CN111054407A

CN111054407A - Catalyst for preparing butadiene by oxidative dehydrogenation of butylene

Info

Publication number: CN111054407A
Application number: CN201811201477.0A
Authority: CN
Inventors: 曾铁强; 缪长喜; 吴文海; 樊志贵; 姜冬宇
Original assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Current assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Priority date: 2018-10-16
Filing date: 2018-10-16
Publication date: 2020-04-24

Abstract

The invention relates to a catalyst for preparing butadiene through oxidative dehydrogenation of butylene and a preparation method thereof, and mainly solves the problem of low butadiene selectivity in the existing technology for preparing butadiene through oxidative dehydrogenation of butylene. The invention provides a catalyst for preparing butadiene through oxidative dehydrogenation of butylene, wherein the catalyst is CO at 400-500 DEG C₂The adsorption capacity is larger than that of CO at room temperature₂10% of saturated adsorption amount, and the catalyst comprises the following components: a) m in spinel structure^IIFe₂O₄A main active component, wherein M is at least one selected from the group consisting of Zn, Mg, Mn, Co and Ni; b) with the structural general formula A_aB_bC_cO_xAs an auxiliary agent, in molRatio meter, to M^IIFe₂O₄Has the chemical formula of M^IIFe₂O₄·A_aB_bC_cO_xThe technical scheme of the catalyst solves the problem well, and can be used in the industrial production of butadiene through oxidative dehydrogenation of butylene.

Description

Catalyst for preparing butadiene by oxidative dehydrogenation of butylene

Technical Field

The invention relates to a catalyst for preparing butadiene by oxidative dehydrogenation of butylene and a preparation method thereof.

Background

1, 3-butadiene is an important monomer for chemical products such as synthetic rubber and resin, and plays an important role in petrochemical olefin raw materials. The industrial production method of butadiene mainly comprises two methods of carbon four extraction separation and butylene dehydrogenation which are co-produced in the process of preparing ethylene by steam cracking. The method for obtaining butadiene by adopting the carbon four extraction method is economically advantageous, and the pyrolysis carbon four extraction process is adopted in the vast majority of butadiene production capacity in the world at present. However, butadiene is obtained as a by-product of the cracking unit, and it is difficult to increase its yield by adding the cracking unit. Moreover, as refinery feedstocks are upgraded, butadiene production will be reduced, creating a continuing bias in global butadiene supply.

With the rapid development of the synthetic rubber and resin industry and the wider and wider application of butadiene, the market demand of butadiene is continuously increased. Butadiene obtained by extracting naphtha cracking products cannot meet market demands, but butadiene products cannot be provided in the new energy field, coal chemical industry and large-scale shale gas development, so people pay attention to other butadiene production methods, and research on butylene oxidative dehydrogenation technology is wide.

The carbon four-fraction of the refinery contains a large amount of butylene, the carbon four-fraction has low use added value as civil fuel, and the high-selectivity conversion of the butylene into butadiene has obvious economic benefit and has important significance for the comprehensive utilization of carbon four-fraction resources. The process route for producing butadiene by oxidative dehydrogenation of butylene has great application prospect.

The catalysts currently used in the industrial production of butadiene by oxidative dehydrogenation of butene can be mainly classified into the following two types: bismuth molybdate systems and ferrite systems. The bismuth molybdate system catalyst is a multi-component catalyst based on Mo-Bi oxide. The main disadvantage of the bismuth molybdate catalyst used for preparing butadiene by oxidative dehydrogenation of butylene is that the byproduct contains oxide, especially oxideThe organic acid has more amount and the three wastes are seriously polluted. In the molybdenum series composite oxide catalyst, the main reaction for removing butylene from oxidative dehydrogenation to butadiene and the complete combustion to generate CO₂In addition to the side reactions, 8-10% of the butenes are converted into oxidation products such as furan, aldehyde, ketone, acid, etc. This problem is particularly acute today where clean production is currently of increasing importance. Having a spinel structure (A)²⁺B₂ ³⁺O₄) Ferrite catalysts such as ZnFe₂O₄、MnFe₂O₄、MgFe₂O₄、ZnCrFeO₄And Mg_0.1Zn_0.9Fe₂O₄The method has the advantages of high activity and selectivity for oxidative dehydrogenation of butene, less oxygen-containing byproducts, long service life, high economic benefit, less three-waste pollution and the like. The butylene is oxidized and dehydrogenated on the catalyst, the conversion rate can reach more than 70 percent, and the selectivity can reach more than 90 percent. The ferrite catalyst with a spinel structure has better effect in the reaction of preparing butadiene by oxidative dehydrogenation of butylene (CN 105521796A, CN103102238A, CN103079695A and the like).

