alumina support to obtain spherical Ni-Mo composite oxide powder.

[0013] The hydrodeoxygenation supports and catalysts prepared by the above-mentioned existing technologies all suffer from varying degrees of deterioration in hydrothermal stability and / or decrease or deactivation of catalyst activity after long-term operation.

[0014] Therefore, providing a novel catalyst for the hydrodeoxygenation of oils and fats, its preparation method, and its application has become a pressing technical problem that needs to be solved in this field. Summary of the Invention

[0015] To address the aforementioned shortcomings and deficiencies, the present invention aims to provide a hydrodeoxygenation catalyst for oils and fats, its preparation method, and its application. The hydrodeoxygenation composite support used in the hydrodeoxygenation catalyst provided by the present invention is hydrothermal resistant, which improves the hydrothermal stability of the catalyst during the hydrodeoxygenation process, thereby enhancing its deoxygenation effect.

[0016] To achieve the above objectives, on the one hand, the present invention provides a method for preparing a catalyst for the hydrodeoxygenation of oils and fats, wherein the preparation method includes:

[0017] Step 1: Mix aluminum-containing inorganic porous material, acidic solution, extrusion aid, magnesium salt and nickel salt and then extrude to obtain a carrier precursor. Dry and calcine the carrier precursor to obtain a hydrogenated deoxygenated composite carrier.

[0018] Step 2: Prepare an impregnation solution containing an active metal and impregnate the hydrodeoxygenation composite support with the impregnation solution containing the active metal, and then dry and calcine to obtain the oil hydrodeoxygenation catalyst.

[0019] As a specific embodiment of the preparation method described above in this invention, step 1, the preparation method of the hydrogenation-deoxygenation composite support specifically includes:

[0020] Step 11: Mix the aluminum-containing inorganic porous material with the extrusion aid to obtain a uniform powder;

[0021] Step 12: Dissolve the magnesium salt and nickel salt in an acidic solution to form a mixed solution;

[0022] Step 13: Mix the mixed solution and the uniform powder evenly to form a wet mixture;

[0023] Step 14: Extrude the wet mixture into strips to form a carrier precursor;

[0024] Step 15: Dry and calcine the carrier precursor to obtain the hydrogenated deoxygenated composite carrier.

[0025] As a specific embodiment of the preparation method described above in this invention, step 12 specifically includes: dissolving the magnesium salt in an acidic solution to form a first mixed solution, and then adding the nickel salt and the acidic solution to the first mixed solution to obtain a second mixed solution; or dissolving the magnesium salt and nickel salt separately in an acidic solution to form a first mixed solution and a second mixed solution, and then mixing the first mixed solution and the second mixed solution to obtain a third mixed solution; or dissolving the magnesium salt and nickel salt simultaneously in an acidic solution to form a mixed solution. Alternatively, when the magnesium salt is dissolved in water, step 12 can also involve first dissolving the magnesium salt in water to form a first mixed solution, and then adding the nickel salt and the acidic solution to the first mixed solution to obtain a second mixed solution.

[0026] As a specific embodiment of the preparation method described above in this invention, step 13 specifically includes: adding the mixed solution obtained in step 12 dropwise to the uniform powder obtained in step 11, and continuously stirring and mixing during the dropwise addition process to form a wet mixture.

[0027] As a specific embodiment of the preparation method described above in this invention, the content of magnesium and nickel is 0.5-10% and 0.3-2% respectively, based on the total weight of the hydrogenated deoxygenated composite carrier as 100%.

[0028] As a specific embodiment of the preparation method described above in this invention, the specific surface area of ​​the aluminum-containing inorganic porous material is not less than 180 m². 2 / g, preferably not less than 200m 2 / g, with a pore volume of not less than 0.3mL / g, preferably not less than 0.4mL / g.

[0029] As a specific embodiment of the preparation method described above in this invention, the aluminum-containing inorganic porous material includes any one of alumina and amorphous aluminum silica, or a combination of one or more inorganic porous materials such as zeolite molecular sieve, amorphous aluminum silica, silicon dioxide and zirconium dioxide with alumina.

[0030] In one specific embodiment of the preparation method described above, the amorphous aluminum silicate has the following composition (wherein silicon is calculated as silicon dioxide and aluminum as aluminum oxide): the mass ratio of aluminum oxide to silicon dioxide is 1:99-99:1, preferably 1:50-50:1. When the amorphous aluminum silicate is used alone as an aluminum-containing inorganic porous material, the mass ratio of aluminum oxide to silicon dioxide in the amorphous aluminum silicate is 10:1-50:1.

[0031] In one specific embodiment of the preparation method described above in this invention, the alumina includes one or a combination of macroporous alumina and microporous alumina. Furthermore, when the aluminum-containing inorganic porous material is a combination of one or more inorganic porous materials such as zeolite molecular sieves, amorphous aluminum silica, silica, and zirconium dioxide with alumina, this invention does not impose specific requirements on the ratio of alumina to other inorganic porous materials, and can be reasonably adjusted as needed.

