Hydroisomerization aromatization catalyst and method for making same

Abstract

The present application relates to the technical field of olefin isomerization and aromatization, in particular to a hydrogenation isomerization aromatization catalyst and a preparation method thereof. The catalyst comprises 0.2-4.5 wt% of a main dehydrogenation metal component, 0.2-3.5 wt% of a main hydrogenation metal component, 1-10 wt% of an auxiliary metal component and 82-98.6 wt% of a carrier, based on the total mass of the catalyst; wherein the main dehydrogenation metal component is selected from the oxides of metals in group IIIA, the main hydrogenation metal component is selected from the oxides of metals in group VIII, and the auxiliary metal component is selected from the oxysulfides of metals in group IIB. The catalyst provided in the present application can simultaneously have high olefin conversion activity and high isomerization aromatization selectivity, and also has the advantages of less cracking side reactions and good stability, and can catalyze the isomerization and aromatization of olefins, and can be used for the production of high-octane components for gasoline pool and / or high-value-added aromatic hydrocarbons.

Description

Technical Field

[0001] This invention relates to the field of olefin isomerization and aromatization technology, specifically to a hydrogenation isomerization and aromatization catalyst and its preparation method. Background Technology

[0002] Given my country's significant demand for light aromatics and high-octane gasoline components, efficient utilization of olefin-rich resources such as naphtha, reformate residue, light gasoline, and catalytic gasoline is crucial. For instance, aromatizing refinery gases rich in olefins can yield high-value-added aromatic compounds, thereby improving refinery economic efficiency.

[0003] Bifunctional catalysts are widely used in reactions such as olefin isomerization and light hydrocarbon aromatization. These catalysts possess both acidic centers, promoting isomerization, aromatization, and cracking of olefins, and metallic active centers, enabling the continuous dehydrogenation of olefins via the hydrogenation of isomeric olefins to produce high-octane components. However, olefin catalytic reactions are complex, and current olefin hydrogenation-isomeric-aromatication catalysts generally suffer from numerous problems, including low olefin conversion activity, poor isomerization / aromatication selectivity, strong cracking side reactions, and a tendency to coke, which affects catalyst activity and stability.

[0004] CN112973772A discloses a gasoline aromatization isomerization catalyst and its preparation method. The gasoline aromatization isomerization catalyst, by weight percentage, comprises 37-85% nano-HZSM-5 grown along the 051 crystal plane, 5-58% alumina, and 2-10% active metal components. The active metal components are one or more oxides of Group VIB, Group VIIB, Group IIB, lanthanides, Group VIII, and Group IIIA elements. Preferably, the Group VIB elements are Mo and W; preferably, the Group IIB elements are Zn and Cd; preferably, the lanthanides are La and Ce; more preferably, the Group VIII elements are Co and Ni; and even more preferably, the Group IIIA elements are B and Ga. This catalyst is used for the olefin reduction reaction of gasoline with high olefin content. It can significantly reduce the olefin content of gasoline while increasing the octane number of the product by 1.7 to 7 units through isomerization and aromatization reactions, with a desulfurization rate of >45%, gasoline product yield of >98%, and service life of >3000 hours. However, this catalyst only uses HZSM-5 single molecular sieve as catalyst support, which has too strong surface acidity. This will aggravate side reactions such as cracking and aromatic alkylation, resulting in a later product dry point (the final boiling point of gasoline product continuously increases), and the catalyst is prone to carbon deposition.

[0005] CN114471677A discloses a hydroisomerization catalyst and its support. The catalyst support is prepared by further modification of a mixture of modified molecular sieve and amorphous inorganic porous material. The modification includes metal and / or acid modification. The mass ratio of the modified molecular sieve to the inorganic porous material is 2:3 to 5:1. The modified molecular sieve is obtained by modifying a raw material molecular sieve containing a ten-membered ring structure with metal and / or acid, followed by drying and calcination. The molecular sieve is selected from at least one of ZSM-5, SAPO-11, EU-1, ITQ-13, ZSM-22, MCM-22, NU-87, ZSM-23, ZSM-35, and ZSM-48. The modifying metal is selected from one or more of potassium, magnesium, calcium, strontium, barium, copper, zinc, gallium, and tin. A noble metal is used as the active component, selected from one or two compounds of Pt, Pd, Ru, Rh, Re, and Ir. The catalyst is used to address the problem of high cloud point in existing lubricating oil base oil production processes. It exhibits strong aromatic saturation and excellent hydroisomerization performance. However, because the catalyst uses a precious metal as its active metal, its catalytic activity is concentrated in the hydrogenation process, which can lead to aromatic hydrogenation saturation and a decrease in aromatic content. Therefore, it is not suitable for aromatization reactions that require a significant increase in octane number.