The Oxo-D process of the TPC group of the United states (formerly Texas Petrochemical) and the O-X-D process of Philips of the United states are typical processes for preparing butadiene through oxidative dehydrogenation of butene. The Oxo-D process adopts mixed feeding of butylene, water vapor and air, and carries out dehydrogenation reaction on an iron catalyst bed layer, wherein the reaction temperature is 550-600 ℃, the selectivity of butadiene is about 93 percent, and the conversion rate of butylene reaches 65 percent. In the O-X-D process, butylene, water vapor and air are used for carrying out oxidative dehydrogenation reaction in a fixed bed reactor, the reaction temperature is 480-600 ℃, the conversion rate of butylene is 75-80%, and the selectivity of butadiene is 88-92%.

The existing production process for preparing butadiene by oxidative dehydrogenation of butylene still has the problems of serious deep oxidation reaction and low butadiene selectivity. In order to make the process route for preparing butadiene by oxidative dehydrogenation of butene more competitive, it is necessary to improve the butadiene selectivity of the catalyst.

Disclosure of Invention

The invention aims to solve the technical problem that the selectivity of butadiene is low in the existing production process of preparing butadiene by oxidative dehydrogenation of butylene, and provides a novel catalyst for preparing butadiene by oxidative dehydrogenation of butylene. The second technical problem to be solved by the present invention is to provide a method for preparing a catalyst corresponding to the first technical problem, wherein the method for preparing the catalyst is simple. The third technical problem to be solved by the invention is to provide a process method for preparing butadiene by oxidative dehydrogenation of butylene, which corresponds to one of the technical problems to be solved, and the butadiene product is efficiently and stably prepared in the oxidative dehydrogenation reaction of butylene, and the process method has the advantages of high butadiene selectivity and high catalyst stability.

In order to solve the first technical problem, the technical scheme adopted by the invention is as follows: a catalyst for preparing butadiene by oxidative dehydrogenation of butylene is prepared from CO at 400-500 deg.C₂The adsorption capacity is larger than that of CO at room temperature ₂10% of the saturated adsorption amount.

In the above technical solution, the catalyst for preparing butadiene by oxidative dehydrogenation of butene comprises a) M in spinel structure^IIFe₂O₄Is a main active component, wherein M is at least one selected from the group consisting of Zn, Mg, Mn, Co and Ni.

b) With the structural general formula A_aB_bC_cO_xIn a molar ratio with M as an auxiliary^IIFe₂O₄Has the chemical formula of M^IIFe₂O₄·A_aB_bC_cO_xThe catalyst of (1), wherein:

a is selected from Fe; b is selected from P; c is at least one selected from halogen elements; the value range of a is 0.01-2;

the value range of b is 0.01-1;

the value range of c is 0.001-0.1;

x is the total number of oxygen atoms required to satisfy the valence state of each element in the catalyst.

In the above-mentioned embodiment, the divalent metal M is preferably selected from at least one of Zn and Mg.

In the above technical scheme, preferably, the value range of a is 0.05-0.5.

In the above technical scheme, preferably, the value range of b is 0.01-0.5.

In the above technical scheme, preferably, the value range of c is 0.005-0.05.

In the above-mentioned embodiment, the halogen element is preferably at least one selected from Cl and Br.

In the above technical solution, preferably, the catalyst contains CO₂CO at 400-450 ℃ on a temperature programmed desorption spectrogram₂The adsorption capacity is larger than that of CO at room temperature ₂20% of saturated adsorption capacity; more preferably, the CO of the catalyst₂CO at 400-450 ℃ on a temperature programmed desorption spectrogram₂The adsorption capacity is larger than that of CO at room temperature₂25% of the saturated adsorption amount.

