Zsm-48 molecular sieve and method for preparing same, isomerization dewaxing catalyst and method for preparing and using same

Abstract

The application provides a ZSM-48 molecular sieve and a preparation method thereof, an isomerization dewaxing catalyst and a preparation method and application thereof, wherein the preparation method of the ZSM-48 molecular sieve comprises the following steps: uniformly mixing an aluminum source, a silicon source, an alkali source, a crystallization inducer, a template agent, deionized water, a pore-forming agent and a charge balancing agent, then sequentially pre-crystallizing the obtained gel solution at 70-90 DEG C for 2-6h, crystallizing at 120-140 DEG C for 2-6h, and crystallizing at 140-170 DEG C for 10-48h, washing, drying and calcining the crystallization product, mixing the obtained molecular sieve precursor with an ammonium salt, and then washing, drying and calcining to obtain the ZSM-48 molecular sieve. The carrier particle of the isomerization dewaxing catalyst comprises the ZSM-48 molecular sieve. The acid sites of the molecular sieve are uniformly distributed, the crystal grain size is small, and the total BET specific surface area is high. The isomerization dewaxing catalyst has high reaction efficiency and isomerization conversion rate and low cracking rate.

Description

TECHNICAL FIELD

[0001] The present application relates to a ZSM-48 molecular sieve and a preparation method thereof, an isomerization dewaxing catalyst and a preparation method and application thereof, and belongs to the technical field of molecular sieve catalysts. BACKGROUND

[0002] The demand for II and III type base oils produced by isomerization dewaxing technology is increasing year by year, and lubricating oil base oil is one of the important products for refining characteristic products and profit creation in refineries. The isomerization dewaxing catalyst is mainly used in isomerization dewaxing, make-up refining and white oil hydrogenation catalyst preparation in lubricating oil hydrogenation isomerization technology. The key technology of isomerization dewaxing is the preparation of noble metal catalyst. For a bifunctional catalyst with high isomerization selectivity and low cracking activity, the active metal is generally a noble metal such as Pt and Pd, which plays a role of dehydrogenation and hydrogenation on alkanes or alkenes; the carrier is mainly a molecular sieve, which provides acidity and pore restriction and shape selection effect in the isomerization reaction process. Generally, aluminum phosphate, silicon-aluminum molecular sieves with one-dimensional straight pore structure are used, typical representatives are SAPO-11, ZSM-22, ZSM-23, ZSM-48 and ZSM-12, etc. The pore confinement effect and acidity characteristics determine the difference in the conversion ability of different raw materials and the structure of the products.

[0003] Some existing technologies related to the present application will be briefly introduced below:

[0004] CN 112934258 A discloses a composite molecular sieve, a preparation method thereof, a hydrogenation isomerization catalyst and a method for hydrogenation isomerization of Fischer-Tropsch synthetic oil. The composite molecular sieve has a core-shell structure, the core-shell structure includes an inner core and an outer shell covering the inner core, the inner core contains a modified ZSM-48 molecular sieve, and the outer shell contains an MCM-41 molecular sieve. The content of the outer shell is 0.1-50 wt%, and the content of the inner core is 50-99.9 wt% based on the total weight of the composite molecular sieve. The hydrogenation isomerization catalyst prepared from the composite molecular sieve is used for Fischer-Tropsch synthetic oil hydrogenation isomerization reaction, has better isomerization selectivity, and can produce high-quality and high-yield lubricating oil base oil. However, the defects or disadvantages of the technology relative to the present application include: the preparation process of the composite molecular sieve catalyst is more complex, the thickness and uniformity of the MCM-41 molecular sieve coating outside the ZSM-48 molecular sieve cluster are difficult to accurately control, and the pore dispersion and acidity control are difficult.

[0005] CN 105214718 A discloses a preparation method of isomerization dewaxing catalyst, which adds a certain amount of alkali earth metal soluble salt solution to the carrier during the shaping of the catalyst carrier to modify the carrier; and a solvent-thermal-ion exchange method is used in the step of loading active metal components, in which the solvent-thermal-ion exchange method is to replace water with solvent, and the active components are loaded onto the catalyst carrier by ion exchange under certain temperature and pressure conditions. The prior art also provides the isomerization dewaxing catalyst prepared by the above method, which is used for isomerization dewaxing of lubricating oil fraction to produce low pour point and high viscosity index lubricating oil base oil, and has the characteristics of moderate catalyst acidity, high metal dispersion, high isomerization dewaxing reactivity and selectivity, low lubricating oil base oil pour point and high yield. However, the defects of the technology or the deficiencies of the technology relative to the present application include that the active components are loaded onto the catalyst carrier by solvent-thermal-ion exchange under certain temperature and pressure conditions, and volatile small molecule alcohols are used as solvents, which increases the cost and makes the process difficult to control.

[0006] CN 105709817 A discloses an isomerization dewaxing catalyst and a preparation method thereof, which is to embed small crystal MTT type molecular sieves loaded with hydrogenation active components in organic starch or polyvinyl alcohol, then mix the organic starch or polyvinyl alcohol with a precursor of high-temperature-resistant inert oxide uniformly, shape, dry and calcine to obtain the isomerization dewaxing catalyst. The catalyst provided by the prior art is suitable for isomerization dewaxing process of lubricating oil fraction. Since the amount of molecular sieves in the catalyst is greatly reduced, not only the production cost of the catalyst is greatly reduced, but also the discharge of difficult-to-treat wastewater in the synthesis process of the molecular sieves is avoided, and the catalyst has the characteristics of high yield of target product and low pour point. However, the defects of the technology or the deficiencies of the technology relative to the present application include that the MTT type molecular sieves are embedded in the organic starch or polyvinyl alcohol, and the coking of the organic matter during calcination produces carbon deposition, causing the blockage of the molecular sieve channels, and in addition, the selected organic matter has a large molecular weight, which is not conducive to the dispersion of the metal.

[0007] CN 105800635 A discloses a preparation method of ZSM-48 molecular sieves with mesopore-micropore hierarchical structure, which is to homogenize and mix an aluminum source, sodium hydroxide and deionized water, add a template agent and a silicon source, homogenize and mix again, then add starch to obtain an initial gel mixture; the initial gel mixture is aged, crystallized, and the crystallized solid product is separated, washed, dried and calcined to obtain the ZSM-48 molecular sieves with mesopore-micropore hierarchical structure. The preparation method has the advantages of simplicity, environmental friendliness and low cost. However, the defects of the technology or the deficiencies of the technology relative to the present application include that starch is used as a mesopore pore former, the molecular weight is large, the pore channel is easily blocked by coking during calcination, and the crystallization time is as long as 4-15 days.

[0008] CN 115108563 A discloses a ZSM-48 molecular sieve and a preparation method thereof, a low-carbon alkane isomerization catalyst and a preparation method and application thereof. The preparation method of the ZSM-48 molecular sieve comprises: (1) mixing an aluminum source, an alkali source, a template agent and deionized water to obtain a solution, and then adding a pore-expanding agent, crystal seeds and a silicon source to the solution to obtain a precursor gel; (2) crystallizing the precursor gel, and then performing alkali treatment on the product obtained by the crystallization. The pore-expanding agent is selected from carbon nanotubes and / or carbon nanofibers. The alkane isomerization catalyst prepared by using the above-prepared ZSM-48 molecular sieve has higher isomerized alkane selectivity and yield in alkane isomerization reactions, especially in low-carbon alkane isomerization reactions, has a wide range of applications, and is particularly suitable for C5-C12 isomerization to improve the octane number of gasoline. However, the defects or disadvantages of the technology relative to the present application include that the product is subjected to alkali treatment after crystallization, the process is complex and difficult to control, the wastewater discharge increases, and the carbon nanotubes and / or carbon nanofibers used as the pore-expanding agent are prone to coking and blocking the pore mouth during the calcination process.

[0009] In summary, at present, the existing technology generally uses pore-forming agents such as starch, polyvinyl alcohol and carbon nanotubes that do not participate in the synthesis of molecular sieves, but the molecular weight of these pore-forming agents is large, the pore-forming effect is limited, and the pore mouth is prone to coking and blocking during the calcination process; or the molecular sieve is embedded in organic starch or polyvinyl alcohol, and the coking of the organic material during the calcination process produces carbon deposition, causing the pore channel of the molecular sieve to be blocked. The selected organic material has a large molecular weight, and the embedding of the molecular sieve therein is not conducive to the dispersion of the metal; in addition, the preparation process of the composite molecular sieve catalyst provided in the existing technology is more complex, for example, it is difficult to accurately control the thickness and uniformity of the other molecular sieves coated outside the ZSM-48 molecular sieve clusters, and it is difficult to control the pore dispersion and acidity.

[0010] Therefore, it has become a technical problem urgently needed to be solved in the field to provide a novel ZSM-48 molecular sieve and a preparation method thereof, an isomerization dewaxing catalyst and a preparation method and application thereof. SUMMARY

[0011] In order to solve the above-mentioned shortcomings and deficiencies, one object of the present application is to provide a preparation method of a ZSM-48 molecular sieve.

