Naphtha reforming catalyst, preparation method and application thereof, and method for naphtha catalytic reforming

Abstract

The present application relates to the technical field of coal chemical industry, in particular to a naphtha reforming catalyst, a preparation method and application thereof, and a naphtha catalytic reforming method. The catalyst comprises a carrier and an active component loaded on the carrier, wherein the carrier comprises KL type molecular sieve, and the content of oxide binder in the carrier is not higher than 5 wt%; the active component comprises Group VIII metal element and rare earth element. The catalyst of the present application adopts the carrier containing KL type molecular sieve and the carrier in which the content of oxide binder is not higher than 5 wt%, and loads the active component containing Group VIII metal element and rare earth element, and has high aromatic yield and stability in the process of naphtha catalytic reforming.

Description

Technical Field

[0001] This invention relates to the field of coal chemical technology, specifically to a naphtha reforming catalyst, its preparation method and application, and a method for naphtha catalytic reforming. Background Technology

[0002] Aromatic hydrocarbons are fundamental raw materials in the chemical industry, widely used in the synthesis of resins, synthetic fibers, synthetic rubber, synthetic detergents, plasticizers, dyes, pharmaceuticals, fragrances, pesticides, and specialty chemicals. They are also a crucial component of high-octane gasoline, playing a vital role in developing the national economy and improving people's lives. Petroleum is the main source of aromatic hydrocarbon products, with the production of BTX and other products from naphtha through catalytic reforming being one of the primary sources.

[0003] Coal indirect liquefaction is the process of producing liquid oil products from coal. Coal-based naphtha products based on Fischer-Tropsch synthesis can replace petroleum-based naphtha in some fields, thus playing a positive role in adjusting the energy structure and ensuring energy security. Fischer-Tropsch synthetic naphtha mainly consists of normal and isoalkanes, with low contents of cycloalkanes and aromatics. However, the conversion rate and selectivity of alkane dehydrogenation cyclization reactions in traditional catalytic reforming reactions based on Pt / Al₂O₃ catalysts are both low. Therefore, Fischer-Tropsch synthetic naphtha is not suitable as a feedstock for catalytic reforming in the production of aromatics and high-octane gasoline components. This is a problem that needs to be solved for the industrial application of Fischer-Tropsch synthetic naphtha.

[0004] CN107573966B discloses a method for producing high-octane gasoline components from Fischer-Tropsch naphtha. The method uses ZSM-5 zeolite and alumina as supports, and prepares a catalyst with Group VA oxides and rare earth oxides as active components. This catalyst enables a series of reactions in the Fischer-Tropsch feedstock, including alkylation, hydrogen transfer, aromatization, alkylation, and isomerization, thereby generating high-octane gasoline products. This technology achieves an aromatic yield of approximately 35 wt% and is primarily suitable for the production of high-octane gasoline components.

[0005] CN114653395A discloses a method for processing Fischer-Tropsch naphtha with a high alkane content into high-octane gasoline or aromatic products. The method involves mixing alumina and potassium-containing molecular sieve materials as a catalyst support, and then loading platinum to prepare a catalyst that catalyzes the reforming reaction of Fischer-Tropsch naphtha, thereby achieving a high aromatic yield. This technology currently yields approximately 55-60 wt% aromatics from Fischer-Tropsch naphtha feedstock, indicating room for further improvement. Summary of the Invention

[0006] The purpose of this invention is to overcome the problem of low aromatic yield in the Fischer-Tropsch naphtha reforming reaction in the prior art, and to provide a naphtha reforming catalyst, its preparation method and application, and a method for naphtha catalytic reforming. This catalyst has the characteristics of high aromatic yield and good stability.

[0007] To achieve the above objectives, the first aspect of the present invention provides a naphtha reforming catalyst, the catalyst comprising a support and an active component supported on the support, wherein the support comprises a KL-type molecular sieve, and the oxide binder content in the support is not higher than 5 wt%; the active component comprises a Group VIII metal element and a rare earth element.

[0008] The second aspect of the present invention provides a method for preparing the catalyst described in the first aspect, the method comprising the following steps: S1, contacting a solution containing rare earth elements, group VIII metal elements and optionally halogens with a support to obtain a catalyst precursor; S2, drying, calcining and reducing the catalyst precursor.

[0009] The third aspect of this invention provides the application of the catalyst described in the first aspect and / or the catalyst prepared by the preparation method described in the second aspect in naphtha catalytic reforming.

[0010] A fourth aspect of the present invention provides a method for catalytic reforming of naphtha, the method comprising: reacting naphtha with hydrogen under catalytic conditions; wherein the catalyst is the catalyst described in the first aspect and / or the catalyst prepared by the preparation method described in the second aspect.

[0011] Through the above technical solution, the present invention has the following advantages:

[0012] The catalyst of the present invention uses a support containing KL-type molecular sieves and an oxide binder content of no more than 5 wt% to support active components containing Group VIII metal elements and rare earth elements, and exhibits high aromatic hydrocarbon yield and stability in naphtha catalytic reforming. Attached Figure Description

[0013] Figure 1 SEM image of the carrier ZT-1 prepared in Example 1;

[0014] Figure 2 The image shows the XRD pattern of the carrier ZT-1 prepared in Example 1. Detailed Implementation

[0015] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0016] In this invention, "KL-type molecular sieve" refers to an L-type molecular sieve with an alkali metal element content of 8 wt% or more.

