Dehydrogenation catalyst, preparation method and application thereof, and method for preparing butadiene through oxidative dehydrogenation of butylene

Abstract

The invention relates to a dehydrogenation catalyst as well as a preparation method and application thereof and a method for preparing butadiene by oxidative dehydrogenation of butylene, and provides a dehydrogenation catalyst which comprises a spinel phase, an alpha-iron oxide phase and an antioxidant alloy component, the antioxidant alloy components are selected from at least three of an IVB group, a VIB group and a VIII group; a hydrogenation active center is introduced by adopting a method of adding an antioxidant metal alloy component into a spinel structure, and a small amount of hydrogen generated in the reaction is utilized to perform hydrogenation reaction to inhibit the generation of aldehydes, so that the content of the aldehydes in organic byproducts in dehydrogenation products is greatly reduced, and the selectivity of the catalyst is improved.

Description

Technical Field

[0001] The invention relates to a dehydrogenation catalyst, a preparation method and application thereof, and a method for preparing butadiene by oxidative dehydrogenation of butene. Background Art

[0002] Butadiene is a very important basic chemical raw material and an important monomer for producing polymer synthetic materials. It can be copolymerized with a variety of compounds to produce synthetic resins such as styrene-butadiene rubber, nitrile-butadiene rubber, and acrylonitrile-butadiene-styrene terpolymer resin. It can also be used to produce other products such as adiponitrile (nylon 66 monomer), cyclopentane, anthraquinone, and tetrahydrofuran.

[0003] At present, there are two main production methods for butadiene: refinery steam cracking to produce ethylene and co-production of C4 extraction and separation, and butene oxidation. About 97% of the world's butadiene production capacity uses the cracking C4 extraction process, which has economic advantages. However, due to the rapid development of shale gas mining technology in recent years, the output of butadiene produced by cracking C4 extraction will decrease. From 2000 to 2010, the proportion of ethylene production units using naphtha as raw material in all ethylene units decreased from 55% to 47%. As the global demand for butadiene production shows a growing trend, it is difficult for cracking units to produce butadiene to meet the demand. Butene oxidation dehydrogenation to produce butadiene technology has once again become a research hotspot. This technology can not only get rid of dependence on petroleum resources, but also fill the gap in the butadiene market.

[0004] There are three main types of catalysts used for the oxidative dehydrogenation of butene: Mo-Bi system, Sn-P-Li system, and Fe-salt system. Iron-based catalysts have the advantages of mild reaction conditions, high catalytic activity, and more specific selectivity, and are currently the most widely used. USP3270080 discloses AB2O4 (A is generally Mg 2+ 、Zn 2+ 、Co 2+ and Ni 2+ Equivalent metal ions, B is Fe 3+ ions) iron-based spinel catalysts for the oxidative dehydrogenation of butene to butadiene, but the performance is not very stable. USP3450788 and USP3595810 disclose the introduction of Cr 3+ It can improve the stability of the catalyst. The synthetic rubber plant of Yanshan Petrochemical Company has put into production the B02 catalyst for the chromium-free iron-based butene oxidative dehydrogenation to butadiene used in adiabatic fixed bed.

[0005] Although the above technologies have achieved huge economic benefits in industrial applications, and the activity of the catalyst and the selectivity of the target product have also reached a high level, the high level of aldehyde products in the butene oxidative dehydrogenation products during the production process makes the subsequent heat exchange unit easy to clog, causing a great impact on production operations.

[0006] Therefore, there is still a need in the art to develop a catalyst for the oxidative dehydrogenation of butene to prepare butadiene, further reducing the content of organic by-products in the dehydrogenation product and improving the selectivity of the catalyst. Summary of the invention

[0007] The purpose of the present invention is to overcome the problem of high aldehyde content in oxidative dehydrogenation products in the prior art, and to provide a dehydrogenation catalyst and a preparation method. The catalyst introduces a hydrogenation active center by adding an antioxidant metal alloy component in a spinel phase, and utilizes a small amount of hydrogen generated in the reaction to undergo a hydrogenation reaction to inhibit the generation of aldehydes. When the catalyst is applied to the oxidative dehydrogenation of butene to produce butadiene, it has the advantages of low aldehyde content in organic by-products in the dehydrogenation products and high catalyst selectivity.

[0008] In order to achieve the above objectives, the present invention provides a dehydrogenation catalyst, which includes: a spinel phase, an α-iron oxide phase, and an antioxidant alloy component; the antioxidant alloy component is selected from at least three of Group IVB, Group VIB and Group VIII.