[0012] Another object of the present application is also to provide a ZSM-48 molecular sieve prepared by the above-mentioned preparation method of a ZSM-48 molecular sieve.

[0013] Still another object of the present application is also to provide an isomerization dewaxing catalyst, wherein the carrier particles contain the above-mentioned ZSM-48 molecular sieve.

[0014] Still another object of the present application is also to provide a preparation method of the above-mentioned isomerization dewaxing catalyst.

[0015] A further object of the present application is also to provide the use of the isomerization dewaxing catalyst as described above in the preparation of lubricating oil from heavy feedstock by hydroisomerization.

[0016] To achieve the above object, in one aspect, the present application provides a preparation method of ZSM-48 molecular sieve, wherein the preparation method of ZSM-48 molecular sieve comprises:

[0017] Step one: uniformly mix an aluminum source, a silicon source, an alkali source, a crystallization inducer, a template agent, deionized water, a pore-forming agent, and a charge balancing agent to obtain a gel solution;

[0018] wherein the molar ratio of the aluminum source calculated based on Al2O3, the alkali source calculated based on OH - , the template agent, H2O, and the silicon source calculated based on SiO2 is 0.0025-0.02:0.006-0.38:0.11-1.5:10-50:1, preferably 0.005-0.01:0.015-0.25:0.2-1:20-40:1;

[0019] the molar ratio of the pore-forming agent to the silicon source calculated based on SiO2 is 0.01-0.2:1, preferably 0.01-0.1:1;

[0020] the molar ratio of the crystallization inducer calculated based on M2O to the silicon source calculated based on SiO2 is 0.002-0.2:1, preferably 0.005-0.03:1, wherein M is one or more of alkali metals;

[0021] the molar ratio of the charge balancing agent to H2O is 0.1-1:1, preferably 0.2-0.5:1;

[0022] Step two: sequentially pre-crystallize the gel solution at 70-90℃ for 2-6h, crystallize at 120-140℃ for 2-6h, and crystallize at 140-170℃ for 10-48h to obtain a crystallization product;

[0023] Step three: wash, dry, and calcine the crystallization product to obtain a molecular sieve precursor;

[0024] Step four: mix the molecular sieve precursor with an ammonium salt, and then wash, dry, and calcine to obtain the ZSM-48 molecular sieve.

[0025] As a specific embodiment of the above preparation method of the present application, the aluminum source comprises one or a combination of several of aluminum sulfate, sodium aluminate, aluminum nitrate, etc., preferably aluminum sulfate;

[0026] the silicon source comprises one or a combination of several of silica sol, white carbon black, tetraethyl orthosilicate, etc., preferably silica sol;

[0027] The alkali source includes NaOH and / or KOH, etc.

[0028] As a specific embodiment of the above preparation method of the present application, the template agent includes a first template agent and a second template agent, and the molar ratio of the first template agent to the second template agent is 1-400:1, preferably 50-150:1.

[0029] As a specific embodiment of the above preparation method of the present application, the first template agent includes one or a combination of cyclohexylamine, dodecylamine, 1,6-hexanediamine, 1,8-octanediamine, and benzylamine, preferably 1,6-hexanediamine, and the second template agent includes one or a combination of hexamethonium chloride, hexadimethrine bromide, ammonium oxalate, ammonium acetate, and benzyltriethylammonium bromide, preferably hexamethonium chloride.

[0030] As a specific embodiment of the above preparation method of the present application, the ammonium salt includes one or a combination of ammonium chloride, ammonium nitrate, and ammonium sulfate, preferably ammonium chloride.

[0031] As a specific embodiment of the above preparation method of the present application, the crystallization inducer includes one or a combination of sodium chloride, potassium chloride, sodium sulfate, potassium sulfate, etc., preferably potassium chloride.

[0032] As a specific embodiment of the above preparation method of the present application, the pore-forming agent includes one or a combination of P123, Triton-100, polyhexamethylene biguanide, ammonium chloride, polyvinyl alcohol, etc., preferably P123.

[0033] As a specific embodiment of the above preparation method of the present application, the relative molecular weight of the P123 is 4000-8000.

[0034] As a specific embodiment of the above preparation method of the present application, the charge balancing agent includes one or a combination of alcohol charge balancing agents such as glycerol, ethylene glycol, isopropyl alcohol, propyl alcohol, and 2-butanol, preferably glycerol.

[0035] As a specific embodiment of the above preparation method of the present application, in step one, the amount of the pore-forming agent is within 5wt% of the total weight of the gel solution.

[0036] As a specific embodiment of the above preparation method of the present application, in step one, the amount of the crystallization inducer calculated as M2O is within 5wt% of the total weight of the gel solution.

[0037] As a specific embodiment of the above preparation method of the present application, in step one, the mixing is performed at 40-60°C.

[0038] As a specific embodiment of the above preparation method of the present application, in step three, the calcination is performed at 500-600°C for 6-30 hours.

[0039] As a specific embodiment of the above preparation method of the present application, in step four, the mixing is performed at 70-80°C for 4-6 hours.

[0040] As a specific embodiment of the above preparation method of the present application, in step four, the calcination is performed at 500-600°C for 6-40 hours, preferably 6-30 hours.

[0041] In the above preparation method of the ZSM-48 molecular sieve, the washing and drying are conventional operations, and the operation steps and the process parameters involved in the washing and drying can be adjusted according to the actual operation needs.

[0042] In another aspect, the present application further provides a ZSM-48 molecular sieve, wherein the ZSM-48 molecular sieve is prepared by the above preparation method of the ZSM-48 molecular sieve.

[0043] As a specific embodiment of the above ZSM-48 molecular sieve, the length of the crystal grains of the ZSM-48 molecular sieve is 0.1-0.5 μm, the diameter of the crystal grains is 50-100 nm, and the axial diameter ratio is 2-10. In the present application, the axial diameter ratio is the ratio of the length of the crystal grains of the molecular sieve to the width of the cross section.

[0044] In another aspect, the present application further provides an isodewaxing catalyst comprising carrier particles and a noble metal active component supported on the carrier particles, wherein the carrier particles comprise the above ZSM-48 molecular sieve, and the loading amount of the noble metal active component is 0.1-0.5 wt% of the mass of the carrier particles.

[0045] As a specific embodiment of the above isodewaxing catalyst, the noble metal active component comprises platinum and / or palladium, etc.

[0046] As a specific embodiment of the above isodewaxing catalyst, the carrier particles are prepared by mixing the ZSM-48 molecular sieve, alumina, titania, an acid solution, a binder, and deionized water uniformly, and then extruding, drying, and calcining.

[0047] The mass ratio of ZSM-48 molecular sieve, alumina, titanium dioxide, acid solution, binder, deionized water is 1:0.3-9:0.01-0.5:0.01-0.6:0.3-1:0.2-1, preferably 1:0.5-2:0.02-0.05:0.02-0.5:0.5-0.8:0.5-0.8.

[0048] As a specific embodiment of the isodewaxing catalyst described above, the binder comprises pearl millet powder and / or methyl cellulose, preferably pearl millet powder; the acid solution comprises a nitric acid or phosphoric acid solution with a concentration of 5-15wt%, preferably nitric acid; and the alumina is a common alumina such as pseudo-boehmite.

[0049] As a specific embodiment of the isodewaxing catalyst described above, the carrier particles are prepared by uniformly mixing the ZSM-48 molecular sieve, alumina, titanium dioxide, acid solution, binder, and deionized water, and then extruding, drying, and calcining at 400-500℃ for 6-14 hours.

[0050] In another aspect, the application further provides a preparation method of the isodewaxing catalyst described above, wherein the preparation method comprises:

[0051] Step (1): dissolving a noble metal salt in a mixture of water, alcohol, and ligand, and uniformly mixing to obtain a noble metal precursor solution;

[0052] Step (2): immersing the carrier particles in the noble metal precursor solution, and then drying and calcining the immersed product to obtain the isodewaxing catalyst.

[0053] As a specific embodiment of the preparation method of the isodewaxing catalyst described above, the noble metal salt comprises one or a combination of hexahydrated chloroplatinic acid, palladium chloride, platinum dichloride, and ammonium hexachloroplatinate, preferably hexahydrated chloroplatinic acid.

[0054] As a specific embodiment of the preparation method of the isodewaxing catalyst described above, the ligand comprises one or a combination of sorbic acid, salicylic acid, nicotinamide, lactic acid, citric acid, and hyaluronic acid, and the molar ratio of ligand to noble metal atom is 6-18:1. During the preparation of the isodewaxing catalyst, the ligand is complexed with the noble metal atom and loaded on the carrier, which is conducive to the dispersion of the noble metal atom, and the presence of the ligand can also hinder the aggregation of the noble metal to form large particles to some extent.

[0055] As a specific embodiment of the above-mentioned preparation method of the isodewaxing catalyst, in the step (1), the mixing is performed at 30-60℃ for 2-6h.

[0056] As a specific embodiment of the above-mentioned preparation method of the isodewaxing catalyst, in the step (1), the mixing is performed at 30-60℃ for 2-6h.

[0057] As a specific embodiment of the above-mentioned preparation method of the isodewaxing catalyst, in the step (2), the calcination is performed at 400-600℃ for 4-14h in an air atmosphere, preferably at 400-500℃ for 6-14h.