[0006] CN107570207A discloses a hydroisomerization catalyst for non-precious metal distillate oils, comprising the following components: a TON / MFI composite molecular sieve, alumina or silica as a support, and Group VIII and Group VIB non-precious metal elements as active components. Based on the weight percentage of the catalyst, the content of each component is: 42-81% TON / MFI composite molecular sieve, 9-28% alumina or silica, 5-9% Group VIII metal oxides, and 1-25% Group VIB metal oxides; the Group VIII metal element is Ni and / or Co, and the Group VIB metal element is Mo and / or W. However, this catalyst is synthesized in situ using a gel-sol method to create a mesoporous silica-alumina molecular sieve with a TON / MFI composite topology. The preparation process is complex and costly, and the in-situ synthesis process easily forms eutectic molecular sieves, making it difficult to control the proportion of the composite molecular sieve and thus challenging the control of the shape-selective function of the molecular sieve.

[0007] Therefore, there is an urgent need to provide a hydroisomerization catalyst that can improve the activity of olefin conversion, enhance the selectivity of isoalkanes and aromatics, suppress carbon deposition and coking side reactions, and extend the catalyst life. Summary of the Invention

[0008] The purpose of this invention is to overcome at least one of the problems existing in the prior art, such as low olefin conversion activity, poor isomerization / aromatization selectivity, strong cracking side reactions, and easy coking affecting catalyst activity and stability. This invention provides a hydroisomerization-aromatization catalyst and its preparation method. This catalyst can construct a highly efficient dehydrogenation center-moderate hydrogenation center-synergistic acid center, simultaneously possessing high olefin conversion activity and high isomerization-aromatization selectivity, as well as the advantages of few cracking side reactions and good stability. It can catalyze the isomerization-aromatization reaction of olefins and can be used for the production of high-octane components or high-value-added aromatics in blended gasoline pools.

[0009] To achieve the above objectives, a first aspect of the present invention provides a hydroisomerization aromatization catalyst, wherein, based on the total mass of the catalyst, the catalyst comprises 0.2-4.5 wt% of a main dehydrogenation metal component, 0.2-3.5 wt% of a main hydrogenation metal component, 1-10 wt% of a cooperating metal component, and 82-98.6 wt% of a support; wherein the main dehydrogenation metal component is selected from oxides of Group IIIA metals, the main hydrogenation metal component is selected from oxides of Group VIII metals, and the cooperating metal component is selected from sulfur oxides of Group IIB metals.

[0010] A second aspect of the present invention provides a method for preparing a hydroisomerization aromatization catalyst, wherein the method comprises the following steps:

[0011] (1) The main dehydrogenation metal component precursor, the main hydrogenation metal component precursor and the auxiliary metal component precursor are loaded on a support to obtain a catalyst precursor.

[0012] The main dehydrogenation metal component precursor is selected from nitrates of group IIIA metal elements, the main hydrogenation metal component precursor is selected from nitrates of group VIII metal elements, and the auxiliary metal component precursor is selected from sulfates of group IIB metal elements.

[0013] (2) The catalyst precursor is calcined to obtain the catalyst.

[0014] The beneficial technical effects achieved by the present invention through the above technical solution are as follows:

[0015] 1) The catalyst provided in this invention, by adding a supporting metal component, can not only prevent the loss of the main dehydrogenation metal component and the main hydrogenation metal component and significantly improve the stability of the hydroisomerization aromatization catalyst, but also adjust the surface acidity of the hydroisomerization aromatization catalyst, reduce cracking side reactions, and improve the hydroisomerization and hydroaromatication performance of the catalyst. It can catalyze the isomerization and aromatization reaction of olefins and can be applied to the production of high octane components and / or high value-added aromatics in blended gasoline pools.

[0016] 2) The catalyst provided in this invention, by combining one-dimensional and three-dimensional pore structure molecular sieves and adjusting the content of one-dimensional and three-dimensional pore structure molecular sieves, is conducive to giving full play to the pore confinement function and shape selection of molecular sieves, avoiding excessive aromatization, achieving moderate aromatization, helping to reduce coke generation, reduce catalyst carbon deposition, and extend catalyst life.