[0032] As a specific embodiment of the preparation method described above in this invention, the magnesium salt includes one or a combination of several of magnesium nitrate hexahydrate, magnesium sulfate, magnesium carbonate, and magnesium chloride, preferably magnesium nitrate hexahydrate and / or magnesium carbonate, and / or the nickel salt includes one or a combination of several of nickel nitrate hexahydrate, nickel chloride, nickel sulfate, nickel bromide, nickel acetate, and basic nickel carbonate, preferably nickel nitrate hexahydrate and / or nickel acetate.

[0033] In one specific embodiment of the preparation method described above in this invention, the acidic solution includes one or a combination of several of the following: malic acid aqueous solution, acetic acid aqueous solution, nitric acid aqueous solution, hydrochloric acid aqueous solution, and sulfuric acid aqueous solution. The acidic solution used in this invention can dissolve both magnesium and nickel salts and also act as a binder. This invention does not impose specific requirements on the concentration of the above acidic solution and can adjust it reasonably as needed.

[0034] As a specific embodiment of the preparation method described above in this invention, the extrusion aid includes one or more of guar gum powder and polyhydroxy compounds.

[0035] As a specific embodiment of the preparation method described above in this invention, the polyhydroxy compound includes one or a combination of several of ethylene glycol, glycerol, cellulose, glucose, sucrose, fructose, and starch.

[0036] In one specific embodiment of the preparation method described above in this invention, in step 1, the drying temperature is 80-150℃, and / or the calcination temperature is 600-900℃. In step 1 of the preparation method described above, calcination is performed at 600-900℃. Calcination at this temperature can synthesize a nickel-doped hydrodeoxygenated composite support containing a magnesium-aluminum spinel structure. When the calcination temperature is below 600℃, this nickel-doped hydrodeoxygenated composite support cannot be synthesized. When the calcination temperature is above 900℃, the alumina in the aluminum-containing inorganic porous material will transform into low-activity or inert alumina (such as α-alumina), which will significantly reduce the activity of the catalyst supported on the active metal.

[0037] As a specific embodiment of the preparation method described above in this invention, step 2, the preparation method of the oil hydrodeoxygenation catalyst specifically includes:

[0038] Step 21: Prepare an impregnation solution containing active metals and complexing agents;

[0039] Step 22: Impregnate the hydrodeoxygenated composite carrier with an impregnation solution containing an active metal and a complexing agent;

[0040] Step 23: The product obtained in step 22 is subjected to conditioning, drying and calcination to obtain the oil hydrodeoxygenation catalyst.

[0041] In one specific embodiment of the preparation method described above in this invention, the health preservation in step 23 is constant temperature health preservation. This invention does not impose specific requirements on the temperature of the constant temperature health preservation, which can be reasonably adjusted as needed.

[0042] In one specific embodiment of the preparation method described above in this invention, the active metal includes at least two of group VIB and VIII metals, preferably at least two of Co, Mo, Ni, and W. This invention does not impose specific requirements on the precursor of the active metal used in preparing the oil hydrodeoxygenation catalyst; it can be selected reasonably as needed. For example, in some embodiments of this invention, the precursor of the active metal can be a salt of the active metal. Furthermore, when the active metal is molybdenum and the precursor is ammonium molybdate, a weak alkali needs to be added when preparing the impregnation solution in step 21 to dissolve the ammonium molybdate in a weakly alkaline environment. This invention does not impose specific requirements on the specific substance of the weak alkali; it can be selected reasonably as needed. For example, in some embodiments of this invention, the weak alkali can be ammonia water of a certain concentration.

[0043] As a specific embodiment of the preparation method described above in this invention, the complexing agent includes organic compounds containing multiple hydroxyl groups, etc.

[0044] As a specific embodiment of the preparation method described above in this invention, the organic compound containing multiple hydroxyl groups refers to an organic compound containing two or more hydroxyl groups, including one or a combination of several of citric acid, malic acid, oxalic acid, ethylenediaminetetraacetic acid, ethylene glycol, and glycerol.

[0045] As a specific embodiment of the preparation method described above in this invention, the impregnation is performed at 10-30°C for 1-4 hours.

[0046] As a specific embodiment of the preparation method described above in this invention, in step 2, the drying temperature is 150-300℃, and / or the calcination temperature is 300-500℃.

[0047] On the other hand, the present invention also provides a hydrodeoxygenation catalyst for oils and fats, which is prepared by the above-described method for preparing hydrodeoxygenation catalyst for oils and fats, comprising a hydrodeoxygenation composite support and an active metal supported on the hydrodeoxygenation composite support, wherein the active metal content is 15-35% and the balance is the hydrodeoxygenation composite support, based on the total weight of the hydrodeoxygenation catalyst for oils and fats being 100%.

[0048] As a specific embodiment of the above-described oil hydrodeoxygenation catalyst of the present invention, the content of magnesium is 0.2-7% and the content of nickel is 0.2-5% based on the total weight of the oil hydrodeoxygenation catalyst as 100%.

[0049] In another aspect, the present invention also provides the application of the above-described oil hydrodeoxygenation catalyst in the preparation of jet fuel by oil hydrodeoxygenation.

