CN112742397A

CN112742397A - Synthetic alcohol catalyst and preparation method and application thereof

Info

Publication number: CN112742397A
Application number: CN201911053364.5A
Authority: CN
Inventors: 侯朝鹏; 孙霞; 张荣俊; 徐润; 夏国富; 阎振楠
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2019-10-31
Filing date: 2019-10-31
Publication date: 2021-05-04
Anticipated expiration: 2039-10-31
Also published as: CN112742397B

Abstract

The invention provides a synthetic alcohol catalyst and a preparation method and application thereof, wherein the synthetic alcohol catalyst comprises a carrier and an active metal component loaded on the carrier, wherein the active metal component is Cu or Cu-Co, the carrier is raspberry-type oxide microspheres, the raspberry-type oxide microspheres are hollow microspheres with a large pore on the surface, a hollow structure is arranged inside the hollow microspheres, the large pore is communicated with the hollow structure to form a cavity with an opening at one end, and oxides in the raspberry-type oxide microspheres are selected from one or more of aluminum oxide and silicon oxide. Because the diffusion distance is short and the macroscopic surface area is large, the CO conversion rate and the alcohol selectivity of the alcohol synthesizing catalyst are obviously higher than those of a solid catalyst, and the alcohol synthesizing catalyst has better alcohol synthesizing performance.

Description

Synthetic alcohol catalyst and preparation method and application thereof

Technical Field

The invention relates to the field of catalysts, and particularly relates to a synthetic alcohol catalyst, and a preparation method and application thereof.

Background

In the past decades, a great deal of literature has been studying and reporting inorganic hollow microsphere materials. Compared with a common dense sphere, the hollow material has smaller density and larger specific surface area, is widely applied to various fields such as drug catalyst carriers, gas adsorbents and the like, and in recent years, the research and application of the inorganic hollow microsphere material are receiving more and more attention.

The alumina composition cavity ball is a new-type high-temp. heat-insulating material made up by using industrial alumina through the processes of smelting and blowing in electric furnace, and its crystal form is a-Al₂O₃A microcrystal. The alumina hollow ball is used as main body, and can be made into various shaped products, and the product has high mechanical strength which is several times that of general light products, but the volume density is far less than that of solid products. The energy-saving furnace is widely applied to high-temperature and ultra-high-temperature furnaces such as petrochemical industry gasification furnaces, carbon black industry reaction furnaces, metallurgical industry induction furnaces and the like, and obtains a very satisfactory energy-saving effect. The existing preparation methods of alumina cavity materials include a high-temperature melting and spray reaction method, a template method, a layer-by-layer self-assembly method (L-b-L) and a microemulsion method.

The silica hollow microsphere has the advantages of good biocompatibility, easily available raw materials, low price and the like, and is widely applied to the fields of drug carriers, biological signal markers, coatings and the like, and the preparation technology of the inorganic hollow microsphere is also widely concerned by researchers. The most widely reported method is to use polystyrene microspheres as a template, wrap a silicon oxide shell layer on the surface of the polystyrene microspheres, and remove a polystyrene core to obtain the silicon oxide hollow microspheres. The preparation methods reported in the literature at present mainly comprise (1) an electrostatic adsorption method; (2) silicon cross-linking agent modification; (3) Layer-by-Layer (Layer-by-Layer) method.

The hollow spherical zirconia powder is a plasma spraying heat-insulating material for surface modification of mechanical parts such as aircraft engines, gas turbines, heat treatment equipment and the like, and a coating prepared from the powder has the characteristics of good thermal shock resistance and high-temperature hot corrosion resistance, so that the hollow spherical zirconia powder is sprayed on high-temperature parts such as aircraft engines and the like, the mechanical property of the engines can be improved, and the service life of the high-temperature parts can be prolonged. The hollow porous zirconia microspheres have stable chemical properties, can be used as a micro controlled release carrier (such as a drug sustained release agent) of active substances, do not react with loaded drug active ingredients, have good biocompatibility, do not pollute the environment, and can effectively control the nanometer pore canal of the particle size and the pore diameter. The prior methods for producing the hollow zirconia comprise a plasma spheroidization method and a spray drying granulation method. The plasma spheroidizing method is a process method for preparing hollow sphere powder by using a plasma spray gun as a heat source and carrying out heat treatment on porous zirconia agglomerated powder prepared by other methods.

The titanium dioxide hollow microsphere structure can enlarge the specific surface area of titanium dioxide, can provide more active sites for catalytic reaction, and the higher crystallinity of the titanium dioxide hollow microsphere structure can reduce the recombination rate of photo-generated electrons and active holes, thereby improving the catalytic activity. On the other hand, from the modification perspective, the hollow structure may provide space for further modification of the titanium dioxide material. At present, there are various methods for synthesizing hollow titanium oxide, such as template method, flame combustion method and template-free method, among which, the template method is easy to control the aperture and shell thickness of the microsphere, and the dispersion is relatively uniform. However, the template method has complex steps, and the shell layer is easily damaged in the process of removing the template; the flame combustion method and the template-free method have the advantages of continuous preparation process, simple operation, no pollution and the like, but the prepared product is irregular.

Methanol is used as an important basic chemical raw material and clean fuel and is widely applied to the fields of organic synthesis, medicines, pesticides, dyes, coatings, plastics, synthetic rubber, synthetic fibers, automobiles, national defense and the like. The low-carbon mixed alcohol can be used as an excellent clean vehicle fuel, and has the advantages of sufficient combustion, high efficiency, low emission of CO, NOx and hydrocarbons and the like because the alcohol contains oxygen. It is a good clean fuel, and the research of low carbon alcohol is also concerned by the increasing market demand of higher alcohols with higher economic price in recent years. Therefore, the reaction for synthesizing the methanol and the low-carbon mixed alcohol by CO hydrogenation catalysis has important application prospect in the chemical field.

At present, the industrial scale production of methanol and low carbon mixed alcohol usually takes synthesis gas as raw material, and the synthesis gas is obtained by reaction under the conditions of certain temperature, pressure and existence of catalyst. With the rapid development of social economy, the demand and production capacity of methanol and low-carbon mixed alcohol are continuously increased at home and abroad, so that the research of the high-performance synthetic alcohol catalyst is promoted to become a research hotspot for the production of the methanol and the low-carbon mixed alcohol.

