CN111841623A - Molecular sieve catalyst, preparation method and application thereof - Google Patents

Molecular sieve catalyst, preparation method and application thereof Download PDF

Info

Publication number
CN111841623A
CN111841623A CN202010836163.9A CN202010836163A CN111841623A CN 111841623 A CN111841623 A CN 111841623A CN 202010836163 A CN202010836163 A CN 202010836163A CN 111841623 A CN111841623 A CN 111841623A
Authority
CN
China
Prior art keywords
molecular sieve
sieve catalyst
solution
catalyst
metal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202010836163.9A
Other languages
Chinese (zh)
Other versions
CN111841623B (en
Inventor
田亚杰
段浩南
乔聪震
杨浩
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Henan University
Original Assignee
Henan University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Henan University filed Critical Henan University
Priority to CN202010836163.9A priority Critical patent/CN111841623B/en
Publication of CN111841623A publication Critical patent/CN111841623A/en
Application granted granted Critical
Publication of CN111841623B publication Critical patent/CN111841623B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J29/00—Catalysts comprising molecular sieves
    • B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
    • B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
    • B01J29/70—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of types characterised by their specific structure not provided for in groups B01J29/08 - B01J29/65
    • B01J29/72—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of types characterised by their specific structure not provided for in groups B01J29/08 - B01J29/65 containing iron group metals, noble metals or copper
    • B01J29/74—Noble metals
    • B01J29/7415—Zeolite Beta
    • B01J35/23—
    • B01J35/393—
    • B01J35/615—
    • B01J35/617—
    • B01J35/633—
    • B01J35/635—
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/0009—Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
    • B01J37/0018—Addition of a binding agent or of material, later completely removed among others as result of heat treatment, leaching or washing,(e.g. forming of pores; protective layer, desintegrating by heat)
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/08—Heat treatment
    • B01J37/082—Decomposition and pyrolysis
    • B01J37/088—Decomposition of a metal salt
    • 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
    • B01J37/10—Heat treatment in the presence of water, e.g. steam
    • 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
    • B01J37/30—Ion-exchange
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C4/00—Preparation of hydrocarbons from hydrocarbons containing a larger number of carbon atoms
    • C07C4/02—Preparation of hydrocarbons from hydrocarbons containing a larger number of carbon atoms by cracking a single hydrocarbon or a mixture of individually defined hydrocarbons or a normally gaseous hydrocarbon fraction
    • C07C4/06—Catalytic processes
    • 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
    • B01J2229/00—Aspects of molecular sieve catalysts not covered by B01J29/00
    • B01J2229/10—After treatment, characterised by the effect to be obtained
    • B01J2229/18—After treatment, characterised by the effect to be obtained to introduce other elements into or onto the molecular sieve itself
    • B01J2229/183—After treatment, characterised by the effect to be obtained to introduce other elements into or onto the molecular sieve itself in framework positions
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C2529/00—Catalysts comprising molecular sieves
    • C07C2529/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites, pillared clays
    • C07C2529/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
    • C07C2529/70—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of types characterised by their specific structure not provided for in groups C07C2529/08 - C07C2529/65
    • C07C2529/72—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of types characterised by their specific structure not provided for in groups C07C2529/08 - C07C2529/65 containing iron group metals, noble metals or copper
    • C07C2529/74—Noble metals
    • 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 molecular sieve catalyst, a preparation method and application thereof. The molecular sieve catalyst comprises: a molecular sieve support having an average particle size of 50-500nm, the molecular sieve support having a BEA structure; and an active ingredient which is a metal and/or a metal oxide, the active ingredient having an average particle diameter of 0.5 to 4 nm; wherein at least 95% or more of the active ingredient, based on the total mass of the active ingredient, is located inside the molecular sieve support. The molecular sieve catalyst of the invention effectively improves the molecular mass transfer diffusion rate by utilizing the regular pore canal and cage structure of the BEA structure molecular sieve, thereby improving the reaction rate of catalytic reaction and improving the reaction activity of the catalytic reaction; and the characteristics of multiple active sites and highly ordered dispersion of metal particles make the catalyst material have excellent performances in the aspects of catalytic cracking, catalytic oxidation, isomerization and the like.