In order to solve the second technical problem, the preparation method of the catalyst for preparing butadiene by oxidative dehydrogenation of butene comprises the following steps:

1) mixing at least one of a group consisting of a source of Fe, a source of P, and a source of Zn, Mg, Co, Mn or Ni with at least one of a halogen element to obtain a catalyst precursor;

2) shaping a mixture comprising a catalyst precursor and optionally added pore-forming agent to obtain the catalyst;

3) optionally, the catalyst further comprises the steps of drying and roasting.

In the above technical solution, the volume average particle diameter of the catalyst precursor is less than 100 μm, and D (0.97) (volume particle diameter) is less than 200 μm. Wherein D (0.97) (volume particle size) means that 97% of the particles in the catalyst precursor all have a volume particle size within a certain particle size range.

The volume average particle size of the catalyst precursor was determined using a Mastersizer 2000 laser particle sizer with particle size measurements ranging from 0.02 to 2000 microns. The particle size of the catalyst precursor was measured by a wet method, the dispersant was water during the test, the refractive index of the dispersant was 1.33, the test conditions were high-speed stirring and ultrasonic dispersion, and the test results were analyzed by a general analysis mode.

In the technical scheme, the drying temperature of the catalyst is 90-150 ℃, the drying time is 1-24 hours, the roasting temperature is 450-850 ℃, and the roasting time is 1-24 hours.

In the above technical scheme, preferably, Fe in the precursor of the catalyst can be added in the form of red iron oxide or/and yellow iron oxide; zn, Mg, Mn, Co and Ni are added in the form of oxides or hydroxides or salts; the halogen element is added in the form of inorganic salt; p is added in the form of oxide or phosphate; besides the main component of the catalyst, a pore-forming agent can be optionally added, and the pore-forming agent can be selected from graphite, sesbania powder and polystyrene microspheres.

In order to solve the technical problem III, the reaction of the technical method for preparing butadiene by oxidative dehydrogenation of butene comprises the step of contacting the butene with a catalyst in the presence of oxygen-containing gas, wherein the oxygen-containing gas comprises air, oxygen or O₂With CO₂At least one of the mixtures of (a).

In the technical scheme, water is preheated to be water vapor before entering the reactor and is fully mixed with the raw material gas.

In the above technical scheme, the butene in the reactants: oxygen: the volume ratio of water vapor is 1: (0.1-20): (1-20), and the temperature of a reaction inlet is 300-500 ℃.

In the above technical solution, preferably, the oxygen is O₂With CO₂In the mixture of (A) and (B)₂And CO₂In a molar ratio of 1: (0.1 to 100).

Compared with the prior art, the invention has obvious advantages and outstanding effects. The main by-product of ferrite-type catalysts in the oxidative dehydrogenation of butenes is the deep oxide CO₂The selectivity is usually above 7%, resulting in low butadiene selectivity and large greenhouse gas emissions. The catalyst adopted by the invention and the combined auxiliary agent thereof improve CO₂The desorption temperature of the catalyst still has proper CO on the surface of the catalyst within the temperature range (350-500 ℃) of the oxidative dehydrogenation reaction of the butylene₂The adsorption amount is increased, thereby covering partial deep oxidation reaction center and inhibiting CO₂The selectivity of the target product butadiene is improved. Adsorbed CO₂Can be produced from the reaction itself. At the same time, brineThe element, the P element and the like also adjust the acidity and alkalinity of the surface of the catalyst, and promote the adsorption of alkaline butylene molecules on the surface of the catalyst, thereby improving the reaction activity of the catalyst. The catalyst has the advantages of high butadiene selectivity, high catalyst activity and high stability. The catalyst is prepared by adopting a mechanical mixing method, the process is simple and easy to control, the problems of large wastewater discharge amount, low yield, complex process and the like in the traditional coprecipitation preparation method are solved, and the catalyst has the advantages of environmental protection, energy conservation, high yield and stable performance. By controlling the particle size of the catalyst precursor, the full generation of the active crystal phase of the catalyst and the uniform dispersion of each component are ensured, thereby ensuring the performance of the catalyst.

