A superacid carrier and preparation method thereof, isomerization catalyst and preparation method thereof

Abstract

The present invention relates to a superacid support and a preparation method thereof, an isomerization catalyst and a preparation method thereof, and relates to the technical field of catalysts. Based on the total dry weight of the superacid support, the superacid support comprises the following components in weight fractions: main component: 45% to 88%, first additive component: 5% to 20%, second additive component: 1% to 10%, third additive component: 1% to 10%, fourth additive component: 5 to 15%; the main component: ZrO2-SO4 2‑ ; the first additive component: AlPO4; the second additive component: SAPO-34 molecular sieve; the third additive component: phosphotungstic molybdic heteropolyacid; the fourth additive component: pseudo-boehmite. The superacid support provided by the present invention has the characteristics of stable support, strong acidity, large specific surface area, etc., can improve the activity and selectivity of the catalyst, and increase the yield of isomerization products.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts, and in particular to a superacid carrier and a preparation method thereof, an isomerization catalyst and a preparation method thereof. Background Art

[0002] At present, the general trend of global fuel cleaning is that gasoline is developing towards low sulfur, low olefins, low aromatics, and low benzene. Diesel is developing towards low sulfur, low aromatics (mainly polycyclic aromatics), low density and high cetane number. At present, the composition of gasoline in my country is mainly FCC (Fluid Catalytic Cracking, referred to as FCC) gasoline, followed by reformed gasoline, and finally MTBE (methyl tert-butyl ether) and alkylate. Due to the existence of olefins, high sulfur content and uneven octane distribution in gasoline components, it is necessary to adjust the components of gasoline. The isomerized oil component is an ideal blending component for clean gasoline because of its characteristics of no olefins, no aromatics, no sulfur, high octane number and low vapor pressure. In summary, the catalytic isomerization production process of light alkanes has broad application prospects in the future.

[0003] Isomerization reaction is an exothermic reaction, and low temperature is conducive to the forward reaction. If under low temperature conditions, it is necessary to improve the isomerization performance of the catalyst, that is, the acidity of the catalyst. The current isomerization process uses a bifunctional catalyst of metal and acid to improve the isomerization efficiency and suppress the occurrence of side reactions under hydrogen conditions. There are currently three main types of catalysts in industry. The first type is Pt-Al2O3-Cl low-temperature catalyst. This catalyst has strong acidity, and the reaction temperature of isomerization is low, and the yield of isoparaffin is high, but this type of catalyst needs to be continuously injected with chlorine during use to maintain the catalytic activity of the catalyst. The chlorine injection process causes corrosion of the device and environmental pollution, and this type of catalyst is very sensitive to the content of water and sulfur, and has strict requirements on the water and sulfur in the raw materials, basically requiring the raw materials to be free of water and sulfur. The second type is a modified medium-temperature catalyst with zeolite as the carrier. Due to the low acidity of zeolite materials, the isomerization reaction needs to be carried out at a higher temperature. Due to thermodynamic limitations, the catalytic activity of isomerization is low, but the advantages of this type of catalyst are: it has a certain tolerance to sulfur and water in the raw materials and will not corrode the reaction equipment. The third type is a sulfur-resistant catalyst with a solid superacid as a carrier. It has the advantages of strong acidity, no need for chlorine injection during the reaction process, safe operation, low equipment requirements, and low pollution, and has been widely used.

[0004] Japanese energy company applied for US patent US6326328 to disclose a SO4 2- / ZrO2 solid acid catalyst preparation method, the results show that the activity and isomerization performance of the catalyst are low.

[0005] US Patent No. 5157199 describes a catalyst of SO4 2- / ZrO2, used in the hydroisomerization reaction of C4-C6 straight-chain alkanes.

[0006] US Patent No. 3032599 and European Patent No. 0174836 also describe the use of SO4 2- A method for carrying out the hydroisomerization reaction of C4-C6 straight-chain alkanes using ZrO2 as a catalyst.

[0007] US Patent No. 6,080,904 describes a method for the hydroisomerization of linear alkanes, wherein the catalyst used is Pt-WO3 / ZrO2.

