Non-noble metal ethane dehydrogenation catalyst and ethane dehydrogenation method

Abstract

The present invention discloses a non-noble metal ethane dehydrogenation catalyst and an ethane dehydrogenation method, the catalyst contains a carrier and a non-noble metal dehydrogenation active component loaded on the carrier, the carrier contains a first metal element and a second metal element, the first metal element comprises Al, the second metal element is selected from the IVB group, and the first metal element is selected from the IVB group, the second metal element is selected from the IVB group, and the second metal element is selected from the IVB group. The particle size distribution of the carrier is in a range of 15-50 microns based on Dx (90). The catalyst does not contain precious metal or elements harmful to the environment, and is easy to prepare, high in activity and good in target object selectivity.

Description

Technical Field

[0001] The present invention relates to a non-noble metal ethane dehydrogenation catalyst and an ethane dehydrogenation method. Background Art

[0002] As the most important olefin product, ethylene is the main raw material for downstream products such as synthetic fibers, synthetic rubber, and synthetic plastics. However, due to the lack of oil resources in my country, the rise in crude oil prices, and the environmental problems caused by the production of ethylene through traditional oil routes, the production of ethylene through non-traditional oil routes has great market prospects, among which the ethane dehydrogenation production of ethylene route is an important source of ethylene.

[0003] The main methods for ethane dehydrogenation to ethylene include steam thermal cracking and catalytic dehydrogenation. Ethane steam cracking is relatively mature, but the furnace temperature of steam cracking requires a high temperature of 1000-1200℃, which is a very energy-intensive process. Ethane catalytic dehydrogenation can reduce the reaction temperature and achieve high-efficiency and low-energy production of ethylene. To this end, it is necessary to prepare a dehydrogenation catalyst with good performance and optimize the dehydrogenation process route. At present, there are many research reports, including the design of catalysts and the selection of process route conditions. The selection of CO in the process route 2 As an oxidant for the oxidative dehydrogenation of ethane, for example, CN201610134338.5 discloses a modified chromium oxide catalyst with a special pore structure for the catalytic oxidation of ethane by carbon dioxide to produce ethylene. Although a higher ethylene yield is obtained, the catalyst has limited improvement in ethylene selectivity during the reaction.

[0004] At present, the catalysts for ethane dehydrogenation to ethylene are still mainly based on Pt and CrOx. Due to the high cost of Pt metal and the high cost of CrOx, 6+ It is carcinogenic and harmful to the environment, which greatly limits the development of these two dehydrogenation catalysts. It is particularly important to develop ethane dehydrogenation catalysts that are active, cheap, safe and environmentally friendly.

[0005] CN105727978B discloses a method for preparing a catalyst for ethane oxidative dehydrogenation to ethylene. In order to improve the conversion rate of ethane and the selectivity of ethylene, the main active component of the catalyst used is Ni, and the carrier is alumina. However, the catalyst preparation requires reduction treatment of the catalyst precursor, and when the catalyst is used to catalyze ethane dehydrogenation, the dehydrogenation reaction raw gas composition needs to include ethane / oxygen in a molar ratio of 1:1 to 1:3, and the raw gas can contain Ar, N 2 Or diluent gases such as He, when the reaction temperature is 400-600°C, the ethane conversion rate is relatively high due to the addition of more diluent gases, but the ethylene selectivity is low, less than 57.3%.

[0006] CN106984297A discloses a method for producing ethylene by dehydrogenation of ethane in a carbon dioxide atmosphere, wherein the catalyst is SiO 2 Doped TiO 2 As carrier, SiO 2 The doping amount is 1.0% to 20.0% by mass percentage, and gallium oxide is used as the active component. It is prepared by impregnation method, wherein the active component content is 1.0% to 15.0%. The reaction is carried out in a fixed bed reactor under normal pressure, the reaction temperature is 550 to 750°C, the total flow rate of the raw gas is 10 to 50 mL / min, wherein the molar percentage of each component in the raw gas is 1 to 5% ethane, 3 to 30% carbon dioxide, and the rest is nitrogen. According to the reaction results, the ethylene yield is 30% and the selectivity is higher than 80%, but due to the low content of ethane in the entire raw material, the dehydrogenation economy is poor.