The butylene oxidative dehydrogenation reaction is carried out on a micro catalytic reaction device of a continuous flow quartz tube reactor. Analysis of products the contents of alkane, alkene, butadiene, etc. in the dehydrogenated product were analyzed on-line using HP-5890 gas chromatograph (HP-AL/S capillary column, 50 m.times.0.53 mm.times.15 μm; FID detector) and the conversion of the reaction and the product selectivity were calculated. The catalyst prepared by the method has good catalytic activity when used for butylene oxidative dehydrogenation, the butadiene selectivity can reach 97%, the stability is high, and a good technical effect is achieved.

The invention is further illustrated by the following examples.

Drawings

FIG. 1, CO of catalyst₂Temperature programmed desorption diagram, percentage is CO of catalyst under different temperatures₂Adsorption capacity and CO at room temperature₂Saturated adsorption amount ratio. Wherein A is the example catalyst and B is the comparative catalyst

FIG. 2 is a schematic view showing the particle size distribution of the catalyst precursor

Detailed Description

[ example 1 ]

Weighing appropriate amount of iron oxide red, MgO and MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 41 μm and a volume particle diameter D (0.97) (volume particle diameter) of 90 μm. Adding appropriate amount of graphite and water into the mixture, and stirring in a kneader for 2 hoursThe extruded strand was removed and the resulting solid was dried in an oven at 110 ℃ for 4 hours. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 1 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂47% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂26% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂13% of the saturated adsorption amount. The molar ratio of the elemental composition of catalyst 1 was MgFe₂O₄·Fe_0.2P_0.05Cl_0.01O_x。

[ example 2 ]

Weighing proper amounts of iron oxide yellow, MgO and MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 45 μm and a volume particle diameter D (0.97) (volume particle diameter) of 98 μm. And adding a proper amount of sesbania powder and water into the mixture, stirring the mixture in a kneader for 1 hour, taking out the mixture, extruding the mixture into strips, and drying the obtained solid in an oven at 90 ℃ for 24 hours. And roasting the dried sample in a muffle furnace at 460 ℃ for 24 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 2 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂49% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂28% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂15% of the saturated adsorption amount. The molar ratio of the element composition of the catalyst 2 is MgFe₂O₄·Fe_0.02P_0.05Cl_0.01O_x。

[ example 3 ]

Weighing appropriate amount of iron oxide yellow, Mg (OH)₂、MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 39 μm and a volume particle diameter D (0.97) (volume particle diameter) of 85 μm. And adding a proper amount of polystyrene microspheres and water into the mixture, stirring the mixture in a kneader for 10 hours, taking out the mixture, extruding the mixture into strips, and drying the obtained solid in an oven at 150 ℃ for 1 hour. Roasting the dried sample in a muffle furnace at 850 ℃ for 1 hour, and grinding the roasted sample into particles of 40-60 meshes for catalysisAnd (4) evaluating the reagent. Catalyst 3 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂48% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂27% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂The saturated adsorption amount was 14%. The molar ratio of the elemental composition of catalyst 3 is MgFe₂O₄·Fe_0.05P_0.05Cl_0.01O_x。

[ example 4 ]

Weighing appropriate amount of iron oxide red, MgO and FeCl₃And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 37 μm and a volume particle diameter D (0.97) (volume particle diameter) of 82 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 600 ℃ for 10 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 4 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂45% of saturated adsorption amount of CO at 450 DEG C₂The adsorption capacity is room temperature CO₂25% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂The saturated adsorption amount was 12%. The molar ratio of the elemental composition of catalyst 4 is MgFe₂O₄·Fe_0.5P_0.05Cl_0.01O_x。

[ example 5 ]

Weighing appropriate amount of iron oxide red, MgO and MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 40 μm and a volume particle diameter D (0.97) (volume particle diameter) of 88 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 600 ℃ for 10 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 5 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂44% of saturated adsorption amount of CO at 450 DEG C₂The adsorption capacity is room temperature CO₂The saturated adsorption capacity is 24 percent and is at 500 DEG CCO of₂The adsorption capacity is room temperature CO₂The saturated adsorption amount was 11%. The molar ratio of the elemental composition of the catalyst 5 is MgFe₂O₄·Fe_2.0P_0.05Cl_0.01O_x。

[ example 6 ]