[0009] The second aspect of the present invention provides a method for preparing the catalyst described in the present invention, which comprises: (1) co-precipitating an iron source, an inorganic salt required to form a spinel phase and an alkali source, aging, washing, and obtaining a first slurry; (2) optionally contacting an antioxidant alloy component with an alkali source and washing it to neutrality; (3) contacting the antioxidant alloy component with the first slurry in step (1) and a high molecular weight organic matter to obtain a second slurry, ball milling, drying, forming, and calcining; (4) contacting the sample calcined in step (3) in a mixed atmosphere of H2 and water vapor.

[0010] The third aspect of the present invention provides use of the catalyst of the present invention in oxidative dehydrogenation of light olefins.

[0011] A fourth aspect of the present invention provides a method for preparing butadiene by oxidative dehydrogenation of butene, the method comprising: contacting butene, a diluent, an oxidant and a catalyst for reaction; the catalyst comprises the catalyst described in the present invention.

[0012] Through the above technical solution, the present invention has the following beneficial effects:

[0013] The present invention introduces a hydrogenation active center by adding an oxidation-resistant metal alloy component into the spinel phase, utilizes a small amount of hydrogen generated in the reaction to undergo a hydrogenation reaction to inhibit the generation of aldehydes, greatly reduces the content of aldehydes in the organic by-products in the dehydrogenation product, and improves the selectivity of the catalyst. DETAILED DESCRIPTION

[0014] 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.

[0015] In one aspect, the present invention provides a dehydrogenation catalyst, which comprises: a spinel phase, an α-iron oxide phase, and an anti-oxidation alloy component; the anti-oxidation alloy component is selected from at least three of group IVB, group VIB and group VIII.

[0016] In the present invention, there is no special requirement for each component in the anti-oxidation alloy component. As long as they contain at least three of the aforementioned IVB group, VIB group and VIII group, the purpose of the present invention can be achieved. The content of each component in the alloy is not less than 5% by weight, preferably not less than 10% by weight.

[0017] According to a preferred embodiment of the present invention, based on 100 wt % of the catalyst, the content of the spinel phase is 60-90 wt %, preferably 70-80 wt %.

[0018] According to a preferred embodiment of the present invention, based on 100 wt % of the catalyst, the content of the α-iron oxide phase is 10-40 wt %, preferably 20-30 wt %.

[0019] According to a preferred embodiment of the present invention, based on 100 wt % of the catalyst, the content of the anti-oxidation alloy component is 0.1-5 wt %, preferably 1-3 wt %.

[0020] By adopting the above-mentioned preferred embodiment, the content of aldehydes in the organic by-products in the dehydrogenation product can be reduced and the selectivity of the catalyst can be improved.

[0021] In the present invention, the particle size of the antioxidant alloy component can be selected in a wide range. According to a preferred embodiment of the present invention, the particle size of the antioxidant alloy component is 1-150 microns, preferably 2-100 microns. The aforementioned preferred embodiment can increase the hydrogenation active center of the catalyst, thereby reducing the generation of aldehydes in the product.

[0022] In the present invention, the antioxidant alloy component has a wide range of optional components. According to a preferred embodiment of the present invention, the antioxidant alloy component is selected from at least three of Cr, Ni, Ti, Rh, Pt, and Re. Preferably, the antioxidant alloy component is Ni-Cr-Ti alloy and / or Ni-Pt-Cr alloy. The aforementioned preferred embodiment can improve the effect of inhibiting the generation of aldehydes by reacting with hydrogen and improve the catalyst selectivity.

[0023] In the present invention, the acid center density on the catalyst surface can be selected in a wide range. According to a preferred embodiment of the present invention, the acid center density on the catalyst surface is 90-300 μmmol / g, preferably 150-200 μmol / g. By adopting the above preferred embodiment, the hydrogenation active center of the catalyst can be increased, thereby reducing the generation of aldehydes in the product.

[0024] In the present invention, the pore volume of the catalyst can be selected in a wide range. According to a preferred embodiment of the present invention, the pore volume of the catalyst is 0.1-1 ml / g, preferably 0.2-0.3 ml / g. The above preferred embodiment can reduce the content of aldehydes in the organic by-products in the dehydrogenation product and improve the selectivity of the catalyst.

[0025] In the present invention, the average pore size of the catalyst can be selected in a wide range. According to a preferred embodiment of the present invention, the average pore size of the catalyst is 10-60 nm, preferably 20-22 nm. By adopting the above preferred embodiment, the content of aldehydes in the organic by-products in the dehydrogenation product can be reduced, and the selectivity of the catalyst can be improved.