[0007] CN111013563A discloses a spinel catalyst for ethane dehydrogenation to ethylene in a carbon dioxide atmosphere and its preparation method. The catalyst is a magnesium aluminum spinel doped with gallium oxide, and its general formula is: MgGa x Al 2-x O 4 (x = 0.5-2), the doping amount of gallium oxide in the preferred embodiment is above 50%. Although the catalytic dehydrogenation of ethane to ethylene in a carbon dioxide atmosphere has a high ethane conversion rate and ethylene selectivity, the content of ethane in the mixed feed is relatively low, accounting for only 1-5%. Although the ethylene yield is 43.9% and the selectivity is 87%, there are still major problems in terms of economic efficiency.

[0008] CN115634678A provides an ethane dehydrogenation catalyst, which uses non-precious metal as an active component, including a first metal component, a second metal component and a third metal component; wherein the first metal component is a combination of two or more of Fe, Zn and Ga elements, the second metal component is one or more of alkali metals, alkaline earth metals, rare earth metals, Cu and Mn elements; the third metal component is one or more of compounds containing V, Mo, W, Ni and Zr elements; the mass content of the above catalysts is not less than 50%, 0-30% and 0-20% respectively in terms of metal oxide. Although the dehydrogenation reaction has a high ethane conversion rate (more than 33%) and good ethylene selectivity (more than 83%), the reaction process requires water vapor and / or nitrogen as a diluent gas, the operation cost is high and the difficulty is great.

[0009] In summary, the existing ethane dehydrogenation catalysts all have certain defects, and it is very important to develop a new non-precious metal dehydrogenation catalyst. Summary of the invention

[0010] The purpose of the present invention is to overcome the problem of using precious metals or environmentally harmful catalysts in the prior art, and to provide a non-precious metal or environmentally friendly ethane dehydrogenation catalyst, which has the advantages of easy preparation, good activity and good target selectivity.

[0011] 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.

[0012] The present invention provides a non-precious metal ethane dehydrogenation catalyst, which comprises a carrier and a non-precious metal dehydrogenation active component loaded on the carrier, wherein the carrier comprises a first metal element and a second metal element, wherein the first metal element comprises Al, and the second metal element is selected from the IVB group, and the particle size distribution of the carrier is in the range of 15-50 microns in terms of Dx (90). The average particle size distribution of the carrier of the present invention is relatively narrow. The catalyst of the present invention does not contain precious metals or elements harmful to the environment, and is easy to prepare, has high activity, and has good stability.

[0013] According to a preferred embodiment of the present invention, preferably, the non-precious metal dehydrogenation active component is selected from one or more of Group VIII, Group IB, and Group IIB, preferably selected from one or more of Zn, Fe, Co, Ni, and Cu, and more preferably one or more of Zn, Fe, and Ni. In the embodiments of the present invention, Zn is used as an example to illustrate the advantages of the present invention, but the scope of the present invention is not limited thereby.

[0014] According to a preferred embodiment of the present invention, preferably, the content of the non-precious metal dehydrogenation active component as an element is 1 to 20%, preferably 2 to 15%, based on the total weight of the catalyst.

[0015] According to a preferred embodiment of the present invention, the catalyst preferably contains a Group IIIA promoter element, preferably, based on the total weight of the catalyst, the content of the Group IIIA element as an element is 0.1-5%, preferably 0.2-3%.

[0016] According to a preferred embodiment of the present invention, preferably, preferably, the Group IIIA element is at least one of B, Ga, and In, preferably Ga.

[0017] According to a preferred embodiment of the present invention, the particle size distribution of the bimetallic oxide carrier is in the range of 18-35 microns in terms of Dx(90); the carrier having this characteristic can thus enable the raw material to enter the carrier and the product to be quickly desorbed, so that the catalyst has good activity.

[0018] According to a preferred embodiment of the present invention, the crystal characteristics of the bimetallic oxide carrier include: containing 1-10 weight % of γ-phase alumina, preferably containing 2-6 weight % of γ-phase alumina; the carrier having such characteristics can be used in a catalyst to improve the performance of the catalyst.

[0019] According to a preferred embodiment of the present invention, the physicochemical characteristics of the bimetallic oxide carrier further include: an average pore size distribution of 3-15 nm.

[0020] In the present invention, the molar ratio of the second metal element to the first metal element can be selected in a wide range. According to a preferred embodiment of the present invention, the molar ratio of the second metal element to the first metal element is 0.01 to 0.1.