[0050] Compared with the prior art, the beneficial technical effects achieved by the present invention include:

[0051] This invention utilizes a combination of magnesium and nickel salts in the preparation of the hydrodeoxygenation composite support, resulting in a hydrodeoxygenation composite support with a nickel-doped magnesium-aluminum spinel structure. This hydrodeoxygenation composite support with a nickel-doped magnesium-aluminum spinel structure exhibits good hydrothermal stability and mechanical strength; after hydrothermal treatment, the specific surface area of ​​the support decreases only slightly, maintaining high mechanical strength. The oil hydrodeoxygenation catalyst prepared by loading the active metal component onto this hydrodeoxygenation composite support demonstrates stable deoxygenation activity and excellent deoxygenation effect. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0053] Figure 1 is the XRD pattern of carrier A provided in Embodiment 1 of the present invention.

[0054] Figure 2 shows the XRD pattern of the carrier H provided in Comparative Example 1.

[0055] Figure 3 shows the XRD pattern of carrier I provided in Comparative Example 2.

[0056] Figure 4 shows the XRD pattern of carrier J provided in Comparative Example 3. Detailed Implementation

[0057] It should be noted that the term "comprising" and any variations thereof in the specification, claims, and accompanying drawings of this invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or devices.

[0058] The "range" disclosed in this invention is given in the form of a lower limit and an upper limit. It can be one or more lower limits and one or more upper limits, respectively. A given range is defined by selecting a lower limit and an upper limit. The selected lower and upper limits define the boundaries of the particular range. All ranges defined in this way are composable, meaning that any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for specific parameters, it is also expected that ranges of 60-110 and 80-120 are also expected. Furthermore, if the listed minimum range values ​​are 1 and 2, and the listed maximum range values ​​are 3, 4, and 5, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5.

[0059] In this invention, unless otherwise specified, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this invention, and "0-5" is simply a shortened representation of these numerical combinations.

[0060] In this invention, unless otherwise specified, all embodiments and preferred embodiments mentioned in this invention can be combined with each other to form new technical solutions.

[0061] In this invention, unless otherwise specified, all technical features and preferred features mentioned in this invention can be combined with each other to form new technical solutions.

[0062] In this invention, unless otherwise specified, all steps mentioned herein may be performed sequentially or randomly, but are preferably performed sequentially. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, if the method may also include step (c), it means that step (c) may be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0063] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying tables, drawings, and embodiments. The embodiments described below are some, but not all, embodiments of this invention, and are only used to illustrate the invention, and should not be considered as limiting the scope of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0064] The specific surface area and pore volume data of the inorganic porous materials used in the embodiments of the present invention are shown in Table 1 below. The specific surface area and pore volume of the inorganic porous materials in Table 1 are only for the purposes of this invention and are not limited to the properties of the materials in Table 1.

[0065] Table 1

[0066] In Table 1, the composition of amorphous silicon-aluminum is as follows (where silicon is calculated as silicon dioxide and aluminum as aluminum oxide): the mass ratio of aluminum oxide to silicon dioxide is 40:1.

[0067] Example 1

[0068] This embodiment provides a method for preparing a catalyst for the hydrodeoxygenation of oils and fats, wherein the preparation method includes the following steps:

[0069] Step 1: Preparation of the carrier.

[0070] Step 11: Take 13.5g of macroporous alumina and 68.1g of microporous alumina and mix them with 3.5g of starch to form a uniform powder;

[0071] Step 12: Weigh 32g of MgCO3, take a 10mol / L H2SO4 aqueous solution and use it to completely dissolve the MgCO3 to form the first mixed solution;

[0072] Step 13: Take 7g of 30wt% HCl aqueous solution and 9.23g of nickel nitrate hexahydrate, add them to the first mixed solution and dissolve them completely, then dilute to 81mL with deionized water to form the second mixed solution;

[0073] Step 14: Add the second mixed solution dropwise to the uniform powder, stirring continuously during the dropwise addition process to mix the system evenly and form a wet mixture;

[0074] Step 15: Extrude the wet mixture into strips on an extruder to form the carrier precursor;

[0075] Step 16: The precursor was dried at 120℃ for 2 hours, and then calcined in a muffle furnace at 800℃ for 6 hours in air atmosphere to obtain a hydrodeoxygenated composite support, denoted as support A. The XRD pattern of support A is shown in Figure 1. As can be seen from Figure 1, support A is a composite support containing magnesium aluminum spinel, and the diffraction peak intensity of magnesium aluminum spinel in support A is relatively strong. This indicates that the magnesium aluminum spinel formed by adding nickel salt during the preparation of the hydrodeoxygenated composite support in this embodiment has stronger diffraction peaks and better crystallization.

[0076] Step 2: Loading of active metals.

[0077] Step 21: Weigh 50g of carrier A and set aside for later use;

[0078] Step 22: Weigh 1.5g of ethylenediaminetetraacetic acid, 21.55g of ammonium metatungstate and 8.46g of nickel nitrate hexahydrate and dissolve them in deionized water, then make up to 45mL to form an impregnation solution.