It is noted that the information disclosed in the foregoing background section is only for enhancement of background understanding of the invention and therefore it may contain information that does not constitute prior art that is already known to a person of ordinary skill in the art.

Disclosure of Invention

The invention aims to provide a synthetic alcohol catalyst with high CO conversion rate and high alcohol selectivity aiming at the defects of the prior art.

In order to achieve the purpose, the invention adopts the following technical scheme:

a synthetic alcohol catalyst comprises a carrier and an active metal component loaded on the carrier, wherein the active metal component is Cu or Cu-Co, the carrier is a raspberry type oxide microsphere, the raspberry type oxide microsphere is a hollow microsphere with a large pore on the surface, a hollow structure is arranged inside the hollow microsphere, the large pore and the hollow structure are communicated to form a cavity with one open end, and an oxide in the raspberry type oxide microsphere is selected from one or more of aluminum oxide, silicon oxide, zirconium oxide and titanium oxide, preferably one or more of aluminum oxide and silicon oxide.

In some embodiments, the support is present in an amount of 30 to 98 wt% and the active metal component is present in an amount of 2 to 70 wt%, calculated as oxide and based on the catalyst.

In some embodiments, the diameter of the hollow structure is 1-2000 μm, preferably 1-400 μm, and the shell thickness of the hollow microsphere is 0.2-1000 μm, preferably 0.5-200 μm.

In some embodiments, the macropores have a pore size of 0.2 to 1000 μm, preferably 0.5 to 200 μm.

In some embodiments, the raspberry type oxide microspheres have a particle size of 3 to 2500 μm, preferably 10 to 500 μm, and a sphericity of 0.50 to 0.99.

In some embodiments, the raspberry-type oxide microspheres have a fragmentation rate of 0 to 1%.

In some embodiments, the alcohol synthesis catalyst further comprises an adjunct component selected from one or more of La, Zr, Ce, W, Mn, Ti, V, Cr, Fe, Co, Zn, Sc, Mg, Ca, Be, Na, K, Ru, Ag, Au, Re, Pt and Pd, in an amount of from 0.001 to 25 wt%, preferably from 0.01 to 10 wt%, calculated as element and based on the catalyst

In another aspect, the present invention provides a method for preparing the above synthetic alcohol catalyst, comprising the steps of:

providing a dipping solution of raspberry type oxide microspheres and a compound containing the active metal component;

roasting the raspberry type oxide microspheres to obtain the carrier; and

and (3) impregnating the carrier by using the impregnating solution, and drying, roasting and activating to obtain the synthetic alcohol catalyst.

In some embodiments, the step of providing raspberry-type oxide microspheres comprises:

adding nitrate, peptizing agent, pore-forming agent, oxide and/or precursor thereof into a dispersing agent and stirring to obtain dispersed slurry;

aging the dispersed slurry;

sending the aged dispersed slurry into a drying device, wherein the air inlet temperature is 400-1200 ℃, and preferably 450-700 ℃; and drying and forming under the condition that the air outlet temperature is 50-300 ℃, preferably 120-200 ℃ to obtain the raspberry type oxide microspheres.

In some embodiments, the nitrate is selected from one or more of aluminum nitrate, zirconium nitrate, lanthanum nitrate, and yttrium nitrate.

In some embodiments, the peptizing agent is selected from one or more of acids, bases, and salts.

In some embodiments, the pore former is selected from one or more of starch, synthetic cellulose, polymeric alcohols, and surfactants.

In some embodiments, the oxide and/or its precursor is selected from one or more of an aluminum source selected from one or more of pseudo-boehmite, aluminum alkoxide, aluminum nitrate, aluminum sulfate, aluminum chloride, and sodium metaaluminate, a silicon source selected from one or more of silicate, sodium silicate, water glass, and silica sol, a zirconium source selected from one or more of zirconium dioxide, zirconium tetrachloride, zirconium oxychloride, zirconium hydroxide, zirconium sulfate, zirconium phosphate, zirconyl nitrate, zirconium hydroxycarbonate, and zirconium tetrabutoxide, and a titanium source selected from one or more of titanium dioxide, metatitanic acid, titanium nitrate, titanyl sulfate, titanium dichloride, titanium trichloride, titanium tetrachloride, titanium aluminum titanium chloride, tetraethyl titanate, tetrabutyl titanate, tetra-n-propyl titanate, and tetra-isopropyl titanate.

In some embodiments, the dispersant is selected from one or more of water, alcohols, ketones, and acids.

In some embodiments, the mass ratio of the nitrate, the peptizing agent, the pore former, and the oxide and/or a precursor thereof is (10-500): (1-10): (10-500): (10-1000).

In some embodiments, the method further comprises adding a blasting agent to the dispersing agent, wherein the blasting agent is selected from one or more of picric acid, trinitrotoluene, digested glycerol, nitrocotton, danner explosive, hexogen, and C4 plastic explosive, and the addition amount of the blasting agent is 0-1% of the total dry basis weight of the nitrate, the peptizing agent, the pore-forming agent, and the oxide and/or a precursor thereof.

In some embodiments, the drying device is a flash drying device or a spray drying device.

In some embodiments, the temperature of the aging treatment is 0 to 90 ℃.

In some embodiments, the roasting temperature is 400-1300 ℃, preferably 450-1100 ℃, more preferably 500-700 ℃, the drying temperature is 80-200 ℃, preferably 100-150 ℃, and the roasting activation temperature is 200-800 ℃, preferably 300-600 ℃.

In another aspect, the invention provides an application of the above synthetic alcohol catalyst in preparation of methanol and/or low-carbon mixed alcohol from synthesis gas.

Because the diffusion distance is short and the macroscopic surface area is large, the CO conversion rate and the alcohol selectivity of the cavity alcohol synthesis catalyst are obviously higher than those of a solid catalyst, and the cavity alcohol synthesis catalyst has better alcohol synthesis performance. .

Drawings

FIGS. 1 to 4 are SEM photographs of raspberry type microspherical catalysts prepared in examples 1 to 4.

FIG. 5 is an SEM photograph of a microspherical catalyst prepared in comparative example 1.