[0021] In the present invention, the first metal element includes Al, but is not limited to Al, and other elements may be introduced as needed. In the embodiment of the present invention, the first metal element is Al as an example to illustrate the advantages of the present invention.

[0022] In the present invention, the second metal element is selected from one or more of Ti, Zr, and Hf, preferably Zr. Other elements may also be introduced as needed.

[0023] In the present invention, preferably, the carrier contains element B, and more preferably, the molar ratio of element B to the second metal element is 0.01-0.03: 1. This can further improve the performance of the carrier when applied to the catalyst.

[0024] The carriers with the characteristics of the present invention can achieve the purpose of the present invention, and there is no special requirement for their preparation methods. According to one embodiment of the present invention, the preparation method of the carrier includes: mixing a first metal source, a second metal source, an optional boron source, and a hydroxyl-containing polymer, and then crystallizing, cooling, solid-liquid separation, drying, and roasting under alkaline conditions. The target carrier of the present invention can be prepared by the above method, and the above method has simple steps and a wide range of material sources.

[0025] In the present invention, the dosage ratio of each material can be selected in a wide range. The following exemplary description is given, but the scope of the present invention is not limited thereto. According to a preferred embodiment of the present invention, the molar ratio of the first metal source: the second metal source: deionized water: the hydroxyl-containing polymer: the alkali is = (10-100): 1: (20-500): (0.1-10): (30-80), preferably (20-100): 1: (100-300): (0.2-5): (30-50).

[0026] In the present invention, all hydroxyl-containing polymers are applicable to the present invention. According to the present invention, the average molecular weight of the hydroxyl-containing polymer is preferably 200-2500, preferably 400-1025. The above preferred technical solution can well achieve the purpose of the present invention.

[0027] In the present invention, various types of hydroxyl-containing polymers can be applied to the present invention. According to the present invention, the hydroxyl-containing polymer is preferably selected from polyethylene glycol and / or polyallyl alcohol.

[0028] In the present invention, polyethylene glycol is, for example: having a molecular weight of 200 to 600, being liquid at room temperature; and being a transparent, colorless or substantially colorless viscous liquid.

[0029] In the present invention, polyallyl alcohol is, for example, generally divided into three types according to average molecular weights of 425, 1025 and 2025, non-volatile, soluble in water (low molecular weight) and organic solvents such as aliphatic ketones and alcohols, and insoluble in ether and most aliphatic hydrocarbons.

[0030] According to a preferred embodiment of the present invention, preferably, the average molecular weight of the polyethylene glycol is 200-600.

[0031] According to a preferred embodiment of the present invention, preferably, the polyallyl alcohol is selected from one or more of those with an average molecular weight of 425, 1025 and 2025.

[0032] According to a preferred embodiment of the present invention, preferably, the hydroxyl-containing polymer is selected from a mixed polymer of polyethylene glycol with an average molecular weight of 400 and polyallyl alcohol with an average molecular weight of 1025, and the ratio of the two is 0.1-10:1. In the embodiment, 1:1 is used as an example to illustrate the advantages of the present invention, but the scope of the present invention is not limited thereby. This can further improve the performance of the carrier applied to the catalyst.

[0033] In the present invention, the crystallization conditions can be selected in a wide range. The following is an exemplary description, but the scope of the present invention is not limited thereto. Crystallization refers to a hydrothermal reaction in a reactor. According to a preferred embodiment of the present invention, the crystallization conditions include: a temperature of 150-200°C, preferably 150-180°C.

[0034] In the present invention, the crystallization time can be selected in a wide range and is determined specifically according to needs. According to a preferred embodiment of the present invention, the crystallization conditions include: the time is 12-48h, preferably 12-24h.

[0035] In the present invention, there is no special requirement for the conditions of drying and roasting, and the following is an exemplary description, but the scope of the present invention is not limited thereby.

[0036] According to one embodiment of the present invention, the drying conditions include: a temperature of 80-120° C. and a time of 12-24 hours.

[0037] According to a preferred embodiment of the present invention, the calcination conditions include: a temperature of 500-750° C. and a time of 2-12 h; preferably, a temperature of 600-650° C. and a time of 4-6 h.