[0017] This invention provides a naphtha reforming catalyst, which includes a support and an active component supported on the support. The support includes a KL-type molecular sieve, and the oxide binder content in the support is not higher than 5 wt%. The active component includes Group VIII metal elements and rare earth elements.

[0018] The catalyst of the present invention uses a support containing KL-type molecular sieves and an oxide binder content of no more than 5 wt% to support active components containing Group VIII metal elements and rare earth elements, and exhibits high aromatic hydrocarbon yield and stability in naphtha catalytic reforming.

[0019] According to a preferred embodiment of the present invention, the content of the active component in the catalyst, calculated as an element, is 0.5-10 wt% based on the total weight of the catalyst.

[0020] According to a preferred embodiment of the present invention, the oxide binder content in the carrier can achieve the objective of the present invention as long as it is within the aforementioned range, for example, not higher than 4.5wt%, 4wt%, 3.5wt%, 3wt%, 2.5wt%, 2wt%, 1.5wt%, 1wt%, 0.5wt%, and 0.1wt%, preferably not higher than 1.0wt%. By adopting the aforementioned preferred embodiment, the high aromatic yield and stability of the catalyst in the naphtha catalytic reforming process can be further improved.

[0021] According to a preferred embodiment of the present invention, the oxide binder includes at least one of aluminum oxide, silicon oxide and calcium oxide, preferably aluminum oxide.

[0022] According to a preferred embodiment of the present invention, the active component further includes a halogen. By adopting the aforementioned preferred embodiment, the yield and stability of high aromatic hydrocarbons in the naphtha catalytic reforming process can be further improved.

[0023] To further improve the yield and stability of high aromatic hydrocarbons in the naphtha catalytic reforming process, according to a preferred embodiment of the present invention, the halogen content in the catalyst, based on the total weight of the catalyst, is 0.5-1.5 wt%, for example, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1.1 wt%, 1.2 wt%, 1.3 wt%, and 1.4 wt%, preferably 0.5-1 wt%.

[0024] In this invention, as long as the purpose of this invention can be achieved, there are no special requirements for the type of halogen element. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the halogen is selected from at least one of F, Cl, Br and I, preferably F and / or Cl.

[0025] To further improve the yield and stability of high aromatic hydrocarbons in the naphtha catalytic reforming process, according to a preferred embodiment of the present invention, the weight ratio of Group VIII metal elements to halogens in the catalyst is 1:(0.3-3), for example, it can be 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1.2, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2, 1:2.3, 1:2.6, and 1:2.9, preferably 1:(0.8-2).

[0026] According to a preferred embodiment of the present invention, the content of alkali metal elements in the KL-type molecular sieve is 8-20 wt%, for example, it can be 9 wt%, 10 wt%, 11 wt%, 13 wt%, 15 wt%, 17 wt%, and 19 wt%, preferably 12-20 wt%. By adopting the aforementioned preferred embodiment, the high aromatic yield and stability of the catalyst in the naphtha catalytic reforming process can be further improved.

[0027] In this invention, as long as the purpose of this invention can be achieved, there are no special requirements for the type of alkali metal. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the alkali metal element includes K and optionally at least one of Na, Rb and Cs, preferably K.

[0028] According to a preferred embodiment of the present invention, the molar ratio of SiO2 to Al2O3 in the KL-type molecular sieve is 2.5-3.5, for example, it can be 2.6, 2.8, 2.9, 3.1, 3.2, 3.3 and 3.4, preferably 2.7-3. By adopting the aforementioned preferred embodiment, the high aromatic hydrocarbon yield and stability of the catalyst in the naphtha catalytic reforming process can be further improved.

[0029] According to a preferred embodiment of the present invention, the relative crystallinity of the KL-type molecular sieve is 90-100%, preferably 95-100%.

[0030] According to a preferred embodiment of the present invention, the average particle size of the KL-type molecular sieve is 300-2000 nm, preferably 500-1000 nm.

[0031] According to a preferred embodiment of the present invention, based on the total weight of the catalyst, the content of the Group VIII metal element is 0.2-1.5 wt%, for example, 0.3 wt%, 0.4 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1.1 wt%, 1.2 wt%, 1.3 wt%, and 1.4 wt%, preferably 0.5-1 wt%.

[0032] According to a preferred embodiment of the present invention, based on the total weight of the catalyst, the content of the rare earth elements is 0.1-3 wt%, for example, 0.2 wt%, 0.4 wt%, 0.5 wt%, 0.7 wt%, 0.9 wt%, 1.2 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, and 2.8 wt%, preferably 0.1-1 wt%. By adopting the aforementioned preferred embodiment, the yield and stability of high aromatic hydrocarbons in the naphtha catalytic reforming process can be further improved.

[0033] To further improve the yield and stability of high aromatic hydrocarbons in the naphtha catalytic reforming process, according to a preferred embodiment of the present invention, the weight ratio of Group VIII metal elements to rare earth elements in the catalyst is 1:(0.1-6), for example, it can be 1:0.2, 1:0.5, 1:1.5, 1:2.5, 1:3.5, 1:4, 1:4.5, 1:5 and 1:5.5, preferably 1:(0.1-2).

[0034] In this invention, the group VIII metal element is a conventionally chosen element. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the group VIII metal element is selected from at least one of Pt, Ru and Rh, preferably Pt.

[0035] In this invention, the rare earth elements are conventionally selected. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the rare earth elements are selected from at least one of La, Ce and Pr, preferably La and / or Ce.

