CN112264029B - Ni-based diesel reforming catalyst and preparation method and application thereof - Google Patents

Ni-based diesel reforming catalyst and preparation method and application thereof Download PDF

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CN112264029B
CN112264029B CN202011300975.8A CN202011300975A CN112264029B CN 112264029 B CN112264029 B CN 112264029B CN 202011300975 A CN202011300975 A CN 202011300975A CN 112264029 B CN112264029 B CN 112264029B
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cerium
catalyst
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CN112264029A (en
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王玉军
薛强强
颜彬航
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Tsinghua University
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    • B01J35/40—
    • 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
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/83—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with rare earths or actinides
    • 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
    • B01J37/03—Precipitation; Co-precipitation
    • B01J37/031—Precipitation
    • 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
    • B01J37/082—Decomposition and pyrolysis
    • B01J37/088—Decomposition of a metal salt
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
    • C01B3/02—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen
    • C01B3/32—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air
    • C01B3/34—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents
    • C01B3/38—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents using catalysts
    • C01B3/40—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents using catalysts characterised by the catalyst
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
    • C01B2203/02—Processes for making hydrogen or synthesis gas
    • C01B2203/0205—Processes for making hydrogen or synthesis gas containing a reforming step
    • C01B2203/0227—Processes for making hydrogen or synthesis gas containing a reforming step containing a catalytic reforming step
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
    • C01B2203/10—Catalysts for performing the hydrogen forming reactions
    • C01B2203/1041—Composition of the catalyst
    • C01B2203/1047—Group VIII metal catalysts
    • C01B2203/1052—Nickel or cobalt catalysts
    • C01B2203/1058—Nickel catalysts
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
    • C01B2203/10—Catalysts for performing the hydrogen forming reactions
    • C01B2203/1041—Composition of the catalyst
    • C01B2203/1082—Composition of support materials
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/50—Improvements relating to the production of bulk chemicals
    • Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

Abstract

The invention provides a Ni-based diesel reforming catalyst, a preparation method and application thereof, belonging to the technical field of diesel reforming catalysts. The method adopts the membrane dispersion microreactor to carry out coprecipitation reaction to prepare the Ni-based catalyst, in the membrane dispersion microreactor, the cross-flow shearing of the microfiltration membrane on the dispersed phase is adopted to realize the rapid and uniform mixing of hydroxyl in the dispersed phase and metal ions in the continuous phase, the fluctuation of the pH value of the reaction in a small interval is controlled, and the high-efficiency mixing and mass transfer in the nucleation stage in the coprecipitation reaction process are realized, so that the mass transfer efficiency is effectively improved, the dispersion degree of active metals is obviously improved, the reaction time is shortened (only 10-20 min is needed for synthesizing 1L slurry), the production efficiency is high, the production continuity can be realized, and the method has important market value and popularization value. The results of the examples show that the yield of hydrogen is greatly improved after the Ni-based diesel reforming catalyst prepared by the method is used for steam reforming of diesel.

Description

Ni-based diesel reforming catalyst and preparation method and application thereof
Technical Field
The invention relates to the technical field of diesel reforming catalysts, in particular to a Ni-based diesel reforming catalyst and a preparation method and application thereof.
Background
Diesel oil is a liquid fuel with high volumetric energy density and is very suitable as a raw material of a mobile hydrogen production device. However, with the increasingly stringent emission standards of greenhouse gases, domestic refineries often adopt higher "diesel-to-steam ratios" for transportation fuel production. The hydrogen production by reforming the surplus diesel provides a new idea for the energy supply of a mobile auxiliary power unit (a solid oxide fuel cell and the like).
Industrial reforming of methane with steam using Ni-Al2O3Catalyst, Cu-ZnO-Al is used for reforming methanol2O3A catalyst. The catalysts have good effect in the application of reforming low-carbon hydrocarbon and alcohol. However, for the reforming of high carbon compounds to produce hydrogen, these commercial catalystsThe problems of poor activity, easy coking and the like exist. In order to solve these problems, researchers have used coprecipitation, sol-gel, adsorption-hydrolytic precipitation, etc. instead of impregnation methods to increase the degree of dispersion of the active metal and thus the activity. Among them, the coprecipitation of a batch synthesis catalyst in a stirred tank is more suitable for industrial production, while other methods are mostly limited by yield and cost. In order to solve the problem of serious carbon deposition, a catalyst carrier with strong oxygen storage-release capacity, such as a cerium-zirconium solid solution, a cerium-lanthanum solid solution, etc., can be adopted. Although the coprecipitation method in a stirred tank can reduce the particle size of the catalyst to a certain extent compared with the impregnation method, the dispersion effect of the active metal in the catalyst has not yet achieved an ideal effect.