[0058] In the preparation method of the isodewaxing catalyst, the extruding, drying and baking are all conventional operations, and the operation steps and the process parameters involved can be adjusted according to the actual operation needs.

[0059] In the last aspect, the application further provides the application of the above-mentioned isodewaxing catalyst in the preparation of lubricating oil from heavy feedstock by hydroisomerization.

[0060] As a specific embodiment of the above-mentioned application, the heavy feedstock includes F-T wax or hydrocracking tail oil.

[0061] Compared with the prior art, the application has the following beneficial technical effects:

[0062] 1) The application uses a crystallization inducer in the preparation of ZSM-48 molecular sieve, which can induce more crystal nuclei to form rapidly, greatly shorten the crystallization time, reduce the crystal size, i.e. form more small crystal molecular sieve, so that the length of the crystal is only 0.1-0.5μm. When the isodewaxing catalyst (the carrier particles of which contain the above-mentioned ZSM-48 molecular sieve) is used for the preparation of lubricating oil by hydroisomerization, it is beneficial for the product to diffuse out of the pore, so that the cracking reaction can be reduced;

[0063] 2) The present application uses alcohol as charge balancing agent in the preparation of ZSM-48 molecular sieve, alcohol is dissolved in water, and the molecular size is between water molecules and structure directing agent (i.e. template, including first template and second template), which can enter the channel, and in the process of molecular sieve synthesis, it can replace part of water molecules to support / fill the channel, the hydroxyl group contained in alcohol forms hydrogen bond with the inorganic anion framework of molecular sieve, maintains the charge balance in the channel, makes more water molecules in the system play the role of solvent (equivalent to the increase of water phase), and the fluidity is enhanced, the crystal grains are uniformly dispersed in the solvent, and it is easier to form small crystal molecular sieve, i.e. it is beneficial to the formation of small crystal; in addition, the alcohol as charge balancing agent does not change the pH value of the system, thereby avoiding the generation of impurities, and the added charge balancing agent is also beneficial to the uniform distribution of acid sites of the molecular sieve, when the isomerization dewaxing catalyst (the carrier particles of which contain the above-mentioned ZSM-48 molecular sieve) is used for the preparation of lubricating oil by hydroisomerization, the reaction efficiency can be improved;

[0064] 3) The present application uses pore forming agent in the preparation of ZSM-48 molecular sieve, mesopores and micropores can be directly formed in the process of molecular sieve synthesis, when the isomerization dewaxing catalyst (the carrier particles of which contain the above-mentioned ZSM-48 molecular sieve) is used for the preparation of lubricating oil by hydroisomerization, it is beneficial to the diffusion of reactants and products in the channel, i.e. the diffusion efficiency of reactants and products can be improved, the reaction efficiency, isomerization conversion rate, cracking rate can be improved, and the amount of molecular sieve in the catalyst can be reduced;

[0065] 4) In the preparation of ZSM-48 molecular sieve, the gel solution is pre-crystallized at 70-90℃ for 2-6h, crystallized at 120-140℃ for 2-6h, and crystallized at 140-170℃ for 10-48h, wherein the first stage crystallization forms primary structure, and the second stage crystallization forms more crystal nucleus, which is beneficial to the rapid growth of small crystal under the condition of the third stage crystallization temperature, the small crystal molecular sieve has short channel length, which is beneficial to the rapid diffusion of reaction products out of the channel and reduces the secondary cracking reaction;

[0066] 5) The preparation method of the present application can directly synthesize short-axis ZSM- molecular sieve, shorten the channel length, and when the isomerization dewaxing catalyst (the carrier particles of which contain the above-mentioned ZSM-48 molecular sieve) is used for the preparation of lubricating oil by hydroisomerization, the reaction efficiency can be significantly improved. BRIEF DESCRIPTION OF DRAWINGS

[0067] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed in the embodiment description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0068] Figure 1 XRD pattern of molecular sieve A1 provided for Example 1 of the present invention.

[0069] Figure 2 SEM pattern of molecular sieve A1 provided for Example 1 of the present invention.

[0070] Figure 3 XRD pattern of molecular sieve A6 provided for Comparative Example 1.

[0071] Figure 4 SEM pattern of molecular sieve A6 provided for Comparative Example 1.

[0072] Figure 5 XRD pattern of molecular sieve A8 provided for Comparative Example 3.

[0073] Figure 6 SEM pattern of molecular sieve A8 provided for Comparative Example 3.

[0074] Figure 7 XRD pattern of molecular sieve A10 provided for Comparative Example 5.

[0075] Figure 8 XRD pattern of molecular sieve A11 provided for Comparative Example 6. DETAILED DESCRIPTION

[0076] It has to be noted that, as used herein, the terms "includes" and "including", as well as their synonyms, such as "comprising", "comprises" and "comprised of", when used in this specification, specify the presence of stated features, integers, steps, processes, actions, elements, or components, but do not preclude the presence or addition of one or more other features, integers, steps, processes, actions, elements, components, or groups thereof.

[0077] The ranges disclosed herein are given using the "from" and "to" format. One or more of the lower and upper limits are finite and one or more of the lower and upper limits are infinite. The ranges are inclusive. The ranges are also interchangeable with the corresponding "from" and "to" format. For example, a range of 60-120 is interchangeable with a range of 60-120 inclusive. A range of 60-120 inclusive is also interchangeable with a range of 60-120. A range of 60-120 is also interchangeable with a range of 60-120 inclusive.

[0078] In the present application, unless otherwise stated, the numerical range "a-b" represents a shorthand for the inclusion of any integer falling within the given range of a to b, wherein a and b are integers. For example, the numerical range "0-5" indicates that all integers between 0 and 5 inclusive have been expressly stated as being part of the present application. "0-5" is a shorthand for "0, 1, 2, 3, 4, and 5".

[0079] In the present application, unless otherwise stated, all embodiments mentioned in the present application and preferred embodiments can be combined with each other to form new technical solutions.

[0080] In the present application, unless otherwise stated, all technical features mentioned in the present application and preferred features can be combined with each other to form new technical solutions.

[0081] In the present application, unless otherwise stated, all steps mentioned in the present application can be performed in sequence or randomly, but preferably in sequence. For example, the method comprises steps (a) and (b) indicates that the method can comprise steps (a) and (b) performed in sequence, or steps (b) and (a) performed in sequence. For example, the method further comprises step (c) indicates that step (c) can be added to the method in any sequence. For example, the method can comprise steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.

[0082] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in combination with the accompanying tables, drawings and examples. The following described examples are part of the examples of the present application, but not all the examples, and are only used to illustrate the present application, and should not be regarded as limiting the scope of the present application. Based on the examples in the present application, all other examples obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present application. The specific conditions not mentioned in the examples are carried out according to the conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments not mentioned by the manufacturer are all conventional products that can be purchased on the market.

[0083] Examples and comparative examples of ZSM-48 molecular sieve

[0084] Example 1

[0085] The present example provides a ZSM-48 molecular sieve, which is prepared by a preparation method comprising the following specific steps:

[0086] Step one: 3.22 g aluminum sulfate, 36 g silica sol (40 wt% solid content), 0.06 g NaOH, 0.06 g NaCl, 4.7 g hexadimethrine bromide, 1.4 g cyclohexylamine, 24 g deionized water, 0.74 g Triton X-100, 24 g glycerol were mixed uniformly at a temperature of 40°C to obtain a gel solution;

[0087] wherein the molar ratio of the aluminum source calculated based on Al2O3, the alkali source calculated based on OH - , the template agent, H2O and the silicon source calculated based on SiO2 is 0.02:0.006:0.11:10:1;

[0088] The molar ratio of the pore-forming agent to the silicon source calculated based on SiO2 is 0.01:1;

[0089] The molar ratio of the crystallization inducer calculated based on Na2O to the silicon source calculated based on SiO2 is 0.002:1;

[0090] The molar ratio of the charge balancing agent to H2O is 0.1:1;

[0091] The molar ratio of the cyclohexylamine to the hexadimethrine bromide is 1:1;

[0092] Step two: the gel solution was pre-crystallized at 70°C for 2 h, crystallized at 120°C for 2 h, and crystallized at 140°C for 48 h in sequence to obtain a crystallization product;

[0093] Step three: the crystallization product was washed, dried and calcined at 500°C for 6 hours to obtain a molecular sieve precursor;

[0094] Step four: the molecular sieve precursor was mixed with ammonium chloride at 70°C for 4 h, and then washed, dried and calcined at 500°C for 6 hours to obtain the ZSM-48 molecular sieve, which is denoted as molecular sieve A1.