[0008] In summary, the emergence of solid superacid isomerization catalysts has gradually replaced Pt-Al2O3-Cl low-temperature catalysts and modified medium-temperature catalysts with zeolite as carriers due to its wide range of applications, water resistance and sulfur resistance. However, solid superacid catalysts need to be further improved due to their low isomerization performance. Summary of the invention

[0009] In order to solve the above problems, the present invention provides a superacid carrier and a preparation method thereof, an isomerization catalyst and a preparation method thereof.

[0010] In a first aspect, the present invention provides a superacid carrier, which comprises the following components in weight fractions based on the total weight of the superacid carrier on a dry basis: a main component: 45% to 88%, a first additional component: 5% to 20%, a second additional component: 1% to 10%, a third additional component: 1% to 10%, and a fourth additional component: 5% to 15%;

[0011] The main component: ZrO2-SO4 2- ;

[0012] The first added component: AlPO4;

[0013] The second added component: SAPO-34 molecular sieve;

[0014] The third additional component: phosphotungstomolybdic heteropoly acid;

[0015] The fourth additional component: pseudo-boehmite.

[0016] Furthermore, the specific surface area of ​​the superacid carrier is 5m 2 / g~300m 2 / g.

[0017] Furthermore, the pore size of the superacid carrier ranges from 5 nm to 40 nm.

[0018] In a second aspect, the present invention provides a method for preparing the superacid carrier according to any one of the first aspects, the preparation method comprising the following steps:

[0019] Adding the main component, the first additional component, the second additional component, the third additional component and the fourth additional component into a kneader in proportion and performing first kneading to obtain a mixed material;

[0020] adding nitric acid aqueous solution to the mixed material for a second kneading to obtain clinker;

[0021] The clinker is added into an extruder for extrusion molding, and then dried and roasted to obtain the super acid carrier.

[0022] Furthermore, the weight ratio of the mixture to the nitric acid aqueous solution is (90-92):(10-8); the weight percentage of nitric acid in the nitric acid aqueous solution is 35-40%; the first kneading working parameters include: kneading time 20-50 min; the second kneading working parameters include: kneading time 20-40 min; the drying working parameters include: drying at 80-120° C. for 6-12 hours; the roasting working parameters include: roasting at 400-800° C. for 4-16 hours.

[0023] In a third aspect, the present invention provides an isomerization catalyst, which comprises the following components in weight percentages based on the total weight of the isomerization catalyst on a dry basis: 0.01% to 5% of a core component, 0.1% to 10% of a first auxiliary agent, 0.1% to 10% of a second auxiliary agent, 0.1% to 10% of a third auxiliary agent, and the remainder is the superacid carrier described in any one of the first and second aspects;

[0024] The core component is one or a mixture of several elements selected from Pd, Pt, Ir and Rh;

[0025] The first auxiliary agent is one or a mixture of several rare earth metal elements;

[0026] The second auxiliary agent is one or a mixture of several alkaline earth elements;

[0027] The third auxiliary agent is one or a mixture of several elements from Group VIII.

[0028] Furthermore, the metal elements contained in the isomerization catalyst are Pd, Pt, Y, Ba and Co.

[0029] Furthermore, the Pd and the Pt are derived from one of the metal powders, oxides, halides, sulfates, nitrates, acetates and oxalates of Pd and Pt elements; the Y is derived from one of the oxides, halides, sulfates, nitrates, acetates and oxalates containing yttrium; the Ba is derived from one of the nitrates containing barium and the soluble compounds containing barium; the Co is derived from one of the cobalt nitrates, cobalt acetates, cobalt chlorides and soluble compounds.

[0030] In a fourth aspect, the present invention provides a method for preparing the isomerization catalyst according to any one of the third aspects, the preparation method comprising the following steps:

[0031] Obtaining the superacid carrier;

[0032] preparing an aqueous solution containing a core component, a first auxiliary agent, a second auxiliary agent and a third auxiliary agent;

[0033] The aqueous solution is impregnated on the superacid carrier by an impregnation method, and then dried at 80-120° C. for 6-12 hours, and then calcined at 450-800° C. for 4-16 hours to obtain the isomerization catalyst.

