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CN110614115A - Isobutane dehydrogenation catalyst with spherical tri-mesoporous composite material as carrier and preparation method and application thereof - Google Patents

Isobutane dehydrogenation catalyst with spherical tri-mesoporous composite material as carrier and preparation method and application thereof Download PDF

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Publication number
CN110614115A
CN110614115A CN201810638996.7A CN201810638996A CN110614115A CN 110614115 A CN110614115 A CN 110614115A CN 201810638996 A CN201810638996 A CN 201810638996A CN 110614115 A CN110614115 A CN 110614115A
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China
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mesoporous
isobutane
filter cake
dehydrogenation catalyst
carrier
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亢宇
刘红梅
刘东兵
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Sinopec Beijing Research Institute of Chemical Industry
China Petroleum and Chemical Corp
China Petrochemical Corp
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Sinopec Beijing Research Institute of Chemical Industry
China Petrochemical Corp
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Priority to CN201810638996.7A priority Critical patent/CN110614115A/en
Publication of CN110614115A publication Critical patent/CN110614115A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J29/00—Catalysts comprising molecular sieves
    • B01J29/03—Catalysts comprising molecular sieves not having base-exchange properties
    • B01J29/0308—Mesoporous materials not having base exchange properties, e.g. Si-MCM-41
    • B01J29/0316—Mesoporous materials not having base exchange properties, e.g. Si-MCM-41 containing iron group metals, noble metals or copper
    • B01J29/0325—Noble metals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J35/61—Surface area
    • B01J35/615—100-500 m2/g
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J35/61—Surface area
    • B01J35/617—500-1000 m2/g
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J35/63—Pore volume
    • B01J35/635—0.5-1.0 ml/g
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J35/63—Pore volume
    • B01J35/638—Pore volume more than 1.0 ml/g
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J35/64—Pore diameter
    • B01J35/647—2-50 nm
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J35/66—Pore distribution
    • B01J35/695—Pore distribution polymodal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/0009—Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
    • B01J37/0018—Addition of a binding agent or of material, later completely removed among others as result of heat treatment, leaching or washing,(e.g. forming of pores; protective layer, desintegrating by heat)
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/0201—Impregnation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/08—Heat treatment
    • B—PERFORMING OPERATIONS; TRANSPORTING
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    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/08—Heat treatment
    • B01J37/10—Heat treatment in the presence of water, e.g. steam
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C5/00—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms
    • C07C5/32—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms by dehydrogenation with formation of free hydrogen
    • C07C5/327—Formation of non-aromatic carbon-to-carbon double bonds only
    • C07C5/333—Catalytic processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
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    • B01J2229/00—Aspects of molecular sieve catalysts not covered by B01J29/00
    • B01J2229/10—After treatment, characterised by the effect to be obtained
    • B01J2229/18—After treatment, characterised by the effect to be obtained to introduce other elements into or onto the molecular sieve itself
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
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  • Dispersion Chemistry (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
  • Catalysts (AREA)
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Abstract

The invention relates to the field of catalysts, and discloses an isobutane dehydrogenation catalyst with a spherical tri-mesoporous composite material as a carrier, and a preparation method and application thereof. The method comprises the following steps: (a) preparing a No. 1 mesoporous material filter cake and a No. 2 mesoporous material filter cake; (b) preparing a silica gel filter cake; (c) preparing a spherical tri-mesoporous composite material carrier; (d) and (c) dipping the spherical tri-mesoporous composite material carrier obtained in the step (c) in a solution containing a Pt component precursor and a Zn component precursor, and then sequentially carrying out solvent removal treatment, drying and roasting. The method can synthesize the isobutane dehydrogenation catalyst with high catalytic activity by utilizing the silicon source with low cost.

Description

Isobutane dehydrogenation catalyst with spherical tri-mesoporous composite material as carrier and preparation method and application thereof
Technical Field
The invention relates to the field of catalysts, in particular to an isobutane dehydrogenation catalyst with a spherical tri-mesoporous composite material as a carrier, a preparation method thereof, an isobutane dehydrogenation catalyst prepared by the method and application of the isobutane dehydrogenation catalyst in preparation of isobutene through isobutane dehydrogenation.
Background
Isobutene is an important organic chemical raw material and is mainly used for preparing various organic raw materials and fine chemicals such as methyl tert-butyl ether, butyl rubber, methyl ethyl ketone, polyisobutylene, methyl methacrylate, isoprene, tert-butyl phenol, tert-butyl amine, 1, 4-butanediol, ABS resin and the like. The main sources of isobutene are the by-product C4 fraction from an apparatus for producing ethylene by steam cracking of naphtha, the by-product C4 fraction from a refinery Fluid Catalytic Cracking (FCC) apparatus, and the by-product tert-butyl alcohol (TAB) in the synthesis of propylene oxide by the Halcon method.
In recent years, with the development and utilization of downstream products of isobutene, the demand of isobutene is increased year by year, and the traditional isobutene production cannot meet the huge demand of the chemical industry on isobutene, so the research and development work of a new isobutene production technology becomes a hot spot of the chemical industry. Among the most competitive technologies, isobutane dehydrogenation, n-butene skeletal isomerization and isobutene production by a novel FCC unit are known. Among the methods, the research on the reaction for preparing isobutene by directly dehydrogenating isobutane is early, and the industrial production is realized. China has abundant C4 resources, but the chemical utilization rate of C4 fraction is low in China, most of isobutane is directly used as fuel, and the waste is serious. The reasonable utilization of C4 resource is an urgent task in the petrochemical research field. Therefore, the isobutene prepared by dehydrogenating isobutane has a great development prospect in China.
The catalysts for preparing isobutene by isobutane dehydrogenation mainly comprise two types: oxide catalysts and noble metal catalysts. The oxide catalyst mainly comprises Cr2O3、V2O5、Fe2O3、MoO3ZnO, etc., and a composite oxide thereof, such as V-Sb-O, V-Mo-O, Ni-V-O, V-Nb-O, Cr-Ce-O, molybdate, etc. Compared with noble metal catalysts, oxide catalysts are less expensive. However, the catalyst is easy to deposit carbon, and the catalytic activity, selectivity and stability are low. In addition, most oxide catalysts contain components with high toxicity, which is not favorable for environmental protection. The research on dehydrogenation reactions on noble metal catalysts has a long history, and noble metal catalysts have higher activity, better selectivity, and are more environmentally friendly than other metal oxide catalysts. However, the catalyst cost is high due to the expensive price of noble metals, and the performance of such catalysts has not yet reached a satisfactory level.
In order to improve the reaction performance of the catalyst for preparing isobutene by isobutane dehydrogenation, researchers have done a lot of work. Such as: the catalyst performance is improved by changing the preparation method of the catalyst (industrial catalysis, 2014, 22(2): 148-. However, the specific surface area of the currently used carrier is small, which is not beneficial to the dispersion of the active metal component on the surface of the carrier, and is also not beneficial to the diffusion of raw materials and products in the reaction process.
Therefore, how to improve the reaction performance of the isobutane dehydrogenation catalyst is a problem to be solved in the field of preparing isobutene by isobutane dehydrogenation.
Disclosure of Invention
The invention aims to overcome the defects of uneven dispersion of noble metal active components and poor catalytic activity and stability of the existing isobutane dehydrogenation catalyst, and provides an isobutane dehydrogenation catalyst with a spherical tri-mesoporous composite material as a carrier, a preparation method thereof, an isobutane dehydrogenation catalyst prepared by the method and application of the isobutane dehydrogenation catalyst in preparation of isobutene by isobutane dehydrogenation.
In order to accomplish the above object, an aspect of the present invention provides a method for preparing an isobutane dehydrogenation catalyst, the method comprising the steps of:
(a) under the existence of a first template agent, trimethylpentane and ethanol, tetramethoxysilane is contacted with a first acid agent, and a product obtained after the contact is crystallized and filtered to obtain a No. 1 mesoporous material filter cake; in the presence of a second template agent, contacting tetraethoxysilane with a second acid agent, and crystallizing and filtering a mixture obtained after the contact to obtain a No. 2 mesoporous material filter cake;
(b) contacting water glass with inorganic acid, and filtering a product obtained after the contact to obtain a silica gel filter cake;
(c) mixing the No. 1 mesoporous material filter cake, the No. 2 mesoporous material filter cake and the silica gel filter cake, then sequentially filtering, washing and ball-milling the mixed material, pulping solid powder obtained after ball-milling with water, then performing spray drying, and removing the template agent from the obtained product to obtain a spherical tri-mesoporous composite material carrier;
(d) dipping the spherical tri-mesoporous composite material carrier obtained in the step (c) in a solution containing a Pt component precursor and a Zn component precursor, then sequentially carrying out solvent removal treatment, drying and roasting,
wherein, the filtration washing in the step (c) is carried out in a ceramic membrane filter, and the content of sodium ions in the mixed material after filtration washing is not higher than 0.2 percent by weight and the content of the template agent is not higher than 1 percent by weight calculated by sodium element.
A second aspect of the invention provides an isobutane dehydrogenation catalyst prepared by the aforementioned process.