Weighing appropriate amount of iron oxide red, MgO and MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 51 μm and a volume particle diameter of D (0.97) (volume particle diameter) of 110 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 6 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂46% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂25% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂The saturated adsorption amount was 12%. The molar ratio of the elemental composition of the catalyst 6 is MgFe₂O₄·Fe_0.2P_0.01Cl_0.01O_x。

[ example 7 ]

Weighing appropriate amount of iron oxide red, MgO and MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 46 μm and a volume particle diameter D (0.97) (volume particle diameter) of 100 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. CO of catalyst 7 at 400 deg.C₂The adsorption capacity is room temperature CO₂48% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂28% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂15% of the saturated adsorption amount. The molar ratio of the elemental composition of catalyst 7 was MgFe₂O₄·Fe_0.2P_0.5Cl_0.01O_x。

[ example 8 ]

Weighing appropriate amount of iron oxide red, MgO and MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 42 μm and a volume particle diameter of D (0.97) (volume particle diameter) of 92 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 8 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂52% of saturated adsorption amount of CO at 450 DEG C₂The adsorption capacity is room temperature CO₂Saturated adsorption of 31% of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂18% of the saturated adsorption amount. The molar ratio of the elemental composition of catalyst 8 is MgFe₂O₄·Fe_0.2P_1.0Cl_0.01O_x。

[ example 9 ]

Weighing appropriate amount of iron oxide red, MgO and MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 52 μm and a volume particle diameter D (0.97) (volume particle diameter) of 116 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 9 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂41% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂21% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO ₂10% of the saturated adsorption amount. The molar ratio of the elemental composition of catalyst 9 was MgFe₂O₄·Fe_0.2P_0.05Cl_0.001O_x。

[ example 10 ]

Weighing appropriate amount of iron oxide red, MgO and MgCl₂And magnesium phosphate, crushing and screening to obtain the product with flat volumeThe catalyst precursor had a mean particle diameter of 38 μm and a D (0.97) (volume particle diameter) of 86 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 10 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂45% of saturated adsorption amount of CO at 450 DEG C₂The adsorption capacity is room temperature CO₂Saturated adsorption of 23% of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂The saturated adsorption amount was 11%. The molar ratio of the elemental composition of catalyst 10 is MgFe₂O₄·Fe_0.2P_0.05Cl_0.005O_x。

[ example 11 ]

Weighing appropriate amount of iron oxide red, MgO and MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 45 μm and a volume particle diameter D (0.97) (volume particle diameter) of 102 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 11 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂49% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂29% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂The saturated adsorption amount was 16%. The molar ratio of the elemental composition of catalyst 11 is MgFe₂O₄·Fe_0.2P_0.05Cl_0.05O_x。

[ example 12 ]

Weighing appropriate amount of iron oxide red, MgO and MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 49 μm and a volume particle diameter of D (0.97) (volume particle diameter) of 109 μm. Adding appropriate amount of graphite and water into the mixture, stirring in a kneader for 2 hours, taking out, extruding to form, and placing the obtained solid in an ovenDried at 110 ℃ for 4 hours. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. CO of catalyst 12 at 400 deg.C₂The adsorption capacity is room temperature CO₂Saturated adsorption of 53% CO at 450 ℃₂The adsorption capacity is room temperature CO₂32% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂The saturated adsorption amount was 19%. The molar ratio of the elemental composition of catalyst 12 is MgFe₂O₄·Fe_0.2P_0.05Cl_0.1O_x。

[ example 13 ]

Weighing appropriate amount of iron oxide red, MgO and MgBr₂、MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 60 μm and a volume particle diameter D (0.97) (volume particle diameter) of 140 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 13 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂46% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂26% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂13% of the saturated adsorption amount. The molar ratio of the elemental composition of the catalyst 13 is MgFe₂O₄·Fe_0.2P_0.05Cl_0.005Br_0.005O_x。

[ example 14 ]

Weighing appropriate amount of iron oxide red, MgO and MgBr₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 53 μm and a volume particle diameter of D (0.97) (volume particle diameter) of 110 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 14 was at 400 deg.CCO of₂The adsorption capacity is room temperature CO₂45% of saturated adsorption amount of CO at 450 DEG C₂The adsorption capacity is room temperature CO₂25% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂The saturated adsorption amount was 12%. The elemental composition molar ratio of catalyst 14 is MgFe₂O₄·Fe_0.2P_0.05Br_0.01O_x。