In order to achieve uniform dispersion of small-particle-size active metals, the OH content of the lye must be increased during the nucleation phase-And the efficiency of micromixing of the active metal ions in the salt solution. The existing stirring method has low mixing and mass transfer efficiency and can not synthesize the catalyst with highly dispersed active metal.
Disclosure of Invention
The invention aims to provide a Ni-based diesel reforming catalyst and a preparation method and application thereof.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides a preparation method of a Ni-based diesel reforming catalyst, which comprises the following steps:
in a membrane dispersion microreactor, taking a mixed salt solution of nickel salt, cerium salt and zirconium salt as a continuous phase to enter a main channel of the membrane dispersion microreactor, taking an ammonia water solution as a dispersed phase to enter a microfiltration membrane of the membrane dispersion microreactor, shearing the solution, mixing the solution with the continuous phase, and carrying out coprecipitation reaction to obtain slurry;
sequentially aging and separating the slurry to obtain a catalyst precursor;
drying, calcining and reducing the catalyst precursor in sequence to obtain the Ni-based diesel reforming catalyst;
in the cerium salt and the zirconium salt, the molar ratio of Ce to Zr is (1-9): 1, and in the nickel salt and the cerium salt, the molar ratio of Ce to Ni is (1-10): 1.
Preferably, the total metal ion concentration of the mixed salt solution of the nickel salt, the cerium salt and the zirconium salt is 0.02-2 mol/L; the concentration of the ammonia water solution is 0.02-2 mol/L.
Preferably, the length of the main channel is 10mm, and the width and the height of the main channel are 0.5-2 mm independently; the aperture of the microfiltration membrane is 2-20 mu m.
Preferably, the flow rate of the continuous phase is 1-20 mL/min, the flow rate of the dispersed phase is 3-100 mL/min, and the phase ratio of the dispersed phase to the continuous phase is 3-5.
Preferably, the membrane dispersion microreactor is placed in a water bath at 0-30 ℃ to perform the coprecipitation reaction.
Preferably, the aging temperature is 0-30 ℃ and the aging time is 1-6 h.
Preferably, the calcination is carried out in an air atmosphere, the calcination temperature is 400-600 ℃, and the calcination time is 2-6 hours; the reduction temperature is 400-600 ℃, and the reduction time is 2-4 h.
The invention provides a Ni-based diesel reforming catalyst prepared by the preparation method in the technical scheme, which comprises a carrier and an active component loaded on the carrier, wherein the active component is nickel, the carrier is a cerium-zirconium solid solution, and the cerium-zirconium solid solution is CexZr1-xO2Wherein x is 0.5-0.9; the active component accounts for 3-25% by mass.
Preferably, x is 0.6-0.8, and the mass percentage of the active component is 5-15%.
The invention provides the application of the Ni-based diesel reforming catalyst in the technical scheme in the preparation of hydrogen by diesel reforming.
The invention provides a preparation method of a Ni-based diesel reforming catalyst, which comprises the following steps: in a membrane dispersion microreactor, taking a mixed salt solution of nickel salt, cerium salt and zirconium salt as a continuous phase to enter a main channel of the membrane dispersion microreactor, taking an ammonia water solution as a dispersed phase to enter a microfiltration membrane of the membrane dispersion microreactor, shearing the solution, mixing the solution with the continuous phase, and carrying out coprecipitation reaction to obtain slurry; sequentially aging and separating the slurry to obtain a catalyst precursor; drying, calcining and reducing the catalyst precursor in sequence to obtain the Ni-based diesel reforming catalyst; in the cerium salt and the zirconium salt, the molar ratio of Ce to Zr is (1-9): 1, and in the nickel salt and the cerium salt, the molar ratio of Ce to Ni is (1-10): 1.