[0079] Step 23: Immerse 50g of carrier A in the impregnation solution at a temperature of 25°C and continue immersion for 1 hour;

[0080] Step 24: The product obtained in Step 23 is subjected to constant temperature conditioning at 20℃ for 2 hours, drying at 200℃ for 10 hours, and calcination at 300℃ for 6 hours to obtain the oil hydrodeoxygenation catalyst, denoted as CAT-A. The total content of tungsten and nickel is 24.5% based on the total weight of CAT-A as 100%.

[0081] Example 2

[0082] This embodiment provides a method for preparing a catalyst for the hydrodeoxygenation of oils and fats, wherein the preparation method includes the following steps:

[0083] Step 1: Preparation of the carrier.

[0084] Step 11: Take 70g of macroporous alumina, 10g of microporous alumina, and 11.7g of amorphous aluminosilicate and mix them evenly with 4g of guar gum powder to form a uniform powder;

[0085] Step 12: Weigh 49.07g of Mg(NO3)2·6H2O and dissolve it in 50mL of deionized water to obtain the first mixed solution;

[0086] Step 13: Take 3.5g of 65wt% HNO3 and 2.14g of nickel chloride, add them to the first mixed solution and dissolve them completely, then add deionized water to make up to 83mL to obtain the second mixed solution;

[0087] Step 14: Add the second mixed solution dropwise to the uniform powder, stirring continuously during the dropwise addition process to mix the system evenly and form a wet mixture;

[0088] Step 15: Extrude the wet mixture into strips on an extruder to form the carrier precursor;

[0089] Step 16: Dry the carrier precursor at 80℃ for 6 hours, and then calcine it in a muffle furnace at 700℃ for 6 hours under air atmosphere to obtain the hydrogenated deoxygenated composite carrier, denoted as carrier B.

[0090] Step 2: Loading of active metals.

[0091] Step 21: Weigh 50g of carrier B and set aside for later use;

[0092] Step 22: Weigh 30 mL of 5 wt% ammonia water, 16.59 g of ammonium molybdate, 14.44 g of cobalt nitrate hexahydrate, 14.80 g of nickel nitrate hexahydrate and 1.0 g of glycerol and dissolve them in deionized water, then make up to 45 mL to form an impregnation solution.

[0093] Step 23: Immerse 50g of carrier B in the impregnation solution at a temperature of 10°C for 2 hours.

[0094] Step 24: The product obtained in Step 23 is subjected to constant temperature conditioning at 25°C for 3 hours, drying at 150°C for 4 hours, and calcination at 500°C for 2 hours to obtain the oil hydrodeoxygenation catalyst, denoted as CAT-B. The total content of cobalt, molybdenum, and nickel is 20.4% based on the total weight of CAT-B as 100%.

[0095] Example 3

[0096] This embodiment provides a method for preparing a hydrodeoxygenation catalyst for oils, including the preparation of a support and the loading of an active metal. The difference between step 1, the preparation of the support, and step 2 in this embodiment lies only in the following:

[0097] In step 11, guar gum powder was replaced with cellulose; in step 12, 49.07 g of Mg(NO3)2·6H2O was replaced with 19.80 g of MgCl2; in step 13, 3.5 g of 65 wt% HNO3 and 2.14 g of nickel chloride were replaced with 10 g of 5 mol / L acetic acid aqueous solution and 2.91 g of nickel acetate; and the carrier precursor in step 16 was dried at 100 °C for 4 h and calcined at 750 °C for 6 h to obtain carrier C.

[0098] Step 2: Loading of active metals, including:

[0099] Step 21: Weigh 50g of carrier C and set aside for later use;

[0100] Step 22: Weigh 30 mL of 5 wt% ammonia water, 18.01 g of ammonium molybdate, 6.86 g of nickel nitrate hexahydrate and 1.3 g of citric acid and dissolve them in deionized water, then make up to 45 mL to form an impregnation solution.

[0101] Step 23: Immerse 50g of carrier C in the impregnation solution at a temperature of 30°C for 4 hours.

[0102] Step 24: The product obtained in Step 23 is subjected to constant temperature conditioning at 30℃ for 1 hour, drying at 230℃ for 5 hours, and calcination at 400℃ for 5 hours to obtain the oil hydrodeoxygenation catalyst, denoted as CAT-C. The total content of molybdenum and nickel is 16.4% based on the total weight of CAT-C as 100%.

[0103] Example 4

[0104] This embodiment provides a method for preparing a hydrodeoxygenation catalyst for oils, including the preparation of a support and the loading of an active metal. The difference between step 1, the preparation of the support, and step 2 in this embodiment lies only in the following:

[0105] In step 11, the guar gum powder was replaced with glycerol; in step 12, the 49.07g of Mg(NO3)2·6H2O was replaced with 25.0g of MgSO4; in step 13, the 3.5g of 65wt% HNO3 and 2.14g of nickel chloride were replaced with 6g of 3mol / L sulfuric acid and 2.06g of basic nickel carbonate; and the carrier precursor in step 16 was dried at 150℃ for 2h and calcined at 800℃ for 6h to obtain carrier D.