[0017] 3) The catalyst provided in this invention can achieve the effect of moderate isomerization and aromatization, and has the advantages of excellent olefin conversion activity, high isomerization and aromatization selectivity, small dry point shift, strong anti-carbon deposition ability, good stability, and can reduce side reactions such as cracking and aromatic alkylation.

[0018] 4) The catalyst preparation method provided in this invention is simple to operate, has mild conditions, and produces no waste, making it suitable for industrial application. Attached Figure Description

[0019] Figure 1 These are the XRD patterns of the catalysts prepared in Examples 1-3 and Comparative Example 3. Detailed Implementation

[0020] 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.

[0021] A first aspect of the present invention provides a hydroisomerization aromatization catalyst, wherein, based on the total mass of the catalyst, the catalyst comprises 0.2-4.5 wt% of a main dehydrogenation metal component, 0.2-3.5 wt% of a main hydrogenation metal component, 1-10 wt% of a co-metal component and 82-98.6 wt% of a support;

[0022] The primary dehydrogenation metal component is selected from oxides of Group IIIA metals, the primary hydrogenation metal component is selected from oxides of Group VIII metals, and the auxiliary metal component is selected from sulfur oxides of Group IIB metals.

[0023] In this invention, metal sulfur oxides refer to oxygen- and sulfur-containing metal compounds generated after the calcination of metal sulfates. The metal sulfur oxides in the catalyst can be detected by characterization methods such as XRF. The inventors have discovered that introducing group IIB metal sulfur oxides into the hydroisomerization aromatization catalyst can form stronger binding forces with the main hydrogenation and dehydrogenation metal components. This not only prevents the loss of the main dehydrogenation and hydrogenation metal components and significantly improves the stability of the hydroisomerization aromatization catalyst, but also adjusts the surface acidity of the catalyst, thereby improving the catalyst's ability to suppress cracking side reactions and olefin conversion, and promoting the selective conversion of olefins to isoalkanes and aromatics, i.e., conversion to high-octane components.

[0024] In a preferred embodiment of the present invention, the catalyst comprises, by total mass, 1-3 wt% of a primary dehydrogenation metal component, 0.5-1.5 wt% of a primary hydrogenation metal component, 3-7 wt% of a co-metal component, and 88.5-95.5 wt% of a support.

[0025] In a preferred embodiment of the present invention, the mass ratio of the main dehydrogenation metal component, the main hydrogenation metal component, and the auxiliary metal component is 1:0.15-6.5:1-15, preferably 1:0.25-1.5:2.5-4.

[0026] In this invention, by controlling the content of the main dehydrogenation metal component, the main hydrogenation metal component, and the auxiliary metal component, it is helpful to construct a "highly efficient dehydrogenation center - moderately hydrogenation center - synergistic acid center", which further enhances the catalytic efficiency of the main reaction olefin isomerization and olefin aromatization, while avoiding the direct hydrogenation of n-olefins to n-alkanes (low octane number) caused by strong hydrogenation centers, thus realizing the directional conversion of olefins to high octane number components.

[0027] In a preferred embodiment of the present invention, the Group IIIA metal is gallium and / or indium; the Group VIII metal is one or more of cobalt, nickel, copper, and ruthenium; and the Group IIB metal is zinc.

[0028] In a preferred embodiment of the present invention, the carrier comprises 60-95 wt%, preferably 70-90 wt%, of a composite molecular sieve and 5-40 wt%, preferably 10-30 wt%, of a binder, based on the total mass of the carrier; wherein the composite molecular sieve comprises a one-dimensional pore structure molecular sieve and a three-dimensional pore structure molecular sieve.

[0029] In a preferred embodiment of the present invention, the mass ratio of the one-dimensional porous molecular sieve to the three-dimensional porous molecular sieve is 1:0.1-2.5.

[0030] In this invention, one-dimensional and three-dimensional porous molecular sieves can produce a synergistic effect. By adjusting the content of one-dimensional and three-dimensional porous molecular sieves, it is beneficial to give full play to the pore confinement and shape selection effect of molecular sieves. In addition, by adjusting the acid content of the composite molecular sieve, excessive aromatization can be avoided, the amount of coke generated can be reduced, the amount of catalyst carbon deposit and C3-C5 generation can be reduced, and the catalyst life can be extended.

[0031] In a preferred embodiment of the present invention, the one-dimensional porous molecular sieve is one or more of MOR, ZSM-22, MCM-22, NU-87, ZSM-23, ZSM-48, and SAPO-41.

[0032] In a preferred embodiment of the present invention, the three-dimensional porous molecular sieve is one or more of ZSM5, ZSM-11, β molecular sieve, and Y molecular sieve.