The third aspect of the invention provides an application of the isobutane dehydrogenation catalyst prepared by the method in preparing isobutene through isobutane dehydrogenation, wherein the method for preparing isobutene through isobutane dehydrogenation comprises the following steps: isobutane was subjected to a dehydrogenation reaction in the presence of a catalyst and hydrogen.
After intensive research, the inventor of the invention finds that the carrier structure (including physical structures such as specific surface area, pore volume and pore size distribution, and chemical structures such as surface acid sites and electronic properties) of the noble metal catalyst not only has important influence on the dispersion degree of active metal components, but also directly influences mass transfer and diffusion in the reaction process. Thus, the catalytic properties of heterogeneous catalysts, such as activity, selectivity and stability, depend both on the catalytic characteristics of the active component and on the characteristics of the catalyst support. In order to reduce the content of noble metal in the catalyst as much as possible and improve the activity and stability of the catalyst at the same time, the preparation process of the carrier is of great importance. Most commercially available activated alumina has too many surface hydroxyl groups and too strong acidity. When the aluminum oxide is used as a carrier to prepare the dehydrogenation catalyst, the surface of the catalyst is easy to deposit carbon in the reaction process, and the rapid inactivation is caused.
The inventor of the invention discovers through research that the ceramic membrane filter is used for filtering and washing, the cross flow filtration is adopted, the flow rate of the membrane surface is higher in the filtration process, can reduce the accumulation of pollutants on the surface of the membrane, has higher membrane flux, directly mixes the mesoporous molecular sieve material prepared in the early stage with silica gel in a mobile phase state, filters and washes, has high separation efficiency and simple separation process, can obtain the spherical tri-mesoporous composite material carrier with a special pore structure without calcining again in the later stage to remove the template agent, the carrier has the characteristics of porous structure, large specific surface area and large pore volume, is favorable for the good dispersion of the noble metal component on the surface of the carrier, the prepared catalyst can achieve better dehydrogenation activity, selectivity, stability and anti-carbon deposition performance under the condition of low noble metal loading.
Compared with the prior art, the isobutane dehydrogenation catalyst prepared by the method provided by the invention has the following advantages:
(1) the method for preparing the isobutane dehydrogenation catalyst provided by the invention has the advantages of simple preparation process, easily controlled conditions and good product repeatability;
(2) the isobutane dehydrogenation catalyst prepared by the method provided by the invention can achieve better dehydrogenation activity, selectivity, stability and carbon deposition resistance under the condition of low loading of main active components (namely noble metals), and can effectively reduce the preparation cost of the isobutane dehydrogenation catalyst;
(3) in the isobutane dehydrogenation catalyst prepared by the method provided by the invention, the stability of a Zn center with an oxidized structure under a high-temperature reduction condition is very high, the inactivation of a single Pt component loaded on a carrier can be inhibited, carbon deposition is reduced, a strong acid center on the surface of the carrier is effectively neutralized, the surface of the carrier is free from acidity, and the dispersion degree of the Pt component is improved through a geometric effect, so that the carbon deposition risk in the reaction process of preparing isobutene by anaerobic dehydrogenation of isobutane can be remarkably reduced, the selectivity of a target product is improved, and the stability of the isobutane dehydrogenation catalyst is improved;
(4) the mesoporous molecular sieve material with the spherical shape, the larger specific surface area and the larger pore volume is synthesized by utilizing the silicon source with low cost, which is beneficial to the good dispersion of the noble metal component on the surface of the carrier, thereby ensuring that the isobutane catalyst is not easy to be inactivated due to the agglomeration of active metal particles in the reaction process;
(5) the isobutane dehydrogenation catalyst prepared by the method provided by the invention shows good catalytic performance when used for preparing isobutene by anaerobic dehydrogenation of isobutane, and has the advantages of high isobutane conversion rate, high isobutene selectivity, good catalyst stability and low carbon deposition.
Additional features and advantages of the invention will be set forth in the detailed description which follows.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:
FIG. 1 is an X-ray diffraction (XRD) spectrum of the spherical trimorous porous composite material of example 1;
FIG. 2 is an SEM scanning electron micrograph of the microstructure of the spherical tri-mesoporous composite material of example 1;
FIG. 3 is a pore size distribution graph of the spherical tri-mesoporous composite of example 1.
Detailed Description
The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.
As indicated previously, a first aspect of the present invention provides a process for the preparation of an isobutane dehydrogenation catalyst, the process comprising the steps of:
(a) under the existence of a first template agent, trimethylpentane and ethanol, tetramethoxysilane is contacted with a first acid agent, and a product obtained after the contact is crystallized and filtered to obtain a No. 1 mesoporous material filter cake; in the presence of a second template agent, contacting tetraethoxysilane with a second acid agent, and crystallizing and filtering a mixture obtained after the contact to obtain a No. 2 mesoporous material filter cake;
(b) contacting water glass with inorganic acid, and filtering a product obtained after the contact to obtain a silica gel filter cake;
(c) mixing the No. 1 mesoporous material filter cake, the No. 2 mesoporous material filter cake and the silica gel filter cake, then sequentially filtering, washing and ball-milling the mixed material, pulping solid powder obtained after ball-milling with water, then performing spray drying, and removing the template agent from the obtained product to obtain a spherical tri-mesoporous composite material carrier;
(d) dipping the spherical tri-mesoporous composite material carrier obtained in the step (c) in a solution containing a Pt component precursor and a Zn component precursor, and then sequentially carrying out solvent removal treatment, drying and roasting;
wherein, the filtration washing in the step (c) is carried out in a ceramic membrane filter, and the content of sodium ions in the mixed material after filtration washing is not higher than 0.2 percent by weight and the content of the template agent is not higher than 1 percent by weight calculated by sodium element.
According to the invention, the ceramic membrane filter is a set of precise super-filtration purification equipment which can be widely applied to various fields, the core component of the ceramic membrane filter is a microporous ceramic membrane filter tube, the ceramic membrane filter tube is formed by scientifically mixing various raw materials such as kaolin, zirconia and the like through the processes of biscuiting, crushing, grading, forming, pore forming, membrane making and the like, and the ceramic membrane filter tube has excellent thermal stability and pore stability, has high strength and chemical corrosion resistance, is suitable for precise filtration of various media, has good cleaning and regeneration performance, has double advantages of high-efficiency filtration and precise filtration, and can filter at the filtration rate of 5-10 m/s.
According to the invention, the filtration washing in step (c) is carried out in a ceramic membrane filter, said filtration washing being a fluid separation process in the form of "cross-flow filtration", in particular comprising: directly mixing the mesoporous molecular sieve material prepared in the step (a) with liquid silica gel in a liquid state, enabling the mixed raw material liquid to flow in a membrane tube at a high speed, taking the pressure difference on two sides of the membrane as a driving force according to different penetration rates of different molecular diameters of substances in a certain membrane aperture range, taking the membrane as a filtering medium, and under the driving action of certain pressure, obtaining clear penetrating fluid (water, inorganic salt Na) containing small molecular components+Small molecular liquid substances such as template agent and the like) penetrate through the membrane outwards along the vertical direction, turbid concentrated solution (suspended substances, glue, microorganisms and other macromolecular substances) containing macromolecular components is blocked on the outer surface or the inner surface of the membrane in a mechanical filtering, adsorbing and other modes, the filtering resistance is increased along with the extension of the filtering time, when the pressure difference reaches the preset back flushing pressure difference, the motor transmission and corresponding valves in the back flushing mechanism are started, the back flushing can be completed by adopting compressed air or water, and also can be realized by adopting purified liquid or solvent, and finally the fluid achieves the purposes of separation, concentration and purification.In the invention, the filtering and washing process is carried out at a filtering speed of 5-10m/s, the washing process needs to be supplemented continuously, the washing mode can be water washing and/or alcohol washing, for example, deionized water can be used for repeatedly washing and backwashing, then ethanol is used for repeatedly washing and backwashing, so as to reduce the sticky accumulation of pollutants on the surface of a membrane, improve the membrane flux, the respective washing times and backwashing times can be selected according to the actual experimental effect until the content of sodium ions in sodium element in the mixed material after filtering and washing in a membrane tube is not higher than 0.2 wt%, preferably 0.01-0.03 wt%, and the content of a template agent is not higher than 1 wt%, and finally the mixed material in the membrane tube is collected for subsequent treatment, so that the prepared spherical three-mesoporous composite material carrier can be directly used for preparing the isobutane dehydrogenation catalyst without subsequent calcination treatment to remove the template agent, simple operation and energy consumption saving. And when the ceramic membrane filter is adopted for filtering and washing, manual online operation is not needed, and time and labor are saved.
In the formation process of the isobutane dehydrogenation catalyst, the No. 1 mesoporous material filter cake is a mesoporous molecular sieve material with a one-dimensional hexagonal pore channel distribution structure; the No. 2 mesoporous material filter cake is a mesoporous molecular sieve material with a two-dimensional hexagonal pore channel distribution structure.