[0095] Example 2

[0096] The present example provides a ZSM-48 molecular sieve, which is prepared by a preparation method comprising the following specific steps:

[0097] Step one: 0.49 g sodium metaaluminate, 18 g white carbon black, 0.48 g NaOH, 1.06 g sodium sulfate, 0.05 g hexamethonium chloride, 5.4 g 1.8-octanediamine, 81 g deionized water, 4.7 g polyhexamethylene biguanide, 275 g ethylene glycol were mixed uniformly at a temperature of 60°C to obtain a gel solution;

[0098] wherein the molar ratio of the aluminum source calculated based on Al2O3, the alkali source calculated based on OH - , the template agent, H2O and the silicon source calculated based on SiO2 is 0.02:0.04:0.12:15:1;

[0099] the molar ratio of the pore-forming agent to the silicon source calculated as SiO2 is 0.07:1;

[0100] the molar ratio of the crystallization inducer calculated as Na2O to the silicon source calculated as SiO2 is 0.02:1;

[0101] the molar ratio of the charge balancing agent to H2O is 0.98:1;

[0102] the molar ratio of the first template agent to the second template agent is 204:1;

[0103] Step two: the gel solution is sequentially pre-crystallized at 90°C for 6h, crystallized at 140°C for 6h, and crystallized at 170°C for 10h to obtain a crystallized product;

[0104] Step three: the crystallized product is washed, dried, and calcined at 600°C for 30h to obtain a molecular sieve precursor;

[0105] Step four: the molecular sieve precursor is mixed with ammonium chloride at 80°C for 6h, and then washed, dried, and calcined at 600°C for 30h to obtain a ZSM-48 molecular sieve, which is denoted as molecular sieve A2.

[0106] Example 3

[0107] The present example provides a ZSM-48 molecular sieve, which is prepared by a preparation method comprising the following specific steps:

[0108] Step one: 0.32g of aluminum nitrate, 18g of tetraethyl orthosilicate, 1g of KOH, 2.58g of KCl, 0.2g of ammonium oxalate, 16g of 1,6-hexanediamine, 62.3g of deionized water, 5.1g of triton X-100, and 100g of isopropanol are uniformly mixed at a temperature of 45°C to obtain a gel solution;

[0109] wherein the molar ratio of the aluminum source calculated as Al2O3, the alkali source calculated as OH - KOH, the template agent, H2O, and the silicon source calculated as SiO2 is 0.01:0.2:1.5:40:1;

[0110] the molar ratio of the pore-forming agent to the silicon source calculated as SiO2 is 0.2:1;

[0111] the molar ratio of the crystallization inducer calculated as K2O to the silicon source calculated as SiO2 is 0.2:1;

[0112] the molar ratio of the charge balancing agent to H2O is 0.48:1;

[0113] the molar ratio of the first template agent to the second template agent is 85:1;

[0114] Step two: the gel solution was pre-crystallized at 80℃ for 4h, crystallized at 130℃ for 4h, and crystallized at 160℃ for 20h to obtain a crystallized product;

[0115] Step three: the crystallized product was washed, dried and calcined at 550℃ for 20h to obtain a molecular sieve precursor;

[0116] Step four: the molecular sieve precursor was mixed with ammonium chloride at 75℃ for 4h, and then washed, dried and calcined at 530℃ for 24h to obtain the ZSM-48 molecular sieve, which is denoted as molecular sieve A3.

[0117] Example 4

[0118] The present example provides a ZSM-48 molecular sieve, which is prepared by a preparation method comprising the following specific steps:

[0119] Step one: 0.12g of aluminum nitrate, 18g of silica sol (40wt% solid content), 1.86g of NaOH, 0.43g of potassium sulfate, 0.1g of benzyltriethylammonium bromide, 10g of benzylamine, 100g of deionized water, 7.2g of P123, and 46g of 2-butanol were uniformly mixed at a temperature of 50℃ to obtain a gel solution;

[0120] The molar ratio of the aluminum source calculated based on Al2O3, the alkali source calculated based on OH - , the template agent, H2O and the silicon source calculated based on SiO2 is 0.0026:0.38:0.76:50:1;

[0121] The molar ratio of the pore-forming agent to the silicon source calculated based on SiO2 is 0.01:1;

[0122] The molar ratio of the crystallization inducer calculated based on K2O to the silicon source calculated based on SiO2 is 0.02:1;

[0123] The molar ratio of the charge balancing agent to H2O is 0.1:1;

[0124] The molar ratio of the first template agent to the second template agent is 254:1;

[0125] Step two: the gel solution was pre-crystallized at 85℃ for 5h, crystallized at 135℃ for 5h, and crystallized at 160℃ for 30h to obtain a crystallized product;

[0126] Step three: the crystallized product was washed, dried and calcined at 530℃ for 12h to obtain a molecular sieve precursor;

[0127] Step four: the molecular sieve precursor was mixed with ammonium nitrate at 70℃ for 4h, and then washed, dried and calcined at 560℃ for 28h to obtain the ZSM-48 molecular sieve, which is denoted as molecular sieve A4.

[0128] Example 5

[0129] This example provides a ZSM-48 molecular sieve which is prepared by a preparation method comprising the following specific steps:

[0130] Step one: 0.15 g of aluminum nitrate nonahydrate, 18 g of silica sol (solid content 40%), 1.2 g of NaOH, 0.5 g of K2SO4, 10 g of dodecylamine, 0.1 g of ammonium acetate, 80 g of deionized water, 0.2 g of ammonium chloride, 50 g of propanol are uniformly mixed at a temperature of 43°C to obtain a gel solution;

[0131] wherein the molar ratio of the aluminum source calculated as Al2O3, the alkali source calculated as OH - , the template agent, H2O and the silicon source calculated as SiO2 is 0.0033:0.25:0.46:42.1:1;

[0132] The molar ratio of the pore-forming agent to the silicon source calculated as SiO2 is 0.03:1;

[0133] The molar ratio of the crystallization inducer calculated as K2O to the silicon source calculated as SiO2 is 0.024:1;

[0134] The molar ratio of the charge balancing agent to H2O is 0.165:1;

[0135] The molar ratio of the first template agent to the second template agent is 41.59:1;

[0136] Step two: the gel solution is sequentially pre-crystallized at 80°C for 4 h, crystallized at 130°C for 4 h, and crystallized at 160°C for 20 h to obtain a crystallization product;

[0137] Step three: the crystallization product is washed, dried and calcined at 550°C for 20 hours to obtain a molecular sieve precursor;

[0138] Step four: the molecular sieve precursor is mixed with ammonium sulfate at 75°C for 4 h, and then washed, dried and calcined at 530°C for 24 hours to obtain the ZSM-48 molecular sieve, which is denoted as molecular sieve A5.

[0139] Comparative Example 1

[0140] This comparative example provides a ZSM-48 molecular sieve which is prepared by a preparation method comprising the following specific steps:

[0141] Step one: 0.32 g of aluminum nitrate, 18 g of tetraethyl orthosilicate, 1 g of KOH, 0.2 g of ammonium oxalate, 16 g of 1,6-hexanediamine, 62.3 g of deionized water, 5.1 g of triton X-100, 100 g of isopropanol are uniformly mixed at a temperature of 45°C to obtain a gel solution;

[0142] wherein the molar ratio of the aluminum source calculated as Al203, the alkali source calculated as OH - -1.5:40:1;

[0143] the molar ratio of the pore forming agent to the silicon source calculated as Si02 is 0.2:1;

[0144] the molar ratio of the charge balancing agent to H20 is 0.48:1;

[0145] the molar ratio of the first template to the second template is 85:1;

[0146] Step two: the gel solution is sequentially pre-crystallized at 80°C for 4h, crystallized at 130°C for 4h, and crystallized at 160°C for 20h to obtain a crystallized product;

[0147] Step three: the crystallized product is washed, dried, and calcined at 550°C for 20h to obtain a molecular sieve precursor;

[0148] Step four: the molecular sieve precursor is mixed with ammonium chloride at 75°C for 4h, and then washed, dried, and calcined at 530°C for 24h to obtain the ZSM-48 molecular sieve, which is denoted as molecular sieve A6.

[0149] Comparative Example 2

[0150] This comparative example provides a ZSM-48 molecular sieve, which is prepared by a preparation method comprising the following specific steps:

[0151] Step one: 0.32g of aluminum nitrate, 18g of tetraethyl orthosilicate, 1g of KOH, 1.3g of KCl, 0.2g of ammonium oxalate, 16g of 1,6-hexanediamine, and 62.3g of deionized water are uniformly mixed at a temperature of 45°C to obtain a gel solution;

[0152] wherein the molar ratio of the aluminum source calculated as Al203, the alkali source calculated as OH - -1.5:40:1;

[0153] the molar ratio of the crystallization inducer calculated as K20 to the silicon source calculated as Si02 is 0.1:1;

[0154] the molar ratio of the first template to the second template is 85:1;

[0155] Step two: the gel solution is sequentially pre-crystallized at 80°C for 4h, crystallized at 130°C for 4h, and crystallized at 160°C for 20h to obtain a crystallized product;

[0156] Step three: the crystallized product is washed, dried, and calcined at 550°C for 20h to obtain a molecular sieve precursor;

[0157] Step four: the molecular sieve precursor was mixed with ammonium chloride at 75 °C for 4 h, and then washed, dried and calcined at 530 °C for 24 hours to obtain the ZSM-48 molecular sieve, which is denoted as molecular sieve A7.