FIG. 6 is an SEM photograph of a microspherical catalyst prepared in comparative example 2.

Detailed Description

The technical solution of the present invention is further explained below according to specific embodiments. The scope of protection of the invention is not limited to the following examples, which are set forth for illustrative purposes only and are not intended to limit the invention in any way.

In the present invention, anything or matters not mentioned is directly applicable to those known in the art without any change except those explicitly described. Moreover, any embodiment described herein may be freely combined with one or more other embodiments described herein, and the technical solutions or ideas thus formed are considered part of the original disclosure or original description of the present invention, and should not be considered as new matters not disclosed or contemplated herein, unless a person skilled in the art would consider such combination to be clearly unreasonable.

All features disclosed in this invention may be combined in any combination and such combinations are understood to be disclosed or described herein unless a person skilled in the art would consider such combinations to be clearly unreasonable. 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.

According to a first aspect of the present invention, there is provided a synthetic alcohol catalyst comprising a support and an active metal component supported on the support.

In the synthetic alcohol catalyst of the present invention, the active metal component is Cu or Cu — Co (mixture of Cu and Co), and when the target product is methanol, the preferred active metal component is Cu; when the target product is a low-carbon mixed alcohol, the preferable active metal components are Cu and Co, wherein the molar ratio of Cu to Co is 0.05-50: 1, preferably the molar ratio is 0.1-20: 1.

in the synthetic alcohol catalyst, the carrier is raspberry-type oxide microspheres which are hollow microspheres similar to raspberry-type structures, the surface of each hollow microsphere is provided with a large hole, each hollow microsphere is internally provided with a hollow structure, and the large holes and the hollow structures are communicated to form a cavity with one open end.

The oxide in the raspberry type oxide microspheres is an inorganic oxide, and can be selected from one or more of alumina, silica, zirconia and titania, and preferably from one or more of alumina, silica and titania.

The particle size of the raspberry type oxide microspheres is 3-500 mu m, preferably 10-500 mu m, the diameter of the hollow structure is 1-2000 mu m, preferably 1-400 mu m, and the pore diameter of the surface macropores is 0.2-1000 mu m, preferably 0.5-200 mu m. The raspberry type oxide microsphere has a shell layer surrounding a cavity, and the thickness of the raspberry type oxide microsphere is 0.2-1000 microns, preferably 0.5-200 microns.

The appearance of the raspberry type oxide microspheres is close to spherical, and the sphericity of the raspberry type oxide microspheres is 0.50-0.99.

Sphericity of microbead blank

σ＝4πA/L²

And (6) calculating. In the formula: sigma is sphericity; a is the projected area of the microsphere in m²(ii) a L is the projection perimeter of the microsphere, and the unit is m; a and L are obtained from SEM pictures of microspheres and processed by Image processing software Image-Pro Plus.

The raspberry type oxide microspheres are roasted at 400-1300 ℃, preferably 450-1100 ℃, and more preferably 500-700 ℃ to obtain oxides, and the specific surface area of the oxides is about 0.1-900 m²A preferred range is 10 to 300m²A pore volume of about 0.01 to 3.6ml/g, preferably 0.1 to 0.9 ml/g.

The breakage rate of the raspberry type oxide microspheres is 0-1%, the breakage rate is measured according to a method provided by a similar strength standard number Q/SH 3360226-2010, and the specific method is as follows:

firstly, selecting sieves S1 and S2 with meshes of M1 and M2 respectively, wherein M1 is less than M2, enabling microspheres to be detected to firstly pass through a sieve S1 with meshes of M1, then enabling the sieved microsphere powder to pass through a sieve S2 with meshes of M2, and finally enabling the microsphere powder intercepted by the sieve S2 to serve as a sample to be detected.

Adding a sample to be tested with a certain mass into a cylindrical steel container with the section diameter of 10mm, applying a certain pressure to microspheres through a cylinder for a certain time, screening the pressed microsphere powder through a screen S2 with the mesh number of M2, recording the mass of the microsphere powder under the screen, and dividing the mass of the microsphere powder under the screen by the total mass of the added microspheres to obtain the breaking rate of the microspheres.

In the present invention, M1 can be 100 mesh, M2 can be 150 mesh, pressure can be 100N, and time can be 10 s.

The strength of the microspheres can be evaluated by using the breakage rate; the lower the breakage rate, the higher the strength of the microspheres

The raspberry type oxide microspheres of the invention have low breaking rate and strength significantly higher than the existing known oxide microspheres, such as the apple-shaped hollow molecular sieve microspheres disclosed in CN108404970A, under the condition of pressurization, which is determined by the difference of the raw materials and the preparation method. The higher strength enables the porosity of the raspberry type oxide microspheres to be larger, the pressure drop to be greatly reduced, meanwhile, the raspberry type oxide microspheres have excellent processing performance and loss resistance, the reaction diffusion distance in the field of catalysts prepared by using the raspberry type oxide microspheres as carriers is short, the raspberry type oxide microspheres have wide application prospects, and the raspberry type oxide microspheres can also be prepared into high-temperature heat-insulating materials, biological materials and photochemical materials.

In the alcohol synthesis catalyst, the content of the active metal component is 2-70 wt%, preferably 5-50 wt%, more preferably 10-30 wt%, and the content of the carrier is 30-98 wt%, preferably 50-95 wt%, more preferably 70-90 wt%, calculated on the oxide and based on the catalyst.

The synthetic alcohol catalyst of the present invention may also contain any substance that improves catalyst performance. For example, one or more auxiliary components selected from La, Zr, Ce, W, Mn, Ti, V, Cr, Fe, Co, Zn, Sc, Mg, Ca, Be, Na or K may Be introduced, or one or more auxiliary components selected from Ru, Ag, Au, Re, Pt and Pd may Be introduced, and the amount of the above-mentioned auxiliary components introduced is 0.001 to 25 wt%, preferably 0.01 to 10 wt%, in terms of elements and based on the catalyst.

The synthetic alcohol catalyst can be applied to the production of methanol and/or low-carbon mixed alcohol by using synthesis gas.