In the formation process of the isobutane dehydrogenation catalyst, the pore size distribution is controlled to be trimodal distribution mainly by controlling the composition of the No. 1 mesoporous material filter cake, the No. 2 mesoporous material filter cake and the silica gel filter cake, and the microstructure of the trimodal mesoporous composite material carrier is controlled to be spherical by controlling the forming method (i.e. firstly mixing and ball-milling the No. 1 mesoporous material filter cake, the No. 2 mesoporous material filter cake and the silica gel filter cake, then pulping the obtained solid powder with water and then spray-drying), so that the common easily-obtained raw materials can be used to synthesize the mesoporous molecular sieve material with the one-dimensional hexagonal pore channel distribution structure, the mesoporous molecular sieve material with the two-dimensional hexagonal pore channel distribution structure and the spherical trimodal composite material carrier with the advantages of the spherical carrier, wherein the carrier has the porous structure of the mesoporous molecular sieve material, has a large specific surface area, and has the advantages of the spherical carrier, The isobutane dehydrogenation catalyst with no acidity on the surface, good dehydrogenation activity, high selectivity, strong stability and good carbon deposition resistance can be prepared by dipping and processing the loaded Pt component and the loaded Zn component.
According to the invention, in the process of preparing the No. 1 mesoporous material filter cake and the No. 2 mesoporous material filter cake, the dosage of each substance can be selected and adjusted in a wide range. For example, in step (a), the molar ratio of the first template, ethanol, trimethylpentane and tetramethoxysilane may be 1: (100-500): (200-600): (50-200), preferably 1: (200-400): (250-400): (70-150); the molar ratio of the second template agent to the tetraethoxysilane can be 1: (1-2.5), preferably 1: (1-2).
According to the present invention, in order to make the obtained filter cake of the mesoporous material No. 1 have a one-dimensional hexagonal pore distribution structure, the kind of the first template is preferably triblock copolymer polyoxyethylene-polyoxypropylene-polyoxyethylene. Wherein the first template is commercially available (e.g., from Aldrich under the trade name P123, formula EO)20PO70EO20) It can also be prepared by various conventional methods. When the first template is polyoxyethylene-polyoxypropylene-polyoxyethylene, the number of moles of the template is calculated from the average molecular weight of polyoxyethylene-polyoxypropylene-polyoxyethylene.
According to the invention, in order to make the obtained filter cake of the No. 2 mesoporous material have a two-dimensional hexagonal pore channel distribution structure, the type of the second template agent is preferably Cetyl Trimethyl Ammonium Bromide (CTAB).
According to the invention, the first acid agent may be any acid or mixture of acids present. The acid or acid mixture may be used in pure form or in the form of an aqueous solution thereof, preferably in the form of an aqueous solution. Preferably, the first acid agent is a buffered solution of acetic acid and sodium acetate; more preferably, the first acidic agent has a pH of 1-6; further preferably, the first acidic agent has a pH of 3 to 5.
According to the present invention, the second acid agent may be any of various substances or mixtures (e.g., solutions) that can be conventionally used to adjust the pH. The second acid agent is preferably used in the form of an aqueous solution. Preferably, the second acid agent is a hydrochloric acid solution, and the pH value of the second acid agent is 0-1.
According to the present invention, the condition under which the tetramethoxysilane is contacted with the first acid agent may include: the temperature is 10-60 ℃, the time is 10-72 hours, and the pH value is 1-7; preferably, the condition for contacting the tetramethoxysilane with the first acid agent may include: the temperature is 10-30 deg.C, the time is 20-40 hr, and the pH value is 3-6. In order to further facilitate uniform mixing between the respective substances, the contact of the tetramethoxysilane with the first acid agent is preferably carried out under stirring conditions. The first acid agent is preferably used in an amount such that the pH of the reaction system in which the tetramethoxysilane and the first acid agent are contacted is 1 to 7, more preferably 3 to 6.
According to the present invention, the condition for contacting the tetraethoxysilane with the second acid agent may include: the temperature is 10-60 ℃, the time is 10-72 hours, and the pH value is 0-1; preferably, the condition for contacting the tetraethoxysilane and the second acid agent can comprise: the temperature is 30-150 ℃ and the time is 10-72 hours.
The crystallization conditions of the present invention may include: the temperature is 30-150 ℃ and the time is 10-72 hours, and preferably, the crystallization conditions comprise: the temperature is 40-80 ℃ and the time is 20-40 hours. The crystallization is carried out by a hydrothermal crystallization method.
In the present invention, the contact manner between the first template, ethanol, the first acid agent, trimethylpentane and tetramethoxysilane is not particularly limited, and for example, the five substances may be simultaneously mixed and contacted, or several of them may be mixed and contacted first, and the remaining substances may be added to the obtained mixture and then mixed and contacted continuously. Preferably, the contacting mode is that the first template agent, the ethanol, the first acid agent and the trimethylpentane are stirred and mixed at 10-100 ℃, then the tetramethoxysilane is added and the stirring and mixing are continued.
According to the method for preparing an isobutane dehydrogenation catalyst provided by the present invention, in the step (b), the conditions for contacting the water glass with the inorganic acid may include: the temperature can be 10-60 ℃, preferably 20-40 ℃; the time may be 1 to 5 hours, preferably 1.5 to 3 hours, and the pH value is 2 to 4. In order to further facilitate uniform mixing between the substances, the contact of the water glass with the mineral acid is preferably carried out under stirring conditions.
According to the invention, the water glass is an aqueous solution of sodium silicate conventional in the art, and its concentration may be 10 to 50% by weight, preferably 12 to 30% by weight.
According to the present invention, the inorganic acid may be one or more of sulfuric acid, nitric acid and hydrochloric acid. The inorganic acid may be used in a pure form or in the form of an aqueous solution thereof. The inorganic acid is preferably used in such an amount that the reaction system has a pH of 2 to 4 under the contact conditions of the water glass and the inorganic acid.
Preferably, in the presence of glycerol, for example, the method comprises: the water glass, the inorganic acid and the glycerol are contacted. Preferably, the weight ratio of the water glass, the inorganic acid and the glycerol can be (3-6): 1: 1. in order to further facilitate uniform mixing between the substances, the contact of the water glass, the inorganic acid and the glycerol is preferably carried out under stirring conditions.
In addition, in the above process for preparing the filter cake of the mesoporous material No. 1, the filter cake of the mesoporous material No. 2, and the filter cake of silica gel, the process for obtaining the filter cake by filtration may include: after filtration, washing with distilled water was repeated (the number of washing may be 2 to 10), followed by suction filtration. Preferably, the washing during the preparation of the filter cake of mesoporous material No. 2 is such that the pH of the filter cake is 7, and the washing during the preparation of the silica gel filter cake is such that the sodium ion content is less than 0.02 wt%.
According to the present invention, in the step (c), the amounts of the No. 1 mesoporous material filter cake, the No. 2 mesoporous material filter cake and the silica gel filter cake may be selected according to the components of the spherical tri-mesoporous composite material carrier to be obtained, and preferably, the amount of the silica gel filter cake may be 1 to 200 parts by weight, and preferably 50 to 150 parts by weight, based on 100 parts by weight of the total amount of the No. 1 mesoporous material filter cake and the No. 2 mesoporous material filter cake; the weight ratio of the No. 1 mesoporous material filter cake to the No. 2 mesoporous material filter cake can be 1: (0.1-10), preferably 1 (0.5-2).
According to the present invention, in step (c), the object of ball milling is a mixed material in the ceramic filter membrane tube which is filtered and washed by the ceramic membrane filter until the content of sodium ions calculated by sodium element is not higher than 0.2 wt%, preferably 0.01-0.03 wt%, and the content of the template agent is not higher than 1 wt%, and the specific operation method and conditions of ball milling are not particularly limited, based on that the structure of the mesoporous molecular sieve material is not destroyed or not substantially destroyed and silica gel enters the pore channels of the mesoporous molecular sieve material. One skilled in the art can select various suitable conditions to implement the present invention based on the above principles. Specifically, the ball milling is carried out in a ball mill, wherein the diameter of the milling balls in the ball mill can be 2-3 mm; the number of the grinding balls can be reasonably selected according to the size of the ball milling tank, and for the ball milling tank with the size of 50-150mL, 1 grinding ball can be generally used; the material of the grinding ball can be agate, polytetrafluoroethylene and the like, and agate is preferred. The ball milling conditions include: the rotation speed of the grinding ball can be 300-500r/min, the temperature in the ball milling tank can be 15-100 ℃, and the ball milling time can be 0.1-100 hours.
In the present invention, the specific operation method and conditions of the spray drying are preferably: adding a slurry prepared from the solid powder and water into an atomizer, and rotating at a high speed to realize spray drying. Wherein the spray drying conditions may include: the temperature can be 100-300 ℃, and the rotating speed can be 10000-15000 r/min; preferably, the spray drying conditions include: the temperature is 150-250 ℃, and the rotating speed is 11000-13000 r/min; most preferably, the spray drying conditions include: the temperature is 200 ℃, and the rotating speed is 12000 r/min.