[0158] Comparative Example 3

[0159] This comparative example provides a ZSM-48 molecular sieve, which is prepared by a preparation method comprising the following specific steps:

[0160] Step one: 0.32 g of aluminum nitrate, 18 g of tetraethyl orthosilicate, 1 g of KOH, 1.3 g of KCl, 0.2 g of ammonium oxalate, 16 g of 1,6-hexanediamine, 5.1 g of triton X-100, and 62.3 g of deionized water were uniformly mixed at a temperature of 45 °C to obtain a gel solution;

[0161] The molar ratio of the aluminum source calculated based on Al2O3, the alkali source calculated based on OH - , the template agent, H2O and the silicon source calculated based on SiO2 is 0.01:0.2:1.5:40:1;

[0162] The molar ratio of the pore-forming agent to the silicon source calculated based on SiO2 is 0.2:1;

[0163] The molar ratio of the crystallization inducer calculated based on K2O to the silicon source calculated based on SiO2 is 0.1:1;

[0164] The molar ratio of the first template agent to the second template agent is 85:1;

[0165] Step two: the gel solution was sequentially pre-crystallized at 80 °C for 4 h, crystallized at 130 °C for 4 h, and crystallized at 160 °C for 20 h to obtain a crystallization product;

[0166] Step three: the crystallization product was washed, dried and calcined at 550 °C for 20 hours to obtain a molecular sieve precursor;

[0167] Step four: the molecular sieve precursor was mixed with ammonium chloride at 75 °C for 4 h, and then washed, dried and calcined at 530 °C for 24 hours to obtain the ZSM-48 molecular sieve, which is denoted as molecular sieve A8.

[0168] Comparative Example 4

[0169] This comparative example provides a ZSM-48 molecular sieve, which is prepared by a preparation method comprising the following specific steps:

[0170] Step one: 0.32 g aluminum nitrate, 18 g tetraethyl orthosilicate, 1 g KOH, 1.3 g KCl, 0.2 g ammonium oxalate, 16 g 1,6-hexanediamine, 62.3 g deionized water, 5.1 g triton X-100, 100 g isopropyl alcohol were mixed uniformly at a temperature of 45°C to obtain a gel solution;

[0171] wherein the molar ratio of the aluminum source calculated based on Al2O3, the alkali source calculated based on OH - , the template agent, H2O and the silicon source calculated based on SiO2 is 0.01:0.2:1.5:40:1;

[0172] the molar ratio of the pore-forming agent to the silicon source calculated based on SiO2 is 0.2:1;

[0173] the molar ratio of the crystallization inducer calculated based on K2O to the silicon source calculated based on SiO2 is 0.1:1;

[0174] the molar ratio of the charge balancing agent to H2O is 0.48:1;

[0175] the molar ratio of the first template agent to the second template agent is 85:1;

[0176] Step two: the gel solution was crystallized at 160°C for 28 h to obtain a crystallization product;

[0177] Step three: the crystallization product was washed, dried and calcined at 550°C for 20 h to obtain a molecular sieve precursor;

[0178] Step four: the molecular sieve precursor was mixed with ammonium chloride at 75°C for 4 h, and then washed, dried and calcined at 530°C for 24 h to obtain the ZSM-48 molecular sieve, which is denoted as molecular sieve A9.

[0179] Comparative Example 5

[0180] The present example provides a ZSM-48 molecular sieve, which is prepared by a preparation method comprising the following specific steps:

[0181] Step one: 3.22 g aluminum sulfate, 36 g silica sol (40 wt% solid content), 0.06 g NaOH, 0.06 g NaCl, 4.7 g hexamethonium bromide, 1.4 g cyclohexylamine, 24 g deionized water, 0.74 g triton X-100, 48 g bis(cyclopentadiene) cobalt were mixed uniformly at a temperature of 40°C to obtain a gel solution;

[0182] wherein the molar ratio of the aluminum source calculated based on Al2O3, the alkali source calculated based on OH - , the template agent, H2O and the silicon source calculated based on SiO2 is 0.02:0.006:0.11:10:1;

[0183] The molar ratio of the pore-forming agent to the silicon source calculated as SiO2 is 0.01:1;

[0184] The molar ratio of the crystallization inducer calculated as Na2O to the silicon source calculated as SiO2 is 0.002:1;

[0185] The molar ratio of the charge balancing agent to H2O is 0.1:1;

[0186] The molar ratio of the cyclohexylamine to the hexamehtonium bromide is 1:1;

[0187] Step two: the gel solution is pre-crystallized at 70°C for 2h, crystallized at 120°C for 2h, and crystallized at 140°C for 48h in sequence to obtain a crystallized product;

[0188] Step three: the crystallized product is washed, dried, and calcined at 500°C for 6h to obtain a molecular sieve precursor;

[0189] Step four: the molecular sieve precursor is mixed with ammonium chloride at 70°C for 4h, and then washed, dried, and calcined at 500°C for 6h to obtain the ZSM-48 molecular sieve, which also contains ZSM-5 heterocrystals and amorphous silica-alumina, denoted as molecular sieve A10.

[0190] Comparative Example 6

[0191] The present example provides a ZSM-48 molecular sieve, which is prepared by a preparation method comprising the following specific steps:

[0192] Step one: 3.22g of aluminum sulfate, 36g of silica sol (40wt% solid content), 0.06g of NaOH, 0.06g of NaCl, 4.7g of hexamehtonium bromide, 1.4g of cyclohexylamine, 24g of deionized water, 0.74g of triton X-100, and 29.3g of 1,6-hexanediamine are uniformly mixed at a temperature of 40°C to obtain a gel solution;

[0193] The molar ratio of the aluminum source calculated as Al2O3, the alkali source calculated as OH - The molar ratio of the aluminum source calculated as Al2O3, the alkali source calculated as OH

[0194] The molar ratio of the pore-forming agent to the silicon source calculated as SiO2 is 0.01:1;

[0195] The molar ratio of the crystallization inducer calculated as Na2O to the silicon source calculated as SiO2 is 0.002:1;

[0196] The molar ratio of the charge balancing agent to H2O is 0.1:1;

[0197] The molar ratio of the cyclohexylamine to the hexamehtonium bromide is 1:1;

[0198] Step two: the gel solution is pre-crystallized at 70°C for 2h, crystallized at 120°C for 2h, and crystallized at 140°C for 48h to obtain a crystallized product;

[0199] Step three: the crystallized product is washed, dried and calcined at 500°C for 6h to obtain a molecular sieve precursor;

[0200] Step four: the molecular sieve precursor is mixed with ammonium chloride at 70°C for 4h, and then washed, dried and calcined at 500°C for 6h to obtain the ZSM-48 molecular sieve containing ZSM-5 heterocrystals and amorphous silica-alumina, which is denoted as molecular sieve A11.

[0201] The total BET specific surface area, micropore specific surface area and mesopore specific surface area of the molecular sieves A1-A11 provided by Examples 1-5 and Comparative Examples 1-6 of the present application are shown in Table 1 below, respectively.

[0202] Table 1

[0203]

[0204] As can be seen from Table 1 above, the molecular sieves A1-A11 provided by Examples 1-5 and Comparative Examples 1-6 of the present application all have micropores and mesopores, but the total BET specific surface area and mesopore specific surface area of the molecular sieves prepared in the comparative examples are significantly lower than those of the molecular sieves provided by the examples of the present application.

[0205] The XRD pattern and SEM pattern of the molecular sieve A1 provided by Example 1 of the present application are shown in Figure 1 and Figure 2 respectively, the XRD pattern and SEM pattern of the molecular sieve A6 provided by Comparative Example 1 are shown in Figure 3 and Figure 4 respectively, the XRD pattern and SEM pattern of the molecular sieve A8 provided by Comparative Example 3 are shown in Figure 5 and Figure 6 respectively, the XRD pattern of the molecular sieve A10 provided by Comparative Example 5 is shown in Figure 7 , and the XRD pattern of the molecular sieve A11 provided by Comparative Example 6 is shown in Figure 8 . As can be seen from Figure 1 , Figure 3 and Figure 5 , the molecular sieves A1, A6 and A8 are all pure-phase ZSM-48 molecular sieves without the formation of heterocrystals. However, as can be seen from Figure 2 , the length of the crystal grains of the molecular sieve A1 is 100-500nm, the diameter of the crystal grains is 50-100nm, and the ratio of the axial diameter is about 2-10, indicating that it is a short-axle ZSM-48 molecular sieve, while in comparison Figure 2 , Figure 4 and Figure 6and the experimental data in Table 1 can be seen that, compared with the molecular sieve A1 provided in Example 1, the crystal grain size and axial diameter ratio of the molecular sieves A6-A11 provided in Comparative Examples 1-6 are larger. From the above, it can be seen that, compared with the molecular sieve A1 provided in Example 1, the crystal grain size and axial diameter ratio of the molecular sieves A10-A11 provided in Comparative Examples 5-6 are larger. Figure 7 and Figure 8 It can be seen that, in Comparative Examples 5 and 6, non-alcohol charge balancing agents such as organic metal complexes (bis(cyclopentadiene) cobalt) and organic amines (1,6-hexanediamine) are added to prepare the molecular sieve, which can affect the pH value or structure of the system, and is easy to produce heterocrystal or amorphous.