[0106] Step 2: Loading of active metals, including:

[0107] Step 21: Weigh 50g of carrier D and set aside for later use;

[0108] Step 22: Weigh 0.5g of ethylene glycol, 16.23g of ammonium metatungstate and 16.21g of nickel nitrate hexahydrate and dissolve them in deionized water, then make up to 45mL to form an impregnation solution.

[0109] Step 23: At a temperature of 25°C, the impregnation solution is impregnated onto 50g of carrier D and the impregnation is continued for 2 hours;

[0110] Step 24: The product obtained in Step 23 is subjected to constant temperature conditioning, drying at 280℃ for 6 hours and calcination at 450℃ for 3 hours to obtain the oil hydrodeoxygenation catalyst, denoted as CAT-D. The total content of tungsten and nickel is 23.1% based on the total weight of CAT-D as 100%.

[0111] Example 5

[0112] This embodiment provides a method for preparing a hydrodeoxygenation catalyst for oils, including the preparation of a support and the loading of an active metal. The difference between step 1, the preparation of the support, and step 2 in this embodiment lies only in the following:

[0113] In step 11, the guar gum powder was replaced with glucose, and in step 13, the 3.5g of 65wt% HNO3 was replaced with 7.3g of 6mol / L malic acid aqueous solution. The carrier precursor in step 16 was dried at 120℃ for 3h and calcined at 900℃ for 4h to obtain carrier E.

[0114] Step 2: The only difference between the loading of the active metal and Example 1 is that:

[0115] Replace 1.5g of ethylenediaminetetraacetic acid in step 22 with 2.0g of malic acid and dry at 240℃ for 8h in step 24 to obtain CAT-E. The total content of tungsten and nickel is 24.5% based on the total weight of CAT-E as 100%.

[0116] Example 6

[0117] This embodiment provides a method for preparing a catalyst for the hydrodeoxygenation of oils and fats, wherein the preparation method includes the following steps:

[0118] Step 1: Preparation of the carrier.

[0119] Step 11: Take 60g of macroporous alumina, 23g of microporous alumina, 15g of amorphous silica-alumina, 1.2g of zirconium dioxide and 4.6g of guar gum powder and mix them evenly to form a uniform powder.

[0120] Step 12: Weigh 5.38g of Mg(NO3)2·6H2O and dissolve it in 50mL of deionized water to obtain the first mixed solution;

[0121] Step 13: Take 4.6g of 65wt% HNO3 and 2.3g of nickel bromide, add them to the first solution and dissolve them completely, then add deionized water and make up to 91mL to form the second mixed solution;

[0122] Step 14: Add the second mixed solution dropwise to the uniform powder, stirring continuously during the dropwise addition process to mix the system evenly and form a wet mixture;

[0123] Step 15: Extrude the wet mixture into strips on an extruder to form the carrier precursor;

[0124] Step 16: Dry the carrier precursor at 120℃ for 4 hours, and then calcine it in a muffle furnace at 800℃ for 6 hours in an air atmosphere to obtain a hydrogenated deoxygenated composite carrier, denoted as carrier F.

[0125] Step 2: The only difference between the loading of the active metal and Example 1 is that:

[0126] Replace 1.5g of ethylenediaminetetraacetic acid in step 22 with 3.0g of oxalic acid and dry at 260℃ for 8h in step 24 to obtain CAT-F. The total content of tungsten and nickel is 24.5% based on the total weight of CAT-F as 100%.

[0127] Example 7

[0128] This embodiment provides a method for preparing a catalyst for the hydrodeoxygenation of oils and fats, wherein the preparation method includes the following steps:

[0129] Step 1: Preparation of the carrier.

[0130] Step 11: Take 58.5g of macroporous alumina, 37g of microporous alumina and 4.2g of ethylene glycol and mix them evenly to form a uniform powder;

[0131] Step 12: Weigh 32g of Mg(NO3)2·6H2O and dissolve it in 50mL of deionized water to obtain the first mixed solution;

[0132] Step 13: Take 4.6g of 65wt% HNO3 and 4.52g of nickel acetate, add them to the first solution and dissolve them completely, then add deionized water and make up to 89mL to form the second mixed solution;

[0133] Step 14: Add the second mixed solution dropwise to the uniform powder, stirring continuously during the dropwise addition process to mix the system evenly and form a wet mixture;

[0134] Step 15: Extrude the wet mixture into strips on an extruder to form the carrier precursor;

[0135] Step 16: Dry the carrier precursor at 120℃ for 4 hours, and then calcine it in a muffle furnace at 600℃ for 6 hours in an air atmosphere to obtain a hydrogenated deoxygenated composite carrier, denoted as carrier G. The total weight of carrier G is 100%, and the contents of magnesium and nickel are 3.0% and 1.5%, respectively.