[0034] In a fifth aspect, the present invention provides a method for isomerizing an alkane, wherein the method uses the isomerization catalyst described in any one of the third aspect and the fourth aspect as the catalyst for isomerizing the alkane, and the operating parameters of the method for isomerizing the alkane include: the reactor is a fixed bed reactor, the reaction pressure is 1.0 to 4.0 MPa, the temperature is 160° C. to 260° C., and the mass space velocity is 1 h -1 ~3h -1 , hydrogen-to-oil molar ratio: 1.0-3.0; in terms of weight percentage, the raw material composition is: n-butane: 1%, isopentane: 24%, n-pentane: 26%, n-hexane: 9%, isohexane: 40%.

[0035] The above technical solution provided by the embodiment of the present invention has at least the following advantages compared with the prior art:

[0036] The embodiment of the present invention provides a superacid carrier and a preparation method thereof, an isomerization catalyst and a preparation method thereof. The superacid carrier provided by the present invention has the characteristics of stable carrier, strong acidity, large specific surface area, etc., which can improve the activity and selectivity of the catalyst and increase the yield of the isomerization product. Specifically:

[0037] 1. The composite metal catalyst prepared based on the modified superacid carrier of the present invention is suitable for a fixed bed process. By using a modified carrier, the activity and selectivity of the catalyst are improved, and the yield of the isomerization product is increased.

[0038] 2. The present invention uses a mixture of carriers, which are stable, highly acidic, and have a large specific surface area, which is beneficial to the main reaction of the catalyst and improves the isomerization yield.

[0039] 3. In the present invention, rare earth metals are used for modification, and the rare earth metal elements are combined with the carrier to inhibit the aggregation of precious metals and improve the heterogeneous performance of the catalyst. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0042] Figure 1 The present invention provides a flow chart of a method for preparing a superacid carrier. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0045] In a first aspect, the present invention provides a superacid carrier, which comprises the following components in weight fractions based on the total weight of the superacid carrier on a dry basis: a main component: 45% to 88%, a first additional component: 5% to 20%, a second additional component: 1% to 10%, a third additional component: 1% to 10%, and a fourth additional component: 5% to 15%;

[0046] The main component: ZrO2-SO4 2- ;

[0047] The first added component: AlPO4;

[0048] The second added component: SAPO-34 molecular sieve;

[0049] The third additional component: phosphotungstomolybdic heteropoly acid;

[0050] The fourth additional component: pseudo-boehmite.

[0051] The embodiment of the present invention provides a superacid carrier and a preparation method thereof, an isomerization catalyst and a preparation method thereof. The superacid carrier provided by the present invention has the characteristics of stable carrier, strong acidity, large specific surface area, etc., which can improve the activity and selectivity of the catalyst and increase the yield of the isomerization product. Specifically:

[0052] 1. The composite metal catalyst prepared based on the modified superacid carrier of the present invention is suitable for a fixed bed process. By using a modified carrier, the activity and selectivity of the catalyst are improved, and the yield of the isomerization product is increased.

[0053] 2. The present invention uses a mixture of carriers, which are stable, highly acidic, and have a large specific surface area, which is beneficial to the main reaction of the catalyst and improves the isomerization yield.

[0054] 3. In the present invention, rare earth metals are used for modification, and the rare earth metal elements are combined with the carrier to inhibit the aggregation of precious metals and improve the heterogeneous performance of the catalyst.

[0055] In some specific embodiments, the specific surface area of ​​the superacid carrier is 5 m 2 / g~300m 2 / g, preferably 100-200m 2 / g; the pore size range is 5nm to 40nm, preferably 8 to 15nm.

[0056] It should be noted that the component raw materials involved in the superacid carrier provided in the embodiments of the present invention, unless otherwise specified or specified, can be directly commercially available products.

[0057] In a second aspect, based on a general inventive concept, the present invention provides a method for preparing the superacid carrier according to any one of the first aspects, such as Figure 1 As shown, the preparation method comprises the following steps:

[0058] Adding the main component, the first additional component, the second additional component, the third additional component and the fourth additional component into a kneader in proportion and performing first kneading to obtain a mixed material;

[0059] adding nitric acid aqueous solution to the mixed material for a second kneading to obtain clinker;

[0060] The clinker is added into an extruder for extrusion molding, and then dried and roasted to obtain the super acid carrier.