[0036] Catalyst products that meet the foregoing requirements of this invention can achieve the purpose of this invention. There are no special requirements for their preparation methods. The following is an illustrative description, but it does not limit the scope of this invention. This invention provides a method for preparing the catalyst described above. The preparation method includes the following steps: S1, contacting a solution containing rare earth elements, group VIII metal elements and optionally halogens with a support to obtain a catalyst precursor; S2, drying, calcining and reducing the catalyst precursor.

[0037] Any carrier that meets the foregoing requirements of this invention can achieve the purpose of this invention. There are no special requirements for the preparation method of the carrier. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the preparation method of the KL-type molecular sieve includes the following steps: I. Mixing silicon source, aluminum source, alkali source and water to obtain a mixture gel; II. Performing hydrothermal crystallization treatment on the mixture gel and then separating the solid and liquid, washing, drying and shaping the solid product.

[0038] In this invention, step I includes: adding an aluminum source and an alkali source to water for a first dynamic mixing to obtain an aluminum sol, and adding a silicon source to the aluminum sol for a second dynamic mixing to obtain a mixture gel.

[0039] In this invention, as long as the purpose of this invention can be achieved, there are no special requirements for the type of silicon source. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the silicon source is selected from at least one of silica sol, silicon dioxide and silicic acid, preferably silica sol, and more preferably silica sol with a SiO2 content of 20-45 wt%.

[0040] In this invention, the aluminum source is a conventional choice in the art. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the aluminum source is aluminum hydroxide and / or sodium aluminate.

[0041] In this invention, the alkali source is an inorganic alkali, which is selected from at least one of sodium hydroxide, potassium hydroxide, rubidium hydroxide and cesium hydroxide, preferably sodium hydroxide and / or potassium hydroxide.

[0042] In this invention, as long as the purpose of this invention can be achieved, there are no special requirements for the conditions of the first dynamic mixing and the conditions of the second dynamic mixing. The conditions of the first dynamic mixing and the conditions of the second dynamic mixing each independently include: the temperature is 20-100℃, and the time is adjusted accordingly with the change of temperature to ensure that the mixing is sufficient.

[0043] In this invention, the conditions for the hydrothermal crystallization treatment can be conventional choices in the art. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the conditions for the hydrothermal crystallization treatment include: a temperature of 150-200°C, and the time is adjusted accordingly with the temperature to ensure that the hydrothermal crystallization treatment is sufficient, for example, a time of 24-96 hours.

[0044] In this invention, cooling is performed before solid-liquid separation. The cooling temperature is a conventional choice in the field and will not be described in detail here. This invention uses cooling to 40°C as an example to illustrate the advantages of this invention.

[0045] In this invention, the washing method is a conventional method in the art, and will not be described in detail. The following is an illustrative description, in which the washing method includes washing with deionized water until the pH value is 7-8.

[0046] In this invention, the drying conditions in step II are conventional choices in the field and will not be described in detail. This invention uses a drying temperature of 120°C and a drying time of 10 hours as an example to illustrate the advantages of this invention.

[0047] In this invention, the molding method is a conventional choice in the art. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the molding method is tableting, and the tableting conditions include a pressure of 8-25 MPa.

[0048] In this invention, as long as the purpose of this invention can be achieved, there are no special requirements for the method of obtaining the catalyst precursor. The method of obtaining the catalyst precursor can be one-step contact or step-by-step contact. According to a preferred embodiment of this invention, the method of obtaining the catalyst precursor includes: (1) contacting a solution containing rare earth elements with a support, drying and calcining to obtain a support containing rare earth elements; (2) contacting a solution containing Group VIII metal elements and optionally halogens with a support containing rare earth elements to obtain the catalyst precursor.

[0049] In this invention, the ratio of rare earth element content to carrier content during contact in step (1) has a wide selectable range. Commonly used ratio ranges can achieve the purpose of this invention. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the ratio of rare earth element content to carrier content during contact in step (1) is 0.1-3%:50, for example, it can be 0.2%:50, 0.4%:50, 0.5%:50, 0.6%:50, 0.8%:50, 1%:50, 1.2%:50, 1.5%:50, 1.8%:50, 2%:50, 2.3%:50, 2.5%:50, 2.7%:50 and 2.9%:50, preferably 0.1-1%:50.

[0050] In this invention, the ratio of the amount of Group VIII metal element to the amount of carrier during contact in step (2) has a wide selectable range. Commonly used ratio ranges can achieve the purpose of this invention. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the ratio of the amount of Group VIII metal element to the amount of carrier during contact in step (2) is 0.2-1.5%:50, for example, it can be 0.3%:50, 0.4%:50, 0.5%:50, 0.6%:50, 0.8%:50, 1%:50, 1.2%:50, 1.3%:50 and 1.4%:50, preferably 0.5-1%:50.

[0051] In this invention, the ratio of halogen to carrier during contact in step (2) has a wide selectable range. Commonly used ratio ranges can achieve the purpose of this invention. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the ratio of halogen to carrier during contact in step (2) is 0.5-1.5%:50, for example, it can be 0.6%:50, 0.8%:50, 1%:50, 1.2%:50, 1.3%:50 and 1.4%:50, preferably 0.5-1%:50.

[0052] In this invention, the source of the rare earth element is a conventional choice in the art. The following is an illustrative description, but does not limit the scope of the invention. According to a preferred embodiment of the invention, the rare earth element is derived from a rare earth soluble compound, preferably a rare earth nitrate, such as at least one of cerium nitrate, lanthanum nitrate, and praseodymium nitrate.