[ example 15 ]

Weighing appropriate amount of iron oxide red, MgO and MgI₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 47 μm and a volume particle diameter D (0.97) (volume particle diameter) of 104 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 15 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂44% of saturated adsorption amount of CO at 450 DEG C₂The adsorption capacity is room temperature CO₂Saturated adsorption of 23% of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂The saturated adsorption amount was 11%. The molar ratio of the elemental composition of the catalyst 15 is MgFe₂O₄·Fe_0.2P_0.05I_0.01O_x。

[ example 16 ]

Weighing appropriate amount of iron oxide red, ZnO and FeCl₃And zinc phosphate were pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 35 μm and a volume particle diameter D (0.97) (volume particle diameter) of 80 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 16 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂45% of saturated adsorption amount of CO at 450 DEG C₂The adsorption capacity is room temperature CO₂25% of saturated adsorption amount of CO at 500 deg.C₂Adsorption capacity of the chamberWarm CO₂The saturated adsorption amount was 12%. The molar ratio of the elemental composition of the catalyst 16 is ZnFe₂O₄·Fe_0.2P_0.05Cl_0.01O_x。

[ example 17 ]

Weighing appropriate amount of iron oxide red, MgO, ZnO and MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 42 μm and a volume particle diameter of D (0.97) (volume particle diameter) of 96 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 17 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂46% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂26% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂13% of the saturated adsorption amount. The molar ratio of the elemental composition of catalyst 17 is Mg_0.9Zn_0.1Fe₂O₄·Fe_0.2P_0.05Cl_0.01O_x。

[ example 18 ]

Weighing appropriate amount of iron oxide red, MgO, ZnO and MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 44 μm and a volume particle diameter D (0.97) (volume particle diameter) of 98 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 18 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂45% of saturated adsorption amount of CO at 450 DEG C₂The adsorption capacity is room temperature CO₂Saturated adsorption of 24% CO at 500 deg.C₂The adsorption capacity is room temperature CO₂The saturated adsorption amount was 11%. The molar ratio of the elemental composition of catalyst 18 is Mg_0.1Zn_0.9Fe₂O₄·Fe_0.2P_0.05Cl_0.01O_x。

[ example 19 ]

Weighing appropriate amount of iron oxide red, MgO, ZnO and MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 53 μm and a volume particle diameter of D (0.97) (volume particle diameter) of 127 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 19 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂46% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂25% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂The saturated adsorption amount was 12%. Catalyst 19 has an elemental composition in a molar ratio of Mg_0.5Zn_0.5Fe₂O₄·Fe_0.2P_0.05Cl_0.01O_x。

[ example 20 ]

Weighing appropriate amount of iron oxide red, MgO, Co (OH)₂、MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 78 μm and a volume particle diameter of D (0.97) (volume particle diameter) of 153 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 20 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂48% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂27% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂The saturated adsorption amount was 14%. The molar ratio of the elemental composition of catalyst 20 is Mg_0.9Co_0.1Fe₂O₄·Fe_0.2P_0.05Cl_0.01O_x。

[ example 21 ]

Weighing appropriate amount of iron oxide red, MgO, MnO and MgCl₂And magnesium phosphate, and the mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 86 μm and a volume particle diameter of D (0.97) (volume particle diameter) of 181 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Catalyst 21 CO at 400 deg.C₂The adsorption capacity is room temperature CO₂46% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂Saturated adsorption of 23% of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂The saturated adsorption amount was 11%. The molar ratio of the elemental composition of catalyst 21 is Mg_0.9Mn_0.1Fe₂O₄·Fe_0.2P_0.05Cl_0.01O_x。