[0061] In some specific embodiments, the weight ratio of the mixture to the nitric acid aqueous solution is (90-92):(10-8); the weight percentage of nitric acid in the nitric acid aqueous solution is 35-40%; the first kneading working parameters include: kneading time 20-50 min; the second kneading working parameters include: kneading time 20-40 min; the drying working parameters include: drying at 80-120°C for 6-12 hours; the roasting working parameters include: roasting at 400-800°C for 4-16 hours.

[0062] In a third aspect, the present invention provides an isomerization catalyst, which comprises the following components in weight percentages based on the total weight of the isomerization catalyst on a dry basis: 0.01% to 5% of a core component, 0.1% to 10% of a first auxiliary agent, 0.1% to 10% of a second auxiliary agent, 0.1% to 10% of a third auxiliary agent, and the remainder is the superacid carrier described in any one of the first and second aspects;

[0063] The core component is one or a mixture of several elements selected from Pd, Pt, Ir and Rh;

[0064] The first auxiliary agent is one or a mixture of several rare earth metal elements;

[0065] The second auxiliary agent is one or a mixture of several alkaline earth elements;

[0066] The third auxiliary agent is one or a mixture of several elements from Group VIII.

[0067] In some specific embodiments, the metal elements contained in the isomerization catalyst are Pd, Pt, Y, Ba and Co.

[0068] In some specific embodiments, the Pd and the Pt are derived from one of the metal powders, oxides, halides, sulfates, nitrates, acetates and oxalates of Pd and Pt elements; the Y is derived from one of the oxides, halides, sulfates, nitrates, acetates and oxalates containing yttrium; the Ba is derived from one of the nitrates containing barium and the soluble compounds containing barium; the Co is derived from one of the cobalt nitrates, cobalt acetates, cobalt chlorides and soluble compounds.

[0069] In a fourth aspect, the present invention provides a method for preparing the isomerization catalyst according to any one of the third aspects, the preparation method comprising the following steps:

[0070] Obtaining the superacid carrier;

[0071] preparing an aqueous solution containing a core component, a first auxiliary agent, a second auxiliary agent and a third auxiliary agent;

[0072] The aqueous solution is impregnated on the superacid carrier by an impregnation method, and then dried at 80-120° C. for 6-12 hours, and then calcined at 450-800° C. for 4-16 hours to obtain the isomerization catalyst.

[0073] In a fifth aspect, the present invention provides a method for isomerizing an alkane, wherein the method uses the isomerization catalyst described in any one of the third aspect and the fourth aspect as the catalyst for isomerizing the alkane, and the operating parameters of the method for isomerizing the alkane include: the reactor is a fixed bed reactor, the reaction pressure is 1.0 to 4.0 MPa, the temperature is 160° C. to 260° C., and the mass space velocity is 1 h -1 ~3h -1 , hydrogen-to-oil molar ratio: 1.0-3.0; in terms of weight percentage, the raw material composition is: n-butane: 1%, isopentane: 24%, n-pentane: 26%, n-hexane: 9%, isohexane: 40%.

[0074] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are intended only to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples that do not specify specific conditions are usually measured according to national standards. If there is no corresponding national standard, then the conditions recommended by the manufacturer are followed.

[0075] Example 1

[0076] This example provides an isomerization catalyst, and the preparation method thereof comprises the following steps:

[0077] Preparation of vector:

[0078] 700g of ZrO2-SO4 2- 100g AlPO4, 50g SAPO-34, 50g phosphotungstic heteropoly acid, 100g pseudo-boehmite were sequentially added to a kneader for 20 to 50min, 200g 35% nitric acid aqueous solution was added, and the kneading was continued for 20 to 40min. The kneaded clinker was put into an extruder for extrusion, and the extruded strip carrier was dried at 100°C for 8 hours, and then calcined at 550°C for 8 hours to obtain a catalyst carrier 1 with a specific surface area of ​​260m 2 / g, strength 128N / cm.

[0079] Preparation of catalyst:

[0080] Take 96.4g of carrier 1 and put it in a rotary evaporator, evacuate it for 2h, dissolve 0.42g of chloroplatinic acid, 0.17g of palladium dichloride, 0.57g of barium nitrate, 3.09g of yttrium nitrate, and 6.31g of cobalt nitrate in 60g of water to prepare a solution, and add the solution into the rotary evaporator with the carrier at 2r / min for 30min. Vacuum evaporate excess water, wait until the surface of the carrier is dry, take it out, and then dry it at 80℃ for 6h, and calcine it at 600℃ for 8h to obtain catalyst A.