[0026] In the present invention, the specific surface area of ​​the catalyst can be selected in a wide range. According to a preferred embodiment of the present invention, the specific surface area of ​​the catalyst is 20-80 m 2 / g, preferably 35-45m 2 By adopting the above preferred embodiment, the hydrogenation active center of the catalyst can be increased, thereby reducing the generation of aldehydes in the product.

[0027] According to a preferred embodiment of the present invention, the spinel structure satisfies the chemical formula: A x Fe2O4, A is selected from at least one of Ca, Mn, Co, Ni, Cu, Zn, Cd, Hg, Mg, Sn, Al, Co, Bi, Ti, and V, preferably at least three of Ca, Mn, Co, Ni, Cu, Zn, Cd, Hg, Mg, Sn, Al, Co, Bi, Ti, and V; and x satisfies the requirements of valence. The above preferred embodiment can reduce the content of aldehydes in the organic by-products in the dehydrogenation product and improve the selectivity of the catalyst.

[0028] Dehydrogenation catalysts having the aforementioned characteristics can be used in the present invention, and there are no special requirements for their preparation methods. According to the present invention, a preparation method for a dehydrogenation catalyst is provided, which comprises: (1) co-precipitating an iron source, an inorganic salt required to form a spinel phase and an alkali source, aging, washing, and obtaining a first slurry; (2) optionally contacting an antioxidant alloy component with an alkali source and washing to neutrality; (3) contacting the antioxidant alloy component with the first slurry in step (1) and a high molecular weight organic matter to obtain a second slurry, ball milling, drying, forming, and calcining; (4) contacting the sample calcined in step (3) in a mixed atmosphere of H2 and water vapor.

[0029] In the present invention, in order to obtain a uniformly mixed material, operations such as ball milling are performed as needed. This operation is well known to those skilled in the art and can be performed with reference to the prior art.

[0030] In the present invention, part of the added iron source is used to form the spinel phase and part is used to form the α-iron oxide phase. The structure of the anti-oxidation alloy component in the present invention does not change before and after preparation and remains an alloy structure.

[0031] In the present invention, there is no special requirement for the solvent, which is well known to those skilled in the art. Deionized water is used as an example, but the scope of the present invention is not limited thereto. The amount of deionized water can be adjusted according to actual needs, but the scope of the present invention is not limited thereto.

[0032] In the present invention, the conditions and time of heating, slow dripping and stirring are flexibly selected according to the type and amount of the substance, which is a well-known operation method for those skilled in the art and will not be described in detail herein.

[0033] In the present invention, in the step (1), there is no special requirement for the washing step, which is an exemplary description, but does not limit the scope of the present invention. Deionized water is used as the solvent for washing, and there is no special requirement for the amount of deionized water used, which only needs to meet the experimental requirements. This operation is well known to those skilled in the art and will not be described in detail in the present invention.

[0034] In the present invention, the high molecular weight organic matter can be selected from a wide range. According to a preferred embodiment of the present invention, the high molecular weight organic matter is at least one of polyethylene glycol, starch, cellulose and sucrose, etc. In the embodiment, cellulose is used as an example, but the scope of the present invention is not limited thereto. By adopting the above preferred embodiment, the hydrogenation active center of the catalyst can be increased, thereby reducing the generation of aldehydes in the product.

[0035] In the present invention, there is no special requirement for the alkali source. According to a preferred embodiment of the present invention, the alkali source is selected from at least one of sodium hydroxide, potassium hydroxide, sodium carbonate and ammonia water. In the embodiment, ammonia water is used for exemplary description, but the scope of the present invention is not limited thereto. By adopting the above preferred embodiment, the hydrogenation active center of the catalyst can be increased, thereby reducing the generation of aldehydes in the product.

[0036] In the present invention, based on 100wt% of the mixture of high molecular weight organic matter, inorganic salts required to form the spinel phase, iron source and antioxidant alloy components, the mass of the high molecular weight organic matter can be selected in a wide range. According to a preferred embodiment of the present invention, based on 100wt% of the mixture of high molecular weight organic matter, inorganic salts required to form the spinel phase, iron source and antioxidant alloy components, the mass of the high molecular weight organic matter is 0.1-3wt%, preferably 1.5-3wt%. The above preferred embodiment can increase the hydrogenation active center of the catalyst, thereby reducing the generation of aldehydes in the product.