[0136] Step 2: The only difference between the loading of the active metal and Example 1 is that:

[0137] Step 22 involves weighing 1.0 g of ethylenediaminetetraacetic acid, 0.5 g of citric acid, 25.97 g of ammonium metatungstate, and 20.3 g of nickel nitrate hexahydrate, dissolving them in deionized water, and bringing the volume to 45 mL to form an impregnation solution. This solution is then dried at 230 °C for 8 hours as described in step 24 to obtain CAT-G. Based on the total weight of CAT-G (100%), the total content of tungsten and nickel is 34.9%.

[0138] Comparative Example 1

[0139] This comparative example provides a method for preparing a catalyst for the hydrodeoxygenation of oils and fats, including the preparation of a support and the loading of an active metal. The difference between the support preparation method and that of Example 1 is that nickel nitrate hexahydrate is not added, resulting in support H, whose XRD pattern is shown in Figure 2. Figure 2 shows that support H also possesses a magnesium aluminum spinel structure, but the diffraction peak intensity of the magnesium aluminum spinel formed is weaker than that of support A provided in Example 1. This indicates that although Comparative Example 1 also obtained a composite support containing magnesium aluminum spinel, the crystallinity of the magnesium aluminum spinel is not high, lower than that of support A. Comparing Figures 1 and 2, it can be seen that the nickel salt added in this embodiment of the invention is beneficial for forming a magnesium aluminum spinel structure with stronger diffraction peaks and better crystallinity.

[0140] The loading of the active metal was the same as in Example 1, and the resulting catalyst was CAT-H.

[0141] Comparative Example 2

[0142] This comparative example provides a method for preparing a hydrodeoxygenation catalyst for oils, including the preparation of a support and the loading of an active metal. The difference between the support preparation method and that in Example 1 is that nickel nitrate hexahydrate is not added, and the support is calcined at 500°C for 6 hours to obtain support I. Its XRD pattern is shown in Figure 3. As can be seen from Figure 3, no magnesium aluminum spinel structure is formed in support I. This indicates that the calcination temperature during the support preparation process is too low to reach the crystallization temperature required for magnesium aluminum spinel formation. Magnesium and aluminum elements exist in the support in their respective individual elemental forms. Specifically, aluminum exists in the form of alumina in the obtained support, while magnesium is dispersed in the obtained support in an amorphous form.

[0143] The loading of the active metal was the same as in Example 1, and the resulting catalyst was CAT-I.

[0144] Comparative Example 3

[0145] This comparative example provides a method for preparing a hydrodeoxygenation catalyst for oils, including the preparation of a support and the loading of an active metal. The difference between this method and Example 1 lies in the preparation of the support: nickel nitrate hexahydrate is not added, and the calcination temperature is 550℃ for 6 hours, yielding support J. Its XRD pattern is shown in Figure 4. Figure 4 shows that no magnesium aluminum spinel structure was formed in support J. This indicates that the calcination temperature during support preparation was too low to reach the crystallization temperature required for magnesium aluminum spinel formation. Magnesium and aluminum elements exist in the support in their respective individual elemental forms. Specifically, aluminum exists in the form of alumina in the obtained support, while magnesium is dispersed in the obtained support in an amorphous form.

[0146] The difference between the active metal loading and Example 2 is only that: glycerol is not used in step 22 and the drying in step 24 is 150°C for 4 hours and calcination is 550°C for 6 hours, CAT-J.

[0147] Comparative Example 4

[0148] This comparative example provides a method for preparing a catalyst for the hydrodeoxygenation of oils and fats, wherein the preparation method includes the following steps:

[0149] Step 1: Preparation of the carrier.

[0150] Step 11: Take 60g of macroporous alumina, 22.25g of microporous alumina, 17.75g of magnesium aluminum spinel (MgAl2O4) and 4.2g of guar gum powder and mix them evenly to form a uniform powder;

[0151] Step 12: Take 4.6g of 65% HNO3 and add it to deionized water, then make up to 90mL to obtain a mixed solution;

[0152] Step 13: Add the mixed solution dropwise to the uniform powder, stirring continuously during the dropwise addition process to mix the system evenly and form a wet mixture;

[0153] Step 15: Extrude the wet mixture into strips on an extruder to form the carrier precursor;

[0154] Step 16: Dry the carrier precursor at 120℃ for 4 hours, and then calcine it in a muffle furnace at 600℃ for 6 hours in an air atmosphere to obtain the hydrogenated deoxygenated composite carrier, denoted as carrier K.

[0155] Step 2: Loading of active metals, which differs from Comparative Example 1 only in that the calcination temperature is 450℃ and the calcination time is 6h, to obtain CAT-K.

[0156] Test Example 1

[0157] In this test example, X-ray fluorescence characterization (XRF) was performed on supports A to K to analyze the mass fraction of magnesium and nickel in the respective supports. The experimental results are shown in Table 2.

[0158] Table 2

[0159] As can be seen from Table 2 above, compared with the carriers H and K in Comparative Examples 1-4, the combination of magnesium salt and nickel salt in the preparation of the hydrodeoxygenation composite carrier AG in Examples 1-7 of the present invention can successfully dope nickel into the hydrodeoxygenation composite carrier.