[0038] In the present invention, there is no special requirement for the type of the first metal source, and various substances are suitable for the present invention. The following exemplary description does not limit the scope of the present invention. According to one embodiment of the present invention, the first metal source includes one or more of aluminum nitrate nonahydrate, aluminum sulfate, aluminum isopropoxide and aluminum sol.

[0039] In the present invention, there is no special requirement for the type of the second metal source, and various substances are applicable to the present invention. The following exemplary description does not limit the scope of the present invention. According to one embodiment of the present invention, the second metal source is selected from a second metal soluble compound, preferably a second metal soluble salt, preferably zirconium nitrate and / or zirconium oxychloride.

[0040] In the present invention, the boron source can be selected from a wide range, and commonly used substances can be used in the present invention. For the present invention, the boron source is preferably selected from one or more of boric acid and organic boron compounds. Boric acid is used as an example to illustrate the advantages of the present invention, but the present invention is not limited to this.

[0041] In the present invention, the base used has a wide range of materials to be selected, and commonly used bases can be applied to the present invention, mainly used to provide an alkaline environment. The following exemplary description is given for the present invention, but the scope of the present invention is not limited thereto. Preferably, the base is selected from organic amines and / or inorganic ammonia.

[0042] In the present invention, the optional range of types of the organic amine substances is relatively wide, and commonly used organic amine substances can be applicable to the present invention, for example, one or more of ethylamine, propylamine, dimethylamine, ethylenediamine, diethylamine, diisopropylamine, hexamethylenediamine, monoethanolamine, diethanolamine, triethanolamine, 3-propanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, 1,2-dimethylpropylamine, sec-butylamine, ethylenediamine, 1,2-propylenediamine, 1,4-butylenediamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide or tetrapropylammonium hydroxide.

[0043] In the present invention, there is no special requirement for the step of mixing the first metal source, the second metal source, and the optional boron source hydroxyl-containing polymer. The main purpose is to mix them evenly. For example, the materials can be mixed evenly by appropriate heating and dripping. The following exemplary description, but not limiting the scope of the present invention, includes the following steps:

[0044] (1) adding the first metal source and the second metal source into deionized water in proportion at 20-50° C., stirring and dissolving the mixture to obtain a mixed solution I;

[0045] (2) Add the hydroxyl-containing polymer to the mixed solution I and stir evenly.

[0046] In the present invention, in order to achieve crystallization under alkaline conditions, the alkaline substance may be introduced during mixing, or after mixing. The present invention has no special requirements for this. According to one embodiment of the present invention, the alkaline substance is introduced after mixing, for example, the step of introducing the alkaline substance after mixing includes:

[0047] (1) adding the first metal source and the second metal source into deionized water in proportion at 20-50° C., stirring and dissolving the mixture to obtain a mixed solution I;

[0048] (2) adding a hydroxyl-containing polymer to the mixed solution I and stirring uniformly;

[0049] (3) Add the alkaline solution dropwise to the solution obtained in step (2), and continue stirring for 1-3 hours after the addition.

[0050] According to a preferred embodiment of the present invention, the method for preparing the carrier comprises:

[0051] (1) adding the first metal source and the second metal source into deionized water in proportion at 20-50° C., stirring and dissolving the mixture to obtain a mixed solution I;

[0052] (2) adding a hydroxyl-containing polymer to the mixed solution I and stirring evenly;

[0053] (3) adding an alkaline solution dropwise to the solution obtained in step (2), and continuing stirring for 1-3 hours after the addition;

[0054] (4) The mixed solution obtained in step (3) is then poured into a crystallization kettle, crystallized at 150-200° C. for 12-48 hours, then cooled to room temperature, filtered, and the obtained solid product is dried at 80-120° C. for 12-24 hours, and then calcined at 500-750° C. for 2-12 hours to obtain a carrier.

[0055] The present invention has no special requirements for the preparation method of the catalyst. According to the present invention, a preparation method of the non-precious metal dehydrogenation catalyst is provided, and the preparation method comprises:

[0056] (1) preparing a carrier according to the method of the present invention;

[0057] (2) The non-noble metal dehydrogenation active component source and optionally the IIIA group auxiliary agent source are loaded onto the carrier by an impregnation method, followed by drying and calcining.

[0058] In the present invention, there is no special requirement for the impregnation method, which is exemplary but not intended to limit the scope of the present invention. The impregnation method is an equal volume impregnation method.