[0206] In summary, it can be seen from the molecular sieves A1 provided in Comparative Example 1 and the molecular sieves A10-A11 provided in Comparative Examples 5-6 that, compared with the bis(cyclopentadiene) cobalt and 1,6-hexanediamine charge balancing agents used in Comparative Examples 5 and 6, the use of glycerol and other alcohol charge balancing agents in Example 1 can obtain a pure-phase molecular sieve, and the crystal grain size and axial diameter ratio of the molecular sieve are smaller.

[0207] Isomerization dewaxing catalyst examples and comparative examples

[0208] Example 6

[0209] The present example provides an isomerization dewaxing catalyst, which is prepared by a preparation method comprising the following specific steps:

[0210] Step (1): 100 g of the molecular sieve A1, 30 g of pseudoboehmite, 1 g of titanium dioxide, 1 g of nitric acid solution (5 wt%), 30 g of sesbania powder, and 20 g of deionized water are uniformly mixed, extruded, dried, and calcined at 400°C for 6 hours to obtain carrier particles;

[0211] The mass ratio of each component is: molecular sieve A1: alumina: titanium dioxide: acid solution: binder: deionized water = 1:0.3:0.01:0.01:0.3:0.2;

[0212] Step (2): 1.32 g of chloroplatinic acid hexahydrate is dissolved in a mixture of 25 g of water, 25 g of ethanol, and 1.74 g of sorbic acid ligand, and mixed at a temperature of 30°C for 2 h to obtain a noble metal precursor solution, and the molar ratio of sorbic acid to platinum atoms is 6:1;

[0213] Step (3): 100 g of the carrier particles are immersed in the noble metal precursor solution for 2 h, and after the immersion is completed, the particles are dried at 100°C for 2 h, and then calcined at 400°C for 6 hours in an air atmosphere to obtain an isomerization dewaxing catalyst, and the loading amount of noble metal is 0.5 wt%, which is denoted as catalyst C1.

[0214] Example 7

[0215] The embodiment provides an isomerization dewaxing catalyst which is prepared by a preparation method comprising the following specific steps:

[0216] Step (1): 10 g of molecular sieve A2, 90 g of pseudo-boehmite, 5 g of titanium dioxide, 6 g of phosphoric acid solution (15 wt%), 10 g of methyl cellulose and 10 g of deionized water are uniformly mixed, extruded, dried, and calcined at 500 DEG C for 14 hours to obtain carrier particles;

[0217] The mass ratio of the components is: molecular sieve A2: alumina: titanium dioxide: acid solution: binder: deionized water = 1:9:0.5:0.6:1:1;

[0218] Step (2): 0.18 g of palladium chloride is dissolved in a mixture of 50 g of water, 1 g of propanol and 2.53 g of salicylic acid ligand solution, and mixed at a temperature of 60 DEG C for 4 h to obtain a noble metal precursor solution, and the molar ratio of salicylic acid to palladium atoms is 18:1;

[0219] Step (3): 100 g of the carrier particles are immersed in the noble metal precursor solution for 4 h, and then dried at a temperature of 120 DEG C for 2 h, and then calcined at 500 DEG C for 14 h in an air atmosphere to obtain an isomerization dewaxing catalyst, and the noble metal loading is 0.5 wt%, and the catalyst is recorded as catalyst C2.

[0220] Embodiment 8

[0221] The embodiment provides an isomerization dewaxing catalyst which is prepared by a preparation method comprising the following specific steps:

[0222] Step (1): 20 g of molecular sieve A3, 100 g of pseudo-boehmite, 4 g of titanium dioxide, 6 g of nitric acid solution (5 wt%), 10 g of sesbania powder and 16 g of deionized water are uniformly mixed, extruded, dried, and calcined at 450 DEG C for 10 hours to obtain carrier particles;

[0223] The mass ratio of the components is: molecular sieve: alumina: titanium dioxide: acid solution: binder: deionized water = 1:5:0.2:0.3:0.5:0.8;

[0224] Step (2): 0.42 g of platinum dichloride is dissolved in a mixture of 50 g of water, 2 g of isopropyl alcohol and 1.71 g of lactic acid ligand solution, and mixed at a temperature of 30 DEG C for 2 h to obtain a noble metal precursor solution, and the molar ratio of lactic acid to platinum atoms is 12:1;

[0225] Step (3): 100 g of the support particles were impregnated in the noble metal precursor solution for 2 h, and after the impregnation was completed, drying was performed at a temperature of 100 °C for 2 h, and then calcination was performed in an air atmosphere at 450 °C for 10 h to obtain an isodewaxing catalyst, the loading amount of the noble metal being 0.3 wt%, which was denoted as catalyst C3.

[0226] Example 9

[0227] This example provides an isodewaxing catalyst, which is prepared by a preparation method comprising the following specific steps:

[0228] Step (1): 100 g of the molecular sieve A4, 50 g of the pseudoboehmite, 5 g of the titanium dioxide, 8 g of the nitric acid solution (5 wt%), 40 g of the sesbania powder, and 30 g of the deionized water were uniformly mixed, and then extruded, dried, and calcined at 480 °C for 12 hours to obtain the support particles;

[0229] The mass ratio of the components was: molecular sieve: alumina: titanium dioxide: acid solution: binder: deionized water = 1:0.5:0.05:0.08:0.4:0.3;

[0230] Step (2): 0.46 g of ammonium hexachloroplatinate was dissolved in a mixture of 40 g of water, 10 g of glycerol, and 1.9 g of the nicotinamide ligand, and the mixture was mixed at a temperature of 30 °C for 2 h to obtain the noble metal precursor solution, the molar ratio of nicotinamide to platinum atoms being 15:1;

[0231] Step (3): 100 g of the support particles were impregnated in the noble metal precursor solution for 2 h, and after the impregnation was completed, drying was performed at a temperature of 100 °C for 2 h, and then calcination was performed in an air atmosphere at 480 °C for 12 h to obtain an isodewaxing catalyst, the loading amount of the noble metal being 0.2 wt%, which was denoted as catalyst C4.

[0232] Example 10

[0233] This example provides an isodewaxing catalyst, which is prepared by a preparation method comprising the following specific steps:

[0234] Step (1): 100 g of the molecular sieve A4, 50 g of the pseudoboehmite, 5 g of the titanium dioxide, 8 g of the nitric acid solution (5 wt%), 40 g of the sesbania powder, and 30 g of the deionized water were uniformly mixed, and then extruded, dried, and calcined at 480 °C for 12 hours to obtain the support particles;

[0235] The mass ratio of the components was: molecular sieve: alumina: titanium dioxide: acid solution: binder: deionized water = 1:0.5:0.05:0.08:0.4:0.3;

[0236] Step (2): 0.46 g of ammonium hexachloroplatinate was dissolved in a mixture of 40 g of water, 10 g of glycerol and 1.98 g of citric acid monohydrate ligand, and mixed at a temperature of 33 °C for 2 h to obtain a noble metal precursor solution, and the molar ratio of citric acid monohydrate to platinum atoms was 9.09:1;

[0237] Step (3): 100 g of the support particles were immersed in the noble metal precursor solution for 2 h, and after the end of the immersion, they were dried at a temperature of 100 °C for 2 h, and then calcined in an air atmosphere at 600 °C for 12 h to obtain an isodewaxing catalyst, and the loading of noble metal was 0.2 wt%, which was recorded as catalyst C5.

[0238] Example 11

[0239] The present example provides an isodewaxing catalyst, which is prepared by a preparation method comprising the following specific steps:

[0240] Step (1): 100 g of molecular sieve A4, 50 g of pseudoboehmite, 5 g of titanium dioxide, 8 g of nitric acid solution (5 wt%), 40 g of sesbania powder, and 30 g of deionized water were mixed uniformly, extruded, dried, and calcined at 480 °C for 12 hours to obtain support particles;

[0241] The mass ratio of each component is: molecular sieve: alumina: titanium dioxide: acid solution: binder: deionized water = 1:0.5:0.05:0.08:0.4:0.3;

[0242] Step (2): 0.46 g of ammonium hexachloroplatinate was dissolved in a mixture of 40 g of water, 10 g of glycerol and 26 g of hyaluronic acid (Mn≈3500) ligand, and mixed at a temperature of 34 °C for 2 h to obtain a noble metal precursor solution, and the molar ratio of nicotinamide to platinum atoms was 7.17:1;

[0243] Step (3): 100 g of the support particles were immersed in the noble metal precursor solution for 2 h, and after the end of the immersion, they were dried at a temperature of 100 °C for 2 h, and then calcined in an air atmosphere at 500 °C for 12 h to obtain an isodewaxing catalyst, and the loading of noble metal was 0.2 wt%, which was recorded as catalyst C6.

