Sulfurized dehydrogenation catalyst, preparation method and application thereof, and propane dehydrogenation method

Abstract

The invention provides a sulfurized dehydrogenation catalyst, a preparation method and application thereof and a propane dehydrogenation method, the preparation method comprises the following steps: (1) contacting a carrier with a first sulfide for first sulfuration to obtain a sulfurized carrier; (2) carrying out contact loading on the sulfurized carrier and a dehydrogenation active component source solution to obtain a loaded dehydrogenation catalyst; and (3) contacting the supported dehydrogenation catalyst with a second sulfide to carry out second vulcanization so as to obtain the vulcanized dehydrogenation catalyst. The dehydrogenation catalyst is used for dehydrogenation, especially alkane dehydrogenation such as propane dehydrogenation reaction, has good selectivity, can improve propylene selectivity by more than 3%, and has good industrial prospect.

Description

Technical Field

[0001] The invention relates to a sulfided dehydrogenation catalyst, a preparation method and application thereof, and a propane dehydrogenation method. Background Art

[0002] As one of the main ways to obtain propylene, the catalytic dehydrogenation of propane to propylene has developed rapidly in the past decade. However, this reaction is an endothermic reaction with an increase in the number of molecules. It needs to be carried out at high temperature and low pressure, and the process is limited by thermodynamic equilibrium. However, excessively high reaction temperatures intensify propane cracking side reactions and deep dehydrogenation, resulting in reduced propylene selectivity. At the same time, it leads to a rapid increase in carbon accumulation on the catalyst surface, which reduces the catalyst's reaction activity and causes it to be temporarily deactivated. Especially for dehydrogenation catalysts that require frequent regeneration, the development of catalysts with resistance to carbon deposition, high propylene selectivity and high dehydrogenation stability has become the key.

[0003] Chinese patent application CN201210427704.8 reports a method for preparing a sulfurized dehydrogenation catalyst. The inventor preloads the sulfur in the passivator into the carrier at one time, so that it has more contact opportunities with the active metal at the microscopic scale, and has a better sulfurization effect during the reduction process, inhibiting carbon deposition and increasing catalyst stability. The sulfurizing agent used in this technology is one of sodium sulfide and potassium sulfide or a mixture of the two, and the impregnated active component is the Pt element.

[0004] Chinese patent application CN202211075683.8 discloses a catalyst, preparation method and application of propane dehydrogenation to propylene under sulfur-containing conditions, specifically discloses a catalyst, preparation method and application of propane dehydrogenation to propylene under sulfur-containing conditions, wherein the catalyst is placed in a fixed bed continuous flow tubular reactor, H2 is introduced, the H2 flow rate is adjusted to 5000 mL / h, and propane containing sulfide gas is introduced into the reactor at a flow rate of 10000 mL / h, the reaction is maintained at 1 atm, and the temperature is 600°C for dehydrogenation reaction to prepare propylene, wherein the sulfide gas is H2S or dimethyl disulfide, and the concentration of the sulfide is 50 to 100×10 -6 g / m 3 The catalyst used is alumina as a carrier, and Pt, alkali metal and active components are loaded on the carrier surface, wherein the active components are one or more of Ir, Re and Ru. A preparation method of the catalyst is also disclosed, which specifically includes the steps of material preparation, loading, drying and calcination, and points out that the catalyst can effectively avoid the problem of poisoning caused by sulfide in the raw material when preparing propylene, thereby ensuring the activity of the catalyst. The disadvantage is that in order to improve the performance of the catalyst, sulfide and propane raw gas are introduced into the reactor together.

[0005] Chinese patent application CN201510868382.4 discloses a preparation method of a catalyst for propane dehydrogenation to propylene and a catalyst thereof, specifically discloses a preparation method of a catalyst for propane dehydrogenation to propylene, using a bimetallic combination of a metal of a Group IV element and a metal of a Group III element as an auxiliary agent, a metal of a platinum group element as an active component of catalyst dehydrogenation, and a molded alumina as a carrier. The preparation process of the catalyst includes: introducing the Sn-Al auxiliary agent into the alumina carrier by a co-impregnation method, so that Sn is more evenly dispersed in the carrier at the atomic level, and at the same time enhancing the interaction between Sn and the alumina carrier; then impregnating the dehydrogenation active component on the Sn-Al-containing alumina carrier to increase the interaction between the metal-auxiliary agent-carrier; finally, drying, roasting, dechlorination, impregnation with an alkali metal auxiliary agent, impregnation with dilute hydrochloric acid and sulfidation are performed to finally obtain a dehydrogenation catalyst. It is pointed out that the catalyst can be used for the dehydrogenation reaction of low-carbon alkanes, especially the dehydrogenation reaction of propane, and has the advantages of high activity, good selectivity, good catalyst stability, etc., especially the selectivity and stability are significantly improved. Its disadvantage is that the sulfidation treatment is carried out as the last step, which leads to problems such as easy loss of sulfide.