The synthetic alcohol catalyst of the invention can be prepared by the following method, comprising the following steps:

providing an impregnation solution of raspberry-type oxide microspheres and a compound containing an active metal component;

roasting the raspberry type oxide microspheres to obtain a carrier; and

impregnating the carrier by using an impregnating solution, and drying, roasting and activating to obtain the synthetic alcohol catalyst.

In the preparation method, the raspberry type oxide microspheres can be prepared by the following method:

adding nitrate, peptizing agent, pore-forming agent, aluminum source and/or silicon source into the dispersing agent and stirring to obtain dispersed slurry;

aging the dispersed slurry; and

sending the aged dispersion slurry into a drying device, wherein the air inlet temperature is 400-1200 ℃, and preferably 450-700 ℃; and drying and forming under the condition that the air outlet temperature is 50-300 ℃ and preferably 120-200 ℃ to obtain the raspberry type oxide microspheres.

In the preparation method of the invention, the nitrate is selected from one or more of aluminum nitrate, zirconium nitrate, lanthanum nitrate and yttrium nitrate. Nitrate ions in the nitrate promote a self-propagating combustion reaction at high temperatures that can act as an oxidizer for the pore former, producing gases and vapors that form cavities in the oxide material.

In the preparation method of the invention, the peptizing agent is selected from one or more of acids, alkalis and salts. The acids can be selected from: inorganic acid (such as hydrochloric acid, sulfuric acid, nitric acid and the like), organic acid (formic acid, acetic acid, oxalic acid and the like) and one or more of inorganic acid or organic acid; alkalies can be selected from: inorganic bases (sodium hydroxide, potassium hydroxide, barium hydroxide, calcium hydroxide, aluminum hydroxide, lithium hydroxide, magnesium hydroxide, zinc hydroxide, copper hydroxide, iron hydroxide, lead hydroxide, cobalt hydroxide, chromium hydroxide, zirconium hydroxide, nickel hydroxide, ammonium hydroxide, soda ash (anhydrous sodium carbonate), sodium carbonate (monohydrate, heptahydrate, decahydrate), sodium bicarbonate (baking soda), potassium carbonate, potassium bicarbonate, etc.), organic bases (such as amine compounds, alkali metal salts of alcohols, alkaloids, lithium alkyl metal compounds, etc.), and one or more of inorganic acids or organic acids; the salts can be selected from: inorganic acid salt (such as hydrochloric acid, sulfate, nitrate, etc.), organic acid salt (formate, acetate, oxalate, etc.), and one or more of inorganic acid salt or organic acid salt.

In the preparation method of the invention, the pore-forming agent is selected from one or more of starch, synthetic cellulose, polymeric alcohol and surfactant. Wherein the synthetic cellulose is preferably one or more of carboxymethyl cellulose, methyl cellulose, ethyl cellulose and hydroxy fiber fatty alcohol polyvinyl ether; the polymer alcohol is preferably one or more of polyethylene glycol, polypropylene alcohol, polyvinyl alcohol and polypropylene alcohol PPG; the surfactant is preferably one or more of fatty alcohol polyvinyl ether, fatty alcohol amide and derivatives thereof, acrylic acid copolymer with molecular weight of 200-2000000 and maleic acid copolymer.

In the preparation method of the invention, the oxide and/or the precursor thereof can be directly alumina, silica, zirconia and titania, or the precursor forming the oxide can be used, and specifically can be one or more selected from an aluminum source, a silicon source, a zirconium source and a titanium source, wherein the aluminum source is one or more selected from pseudo-boehmite, aluminum alkoxide, aluminum nitrate, aluminum sulfate, aluminum chloride and sodium metaaluminate, the silicon source is one or more selected from silicate, sodium silicate, water glass and silica sol, the zirconium source is one or more selected from zirconium dioxide, zirconium tetrachloride, zirconium oxychloride, zirconium hydroxide, zirconium sulfate, zirconium phosphate, zirconium oxynitrate, zirconium nitrate, zirconium hydroxycarbonate and tetrabutoxy zirconium, the titanium source is one or more selected from titanium dioxide, metatitanic acid, titanium nitrate, titanyl sulfate, titanium dichloride, titanium trichloride, titanium tetrachloride, titanium aluminum titanium chloride and tetraethyltitanate, one or more of tetrabutyl titanate, tetra-n-propyl titanate, and tetra-isopropyl titanate.

When the above aluminum source, silicon source, zirconium source and titanium source are used, they may further include a chemical agent for precipitating or gelling them, such as acids (e.g., inorganic acids such as hydrochloric acid, sulfuric acid and nitric acid, or organic acids such as acetic acid), and/or alkalis (e.g., sodium carbonate and sodium hydroxide).

When it is necessary to prepare an oxide composition containing other components, oxides such as vanadium oxide, chromium oxide, manganese oxide, molybdenum oxide, tungsten oxide, iron oxide, cobalt oxide, nickel oxide, and copper oxide may be added, and precursors that can form these oxides may also be added.

In the preparation method, the dispersing agent is selected from one or more of water, alcohols, ketones and acids, wherein the alcohols can be methanol, ethanol, propanol and the like, the ketones can be acetone, butanone and the acids can be formic acid, acetic acid, propionic acid and the like. The preferable dispersing agent is a mixture of water and a small amount of ethanol, the small amount of ethanol can play a better dispersing effect in water and can be used as a boiling point regulator, and the water evaporation effect and the liquid drop shrinkage effect are matched and matched more through regulating the dispersing agent, so that the appearance effect of the microsphere is more regular and smooth.

In the preparation method, the mass ratio of the nitrate, the peptizing agent, the pore-forming agent and the oxide and/or the precursor thereof is (10-500): (1-10): (10-500): (10-1000).

In the preparation method, the nitrate, the peptizing agent, the pore-forming agent and the oxide and/or the precursor thereof can be sequentially added into the dispersing agent or simultaneously added, the adding sequence can be adjusted according to the dissolution condition of the raw materials, and the raw materials are stirred to be uniformly mixed while being added.

The preparation method of the invention can also comprise adding a blasting agent into the dispersing agent, wherein the blasting agent can be added before or after the oxide. The blasting agent is selected from one or more of picric acid, trinitrotoluene, digested glycerol, nitrocotton, dana explosive, hexogen and C4 plastic explosive. Before drying and forming, the blasting agent is mixed with other materials uniformly. The addition amount of the blasting agent is 0-1% of the total dry basis weight of the nitrate, the peptizing agent, the pore-forming agent and the oxide and/or the precursor thereof.