[0053] In this invention, as long as the purpose of this invention can be achieved, there are no special requirements on the source of the Group VIII metal element. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the Group VIII metal element is derived from a Group VIII metal compound. The Group VIII metal compound is a Group VIII metal soluble compound, preferably selected from at least one of chloroplatinic acid, tetraammonium dichloroplatinate, ammonium chloroplatinate, platinum trichloride, platinum tetrachloride hydrate, dicarbonyl platinum dichloride, dinitrodiaminoplatinum, and sodium tetranitroplatinate, more preferably chloroplatinic acid.

[0054] In this invention, as long as the purpose of this invention can be achieved, there are no special requirements for the source of the halogen. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the halogen is derived from a non-Group VIII metal halide, which is a halogen-containing acid and / or salt, such as at least one of hydrochloric acid, hydrofluoric acid, potassium chloride, potassium fluoride, sodium chloride, and sodium fluoride.

[0055] In this invention, the liquid-to-solid volume ratio during contact in steps (1) and (2) is a conventional choice in the art. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the liquid-to-solid volume ratio during contact in steps (1) and (2) is 1.0-2.0.

[0056] In this invention, the contact conditions in steps (1) and (2) are conventional choices in the art. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the contact conditions in steps (1) and (2) each independently include: a temperature of 20-80°C, a time of 3-12h, a pressure of 0.01-0.5MPa, and a rotation speed of 0.01-0.20m / s.

[0057] In this invention, as long as the purpose of this invention can be achieved, the drying conditions in steps (1) and (2) are not particularly required. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the drying conditions in steps (1) and (2) each independently include: a temperature of 70-150°C, and the drying time is adjusted accordingly with the drying temperature to ensure sufficient drying, for example, a time of 3-48 hours.

[0058] In this invention, the roasting conditions in steps (1) and S2 are conventional choices in the art. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the roasting conditions in steps (1) and S2 each independently include: a temperature of 300-550°C, and the roasting time can be adjusted accordingly with the change of roasting temperature, for example, a time of 2-12 hours.

[0059] In this invention, according to a preferred embodiment, the gas / agent volume ratio during calcination in steps (1) and (S2) is 500-1000.

[0060] In this invention, the reduction conditions are conventional choices in the art. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the reduction conditions include: a temperature of 400-520°C, and the reduction time is adjusted accordingly with the reduction temperature to ensure sufficient reduction, for example, a time of 2-12 hours.

[0061] In this invention, the range of selectable gas / agent volume ratio for reduction is relatively wide. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the gas / agent volume ratio for reduction is 300-1500.

[0062] This invention provides the application of the catalyst described herein and / or the catalyst prepared by the preparation method described herein in naphtha catalytic reforming.

[0063] This invention provides a method for catalytic reforming of naphtha, the method comprising: reacting naphtha with hydrogen under catalytic conditions; wherein the catalyst is the catalyst described above and / or the catalyst prepared by the preparation method described above.

[0064] In this invention, the source of the naphtha is not limited. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the naphtha is Fischer-Tropsch synthetic naphtha. Preferably, the total mass fraction of n-alkanes and isoalkanes in the Fischer-Tropsch synthetic naphtha is ≥70%, and more preferably, the total mass fraction of n-alkanes and isoalkanes in the Fischer-Tropsch synthetic naphtha is ≥90%.

[0065] According to a preferred embodiment of the present invention, the conditions for the contact reaction include a temperature of 420-520°C, preferably 450-500°C.

[0066] According to a preferred embodiment of the present invention, the conditions for the contact reaction include a pressure of 0.3-1.2 MPa, preferably 0.3-1.2 MPa.

[0067] According to a preferred embodiment of the present invention, the conditions for the contact reaction include: a naphtha feed mass hourly space velocity of 1-4 h⁻¹. -1 Preferably 1.5-2.5h -1 .

[0068] According to a preferred embodiment of the present invention, the conditions for the contact reaction include a hydrogen / hydrocarbon volume ratio of 600-1800, preferably 600-1200.

[0069] The present invention will be described in detail below through embodiments. In the following embodiments,

[0070] The chemical composition was determined using a Rigaku Electric Co., Ltd. 3013 X-ray fluorescence spectrometer, and the silicon-to-aluminum ratio was calculated. The tungsten target was used, the excitation voltage was 40 kV, and the excitation current was 50 mA.

[0071] The specific surface area and pore volume of the molecular sieve and catalyst were calculated using a BET testing system. The instrument was an ASAP2400 specific surface area analyzer manufactured by Micromeritics Instruments. The specific surface area of ​​the sample was calculated using the BET (Brunauer-Emmett-Teller) equation. The volume of N2 adsorbed by the sample at a relative pressure (p / p0) of 0.98 was measured and converted to liquid nitrogen volume, which is the total pore volume.

[0072] The microstructure of the molecular sieves and catalysts was analyzed using scanning electron microscopy (SEM).

[0073] The crystal phase and relative crystallinity of the molecular sieve were analyzed by X-ray powder diffraction. The analysis conditions were: Cu target, Kα radiation, Ni filter, tube voltage 45kV, tube current 250mA, scanning range 0.5°-50°, and step width 0.02°. The relative crystallinity was calculated as follows: the peak areas of the characteristic peaks at 2θ angles of 14.7, 19.3, 22.6, 24.3, 25.5, 28.0, 29.0, and 30.6 in the XRD pattern of the tested molecular sieve were summed and denoted as A. The sum of the peak areas of the above characteristic peaks in the XRD pattern of the standard sample was denoted as B. The ratio of A to B is the relative crystallinity of the tested L molecular sieve.