Comparative example 1

The catalyst was prepared according to comparative document CN 105521796A. An appropriate amount of ferric nitrate (Fe (NO) was weighed₃)₃·9H₂O), zinc nitrate (Zn (NO)₃)₂·6H₂O), magnesium nitrate (Mg (NO)₃)₂·6H₂O), chromium nitrate (Cr (NO)₃)₃·9H₂O), manganese nitrate (Mn (NO)₃)₂·4H₂O), ammonium metavanadate (NH)₄VO₃) Antimony chloride (SbCl)₃) Cerium nitrate (Ce (NO)₃)₃·6H₂O), gallium nitrate (Ga (NO)₃)₃) And indium nitrate (In (NO)₃)₃) Dissolved in 5L of distilled water and stirred uniformly to form a solution. Then, the above solution was coprecipitated with a 20% aqueous ammonia solution, the pH of the precipitate was maintained at 9.5, the precipitation temperature was room temperature, then a solid sample in the precipitated product was separated by a centrifugal separator, washed with 5L of distilled water, and the resulting solid was dried in an oven at 110 ℃ for 4 hours. The dried sample was further calcined in a muffle furnace at 600 ℃ for 4 hours to obtain the catalyst of comparative example 1, and the catalyst was ground into particles of 40-60 mesh for catalyst evaluation. Comparative example 1 catalyst at 40CO at 0 deg.C₂The adsorption capacity is room temperature CO ₂22% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂7% of saturated adsorption amount of CO at 500 deg.C₂The adsorption capacity is room temperature CO ₂1% of the saturated adsorption amount. Comparative example 1 the catalyst had a molar ratio of elemental composition of Fe₁₀Zn_1.5Mg_2.0Cr_0.2Mn_0.1V_0.08Sb_0.3Ce_0.2Ga_0.1In_0.2O_x。

Comparative example 2

Weighing appropriate amounts of iron oxide Red and Mg (OH)₂The resulting mixture was pulverized and sieved to obtain a catalyst precursor having a volume average particle diameter of 60 μm and a volume particle diameter of D (0.97) (volume particle diameter) of 131 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Comparative example 2 catalyst CO at 400 ℃₂The adsorption capacity is room temperature CO₂Saturated adsorption of 16% of CO at 450 ℃₂The adsorption capacity is room temperature CO₂Saturated adsorption of 5% of CO at 500 deg.C₂The adsorption capacity is room temperature CO₂0.7% of the saturated adsorption amount. Comparative example 2 the molar ratio of the elemental composition of the catalyst was MgFe₂O₄。

Comparative example 3

Appropriate amounts of red iron oxide and MgO were weighed, pulverized, and sieved to obtain a catalyst precursor having a volume average particle size of 58 μm and a volume particle size of D (0.97) (volume particle size) of 126 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Comparative example 3 catalyst CO at 400 deg.C₂The adsorption capacity is room temperature CO₂Saturated adsorption of 14% of CO at 450 ℃₂The adsorption capacity is room temperature CO₂Saturated adsorption of 4% of CO at 500 deg.C₂Adsorption capacity of the chamberWarm CO₂0.5% of the saturated adsorption amount. Comparative example 3 the molar ratio of the elemental composition of the catalyst was MgFe₂O₄·Fe_0.2O_x。

Comparative example 4

Appropriate amounts of red iron oxide, MgO and magnesium phosphate were weighed, pulverized and sieved, to obtain a catalyst precursor having a volume average particle size of 49 μm and a volume particle size D (0.97) (volume particle size) of 110 μm. And adding a proper amount of graphite and water into the mixture, stirring the mixture in a kneader for 2 hours, taking out the mixture, extruding the mixture into strips, forming the strips, and drying the obtained solid in an oven for 4 hours at 110 ℃. And roasting the dried sample in a muffle furnace at 700 ℃ for 6 hours, and grinding the roasted sample into particles of 40-60 meshes for catalyst evaluation. Comparative example 4 catalyst CO at 400 deg.C₂The adsorption capacity is room temperature CO₂23% of saturated adsorption amount of CO at 450 deg.C₂The adsorption capacity is room temperature CO₂Saturated adsorption of 8% of CO at 500 deg.C₂The adsorption capacity is room temperature CO ₂2% of the saturated adsorption amount. Comparative example 4 the molar ratio of the elemental composition of the catalyst was MgFe₂O₄·Fe_0.2P_0.05O_x。

[ example 22 ]

0.5g of the catalysts of examples 1 to 21 and comparative examples 1 to 4 were used for evaluation of oxidative dehydrogenation of butene. The feed gas is a mixture of butylene, oxygen and water vapor, wherein the ratio of butylene: oxygen: the composition molar ratio of water is 1: 0.68: 12. the raw material gas is fully mixed and then introduced into a reactor for oxidative dehydrogenation. The inlet temperature of the reactor is 380 ℃; the reaction pressure is normal pressure; the mass space velocity of the butylene is 0.6h^-1. The catalytic reaction was carried out under the above conditions, and the reaction product was analyzed by gas chromatography. The reaction results are shown in Table 1.