[0006] Chinese patent application CN200910011771.X, a method for preparing a sulfided dehydrogenation catalyst discloses a method for preparing a sulfided dehydrogenation catalyst, first preparing an alumina carrier containing La and Sn, then impregnating the dehydrogenation active component, after steam dechlorination treatment, adding a sulfur-containing compound (the sulfur-containing compound can be one or more of K2S, Na2S or (NH4)2S) and drying to obtain a final dehydrogenation catalyst. The dehydrogenation catalyst prepared by the method of the present invention has the advantages of good activity stability, long catalyst service life, good regeneration performance, etc. when used for propane dehydrogenation, and is most suitable for use in the process of propane dehydrogenation to propylene. Its disadvantage is that the sulfide is introduced by impregnation, which will cause uneven distribution and easy loss.

[0007] Chinese patent application CN201910638304.3 discloses a carbon deposit inhibitor, which mainly solves the problem of carbon deposit reducing propylene conversion rate and selectivity during dehydrogenation of low-carbon alkanes in the prior art; the carbon deposit inhibitor, in parts by weight, includes the following components: a) 50 to 80 parts of a sulfiding agent; b) 5 to 8 parts of a dispersant; c) 1 to 7 parts of an antioxidant; d) 5 to 44 parts of a solvent, and the sulfur content in the carbon deposit inhibitor is 17% to 55% based on the total weight of the carbon deposit inhibitor; it solves the problem of propylene conversion rate and selectivity well, and can be used for industrial applications of dehydrogenation of low-carbon alkanes. Its disadvantage is that there are many types of carbon deposit inhibitors and the treatment process is complicated. Summary of the invention

[0008] The purpose of the present invention is to overcome the problems of more carbon deposits and lower selectivity in the prior art, and to provide a sulfided dehydrogenation catalyst, a preparation method and application thereof, and a propane dehydrogenation method.

[0009] In view of the defects of the prior art, the present invention proposes for the first time that a sulfiding agent is introduced to carry out sulfidation after the carrier is sulfided and the active components are loaded on the catalyst, thereby improving the catalyst's ability to resist carbon deposition and achieving significant results.

[0010] In order to achieve the above object, the present invention provides a method for preparing a sulfided dehydrogenation catalyst, which comprises:

[0011] (1) contacting the carrier with a first sulfide to perform a first sulfidation to obtain a sulfided carrier;

[0012] (2) contacting the sulfided carrier with a dehydrogenation active component source solution to obtain a supported dehydrogenation catalyst;

[0013] (3) contacting the supported dehydrogenation catalyst with a second sulfide to perform a second sulfidation to obtain a sulfided dehydrogenation catalyst.

[0014] The second aspect of the present invention provides a sulfided dehydrogenation catalyst prepared by the preparation method of the present invention.

[0015] The third aspect of the present invention provides the use of a sulfided dehydrogenation catalyst in the dehydrogenation of alkanes to produce olefins.

[0016] The present invention provides a propane dehydrogenation method, which comprises: in the presence of a catalyst, subjecting propane to a dehydrogenation reaction, wherein the catalyst comprises the sulfided dehydrogenation catalyst of the present invention,

[0017] The dehydrogenation catalyst of the present invention is used for dehydrogenation, especially alkane dehydrogenation such as propane dehydrogenation reaction, and has good selectivity, for example, it can improve propylene selectivity by more than 3%, and has good industrial prospects.

[0018] Compared with the catalyst which is not subjected to the sulfidation treatment according to the method of the present invention, the sulfided dehydrogenation catalyst of the present invention can significantly reduce the occurrence of cracking reaction in the dehydrogenation process and improve the dehydrogenation selectivity by more than 3%. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is the XPS spectrum of the surface S of the catalyst sample prepared in Example 1 of the present invention.

[0020] Figure 2 It is the XPS spectrum of the surface S of the catalyst sample prepared in Comparative Example 1 of the present invention.

[0021] Figure 3 It is the XPS spectrum of the surface S of the catalyst sample prepared in Comparative Example 2 of the present invention.

[0022] Figure 4 It is the XPS spectrum of the surface S of the catalyst sample prepared in Comparative Example 3 of the present invention. DETAILED DESCRIPTION

[0023] The endpoints and any values ​​of the ranges disclosed in this article 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 each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0024] The present invention provides a method for preparing a sulfided dehydrogenation catalyst, the preparation method comprising:

[0025] (1) contacting the carrier with a first sulfide to perform a first sulfidation to obtain a sulfided carrier;

[0026] (2) contacting the sulfided carrier with a dehydrogenation active component source solution to obtain a supported dehydrogenation catalyst;

[0027] (3) contacting the supported dehydrogenation catalyst with a second sulfide for a second sulfidation to obtain a sulfided dehydrogenation catalyst. The sulfided dehydrogenation catalyst obtained by the above method of the present invention can significantly reduce the occurrence of cracking reactions during the dehydrogenation process, and improve the dehydrogenation selectivity by more than 3%, compared with the catalyst not sulfided according to the method of the present invention.

[0028] In the present invention, in step (2), there are no special requirements for the contact loading method, drying after loading, and calcination conditions. For example, it is generally dried at 80-120° C. for 3-10 hours and calcined at 500-700° C. for 1-5 hours.

[0029] In the present invention, according to a preferred embodiment of the present invention, the amount of the first sulfide added is 30-90% of the total sulfur amount calculated as sulfur element, preferably 35-80%; the use of the aforementioned preferred embodiment can further improve the dehydrogenation selectivity.