[0074] The composition of the reaction products was determined and the yield was calculated using gas chromatography. An Agilent 7697B gas chromatograph equipped with a flame ionization detector (FID) and a capillary column (CBP-W12-100) was used for the test.

[0075] Unless otherwise specified, all raw materials are commercially available products.

[0076] Example 1

[0077] KL-type molecular sieves were prepared using the following steps:

[0078] (1) Dissolve Al(OH)3 (aluminum source, mass fraction of 99%) and KOH (alkali source, mass fraction of 95%) in deionized water and heat to 90℃ to dissolve and obtain aluminum sol; add aluminum sol to silica sol (silicon source, mass fraction of 25.6%, calculated as SiO2) under stirring and stir for 0.5h to obtain a mixture gel;

[0079] (2) The mixture gel was transferred into a reactor and subjected to hydrothermal crystallization at 170°C for 72 hours, then cooled to 40°C. The product was separated into solid and mother liquor. The solid was washed with deionized water until the pH of the washing solution was 8, and then dried at 120°C for 10 hours to obtain molecular sieve powder. The powder was pressed into tablets at a pressure of 20 MPa to obtain KL-type molecular sieve, denoted as ZT-1. TEM and XRD tests were performed on KL-type molecular sieve ZT-1, and the test results are as follows: Figure 1 and Figure 2 As shown, from Figure 1 It can be seen from this that the molecular sieve crystals are regular, with a crystal size of 0.6 μm. Figure 2 As can be seen from the XRD pattern, the characteristic peaks of the KL molecular sieve crystal form are obvious, and there are no characteristic peaks of other crystal forms such as W impurities, indicating that the molecular sieve has good crystallinity. The structure of KL type molecular sieve ZT-1 is shown in Table 1.

[0080] The catalyst was prepared using the following steps:

[0081] S1. Take 50g of the ZT-1 prepared above as a carrier, and prepare an impregnation solution with cerium nitrate, so that the content of cerium nitrate in the impregnation solution, calculated as Ce, is 0.5% by weight (relative to the weight of the KL type molecular sieve). Pour ZT-1 and the impregnation solution into a 500mL flask (the liquid / solid volume ratio of the impregnation solution to ZT-1 is 1.5), and impregnate in a rotary vacuum evaporator at 25℃, 0.02MPa, and a rotational speed of 0.03m / s for 3h. Dry the solid under reduced pressure at 70℃, dry at 120℃ for 12h, and calcine in dry air at 350℃ and a gas / agent volume ratio of 700 for 4h to obtain a KL type molecular sieve containing Ce, denoted as ZT-1-Ce.

[0082] S2. Prepare an impregnation solution by mixing chloroplatinic acid and potassium chloride, such that the content of chloroplatinic acid (calculated as Pt) in the impregnation solution is 1.0 wt% and the content of potassium chloride (calculated as Cl) is 1.0 wt% (both relative to the weight of KL type molecular sieve). Pour ZT-1-Ce and the impregnation solution into a 500 mL flask (the liquid / solid volume ratio of the impregnation solution to ZT-1 is 1.5), and impregnate in a rotary vacuum evaporator at 25 °C, 0.02 MPa, and a rotational speed of 0.03 m / s for 3 h. Dry the solid under reduced pressure at 70 °C, dry at 120 °C for 12 h, calcine in dry air at 350 °C and a gas / agent volume ratio of 700 for 4 h, and then reduce with H2 at 480 °C and a gas / agent volume ratio of 500 for 4 h to obtain catalyst Cat-1, the composition of which is shown in Table 2.

[0083] Example 2

[0084] KL-type molecular sieves were prepared using the following steps:

[0085] (1) Dissolve Al(OH)3 (aluminum source, mass fraction of 99%) and KOH (alkali source, mass fraction of 95%) in deionized water and heat to 90℃ to dissolve and obtain aluminum sol; add aluminum sol to silica sol (silicon source, mass fraction of 25.6%, calculated as SiO2) under stirring and stir for 0.5h to obtain a mixture gel;

[0086] (2) The mixture gel was transferred into a reactor and subjected to hydrothermal crystallization at 170°C for 72 hours, then cooled to 40°C. The product was separated into solid and mother liquor. The solid was washed with deionized water until the pH of the washing liquid was 8, and then dried at 120°C for 10 hours to obtain molecular sieve powder. The powder was pressed into tablets at a pressure of 20 MPa to obtain KL-type molecular sieve, denoted as ZT-2. TEM and XRD tests were performed on KL-type molecular sieve ZT-2. The test results were consistent with... Figure 1 and Figure 2 Similarly, the structure of KL-type molecular sieve ZT-2 is shown in Table 1.

[0087] The catalyst was prepared using the following steps:

[0088] S1. Take 50g of the ZT-2 prepared above as a carrier, and prepare an impregnation solution with cerium nitrate, so that the content of cerium nitrate in the impregnation solution, calculated as Ce, is 0.2% by weight (relative to the weight of the KL type molecular sieve). Pour ZT-2 and the impregnation solution into a 500mL flask (the liquid / solid volume ratio of the impregnation solution to ZT-2 is 1.5), and impregnate in a rotary vacuum evaporator at 25℃, 0.02MPa, and a rotational speed of 0.03m / s for 3h. Dry the solid under reduced pressure at 70℃, dry at 120℃ for 12h, and calcine in dry air at 350℃ and a gas / agent volume ratio of 700 for 4h to obtain a KL type molecular sieve containing Ce, denoted as ZT-2-Ce.