According to the invention, the method for removing the template agent is preferably a calcination method. The conditions for removing the template agent may include: the temperature is 300-600 ℃, preferably 350-550 ℃, and most preferably 500 ℃; the time is 10 to 80 hours, preferably 20 to 30 hours, most preferably 24 hours.
According to the invention, in the step (d), the metal component loaded on the spherical tri-mesoporous composite material carrier can adopt an impregnation mode, the metal component enters the pore channel of the spherical tri-mesoporous composite material carrier by virtue of capillary pressure of the pore channel structure of the carrier, and meanwhile, the metal component can be adsorbed on the surface of the spherical tri-mesoporous composite material carrier until the metal component reaches adsorption balance on the surface of the carrier. The dipping treatment may be a co-dipping treatment or a stepwise dipping treatment. In order to save the preparation cost and simplify the experimental process, the dipping treatment is preferably co-dipping treatment; further preferably, the conditions of the co-impregnation treatment include: the spherical tri-mesoporous composite material carrier is mixed and contacted with a solution containing a Pt component precursor and a Zn component precursor, the dipping temperature can be 25-50 ℃, and the dipping time can be 2-6 h.
According to the invention, the Pt component precursor is preferably H2PtCl6The Zn component precursor is preferably Zn (NO)3)2。
The concentration of the solution containing the Pt component precursor and the Zn component precursor is not particularly limited in the present invention, and may be conventionally selected in the art, for example, the concentration of the Pt component precursor may be 0.001 to 0.003mol/L, and the concentration of the Zn component precursor may be 0.015 to 0.1 mol/L.
According to the present invention, the solvent removal treatment can be carried out by a method conventional in the art, for example, a rotary evaporator can be used to remove the solvent in the system.
According to the present invention, in the step (d), the drying may be performed in a drying oven, and the firing may be performed in a muffle furnace. The drying conditions may include: the temperature is 110-150 ℃ and the time is 3-6 h; the conditions for the firing may include: the temperature is 600 ℃ and 650 ℃, and the time is 5-8 h.
According to the invention, in the step (d), the spherical tri-mesoporous composite material carrier, the Pt component precursor and the Zn component precursor are used in amounts such that the content of the carrier is 98-99.4 wt%, the content of the Pt component calculated by Pt element is 0.1-0.5 wt% and the content of the Zn component calculated by Zn element is 0.5-1.5 wt% in the prepared isobutane dehydrogenation catalyst based on the total weight of the isobutane dehydrogenation catalyst.
Preferably, the spherical tri-mesoporous composite material carrier, the Pt component precursor and the Zn component precursor are used in amounts such that, in the prepared isobutane dehydrogenation catalyst, based on the total weight of the isobutane dehydrogenation catalyst, the content of the carrier is 98.4 to 99 wt%, the content of the Pt component calculated by the Pt element is 0.2 to 0.4 wt%, and the content of the Zn component calculated by the Zn element is 0.8 to 1.2 wt%.
According to the present invention, the solvent removal treatment can be carried out by a method conventional in the art, for example, a rotary evaporator can be used to remove the solvent in the system.
According to the present invention, in step (c), the drying may be performed in a drying oven, and the drying conditions may include: the temperature is 110-150 ℃ and the time is 3-6 h.
According to the invention, in the step (c), since the filtering and washing step in the process of forming the spherical tri-mesoporous composite material carrier is performed in the ceramic membrane filter, and the content of sodium ions in sodium element in the mixed material after filtering and washing is not higher than 0.2 wt%, and the content of the template agent is not higher than 1 wt%, the requirement of removing the template agent is met, the product obtained after the spherical tri-mesoporous composite material carrier is subjected to the dipping treatment does not need to be subjected to the conventional calcination treatment to remove the template agent.
In a second aspect, the present invention provides an isobutane dehydrogenation catalyst prepared by the aforementioned process.
According to the invention, the isobutane dehydrogenation catalyst comprises a carrier, and a Pt component and a Zn component which are loaded on the carrier, wherein the carrier is a spherical tri-mesoporous composite material carrier, the spherical tri-mesoporous composite material carrier contains a mesoporous molecular sieve material with a one-dimensional hexagonal pore channel distribution structure and a mesoporous molecular sieve material with a two-dimensional hexagonal pore channel distribution structure, the average particle size of the spherical tri-mesoporous composite material carrier is 30-60 mu m, and the specific surface area is 150-600 m-2Per g, pore volume of 0.5-1.5mL/g, pore size distribution of trimodal distributionThe most probable pore diameters corresponding to the three peaks are respectively 5-15nm, 20-40nm and 45-60 nm.
According to the invention, in the isobutane dehydrogenation catalyst, the spherical tri-mesoporous composite material used as the carrier combines the advantages of the mesoporous molecular sieve material with the one-dimensional hexagonal pore distribution structure, the mesoporous molecular sieve material with the two-dimensional hexagonal pore distribution structure and the spherical carrier, breaks through the limitation of a single one-dimensional pore channel on molecular transmission, is beneficial to the good dispersion of metal components in the pore channel, so that the spherical tri-mesoporous composite material carrier is suitable for being used as the carrier of a supported catalyst, the formed supported catalyst has more excellent catalytic performance in a catalytic reaction, and the beneficial effects of high raw material conversion rate and high product selectivity are obtained.
According to the invention, the spherical three-mesoporous composite material carrier has special one-dimensional and two-dimensional hexagonal pore canal three-hole distribution structures, the average particle size of particles is measured by adopting a laser particle size distribution instrument, and the specific surface area, the pore volume and the most probable pore diameter are measured by a nitrogen adsorption method. In the present invention, the particle size refers to the particle size of the raw material particles, and is expressed by the diameter of the sphere when the raw material particles are spherical, by the side length of the cube when the raw material particles are cubic, and by the mesh size of the screen that can sieve out the raw material particles when the raw material particles are irregularly shaped.
According to the invention, the spherical tri-mesoporous composite material carrier can ensure that the spherical tri-mesoporous composite material carrier is not easy to agglomerate by controlling the particle size of the spherical tri-mesoporous composite material carrier within the range, and the conversion rate of reaction raw materials in the reaction process of preparing isobutene by isobutane dehydrogenation can be improved by using the supported catalyst prepared by using the spherical tri-mesoporous composite material carrier as the carrier. When the specific surface area of the spherical tri-mesoporous composite material carrier is less than 150m2When the volume/g and/or pore volume is less than 0.5mL/g, the catalytic activity of the supported catalyst prepared by using the supported catalyst is remarkably reduced; when the specific surface area of the spherical tri-mesoporous composite material carrier is more than 600m2(ii) when/g and/or the pore volume is greater than 1.5mL/g, supported catalysis made using the same as a supportThe agent is easy to agglomerate in the reaction process of preparing isobutene by isobutane dehydrogenation, so that the conversion rate of reaction raw materials in the reaction process of preparing isobutene by isobutane dehydrogenation is influenced.
Preferably, the average particle diameter of the spherical mesoporous composite material carrier is 35-55 μm, and the specific surface area is 180-600m2The pore volume is 0.8-1.2mL/g, the pore size distribution is trimodal, and the most probable pore sizes corresponding to the trimodal are 6-14nm, 22-38nm and 46-58nm, respectively.
According to the invention, based on the total weight of the isobutane dehydrogenation catalyst, the content of the carrier is 98-99.4 wt%, the content of the Pt component calculated by Pt element is 0.1-0.5 wt%, and the content of the Zn component calculated by Zn element is 0.5-1.5 wt%.
Preferably, the content of the carrier is 98.4-99 wt%, the content of the Pt component calculated by Pt element is 0.2-0.4 wt%, and the content of the Zn component calculated by Zn element is 0.8-1.2 wt%, based on the total weight of the isobutane dehydrogenation catalyst.
Further preferably, the average particle diameter of the isobutane dehydrogenation catalyst is 30-60 μm, and the specific surface area is 180-350m2The pore volume is 0.6-1.2mL/g, the pore size distribution is trimodal, and the most probable pore sizes corresponding to the trimodal are 6-12nm, 25-35nm and 46-55nm, respectively.
According to the present invention, in the spherical tri-mesoporous composite carrier, with respect to 100 parts by weight of the total amount of the mesoporous molecular sieve material having a one-dimensional hexagonal pore distribution structure and the mesoporous molecular sieve material having a two-dimensional hexagonal pore distribution structure; the weight ratio of the content of the mesoporous molecular sieve material with the one-dimensional hexagonal pore channel distribution structure to the content of the mesoporous molecular sieve material with the two-dimensional hexagonal pore channel distribution structure can be 1: (0.1-10), preferably 1: (0.5-2).
According to the present invention, the spherical tri-mesoporous composite support may further contain silica introduced through silica gel. The term "silica introduced through silica gel" refers to a silica component which is brought into the finally prepared spherical tri-mesoporous composite material carrier by using silica gel as a preparation raw material during the preparation process of the spherical tri-mesoporous composite material carrier. In the spherical tri-mesoporous composite carrier, the content of the silica introduced through the silica gel may be 1 to 200 parts by weight, preferably 50 to 150 parts by weight, with respect to 100 parts by weight of the total amount of the mesoporous molecular sieve material having a one-dimensional hexagonal pore distribution structure and the mesoporous molecular sieve material having a two-dimensional hexagonal pore distribution structure.