[0030] In the present invention, the difference in the names of the first sulfide and the second sulfide is mainly used for distinguishing and explaining, and does not mean that the two must be different material selections. The present invention has no special requirements on the material types of the first sulfide and the second sulfide, and commonly used sulfide types can be used in the present invention. For the present invention, the exemplary description is given, but the scope of the present invention is not limited thereby. The first sulfide and the second sulfide are preferably each selected from an inorganic sulfide and / or an organic sulfide.

[0031] In the present invention, the inorganic sulfide has a wide range of optional types, which are exemplified below but do not limit the scope of the present invention. According to one embodiment of the present invention, the inorganic sulfide is selected from one or more of Na2S, K2S, and (NH4)2S.

[0032] In the present invention, the types of organic sulfides can be selected from a wide range, which are exemplified below, but the scope of the present invention is not limited thereto. According to one embodiment of the present invention, the organic sulfide is selected from alkyl sulfides, more preferably alkyl sulfides, more preferably one or more of methyl ethyl sulfide, dimethyl sulfide, and diethyl sulfide.

[0033] According to a preferred embodiment of the present invention, the first sulfide is preferably different from the second sulfide, wherein the first sulfide is selected from inorganic sulfides; the second sulfide is selected from organic sulfides, particularly preferably alkyl sulfides, more preferably one or more of methyl ethyl sulfide, dimethyl sulfide, and diethyl sulfide. The use of the aforementioned preferred sulfides can improve the dehydrogenation selectivity.

[0034] According to a preferred embodiment of the present invention, the second sulfide is preferably selected from a mixture of methyl ethyl sulfide and diethyl sulfide, and more preferably the molar ratio of the two calculated as sulfur element is 0.1-10:1, for example, 0.1:1, 0.4:1, 0.5:1, 1:1, 2.5:1, 5:1, 10:1. The molar ratio of 1:1 is used as an example in the embodiments of the present invention, but the scope of the present invention is not limited thereby.

[0035] In the present invention, in step (1), the conditions for the first sulfidation can be selected in a wide range, for example including but not limited to: the amount of the first sulfide added is 0.1-5% by weight of the carrier in terms of sulfur element, preferably 0.5-3%.

[0036] In the present invention, in step (1), the conditions for the first vulcanization can be selected in a wide range, for example including but not limited to: the first sulfide and water form an aqueous solution which is contacted with a carrier to perform the first vulcanization, and the concentration of the aqueous solution is 3-15wt%.

[0037] In the present invention, there is no special requirement for the contact method in step (1). According to one embodiment of the present invention, the contact method is an immersion contact method.

[0038] The present invention also includes drying after contacting to complete the first vulcanization. There is no special requirement for the drying conditions, and common drying conditions can be used in the present invention, which will not be described in detail herein. For example, the drying temperature is 140-160° C. and the drying time is 10-20 hours.

[0039] In the present invention, in step (3), the conditions for the second vulcanization can be selected in a wide range, for example including but not limited to: the amount of the second sulfide added is 10-70% of the total sulfur content calculated as sulfur element, preferably 20-65%.

[0040] In the present invention, in step (3), the conditions for the second sulfurization can be selected in a wide range, for example, including but not limited to: the second sulfide and the solvent form a solution and contact the supported dehydrogenation catalyst to perform the second sulfurization, the concentration of the solution is 10-20wt%, and the solvent can be selected in a wide range, for example, anhydrous ethanol.

[0041] In the present invention, there is no special requirement for the contact method in step (3). According to one embodiment of the present invention, the contact method is an immersion contact method.

[0042] The present invention also includes drying and calcining after contacting to complete the second vulcanization. There are no special requirements for the drying and calcining conditions, and the commonly used drying and calcining conditions can be used in the present invention, which will not be described in detail herein. For example, the drying temperature is 140-160° C., the time is 10-20 hours, and the calcining temperature is 500-600° C., and the time is 2-4 hours.

[0043] The present invention has no special requirements for the carrier, and any common carrier used in the method of the present invention to prepare the catalyst can achieve the purpose of the present invention. According to one embodiment of the present invention, the carrier contains Group IA and / or Group IVB elements; and a carrier base.

[0044] There are no special requirements for the composition, content and preparation method of the carrier, which are exemplified below, but the scope of the present invention is not limited thereby.

[0045] According to one embodiment of the present invention, preferably, the content of the Group IA element, calculated as the element, accounts for 0.3-3% of the weight of the carrier.

[0046] According to one embodiment of the present invention, the content of the Group IVB element, calculated as the element, accounts for 0.3-2% of the weight of the carrier.

[0047] According to one embodiment of the present invention, more preferably, the Group IA element is selected from one or more of Na, K, Rb, and Cs, preferably at least one of Na and K.

[0048] According to one embodiment of the present invention, more preferably, the Group IVB element is Ti and / or Zr, preferably Zr.

[0049] According to one embodiment of the present invention, more preferably, more preferably, the Group IA and / or Group IVB elements are introduced into the carrier base by impregnation method to form the carrier, and there are no special requirements for the impregnation loading method, drying after loading, and calcination conditions. For example, it is generally dried at 80-120°C for 3-10h and calcined at 500-700°C for 1-5h.

[0050] In the present invention, there is no special requirement for the type and content of the dehydrogenation active component elements. The following is an exemplary description, but the scope of the present invention is not limited thereby.