[0081] Example 2

[0082] This example provides an isomerization catalyst, and the preparation method thereof comprises the following steps:

[0083] Take 96.4g of carrier 1 and put it in a rotary evaporator, evacuate it for 2h, dissolve 0.63g of chloroplatinic acid, 0.57g of barium nitrate, 3.09g of yttrium nitrate and 6.31g of cobalt nitrate in 60g of water to prepare a solution, and add the solution into the rotary evaporator with the carrier at 2r / min for 30min. Vacuum evaporate excess water, wait for the surface of the carrier to dry, take it out, and then dry it at 80℃ for 6h, and calcine it at 600℃ for 8h to obtain catalyst B.

[0084] Example 3

[0085] This example provides an isomerization catalyst, and the preparation method thereof comprises the following steps:

[0086] Preparation of vector:

[0087] 750g of ZrO2-SO4 2- 50g of powder, 50g of AlPO4, 50g of SAPO-34, 50g of phosphotungstic heteropoly acid, and 100g of pseudo-boehmite were sequentially added to a kneader for 20 to 50min, 180g of a 35% nitric acid aqueous solution was added, and the kneading was continued for 20 to 40min. The kneaded clinker was put into an extruder for extrusion, and the extruded strip carrier was dried at 100°C for 8 hours, and then calcined at 550°C for 8 hours to obtain a catalyst carrier 2 with a specific surface area of ​​230m 2 / g, strength 115N / cm.

[0088] Preparation of catalyst:

[0089] Take 96.4g of carrier 2 and put it in a rotary evaporator, evacuate it for 2h, dissolve 0.42g of chloroplatinic acid, 0.17g of palladium dichloride, 0.57g of barium nitrate, 3.09g of yttrium nitrate, and 6.31g of cobalt nitrate in 60g of water to prepare a solution, and add the solution into the rotary evaporator with the carrier at 2r / min for 30min. Vacuum evaporate excess water, wait until the surface of the carrier is dry, take it out, and then dry it at 80℃ for 6h, and calcine it at 600℃ for 8h to obtain catalyst C.

[0090] Example 4

[0091] This example provides an isomerization catalyst, and the preparation method thereof comprises the following steps:

[0092] Preparation of vector:

[0093] Take 96.4g of carrier 2 and put it in a rotary evaporator, evacuate it for 2h, dissolve 0.63g of chloroplatinic acid, 0.57g of barium nitrate, 3.09g of yttrium nitrate and 6.31g of cobalt nitrate in 60g of water to prepare a solution, and add the solution into the rotary evaporator with the carrier at 2r / min for 30min. Vacuum evaporate excess water, wait for the surface of the carrier to dry, take it out, and then dry it at 80℃ for 6h, and calcine it at 600℃ for 8h to obtain catalyst D.

[0094] Example 5

[0095] This example provides an isomerization catalyst, and the preparation method thereof comprises the following steps:

[0096] Preparation of vector:

[0097] 650g of ZrO2-SO4 2- The powder, 100gAlPO4, 50g SAPO-34, 50g phosphotungstic heteropoly acid, and 150g pseudo-boehmite were sequentially added to a kneader for 20 to 50 minutes, 220g of a 35% nitric acid aqueous solution was added, and the kneading was continued for 20 to 40 minutes. The kneaded clinker was put into an extruder for extrusion, and the extruded strip carrier was dried at 100°C for 8 hours, and then calcined at 550°C for 8 hours to obtain a catalyst carrier 3 with a specific surface area of ​​300m 2 / g, strength 135N / cm.

[0098] Preparation of catalyst:

[0099] Take 96.4g of carrier 3 and put it in a rotary evaporator, evacuate it for 2h, dissolve 0.42g of chloroplatinic acid, 0.17g of palladium dichloride, 0.57g of barium nitrate, 3.09g of yttrium nitrate, and 6.31g of cobalt nitrate in 60g of water to prepare a solution, and add the solution into the rotary evaporator with the carrier at 2r / min for 30min. Vacuum evaporate excess water, wait for the surface of the carrier to dry, take it out, and then dry it at 80℃ for 6h, and calcine it at 600℃ for 8h to obtain catalyst E.