In the preparation method, the nitrate, the peptizing agent, the pore-forming agent and the precursor of the oxide are sequentially added into the dispersing agent for pulping, and the slurry is pumped into a sand mill or a colloid mill for grinding after being uniformly stirred to obtain the dispersed slurry. The solid content of the slurry is generally 5-60 wt% during pulping, and the grinding time is 1-30 minutes. After mixing and grinding, the average particle size of the aluminum, silicon, zirconium and titanium source particles in the slurry may be ground to 0.01-10 μm.

After the raw materials are mixed and ground, the raw materials are fully dissolved and dispersed, so that the dispersed slurry is uniform. The milling equipment used may be a colloid mill, sand mill or other equipment, the criterion being selected such that the catalyst fines, after grinding thereof, reach the desired average particle size, i.e. less than 10 μm.

And then aging the dispersed slurry at 0-90 ℃ for 0.1-24 hours, preferably 0.5-2 hours.

And (3) after aging treatment, feeding the dispersed slurry into a drying device, drying and forming at the air inlet temperature of 400-1200 ℃, preferably 450-700 ℃, the air outlet temperature of 50-300 ℃, preferably 120-200 ℃, and the pressure in a spray tower is similar to that of conventional spraying, so that the raspberry type oxide microspheres can be obtained.

The drying apparatus used in the present invention may be a flash drying apparatus and a spray drying apparatus, preferably a spray drying apparatus. Flash drying and spray drying are common methods applied for material drying. After the wet material is dispersed in a drying tower, the moisture is quickly vaporized in the contact with hot air, and a dry product is obtained. The spray drying method can directly dry the solution and emulsion into powder or granular products, and can omit the procedures of evaporation, pulverization and the like.

The working principle of spray drying is to disperse the material to be dried into fine mist-like particles by mechanical action (such as pressure, centrifugation, air-flow type spraying), increase the evaporation area of water, accelerate the drying process, contact with hot air, remove most of the water in a short time, and dry the solid matter in the material into powder.

The spray drying apparatus used in the present invention is a conventional apparatus in the existing flow path, and the present invention is not particularly limited thereto. The spray drying apparatus generally comprises: the device comprises a feeding system, a hot air system, a drying tower system, a receiving system and a sealing system. The feeding system is connected with the drying tower system in the middle of the top end, the hot air system is connected with the side face of the top end of the drying tower system, the receiving system is connected with the bottom end of the drying tower system, and the sealing system is connected with the hot air system. In the spray drying process, it is essentially necessary to have a spray of the stock solution; drying the tiny droplets in the spray; three functions of separating and recovering fine powder products. In the spray drying apparatus, an atomizer, a drying chamber, and a fine powder recoverer corresponding to the above functions are generally equipped.

Because the control parameters in the spray drying process are more and the factors are complex, the particle size and the particle shape after spray drying are very complex. The size range of the product is generally in micron order, and the product is generally a mixture of shapes including a sphere, a disc, an apple shape, a grape shape, a cavity shape, a meniscus shape and the like, and how to selectively form an ideal single shape, such as a cavity shape, is a difficulty in the formation of the product.

One method in the prior art is to form spherical emulsion under the action of surface tension of a surfactant, and then at the moment of spray forming at a lower temperature, a pore-forming agent is vaporized or pyrolyzed in the spherical emulsion, and gas generated by vaporization and pyrolysis can cause a cavity in the microsphere emulsion; and (3) slowly releasing gas to form macropores on the surface to be communicated with the internal hollow structure, forming secondary stacking holes on the molecular sieve particles in the spray forming process to form mesopores on the surface of the molecular sieve microspheres, and combining the subsequent roasting process to obtain the large-particle hollow molecular sieve microspheres.

In the method, under the high temperature of the inlet air temperature of 400-1200 ℃, the oxide and the reducing agent in the slurry generate strong oxidation-reduction self-propagating combustion reaction to instantly generate a large amount of gas; meanwhile, the liquid drops enter a high-temperature area for spraying, the liquid drops are strongly evaporated, and the surface tension formed by the thickened slurry causes the liquid drops to shrink rapidly. The strong explosion of the inside and the strong contraction of the outside form a raspberry type hollow material with good strength. The prepared raspberry type oxide microspheres have high strength, high sphericity and high yield.

The raspberry type oxide microspheres can be used as a carrier after being roasted, and can be prepared into various catalysts after being loaded with corresponding active components. The roasting temperature can be 400-1300 ℃, the preferable temperature is 450-1100 ℃, and the preferable temperature is 500-700 ℃; the roasting time can be 1-12 h, preferably 2-8 h, and more preferably 3-4 h.

In the impregnation solution of the compound containing the active metal component, the compound containing the active metal component is selected from one or more soluble compounds thereof, such as one or more soluble complexes of cobalt nitrate, cobalt acetate, cobalt carbonate hydroxide, cobalt chloride and cobalt, and preferably cobalt nitrate and cobalt carbonate hydroxide.

The supporting method of the present invention is preferably an impregnation method comprising preparing an impregnation solution of the compound containing the active metal component, and thereafter impregnating the support with the solution. The impregnation method is a conventional method, and for example, it may be an excess liquid impregnation method, a pore saturation method impregnation method. Wherein the specified content of catalyst can be prepared by adjusting and controlling the concentration, amount or carrier amount of the impregnation solution containing the active metal component, as will be readily understood and realized by those skilled in the art.

The active metal component and the auxiliary component may be co-impregnated or may be separately impregnated, preferably co-impregnated.

The product needs to be dried after impregnation, the drying temperature is 80-200 ℃, preferably 100-150 ℃, the used drying device and the operating conditions thereof are conventional equipment and operating parameters in the prior drying technology, and the invention has no special limitation.

And roasting and activating the dried product to obtain the catalyst, wherein the roasting and activating temperature is 200-800 ℃, and the preferable temperature is 300-600 ℃. The roasting apparatus used and its operating conditions are conventional equipment and operating parameters in the prior art roasting, and the present invention is not particularly limited thereto.