[0033] In a preferred embodiment of the present invention, the binder is alumina and / or silicon dioxide, preferably alumina.

[0034] A second aspect of the present invention provides a method for preparing a hydroisomerization aromatization catalyst, wherein the method comprises the following steps:

[0035] (1) The main dehydrogenation metal component precursor, the main hydrogenation metal component precursor and the auxiliary metal component precursor are loaded on a support to obtain a catalyst precursor.

[0036] The main dehydrogenation metal component precursor is selected from nitrates of group IIIA metal elements, the main hydrogenation metal component precursor is selected from nitrates of group VIII metal elements, and the auxiliary metal component precursor is selected from sulfates of group IIB metal elements.

[0037] (2) The catalyst precursor is calcined to obtain the catalyst.

[0038] In step (1):

[0039] In a preferred embodiment of the present invention, the main dehydrogenation metal component precursor is gallium nitrate and / or indium nitrate.

[0040] In a preferred embodiment of the present invention, the main hydrogenation metal component precursor is one or more of cobalt nitrate, nickel nitrate, copper nitrate, and ruthenium nitrate.

[0041] In a preferred embodiment of the present invention, the auxiliary metal component precursor is zinc sulfate. In this invention, unlike zinc nitrate where nitrate decomposes upon calcination, sulfate in zinc sulfate can exist on the surface and in the channels of the molecular sieve, generating sulfur oxides upon calcination, which can modify the strong acidity on the surface of the support. Simultaneously, the sulfur oxides can promote the inter-modification of the auxiliary metal with the main dehydrogenation metal component and the main hydrogenation metal component on the support, exerting a synergistic effect with the acidic centers and reducing the loss of the main dehydrogenation metal component and the main hydrogenation metal component.

[0042] In one embodiment of the present invention, the amounts of the main dehydrogenation metal component precursor, the main hydrogenation metal component precursor, and the auxiliary metal component precursor are such that the prepared catalyst contains 0.2-4.5 wt%, preferably 1-3 wt% of the main dehydrogenation metal component, 0.2-3.5 wt%, preferably 0.5-1.5 wt% of the main hydrogenation metal component, and 1-10 wt%, preferably 3-7 wt% of the auxiliary metal component.

[0043] In one embodiment of the present invention, the amounts of the main dehydrogenation metal component precursor, the main hydrogenation metal component precursor, and the auxiliary metal component precursor are such that the mass ratio of the main dehydrogenation metal component, the main hydrogenation metal component, and the auxiliary metal component in the prepared catalyst is 1:0.15-6.5:1-15, preferably 1:0.25-1.5:2.5-4.

[0044] In one embodiment of the present invention, the method for preparing the carrier includes: mixing a one-dimensional porous molecular sieve, a three-dimensional porous molecular sieve, a binder precursor, a molding aid, an adhesive, and water, extruding the mixture, and then calcining it to obtain the carrier.

[0045] In one embodiment of the present invention, the one-dimensional porous molecular sieve is one or more of MOR, ZSM-22, MCM-22, NU-87, ZSM-23, ZSM-48, and SAPO-41.

[0046] In a preferred embodiment of the present invention, the three-dimensional porous molecular sieve is one or more of ZSM5, ZSM11, β molecular sieve, and γ molecular sieve.

[0047] In a preferred embodiment of the present invention, the binder precursor is one or more of boehmite, silica sol, and alumina sol, preferably boehmite.

[0048] In a preferred embodiment of the present invention, the molding aid is one or more of guar gum powder, starch, and cellulose, preferably guar gum powder.

[0049] In a preferred embodiment of the present invention, the adhesive is one or more of nitric acid solution, acetic acid solution, and citric acid solution, preferably nitric acid solution. In this invention, the concentration of the nitric acid solution, acetic acid solution, and citric acid solution can be 30-68 wt%, preferably 65-68 wt%.

[0050] In a preferred embodiment of the present invention, the mass ratio of the one-dimensional porous molecular sieve to the three-dimensional porous molecular sieve is 1:0.1-2.5.

[0051] In a preferred embodiment of the present invention, the amounts of the one-dimensional porous molecular sieve, the three-dimensional porous molecular sieve, and the binder precursor are such that the catalyst support prepared comprises 60-95 wt%, preferably 70-90 wt%, of a composite molecular sieve and 5-40 wt%, preferably 10-30 wt%, of a binder. In this invention, the amounts of molding aids, adhesives, and water can be added according to conventional practices in the art, and the present invention does not impose any particular limitations on them.