According to the invention, a membrane dispersion microreactor is adopted for carrying out coprecipitation reaction to prepare the Ni-based catalyst, in the membrane dispersion microreactor, the cross-flow shearing of a microfiltration membrane on a dispersion phase is adopted to realize the rapid and uniform mixing of hydroxyl in the dispersion phase and metal ions in a continuous phase, so that the efficient mixing and mass transfer in a nucleation stage in the coprecipitation reaction process are realized, and the fluctuation of the reaction pH value in a small interval is controlled, thereby effectively improving the mass transfer efficiency, obviously improving the dispersion degree of active metals, shortening the reaction time (only 10-20 min is needed for synthesizing 1L slurry), having high production efficiency, being capable of realizing the production continuity and having important market value and popularization value; the particle size of nickel in the prepared Ni-based catalyst is 4-5 nm. The method provided by the invention overcomes the problems that the nickel particle size is large (6.5-8 nm) and the dispersion is uneven in the catalyst prepared by the existing stirring method, so that the catalytic activity is not high; meanwhile, the problems of low mass transfer efficiency, long reaction time (more than 1h is needed for synthesizing 1L of slurry) and low production efficiency of the existing stirring method (dropwise adding ammonia water) mixing are solved. The results of the examples show that the yield of hydrogen is greatly improved after the Ni-based diesel reforming catalyst prepared by the method is used for steam reforming of diesel.
The invention can ensure that Ce and Zr form a cerium-zirconium solid solution and play a role of a carrier by controlling the proportion of the metals, and simultaneously ensure that Ni plays a role of catalytic activity and better catalytic effect.
In the method, the membrane dispersion microreactor has small storage amount and higher flux, and is suitable for continuous and controllable production of the nanostructured catalyst.
Drawings
FIG. 1 is a flow diagram of a co-precipitation reaction using a membrane-dispersed microreactor in accordance with the present invention;
FIG. 2 is a TEM image of the catalyst prepared in example 1;
fig. 3 is a TEM image of the catalyst prepared in comparative example 1.
Detailed Description
The invention provides a preparation method of a Ni-based diesel reforming catalyst, which comprises the following steps:
in a membrane dispersion microreactor, taking a mixed salt solution of nickel salt, cerium salt and zirconium salt as a continuous phase to enter a main channel of the membrane dispersion microreactor, taking an ammonia water solution as a dispersed phase to enter a microfiltration membrane of the membrane dispersion microreactor, shearing the solution, mixing the solution with the continuous phase, and carrying out coprecipitation reaction to obtain slurry;
sequentially aging and separating the slurry to obtain a catalyst precursor;
drying, calcining and reducing the catalyst precursor in sequence to obtain the Ni-based diesel reforming catalyst;
in the cerium salt and the zirconium salt, the molar ratio of Ce to Zr is (1-9): 1, and in the nickel salt and the cerium salt, the molar ratio of Ce to Ni is (1-10): 1.
In the present invention, unless otherwise specified, all the starting materials required for the preparation are commercially available products well known to those skilled in the art.
In the membrane dispersion microreactor, mixed salt solution of nickel salt, cerium salt and zirconium salt is used as a continuous phase and enters a main channel of the membrane dispersion microreactor, and ammonia water solution is used as a dispersed phase and enters a microfiltration membrane of the membrane dispersion microreactor to be sheared and then is mixed with the continuous phase to carry out coprecipitation reaction, so that slurry is obtained. The present invention is not particularly limited with respect to the source and configuration of the membrane-dispersion microreactor, and commercially available membrane-dispersion microreactors configured as well known in the art may be used, and the present invention is limited only with respect to the size of the membrane-dispersion microreactor. In the present invention, the length of the main channel of the membrane dispersion microreactor is preferably 10mm, and the width and height thereof are independently preferably 0.5 to 2mm, and more preferably 1.0 to 1.5 mm. By controlling the membrane dispersion microreactor within the size range, the invention can increase the concentration gradient, strengthen the mass transfer effect, facilitate the preparation of highly dispersed catalyst, prevent the blockage of a channel from influencing the mass transfer and ensure the occurrence of precipitation reaction.
In the invention, the aperture of the microfiltration membrane is preferably 2-20 μm, more preferably 5-15 μm, and even more preferably 8-12 μm. According to the invention, by controlling the size of the microfiltration membrane, dispersed phase liquid drops can be controlled, and a good mass transfer effect is ensured, so that a high-dispersion Ni-based catalyst is conveniently formed, and the problems of membrane blockage, overhigh pressure drop and the like are avoided.
In the present invention, the nickel salt is preferably nickel nitrate or nickel chloride; the cerium salt is preferably cerium nitrate or cerium chloride; the zirconium salt is preferably zirconium nitrate or zirconium chloride; the total metal ion concentration of the mixed salt solution of the nickel salt, the cerium salt and the zirconium salt is preferably 0.02-2 mol/L, more preferably 0.1-1.8 mol/L, and further preferably 0.6-1.2 mol/L. The preparation process of the mixed salt solution is not particularly limited in the present invention, and the nickel salt, the cerium salt and the zirconium salt are mixed in water according to a process well known in the art.