[0037] In the present invention, based on 100wt% of the mixture of high molecular weight organic matter, inorganic salt required for forming spinel structure, iron source and anti-oxidation alloy component, the mass of the inorganic salt required for forming spinel structure can be selected in a wide range. According to a preferred embodiment of the present invention, based on 100wt% of the mixture of high molecular weight organic matter, inorganic salt required for forming spinel structure, iron source and anti-oxidation alloy component, the mass of the inorganic salt required for forming spinel structure is 5-30wt%, preferably 15-20wt%. The above preferred embodiment can increase the hydrogenation active center of the catalyst, thereby reducing the generation of aldehydes in the product.

[0038] In the present invention, based on 100wt% of the mixture of high molecular weight organic matter, inorganic salts required to form the spinel structure, iron source and antioxidant alloy components, the mass of the iron source can be selected in a wide range. According to a preferred embodiment of the present invention, based on 100wt% of the mixture of high molecular weight organic matter, inorganic salts required to form the spinel structure, iron source and antioxidant alloy components, the mass of the iron source is 40-90wt%, preferably 70-80wt%. The aforementioned preferred embodiment can increase the hydrogenation active center of the catalyst, thereby reducing the generation of aldehydes in the product.

[0039] In the present invention, based on 100wt% of the mixture of high molecular weight organic matter, inorganic salts required to form the spinel structure, iron source and antioxidant alloy component, the mass of the antioxidant alloy component can be selected in a wide range. According to a preferred embodiment of the present invention, based on 100wt% of the mixture of high molecular weight organic matter, inorganic salts required to form the spinel structure, iron source and antioxidant alloy component, the mass of the alloy is 0.1-5wt%, preferably 0.3-0.6wt%. The aforementioned preferred embodiment can increase the hydrogenation active center of the catalyst, thereby reducing the generation of aldehydes in the product.

[0040] According to a preferred embodiment of the present invention, the coprecipitation temperature is 10-50°C, preferably 20-40°C.

[0041] According to a preferred embodiment of the present invention, the pH value of the co-precipitation is 8-11, preferably 8.5-9.8.

[0042] By adopting the above-mentioned preferred embodiment, the hydrogenation active center of the catalyst can be increased, thereby reducing the generation of aldehydes in the product.

[0043] In the present invention, in the step (1), there is no special requirement for the aging conditions. According to a preferred embodiment of the present invention, the aging time is 0.5-4h. In the embodiment, 2h is used as an exemplary illustration, but the scope of the present invention is not limited thereto. By adopting the above preferred embodiment, the content of aldehydes in the organic by-products in the dehydrogenation product can be reduced, and the selectivity of the catalyst can be improved.

[0044] In the present invention, in the step (2), there is no special requirement for the conditions of contacting the alkali source with the antioxidant alloy component for purification as needed. The purpose is to purify the alloy, which is well known to those skilled in the art. In the embodiment, leaching industrial-grade alloy powder with a 2.5 mol / L NaOH solution is used as an example, but the scope of the present invention is not limited thereto.

[0045] In the present invention, in the step (2), there is no special requirement for the washing operation, which is well known to those skilled in the art. In the embodiment, the washing is performed several times with anhydrous ethanol until it becomes neutral, and the washing is performed in anhydrous ethanol for storage for exemplary purposes, but the scope of the present invention is not limited thereto.

[0046] In the present invention, in the step (3), after obtaining the second slurry and before drying and forming, the mixed slurry can be stirred, and the step of ball milling (colloid) at room temperature, for example, for 2 hours, is aimed at uniform mixing. This operation can be performed with reference to the prior art.

[0047] In the present invention, in the step (3), the second slurry solid content can be selected in a wide range. According to a preferred embodiment of the present invention, the second slurry solid content is 5-40wt%, and 30wt% is used as an example in the embodiment, but the scope of the present invention is not limited thereto. The aforementioned preferred embodiment can increase the hydrogenation active center of the catalyst, thereby reducing the generation of aldehydes in the product.

[0048] In the present invention, the solid content of the second slurry is controlled by adding deionized water.

[0049] In the present invention, in the step (3), there is no special requirement for the molding method. According to a preferred embodiment of the present invention, the molding is carried out by spray drying molding or pressing molding. Spray drying molding is used as an example in the embodiments, but the scope of the present invention is not limited thereto.

[0050] In the present invention, after spray drying and before calcination, the material formed into microspheres in the spray dryer can be dried at 90° C. for 12 hours.

[0051] According to a preferred embodiment of the present invention, the calcination is performed in an air atmosphere.