[0100] Example 6

[0101] This example provides an isomerization catalyst, and the preparation method thereof comprises the following steps:

[0102] Take 96.4g of carrier 3 and put it in a rotary evaporator, evacuate it for 2h, dissolve 0.63g of chloroplatinic acid, 0.57g of barium nitrate, 3.09g of yttrium nitrate and 6.31g of cobalt nitrate in 60g of water to prepare a solution, and add the solution into the rotary evaporator with the carrier at 2r / min for 30min. Vacuum evaporate excess water, wait until the surface of the carrier is dry, take it out, and then dry it at 80℃ for 6h, and calcine it at 600℃ for 8h to obtain catalyst F.

[0103] Example 7

[0104] This example provides an isomerization catalyst, and the preparation method thereof comprises the following steps:

[0105] Preparation of vector:

[0106] 550g of ZrO2-SO4 2- The powder, 100g AlPO4, 100g SAPO-34, 50g phosphotungstic heteropoly acid, and 150g pseudo-boehmite were sequentially added to a kneader for 20 to 50min, 220g of a 35% nitric acid aqueous solution was added, and the kneading was continued for 20 to 40min. The kneaded clinker was put into an extruder for extrusion, and the extruded strip carrier was dried at 100°C for 8 hours, and then calcined at 550°C for 8 hours to obtain a catalyst carrier 4 with a specific surface area of ​​350m 2 / g, strength 150N / cm.

[0107] Preparation of catalyst:

[0108] Take 96.4g of carrier 4 and put it in a rotary evaporator, evacuate it for 2h, dissolve 0.42g of chloroplatinic acid, 0.17g of palladium dichloride, 0.57g of barium nitrate, 3.09g of yttrium nitrate, and 6.31g of cobalt nitrate in 60g of water to prepare a solution, and add the solution into the rotary evaporator with the carrier at 2r / min for 30min. Vacuum evaporate excess water, wait for the surface of the carrier to dry, take it out, and then dry it at 80℃ for 6h, and calcine it at 600℃ for 8h to obtain catalyst G.

[0109] Example 8

[0110] This example provides an isomerization catalyst, and the preparation method thereof comprises the following steps:

[0111] Take 96.4g of carrier 4 and put it in a rotary evaporator, evacuate it for 2h, dissolve 0.63g of chloroplatinic acid, 0.57g of barium nitrate, 3.09g of yttrium nitrate and 6.31g of cobalt nitrate in 60g of water to prepare a solution, and add the solution into the rotary evaporator with the carrier at 2r / min for 30min. Vacuum evaporate excess water, wait for the surface of the carrier to dry, take it out, and then dry it at 80℃ for 6h, and calcine it at 600℃ for 8h to obtain catalyst H.

[0112] Comparative Example 1

[0113] This example provides an isomerization catalyst, and the preparation method thereof comprises the following steps:

[0114] Preparation of vector:

[0115] 700g of ZrO2-SO4 2- The powder and 300g pseudo-boehmite are added into the kneader in sequence, and the kneading time is 20 to 50min. 200g 35% nitric acid aqueous solution is added, and the kneading is continued for 20 to 40min. The kneaded clinker is put into the extruder for extrusion. The extruded strip carrier is dried at 100℃ for 8 hours, and then calcined at 550℃ for 8 hours to obtain the catalyst carrier 5 with a specific surface area of ​​200m 2 / g, strength 100N / cm.

[0116] Preparation of catalyst:

[0117] Take 96.4g of carrier 5 and put it in a rotary evaporator, evacuate it for 2h, dissolve 0.42g of chloroplatinic acid, 0.17g of palladium dichloride, 0.57g of barium nitrate, 3.09g of yttrium nitrate, and 6.31g of cobalt nitrate in 60g of water to prepare a solution, and add the solution into the rotary evaporator with the carrier at 2r / min for 30min. Vacuum evaporate excess water, wait for the surface of the carrier to dry, take it out, and then dry it at 80℃ for 6 hours, and calcine it at 600℃ for 8 hours. It is worthy of catalyst comparison agent 1.