[0244] Comparative Example 7

[0245] The present example provides an isodewaxing catalyst, which is prepared by a preparation method comprising the following specific steps:

[0246] Step (1): 20 g of molecular sieve A6, 100 g of pseudoboehmite, 4 g of titanium dioxide, 6 g of nitric acid solution (5 wt%), 10 g of sesbania powder, and 16 g of deionized water were mixed uniformly, extruded, dried, and calcined at 450 °C for 10 hours to obtain support particles;

[0247] The mass ratio of each component is: molecular sieve: alumina: titanium dioxide: acid solution: binder: deionized water = 1:5:0.2:0.3:0.5:0.8;

[0248] Step (2): 0.42 g of platinum dichloride was dissolved in a mixture of 50 g of water, 2 g of isopropyl alcohol and 1.71 g of lactic acid ligand, and mixed at a temperature of 30°C for 2 h to obtain a noble metal precursor solution, and the molar ratio of lactic acid to platinum atoms was 12:1;

[0249] Step (3): 100 g of the carrier particles were immersed in the noble metal precursor solution for 2 h, and after the immersion was completed, they were dried at a temperature of 100°C for 2 h, and then calcined in an air atmosphere at 450°C for 10 h to obtain an isodewaxing catalyst, and the noble metal loading was 0.3 wt%, which was denoted as catalyst C7.

[0250] Comparative Example 8

[0251] This comparative example provides an isodewaxing catalyst, which is prepared by a preparation method comprising the following specific steps:

[0252] Step (1): 20 g of molecular sieve A7, 100 g of pseudo-boehmite, 4 g of titanium dioxide, 6 g of nitric acid solution (5 wt%), 10 g of sesbania powder, and 16 g of deionized water were mixed uniformly, extruded, dried, and calcined at 450°C for 10 hours to obtain carrier particles;

[0253] The mass ratio of each component is: molecular sieve: alumina: titanium dioxide: acid solution: binder: deionized water = 1:5:0.2:0.3:0.5:0.8;

[0254] Step (2): 0.42 g of platinum dichloride was dissolved in a mixture of 50 g of water, 2 g of isopropyl alcohol and 1.71 g of lactic acid ligand, and mixed at a temperature of 30°C for 2 h to obtain a noble metal precursor solution, and the molar ratio of lactic acid to platinum atoms was 12:1;

[0255] Step (3): 100 g of the carrier particles were immersed in the noble metal precursor solution for 2 h, and after the immersion was completed, they were dried at a temperature of 100°C for 2 h, and then calcined in an air atmosphere at 450°C for 10 h to obtain an isodewaxing catalyst, and the noble metal loading was 0.3 wt%, which was denoted as catalyst C8.

[0256] Comparative Example 9

[0257] This comparative example provides an isodewaxing catalyst, which is prepared by a preparation method comprising the following specific steps:

[0258] Step (1): 20 g molecular sieve A8, 100 g pseudo-boehmite, 4 g titanium dioxide, 6 g nitric acid solution (5 wt%), 10 g sesbania powder, 16 g deionized water were uniformly mixed, extruded, dried, and calcined at 450°C for 10 hours to obtain carrier particles;

[0259] The mass ratio of each component is: molecular sieve: alumina: titanium dioxide: acid solution: binder: deionized water = 1:5:0.2:0.3:0.5:0.8;

[0260] Step (2): 0.42 g of platinum dichloride was dissolved in a mixture of 50 g of water, 2 g of isopropyl alcohol and 1.71 g of lactic acid ligand, and mixed at a temperature of 30°C for 2 hours to obtain a noble metal precursor solution, and the molar ratio of lactic acid to platinum atoms was 12:1;

[0261] Step (3): 100 g of carrier particles were immersed in the noble metal precursor solution for 2 hours, and after the immersion was completed, they were dried at a temperature of 100°C for 2 hours, and then calcined at 450°C for 10 hours in an air atmosphere to obtain an isomerization dewaxing catalyst, and the noble metal loading was 0.3 wt%, which was denoted as catalyst C9.

[0262] Comparative Example 10

[0263] This comparative example provides an isomerization dewaxing catalyst, which is prepared by a preparation method comprising the following specific steps:

[0264] Step (1): 100 g of molecular sieve A3, 20 g of pseudo-boehmite, 4 g of titanium dioxide, 6 g of nitric acid solution (5 wt%), 10 g of sesbania powder, and 16 g of deionized water were uniformly mixed, extruded, dried, and calcined at 450°C for 10 hours to obtain carrier particles;

[0265] The mass ratio of each component is: molecular sieve: alumina: titanium dioxide: acid solution: binder: deionized water = 1:0.2:0.04:0.06:0.1:0.16;

[0266] Step (2): 0.42 g of platinum dichloride was dissolved in a mixture of 50 g of water, 2 g of isopropyl alcohol and 1.71 g of lactic acid ligand, and mixed at a temperature of 30°C for 2 hours to obtain a noble metal precursor solution, and the molar ratio of lactic acid to platinum atoms was 12:1;

[0267] Step (3): 100 g of carrier particles were immersed in the noble metal precursor solution for 2 hours, and after the immersion was completed, they were dried at a temperature of 100°C for 2 hours, and then calcined at 450°C for 10 hours in an air atmosphere to obtain an isomerization dewaxing catalyst, and the noble metal loading was 0.3 wt%, which was denoted as catalyst C10.

[0268] Comparative Example 11

[0269] The comparative example 1 provides an isomerization dewaxing catalyst which is prepared by a preparation method comprising the following specific steps:

[0270] Step (1): 100 g of molecular sieve A10, 30 g of pseudoboehmite, 1 g of titanium dioxide, 1 g of nitric acid solution (5 wt%), 30 g of sesbania powder, and 20 g of deionized water are uniformly mixed, extruded, dried, and calcined at 400 DEG C for 6 hours to obtain carrier particles;

[0271] The mass ratio of each component is: molecular sieve A10: alumina: titanium dioxide: acid solution: binder: deionized water = 1:0.3:0.01:0.01:0.3:0.2;

[0272] Step (2): 1.32 g of chloroplatinic acid hexahydrate is dissolved in a mixture of 25 g of water, 25 g of ethanol, and 1.74 g of sorbic acid ligand, and mixed at a temperature of 30 DEG C for 2 h to obtain a noble metal precursor solution, and the molar ratio of sorbic acid to platinum atoms is 6:1;

[0273] Step (3): 100 g of the carrier particles are immersed in the noble metal precursor solution for 2 h, and after the immersion is completed, the particles are dried at 100 DEG C for 2 h, and then calcined at 400 DEG C in an air atmosphere for 6 hours to obtain an isomerization dewaxing catalyst, and the loading amount of noble metal is 0.5 wt%, which is recorded as catalyst C11.

[0274] The acid data of the catalysts C1-C10 provided by the examples 6-11 and the comparative examples 7-11 of the present application are shown in Table 2.

[0275] Table 2

[0276]

[0277]

[0278] As can be seen from Table 2, the weak B acid (200℃) and the medium strong B acid (350℃) of the isodewaxing catalysts provided by the embodiments 6-11 of the present application are significantly higher than those of the isodewaxing catalysts provided by the comparative examples 7-9 and 11, and the reaction efficiency can be significantly improved when the isodewaxing catalysts are used for the hydrogen isomerization to prepare lubricating oil. For the C11 in the comparative example 11, the weak B acid (200℃) and the medium strong B acid (350℃) of the C11 are lower than those of the C1-C6 due to the fact that the molecular sieve A10 used therein contains ZSM-5 heterocrystals and amorphous silica-alumina. As can be seen from the data of the C1-C6 and C10, although the weak B acid (200℃) and the medium strong B acid (350℃) of the C10 are approximately equivalent to those of the C1-C6, the molecular sieve content of the C10 is higher, so that the acidity is strong, the cracking reaction is more intense when the C10 is used for the hydrogen isomerization to prepare lubricating oil, and the C10 is not suitable for isomerization application, and the catalyst cost is greatly increased.

[0279] Catalyst performance evaluation examples

[0280] In the evaluation examples, the micro-reaction performance of the C1-C11 was evaluated under the reaction conditions that the hydrogenation cracking tail oil was used as the raw material, the reaction temperature was 340℃, the reaction pressure was 16 MPa, the hydrogen to oil ratio was 500:1, the volume space velocity was 1.5h-1, and the reaction time was 1h. -1

[0281] The parameters of the hydrogenation cracking tail oil raw material are shown in Table 3.

[0282] Table 3

[0283]

[0284]

[0285] The evaluation results obtained in the evaluation examples are shown in Table 4.

[0286] Table 4

[0287]

[0288] As can be seen from the above Table 4, the liquid yield, the lubricating oil yield and the heavy viscosity index of the isodewaxing catalysts provided by the embodiments 6-11 of the present application are obviously higher than those of the isodewaxing catalysts provided by the comparative examples 7-11, and the heavy base oil pour point and the heavy base oil cloud point are obviously lower than those of the isodewaxing catalysts provided by the comparative examples 7-11, which indicates that the isodewaxing catalysts provided by the embodiments of the present application have higher reaction efficiency and isomerization conversion rate, and lower cracking rate.