[0052] According to a preferred embodiment of the present invention, the calcination temperature is 550-900°C, preferably 620-750°C.

[0053] According to a preferred embodiment of the present invention, the calcination time is 4-18 hours, and 6 hours is used as an example in the examples, but the scope of the present invention is not limited thereto.

[0054] By adopting the above-mentioned preferred embodiment, the hydrogenation active center of the catalyst can be increased, thereby reducing the generation of aldehydes in the product.

[0055] In the present invention, in step (4), the volume ratio of H2 to water vapor in the mixed atmosphere can be selected in a wide range. According to a preferred embodiment of the present invention, in the mixed atmosphere, H2: water vapor = 1:2-1:20, preferably 1:5-1:10. In the embodiment, H2: water = 1:8 is used for exemplary description, but the scope of the present invention is not limited thereto. The aforementioned preferred embodiment can increase the hydrogenation active center of the catalyst, thereby reducing the generation of aldehydes in the product.

[0056] In the present invention, in step (4), there is no special requirement for the contact conditions, which is only for illustrative purposes, but does not limit the scope of the present invention.

[0057] According to a preferred embodiment of the present invention, the contact temperature is 300-500° C., preferably 350-420° C. The contact temperature in the examples is 400° C. for exemplary purposes, but the scope of the present invention is not limited thereby.

[0058] According to a preferred embodiment of the present invention, the contact time is 2-6 hours. In the examples, the contact time is 4 hours for exemplary description, but the scope of the present invention is not limited thereto.

[0059] By adopting the above-mentioned preferred embodiment, the hydrogenation active center of the catalyst can be increased, thereby reducing the generation of aldehydes in the product.

[0060] The present invention provides the use of the catalyst of the present invention in the dehydrogenation process of preparing light olefins, preferably in the oxidative dehydrogenation process of light monoolefins.

[0061] The present invention provides a method for preparing butadiene by oxidative dehydrogenation of butene, which comprises: contacting butene, a diluent, an oxidant and a catalyst for reaction; the catalyst comprises the catalyst of the present invention.

[0062] In the present invention, there is no special requirement for the molar ratio of the oxidant to butene. According to a preferred embodiment of the present invention, the molar ratio of the oxidant to butene is 0.4-1. The molar ratio of the oxidant to butene in the embodiment is 0.7 for illustrative purposes, but the scope of the present invention is not limited thereto.

[0063] In the present invention, there is no special requirement for the molar ratio of the diluent to butene. According to a preferred embodiment of the present invention, the molar ratio of the diluent to butene is 2-16. In the embodiment, the molar ratio of the diluent to butene is 12 for exemplary description, but the scope of the present invention is not limited thereto. There is no special requirement for the type of diluent, such as water vapor.

[0064] In the present invention, there is no special requirement for the conditions of the contact reaction.

[0065] According to a preferred embodiment of the present invention, the temperature of the contact reaction is 320-560° C., and 420° C. is used as an example in the examples, but the scope of the present invention is not limited thereto.

[0066] According to a preferred embodiment of the present invention, the pressure of the contact reaction is 0.01-0.8 MPa. In the examples, 0.03 MPa is used for exemplary purposes, but the scope of the present invention is not limited thereto.

[0067] According to a preferred embodiment of the present invention, the butene volume space velocity of the contact reaction is 300-800h -1 In the embodiment, 400h -1 This is intended to be exemplary only and does not limit the scope of the invention.

[0068]

[0069]

[0070] (Ai ——peak area of ​​component i in the sample; R i ——Relative mass correction factor of component i to butadiene).

[0071] In the present invention, the composition of the catalyst: spinel phase, α-iron oxide phase, and anti-oxidation alloy component are obtained through X-ray diffraction testing, and the composition of each component is obtained through elemental analysis testing.

[0072] The particle size of the anti-oxidation alloy component is measured by a particle size tester.

[0073] The acid center density on the catalyst surface is obtained by NH3-TPD (temperature programmed desorption of ammonia) testing.

[0074] The pore volume, average pore diameter and specific surface area of ​​the catalyst are measured by BET specific surface area detection method.