[0052] In a preferred embodiment of the present invention, a drying process is performed before calcination after extrusion molding. The drying temperature is 100-160°C, and the drying time is 10-14 hours.

[0053] In a preferred embodiment of the present invention, the roasting conditions include: a roasting temperature of 500-600°C and a roasting time of 3-6 hours.

[0054] In a preferred embodiment of the present invention, the operation of the loading includes: first impregnating the support in an impregnation solution containing a main dehydrogenation metal component precursor, a main hydrogenation metal component precursor and a co-metal component precursor, and then aging it to obtain a catalyst precursor.

[0055] In a preferred embodiment of the present invention, the impregnation is an equal-volume impregnation. In this invention, the impregnation solution is prepared by testing the water absorption rate of the support, which not only increases the impregnation rate but also improves the dispersibility of the main dehydrogenation metal component precursor, the main hydrogenation metal component precursor, and the auxiliary metal component precursor, thereby improving the stability of the catalyst.

[0056] In a preferred embodiment of the present invention, the impregnation and aging are carried out in a closed device; wherein, the impregnation operation is to shake at room temperature for 5-20 minutes; and the aging operation is to stand at room temperature for 4-12 hours.

[0057] In this invention, shaking allows for a more uniform distribution of the main dehydrogenation metal component precursor, the main hydrogenation metal component precursor, and the auxiliary metal component precursor on the support. The aging process avoids the drying effect of circulating air on the impregnation solution, ensuring that the hydrogenation metal component precursor and the auxiliary metal component precursor are completely adsorbed onto the support. Through shaking and aging, the impregnation process is ensured to be more thorough, resulting in better dispersion and utilization of the metal components in the prepared catalyst, and moderate interaction forces between the support and the metal components, thus improving the catalyst's hydroisomerization / aromatization performance. Room temperature has a generally accepted meaning, and this invention does not specifically limit it.

[0058] In step (2):

[0059] In a preferred embodiment of the present invention, the catalyst precursor is dried before calcination. The drying temperature is 100-160°C, and the drying time is 3-6 hours.

[0060] In a preferred embodiment of the present invention, the calcination operating conditions include: a calcination temperature of 400-600℃ and a calcination time of 3-6h.

[0061] In this invention, by controlling the calcination conditions, the precursor of the auxiliary metal component can be converted into a compound containing oxygen and sulfur. The auxiliary metal sulfur oxide not only prevents the loss of the main dehydrogenation metal component and the main hydrogenation metal component, significantly improving the stability of the hydroisomerization aromatization catalyst, but also adjusts the surface acidity of the hydroisomerization aromatization catalyst, reduces cracking side reactions, and improves the hydroisomerization and hydroaromatication performance of the catalyst.

[0062] The present invention will be described in detail below through embodiments.

[0063] Among them, MOR was purchased from Zhuoyue Environmental New Materials (Shanghai) Co., Ltd., product model NF-H00-I02M; ZSM-5 was purchased from Zhuoyue Environmental New Materials (Shanghai) Co., Ltd., product model NA-H05-B02M; SAPO-41 was purchased from Zhuoyue Environmental New Materials (Shanghai) Co., Ltd., product model NB-H41-B02L; ZSM-11 was purchased from Tianjin Nanhua Catalyst Co., Ltd., product model NKF-21 (ZSM11); ZSM-23 was purchased from Zhuoyue Environmental New Materials (Shanghai) Co., Ltd., product model NA-H23-P04M; and β-molecular sieve was purchased from Zhuoyue Environmental New Materials (Shanghai) Co., Ltd., product model NE-H00-02. The alumina content in the pseudoboehmite was 70 wt%.

[0064] Example 1

[0065] (1) 157.5g of MOR molecular sieve, 67.5g of ZSM-5 molecular sieve, 35.8g of pseudoboehmite and 5g of guar gum powder were put into a kneader and dry-mixed for 10min. Then, 7.7g of 65wt% nitric acid and 75g of water were added and mixed for 15min. Then, the mixture was sent to an extruder for extrusion. After that, it was dried at 120℃ for 12h and calcined at 550℃ for 5h to obtain the carrier.

[0066] Take 20g of the above-mentioned support and prepare an impregnation solution according to the equal volume impregnation method. The impregnation solution contains 5.59g of zinc sulfate, 1.32g of nickel nitrate and 1.85g of gallium nitrate. Add the support to the prepared impregnation solution, shake in a sealed container for 10min, let stand and age for 4h, take it out and dry at 120℃ for 4h to obtain the catalyst precursor.