According to the present invention, the mesoporous molecular sieve material having a one-dimensional hexagonal pore distribution structure and the mesoporous molecular sieve material having a two-dimensional hexagonal pore distribution structure may each be a mesoporous molecular sieve material conventionally used in the art, and may be prepared according to a conventional method.
As described above, the third aspect of the present invention provides a use of the isobutane dehydrogenation catalyst prepared by the foregoing method in preparing isobutene through isobutane dehydrogenation, wherein the method for preparing isobutene through isobutane dehydrogenation comprises: isobutane was subjected to a dehydrogenation reaction in the presence of a catalyst and hydrogen.
When the isobutane dehydrogenation catalyst prepared by the method provided by the invention is used for catalyzing isobutane to dehydrogenate to prepare isobutene, the conversion rate of isobutane and the selectivity of isobutene can be greatly improved.
According to the present invention, in order to increase the isobutane conversion rate and prevent the catalyst from coking, it is preferable that the molar ratio of the amount of isobutane to the amount of hydrogen is (0.5-1.5): 1.
the conditions for the dehydrogenation reaction in the present invention are not particularly limited and may be conventionally selected in the art, and for example, the conditions for the dehydrogenation reaction may include: the reaction temperature is 550-650 ℃, the reaction pressure is 0.05-0.2MPa, the reaction time is 20-40h, and the mass space velocity of isobutane is 2-5h-1。
The present invention will be described in detail below by way of examples.
In the following examples and comparative examples, the triblock copolymer polyoxyethylene-polyoxypropylene-polyoxyethylene, available from Aldrich, is abbreviated as P123 and has the formula EO20PO70EO20In the United states of AmericaThe Abstract has a registry number 9003-11-6 and an average molecular weight Mn of 5800.
In the following examples and comparative examples, filtration washing was performed in an alumina ceramic membrane filter available from kyoto corporation, south of Jiangsu; x-ray diffraction analysis was performed on an X-ray diffractometer model D8 Advance, available from Bruker AXS, Germany; scanning electron microscopy analysis was performed on a scanning electron microscope, model XL-30, available from FEI, USA; pore structure parameter analysis was performed on an ASAP2020-M + C type adsorber, available from Micromeritics, USA, and BET method was used for the specific surface area and pore volume calculation of the sample; the particle size distribution of the sample is carried out on a Malvern laser particle sizer; the rotary evaporator is produced by German IKA company, and the model is RV10 digital; the active component loading of the isobutane dehydrogenation catalyst was measured on a wavelength dispersive X-ray fluorescence spectrometer, available from parnacco, netherlands, model No. Axios-Advanced; analysis of the reaction product composition was performed on a gas chromatograph available from Agilent under model 7890A; the drying box is produced by Shanghai-Hengchun scientific instruments Co., Ltd, and is of a type DHG-9030A; the muffle furnace is manufactured by CARBOLITE corporation, and is of a model CWF 1100; the ultrasonic generator is a KQ-300GTDV high-frequency constant-temperature numerical control ultrasonic cleaner produced by ultrasonic instruments Limited in Kunshan, the ultrasonic frequency is 80kHz, and the working voltage is 220V.
The nitrogen adsorption and desorption experiments of the samples were carried out on a fully automatic physicochemical adsorption analyzer model ASAP2020M + C manufactured by Micromeritics, USA. The samples were degassed at 350 ℃ for 4 hours under vacuum prior to assay. The BET method is adopted to calculate the specific surface area of the sample, and the BJH model is adopted to calculate the pore volume and the average pore diameter.
The NH3-TPD experiment of the sample was carried out on an AUTOCHEM2920 full-automatic chemisorption instrument, manufactured by Micromeritics, USA. The sample was first reduced at 480 ℃ in an atmosphere of 10% H2-90% Ar for 1 hour. Then heating to 700 ℃ in He atmosphere, staying for 1 hour, cooling to 40 ℃ and adsorbing ammonia gas until saturation. After purging for 1h in He gas atmosphere, the temperature was raised from 40 ℃ to 700 ℃ at a rate of 10 ℃/min, while the ammonia desorption data was recorded using a TCD detector.
The content of each metal component in the prepared dehydrogenation catalyst is determined by calculating the raw material feeding during preparation.
The isobutane conversion was calculated as follows:
isobutane conversion rate ═ amount of isobutane consumed by reaction/initial amount of isobutane × 100%;
the isobutene selectivity was calculated as follows:
isobutene selectivity is the amount of isobutane consumed for the production of isobutene/total consumption of isobutane × 100%;
the isobutene yield was calculated as follows:
the isobutene yield is isobutane conversion × isobutene selectivity × 100%.
Example 1
This example is illustrative of an isobutane dehydrogenation catalyst and a method for preparing the same.
(1) Preparation of the support
Adding 1g (0.0002mol) of triblock copolymer surfactant P123 and 1.69g (0.037mol) of ethanol into 28ml of acetic acid and sodium acetate buffer solution with the pH value of 4, stirring at 15 ℃ until the P123 is completely dissolved, then adding 6g (0.053mol) of trimethylpentane into the obtained solution, stirring at 15 ℃ for 8h, then adding 2.13g (0.014mol) of tetramethoxysilane into the solution, stirring at 15 ℃ and the pH value of 4.5 for 20h, then transferring the obtained solution into a reaction kettle with a polytetrafluoroethylene lining, crystallizing at 60 ℃ for 24h, then filtering and washing with deionized water for 4 times, and then carrying out suction filtration to obtain a No. 1 mesoporous molecular sieve material filter cake A1 with a one-dimensional hexagonal pore single-pore distribution structure;
1g (0.003mol) of cetyltrimethylammonium bromide was added to a certain amount of redistilled water, and stirred sufficiently to obtain a homogeneous solution, and the pH of the solution was adjusted to 0.2 with 10mL of a hydrochloric acid aqueous solution having a pH of 0.4. After heating the above solution to 15 ℃, ethyl orthosilicate (TEOS) was slowly added dropwise, wherein, hexadecyltrimethylammonium bromide: ethyl orthosilicate: the molar ratio of the secondary distilled water is 1: 1: 90. then stirring at 15 deg.C for 25 hr, transferring the solution into a kettle with polytetrafluoroethylene lining, and standing at 80 deg.C for hydrothermal crystallization for 40 hr. Then filtering and washing 4 times with deionized water, and then filtering to obtain a No. 2 mesoporous molecular sieve material filter cake A2 with a two-dimensional hexagonal pore path single-pore distribution structure.
Mixing 15 wt% water glass and 12 wt% sulfuric acid solution in a weight ratio of 5:1, reacting at 30 deg.c for 2 hr, regulating the pH to 3 with 98 wt% sulfuric acid, suction filtering the obtained reaction material, and washing with distilled water to sodium ion content of 0.02 wt% to obtain silica gel filter cake B1.
Stirring and mixing 5g of the prepared filter cake A1, 5g of the prepared filter cake A2 and 10g of the prepared filter cake B1, introducing the mixture into a ceramic membrane filtering system, filtering and washing the mixture by using deionized water and ethanol until the content of sodium ions in the mixture is 0.02 weight percent and the content of P123 is 0.5 weight percent in terms of sodium element, collecting the mixture in a ceramic membrane tube, and putting the mixture into a 100ml ball milling tank, wherein the ball milling tank is made of polytetrafluoroethylene, the grinding balls are made of agate, the diameter of the grinding balls is 3mm, the number of the grinding balls is 1, and the rotating speed is 400 r/min. Sealing the ball milling tank, and carrying out ball milling for 1 hour in the ball milling tank at the temperature of 60 ℃ to obtain 30g of solid powder; dissolving the solid powder in 30g of deionized water, and spray-drying at 200 ℃ at a rotating speed of 12000 r/min; calcining the spray-dried product in a muffle furnace at 500 ℃ for 24 hours, and removing the template agent to obtain 30g of a spherical three-mesoporous composite material carrier C1 with a one-dimensional hexagonal pore passage and a two-dimensional hexagonal pore passage three-hole distribution structure. In the preparation process of the spherical tri-mesoporous composite material carrier C1, one ton of the spherical tri-mesoporous composite material carrier C1 is obtained, and three tons of water and ethanol are consumed for filtering and washing by using the ceramic membrane filtering system.
(2) Preparation of isobutane dehydrogenation catalyst
Calcining 30g of the spherical tri-mesoporous composite material C1 obtained in the step (1) at 400 ℃ for 10h under the protection of nitrogen, and carrying out thermal activation treatment to remove hydroxyl and residual moisture of the spherical tri-mesoporous composite material C1.