The application of the raspberry type oxide microspheres can reduce the waste of the carrier and the catalyst and save materials; meanwhile, due to the improvement of the shape efficiency factor, the diffusion can be promoted, and the reaction efficiency and the selectivity of a target product are improved. In the reaction with larger heat effect, the hollow carrier can also reduce the generation of hot spots, and has good intrinsic safety.

Because the diffusion distance is short and the macroscopic surface area is large, the CO conversion rate and the alcohol selectivity of the alcohol synthesizing catalyst are obviously higher than those of a solid catalyst, and the alcohol synthesizing catalyst has better alcohol synthesizing performance. In addition, the preparation method of the invention has lower cost and can be applied in large-scale industry.

The present invention will be described in detail with reference to examples, but the scope of the present invention is not limited thereto.

Examples

Reagents, instruments and tests

In the following examples, preparations and comparative examples, some of the raw material specifications used were as follows:

pseudo-boehmite powder (produced by Changling catalyst factory, solid content 69.5 wt%; gamma-Al)₂O₃Content of not less than 98 wt%);

alumina sol (produced by Zhou village catalyst works, containing 22 wt% Al)₂O₃)；

Sodium silicate (Jinan Yifengda chemical limited company, modulus 3.1-3.4, insoluble substance less than 0.4%)

Ammonia, hydrochloric acid, nitric acid, sulfuric acid, aluminum sulfate, aluminum chloride, zirconium hydroxide, zirconium oxychloride, titanium tetrachloride, titanium dioxide (national chemical group, ltd., industrial grade);

polyethylene glycol PEG4000 powder (Wenzhou Shuanghoi rubber and plastic materials Co., Ltd.);

methylcellulose (Hubei Jiangtangtai chemical Co., Ltd.);

tetraethoxysilane (TEOS, jonan hua special chemical limited, content about 99%);

aluminum nitrate, titanium nitrate, zirconium nitrate, yttrium nitrate, magnesium nitrate (Yutai Qixin chemical Co., Ltd., industrial grade)

The breakage of the support and the catalyst can be measured according to the following method:

the microspheres to be measured firstly pass through a 100-mesh sieve, then the sieved microsphere powder passes through a 150-mesh sieve, and finally the microsphere powder intercepted by the 150-mesh sieve is used as a sample to be measured. Adding microspheres with a certain mass (the granularity is 100-150 meshes) into a cylindrical steel container with the section diameter of 10mm, applying a certain pressure (100N) to the microspheres through a cylinder for a certain time (10 seconds), screening the pressed microsphere powder by using a 150-mesh screen, recording the mass of the microsphere powder under the screen, and dividing the mass of the microsphere powder under the screen by the total mass of the added microspheres to obtain the breaking rate of the microspheres.

Preparation example 1

20kg of water is added into a reaction kettle, 0.5kg of zirconium nitrate is added into the reaction kettle, 175g of concentrated nitric acid is added into the reaction kettle, 2kg of PEG4000 and 5g of digestive glycerin are added into the reaction kettle, and finally 4.6kg of pseudo-boehmite powder is added into the reaction kettle, and the mixture is uniformly stirred and ground to obtain dispersed slurry.

The dispersion slurry was aged at 25 ℃ for 0.5 hour with stirring.

Feeding the aged dispersed slurry into a spray drying device for drying and forming to obtain raspberry type oxide microspheres, wherein the atomization pressure of spray drying is 0.3-3.0 MPa, and the pressure in a tower is-0.0010-0.0090 MPa; the initial air inlet temperature of drying is 560 ℃, and the air outlet temperature of drying termination is 140 ℃.

Preparation example 2

40kg of water is added into a reaction kettle, 0.5kg of cerous nitrate is added into the reaction kettle, 200g of concentrated sulfuric acid is added into the reaction kettle, 1kg of PEG4000 and 5g of picric acid are added into the reaction kettle, and 3kg of sodium silicate is added into the reaction kettle, stirred uniformly and ground to obtain dispersion slurry.

The dispersion slurry was aged at 25 ℃ for 1 hour with stirring.

Feeding the aged dispersed slurry into a spray drying device for drying and forming to obtain raspberry type oxide microspheres, wherein the atomization pressure of spray drying is 0.3-3.0 MPa, and the pressure in a tower is-0.0010-0.0090 MPa; the initial air inlet temperature of drying is 600 ℃, and the air outlet temperature of drying termination is 180 ℃.

Preparation example 3

30kg of water is added into a reaction kettle, 0.7kg of zirconium nitrate is added into the reaction kettle, 2L of concentrated ammonia water is added, 1.5kg of PEG4000 and 8g of picric acid are added, and finally 7kg of zirconium hydroxide is added, stirred uniformly and ground to obtain dispersion slurry.

The dispersion slurry was aged at 25 ℃ for 2 hours with stirring.

Preparation example 4

30kg of water is added into a reaction kettle, 0.7kg of titanium nitrate is added into the reaction kettle, then 2.6L of concentrated ammonia water is added, 1.5kg of PEG4000 and 6g of picric acid are added, and finally 500g of concentrated nitric acid and 7kg of titanium nitrate are added, stirred uniformly and ground to obtain dispersed slurry.

The dispersion slurry was aged at 25 ℃ for 2 hours with stirring.

Feeding the aged dispersed slurry into a spray drying device for drying and forming to obtain raspberry type oxide microspheres, wherein the atomization pressure of spray drying is 0.3-3.0 MPa, and the pressure in a tower is-0.0010-0.0090 MPa; the initial air inlet temperature of drying is 560 ℃, and the air outlet temperature of drying termination is 141 ℃.

Example 1

The raspberry type oxide microspheres obtained in preparation example 1 were calcined at 600 ℃ to obtain a carrier ZT1, and the physical properties thereof are shown in table 1.

The carrier ZT1 was dipped in copper nitrate and zinc nitrate solution several times to make a catalyst with Cu content of 40.0% and Zn content of 20.0%, dried at 120 deg.C and calcined at 420 deg.C to obtain CAT1, the physical properties of which are shown in Table 2.

The SEM photograph of the catalyst prepared in example 1 is shown in FIG. 1.