[0051] According to a preferred embodiment of the present invention, the dehydrogenation active component element is selected from the metal elements of Group VIB, preferably one or more of Cr, Mo, and W, and more preferably Cr.

[0052] According to a preferred embodiment of the present invention, the dehydrogenation active component element, calculated on the basis of the total weight of the catalyst, has a content of 10 to 25% of the dehydrogenation active component element.

[0053] In the present invention, there is no special requirement for the type of the carrier base, which is described below for exemplary purposes, but does not limit the scope of the present invention.

[0054] According to a preferred embodiment of the present invention, the carrier substrate is selected from aluminum oxide and / or silicon oxide.

[0055] The present invention has no special requirements on the morphology of the carrier, and the carrier base material can be powder or shaped particles.

[0056] According to a preferred embodiment of the present invention, the carrier base is preferably obtained by using a carrier precursor through a precipitation method, and optionally forming it.

[0057] According to a preferred embodiment of the present invention, more preferably, the carrier precursor is one or more of pseudo-boehmite, boehmite, alumina sol, alumina gel, and silica sol.

[0058] In the present invention, alumina is used as a carrier base material in the examples for illustrative purposes, and there is no special requirement for its preparation method. In the examples, it is prepared according to the following steps:

[0059] Weigh 4000g of aluminum nitrate nonahydrate and dissolve it in 1800g of deionized water to form a solution. Dissolve 64g of polyethylene glycol in the above solution. Pump in 40wt% ammonia solution. Measure the pH value of the system with a pH meter. The end point pH is about 5-6. Continue to stir the solution for 1h, let it stand for 12h, then filter it, wash it with deionized water 3 times, and put it in a 120℃ oven to dry for 12h to obtain the desired alumina precursor.

[0060] After the carrier base alumina precursor is prepared, it is shaped as needed. In the embodiment, it is prepared according to the following steps:

[0061] Weigh 400g of the above-mentioned alumina precursor and 12g of sesbania powder, mix them at room temperature for 10 minutes, then add 120g of an aqueous solution of 40wt% nitric acid, continue kneading for 15 minutes to form a dough, and extrude it into a dough. The molded sample is left for 8 hours, dried in an oven at 120°C for 4 hours, and calcined at 600°C for 6 hours to obtain calcined alumina I.

[0062] In the present invention, washing is performed as needed before each drying step, which is a technique well known to those skilled in the art.

[0063] The present invention provides a sulfided dehydrogenation catalyst prepared by the preparation method of the present invention. The sulfided dehydrogenation catalyst comprises, calculated as oxides and based on the total weight of the catalyst, 0.5-5% of sulfur, 10-25% of a dehydrogenation active component, 0.3-3% of a Group IA element additive and / or 0.3-2% of a Group IVB element additive.

[0064] The present invention provides the use of a sulfided dehydrogenation catalyst in the dehydrogenation of alkanes to prepare olefins. Preferably, the alkanes are one or more C2-C6 alkanes.

[0065] The catalyst of the present invention is particularly suitable for a propane dehydrogenation method, which comprises: subjecting propane to a dehydrogenation reaction in the presence of a catalyst, wherein the catalyst comprises the sulfided dehydrogenation catalyst of the present invention.

[0066] In the present invention, there is no special requirement for the conditions of the dehydrogenation reaction, which are exemplified below, but the scope of the present invention is not limited thereby.

[0067] According to a preferred embodiment of the present invention, preferably, the conditions for the dehydrogenation reaction include: a reaction temperature of 600-650°C, a reaction pressure of 0.05-0.2 MPa, and a propane mass space velocity of 0.4-1.0 h -1 .

[0068] The present invention will be described in detail by way of examples. In the following examples, the gas components and compositions at the reactor outlet were measured by means of an Agilent 7890 chromatograph; the inorganic sulfiding agent in the sulfiding agent was from China Pharmaceutical Group, and the organic sulfiding agent was a commercial product from Aldrich.

[0069] The XPS spectrum test includes: using the X-ray photoelectron spectrometer (XPS) AXIS Ultra DLD of Kratos Analytical Ltd, with a Mg / Al dual anode X-ray source, a hemispherical energy analyzer, and a 128-channel delay line detector. The analysis chamber is ultra-high vacuum, with a minimum pressure of <7×10 -8 Pa, from a few seconds to tens of seconds to obtain μm-level high-resolution element image, chemical state and other information, this is a technology well known to those skilled in the art and will not be described in detail.

[0070] In the embodiments and comparative examples of the present invention,

[0071] Conversion rate of propane (%) = (mass of propane in reactants - mass of propane in reaction products) ÷ mass of propane in reactants × 100%;

[0072] Selectivity of propylene (%) = actual yield of propylene / theoretical yield of propylene × 100%, by mass.

[0073] In the examples and comparative examples of the present invention, the analysis of the gas composition in the propane dehydrogenation reaction was performed on a gas chromatograph model 7890A purchased from Agilent Technologies.

[0074] Example 1

[0075] I: Weigh 4000g of aluminum nitrate nonahydrate and dissolve it in 1800g of deionized water to form a solution. Fully dissolve 64g of polyethylene glycol (average molecular weight 400, the same as the other embodiments and comparative examples) in the above solution, pump in 40wt% ammonia solution, measure the pH value of the system with a pH meter, and the end point pH is about 5-6. Continue to stir the solution for 1h, let it stand for 12h, then filter it by suction, wash it with deionized water 3 times, and put it in a 120℃ oven to dry for 12h to obtain the desired alumina precursor.