In the present invention, the concentration of the aqueous ammonia solution is preferably 0.02 to 2mol/L, more preferably 0.1 to 1.8mol/L, and still more preferably 0.6 to 1.2 mol/L.
In the cerium salt and the zirconium salt, the molar ratio of Ce to Zr is (1-9): 1, preferably (3-8): 1, and more preferably (5-7): 1; in the nickel salt and the cerium salt, the molar ratio of Ce to Ni is (1-10): 1, preferably (3-8): 1, and more preferably (5-6): 1. The invention controls the proportion of the metal within the range, can ensure that Ce and Zr form oxides and play a role of a carrier, and simultaneously ensures that Ni plays a role of catalytic activity and ensures a better catalytic effect.
The present invention preferably employs a advection pump to introduce the continuous phase into the main channel of the membrane dispersion microreactor and to introduce the dispersed phase into the microfiltration membrane of the membrane dispersion microreactor (as shown in fig. 1). In the invention, the flow rate of the continuous phase is preferably 1-20 mL/min, more preferably 5-15 mL/min, and further preferably 8-12 mL/min; the flow rate of the dispersed phase is preferably 3-100 mL/min, more preferably 10-80 mL/min, and further preferably 30-60 mL/min; the ratio of the dispersed phase to the continuous phase (i.e., the flow ratio) is preferably 3 to 5, more preferably 3.5 to 4.5.
In the invention, the membrane dispersion microreactor is preferably placed in a water bath at 0-30 ℃ to perform the coprecipitation reaction. In the invention, the time of the coprecipitation reaction is the residence time of the mobile phase and the continuous phase in the microchannel of the membrane dispersion microreactor, the residence time is determined by the size of the microchannel, the mass transfer control of the microchannel is eliminated, and the precipitation time of the coprecipitation reaction controlled by intrinsic dynamics is in a sub-millisecond level and is not particularly limited.
In the coprecipitation reaction process, under the condition of ammonia water, metal ions in nickel salt, cerium salt and zirconium salt are coprecipitated to form metal hydroxide.
After the coprecipitation reaction is completed, the slurry is preferably collected (as shown in fig. 1) for subsequent processes. The collection process is not particularly limited in the present invention, and may be performed according to a process well known in the art. In the invention, the time for collecting the slurry is preferably 10-20 min. In the invention, the pH range of the slurry is preferably 9.0-10.0, and more preferably 9.5; according to the invention, the pH value of the slurry is adjusted by controlling the addition amount of ammonia water, so that the coprecipitation of Ce, Zr and Ni is realized.
After obtaining the slurry, the invention sequentially ages and separates the slurry to obtain the catalyst precursor. In the invention, the aging is carried out in a water bath, and the temperature of the aging is preferably 0-30 ℃, more preferably 10-25 ℃; the time is preferably 1 to 6 hours, more preferably 2 to 5 hours, and further preferably 3 to 4 hours. The invention leads the small crystal grains generated by the coprecipitation reaction to be continuously fused and grown into more stable large crystal grains through aging.
In the present invention, the separation is preferably performed by centrifugation, and the conditions of the centrifugation are not particularly limited in the present invention, and the precipitate can be separated from the liquid phase according to a procedure well known in the art.
After the separation is completed, the precipitate obtained by the separation is preferably washed with water until the washing solution has a pH of 7 and the adsorbed metal ions of Ni, Ce, and Zr are not detected, and then washed with ethanol three or more times to obtain a solid, i.e., a catalyst precursor (metal hydroxide of nickel salt, cerium salt, and zirconium salt).
After the catalyst precursor is obtained, the catalyst precursor is dried, calcined and reduced in sequence to obtain the Ni-based diesel reforming catalyst. In the invention, the drying is preferably carried out in an oven, the drying temperature is preferably 60-120 ℃, more preferably 80-100 ℃, and the drying time is preferably 6-12 hours, more preferably 8-10 hours.
In the invention, the calcination is preferably carried out in an air atmosphere, the calcination temperature is preferably 400-600 ℃, more preferably 450-550 ℃, and the calcination time is preferably 2-6 h, more preferably 3-5 h. The invention converts the metal hydroxide in the catalyst precursor into metal oxide by calcination, and simultaneously forms the metal bond interaction of the metal nickel and the zirconium cerium oxide.