[0075] Example 1

[0076] (1) 3.75 g of zinc nitrate, 6.87 g of cobalt nitrate, 29.54 g of magnesium nitrate and 179.18 g of ferric nitrate were dissolved in 3 L of distilled water, and a 15 wt% aqueous ammonia solution was added dropwise under rapid stirring until the precipitation end point pH was 9.0. The mixture was stirred at 30° C. for 30 minutes, and allowed to stand at room temperature for 2 hours. The resulting slurry was filtered and washed;

[0077] (2) 1.00 g of industrial grade Ni-Cr-Ti (Ni:Cr:Ti=6:2.5:1.5 (mass ratio)) alloy powder (particle size 50 μm) was leached with 2.5 mol / L NaOH solution, and then washed several times with anhydrous ethanol until neutral. The prepared sample was stored in anhydrous ethanol and added to the slurry of the previous step. 5 g of cellulose was added to the above active component slurry to control the solid content to 30 wt %. The mixture was stirred for 10 minutes and ball milled (colloid) at room temperature for 2 hours to obtain a slurry. Microspheres were formed in a spray dryer and finally dried at 90°C for 12 hours. The mixture was moved into a muffle furnace at 700°C and calcined for 6 hours. The obtained sample was treated at 400°C for 4 hours in an atmosphere with a H2:H2O volume ratio of 1:8 to obtain a catalyst sample. The parameters are shown in Table 2.

[0078] (3) Using butene, air and water vapor as raw materials, the reaction temperature is 420°C, the pressure is 0.03 MPa, and the volume space velocity is 400 h -1 The experimental results under the conditions of 0.7 molar ratio of oxygen to olefin and 12 molar ratio of water to olefin are shown in Table 1.

[0079] Example 2

[0080] (1) 2.39 g of nickel nitrate, 12.98 g of cobalt nitrate, 23.84 g of magnesium nitrate and 164.86 g of ferric nitrate were dissolved in 3 L of distilled water, and a 15 wt % ammonia solution was added dropwise under rapid stirring until the pH value of the precipitation end point was 8.5. The mixture was stirred at 40° C. for 30 minutes, and allowed to stand at room temperature for 2 hours. The resulting slurry was filtered and washed;

[0081] (2) 1.00 g of industrial grade Ni-Cr-Ti (Ni:Cr:Ti=6:2.5:1.5) alloy powder (particle size: 100 μm) was leached with 2.5 mol / L NaOH solution, and then washed several times with anhydrous ethanol until neutral. The prepared sample was stored in anhydrous ethanol and added to the slurry of the previous step. 5 g of cellulose was added to the above active component slurry to control the solid content to 30 wt %. The mixture was stirred for about 10 minutes and ball (colloid) milled for 2 hours at room temperature to obtain a slurry. Microspheres were formed in a spray dryer and finally dried at 90°C for 12 hours and then transferred to a muffle furnace at 750°C for calcination for 6 hours. The obtained sample was then treated at 400°C for 4 hours in an atmosphere with a H2:H2O volume ratio of 1:8 to obtain a catalyst sample. The parameters are shown in Table 2.

[0082] (3) Using butene, air and water vapor as raw materials, the reaction temperature is 420°C, the pressure is 0.03 MPa, and the volume space velocity is 400 h -1 The experimental results under the conditions of 0.7 molar ratio of oxygen to olefin and 12 molar ratio of water to olefin are shown in Table 1.

[0083] Example 3

[0084] (1) 1.65 g of zinc nitrate, 4.68 g of copper nitrate, 3.64 g of nickel nitrate, 21.98 g of magnesium nitrate and 141.66 g of ferric nitrate were dissolved in 3 L of distilled water, and a 15 wt% aqueous ammonia solution was added dropwise under rapid stirring until the precipitation end point pH was 9.0. The mixture was stirred at 20° C. for 30 minutes, allowed to stand at room temperature for 2 hours, and the resulting slurry was filtered and washed;

[0085] (2) 1.00 g of industrial grade Ni-Pt-Cr (Ni:Pt:Cr=6.5:1.5:2.5) alloy powder (particle size: 80 μm) was leached with 2.5 mol / L NaOH solution, and then washed several times with anhydrous ethanol until neutral. The prepared sample was stored in anhydrous ethanol and added to the slurry of the previous step. 5 g of cellulose was added to the above active component slurry to control the solid content to 30 wt %. The mixture was stirred for about 10 minutes and ball (colloid) milled for 2 hours at room temperature to obtain a slurry. Microspheres were formed in a spray dryer and finally dried at 90°C for 12 hours and then transferred to a muffle furnace at 620°C for calcination for 6 hours. The obtained sample was then treated at 400°C for 4 hours in an atmosphere with a H2:H2O volume ratio of 1:8 to obtain a catalyst sample. The parameters are shown in Table 2.