[0160] Test Example 2

[0161] This test case examines the specific surface area and lateral pressure strength of the hydrogenated deoxygenated composite carriers before and after hydrothermal treatment. The test included: taking 15g of carriers A to K respectively and subjecting each carrier A to K to hydrothermal treatment. The hydrothermal treatment pressure was 0.6MPa, and the treatment was carried out at 600℃ and saturated water vapor for 10h. Then, the specific surface area and lateral pressure strength of carriers A to K and carriers A to K after hydrothermal treatment were measured using conventional techniques in this field. The experimental data are shown in Table 3 below.

[0162] Table 3

[0163] As shown in Table 3, the supports I and J prepared in Comparative Examples 2 and 3 have higher specific surface areas. This is partly due to the lower calcination temperature used, resulting in less pore structure condensation and thus a larger specific surface area. Another reason is that nickel salts were not used during the preparation of the supports, which also appropriately increases the specific surface area of ​​the resulting supports. However, the specific surface area and lateral compressive strength of the supports decreased significantly after hydrothermal treatment. The support K prepared in Comparative Example 4 has a high specific surface area, but its compressive strength is poor. After hydrothermal treatment, the specific surface area also decreased significantly. The support H prepared in Comparative Example 1 also experienced a decrease in specific surface area and lateral compressive strength after hydrothermal treatment, but the decrease was less than that of the support I prepared in Comparative Example 2.

[0164] The supports A-G prepared in Examples 1-7 of this invention also exhibit high specific surface area and lateral pressure strength. Compared to supports H-K prepared in Comparative Examples 1-4, supports A-G show a smaller decrease in specific surface area and lateral pressure strength after hydrothermal treatment. For the hydrodeoxygenation supports prepared in the comparative examples, the decrease in specific surface area and lateral pressure strength before and after hydrothermal treatment is significant, failing to meet the requirements for hydrodeoxygenation supports. The supports prepared in the embodiments of this invention are potentially suitable hydrodeoxygenation supports. This indicates that when preparing the hydrodeoxygenated composite support in the embodiments of the present invention, the combined use of magnesium salt and nickel salt can yield a hydrodeoxygenated composite support with a nickel-doped magnesium-aluminum spinel structure. That is, the addition of nickel salt is beneficial to promoting the formation of a more stable magnesium-aluminum spinel structure. In contrast, no nickel salt was added when preparing support H in Comparative Example 1. Although a magnesium-aluminum spinel structure can be formed in support H, the crystallinity of this magnesium-aluminum spinel structure is not high, and its hydrothermal resistance is poor. In Comparative Example 2, although nickel salt was added when preparing support I, the calcination temperature was only 500°C. No magnesium-aluminum spinel structure was formed in the resulting support I. The aluminum element mainly exists in the form of alumina, and the magnesium element is distributed in an amorphous form in the alumina support. At this time, the properties of the support are mainly determined by the alumina. However, the alumina support has poor hydrothermal resistance during hydrothermal treatment, so the hydrothermal resistance of support I is also poor.

[0165] Therefore, the hydrodeoxygenation composite supports with nickel-doped magnesium-aluminum spinel structures provided in Examples 1-7 of this invention have good hydrothermal stability and mechanical strength. After hydrothermal treatment, the specific surface area of ​​the support decreases less and can maintain high mechanical strength. In particular, during the hydrodeoxygenation process, the more stable magnesium-aluminum spinel structure in the composite support makes the composite support have excellent hydrothermal stability, thereby making the catalyst prepared from the composite support more stable in activity.

[0166] Test Example 3

[0167] This test example uses a fixed-bed reactor to evaluate the hydrodeoxygenation performance of catalysts CAT-A, CAT-B, CAT-H, CAT-I, and CAT-J, including:

[0168] 20 mL of each of CAT-A, CAT-B, CAT-H, CAT-I, and CAT-J was taken and loaded into a fixed-bed reactor. The catalysts were subjected to sulfidation treatment, and the deoxygenation performance was evaluated using fatty acid methyl esters with impurities removed as feedstock. The properties of the feedstock are shown in Table 4, the evaluation process conditions are shown in Table 5, and the evaluation results of the hydrodeoxygenation performance are shown in Table 6.

[0169] Table 4

[0170] Table 5

[0171] Table 6

[0172] As can be seen from Table 6 above, the hydrodeoxygenation catalysts CAT-H to CAT-J prepared by loading metal active components onto the supports provided in Comparative Examples 1-3 showed a significant decrease in deoxygenation activity after 1000 hours of operation compared to after 20 hours. In contrast, the hydrodeoxygenation catalysts CAT-A and CAT-B prepared by loading metal active components onto the supports provided in Examples 1 and 2 of this invention showed that their catalytic activity (mainly reflected in the oxygen content of the product and the yield of the liquid product) remained essentially unchanged after 1000 hours of operation compared to their initial activity (after 20 hours). This is attributed to the more stable magnesium-aluminum spinel structure in the composite support provided in the embodiments of this invention. This more stable magnesium-aluminum spinel structure gives the composite support excellent hydrothermal stability, thereby making the activity of the catalyst prepared using the composite support more stable.