0.080g H2PtCl6·6H2O and 0.457g Zn (NO)3)2·6H2Dissolving O in 100ml deionized water to obtain a mixtureAnd (2) soaking 10g of the spherical mesoporous composite material C1 prepared in the step (1) in the mixture solution at 25 ℃ for 5h, evaporating solvent water in the system by using a rotary evaporator to obtain a solid product, and drying the solid product in a drying oven at 120 ℃ for 3 h. And then roasting the mixture in a muffle furnace at the temperature of 600 ℃ for 6 hours to obtain the isobutane dehydrogenation catalyst Cat-1 (based on the total weight of the isobutane dehydrogenation catalyst Cat-1, the content of a Pt component in terms of Pt is 0.3 wt%, the content of a Zn component in terms of Zn is 1 wt%, and the balance is a carrier).
The spherical tri-mesoporous composite material carrier C1 and the isobutane dehydrogenation catalyst Cat-1 are characterized by an XRD, a scanning electron microscope and an ASAP2020-M + C type adsorption instrument.
Fig. 1 is an X-ray diffraction pattern, wherein a is an XRD pattern of the spherical tri-mesoporous composite carrier C1, the abscissa is 2 θ, and the ordinate is intensity, and the XRD pattern a of the spherical tri-mesoporous composite carrier C1 has a 2D hexagonal channel structure unique to mesoporous materials, as can be seen from a small-angle spectral peak appearing in the XRD pattern;
FIG. 2 is an SEM (scanning electron microscope) image, which shows that the microscopic morphology of the spherical mesoporous composite material carrier C1 is mesoporous spheres with the granularity of 30-60 μm;
fig. 3 is a pore size distribution graph of the spherical tri-mesoporous composite carrier C1, and it can be seen from the graph that the pore size distribution of the spherical tri-mesoporous composite carrier C1 is a trimodal distribution, and the most probable pore sizes corresponding to the trimodal distributions are 7nm, 30nm and 50nm, respectively.
Table 1 shows the pore structure parameters of the spherical tri-mesoporous composite material carrier C1 and the isobutane dehydrogenation catalyst Cat-1.
TABLE 1
Sample (I) Specific surface area (m)2/g) Pore volume (ml/g) Most probable aperture*(nm) Particle size (. mu.m)
Vector C1 260 1.4 7，30，50 30-60
Catalyst Cat-1 210 1.2 6.5，28，45 30-60
*: the first most probable aperture, the second most probable aperture, and the third most probable aperture are separated by commas: the first most probable aperture, the second most probable aperture and the third most probable aperture are arranged in the order from left to right.
As can be seen from the data of table 1, the specific surface area and the pore volume of the spherical tri-mesoporous composite support are reduced after the Pt component and the Zn component are loaded, which indicates that the Pt component and the Zn component enter the interior of the spherical tri-mesoporous composite support during the loading reaction.
Comparative example 1
This comparative example serves to illustrate a reference isobutane dehydrogenation catalyst and a process for its preparation.
The carrier and the isobutane dehydrogenation catalyst were prepared according to the method of example 1, except that the same weight of alumina carrier was used instead of the spherical tri-mesoporous composite material C1 in the process of preparing the carrier, thereby preparing the carrier D1 and the isobutane dehydrogenation catalyst Cat-D-1, respectively.
Comparative example 2
A support and an isobutane dehydrogenation catalyst were prepared according to the method of example 1, except that commercially available ES955 silica gel (GRACE company) was used as the support D2 instead of the spherical tri-mesoporous composite material C1 in the preparation of the support, thereby preparing a support D2 and an isobutane dehydrogenation catalyst Cat-D-2, respectively.
Comparative example 3
A carrier and an isobutane dehydrogenation catalyst were prepared according to the method of example 1, except that Zn (NO) was not added during the impregnation process for preparing the isobutane dehydrogenation type catalyst3)2·6H2O, addition of only 0.080g H2PtCl6·6H2And O, only loading a single Pt component on the spherical tri-mesoporous composite material serving as the carrier by a co-impregnation method, thereby preparing the isobutane dehydrogenation catalyst Cat-D-3, wherein the content of the Pt component is 0.3 wt% calculated by Pt element and the balance is the carrier on the basis of the total weight of the isobutane dehydrogenation catalyst Cat-D-3).
Example 2
This example is illustrative of an isobutane dehydrogenation catalyst and a method for preparing the same.
(1) Preparation of the support
Adding 1g (0.0002mol) of triblock copolymer surfactant P123 and 1.84g (0.04mol) of ethanol into 28ml of acetic acid and sodium acetate buffer solution with the pH value of 5, stirring at 15 ℃ until the P123 is completely dissolved, then adding 9.12g (0.08mol) of trimethylpentane into the obtained solution, stirring at 15 ℃ for 8 hours, then adding 3.04g (0.02mol) of tetramethoxysilane into the solution, stirring at 25 ℃ and the pH value of 5.5 for 15 hours, then transferring the obtained solution into a reaction kettle with a polytetrafluoroethylene lining, crystallizing at 100 ℃ for 10 hours, then filtering and washing with deionized water for 4 times, and then carrying out suction filtration to obtain a No. 1 mesoporous molecular sieve material filter cake A3 with a one-dimensional hexagonal pore single-pore distribution structure;
1g (0.003mol) of cetyltrimethylammonium bromide was added to a certain amount of redistilled water, and stirred sufficiently to obtain a homogeneous solution, and the pH of the solution was adjusted to 0.1 with 7mL of a hydrochloric acid aqueous solution having a pH of 0.3. After heating the above solution to 30 ℃, ethyl orthosilicate (TEOS) was slowly added dropwise, wherein, hexadecyltrimethylammonium bromide: ethyl orthosilicate: the molar ratio of the secondary distilled water is 1: 1.5: 130. then stirring for 40h at 30 ℃, transferring the solution into a kettle with a polytetrafluoroethylene lining, and standing at 100 ℃ for hydrothermal crystallization treatment for 20 h. Then filtering and washing 4 times with deionized water, and then filtering to obtain a No. 2 mesoporous molecular sieve material filter cake A4 with a two-dimensional hexagonal pore path single-pore distribution structure.
Mixing 15 wt% water glass and 12 wt% sulfuric acid solution in a weight ratio of 4:1, reacting at 40 deg.c for 1.5 hr, regulating the pH value to 2 with 98 wt% sulfuric acid, suction filtering the obtained reaction material, and washing with distilled water to sodium ion content of 0.02 wt% to obtain silica gel filter cake B2.
Stirring and mixing 13g of the prepared filter cake A3, 7g of the prepared filter cake A4 and 10g of the prepared filter cake B2, introducing the mixture into a ceramic membrane filtering system, filtering and washing the mixture by using deionized water and ethanol until the content of sodium ions in the mixture is 0.02 weight percent and the content of P123 is 0.3 weight percent in terms of sodium element, collecting the mixture in a ceramic membrane tube, and putting the mixture into a 100ml ball milling tank, wherein the ball milling tank is made of polytetrafluoroethylene, the grinding balls are made of agate, the diameter of the grinding balls is 3mm, the number of the grinding balls is 1, and the rotating speed is 300 r/min. Sealing the ball milling tank, and carrying out ball milling for 0.5 hour in the ball milling tank at the temperature of 80 ℃ to obtain 38g of solid powder; dissolving the solid powder in 12g of deionized water, and spray-drying at 250 ℃ at the rotating speed of 11000 r/min; calcining the spray-dried product in a muffle furnace at 500 ℃ for 15 hours, and removing the template agent to obtain 35g of spherical tri-mesoporous composite material carrier C2 with a one-dimensional hexagonal pore passage and a two-dimensional hexagonal pore passage three-hole distribution structure. In the preparation process of the spherical tri-mesoporous composite material carrier C2, one ton of the spherical tri-mesoporous composite material carrier C2 is obtained, and four tons of water and ethanol are consumed for filtering and washing by using the ceramic membrane filtering system.
(2) Preparation of isobutane dehydrogenation catalyst
Mixing 0.080g H2PtCl6·6H2O and 0.457g Zn (NO)3)2·6H2Dissolving O in 100ml of deionized water to obtain a mixture solution, soaking 10g of the spherical mesoporous composite material carrier C2 prepared in the step (1) in the mixture solution for 5 hours at 25 ℃, evaporating solvent water in the system by using a rotary evaporator to obtain a solid product, and placing the solid product in a drying oven at 120 ℃ for drying for 3 hours. And then roasting the mixture in a muffle furnace at the temperature of 600 ℃ for 6 hours to obtain the isobutane dehydrogenation catalyst Cat-2 (based on the total weight of the isobutane dehydrogenation catalyst Cat-2, the content of a Pt component in terms of Pt is 0.3 wt%, the content of a Zn component in terms of Zn is 1 wt%, and the balance is a carrier).
Table 2 shows the pore structure parameters of the spherical tri-mesoporous composite material carrier C2 and the isobutane dehydrogenation catalyst Cat-2.
TABLE 2
Sample (I) Specific surface area (m)2/g) Pore volume (ml/g) Most probable aperture*(nm) Particle size (. mu.m)
Vector C2 365 1.3 6.5，28.5，48 30-45
Catalyst Cat-2 328 1.2 6，27，44 30-45
*: the first most probable aperture, the second most probable aperture, and the third most probable aperture are separated by commas: the first most probable aperture, the second most probable aperture and the third most probable aperture are arranged in the order from left to right.