[0067] (2) The obtained catalyst precursor was transferred to a muffle furnace and calcined at 600°C for 4 hours to obtain the catalyst.

[0068] Example 2

[0069] (1) 100g SAPO-41 molecular sieve, 100g ZSM-11 molecular sieve, 71.4g pseudoboehmite, and 12.5g guar gum powder were put into a kneader and dry-mixed for 10min. Then, 7.7g 65wt% nitric acid and 75g water were added and mixed for 15min. The mixture was then fed into an extruder for extrusion. After that, it was dried at 120℃ for 12h and calcined at 550℃ for 5h to obtain the carrier.

[0070] Take 20g of the above-mentioned support and prepare an impregnation solution according to the equal volume impregnation method. The impregnation solution contains 3.84g zinc sulfate, 0.84g cobalt nitrate, and 1.19g gallium nitrate. Add the support to the prepared impregnation solution, shake in a sealed container for 10min, let stand and age for 8h, take it out and dry at 120℃ for 4h to obtain the catalyst precursor.

[0071] (2) The obtained catalyst precursor was transferred to a muffle furnace and calcined at 550°C for 5 hours to obtain the catalyst.

[0072] Example 3

[0073] (1) 52.5g ZSM-23 molecular sieve, 122.5g β molecular sieve, 107.1g pseudoboehmite and 7.5g guar gum powder were put into a kneader and dry-mixed for 10min. Then 7.7g 65wt% nitric acid and 75g water were added and mixed for 15min. Then the mixture was sent to an extruder for extrusion. After that, it was dried at 120℃ for 12h and calcined at 550℃ for 5h to obtain the carrier.

[0074] Take 20g of the above-mentioned carrier and prepare an impregnation solution according to the equal volume impregnation method. The impregnation solution contains 2.22g of zinc sulfate, 0.32g of copper nitrate, and 0.58g of indium nitrate. Add the carrier to the prepared impregnation solution, shake in a sealed container for 10min, let stand and age for 12h, take it out and dry at 120℃ for 4h to obtain the catalyst precursor.

[0075] (2) The obtained catalyst precursor was transferred to a muffle furnace and calcined at 500°C for 6 hours to obtain the catalyst.

[0076] Example 4

[0077] Same as Example 1, except that the impregnation solution contains 5.53g zinc sulfate, 2.61g nickel nitrate and 0.30g gallium nitrate.

[0078] Comparative Example 1

[0079] Same as Example 1, except that the 5.59g zinc sulfate in the impregnation solution was replaced with 5.78g zinc nitrate.

[0080] Comparative Example 2

[0081] Same as Example 1, except that the impregnation solution contains 1.55g zinc sulfate, 1.71g nickel nitrate and 3.00g gallium nitrate.

[0082] Comparative Example 3

[0083] Same as Example 1, except that 67.5g of MOR molecular sieve and 157.5g of ZSM-5 molecular sieve were replaced with 225g of ZSM-5 molecular sieve.

[0084] Test Example 1

[0085] The component content of the catalysts prepared in the examples and comparative examples was tested using X-ray fluorescence spectrometry. The test results are shown in Table 1, and the component content of the support is shown in Table 2.

[0086] Table 1

[0087]

[0088]

[0089] Table 2

[0090]

[0091] Test Example 2

[0092] The catalysts prepared in Examples 1-3 and Comparative Example 3 were characterized by XRD, and the results are as follows: Figure 1 As shown. Among them, Figure 1In this context, Cat1-4 represent the catalysts prepared in Examples 1-3 and Comparative Example 3, respectively. Figure 1 It can be seen that the XRD characteristic peaks in Examples 1-3 are composite characteristic peaks of the one-dimensional molecular sieve and the three-dimensional molecular sieve, proving that the corresponding composite molecular sieve was prepared. The catalyst prepared in Comparative Example 3 is supported by the three-dimensional molecular sieve ZSM-5. The XRD characteristic peaks show that only the characteristic peaks of ZSM-5 are present, which are significantly different from the mixed characteristic peaks of the one-dimensional / three-dimensional molecular sieves in Cat1-3.

[0093] and, Figure 1 No characteristic peaks of the metal active component were detected in Cat1-4, indicating that the metal active component is highly dispersed in the catalyst.