In the invention, the reduction is preferably carried out in a hydrogen-nitrogen atmosphere, and the volume fraction of hydrogen in the hydrogen-nitrogen atmosphere is preferably 5-10%; the reduction temperature is preferably 400-600 ℃, and more preferably 450-550 ℃; the time is preferably 2 to 4 hours, and more preferably 2.5 to 3.5 hours. The invention reduces the nickel oxide in the metal oxide into simple substance nickel by controlling the reduction temperature.
The invention provides a Ni-based diesel reforming catalyst prepared by the preparation method in the technical scheme, which comprises a carrier and an active component loaded on the carrier, wherein the active component is nickel, the carrier is a cerium-zirconium solid solution, and the cerium-zirconium solid solution is CexZr1-xO2Wherein x is 0.5-0.9; the active component accounts for 3-25% by mass. In the Ni-based catalyst prepared by the method, Ni is dispersed more uniformly, active metals with equal mass fractions have more active sites, so that the activity of the catalyst can be improved, and Zr is contained in CeO2The medium doping is more uniform, more oxygen vacancies are formed, and the coking can be inhibited.
In the present invention, the active component forms a Strong Metal Support Interaction (SMSI) with the support, and the Ni — Rh alloy is highly dispersed in the support.
In the invention, the particle size of Ni in the Ni-based diesel reforming catalyst is preferably 4-5 nm; in the invention, x is preferably 0.6-0.8, and the mass percentage of the active component is preferably 5-15%, more preferably 8-12%, and even more preferably 10%.
The invention provides the application of the Ni-based diesel reforming catalyst in the technical scheme in the preparation of hydrogen by diesel reforming. In the invention, the application method is preferably that the Ni-based diesel reforming catalyst is filled in a micro-filled column with the inner diameter of 3-8 mm, diesel steam and water steam are used as reactants to carry out steam reforming reaction, and the obtained reaction product enters a gas chromatography for on-line analysis.
In the present invention, the temperature of the steam reforming reaction is preferably 650 ℃; the water-carbon ratio is preferably 4; the preferred diesel reforming hourly space velocity is 4.5-18 h-1。
The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Respectively filling a mixed salt solution (total ion concentration is 0.2mol/L, Ce: Zr: Ni molar ratio is 42:14:17) of nickel nitrate, cerium nitrate and zirconium nitrate and an aqueous ammonia solution (0.2mol/L) into two conical flasks, placing a membrane dispersion microreactor into a water bath at 30 ℃, taking the mixed salt solution as a continuous phase to enter a main channel (length is 10mm, width and height are 1mm), taking the aqueous ammonia solution as a dispersed phase, shearing the aqueous ammonia solution through a microfiltration membrane (aperture is 5 mu m) of the membrane dispersion microreactor, then mixing the aqueous ammonia solution with the continuous phase in the main channel, and carrying out coprecipitation reaction; wherein the continuous phase flow is 10mL/min, the dispersed phase flow is 40mL/min, the phase ratio of the dispersed phase to the continuous phase is 4, slurry (pH value is 9.5) is obtained within 20min, and the slurry is collected in a beaker;
mixing the slurryAging the solution in a water bath at 30 ℃ for 2h, centrifugally separating the obtained material, washing the separated precipitate with water until the pH of the washing solution is 7 and no adsorbed Ni, Ce and Zr metal ions can be detected, washing with ethanol for more than three times to obtain a catalyst precursor, drying the catalyst precursor in an oven at 100 ℃ for 12h, placing the dried catalyst precursor in an air atmosphere, calcining at 450 ℃ for 4h, and reducing at 450 ℃ for 4h in a hydrogen-nitrogen atmosphere (the volume fraction of hydrogen is 10%) to obtain a Ni-based diesel reforming catalyst (the composition of the carrier cerium-zirconium solid solution is Ce) and the catalyst is prepared by carrying out reduction at 450 ℃ for 4hxZr1-xO2X is 0.75, and the mass percentage of the active component Ni is 10%).