[0086] (3) Using butene, air and water vapor as raw materials, the reaction temperature is 420°C, the pressure is 0.03 MPa, and the volume space velocity is 400 h -1 The experimental results under the conditions of 0.7 molar ratio of oxygen to olefin and 12 molar ratio of water to olefin are shown in Table 1.

[0087] Example 4

[0088] All conditions are the same as those in Example 1, except that the materials in step (1) are: 1.39 g zinc nitrate, 4.68 g cobalt nitrate, 24.96 g magnesium nitrate and 158.64 g ferric nitrate. The parameters are shown in Table 2.

[0089] The experimental results are shown in Table 1.

[0090] Example 5

[0091] All conditions are the same as those in Example 1, except that in step (2): 1.00 g of industrial grade Ni-Cr-Ti alloy powder (particle size 150 μm), parameters are shown in Table 2;

[0092] The experimental results are shown in Table 1.

[0093] Example 6

[0094] All conditions were the same as in Example 1, except that in step (2), the sintering was performed in a muffle furnace at 900° C. for 12 hours. The parameters are shown in Table 2.

[0095] The experimental results are shown in Table 1.

[0096] Example 7

[0097] All conditions are the same as those in Example 1, except that the materials in step (1) are: 13.84 g of magnesium nitrate, 23.49 g of tin chloride and 164.86 g of ferric nitrate dissolved in 3 L of distilled water. The parameters are shown in Table 2.

[0098] The experimental results are shown in Table 1.

[0099] Example 8

[0100] All conditions were the same as in Example 1, except that the precipitation endpoint pH in step (1) was 10.5; parameters are shown in Table 2

[0101] The experimental results are shown in Table 1.

[0102] Example 9

[0103] All conditions were the same as in Example 1, except that the catalyst was not treated with a mixed atmosphere of H2:H2O. The parameters are shown in Table 2.

[0104] The experimental results are shown in Table 1.

[0105] Comparative Example 1

[0106] (1) 3.75 g of zinc nitrate, 6.87 g of cobalt nitrate, 29.54 g of magnesium nitrate and 179.18 g of ferric nitrate were dissolved in 3 L of distilled water, and a 15 wt% aqueous ammonia solution was added dropwise under rapid stirring until the precipitation end point pH was 9.0. The mixture was stirred at 50° C. for 30 minutes, allowed to stand at room temperature for 2 hours, and the resulting slurry was filtered and washed;

[0107] (2) The above active component slurry was prepared with a solid content of 30 wt%, stirred for about 10 minutes, and ball-milled at room temperature for 2 hours to obtain a slurry, which was then formed into microspheres in a spray dryer. Finally, the slurry was dried at 90°C for 12 hours and then calcined in a muffle furnace for 6 hours at a furnace temperature of 750°C to obtain a catalyst sample. The parameters are shown in Table 2.

[0108] (3) Using butene, air and water vapor as raw materials, the reaction temperature is 420°C, the pressure is 0.03 MPa, and the volume space velocity is 400 h -1 The experimental results under the conditions of 0.7 molar ratio of oxygen to olefin and 12 molar ratio of water to olefin are shown in Table 1.

[0109] Comparative Example 2

[0110] All conditions were the same as those in Example 1, except that 1.25 g of industrial grade Sn-Sb alloy powder (particle size 50 μm) was leached in step (2). The experimental results are shown in Table 1.

[0111] Table 1

[0112] Butene conversion % Butadiene selectivity % Acetaldehyde byproduct content in water phase % hydrogen / % Example 1 82.45 93.54 0.135 0.86 Example 2 81.97 93.49 0.143 0.92 Example 3 82.04 93.28 0.146 0.89 Example 4 81.13 93.20 0.162 1.05 Example 5 81.43 93.21 0.158 1.02 Example 6 81.95 93.19 0.165 1.12 Example 8 81.76 93.24 0.172 1.23 Example 9 81.26 93.15 0.263 1.56 Comparative Example 1 82.36 93.05 0.316 1.94 Comparative Example 2 80.51 92.58 0.308 1.83

[0113] It can be seen from the results in Table 1 that the invention has a significantly better effect of inhibiting the generation of aldehydes by adding an anti-oxidative metal alloy component to the spinel structure.

[0114] Table 2

[0115]

[0116] 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 dehydrogenation catalyst, characterized in that The catalyst comprises: a spinel phase, an alpha-iron oxide phase, and an anti-oxidation alloy component; The oxidation resistant alloy components are selected from at least three of Group IVB, Group VIB and Group VIII.