[0076] II: Weigh 400g of the above aluminum oxide precursor and 12g of sesbania powder, mix them at room temperature for 10 minutes, then add 120g of an aqueous solution of 40wt% nitric acid, continue kneading for 15 minutes to form a dough, and extrude it into a dough. The molded sample is left for 8 hours, dried in an oven at 120°C for 4 hours, and calcined at 600°C for 6 hours to obtain calcined aluminum oxide I.

[0077] III: First measure the water absorption rate of alumina I, weigh 1.6 grams of sodium nitrate and 1.9 grams of zirconium nitrate, dissolve them in 30 grams of water, then weigh 100 grams of alumina I, place them in the solution for equal volume immersion to ensure full contact, then dry at 120°C for 4 hours, and calcine at 600°C for 2 hours to obtain alumina II.

[0078] IV: Weigh 2.0 g of sodium sulfide, dissolve it in 20 g of deionized water, then add it to alumina II and bake it at 150° C. for 12 hours to obtain the first sulfur-treated sample.

[0079] V: Weigh 79 grams of chromium nitrate, dissolve it in 30 grams of deionized water, add it to the first sulfur-treated sample, dry it at 120°C for 4 hours, and calcine it at 600°C for 2 hours to obtain a sample loaded with active components.

[0080] VI: Weigh 1.0 g of dimethyl sulfide, dissolve it in 10 g of anhydrous ethanol, and then add it to the sample loaded with the active component. Then, bake it at 150° C. for 12 hours and calcine it at 550° C. for 3 hours to obtain the final sample.

[0081] Figure 1 is the XPS spectrum of the catalyst sample surface S prepared in Example 1 of the present invention, Figure 1 It can be seen that there is an XPS spectrum of S2p on the surface of the dehydrogenation catalyst.

[0082] Dehydrogenation reaction, the following examples are the same as the comparative examples:

[0083] Weigh 10 grams of dehydrogenation catalyst and add it to the isothermal fixed bed reactor, where the reactor is a quartz tube with an inner diameter of 20 mm and an outer diameter of 30 mm, and is 600 mm long. The pure propane gas is regulated by a mass flow meter and enters the preheating zone for preheating, and then enters the reaction zone. The heating section and the reaction section of the reactor are heated by electric heating wires to reach 600°C, the reaction pressure is 0.1 MPa, and the propane mass space velocity is 0.7 h -1 After 1 hour of reaction, the gas passes through the condenser and enters the gas chromatography to analyze its composition. The dehydrogenation performance of the sample is shown in Table 1.

[0084] Example 2

[0085] I: Weigh 4000g aluminum nitrate nonahydrate and dissolve it in 1800g deionized water to form a solution. Dissolve 64g polyethylene glycol in the above solution. Pump in 40wt% ammonia solution. Measure the pH value of the system with a pH meter. The end point pH is about 5-6. Continue to stir the solution for 1h, let it stand for 12h, then filter it, wash it with deionized water 3 times, and put it in a 120℃ oven to dry for 12h to obtain the desired alumina precursor.

[0086] II: Weigh 400g of the above aluminum oxide precursor and 12g of sesbania powder, mix them at room temperature for 10 minutes, then add 120g of an aqueous solution of 40wt% nitric acid, continue kneading for 15 minutes to form a dough, and extrude it into a dough. The molded sample is left for 8 hours, dried in an oven at 120°C for 4 hours, and calcined at 600°C for 6 hours to obtain calcined aluminum oxide I.

[0087] III: First measure the water absorption rate of alumina I, weigh 1.6 grams of sodium nitrate and 1.9 grams of zirconium nitrate, dissolve them in 30 grams of water, then weigh 100 grams of alumina I, place them in the solution to allow full contact, then dry at 120°C for 4 hours, and calcine at 600°C for 2 hours to obtain alumina II.

[0088] IV: Weigh 2.3 g of sodium sulfide, dissolve it in 20 g of deionized water, then add it to alumina II and bake it at 150° C. for 12 hours to obtain the first sulfur-treated sample.

[0089] V: Weigh 79 grams of chromium nitrate, dissolve it in 30 grams of deionized water, add it to the first sulfur-treated sample, dry it at 120°C for 4 hours, and calcine it at 600°C for 2 hours to obtain a sample loaded with active components.

[0090] VI: Weigh 0.6 g of dimethyl sulfide, dissolve it in 10 g of anhydrous ethanol, and then add it to the sample loaded with active components. Then bake it at 150°C for 12 hours and calcine it at 550°C for 3 hours to obtain the final sample. The XPS spectrum is the same as Figure 1 Similarly, the dehydrogenation performance of the samples is shown in Table 1.

[0091] Example 3

[0092] I: Weigh 4000g aluminum nitrate nonahydrate and dissolve it in 1800g deionized water to form a solution. Dissolve 64g polyethylene glycol in the above solution. Pump in 40wt% ammonia solution. Measure the pH value of the system with a pH meter. The end point pH is about 5-6. Continue to stir the solution for 1h, let it stand for 12h, then filter it, wash it with deionized water 3 times, and put it in a 120℃ oven to dry for 12h to obtain the desired alumina precursor.