Example 2
Respectively filling a mixed salt solution (total ion concentration is 0.4mol/L, Ce: Zr: Ni molar ratio is 42:14:17) of nickel nitrate, cerium nitrate and zirconium nitrate and an aqueous ammonia solution (0.4mol/L) into two conical flasks, placing a membrane dispersion microreactor into a water bath at 30 ℃, taking the mixed salt solution as a continuous phase to enter a main channel (length is 10mm, width and height are 1mm), taking the aqueous ammonia solution as a dispersed phase, shearing the aqueous ammonia solution through a microfiltration membrane (aperture is 5 mu m) of the membrane dispersion microreactor, then mixing the aqueous ammonia solution with the continuous phase in the main channel, and carrying out coprecipitation reaction; wherein the continuous phase flow is within 10mL/min, the dispersed phase flow is within 40mL/min, the phase ratio of the dispersed phase to the continuous phase is 4, slurry (pH value is 9.5) is obtained within 20min, and the slurry is collected in a beaker;
aging the slurry in a water bath at 30 ℃ for 2h, centrifugally separating the obtained material, washing the separated precipitate with water until the pH of the washing solution is 7 and no adsorbed Ni, Ce and Zr metal ions can be detected, washing with ethanol for more than three times to obtain a catalyst precursor, drying the catalyst precursor in a drying oven at 100 ℃ for 12h, then placing the dried catalyst precursor in an air atmosphere, calcining at 450 ℃ for 4h, and then reducing at 450 ℃ for 4h in a hydrogen-nitrogen atmosphere (the volume fraction of hydrogen is 10%) to obtain a Ni-based diesel reforming catalyst, wherein the composition of the carrier cerium-zirconium solid solution is CexZr1-xO2X is 0.75, and the mass percentage of the active component Ni is 10%).
Example 3
Respectively filling a mixed salt solution (total ion concentration is 0.2mol/L, Ce: Zr: Ni molar ratio is 39:13:26) of nickel nitrate, cerium nitrate and zirconium nitrate and an aqueous ammonia solution (0.2mol/L) into two conical flasks, placing a membrane dispersion microreactor into a water bath at 30 ℃, taking the mixed salt solution as a continuous phase to enter a main channel (length is 10mm, width and height are 1mm), taking the aqueous ammonia solution as a dispersed phase, shearing the aqueous ammonia solution through a microfiltration membrane (aperture is 5 mu m) of the membrane dispersion microreactor, then mixing the aqueous ammonia solution with the continuous phase in the main channel, and carrying out coprecipitation reaction; wherein the continuous phase flow is within 20mL/min, the dispersed phase flow is within 80mL/min, the phase ratio of the dispersed phase to the continuous phase is 4, slurry (pH value is 9.5) is obtained within 10min, and the slurry is collected in a beaker;
aging the slurry in a water bath at 30 ℃ for 2h, centrifugally separating the obtained material, washing the separated precipitate with water until the pH of the washing solution is 7 and no adsorbed Ni, Ce and Zr metal ions can be detected, washing with ethanol for more than three times to obtain a catalyst precursor, drying the catalyst precursor in a drying oven at 100 ℃ for 12h, then placing the dried catalyst precursor in an air atmosphere, calcining at 450 ℃ for 4h, and then reducing at 450 ℃ for 4h in a hydrogen-nitrogen atmosphere (the volume fraction of hydrogen is 10%) to obtain a Ni-based diesel reforming catalyst, wherein the composition of the carrier cerium-zirconium solid solution is CexZr1-xO2X is 0.75, and the mass percentage of the active component Ni is 15%).
Example 4
Respectively filling a mixed salt solution (total ion concentration is 0.2mol/L, Ce: Zr: Ni molar ratio is 42:14:17) of nickel nitrate, cerium nitrate and zirconium nitrate and an aqueous ammonia solution (0.2mol/L) into two conical flasks, placing a membrane dispersion microreactor into a water bath at 30 ℃, taking the mixed salt solution as a continuous phase to enter a main channel (length is 10mm, width and height are 1mm), taking the aqueous ammonia solution as a dispersed phase, shearing the aqueous ammonia solution through a microfiltration membrane (aperture is 5 mu m) of the membrane dispersion microreactor, then mixing the aqueous ammonia solution with the continuous phase in the main channel, and carrying out coprecipitation reaction; wherein the continuous phase flow is within 20mL/min, the dispersed phase flow is within 80mL/min, the phase ratio of the dispersed phase to the continuous phase is 4, slurry (pH value is 9.5) is obtained within 10min, and the slurry is collected in a beaker;
the slurry was placed in a 30 ℃ water bathAging for 2h, performing centrifugal separation on the obtained material, washing the separated precipitate with water until the pH of the washing solution is 7 and no adsorbed Ni, Ce and Zr metal ions can be detected, washing with ethanol for more than three times to obtain a catalyst precursor, drying the catalyst precursor in a 100 ℃ oven for 12h, placing the dried catalyst precursor in an air atmosphere, calcining at 450 ℃ for 4h, and reducing at 450 ℃ for 4h in a hydrogen-nitrogen atmosphere (the volume fraction of hydrogen is 10%) to obtain a Ni-based diesel reforming catalyst, wherein the carrier cerium-zirconium solid solution comprises CexZr1-xO2X is 0.75, and the mass percentage of the active component Ni is 10%).