[0089] S2. Prepare an impregnation solution by mixing chloroplatinic acid and potassium chloride, such that the content of chloroplatinic acid (calculated as Pt) in the impregnation solution is 0.6% by weight and the content of potassium chloride (calculated as Cl) is 0.5% by weight (both relative to the weight of KL type molecular sieve). Pour ZT-2-Ce and the impregnation solution into a 500 mL flask (the liquid / solid volume ratio of the impregnation solution to ZT-2 is 1.5), and impregnate in a rotary vacuum evaporator at 25 °C, 0.02 MPa, and a rotational speed of 0.03 m / s for 3 h. Dry the solid under reduced pressure at 70 °C, dry at 120 °C for 12 h, calcine in dry air at 350 °C and a gas / agent volume ratio of 700 for 4 h, and then reduce with H2 at 480 °C and a gas / agent volume ratio of 500 for 4 h to obtain catalyst Cat-2, the composition of which is shown in Table 2.

[0090] Example 3

[0091] KL-type molecular sieves were prepared using the following steps:

[0092] (1) Dissolve Al(OH)3 (aluminum source, mass fraction of 99%) and KOH (alkali source, mass fraction of 95%) in deionized water and heat to 90℃ to dissolve and obtain aluminum sol; add aluminum sol to silica sol (silicon source, mass fraction of 25.6%, calculated as SiO2) under stirring and stir for 0.5h to obtain a mixture gel;

[0093] (2) The mixture gel was transferred into a reactor and subjected to hydrothermal crystallization at 170°C for 72 hours, then cooled to 40°C. The product was separated into solid and mother liquor. The solid was washed with deionized water until the pH of the washing liquid was 8, and then dried at 120°C for 10 hours to obtain molecular sieve powder. The powder was pressed into tablets at a pressure of 20 MPa to obtain KL-type molecular sieve, denoted as ZT-3. TEM and XRD tests were performed on KL-type molecular sieve ZT-3. The test results were consistent with... Figure 1 and Figure 2 Similarly, the structure of KL-type molecular sieve ZT-3 is shown in Table 1.

[0094] The catalyst was prepared using the following steps:

[0095] S1. Take 50g of the ZT-3 prepared above as a carrier, and prepare an impregnation solution with lanthanum nitrate, so that the content of lanthanum nitrate in the impregnation solution, calculated as La, is 0.9% by weight (relative to the weight of the KL type molecular sieve). Pour ZT-3 and the impregnation solution into a 500mL flask (the liquid / solid volume ratio of the impregnation solution to ZT-3 is 1.5), and impregnate in a rotary vacuum evaporator at 25℃, 0.02MPa, and a rotational speed of 0.03m / s for 3h. Dry the solid under reduced pressure at 70℃, dry at 120℃ for 12h, and calcine in dry air at 350℃ and a gas / agent volume ratio of 700 for 4h to obtain a KL type molecular sieve containing Ce, denoted as ZT-3-Ce.

[0096] S2. Prepare an impregnation solution by mixing chloroplatinic acid and potassium chloride, such that the content of chloroplatinic acid (calculated as Pt) in the impregnation solution is 0.8% by weight and the content of potassium chloride (calculated as Cl) is 0.8% by weight (both relative to the weight of KL type molecular sieve). Pour ZT-2-Ce and the impregnation solution into a 500 mL flask (the liquid / solid volume ratio of the impregnation solution to ZT-2 is 1.5), and impregnate in a rotary vacuum evaporator at 25 °C, 0.02 MPa, and a rotational speed of 0.03 m / s for 3 h. Dry the solid under reduced pressure at 70 °C, dry at 120 °C for 12 h, calcine in dry air at 350 °C and a gas / agent volume ratio of 700 for 4 h, and then reduce with H2 at 480 °C and a gas / agent volume ratio of 500 for 4 h to obtain catalyst Cat-3, the composition of which is shown in Table 2.

[0097] Example 4

[0098] Similar to Example 1, except that pseudoboehmite powder was incorporated as a binder during the tableting process. After molding, the tablets were calcined in a muffle furnace at 500°C for 24 hours to obtain an alumina support containing an alumina binder, designated ZT-4, with an alumina binder content of 2.0 wt%. The structure is shown in Table 1. The support was subsequently impregnated to obtain catalyst Cat-4, the molecular sieve structure of which is shown in Table 1 and the catalyst composition in Table 2.

[0099] Example 5

[0100] Similar to Example 1, except that the content of potassium chloride (calculated as Cl) in the S2 impregnation step is 1.4% by weight, resulting in catalyst Cat-5. The molecular sieve structure is shown in Table 1 and the catalyst composition is shown in Table 2.

[0101] Example 6

[0102] Similar to Example 1, except that in the S2 impregnation step, the content of chloroplatinic acid in the impregnation solution, calculated as Pt, is 0.4% by weight, to obtain catalyst Cat-6. The molecular sieve structure is shown in Table 1 and the catalyst composition is shown in Table 2.