[0118] Comparative Example 2

[0119] This example provides an isomerization catalyst, and the preparation method thereof comprises the following steps:

[0120] Preparation of vector:

[0121] 1000g of pseudo-boehmite was added to the kneader in sequence, and the kneading time was 20 to 50min. 400g of 35% nitric acid aqueous solution was added, and the kneading was continued for 20 to 40min. The kneaded clinker was put into the extruder for extrusion. The extruded strip carrier was dried at 100°C for 8 hours, and then calcined at 550°C for 8 hours to obtain a catalyst carrier 6 with a specific surface area of ​​180m 2 / g, strength 80N / cm.

[0122] Preparation of catalyst:

[0123] Take 96.4g of carrier 1 and put it in a rotary evaporator, evacuate it for 2h, dissolve 0.42g of chloroplatinic acid, 0.17g of palladium dichloride, 0.57g of barium nitrate, 3.09g of yttrium nitrate, and 6.31g of cobalt nitrate in 60g of water to prepare a solution, and soak the solution in a rotary evaporator with the carrier at 2r / min for 30min. Vacuum evaporate excess water, wait until the surface of the carrier is dry, take it out, and then dry it at 80°C for 6 hours, and calcine it at 600°C for 8 hours to obtain catalyst contrast agent 2.

[0124] Comparative Example 3

[0125] This example provides an isomerization catalyst, and the preparation method thereof comprises the following steps:

[0126] Take 99.7g of carrier 3 and put it in a rotary evaporator, evacuate it for 2h, dissolve 0.42g of chloroplatinic acid and 0.17g of palladium dichloride in 60g of water to prepare a solution, soak the solution in the rotary evaporator with the carrier, rotate at 2r / min for 30min, evaporating excess water by vacuum, wait for the surface of the carrier to dry, take it out, and then dry it at 80℃ for 6h, and calcine it at 600℃ for 8h to obtain catalyst contrast agent 3.

[0127] Comparative Example 4

[0128] This example provides an isomerization catalyst, and the preparation method thereof comprises the following steps:

[0129] Take 99.7g of carrier 3 and put it into a rotary evaporator, evacuate it for 2h, dissolve 0.63g of chloroplatinic acid in 60g of water to prepare a solution, soak the solution in the rotary evaporator with the carrier, rotate at 2r / min for 30min, evaporating excess water by vacuum, wait for the surface of the carrier to dry, take it out, and then dry it at 80℃ for 6h, and calcine it at 600℃ for 8h to obtain catalyst contrast agent 4.

[0130] Test Case

[0131] The isomerization catalyst obtained in the examples and comparative examples was used in a fixed bed reactor at a reaction pressure of 2.5 MPa, a temperature of 180°C, and a mass space velocity of 1.5 h -1 , hydrogen-to-oil molar ratio: 2.0, raw material composition: n-butane: 1%, isopentane: 24%, n-pentane: 26%, n-hexane: 9%, isohexane: 40%.

[0132] The physicochemical indicators of the catalyst are shown in Table 1, and the isomerization performance test data of the catalyst are shown in Table 2.

[0133] Table 1

[0134]

[0135]

[0136] Table 2

[0137] Catalyst name C5 isomerization rate, % C6 isomerization rate, % Catalyst A 43.2％ 67.3％ Catalyst B 40.8％ 59.9％ Catalyst C 43.1％ 68.0％ Catalyst D 42.8％ 70.4％ Catalyst E 60.3％ 80.8％ Catalyst F 59.4％ 81.3％ Catalyst G 45.7％ 69.1％ Catalyst H 42.4％ 68.3％ Comparative Example 1 21.7％ 15.6％ Comparative Example 2 16.8％ 10.5％ Comparative Example 3 50.2％ 66.1％ Comparative Example 4 55.7％ 61.5％

[0138] It can be seen from Table 1 and Table 2 above that the composite metal catalyst prepared using a modified superacid carrier can improve the activity and selectivity of the catalyst and increase the yield of isomerization products. Using a variety of mixed carriers, the carrier is stable, has strong acidity, and has a large specific surface area, which is conducive to the main reaction of the catalyst and improves the isomerization yield. In the present invention, rare earth and transition metals are used for modification, and the rare earth metal elements are combined with the carrier to inhibit the aggregation of precious metals and improve the isomerization performance of the catalyst.