[0094] Test Example 3

[0095] Catalyst evaluation process: The catalysts prepared in the examples and comparative examples were respectively loaded into fixed-bed reactors. The catalysts were first pre-sulfurized using straight-run gasoline containing 3 wt% CS2, at a sulfidation pressure of 2.0 MPa and a hydrogen-to-oil volume ratio of 300:1, at 230℃ and 320℃ for 8 hours respectively. After sulfidation, the catalysts were fed into Liaoyang Petrochemical catalytic gasoline feedstock for reaction at a reaction temperature of 380℃ and a volume hourly space velocity (VHSV) of 1.5 h⁻¹. -1 The reaction was carried out under a reaction pressure of 2 MPa to obtain the product oil. Samples were taken for analysis after 48 hours of reaction. The test results of the Liaoyang Petrochemical catalytic gasoline feedstock before and after the hydroisomerization and aromatization reaction are shown in Table 3, and the test results of the carbon content in the catalyst after the reaction are shown in Table 4.

[0096] Table 3

[0097]

[0098] Note: △ in Table 3 represents the amount of each component that has decreased or increased compared to the raw materials.

[0099] As shown in Table 3, the catalysts provided in Examples 1-4 can significantly reduce the olefin content in the product oil, increase the content of aromatics and isoalkanes in the product oil, and significantly reduce the ΔC3-C5 produced by cracking. They can effectively inhibit the cracking reaction and achieve efficient conversion of olefins in the feedstock oil into high-octane components such as isoalkanes and aromatics.

[0100] Comparing Examples 1 and 4 reveals that, within the scope defined by this invention, adjusting the ratio of the main dehydrogenation metal component to the main hydrogenation metal component can further reduce the olefin content and increase the aromatic content in the product oil. By enhancing the catalytic efficiency of the main reaction olefin isomerization or olefin aromatization, the direct hydrogenation of n-olefins (low octane number) caused by strong hydrogenation centers is avoided, thus achieving the directional conversion of olefins to high-octane components. In Example 1, when the proportion of the main dehydrogenation metal is high, aromatic components can be generated appropriately, effectively balancing the isomerization and aromatization reaction and avoiding the coke precursor generated by excessive aromatization.

[0101] By comparing Example 1 and Comparative Example 1, it can be seen that, compared with zinc oxide, zinc exists in the form of sulfur oxides, which can significantly inhibit the ΔC3-C5 produced by cracking, and increase the content of aromatics and isoalkanes in the product oil, while reducing the content of olefins.

[0102] By comparing Example 1 and Comparative Example 2, it can be seen that when the content of the main dehydrogenation metal component is too high, the catalyst has poor activity for olefin conversion.

[0103] By comparing Example 1 and Comparative Example 3, it can be seen that the synergistic effect of one-dimensional porous molecular sieve and three-dimensional porous molecular sieve can significantly reduce the formation of ΔC3-C5 byproducts and improve the selectivity of isomerization and aromatization, resulting in high-quality product oil.

[0104] Table 4

[0105]

[0106]

[0107] As shown in Table 4, after a period of reaction under the same conditions, the carbon content of the catalysts in Examples 1-4 and Comparative Examples 1 and 2 was significantly lower than that in Comparative Example 3. This indicates that one-dimensional and three-dimensional porous molecular sieves can produce a synergistic effect, which helps to reduce the occurrence of carbon deposition side reactions such as condensation and coking, avoid excessive aromatization, reduce coke generation, reduce catalyst carbon deposition, extend catalyst life, and save production costs.

[0108] 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 hydroisomerization aromatization catalyst, characterized in that, Based on the total mass of the catalyst, the catalyst comprises 1-3 wt% of the main dehydrogenation metal component, 0.5-1.5 wt% of the main hydrogenation metal component, 3-7 wt% of the auxiliary metal component and 88.5-95.5 wt% of the support; Wherein, the main dehydrogenation metal component is selected from oxides of Group IIIA metals, the main hydrogenation metal component is selected from oxides of Group VIII metals, and the auxiliary metal component is selected from sulfur oxides of Group IIB metals; Wherein, the Group IIIA metal is gallium and / or indium; the Group VIII metal is one or more of cobalt, nickel, copper, and ruthenium; and the Group IIB metal is zinc. Based on the total mass of the carrier, the carrier comprises 60-95 wt% composite molecular sieve and 5-40 wt% binder; wherein the composite molecular sieve comprises one-dimensional porous molecular sieve and three-dimensional porous molecular sieve; the mass ratio of the one-dimensional porous molecular sieve to the three-dimensional porous molecular sieve is 1:0.1-2.5; The hydroisomerization aromatization catalyst is prepared by the following method: Includes the following steps: (1) The main dehydrogenation metal component precursor, the main hydrogenation metal component precursor and the auxiliary metal component precursor are loaded on a support to obtain the catalyst precursor; The main dehydrogenation metal component precursor is selected from nitrates of group IIIA metal elements, the main hydrogenation metal component precursor is selected from nitrates of group VIII metal elements, and the auxiliary metal component precursor is selected from sulfates of group IIB metal elements. (2) The catalyst precursor is calcined to obtain the catalyst; The calcination operating conditions include a calcination temperature of 400-600℃.