[0103] Example 7

[0104] Similar to Example 1, except that some of the K in the ZT-3 molecular sieve framework of Example 3 was replaced with H. Specifically, 1g of the support was placed in 30mL of a 0.1mol / L ammonia solution, heated to 70℃ and stirred for 1h. The product was dried at 120℃ for 12h and then calcined in a muffle furnace at 480℃ for 4h. The resulting molecular sieve material was designated ZT-7. ZT-7 was further subjected to the S1 impregnation step and the S2 impregnation step to obtain the catalyst Cat-7. The molecular sieve structure is shown in Table 1 and the catalyst composition is shown in Table 2.

[0105] Example 8

[0106] Similar to Example 1, except that the feed amount during the molecular sieve synthesis process was changed, so that the silica-alumina ratio of the molecular sieve was 2.65 and the K content was 18.3% by mass. The resulting molecular sieve was designated ZT-8. ZT-7 was then subjected to the S1 impregnation step and the S2 impregnation step to obtain the catalyst Cat-8. The molecular sieve structure is shown in Table 1 and the catalyst composition is shown in Table 2.

[0107] Example 9

[0108] Similar to Example 1, except that in the S1 impregnation step, the content of cerium nitrate (calculated as Ce) in the impregnation solution is 1.5% by weight (relative to the weight of KL type molecular sieve), to obtain catalyst Cat-9. The molecular sieve structure is shown in Table 1 and the catalyst composition is shown in Table 2.

[0109] Example 10

[0110] Similar to Example 1, except that in the S1 impregnation step, the content of cerium nitrate (calculated as Ce) in the impregnation solution is 1.5% by weight (relative to the weight of KL type molecular sieve), and in the S2 impregnation step, the content of chloroplatinic acid (calculated as Pt) in the impregnation solution is 0.5% by weight, thus obtaining catalyst Cat-10. The molecular sieve structure is shown in Table 1 and the catalyst composition is shown in Table 2.

[0111] Example 11

[0112] Similar to Example 1, except that 2.0 wt% silica was incorporated as a binder during the tableting process. After molding, the tablet was calcined in a muffle furnace at 500°C for 24 hours to obtain a support containing silica binder, designated ZT-11, with a silica binder content of 2.0 wt%. The structure is shown in Table 1. The support was then impregnated to obtain the catalyst Cat-11. The molecular sieve structure is shown in Table 1, and the catalyst composition is shown in Table 2.

[0113] Comparative Example 1

[0114] Same as Example 1, except that steps (1) and (2) are omitted, the KL-type molecular sieve in step S1 is replaced with the same weight of γ-Al2O3 support, and chloroplatinic acid, ammonium perrhenate and hydrochloric acid are prepared into an impregnation solution, so that the content of chloroplatinic acid in the impregnation solution is 0.24 wt% based on Pt, the content of ammonium perrhenate based on Re is 0.40 wt%, and the content of hydrochloric acid based on Cl is 1.1 wt% (all relative to the weight of alumina), and finally the comparative catalyst DBCat-1 is obtained. The support properties are shown in Table 1 and the catalyst composition is shown in Table 2.

[0115] Comparative Example 2

[0116] Same as Example 1, except that steps (1) and (2) are omitted, the KL-type molecular sieve in step S1 is replaced with the same weight of γ-Al2O3 support, and chloroplatinic acid, cerium nitrate and hydrochloric acid are prepared into an impregnation solution, so that the content of chloroplatinic acid in the impregnation solution is 1.0 wt% based on Pt, the content of cerium nitrate based on Ce is 0.50 wt%, and the content of hydrochloric acid based on Cl is 1.0 wt% (all relative to the weight of alumina), and finally the comparative catalyst DBCat-2 is obtained. The properties of the support are shown in Table 1 and the composition of the catalyst is shown in Table 2.

[0117] Comparative Example 3

[0118] Similar to Example 1, except that the KL-type molecular sieve was replaced with an HL molecular sieve, resulting in the comparative catalyst DBCat-3. The molecular sieve structure is shown in Table 1, and the catalyst composition is shown in Table 2. The preparation of the HL molecular sieve is as follows:

[0119] (1) Dissolve Al(OH)3 (aluminum source, mass fraction of 99%) and KOH (alkali source, mass fraction of 95%) in deionized water and heat to 90℃ to dissolve and obtain aluminum sol; add aluminum sol to silica sol (silicon source, mass fraction of 25.6%, calculated as SiO2) under stirring and stir for 0.5h to obtain a mixture gel;

[0120] (2) The mixture gel was transferred into a reaction vessel and subjected to hydrothermal crystallization treatment at 170°C for 72 hours. Then it was cooled to 40°C. The product was separated into solid and mother liquor. The solid was washed with deionized water until the pH of the washing liquid was 8. Then it was dried at 120°C for 10 hours to obtain molecular sieve powder. The powder was pressed into tablets under a pressure of 20 MPa to obtain KL type molecular sieve particles.

[0121] 1g of the above KL type molecular sieve particles were placed in 30mL of 0.1mol / L ammonia solution, heated to 70℃ and stirred for 12h. After drying the product at 120℃ for 12h, it was calcined in a muffle furnace at 480℃ for 4h to obtain HL molecular sieve, denoted as DBZT-3. The molecular sieve structure is shown in Table 1 and the catalyst composition is shown in Table 2.

[0122] Comparative Example 4

[0123] Similar to Example 1, the difference lies in the inclusion of pseudoboehmite powder as a binder during the tableting process. After molding, the tablets are calcined in a muffle furnace at 500°C for 24 hours to obtain an alumina carrier containing an alumina binder, designated DBZT-4, with an alumina binder content of 10.0 wt%. The structure is shown in Table 1. The carrier is then impregnated to obtain the catalyst DBCat-4. The carrier structure is shown in Table 1, and the catalyst composition is shown in Table 2.