[0093] II: Weigh 400g of the above aluminum oxide precursor and 12g of sesbania powder, mix them at room temperature for 10 minutes, then add 120g of an aqueous solution of 40wt% nitric acid, continue kneading for 15 minutes to form a dough, and extrude it into a dough. The molded sample is left for 8 hours, dried in an oven at 120°C for 4 hours, and calcined at 600°C for 6 hours to obtain calcined aluminum oxide I.

[0094] III: First measure the water absorption rate of alumina I, weigh 1.6 grams of sodium nitrate and 1.9 grams of zirconium nitrate, dissolve them in 30 grams of water, then weigh 100 grams of alumina I, place them in the solution to allow full contact, then dry at 120°C for 4 hours, and calcine at 600°C for 2 hours to obtain alumina II.

[0095] IV: Weigh 1.8 g of sodium sulfide, dissolve it in 20 g of deionized water, then add it to alumina II and bake it at 150° C. for 12 hours to obtain the first sulfur-treated sample.

[0096] V: Weigh 79 grams of chromium nitrate, dissolve it in 30 grams of deionized water, add it to the first sulfur-treated sample, dry it at 120°C for 4 hours, and calcine it at 600°C for 2 hours to obtain a sample loaded with active components.

[0097] VI: Weigh 1.6 g of dimethyl sulfide, dissolve it in 10 g of anhydrous ethanol, and then add it to the sample loaded with active components. Then bake it at 150°C for 12 hours and calcine it at 550°C for 3 hours to obtain the final sample. The XPS spectrum is similar to Figure 1 Similarly, the dehydrogenation performance of the samples is shown in Table 1.

[0098] Example 4

[0099] The method of Example 1 is followed, except that in step IV, 1.5 g of sodium sulfide is weighed and dissolved in 30 g of deionized water for the first sulfidation; in step VI, 1.8 g of dimethyl sulfide is weighed and dissolved in 10 g of anhydrous ethanol for the second sulfidation, and the other conditions are the same. The XPS spectrum is Figure 1 Similarly, sample results are shown in Table 1.

[0100] Example 5

[0101] The method of Example 1 was followed, except that in step IV, 3.2 g of ammonium sulfide was weighed and dissolved in 30 g of deionized water for the first sulfidation; in step VI, 1.5 g of dimethyl sulfide was weighed and dissolved in 10 g of anhydrous ethanol for the second sulfidation, and the other conditions were the same. The XPS spectrum was Figure 1 Similarly, sample results are shown in Table 1.

[0102] Example 6

[0103] The method of Example 1 is followed, except that in step IV, 2 g of potassium sulfide is weighed and dissolved in 30 g of deionized water for the first sulfidation; in step VI, 2 g of diethyl sulfide is weighed and dissolved in 10 g of anhydrous ethanol for the second sulfidation, and the other conditions are the same. The XPS spectrum is Figure 1 Similarly, sample results are shown in Table 1.

[0104] Example 7

[0105] The method of Example 6 was followed, except that in step VI, 1.6 g of methyl ethyl sulfide was weighed, and the XPS spectrum was the same as Figure 1 Similarly, sample results are shown in Table 1.

[0106] Example 8

[0107] The method of Example 6 was followed, except that in step VI, 0.84 g of methyl ethyl sulfide and 1 g of diethyl sulfide were weighed. The XPS spectrum was the same as Figure 1 Similarly, sample results are shown in Table 1.

[0108] Example 9

[0109] The method of Example 6 was followed, except that in step IV, 2 g of diethyl sulfide was weighed and dissolved in 30 g of deionized water for the first sulfidation; in step VI, 2 g of potassium sulfide was weighed and dissolved in 10 g of anhydrous ethanol for the second sulfidation, and the other conditions were the same. The XPS spectrum was Figure 1 Similarly, sample results are shown in Table 1.

[0110] Comparative Example 1

[0111] I: Weigh 4000g aluminum nitrate nonahydrate and dissolve it in 1800g deionized water to form a solution. Dissolve 64g polyethylene glycol (average molecular weight 400) in the above solution. Pump in 40wt% ammonia solution. Measure the pH value of the system with a pH meter. The end point pH is about 5-6. Continue to stir the solution for 1h, let it stand for 12h, then filter it, wash it with deionized water 3 times, and put it in a 120℃ oven to dry for 12h to obtain the desired alumina precursor.

[0112] II: Weigh 400g of the above aluminum oxide precursor and 12g of sesbania powder, mix them at room temperature for 10 minutes, then add 120g of an aqueous solution of 40wt% nitric acid, continue kneading for 15 minutes to form a dough, and extrude it into a dough. The molded sample is left for 8 hours, dried in an oven at 120°C for 4 hours, and calcined at 600°C for 6 hours to obtain calcined aluminum oxide I.

[0113] III: First measure the water absorption rate of alumina I, weigh 1.6 grams of sodium nitrate and 1.9 grams of zirconium nitrate, dissolve them in 30 grams of water, then weigh 100 grams of alumina I, place them in the solution for equal volume immersion to ensure full contact, then dry at 120°C for 4 hours, and calcine at 600°C for 2 hours to obtain alumina II.