[0059] In the present invention, there is no special requirement for the conditions of drying and roasting, and the following is an exemplary description, but the scope of the present invention is not limited thereby.

[0060] According to one embodiment of the present invention, the drying conditions include: a temperature of 80-120° C. and a time of 12-24 hours.

[0061] According to a preferred embodiment of the present invention, the calcination conditions include: a temperature of 500-750° C. and a time of 2-12 h.

[0062] The present invention provides an ethane dehydrogenation method, which comprises: subjecting ethane to a dehydrogenation reaction, wherein the catalyst comprises the dehydrogenation catalyst of the present invention.

[0063] In the present invention, there is no special requirement for the dehydrogenation reaction conditions, which are described below for exemplary purposes, but the scope of the present invention is not limited thereby.

[0064] According to one embodiment of the present invention, preferably, the conditions for the dehydrogenation reaction include: a reaction temperature of 500-850°C, a reaction pressure of 0.01-0.2 MPa, and a volume space velocity of 0.4-0.8 h -1 .

[0065] The carrier of the present invention is a composite carrier formed by two metals, and its average particle size distribution is relatively narrow, so that the raw material can enter the carrier, the product can be quickly desorbed, and the catalyst has good activity.

[0066] The carrier preparation method of the present invention is relatively simple and easy to implement.

[0067] The catalyst of the present invention does not contain precious metals or elements harmful to the environment, is easy to prepare, has high activity and good target selectivity. DETAILED DESCRIPTION

[0068] The present invention will be described in detail below through examples. In the following examples, the particle size distribution of the bimetallic oxide carrier is obtained by dry method testing using a Malvern particle size analyzer, the crystal form of the bimetallic oxide carrier is obtained by XRD analysis combined with instrument configuration identification software, and the average pore size distribution of the oxide is obtained by the BET method; all raw materials used are analytically pure products commercially available from China Pharmaceutical Group.

[0069] In the present invention, particle size distribution (particle size) is what is shown by particles or particle aggregates, and pore size distribution is the size inside particles.

[0070] Particle size testing methods include:

[0071] The particle size of the carrier was analyzed by Malvern 3000 particle size analyzer. The test method was as follows: first clean the particle size analyzer and set the test parameters, where the Venturi tube was set to the standard value, the test pressure was 2 bar, the test powder was added, the file name was set, and the test was started. The instrument automatically completed the background scan and three powder parallel tests. After the test, the test data was processed through the editing option to obtain the Dx (90) particle size of the double oxide carrier.

[0072] The test method for the γ-alumina crystal phase content is: using the German BRUKER X-ray powder diffractometer (XRD), model D8 Advance SS (18kW), rotating target (copper target) X-ray generator: maximum power 18KW, voltage and current 60KV*300mA, conventional test. Crystal phase analysis uses system software to automatically perform peak identification and analysis.

[0073] The test method for the average pore size of the double oxide carrier is to use the physical adsorption instrument ASAP2020M+C of Micromeritics Instruments, USA, to perform fully automatic specific surface area and mesopore / micropore analysis.

[0074] In the following examples, molecular weight refers to average molecular weight.

[0075] The dehydrogenation method is as follows: ethane gas and nitrogen are adjusted by mass flow meter at a volume ratio of 1:1, enter the preheating zone for preheating, and then enter the reaction zone. The heating section and reaction section of the reactor are heated by electric heating wire to reach a predetermined temperature. The inner diameter of the reactor is a quartz tube with a length of 400mm and an inner diameter of 8mm. The reacted gas passes through a condenser and enters a gas chromatograph to analyze its composition.

[0076] The catalyst evaluation conditions in the isothermal fixed bed reactor are as follows: 1 g of catalyst and 1 g of quartz sand with a size of 20-40 mesh after sieving are weighed and mixed evenly, and then loaded into the above isothermal fixed bed reactor. The reaction pressure is normal pressure, pure ethane is fed, and the gas mass space velocity is 0.4 h -1, reaction temperature 720° C. After 12 minutes of reaction, the gas after reaction was analyzed by gas chromatography to analyze the content of each component, and the conversion rate of ethane and the selectivity of ethylene were calculated.

[0077] In the present invention, the conversion rate is calculated as follows: ethane conversion rate (%) = (ethane amount - ethane content in the reaction product) / ethane amount × 100%;

[0078] The selectivity is calculated as follows: ethylene selectivity (%) = actual ethylene production / theoretical ethylene production × 100%.