[0139] Various embodiments of the present invention may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present invention; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0140] In the present invention, in the absence of contrary instructions, the directional words used, such as "upper" and "lower", are specifically the directions of the drawings in the accompanying drawings. In addition, in the description of the specification of the present invention, the terms "including", "comprising", etc. refer to "including but not limited to". In this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. In this article, "and / or" describes the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. Wherein A, B can be singular or plural. In this article, "at least one" refers to one or more, and "plural" refers to two or more. "At least one", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of singular or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or plural, respectively.

[0141] The foregoing is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. An isomerization catalyst, characterized in that Based on the total weight of the isomerization catalyst on a dry basis, the isomerization catalyst comprises the following components in weight percentage: 0.01% to 5% of a core component, 0.1% to 10% of a first auxiliary agent, 0.1% to 10% of a second auxiliary agent, 0.1% to 10% of a third auxiliary agent, and the balance being a superacid carrier; The core component is one or a mixture of several elements selected from Pd, Pt, Ir and Rh; The first auxiliary agent is one or a mixture of several rare earth metal elements; The second auxiliary agent is one or a mixture of several alkaline earth elements; The third auxiliary agent is one of the elements of Group VIII; the Group VIII element is Co; Based on the total weight of the superacid carrier on a dry basis, the superacid carrier comprises the following components in weight fractions: a main component: 45% to 88%, a first additional component: 5% to 20%, a second additional component: 1% to 10%, a third additional component: 1% to 10%, and a fourth additional component: 5% to 15%; The main component: ZrO2-SO4 2- ; The first added component: AlPO4; The second added component: SAPO-34 molecular sieve; The third additional component: phosphotungstomolybdic heteropoly acid; The fourth additional component: pseudo-boehmite; The preparation method comprises the following steps: Adding the main component, the first additional component, the second additional component, the third additional component and the fourth additional component into a kneader in proportion and performing first kneading to obtain a mixed material; adding nitric acid aqueous solution to the mixed material for a second kneading to obtain clinker; The clinker is added into an extruder for extrusion molding, and then dried and roasted to obtain the super acid carrier; The weight ratio of the mixed material to the nitric acid aqueous solution is (90-92):(10-8); the weight percentage of nitric acid in the nitric acid aqueous solution is 35-40%; the working parameters of the first kneading include: kneading time of 20-50 minutes; the working parameters of the second kneading include: kneading time of 20-40 minutes; the working parameters of the drying include: drying at 80-120°C for 6-12 hours; the working parameters of the roasting include: roasting at 400-800°C for 4-16 hours.

2. The isomerization catalyst according to claim 1, characterized in that The metal elements contained in the isomerization catalyst are Pd, Pt, Y, Ba and Co.

3. The isomerization catalyst according to claim 2, characterized in that The Pd and Pt are derived from one of the metal powders, oxides, halides, sulfates, nitrates, acetates and oxalates of Pd and Pt elements; the Y is derived from one of the oxides, halides, sulfates, nitrates, acetates and oxalates containing yttrium; the Ba is derived from one of the nitrates containing barium and the soluble compounds containing barium; the Co is derived from one of the cobalt nitrates, cobalt acetates, cobalt chlorides and soluble compounds.

4. A method for preparing the isomerization catalyst according to any one of claims 1 to 3, characterized in that: The preparation method comprises the following steps: Obtaining the superacid carrier; preparing an aqueous solution containing a core component, a first auxiliary agent, a second auxiliary agent and a third auxiliary agent; The aqueous solution is impregnated on the superacid carrier by an impregnation method, and then dried at 80-120° C. for 6-12 hours, and then calcined at 450-800° C. for 4-16 hours to obtain the isomerization catalyst.

5. A method for isomerizing alkanes, characterized in that: The method uses the isomerization catalyst described in any one of claims 1 to 4 as a catalyst for alkane isomerization. The working parameters of the alkane isomerization method include: the reactor is a fixed bed reactor, the reaction pressure is 1.0 to 4.0 MPa, the temperature is 160° C. to 260° C., and the mass space velocity is 1 h -1 ~3h -1 , hydrogen-to-oil molar ratio: 1.0-3.0; in terms of weight percentage, the raw material composition is: n-butane: 1%, isopentane: 24%, n-pentane: 26%, n-hexane: 9%, isohexane: 40%.

Images