[0173] In summary, the present invention utilizes a combination of magnesium and nickel salts in the preparation of the hydrodeoxygenation composite support, resulting in a hydrodeoxygenation composite support with a nickel-doped magnesium-aluminum spinel structure. This hydrodeoxygenation composite support with a nickel-doped magnesium-aluminum spinel structure exhibits good hydrothermal stability and mechanical strength; after hydrothermal treatment, the specific surface area of ​​the support decreases only slightly, maintaining high mechanical strength. The oil hydrodeoxygenation catalyst prepared by loading the active metal component onto this hydrodeoxygenation composite support demonstrates stable deoxygenation activity and excellent deoxygenation effect.

[0174] The above description is merely a specific embodiment of the present invention and should not be construed as limiting the scope of the invention. Therefore, any substitution of equivalent components or equivalent changes and modifications made within the scope of protection of this patent should still fall within the scope of this patent. Furthermore, the technical features, technical features and technical inventions, and technical inventions in this invention can be freely combined and used.

Claims

1. A method for preparing a catalyst for the hydrodeoxygenation of oils and fats, characterized in that, The preparation method includes: Step 1: Mix aluminum-containing inorganic porous material, acidic solution, extrusion aid, magnesium salt and nickel salt, and then extrude to obtain a carrier precursor. Dry and calcine the carrier precursor to obtain a hydrodeoxygenation composite carrier. Step 2: Prepare an impregnation solution containing active metal and impregnate the hydrodeoxygenation composite carrier with the impregnation solution containing active metal. Then dry and calcine to obtain the oil hydrodeoxygenation catalyst.

2. The preparation method according to claim 1, characterized in that, In step 1, the preparation method of the hydrogenation-deoxygenation composite support specifically includes: Step 11: Mix the aluminum-containing inorganic porous material with the extrusion aid to obtain a uniform powder; Step 12: Dissolve the magnesium salt and nickel salt in an acidic solution to form a mixed solution; Step 13: Mix the mixed solution and the uniform powder evenly to form a wet mixture; Step 14: Extrude the wet mixture into strips to form a carrier precursor; Step 15: Dry and calcine the carrier precursor to obtain the hydrogenated deoxygenated composite carrier.

3. The preparation method according to claim 1 or 2, characterized in that, Based on the total weight of the hydrodeoxygenated composite carrier as 100%, the content of magnesium and nickel is 0.5-10% and 0.3-2%, respectively.

4. The preparation method according to claim 1 or 2, characterized in that, The specific surface area of ​​the aluminum-containing inorganic porous material is not less than 180 m². 2 / g, pore volume not less than 0.3mL / g.

5. The preparation method according to claim 4, characterized in that, The aluminum-containing inorganic porous material includes any one of alumina and amorphous aluminum silicate, or a combination of one or more inorganic porous materials selected from zeolite molecular sieves, amorphous aluminum silicate, silicon dioxide and zirconium dioxide with alumina.

6. The preparation method according to claim 1 or 2, characterized in that, The magnesium salt includes one or a combination of magnesium nitrate hexahydrate, magnesium sulfate, magnesium carbonate, and magnesium chloride, and / or the nickel salt includes one or a combination of nickel nitrate hexahydrate, nickel chloride, nickel sulfate, nickel bromide, nickel acetate, and basic nickel carbonate.

7. The preparation method according to claim 1 or 2, characterized in that, The acidic solution includes one or a combination of several of the following: malic acid aqueous solution, acetic acid aqueous solution, nitric acid aqueous solution, hydrochloric acid aqueous solution, and sulfuric acid aqueous solution; And / or the extrusion aid includes one or more of guar gum powder and polyhydroxy compounds.

8. The preparation method according to claim 1 or 2, characterized in that, In step 1, the drying temperature is 80-150℃, and / or the calcination temperature is 600-900℃.

9. The preparation method according to claim 1, characterized in that, Step 2, the preparation method of the oil hydrodeoxygenation catalyst specifically includes: Step 21: Prepare an impregnation solution containing active metals and complexing agents; Step 22: Impregnate the hydrodeoxygenated composite carrier with an impregnation solution containing an active metal and a complexing agent; Step 23: The product obtained in step 22 is subjected to conditioning, drying and calcination to obtain the oil hydrodeoxygenation catalyst.

10. The preparation method according to claim 1 or 9, characterized in that, The active metal includes at least two of the group VIB and VIII metals.

11. The preparation method according to claim 9, characterized in that, The complexing agent includes organic compounds containing multiple hydroxyl groups.

12. A hydrodeoxygenation catalyst for oils and fats, prepared by the method of any one of claims 1-11, comprising a hydrodeoxygenation composite support and an active metal supported on the hydrodeoxygenation composite support, wherein the active metal content is 15-35% and the balance is the hydrodeoxygenation composite support, based on the total weight of the hydrodeoxygenation catalyst for oils and fats being 100%.

13. The application of the oil hydrodeoxygenation catalyst according to claim 12 in the preparation of jet fuel by oil hydrodeoxygenation.

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