[0079] Example 1

[0080] Preparation of vector:

[0081] Aluminum isopropoxide, zirconium nitrate, deionized water, polyethylene glycol (molecular weight 400), and diethanolamine were weighed according to a molar ratio of 20:1:100:5:30;

[0082] At 25°C, dissolve aluminum isopropoxide and zirconium nitrate in deionized water and stir thoroughly to dissolve. Then slowly drop polyethylene glycol liquid and stir for 1 hour to mix evenly. Then drop diethanolamine into the solution and continue stirring for 2 hours. The obtained mixed solution is introduced into a crystallization kettle and crystallized at 150°C for 12 hours. The obtained solution is centrifuged, and the filter cake is transferred to an oven and dried at 80°C for 12 hours, and then placed in a muffle furnace and calcined at 600°C for 4 hours to obtain ZrO 2 -Al 2 O 3 The double oxide carrier has a Dx(90) particle size of 35 microns, a γ-alumina content of 2.41%, and an average pore size of the double oxide of 4.9 nm.

[0083] Preparation of catalyst:

[0084] Weigh 2.33 g of zinc nitrate and 0.16 g of gallium nitrate, dissolve in 8 g of deionized water to obtain a solution containing active components, add solution I to 20 g of the above-mentioned carrier to allow sufficient contact, then dry in an oven at 80°C for 12 h, transfer to a muffle furnace and calcine at 600°C for 4 h to obtain a catalyst sample.

[0085] The ethane conversion was 29% and the ethylene selectivity was 88%.

[0086] Example 2

[0087] The method of Example 1 is followed, except that the steps for preparing the carrier are as follows:

[0088] Alumina sol, zirconium oxychloride, deionized water, polyethylene glycol (molecular weight 200) and propylamine were weighed according to the molar ratio of 50:1:200:0.2:50. The crystallization temperature was 180°C for 18 hours; the double oxide carrier was calcined at 650°C for 4 hours in a muffle furnace to obtain a Dx(90) particle size of 29 microns, of which γ-Al 2 O 3 It accounts for 2.51%, and the average pore size of double oxide is 5.3nm.

[0089] The ethane conversion was 27% and the ethylene selectivity was 89%.

[0090] Example 3

[0091] The method of Example 1 is followed, except that: the preparation steps of the carrier are as follows: aluminum nitrate nonahydrate, zirconium nitrate, deionized water, polyethylene glycol (molecular weight 600) and ethylenediamine are weighed in sequence according to the molar ratio of aluminum nitrate nonahydrate, zirconium nitrate, deionized water, polyethylene glycol (molecular weight 600) and ethylenediamine of 100:1:300:0.5:30. The crystallization temperature is 180°C and the time is 24h; the dual oxide carrier is calcined in a muffle furnace at 650°C for 6h to obtain a Dx(90) particle size of 27 microns, wherein γ-Al 2 O 3 The proportion is 2.91%, the average pore size of the double oxide is 6.5nm. The ethane conversion rate is 28%, and the ethylene selectivity is 87%.

[0092] Example 4

[0093] According to the method of Example 1, except that the molecular weight of polyethylene glycol is 900, a double oxide carrier is obtained, and its Dx(90) particle size is 18 microns, wherein γ-Al 2 O 3 The proportion is 2.31%, the average pore size of the double oxide is 3.8nm. The ethane conversion rate is 26%, and the ethylene selectivity is 85%.

[0094] Example 5

[0095] According to the method of Example 1, except that the polymer is polyallyl alcohol with a molecular weight of 4100, a double oxide carrier is obtained, and its Dx(90) particle size is 23 microns, wherein γ-Al 2 O 3 The proportion is 2.45%, the average pore size of the double oxide is 4.5nm. The ethane conversion rate is 25%, and the ethylene selectivity is 86%.

[0096] Example 6

[0097] According to the method of Example 1, the difference is that

[0098] Aluminum nitrate nonahydrate, zirconium nitrate, deionized water, polyethylene glycol and diethanolamine were weighed according to a molar ratio of 200:1:200:0.2:50, and the other conditions were the same to obtain a double oxide carrier with a Dx(90) particle size of 45 μm, of which γ-Al 2 O 3 The proportion is 15%, the average pore size of the double oxide is 18nm. The ethane conversion rate is 24%, and the ethylene selectivity is 88%.