TABLE 1

Butene conversion and butadiene selectivity over 10 hours of reaction

**A₄₀₀/A_rt: CO at 400 ℃ for the catalyst₂Adsorption capacity and CO at room temperature₂Proportion of saturated adsorption amount

D (v): volume average particle diameter of the catalyst precursor.

Claims

1. A catalyst for preparing butadiene by oxidative dehydrogenation of butylene is prepared from CO at 400-500 deg.C₂The adsorption capacity is larger than that of CO at room temperature₂10% of the saturated adsorption amount.

2. The catalyst of claim 1 for the oxidative dehydrogenation of butene to butadiene, the catalyst comprising M^IIFe₂O₄Is a main active component, wherein M is at least one selected from the group consisting of Zn, Mg, Mn, Co and Ni.

3. The catalyst for preparing butadiene by oxidative dehydrogenation of butene according to claim 2, which comprises the main active component M^IIFe₂O₄Is of spinel structure.

4. The catalyst of claim 2 for the oxidative dehydrogenation of butene to butadiene, further comprising a catalyst having the general structural formula A_aB_bC_cO_xIn a molar ratio with M as an auxiliary^IIFe₂O₄Has the chemical formula of M^IIFe₂O₄·A_aB_bC_cO_xThe catalyst of (1), wherein:

a is selected from Fe; b is selected from P; c is at least one selected from halogen elements;

the value range of a is 0.01-2;

the value range of b is 0.01-1;

the value range of c is 0.001-0.1;

5. The catalyst for the oxidative dehydrogenation of butene to butadiene according to claim 2, wherein M is at least one selected from the group consisting of Zn and Mg.

6. The catalyst for preparing butadiene through oxidative dehydrogenation of butene according to claim 4, wherein a is 0.05-0.5, b is 0.01-0.5, and c is 0.005-0.05.

7. The catalyst for the oxidative dehydrogenation of butene to butadiene according to claim 4, wherein said halogen element is at least one selected from the group consisting of Cl or Br.

8. The catalyst for preparing butadiene through oxidative dehydrogenation of butene according to claim 1, wherein the catalyst has a CO content of 400-450 ℃₂The adsorption capacity is larger than that of CO at room temperature₂20% of saturated adsorption amount, preferably 400-450 deg.C CO₂The adsorption capacity is larger than that of CO at room temperature₂25% of the saturated adsorption amount.

9. A preparation method of a catalyst for preparing butadiene by oxidative dehydrogenation of butylene is characterized by comprising the following steps:

3) optionally, the catalyst further comprises the steps of drying and roasting.

10. The method for preparing a catalyst according to claim 9, characterized in that the volume average particle diameter of the catalyst precursor is <100 μm, and D (0.97) (volume particle diameter) <200 μm.

11. The method for preparing the catalyst according to claims 8 to 9, wherein the drying temperature is 90 ℃ to 150 ℃, the drying time is 1 to 24 hours, the calcination temperature is 450 ℃ to 850 ℃, and the calcination time is 1 to 24 hours.

12. A process for preparing butadiene by oxidative dehydrogenation of butene using the catalyst of any one of claims 1 to 11, characterized in that the reaction comprises a step of contacting butene with the catalyst in the presence of an oxygen-containing gas comprising air, oxygen or O₂With CO₂At least one of the mixtures of (a).

13. The process of claim 12 wherein the ratio of butene: oxygen: the volume ratio of water vapor is 1: (0.1-20): (1-20), and the temperature of a reaction inlet is 300-500 ℃.

14. The process of claim 12, said O₂With CO₂In the mixture of (A) and (B)₂And CO₂In a molar ratio of 1: (0.1 to 100).