[0124] Comparative Example 5

[0125] Similar to Example 1, except that the impregnation process does not include step S1, i.e. the catalyst is not loaded with rare earth elements, resulting in the comparative catalyst DBCat-5. The molecular sieve structure is shown in Table 1 and the catalyst composition is shown in Table 2.

[0126] Table 1

[0127]

[0128]

[0129] Table 2

[0130]

[0131]

[0132] Test Example 1

[0133] 1g of catalysts Cat-1 to Cat-10 from Examples 1-10 and catalysts DBCat-1 to DBCat-4 from Comparative Examples 1-4 were loaded into a microreactor. Naphtha from Fischer-Tropsch synthesis was used as feedstock, and the feedstock composition is shown in Table 3. The reforming performance of the catalysts was evaluated under the following conditions: reaction temperature 480℃, pressure 0.85MPa, and naphtha feed mass hourly space velocity 4.0h. -1 The hydrogen / hydrocarbon volume ratio was 1000, and the reaction was carried out for 24 hours. The evaluation results are shown in Table 4.

[0134] Table 3

[0135]

[0136]

[0137] Table 4

[0138]

[0139] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A naphtha reforming catalyst, characterized in that, The catalyst comprises a support and an active component supported on the support, wherein, The carrier includes a KL-type molecular sieve, and the content of oxide binder in the carrier is not higher than 5 wt%. The active components include Group VIII metals and rare earth elements.

2. The catalyst according to claim 1, wherein, Based on the total weight of the catalyst, the content of the active component in the catalyst, calculated by element, is 0.5-10 wt%; and / or The oxide binder content in the carrier is not higher than 1 wt%; and / or The oxide binder includes at least one of aluminum oxide, silicon oxide, and calcium oxide, preferably aluminum oxide.

3. The catalyst according to claim 1 or 2, wherein, The active component further includes halogens; preferably, Based on the total weight of the catalyst, the halogen content in the catalyst, calculated as an element, is 0.5-1.5 wt%, preferably 0.5-1 wt%. and / or The halogen is selected from at least one of F, Cl, Br and I, preferably F and / or Cl; More preferably, In the catalyst, the weight ratio of Group VIII metal elements to halogens is 1:(0.3-3), preferably 1:(0.8-2).

4. The catalyst according to any one of claims 1-3, wherein, The KL-type molecular sieve contains 8-20 wt% alkali metal elements, preferably 12-20 wt%; more preferably, The alkali metal element includes K and optionally at least one of Na, Rb and Cs, preferably K.

5. The catalyst according to any one of claims 1-4, wherein, The molar ratio of SiO2 to Al2O3 in the KL-type molecular sieve is 2.5-3.5, preferably 2.7-3; and / or The relative crystallinity of the KL-type molecular sieve is 90-100%, preferably 95-100%; and / or The average particle size of the KL-type molecular sieve is 300-2000 nm, preferably 500-1200 nm.

6. The catalyst according to any one of claims 1-5, wherein, Based on the total weight of the catalyst, the content of the Group VIII metal element, calculated as an element, is 0.2-1.5 wt%, preferably 0.5-1 wt%; and / or Based on the total weight of the catalyst, the rare earth element content is 0.1-3 wt%, preferably 0.1-1 wt%; and / or In the catalyst, the weight ratio of Group VIII metal elements to rare earth elements is 1:(0.1-6), preferably 1:(0.1-2; and / or The Group VIII metallic element is selected from at least one of Pt, Ru, and Rh, preferably Pt; and / or The rare earth element is selected from at least one of La, Ce and Pr, preferably La and / or Ce.

7. A method for preparing the catalyst according to any one of claims 1-6, characterized in that, The preparation method includes the following steps: S1. A solution containing rare earth elements, group VIII metal elements and optionally halogens is contacted with a support to obtain a catalyst precursor; S2. The catalyst precursor is dried, calcined, and reduced.

8. The preparation method according to claim 7, wherein, Step S1 includes the following steps: (1) The solution containing rare earth elements is brought into contact with the carrier, dried and calcined to obtain the carrier containing rare earth elements. (2) A solution containing Group VIII metal elements and optionally halogens is contacted with a support containing rare earth elements to obtain a catalyst precursor.

9. The application of the catalyst according to any one of claims 1-6 and / or the catalyst prepared by the preparation method according to claim 7 or 8 in naphtha catalytic reforming.

10. A method for naphtha catalytic reforming, characterized in that, The method includes: reacting naphtha with hydrogen under catalytic conditions; The catalyst is the catalyst according to any one of claims 1-6 and / or the catalyst prepared by the preparation method according to claim 7 or 8; Preferably, The naphtha is Fischer-Tropsch synthetic naphtha, preferably with a total mass fraction of n-alkanes and isoalkanes ≥70%, more preferably with a total mass fraction of n-alkanes and isoalkanes ≥90%; and / or The conditions for the contact reaction include: The temperature is 420-520℃, preferably 450-500℃; and / or The pressure is 0.3-1.2 MPa, preferably 0.3-1.2 MPa; and / or The mass hourly space velocity (MSV) of naphtha feed is 1-4 h⁻¹. -1 Preferably 1.5-2.5h -1 ; and / or The hydrogen / hydrocarbon volume ratio is 600-1800, preferably 600-1200.

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