[0114] IV: Weigh 79 g of chromium nitrate, dissolve it in 30 g of deionized water, add it to alumina II, dry it at 120°C for 4 hours, and calcine it at 600°C for 2 hours to obtain the final sample.

[0115] That is, except that the above steps are not subjected to vulcanization, the other components, contents and preparation process are the same as those of Example 1. The results are shown in Table 1.

[0116] Figure 2 is the XPS spectrum of the catalyst sample surface S prepared in this comparative example 1, Figure 2 It can be seen that there is no S2p characteristic peak near the electron binding energy of 164 eV.

[0117] Comparative Example 2

[0118] The method and materials of Example 1 are the same, except that the first vulcanization of the carrier is not performed, and all the organic sulfides are introduced in the second vulcanization; the specific steps are as follows:

[0119] Weigh 4000g of aluminum nitrate nonahydrate and dissolve it in 1800g of deionized water to form a solution. Dissolve 64g of polyethylene glycol in the above solution. Pump in 40wt% ammonia solution. Measure the pH value of the system with a pH meter. The end point pH is about 5-6. Continue to stir the solution for 1h, let it stand for 12h, then filter it, wash it with deionized water 3 times, and put it in a 120℃ oven to dry for 12h to obtain the desired alumina precursor.

[0120] 400 g of the above-mentioned alumina precursor and 12 g of sesbania powder were weighed, mixed at room temperature for 10 minutes, and then 120 g of an aqueous solution of 40 wt% nitric acid was added, and kneaded for 15 minutes to form a dough, which was then extruded. The molded sample was left for 8 hours, dried in an oven at 120° C. for 4 hours, and calcined at 600° C. for 6 hours to obtain calcined alumina I.

[0121] First, measure the water absorption rate of aluminum oxide I. Weigh 1.6 grams of sodium nitrate and 1.9 grams of zirconium nitrate, dissolve them in 30 grams of water, then weigh 100 grams of aluminum oxide I, place it in the solution to allow it to fully contact, then dry it at 120°C for 4 hours, and calcine it at 600°C for 2 hours to obtain aluminum oxide II.

[0122] Weigh 79 grams of chromium nitrate, dissolve it in 30 grams of deionized water, add it to alumina II, dry it at 120° C. for 4 hours, and calcine it at 600° C. for 2 hours to obtain a sample loaded with active components.

[0123] 3.9 g of dimethyl sulfide was weighed, dissolved in 20 g of anhydrous ethanol, and then added to the sample loaded with the active component. The final sample was then baked at 150° C. for 12 hours and calcined at 550° C. for 3 hours. The results are shown in Table 1.

[0124] Figure 3 is the XPS spectrum of the catalyst sample surface S prepared in this comparative example 2, Figure 3 It can be seen that a weak S2p characteristic peak appears near the electron binding energy of 164 eV.

[0125] Comparative Example 3

[0126] The method and materials of Example 1 are the same, except that the second sulfidation of the catalyst is not performed, and the sulfide is introduced entirely in the first sulfidation. The specific steps are as follows:

[0127] Weigh 4000g of aluminum nitrate nonahydrate and dissolve it in 1800g of deionized water to form a solution. Dissolve 64g of polyethylene glycol in the above solution. Pump in 40wt% ammonia solution. Measure the pH value of the system with a pH meter. The end point pH is about 5-6. Continue to stir the solution for 1h, let it stand for 12h, then filter it, wash it with deionized water 3 times, and put it in a 120℃ oven to dry for 12h to obtain the desired alumina precursor.

[0128] 400 g of the above-mentioned alumina precursor and 12 g of sesbania powder were weighed, mixed at room temperature for 10 minutes, and then 120 g of an aqueous solution of 40 wt% nitric acid was added, and kneaded for 15 minutes to form a dough, which was then extruded. The molded sample was left for 8 hours, dried in an oven at 120° C. for 4 hours, and calcined at 600° C. for 6 hours to obtain calcined alumina I.

[0129] First, measure the water absorption rate of aluminum oxide I. Weigh 1.6 grams of sodium nitrate and 1.9 grams of zirconium nitrate, dissolve them in 30 grams of water, then weigh 100 grams of aluminum oxide I, place it in the solution to allow it to fully contact, then dry it at 120°C for 4 hours, and calcine it at 600°C for 2 hours to obtain aluminum oxide II.

[0130] Weigh 2.5 g of sodium sulfide, dissolve it in 30 g of deionized water, then add it to alumina II and bake it at 150° C. for 12 hours to obtain a sulfur-treated sample.

[0131] 79 g of chromium nitrate was weighed, dissolved in 30 g of deionized water, added to the sulfur-treated sample, dried at 120° C. for 4 hours, and calcined at 600° C. for 2 hours to obtain a sample loaded with active components. The results are shown in Table 1.

[0132] Figure 4 is the XPS spectrum of the catalyst sample surface S prepared in this comparative example 3, Figure 4 It can be seen that there is no S2p characteristic peak near the electron binding energy of 164 eV.