As can be seen from the data of table 2, the specific surface area and the pore volume of the spherical tri-mesoporous composite support are reduced after the Pt component and the Zn component are loaded, which indicates that the Pt component and the Zn component enter the interior of the spherical tri-mesoporous composite support during the loading reaction.
Example 3
This example is illustrative of an isobutane dehydrogenation catalyst and a method for preparing the same.
(1) Preparation of spherical three-mesoporous composite material carrier
Adding 1g (0.0002mol) of triblock copolymer surfactant P123 and 2.76g (0.06mol) of ethanol into 28ml of acetic acid and sodium acetate buffer solution with the pH value of 3, stirring at 15 ℃ until the P123 is completely dissolved, then adding 5.7g (0.05mol) of trimethylpentane into the obtained solution, stirring at 15 ℃ for 8h, then adding 2.13g (0.014mol) of tetramethoxysilane into the solution, stirring at 40 ℃ and the pH value of 3.5 for 10h, then transferring the obtained solution into a reaction kettle with a polytetrafluoroethylene lining, crystallizing at 40 ℃ for 40h, then filtering and washing with deionized water for 4 times, and then carrying out suction filtration to obtain a No. 1 mesoporous molecular sieve material filter cake A5 with a one-dimensional hexagonal pore single-pore distribution structure;
1g (0.003mol) of cetyltrimethylammonium bromide was added to a certain amount of redistilled water, and stirred sufficiently to obtain a homogeneous solution, and the pH of the solution was adjusted to 0.1 with 5mL of a hydrochloric acid aqueous solution having a pH of 0.5. After heating the above solution to 50 ℃, ethyl orthosilicate (TEOS) was slowly added dropwise, wherein, hexadecyltrimethylammonium bromide: ethyl orthosilicate: the molar ratio of the secondary distilled water is 1: 2: 110. then stirring at 50 deg.C for 30h, transferring the solution into a kettle with polytetrafluoroethylene lining, and standing at 140 deg.C for hydrothermal crystallization for 30 h. Then filtering and washing 4 times with deionized water, and then filtering to obtain a No. 2 mesoporous molecular sieve material filter cake A6 with a two-dimensional hexagonal pore path single-pore distribution structure.
Mixing 15 wt% water glass and 12 wt% sulfuric acid solution in the weight ratio of 6:1, contacting and reacting at 20 deg.c for 3 hr, regulating the pH value to 4 with 98 wt% sulfuric acid, suction filtering the obtained reaction material, and washing with distilled water to sodium ion content of 0.02 wt% to obtain silica gel filter cake B3.
Stirring and mixing 7g of the prepared filter cake A5, 13g of the prepared filter cake A6 and 30g of the prepared filter cake B3, introducing the mixture into a ceramic membrane filtering system, filtering and washing the mixture by using deionized water and ethanol until the content of sodium ions in the mixture is 0.02 weight percent and the content of P123 is 0.4 weight percent in terms of sodium element, collecting the mixture in a ceramic membrane tube, and putting the mixture into a 100ml ball milling tank, wherein the ball milling tank is made of polytetrafluoroethylene, the grinding balls are made of agate, the diameter of the grinding balls is 3mm, the number of the grinding balls is 1, and the rotating speed is 550 r/min. Sealing the ball milling tank, and carrying out ball milling for 10 hours in the ball milling tank at the temperature of 40 ℃ to obtain 55g of solid powder; dissolving the solid powder in 30g of deionized water, and spray-drying at 150 ℃ at the rotating speed of 13000 r/min; calcining the spray-dried product in a muffle furnace at 450 ℃ for 70 hours, and removing the template agent to obtain 53g of spherical tri-mesoporous composite material carrier C3 with a one-dimensional hexagonal pore passage and a two-dimensional hexagonal pore passage three-hole distribution structure. In the preparation process of the spherical tri-mesoporous composite material carrier C3, one ton of the spherical tri-mesoporous composite material carrier C3 is obtained, and three tons of water and ethanol are consumed for filtering and washing by using the ceramic membrane filtering system.
(2) Preparation of isobutane dehydrogenation catalyst
0.080g H2PtCl6·6H2O and 0.457g Zn (NO)3)2·6H2O is dissolved inAnd (2) 100ml of deionized water to obtain a mixture solution, soaking 10g of the spherical mesoporous composite material carrier C3 prepared in the step (1) in the mixture solution at 25 ℃ for 5h, evaporating solvent water in the system by using a rotary evaporator to obtain a solid product, and drying the solid product in a drying oven at 120 ℃ for 3 h. And then roasting the mixture for 6 hours in a muffle furnace at the temperature of 600 ℃ to obtain the isobutane dehydrogenation catalyst Cat-3 (based on the total weight of the isobutane dehydrogenation catalyst Cat-3, the content of a Pt component in terms of Pt is 0.3 wt%, the content of a Zn component in terms of Zn is 1 wt%, and the balance is a carrier).
Table 3 shows the pore structure parameters of the spherical tri-mesoporous composite material carrier C3 and the isobutane dehydrogenation catalyst Cat-3.
TABLE 3
Sample (I) Specific surface area (m)2/g) Pore volume (ml/g) Most probable aperture*(nm) Particle size (. mu.m)
Vector C3 355 1.1 6，27，47.5 30-50
Catalyst Cat-3 330 1 5.8，26，43.5 30-50
*: the first most probable aperture, the second most probable aperture, and the third most probable aperture are separated by commas: the first most probable aperture, the second most probable aperture and the third most probable aperture are arranged in the order from left to right.
As can be seen from the data of table 3, the specific surface area and the pore volume of the spherical tri-mesoporous composite support are reduced after the Pt component and the Zn component are loaded, which indicates that the Pt component and the Zn component enter the interior of the spherical tri-mesoporous composite support during the loading reaction.
Experimental example 1
This example is intended to illustrate the preparation of isobutene using the isobutane dehydrogenation catalyst of the present invention
0.5g of isobutane dehydrogenation catalyst Cat-1 was loaded into a fixed bed quartz reactor, the reaction temperature was controlled at 590 ℃, the reaction pressure was 0.1MPa, and the isobutane: the molar ratio of hydrogen is 1: 1, the reaction time is 24 hours, and the mass space velocity of the isobutane is 4 hours-1. By Al2O3The reaction product separated by the S molecular sieve column was directly fed into an Agilent 7890A gas chromatograph equipped with a hydrogen flame detector (FID) for on-line analysis, and the isobutane conversion and isobutene selectivity were obtained as shown in Table 4. After the reaction, the amount of carbon deposition in the isobutane dehydrogenation catalyst Cat-1 was measured using a TGA/DSC1 thermogravimetric analyzer from METTLER-TOLEDO, as shown in table 4.
Experimental examples 2 to 3
Isobutene was prepared by dehydrogenation of isobutane according to the method of experimental example 1, except that isobutane dehydrogenation catalyst Cat-2 and isobutane dehydrogenation catalyst Cat-3 were used instead of isobutane dehydrogenation catalyst Cat-1, respectively. The isobutane conversion, isobutene selectivity and carbon deposition amount of the isobutane dehydrogenation catalyst are shown in table 4.
Experimental comparative examples 1 to 4
Isobutene is prepared by isobutane dehydrogenation according to the method of the experimental example 1, except that isobutane dehydrogenation catalysts Cat-D-1 to Cat-D-3 are respectively adopted to replace the isobutane dehydrogenation catalyst Cat-1. The isobutane conversion, isobutene selectivity and carbon deposition amount of the isobutane dehydrogenation catalyst are shown in table 4.
TABLE 4
Dehydrogenation catalyst Isobutane conversion rate Selectivity to isobutene Carbon deposition amount of catalyst
Experimental example 1 Cat-1 43％ 92％ 1.3wt％
Experimental example 2 Cat-2 42％ 91％ 1.2wt％
Experimental example 3 Cat-3 41％ 90％ 1.5wt％
Experimental comparative example 1 Cat-D-1 12.5％ 71.3％ 5.3wt％
Experimental comparative example 2 Cat-D-2 17.2％ 20.5％ 6.2wt％
Experimental comparative example 3 Cat-D-3 24.5％ 55.6％ 3.1wt％
It can be seen from table 4 that when the isobutane dehydrogenation catalyst prepared by using the spherical tri-mesoporous composite material carrier of the present invention is used for preparing isobutene through isobutane dehydrogenation, after 24 hours of reaction, high isobutane conversion rate and isobutene selectivity can be obtained, which indicates that the isobutane dehydrogenation catalyst of the present invention has not only good catalytic performance, but also good stability and low carbon deposition.
The preferred embodiments of the present invention have been described above in detail, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the scope of the invention.