2. The catalyst according to claim 1, wherein, The one-dimensional porous molecular sieve is one or more of MOR, ZSM-22, MCM-22, NU-87, ZSM-23, ZSM-48, and SAPO-41; And / or, the three-dimensional porous molecular sieve is one or more of ZSM5, ZSM11, β molecular sieve, and Y molecular sieve; And / or, the adhesive is aluminum oxide and / or silicon dioxide.

3. A method for preparing the hydroisomerization aromatization catalyst according to claim 1 or 2, characterized in that, The method includes the following steps: (1) The main dehydrogenation metal component precursor, the main hydrogenation metal component precursor and the auxiliary metal component precursor are loaded on a support to obtain the catalyst precursor; The main dehydrogenation metal component precursor is selected from nitrates of group IIIA metal elements, the main hydrogenation metal component precursor is selected from nitrates of group VIII metal elements, and the auxiliary metal component precursor is selected from sulfates of group IIB metal elements. (2) The catalyst precursor is calcined to obtain the catalyst; The calcination operating conditions include a calcination temperature of 400-600℃.

4. The preparation method according to claim 3, wherein, The main dehydrogenation metal component precursor is gallium nitrate and / or indium nitrate; And / or, the main hydrogenation metal component precursor is one or more of cobalt nitrate, nickel nitrate, copper nitrate, and ruthenium nitrate; And / or, the auxiliary metal component precursor is zinc sulfate; And / or, the amounts of the main dehydrogenation metal component precursor, the main hydrogenation metal component precursor, and the auxiliary metal component precursor are such that the prepared catalyst contains 1-3 wt% of the main dehydrogenation metal component, 0.5-1.5 wt% of the main hydrogenation metal component, and 3-7 wt% of the auxiliary metal component.

5. The preparation method according to claim 3 or 4, wherein, The method for preparing the carrier includes: mixing a one-dimensional porous molecular sieve, a three-dimensional porous molecular sieve, a binder precursor, a molding aid, an adhesive, and water, extruding the mixture, and then calcining it to obtain the carrier.

6. The preparation method according to claim 5, wherein, The one-dimensional porous molecular sieve is one or more of MOR, ZSM-22, MCM-22, NU-87, ZSM-23, ZSM-48, and SAPO-41; And / or, the three-dimensional porous molecular sieve is one or more of ZSM-5, ZSM-11, β molecular sieve, and Y molecular sieve; And / or, the binder precursor is one or more of boehmite, silica sol, and alumina sol; And / or, the molding aid is one or more of guar gum powder, starch, and cellulose; And / or, the adhesive is one or more of nitric acid solution, acetic acid solution, and citric acid solution; And / or, the mass ratio of the one-dimensional porous molecular sieve to the three-dimensional porous molecular sieve is 1:0.1-2.5; And / or, the amount of the one-dimensional porous molecular sieve, the three-dimensional porous molecular sieve, and the binder precursor is such that the catalyst support prepared includes 60-95 wt% of composite molecular sieve and 5-40 wt% of binder. And / or, the calcination operating conditions include: a calcination temperature of 500-600℃ and a calcination time of 3-6h.

7. The preparation method according to claim 6, wherein, The amounts of the one-dimensional porous molecular sieve, the three-dimensional porous molecular sieve, and the binder precursor are such that the catalyst support prepared includes 70-90 wt% composite molecular sieve and 10-30 wt% binder.

8. The preparation method according to claim 3, wherein, The operation of the loading includes: first, impregnating the support in an impregnation solution containing a main dehydrogenation metal component precursor, a main hydrogenation metal component precursor, and a co-metal component precursor, and then aging it to obtain a catalyst precursor.

9. The preparation method according to claim 8, wherein, The impregnation is an equal-volume impregnation; And / or, the impregnation and aging are carried out in a closed device, wherein the impregnation is performed by shaking at room temperature for 5-20 minutes; and the aging is performed by standing at room temperature for 4-12 hours.

10. The preparation method according to claim 3, wherein, The calcination operating conditions include: calcination time of 3-6 hours.

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