[0289] As can be seen from the above, compared with the prior art, the embodiments of the present application can achieve the following beneficial technical effects:​

[0290] 1) The embodiment of the present application uses a crystallization inducer in the preparation of ZSM-48 molecular sieve, which can induce more crystal nuclei to form rapidly, greatly shorten the crystallization time, reduce the crystal size, i.e. form more small crystal molecular sieves, and the length of the crystal is only 0.1-0.5 μm. When the isomerization dewaxing catalyst (the carrier particles of which contain the above-mentioned ZSM-48 molecular sieve) is used for the preparation of lubricating oil by hydroisomerization, it is beneficial for the product to diffuse out of the pore, thereby the cracking reaction can be reduced;

[0291] 2) The embodiment of the present application uses an alcohol as a charge balancing agent in the preparation of ZSM-48 molecular sieve. The alcohol is dissolved in water, and the molecular size is between that of water molecules and the structure directing agent (i.e. template, including the first template and the second template), which can enter the pore. In the process of molecular sieve synthesis, it can replace part of the water molecules to play the role of supporting / filling the pore. The hydroxyl group contained in the alcohol forms a hydrogen bond with the inorganic anion framework of the molecular sieve, maintains the charge balance in the pore, and makes more water molecules in the system play the role of solvent (equivalent to the increase of the water phase), thereby the fluidity is enhanced, the crystal grains are uniformly dispersed in the solvent, and it is easier to form small crystal molecular sieves, i.e. it is beneficial for the formation of small crystal. In addition, the alcohol as a charge balancing agent does not change the pH value of the system, thereby the generation of impurities can be avoided, and the added charge balancing agent is also beneficial for the uniform distribution of the acid sites of the molecular sieve. When the isomerization dewaxing catalyst (the carrier particles of which contain the above-mentioned ZSM-48 molecular sieve) is used for the preparation of lubricating oil by hydroisomerization, the reaction efficiency can be improved;

[0292] 3) The embodiment of the present application uses a pore-forming agent in the preparation of ZSM-48 molecular sieve. During the synthesis of the molecular sieve, mesopores and micropores can be directly formed. When the isomerization dewaxing catalyst (the carrier particles of which contain the above-mentioned ZSM-48 molecular sieve) is used for the preparation of lubricating oil by hydroisomerization, it is beneficial for the diffusion of the reactants and products in the pore, i.e. the diffusion efficiency of the reactants and products can be improved, the reaction efficiency, isomerization conversion rate, and cracking rate can be reduced, and the amount of the molecular sieve in the catalyst can be reduced;

[0293] 4) In the preparation of ZSM-48 molecular sieve, the gel solution is pre-crystallized at 70-90 ℃ for 2-6 h, crystallized at 120-140 ℃ for 2-6 h, and crystallized at 140-170 ℃ for 10-48 h. The first-stage crystallization forms a primary structure, and the second-stage crystallization forms more crystal nuclei, which is beneficial for the rapid growth of small crystal at the third-stage crystallization temperature. The small crystal molecular sieve has a short pore length, which is beneficial for the rapid diffusion of the reaction product out of the pore and the reduction of the secondary cracking reaction;

[0294] 5) The preparation method of the embodiment of the present application can directly synthesize short-axis ZSM-zeolite, shorten the channel length, and when an isomerization dewaxing catalyst (the carrier particles of which contain the above-mentioned ZSM-48 zeolite) is used for the preparation of lubricating oil by hydroisomerization, the reaction efficiency can be significantly improved.

[0295] The above is only a specific embodiment of the present application, which cannot limit the scope of the implementation of the application, so the replacement of equivalent components or equivalent changes and modifications made within the scope of the patent protection of the present application should still belong to the scope covered by the present patent. In addition, the technical features in the present application can be freely combined with each other, between technical features, between technical features and technical inventions, and between technical inventions.

Claims

1. A method for preparing ZSM-48 molecular sieve, characterized in that, The preparation method of the ZSM-48 molecular sieve includes: Step 1: Mix the aluminum source, silicon source, alkali source, crystallization inducer, template agent, deionized water, pore-forming agent and charge balancing agent evenly to obtain a gel solution; Among them, the aluminum source is calculated as Al2O3, and the aluminum source is calculated as OH. - The molar ratio of the alkali source, template agent, H2O and silicon source (calculated as SiO2) is 0.0025-0.02:0.006-0.38:0.11-1.5:10-50:1; The molar ratio of the pore-forming agent to the silicon source (calculated as SiO2) is 0.01-0.2:1; The molar ratio of crystallization inducer (calculated as M2O) to silicon source (calculated as SiO2) is 0.002-0.2:1, wherein M is one or more alkali metals; The molar ratio of the charge balancing agent to H2O is 0.1-1:1, and the charge balancing agent includes one or a combination of several of glycerol, ethylene glycol, isopropanol, propanol, and 2-butanol. Step 2: Pre-crystallize the gel solution at 70-90℃ for 2-6 hours, crystallize at 120-140℃ for 2-6 hours, and crystallize at 140-170℃ for 10-48 hours to obtain the crystallized product. Step 3: Wash, dry and calcine the crystallized product to obtain the molecular sieve precursor; Step 4: The molecular sieve precursor is mixed with ammonium salt, and then washed, dried and calcined to obtain the ZSM-48 molecular sieve.

2. The preparation method according to claim 1, characterized in that, The aluminum source includes one or a combination of aluminum sulfate, sodium aluminate, and aluminum nitrate. The silicon source includes one or a combination of several of silica sol, silica fume, and tetraethyl orthosilicate. The alkali source includes NaOH and / or KOH.

3. The preparation method according to claim 1, characterized in that, The template agent includes a first template agent and a second template agent, and the molar ratio of the first template agent and the second template agent is 1-400:

1.

4. The preparation method according to claim 3, characterized in that, The first template agent includes one or a combination of several of cyclohexylamine, dodecylamine, 1,6-hexanediamine, 1,8-octanediamine and benzylamine, and the second template agent includes one or a combination of several of hexamethylammonium chloride, hexamethyldiammonium bromide, ammonium oxalate, ammonium acetate and benzyltriethylammonium bromide.

5. The preparation method according to claim 1, characterized in that, The ammonium salt includes one or a combination of several of ammonium chloride, ammonium nitrate and ammonium sulfate.

6. The preparation method according to any one of claims 1-5, characterized in that, The crystallization inducing agent includes one or a combination of several of sodium chloride, potassium chloride, sodium sulfate, and potassium sulfate.

7. The preparation method according to any one of claims 1-5, characterized in that, The pore-forming agent includes one or a combination of several of P123, Triton-100, polyhexamethylene biguanide, ammonium chloride, and polyvinyl alcohol.

8. A ZSM-48 molecular sieve, characterized in that, The ZSM-48 molecular sieve is prepared by the method described in any one of claims 1-7.

9. The ZSM-48 molecular sieve according to claim 8, characterized in that, The ZSM-48 molecular sieve has a grain length of 0.1-0.5 μm, a grain diameter of 50-100 nm, and an axis-to-diameter ratio of 2-10.

10. An isomerization dewaxing catalyst, comprising support particles and a noble metal active component supported on the support particles, characterized in that, The carrier particles comprise the ZSM-48 molecular sieve as described in claim 8 or 9, and the loading of the noble metal active component is 0.1-0.5 wt% of the carrier particle mass.

11. The isomerization dewaxing catalyst according to claim 10, characterized in that, The noble metal active component includes platinum and / or palladium.

12. The isomerization dewaxing catalyst according to claim 10 or 11, characterized in that, The carrier particles are prepared by uniformly mixing ZSM-48 molecular sieve, alumina, titanium dioxide, acid solution, binder, and deionized water, followed by extrusion, drying, and calcination. The mass ratio of ZSM-48 molecular sieve, alumina, titanium dioxide, acid solution, binder, and deionized water is 1:0.3-9:0.01-0.5:0.01-0.6:0.3-1:0.2-1.

13. The isomerization dewaxing catalyst according to claim 12, characterized in that, The adhesive comprises guar gum powder and / or methylcellulose; the acid solution comprises a nitric acid or phosphoric acid solution with a concentration of 5-15 wt%.

14. A method for preparing the isomerization dewaxing catalyst according to any one of claims 10-13, characterized in that, The preparation method includes: Step (1): Dissolve the noble metal salt in a mixture of water, alcohol and ligand and mix thoroughly to obtain a noble metal precursor solution; Step (2): The carrier particles are impregnated in a noble metal precursor solution, and then the impregnated product is dried and calcined to obtain the isomer dewaxing catalyst.

15. The preparation method according to claim 14, characterized in that, The precious metal salt includes one or a combination of several of the following: chloroplatinic acid hexahydrate, palladium chloride, platinum dichloride, and ammonium hexachloroplatinate.

16. The preparation method according to claim 14 or 15, characterized in that, The ligands include one or more of sorbic acid, salicylic acid, nicotinamide, lactic acid, citric acid, and hyaluronic acid, and the molar ratio of the ligand to the noble metal atom is 6-18:

1.

17. The preparation method according to claim 14 or 15, characterized in that, The alcohols include one or a combination of several of ethanol, propanol, isopropanol, and glycerol, and the mass ratio of water to alcohols is 50-1:

1.

18. The preparation method according to claim 14 or 15, characterized in that, In step (2), the calcination is carried out in an air atmosphere at 450-600℃ for 4-14 hours.

19. The use of the isomerization dewaxing catalyst according to any one of claims 10-13 in the preparation of lubricating oil by hydroisomerization of heavy feedstock.

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