2. The catalyst according to claim 1, wherein Based on 100 wt% of catalyst, The content of spinel phase is 60-90wt%, preferably 70-80wt%; and / or The content of α-iron oxide phase is 10-40wt%, preferably 20-30wt%; and / or The content of the anti-oxidation alloy component is 0.1-5wt%, preferably 1-3wt%; and / or The particle size of the anti-oxidation alloy component is 1-150 microns, preferably 2-100 microns; and / or The anti-oxidation alloy components are selected from at least three of Cr, Ni, Ti, Rh, Pt and Re, preferably the anti-oxidation alloy components are Ni-Cr-Ti alloy and / or Ni-Pt-Cr alloy; and / or The acid center density on the catalyst surface is 90-300 μmmol / g, preferably 150-200 μmol / g; and / or The pore volume of the catalyst is 0.1-1 ml / g, preferably 0.2-0.3 ml / g; and / or The average pore size of the catalyst is 10-60 nm, preferably 20-22 nm; and / or The specific surface area of ​​the catalyst is 20-80m 2 / g, preferably 35-45m 2 / g.

3. The catalyst according to claim 1 or 2, The spinel phase satisfies the chemical formula: A x Fe2O4, among which A is at least one selected from the group consisting of Ca, Mn, Co, Ni, Cu, Zn, Cd, Hg, Mg, Sn, Al, Co, Bi, Ti, and V, preferably at least three selected from the group consisting of Ca, Mn, Co, Ni, Cu, Zn, Cd, Hg, Mg, Sn, Al, Co, Bi, Ti, and V; The value of x satisfies the valence requirement.

4. A method for preparing the catalyst according to any one of claims 1 to 3, characterized in that: The method includes: (1) co-precipitating an iron source, an inorganic salt required to form a spinel phase, and an alkali source, aging, and washing to obtain a first slurry; (2) optionally contacting the anti-oxidation alloy component with an alkali source and washing it to neutrality; (3) contacting the antioxidant alloy component with the first slurry in step (1) and the high molecular weight organic matter to obtain a second slurry, ball milling, drying, forming, and calcining; (4) The sample calcined in step (3) is exposed to a mixed atmosphere of H2 and water vapor.

5. The method according to claim 4, wherein: The high molecular weight organic substance is at least one of polyethylene glycol, starch, cellulose and sucrose; and / or The alkali source is selected from at least one of sodium hydroxide, potassium hydroxide, sodium carbonate and ammonia water.

6. The method according to claim 4 or 5, wherein: Based on 100 wt% of the mixture of high molecular weight organic matter, inorganic salts required to form the spinel phase, iron source and antioxidant alloy components, The mass of the high molecular weight organic matter is 0.1-3wt%, preferably 1.5-3wt%; and / or The mass of the inorganic salt required to form the spinel phase is 5-30wt%, preferably 15-20wt%; and / or The mass of the iron source is 40-90wt%, preferably 70-80wt%; and / or The weight of the anti-oxidation alloy component is 0.1-5wt%, preferably 0.3-0.6wt%; and / or The coprecipitation conditions include: Temperature 10-50°C; preferably 20-40°C; and / or pH 8-11, preferably 8.5-9.8; and / or The aging conditions include: time 0.5-4h.

7. The method according to any one of claims 1 to 6, wherein: In step (3), The second slurry has a solid content of 5-40wt%; and / or Forming is by spraying or pressing; and / or The calcination is carried out in an air atmosphere, and the calcination conditions include: The temperature is 550-900°C, preferably 620-750°C; and / or the time is 4-18 hours; and / or In step (4), in the mixed atmosphere, the volume ratio of H2: water vapor is 1:2-1:20, preferably 1:5-1:10; and / or the contact conditions include: temperature 300-500°C, preferably 350-420°C; and / or time is 2-6 hours.

8. Use of the catalyst according to any one of claims 1 to 3 in the oxidative dehydrogenation of light hydrocarbons, preferably in the oxidative dehydrogenation of light monoolefins.

9. A method for preparing butadiene by oxidative dehydrogenation of butene, characterized in that: The method includes: Butene, a diluent, an oxidant and a catalyst are contacted and reacted; the catalyst comprises the catalyst described in any one of claims 1-3.

10. The method according to claim 9, wherein: The contact reaction conditions include: a temperature of 320-560°C; and / or a volume space velocity of butene of 300-800 h -1 ; and / or pressure 0.01-0.8MPa; and / or The molar ratio of diluent to butene is 2-16; and / or The molar ratio of the oxidant to butene is 0.4-1.

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