[0133] Table 1

[0134] Surface S content measured by XPS, % Propane conversion rate % Propylene selectivity % Example 1 0.34 42.4 89.9 Example 2 0.36 42.7 90.2 Example 3 0.37 42.5 90.8 Example 4 0.27 43.0 89.9 Example 5 0.39 42.1 92.1 Example 6 0.33 42.8 91.5 Example 7 0.35 42.5 91.7 Example 8 0.40 43.1 93.3 Example 9 0.25 41.5 89.6 Comparative Example 1 0 44.9 85.1 Comparative Example 2 0.12 44.7 85.5 Comparative Example 3 0.05 44.8 85.4

[0135] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for preparing a sulfided dehydrogenation catalyst, characterized in that: The preparation method comprises: (1) contacting the carrier with a first sulfide to perform a first sulfidation to obtain a sulfided carrier; (2) contacting the sulfided carrier with a dehydrogenation active component source solution to obtain a supported dehydrogenation catalyst; (3) contacting the supported dehydrogenation catalyst with a second sulfide to perform a second sulfidation to obtain a sulfided dehydrogenation catalyst.

2. The preparation method according to claim 1, wherein The amount of the first sulfide added is 30-90% of the total sulfur amount calculated as sulfur element, preferably 35-80%; and / or The first sulfide and the second sulfide are respectively selected from inorganic sulfides and / or organic sulfides; Preferably, the inorganic sulfide is selected from one or more of Na2S, K2S, (NH4)2S; Preferably, the organic sulfide is selected from alkyl sulfides, more preferably alkyl sulfides, more preferably one or more of methyl ethyl sulfide, dimethyl sulfide, and diethyl sulfide; Preferably, the first sulfide is selected from inorganic sulfides; The second sulfide is preferably selected from organic sulfides, particularly preferably alkyl sulfides, more preferably one or more of methyl ethyl sulfide, dimethyl sulfide, and diethyl sulfide, preferably a mixture of methyl ethyl sulfide and diethyl sulfide, more preferably a molar ratio of the two calculated on the basis of sulfur element is 0.1-10:

1.

3. The preparation method according to claim 1 or 2, wherein In step (1), the conditions for the first vulcanization include: The amount of the first sulfide added is 0.1-5%, preferably 0.5-3%, calculated as sulfur element and calculated as a percentage of the carrier mass; and / or The first sulfide and water form an aqueous solution which contacts the carrier to perform the first sulfidation, wherein the concentration of the aqueous solution is 3-15wt%; The contact method is immersion contact; and / or After contacting, drying is performed to complete the first vulcanization, the drying temperature is 140-160° C., and the drying time is 10-20 hours.

4. The preparation method according to any one of claims 1 to 3, wherein In step (3), the conditions for the second vulcanization include: the amount of the second sulfide added is 10-70% of the total sulfur amount calculated as sulfur element, preferably 20-65%; The second sulfide and the solvent form a solution which contacts with the supported dehydrogenation catalyst to perform the second sulfidation, wherein the concentration of the solution is 10-20 wt %, and the solvent is anhydrous ethanol; The contact method is immersion contact; and / or After contact, drying and calcination are performed to complete the second vulcanization; Preferably, the drying temperature is 140-160°C and the drying time is 10-20h; The calcination temperature is 500-600°C and the calcination time is 2-4h.

5. The preparation method according to any one of claims 1 to 4, wherein: The carrier contains Group IA and / or Group IVB elements; and a carrier base; Preferably, The content of Group IA elements, calculated as elements, accounts for 0.3 to 3% of the weight of the carrier; and / or The content of group IVB elements, calculated as elements, accounts for 0.3 to 2% of the weight of the carrier; More preferably, The Group IA element is selected from one or more of Na, K, Rb, and Cs, preferably at least one of Na and K; and / or The Group IVB element is Ti and / or Zr, preferably Zr; More preferably, The Group IA and / or Group IVB elements are introduced onto the carrier base by an impregnation method to form the carrier.

6. The preparation method according to any one of claims 1 to 5, wherein: The dehydrogenation active component element is selected from the metal elements of Group VIB, preferably one or more of Cr, Mo, W, more preferably Cr; and / or The content of the dehydrogenation active component elements is 10-25% based on the total weight of the catalyst.

7. The preparation method according to claim 5, wherein: The carrier base is selected from alumina and / or silica; and / or The carrier base is powder or shaped particles; Preferably, the carrier base is obtained by precipitation of a carrier precursor, optionally followed by shaping; More preferably, the carrier precursor is one or more of pseudo-boehmite, boehmite, alumina sol, alumina gel, and silica sol.

8. The sulfided dehydrogenation catalyst prepared by the preparation method according to any one of claims 1 to 7, preferably, based on the total weight of the catalyst, the sulfided dehydrogenation catalyst comprises: Calculated by elements, 0.5-5% sulfur, 10-25% dehydrogenation active component, 0.3-3% Group IA element additive and / or 0.3-2% Group IVB element additive.

9. Use of the sulfided dehydrogenation catalyst according to claim 8 in dehydrogenating alkanes to produce olefins, preferably, the alkanes are one or more of C2-C6 alkanes.

10. A propane dehydrogenation method, characterized in that: The method comprises: subjecting propane to a dehydrogenation reaction in the presence of a catalyst, wherein the catalyst comprises the sulfided dehydrogenation catalyst according to claim 8; Preferably, the conditions for the dehydrogenation reaction include: a reaction temperature of 600-650°C, a reaction pressure of 0.05-0.2 MPa, and a propane mass space velocity of 0.4-1.0 h -1 .

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