Example 2

The raspberry type oxide microspheres obtained in preparation example 2 were calcined at 500 ℃ to obtain a carrier ZT2, and the physical properties thereof are shown in table 1.

The carrier ZT2 was dipped in copper nitrate and zinc nitrate solution several times to make a catalyst with Cu content of 40.0% and Zn content of 20.0%, dried at 110 deg.C and calcined at 350 deg.C to obtain CAT2, the physical properties of which are shown in Table 2.

The SEM photograph of the catalyst prepared in example 2 is shown in FIG. 2.

Example 3

The raspberry type oxide microspheres obtained in preparation example 3 were calcined at 550 ℃ to obtain a carrier ZT3, and the physical properties thereof are shown in table 1.

The carrier ZT3 was dipped in copper nitrate and cobalt nitrate solution several times to make a catalyst with Cu content of 12.0% and Co content of 6.0%, dried at 120 deg.C and calcined at 420 deg.C to obtain catalyst CAT3, the physical properties of which are shown in Table 2.

The SEM photograph of the catalyst prepared in example 3 is shown in FIG. 3.

Example 4

The raspberry type oxide microspheres obtained in preparation example 4 were calcined at 700 ℃ to obtain a carrier ZT4, and the physical properties thereof are shown in table 1.

The carrier ZT4 was dipped in copper nitrate and cobalt nitrate solution several times to make a catalyst with Cu content of 12.0% and Co content of 6.0%, dried at 130 deg.C, and calcined at 370 deg.C to obtain catalyst CAT4, the physical properties of which are shown in Table 2.

The SEM photograph of the catalyst prepared in example 4 is shown in FIG. 4.

Comparative example 1

Adding 20kg of water into a reaction kettle, adding 4.5kg of pseudo-boehmite powder, and stirring and mixing uniformly; adding 200g of concentrated hydrochloric acid, mixing and grinding; adding 2.3kg of PEG4000, continuing pulping, stirring and aging at 25 ℃ for 1 hour, and drying and forming by using a spray drying device to obtain oxide microspheres, wherein the atomization pressure of spray drying is 0.3-3.0 MPa, and the pressure in the tower is-0.0010-0.0090 MPa; the initial air inlet temperature of drying is 560 ℃, and the air outlet temperature of drying termination is 145 ℃.

The microphotograph of the obtained oxide microspheres is shown in fig. 5, which shows that the oxide microspheres are substantially solid, and a hollow structure communicating with the outside rarely exists in the central part.

The oxide microspheres are roasted at 600 ℃ to obtain a carrier DBZT1, and the physical properties of the carrier are shown in Table 1.

The carrier DBZT1 was dipped in copper nitrate and zinc nitrate solution for several times to make a catalyst with Cu content of 40.0% and Zn content of 20.0%, dried at 120 deg.C and calcined at 420 deg.C to obtain the catalyst DBCAT-Zn-1, the physical properties of which are shown in Table 2.

The carrier DBZT1 was dipped in copper nitrate and cobalt nitrate solution for several times to make a catalyst with Cu content of 12.0% and Co content of 6.0%, dried at 130 deg.C, and calcined at 370 deg.C to obtain the catalyst DBCAT-Co-1, the physical properties of which are shown in Table 2.

Comparative example 2

Adding 30kg of water and 5.5kg of sodium silicate into a reaction kettle, and stirring and mixing uniformly; adding 200g of concentrated hydrochloric acid; the resulting dispersion was filtered and the precipitate was washed 2 times with ethanol and deionized water, respectively, to remove unreacted inorganic and organic impurities.

Adding 20kg of water and 2.0kg of PEG4000, continuing pulping, stirring and aging for 1 hour at 25 ℃, and drying and molding by using a spray drying device to obtain oxide microspheres, wherein the atomization pressure of spray drying is 0.3-3.0 MPa, and the pressure in the tower is-0.0010-0.0090 MPa; the initial air inlet temperature of drying is 450 ℃, and the air outlet temperature of drying termination is 120 ℃.

When observed under a microscope, the structure is also substantially solid as shown in fig. 6, and no hollow structure communicating with the outside exists in the central part.

The oxide microspheres are roasted at 600 ℃ to obtain a carrier DBZT2, and the physical properties of the carrier are shown in Table 1.

The carrier DBZT2 was dipped in copper nitrate and zinc nitrate solution for several times to make a catalyst with Cu content of 40.0% and Zn content of 20.0%, dried at 120 deg.C and calcined at 420 deg.C to obtain the catalyst DBCAT-Zn-2, the physical properties of which are shown in Table 2.

The carrier DBZT2 was dipped in copper nitrate and cobalt nitrate solution for several times to make a catalyst with Cu content of 12.0% and Co content of 6.0%, dried at 120 deg.C and calcined at 420 deg.C to obtain catalyst DBCAT-Co-2, the physical properties of which are shown in Table 2.

TABLE 1 physical Properties of the vectors

TABLE 2 physical Properties of the catalysts

The catalysts of the examples of the present invention and the comparative examples were tested for their performance in the reaction of synthesizing alcohol by the following application examples.

Application example

The catalysts of examples 1-8 and comparative examples 1-2 were evaluated for their performance in the synthesis reaction of methanol and lower mixed alcohols in a fixed bed reactor, in which the Cu-based catalyst was used for methanol synthesis and the Cu-Co-based catalyst was used for lower mixed alcohol synthesis.

The synthetic alcohol catalyst needs to be reduced before use to reduce the catalyst to a metallic state. Catalyst reduction reaction conditions: the pressure is normal pressure, the heating rate is 5 ℃/min, and the air speed of hydrogen is 600h^-1The reduction temperature was 300 ℃ and the reduction time was 5 hours.

After reduction, a reaction performance test is carried out, and specific reaction conditions are as follows:

reaction conditions of Cu-based catalyst: feed gas composition H₂/CO/N₂70%/20%/10% (volume percentage) pressure 5.0MPa, temperature 230 deg.C, synthetic gas (raw gas) space velocity 9600 h-1. At each reaction temperature point, a gas sample was taken for chromatography after 24 hours. The main indicators of the reaction performance are: CO conversion, methanol selectivity and methanol yield. The results of the reaction performance test are shown in table 3.