Comparative example 1
Adding a mixed salt solution of nickel nitrate, cerium nitrate and zirconium nitrate (Ce: Zr: Ni molar ratio 42:14:17) into a stirring kettle at 25 ℃, dropwise adding ammonia water under the condition of stirring (stirring speed is 400rpm) to realize the blending of alkali liquor and the salt solution, stopping dropwise adding and stirring until the pH value of the obtained suspension reaches 9.5, carrying out coprecipitation reaction for 90min, aging the obtained catalyst precursor for 2h, sequentially centrifuging the obtained product, drying at 100 ℃ for 12h, calcining at 450 ℃ for 4h in an air atmosphere, and reducing at 450 ℃ for 4h in a hydrogen-nitrogen atmosphere (the volume fraction of hydrogen is 10%) to obtain the catalyst.
Characterization of
TEM tests were performed on the catalysts prepared in example 1 and comparative example 1, and the results are shown in fig. 2 and fig. 3, respectively; as can be seen from fig. 2 to 3, compared to the comparative example (conventional stirring method), the particle size of nickel in the catalyst prepared in example 1 is 4.5nm, and the particle size of nickel in the catalyst prepared in comparative example 1 is about 6.5nm, and the active metal particles of the catalyst prepared by the membrane-dispersed micro-reaction of the present invention are uniformly dispersed and have a small particle size.
Application example
The catalysts prepared in the example 1 and the comparative example 1 are filled in a micro-filled column with the inner diameter of 3-8 mm, reactants are diesel steam and water steam, the steam reforming reaction is carried out under the conditions of 650 ℃ reaction temperature and 4 water-carbon ratio according to the conditions of the table 1, reaction products enter a gas chromatograph for on-line analysis, and the hydrogen yield is calculated, and the results are shown in the table 1.
Table 1 hydrogen yield data for catalysts prepared in example 1 and comparative example 1 under different conditions
Figure BDA0002786902700000091
Figure BDA0002786902700000101
Figure BDA0002786902700000111
As can be seen from table 1, compared with the conventional stirring method for preparing a Ni-based catalyst, the co-precipitation reaction performed in the membrane dispersion microreactor of the present invention can significantly improve the catalytic performance of the catalyst, thereby increasing the hydrogen yield.
Performance testing
The catalysts prepared in example 1 and comparative example 1 were subjected to performance test by a CO pulse adsorption method to verify the degree of dispersion of active metals, the method comprising:
the catalysts prepared in example 1 and comparative example 1 were packed in a quartz tube reactor having an inner diameter of 4mm at 10% H2Heating to 450 ℃ from room temperature at a heating rate of 10 ℃/min in a mixed gas/He atmosphere (the gas flow is 30mL/min), and keeping the temperature at 450 ℃ for 1 h; switching gas to He (flow rate is 50mL/min) atmosphere at 450 ℃, and purging for 30min for degassing; cooling to room temperature under He atmosphere, injecting 10% CO/He into He atmosphere with flow rate of 50mL/min, performing CO chemisorption, detecting the amount of outlet CO by chromatography TCD, and calculating the catalyst chemisorption amount, the results are shown in Table 2.
Table 2 chemisorption amounts of catalysts prepared in example 1 and comparative example 1
Catalyst and process for preparing same Amount of chemisorption (. mu. mol/g)
Example 1 100.5
Comparative example 1 65.4
As can be seen from table 2, the catalyst prepared according to the present invention has a significantly higher chemisorption amount of CO than comparative example 1, indicating that the catalyst prepared according to the present invention has a high degree of dispersion of the active metal (Ni) and a small particle size.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims (10)

1. A preparation method of a Ni-based diesel reforming catalyst is characterized by comprising the following steps:
in a membrane dispersion microreactor, taking a mixed salt solution of nickel salt, cerium salt and zirconium salt as a continuous phase to enter a main channel of the membrane dispersion microreactor, taking an ammonia water solution as a dispersed phase to enter a microfiltration membrane of the membrane dispersion microreactor, shearing the solution, mixing the solution with the continuous phase, and carrying out coprecipitation reaction to obtain slurry;
sequentially aging and separating the slurry to obtain a catalyst precursor;
drying, calcining and reducing the catalyst precursor in sequence to obtain the Ni-based diesel reforming catalyst;
in the cerium salt and the zirconium salt, the molar ratio of Ce to Zr is (1-9): 1, and in the nickel salt and the cerium salt, the molar ratio of Ce to Ni is (1-10): 1.