[0099] Example 7

[0100] According to the same preparation method as in Example 3, but with a crystallization temperature of 240°C and a treatment time of 36 h, a double oxide support was obtained, whose Dx(90) particle size was 49 μm, wherein γ-Al 2 O 3 The proportion is 21%, the average pore size of the double oxide is 19nm. The ethane conversion rate is 24%, and the ethylene selectivity is 85%.

[0101] Example 8

[0102] The method of Example 1 is followed, except that an auxiliary agent B is introduced during the preparation of the carrier:

[0103] Boric acid, aluminum isopropoxide, zirconium nitrate, deionized water, polyethylene glycol and diethanolamine were weighed according to a molar ratio of boric acid to zirconium nitrate of 0.01:1, and a molar ratio of aluminum isopropoxide, zirconium nitrate, deionized water, polyethylene glycol (molecular weight 400) and diethanolamine of 20:1:100:5:30;

[0104] At 25°C, dissolve boric acid, aluminum isopropoxide and zirconium nitrate in deionized water and stir thoroughly to dissolve. Then slowly drop polyethylene glycol liquid and stir for 1 hour to mix evenly. Then drop diethanolamine into the solution and continue stirring for 2 hours. The obtained mixed solution is introduced into a crystallization kettle. The crystallization conditions remain unchanged to obtain a B-containing double oxide carrier, wherein the double oxide carrier has a Dx(90) particle size of 33 microns, wherein γ-Al 2 O 3 The proportion is 5.6%, and the average pore size of the double oxide is 7.1nm. In the catalyst preparation, Zn and Ga are introduced in the same way, and finally a non-precious metal dehydrogenation catalyst containing B and Ga is obtained. The ethane conversion rate is 30% and the ethylene selectivity is 91%.

[0105] Example 9

[0106] The method of Example 1 was followed, except that the carrier preparation process was: using the same molar amount of polyallyl alcohol with a molecular weight of 425. The Dx(90) particle size of the double oxide carrier was 25 microns, the γ-alumina content was 3.41%, and the average pore size of the double oxide was 4.4 nm. The ethane conversion was 28%, and the ethylene selectivity was 88%.

[0107] Example 10

[0108] The method of Example 1 was followed, except that in the carrier preparation process: polyethylene glycol with a molecular weight of 400 and polyallyl alcohol with a molecular weight of 1025 were added simultaneously at a molar ratio of 1:1, and the total molar amount of the two was the same as the amount of polymer used in Example 1. The Dx (90) particle size of the double oxide carrier was 31 microns, the γ-alumina content was 2.48%, and the average pore size of the double oxide was 4.6 nm. The ethane conversion rate was 32%, and the ethylene selectivity was 93%.

[0109] Comparative Example 1

[0110] The method of Example 1 was followed, except that polyethylene glycol was not added in the preparation of the carrier, and the particle size distribution of the obtained carrier Dx (90) was 103 μm. The other conditions were the same. The ethane conversion rate was 19%, and the ethylene selectivity was 81%.

[0111] 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 non-precious metal ethane dehydrogenation catalyst, characterized in that: The catalyst contains a carrier and a non-precious metal dehydrogenation active component supported on the carrier, wherein the carrier contains a first metal element and a second metal element, wherein the first metal element includes Al, and the second metal element is selected from Group IVB. The particle size distribution of the carrier is in the range of 15-50 microns in terms of Dx(90).

2. The catalyst according to claim 1, wherein The non-precious metal dehydrogenation active component is selected from one or more of Group VIII, Group IB, and Group IIB, preferably selected from one or more of Zn, Fe, Co, Ni, and Cu, and more preferably selected from one or more of Zn, Fe, and Ni; The non-precious metal dehydrogenation active component is present in an amount of 1 to 20%, preferably 2 to 15%, based on the total weight of the catalyst, calculated as an element; Preferably, the catalyst contains a group IIIA promoter element, preferably, the content of the group IIIA element as an element is 0.1 to 5%, preferably 0.2 to 3%, based on the total weight of the catalyst; Preferably, the Group IIIA element is at least one of Ga and In, preferably Ga.