Reaction conditions of the Cu-Co based catalyst: feed gas composition H₂/CO/N₂60%/30%/10% (volume/volume) pressure 5.0MPa, temperature 275 deg.C, synthetic gas (raw gas) space velocity 4000h^-1. At each reaction temperature point, a gas sample was taken for chromatography after 24 hours. The main indicators of the reaction performance are: CO conversion, methanol selectivity, C2+ alcohol selectivity, and total alcohol yield. The results of the reaction performance test are shown in table 4.

TABLE 3 reaction Performance test results for Cu-based catalysts

TABLE 4 reaction Performance test results for Cu-Co based catalysts

The test results in tables 3 and 4 show that the synthetic alcohol catalyst prepared by using the raspberry-type oxide microspheres provided by the invention as a catalyst carrier has a significantly higher CO conversion rate and alcohol selectivity than the catalyst of the comparative example under the same other conditions, and shows that the synthetic alcohol catalyst has better synthetic alcohol performance.

It should be noted by those skilled in the art that the described embodiments of the present invention are merely exemplary and that various other substitutions, alterations, and modifications may be made within the scope of the present invention. Accordingly, the present invention is not limited to the above-described embodiments, but is only limited by the claims.

Claims

1. The synthetic alcohol catalyst is characterized by comprising a carrier and an active metal component loaded on the carrier, wherein the active metal component is Cu or Cu-Co, the carrier is a raspberry-type oxide microsphere, the raspberry-type oxide microsphere is a hollow microsphere with a large pore on the surface, a hollow structure is arranged inside the hollow microsphere, the large pore and the hollow structure are communicated to form a cavity with an opening at one end, and the oxide in the raspberry-type oxide microsphere is selected from one or more of alumina, silica, zirconia and titanium oxide.

2. The alcohol synthesizing catalyst according to claim 1, wherein the content of the carrier is 30 to 98% by weight and the content of the active metal component is 2 to 70% by weight in terms of an oxide based on the catalyst.

3. The alcohol synthesizing catalyst according to claim 1, wherein the diameter of the hollow structure is 1 to 2000 μm, preferably 1 to 400 μm, and the shell thickness of the hollow microsphere is 0.2 to 1000 μm, preferably 0.5 to 200 μm.

4. The alcohol synthesizing catalyst according to claim 1, wherein the pore size of the macropores is 0.2 to 1000 μm, preferably 0.5 to 200 μm.

5. The alcohol synthesizing catalyst according to claim 1, wherein the raspberry type oxide microsphere has a particle size of 3 to 2500 μm, preferably 10 to 500 μm, and a sphericity of 0.50 to 0.99.

6. The alcohol synthesizing catalyst according to claim 1, wherein the raspberry type oxide microsphere has a breakage rate of 0 to 1%.

7. A synthetic alcohol catalyst according to any one of claims 1 to 6 further comprising an adjunct component selected from one or more of La, Zr, Ce, W, Mn, Ti, V, Cr, Fe, Co, Zn, Sc, Mg, Ca, Be, Na, K, Ru, Ag, Au, Re, Pt and Pd, in an amount of 0.001 to 25 wt.%, preferably 0.01 to 10 wt.%, calculated as element and based on the catalyst.

8. The method for producing a synthetic alcohol catalyst according to any one of claims 1 to 7, characterized by comprising the steps of:

roasting the raspberry type oxide microspheres to obtain the carrier; and

9. The method of claim 8, wherein the step of providing raspberry-type oxide microspheres comprises:

aging the dispersed slurry;

10. The method according to claim 9, wherein the nitrate is selected from one or more of aluminum nitrate, zirconium nitrate, lanthanum nitrate, and yttrium nitrate.

11. The method according to claim 9, wherein the peptizing agent is selected from one or more of acids, bases and salts.

12. The method of claim 9, wherein the pore former is selected from one or more of starch, synthetic cellulose, polymeric alcohol, and a surfactant.

13. The production method according to claim 9, wherein the oxide and/or the precursor thereof is selected from one or more of an aluminum source, a silicon source, a zirconium source and a titanium source, wherein the aluminum source is selected from one or more of pseudo-boehmite, aluminum alkoxide, aluminum nitrate, aluminum sulfate, aluminum chloride and sodium metaaluminate, the silicon source is selected from one or more of silicate ester, sodium silicate, water glass and silica sol, the zirconium source is selected from one or more of zirconium dioxide, zirconium tetrachloride, zirconium oxychloride, zirconium hydroxide, zirconium sulfate, zirconium phosphate, zirconyl nitrate, zirconium basic carbonate and tetrabutoxy zirconium, the titanium source is selected from one or more of titanium dioxide, metatitanic acid, titanium nitrate, titanyl sulfate, titanium dichloride, titanium trichloride, titanium tetrachloride, aluminum titanium chloride, tetraethyl titanate, tetrabutyl titanate, tetra-n-propyl titanate and tetra-isopropyl titanate.

14. The method according to claim 9, wherein the dispersant is one or more selected from the group consisting of water, alcohols, ketones, and acids.

15. The preparation method according to claim 9, characterized in that the mass ratio of the nitrate, the peptizing agent, the pore-forming agent and the oxide and/or precursor thereof is (10-500): (1-10): (10-500): (10-1000).

16. The preparation method according to claim 9, further comprising adding a blasting agent to the dispersing agent, wherein the blasting agent is selected from one or more of picric acid, trinitrotoluene, digested glycerol, nitrocotton, dana explosive, hexogen, and C4 plastic explosives, and the amount of the blasting agent added is 0-1% of the total dry basis weight of the nitrate, the peptizing agent, the pore-forming agent, and the oxide and/or precursor thereof.

17. The method of claim 9, wherein the drying device is a flash drying device or a spray drying device.

18. The method according to claim 9, wherein the temperature of the aging treatment is 0 to 90 ℃.

19. The preparation method according to claim 8, wherein the roasting temperature is 400-1300 ℃, preferably 450-1100 ℃, more preferably 500-700 ℃, the drying temperature is 80-200 ℃, preferably 100-150 ℃, and the roasting activation temperature is 200-800 ℃, preferably 300-600 ℃.

20. Use of the synthol catalyst according to any one of claims 1 to 7 in the preparation of methanol and/or lower mixed alcohols from synthesis gas.