2. The method according to claim 1, wherein the mixed salt solution of nickel salt, cerium salt and zirconium salt has a total metal ion concentration of 0.02 to 2 mol/L; the concentration of the ammonia water solution is 0.02-2 mol/L.
3. The method of claim 1, wherein the main channel has a length of 10mm, a width and a height of 0.5 to 2mm independently; the aperture of the microfiltration membrane is 2-20 mu m.
4. The method according to claim 1, wherein the flow rate of the continuous phase is 1 to 20mL/min, the flow rate of the dispersed phase is 3 to 100mL/min, and the flow rate ratio of the dispersed phase to the continuous phase is 3 to 5.
5. The preparation method according to claim 1, wherein the membrane dispersion microreactor is placed in a water bath at 0 to 30 ℃ to perform the coprecipitation reaction.
6. The method according to claim 1, wherein the aging is carried out at a temperature of 0 to 30 ℃ for 1 to 6 hours.
7. The preparation method according to claim 1, wherein the calcination is carried out in an air atmosphere, the calcination temperature is 400-600 ℃, and the calcination time is 2-6 h; the reduction temperature is 400-600 ℃, and the reduction time is 2-4 h.
8. The Ni-based diesel reforming catalyst prepared by the preparation method of any one of claims 1 to 7, which is characterized by comprising a carrier and an active component loaded on the carrier, wherein the active component is nickel, the carrier is a cerium-zirconium solid solution, and the cerium-zirconium solid solution is CexZr1-xO2Wherein x = 0.5-0.9; the active component accounts for 3-25% by mass.
9. The Ni-based diesel reforming catalyst according to claim 8, wherein x = 0.6-0.8, and the active component is 5-15% by mass.
10. Use of the Ni-based diesel reforming catalyst of claim 8 or 9 in diesel reforming to produce hydrogen.
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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1318429A (en) * 2001-04-20 2001-10-24 清华大学 Membrane dispersion process of preparing superfine particle
CN101444740A (en) * 2008-12-16 2009-06-03 中国科学院广州能源研究所 Catalyst for hydrogen production by bio-oil steam reforming and preparation method thereof
CN101829578A (en) * 2010-05-20 2010-09-15 浙江大学 Catalyst for catalyzing and reforming biologic oil to prepare hydrogen and preparation method thereof
CN103553116A (en) * 2013-08-12 2014-02-05 清华大学 Nanometer zinc oxide particle preparation method
CN104841437A (en) * 2015-04-05 2015-08-19 浙江大学 Method for preparing copper-zinc catalyst by using micro-channel reactor
CN106348325A (en) * 2016-11-11 2017-01-25 清华大学 Gamma-alumina and preparation method thereof
KR20170047815A (en) * 2015-10-23 2017-05-08 영남대학교 산학협력단 Catalyst for Steam Reformation
CN109279640A (en) * 2018-11-27 2019-01-29 清华大学 A kind of barium sulfate material and preparation method thereof

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1318429A (en) * 2001-04-20 2001-10-24 清华大学 Membrane dispersion process of preparing superfine particle
CN101444740A (en) * 2008-12-16 2009-06-03 中国科学院广州能源研究所 Catalyst for hydrogen production by bio-oil steam reforming and preparation method thereof
CN101829578A (en) * 2010-05-20 2010-09-15 浙江大学 Catalyst for catalyzing and reforming biologic oil to prepare hydrogen and preparation method thereof
CN103553116A (en) * 2013-08-12 2014-02-05 清华大学 Nanometer zinc oxide particle preparation method
CN104841437A (en) * 2015-04-05 2015-08-19 浙江大学 Method for preparing copper-zinc catalyst by using micro-channel reactor
KR20170047815A (en) * 2015-10-23 2017-05-08 영남대학교 산학협력단 Catalyst for Steam Reformation
CN106348325A (en) * 2016-11-11 2017-01-25 清华大学 Gamma-alumina and preparation method thereof
CN109279640A (en) * 2018-11-27 2019-01-29 清华大学 A kind of barium sulfate material and preparation method thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Ni Catalysts Supported on Modified Alumina for Diesel Steam Reforming;Antonios Tribalis et al.;《Catalysts》;20160113;第1页摘要 *

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