Claims (11)

1. A method for preparing an isobutane dehydrogenation catalyst, characterized in that the method comprises the following steps:
(a) under the existence of a first template agent, trimethylpentane and ethanol, tetramethoxysilane is contacted with a first acid agent, and a product obtained after the contact is crystallized and filtered to obtain a No. 1 mesoporous material filter cake; in the presence of a second template agent, contacting tetraethoxysilane with a second acid agent, and crystallizing and filtering a mixture obtained after the contact to obtain a No. 2 mesoporous material filter cake;
(b) contacting water glass with inorganic acid, and filtering a product obtained after the contact to obtain a silica gel filter cake;
(c) mixing the No. 1 mesoporous material filter cake, the No. 2 mesoporous material filter cake and the silica gel filter cake, then sequentially filtering, washing and ball-milling the mixed material, pulping solid powder obtained after ball-milling with water, then performing spray drying, and removing the template agent from the obtained product to obtain a spherical tri-mesoporous composite material carrier;
(d) dipping the spherical tri-mesoporous composite material carrier obtained in the step (c) in a solution containing a Pt component precursor and a Zn component precursor, and then sequentially carrying out solvent removal treatment, drying and roasting;
wherein, the filtration washing in the step (c) is carried out in a ceramic membrane filter, and the content of sodium ions in the mixed material after filtration washing is not higher than 0.2 percent by weight and the content of the template agent is not higher than 1 percent by weight calculated by sodium element.
2. The method of claim 1, wherein in step (a), the molar ratio of the first template, ethanol, trimethylpentane, and tetramethoxysilane is 1: (100-500): (200-600): (50-200); the molar ratio of the second template agent to the tetraethoxysilane is 1: (1-2.5);
preferably, the first template agent is triblock copolymer polyoxyethylene-polyoxypropylene-polyoxyethylene, the second template agent is cetyl trimethyl ammonium bromide, the first acid agent is a buffer solution of acetic acid and sodium acetate with the pH value of 1-6, and the second acid agent is hydrochloric acid with the pH value of 0-1;
further preferably, the conditions under which the tetramethoxysilane is contacted with the first acid agent include: the temperature is 10-60 ℃, the time is 10-72 hours, and the pH value is 1-7; the condition of contacting the ethyl orthosilicate with the second acid agent comprises the following steps: the temperature is 10-60 ℃, the time is 10-72 hours, and the pH value is 0-1; the crystallization conditions include: the temperature is 30-150 ℃ and the time is 10-72 hours.
3. The method of claim 1, wherein in step (b), the conditions under which the water glass is contacted with the mineral acid comprise: the temperature is 10-60 ℃, the time is 1-5 hours, and the pH value is 2-4; the inorganic acid is one or more of sulfuric acid, nitric acid and hydrochloric acid.
4. The method according to claim 1, wherein in step (c), the silica gel filter cake is used in an amount of 1 to 200 parts by weight, preferably 50 to 150 parts by weight, based on 100 parts by weight of the total amount of the filter cake of mesoporous material No. 1 and the filter cake of mesoporous material No. 2, and the weight ratio of the filter cake of mesoporous material No. 1 to the filter cake of mesoporous material No. 2 is 1: (0.1-10), preferably 1 (0.5-2).
5. The method according to claim 1, wherein in the step (d), the spherical tri-mesoporous composite support, the Pt component precursor and the Zn component precursor are used in amounts such that the support is contained in an amount of 98-99.4 wt%, the Pt component is contained in an amount of 0.1-0.5 wt% in terms of Pt element, and the Zn component is contained in an amount of 0.5-1.5 wt% in terms of Zn element, based on the total weight of the isobutane dehydrogenation catalyst, in the prepared isobutane dehydrogenation catalyst.
6. An isobutane dehydrogenation catalyst produced by the process of any one of claims 1-5.
7. An isobutane dehydrogenation catalyst according to claim 6, wherein the isobutane dehydrogenation catalyst comprises a support and a Pt group supported on the supportAnd Zn component, wherein the carrier is a spherical tri-mesoporous composite material carrier, the spherical tri-mesoporous composite material carrier contains a mesoporous molecular sieve material with a one-dimensional hexagonal pore channel distribution structure and a mesoporous molecular sieve material with a two-dimensional hexagonal pore channel distribution structure, the average particle diameter of the spherical tri-mesoporous composite material carrier is 30-60 mu m, and the specific surface area is 150-600 m-2The pore volume is 0.5-1.5mL/g, the pore size distribution is trimodal, and the most probable pore sizes corresponding to the trimodal are 5-15nm, 20-40nm and 45-60nm respectively.
8. An isobutane dehydrogenation catalyst according to claim 7, wherein the carrier is present in an amount of 98-99.4 wt%, the Pt component is present in an amount of 0.1-0.5 wt% calculated as Pt element, and the Zn component is present in an amount of 0.5-1.5 wt% calculated as Zn element, based on the total weight of the isobutane dehydrogenation catalyst;
preferably, the average particle diameter of the isobutane dehydrogenation catalyst is 30-60 mu m, and the specific surface area is 180-350m2The pore volume is 0.6-1.2mL/g, the pore size distribution is trimodal, and the most probable pore sizes corresponding to the trimodal are 6-12nm, 25-35nm and 46-55nm, respectively.
9. The isobutane dehydrogenation catalyst according to claim 7, wherein the weight ratio of the mesoporous molecular sieve material having a one-dimensional hexagonal pore distribution structure to the mesoporous molecular sieve material having a two-dimensional hexagonal pore distribution structure is 1: (0.1-10), preferably 1 (0.5-2).
10. Use of the isobutane dehydrogenation catalyst according to any one of claims 6 to 9 in the production of isobutene by the dehydrogenation of isobutane, wherein the method for producing isobutene by the dehydrogenation of isobutane comprises: isobutane was subjected to a dehydrogenation reaction in the presence of a catalyst and hydrogen.
11. The process according to claim 10, wherein the molar ratio of the amount of isobutane to the amount of hydrogen is (0.5-1.5): 1;
preferably, the dehydrogenation reaction conditions include: the reaction temperature is 550-650 ℃, the reaction pressure is 0.05-0.2MPa, the reaction time is 20-40h, and the mass space velocity of isobutane is 2-5h-1。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115608410A (en) * 2021-07-13 2023-01-17 中国石油化工股份有限公司 Catalyst for synthesizing n-butyl acetate and preparation method and application thereof

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015161701A1 (en) * 2014-04-22 2015-10-29 武汉凯迪工程技术研究总院有限公司 Cobalt-based fischer-tropsch synthesis catalyst coated with mesoporous materials and preparation method therefor
CN105435852A (en) * 2014-06-09 2016-03-30 中国石油化工股份有限公司 Mesoporous composite material and catalyst and preparation method and application thereof and 2,2-dimethyl-4-methyl-1,3-dioxolane preparation method
CN105618026A (en) * 2016-01-05 2016-06-01 中国石油大学(华东) Catalyst for catalytic dehydrogenation of alkane as well as preparation method and application method of catalyst
CN106311311A (en) * 2015-06-19 2017-01-11 中国石油化工股份有限公司 Catalyst for preparing propylene through propane dehydrogenation, preparation method of catalyst, and method for propylene through propane dehydrogenation
CN106607099A (en) * 2015-10-22 2017-05-03 中国石油化工股份有限公司 Catalyst for preparing low-carbon olefin by dehydrogenizing low-carbon alkane and preparation method of catalyst
CN107456992A (en) * 2016-06-06 2017-12-12 中国石油化工股份有限公司 Spherical zeolite mesoporous composite material and loaded catalyst and its preparation method and application and acid isopropyl preparation method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015161701A1 (en) * 2014-04-22 2015-10-29 武汉凯迪工程技术研究总院有限公司 Cobalt-based fischer-tropsch synthesis catalyst coated with mesoporous materials and preparation method therefor
CN105435852A (en) * 2014-06-09 2016-03-30 中国石油化工股份有限公司 Mesoporous composite material and catalyst and preparation method and application thereof and 2,2-dimethyl-4-methyl-1,3-dioxolane preparation method
CN106311311A (en) * 2015-06-19 2017-01-11 中国石油化工股份有限公司 Catalyst for preparing propylene through propane dehydrogenation, preparation method of catalyst, and method for propylene through propane dehydrogenation
CN106607099A (en) * 2015-10-22 2017-05-03 中国石油化工股份有限公司 Catalyst for preparing low-carbon olefin by dehydrogenizing low-carbon alkane and preparation method of catalyst
CN105618026A (en) * 2016-01-05 2016-06-01 中国石油大学(华东) Catalyst for catalytic dehydrogenation of alkane as well as preparation method and application method of catalyst
CN107456992A (en) * 2016-06-06 2017-12-12 中国石油化工股份有限公司 Spherical zeolite mesoporous composite material and loaded catalyst and its preparation method and application and acid isopropyl preparation method

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
J. SILVESTRE-ALBERO ET AL.: "Zn-modified MCM-41 as support for Pt catalysts", 《APPLIED CATALYSIS A: GENERAL》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115608410A (en) * 2021-07-13 2023-01-17 中国石油化工股份有限公司 Catalyst for synthesizing n-butyl acetate and preparation method and application thereof
CN115608410B (en) * 2021-07-13 2023-10-13 中国石油化工股份有限公司 Catalyst for synthesizing n-butyl acetate and preparation method and application thereof

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Application publication date: 20191227