3. The catalyst according to claim 1 or 2, wherein The particle size distribution of the bimetallic oxide carrier is in the range of 18-35 microns based on Dx(90); and / or The crystal characteristics of the bimetallic oxide carrier include: containing 1-10 wt% of γ-phase alumina, preferably containing 2-6 wt% of γ-phase alumina; and / or The physicochemical characteristics of the bimetallic oxide carrier include: an average pore size distribution of 3-15 nm.

4. The catalyst according to any one of claims 1 to 3, wherein The molar ratio of the second metal element to the first metal element is 0.01 to 0.1; and / or The first metal element is Al; and / or The second metal element is selected from one or more of Ti, Zr, and Hf, preferably Zr; Preferably, the carrier contains element B, and the molar ratio of element B to the second metal element is 0.01-0.03:

1.

5. The catalyst according to any one of claims 1 to 4, wherein The preparation method of the carrier comprises: mixing a first metal source, a second metal source, an optional boron source, and a hydroxyl-containing polymer, and then crystallizing, cooling, solid-liquid separation, drying, and calcining under alkaline conditions; Preferably, The molar ratio of the first metal source: the second metal source: deionized water: the hydroxyl-containing polymer: the base is (10-100): 1: (20-500): (0.1-10): (30-80), preferably (20-100): 1: (100-300): (0.2-5): (30-50).

6. The catalyst according to claim 5, wherein The average molecular weight of the hydroxyl-containing polymer is 200-2500, preferably 400-1025; and / or The hydroxyl-containing polymer is selected from polyethylene glycol and / or polyallyl alcohol; Preferably, the average molecular weight of polyethylene glycol is 200 to 600; The polyallyl alcohol is selected from one or more of those having an average molecular weight of 425, 1025 and 2025; Preferably, the hydroxyl-containing polymer is selected from a mixed polymer of polyethylene glycol with an average molecular weight of 400 and polyallyl alcohol with an average molecular weight of 1025, and the usage ratio of the two is 0.1-10:

1.

7. The catalyst according to claim 5 or 6, wherein The crystallization conditions include: a temperature of 150-200°C, preferably 150-180°C; and / or a time of 12-48h, preferably 12-24h; and / or Drying conditions include: temperature of 80-120°C, time of 12-24h; and / or The calcination conditions include: a temperature of 500-750° C. and a time of 2-12 hours; preferably, a temperature of 600-650° C. and a time of 4-6 hours.

8. The catalyst according to any one of claims 5 to 7, wherein The first metal source comprises one or more of aluminum nitrate nonahydrate, aluminum sulfate, aluminum isopropoxide and aluminum sol; and / or The second metal source is selected from a second metal soluble compound, preferably a second metal soluble salt, preferably zirconium nitrate and / or zirconium oxychloride; and / or The boron source is selected from one or more of boric acid and organic boron compounds; and / or The base is selected from organic amines and / or inorganic ammonia; Preferably, the organic amine is selected from one or more of ethylamine, propylamine, dimethylamine, ethylenediamine, diethylamine, diisopropylamine, hexyldiamine, monoethanolamine, diethanolamine, triethanolamine, 3-propanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, 1,2-dimethylpropylamine, sec-butylamine, ethylenediamine, 1,2-propylenediamine, 1,4-butylenediamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide and tetrapropylammonium hydroxide.

9. The catalyst according to any one of claims 5 to 8, wherein The preparation method of the carrier comprises: (1) adding the first metal source, the second metal source, and optionally the boron source into deionized water in proportion at 20-50° C., stirring and dissolving the mixture to obtain a mixed solution I; (2) adding a hydroxyl-containing polymer to the mixed solution I and stirring evenly; (3) adding an alkaline solution dropwise to the solution obtained in step (2), and continuing stirring for 1-3 hours after the addition; (4) The mixed solution obtained in step (3) is then poured into a crystallization kettle, crystallized at 150-200° C. for 12-48 hours, then cooled to room temperature, filtered, and the obtained solid product is dried at 80-120° C. for 12-24 hours, and then calcined at 500-750° C. for 2-12 hours to obtain a carrier.

10. An ethane dehydrogenation method, characterized in that: The method comprises: subjecting ethane to a dehydrogenation reaction, wherein the catalyst comprises the dehydrogenation catalyst according to any one of claims 1 to 9; Preferably, The conditions for the dehydrogenation reaction include: reaction temperature of 500-850°C, reaction pressure of 0.01-0.2MPa, mass space velocity of 0.4-0.8h -1 .