Description

Molecular sieve catalyst, preparation method and application thereof
Technical Field
The invention relates to a molecular sieve catalyst, a preparation method and application thereof, in particular to a BEA structure molecular sieve catalyst packaged with metal oxide nanoparticles or metal nanoparticles, a preparation method and application thereof, belonging to the field of catalysts.
Background
The metal nanoparticles have high catalytic activity for hydrogenation (deoxidation) reaction, oxidation reaction or reduction of nitrogen oxides, hydrocarbons and the like. Studies suggest that when the metal particle size is decreased, the catalytic activity is increased, and when the nano metal particle size is less than 5nm, the catalytic activity is significantly enhanced. These very small sized metal nanoparticles generally have a low average coordination number, are mostly distributed at the corners and edges of the support, and participate in the catalytic reaction process after activation. However, the thermal stability of metal nanoparticles is relatively low, and even if the metal particles are supported on a carrier, sintering agglomeration may still occur at high temperature, resulting in deactivation of the catalyst, which is one of the most important reasons for limiting the industrial application thereof.
Theoretically, the above problem may be able to be solved by confining the metal nanoparticles in the pores or cavities of the support. The metal nanoparticles are limited in the pore channels or cavities of the carrier, so that the agglomeration of the metal nanoparticles in the synthesis and reaction processes can be effectively avoided, and meanwhile, the carrier is required to have proper pore channels or cavities to allow the diffusion of reactants and products and simultaneously contact with the metal nanoparticles.
However, since the shell itself is usually of a mesoporous structure, it is difficult to prepare core-shell encapsulated metal nanoparticles of a microporous structure; in addition, obtaining metal nanoparticles with a particle size of less than 5nm and preventing the metal nanoparticles from leaching from the interior of the shell are problems to be solved.
Disclosure of Invention
Problems to be solved by the invention
In view of the technical problems in the prior art, an object of the present invention is to provide a molecular sieve pore structure of a molecular sieve catalyst to limit clusters of metal particles, increase the contact area between a metal and a reactant in a catalytic reaction and the active center of the molecular sieve, and further improve the contact between metal oxide nanoparticles or metal nanoparticles and reactant molecules by using the characteristics and the shape selection property of the molecular sieve regular pore, thereby greatly improving the activity and selectivity of the catalyst in the catalytic reaction, and achieving a high catalytic effect with only a low metal loading amount.
Furthermore, the invention also provides a preparation method of the molecular sieve catalyst, which is simple and feasible, has easily obtained raw materials and is suitable for mass production.
Means for solving the problems
The invention first provides a molecular sieve catalyst comprising:
a molecular sieve support having an average particle size of 50-500nm, the molecular sieve support having a BEA structure; and
the active ingredient is metal and/or metal oxide, and the average particle size of the active ingredient is 0.5-4 nm; wherein
At least 95% or more of the active ingredient, based on the total mass of the active ingredient, is located inside the molecular sieve support.
The molecular sieve catalyst provided by the invention is characterized in that the content of the active component is 0.01-5% of the total mass of the molecular sieve catalyst.
The molecular sieve catalyst according to the present invention, wherein the metal element in the active component is one or a combination of two or more of platinum, palladium, ruthenium, gold, and zinc.
The molecular sieve catalyst provided by the invention has the specific surface area of 250-700m2Per g, pore volume of 0.4-0.8cm3/g。
The invention also provides a preparation method of the molecular sieve catalyst, which comprises the following steps:
mixing a silicon source, a template agent, an optional alkali source and an optional aluminum source in a solvent to obtain a precursor solution;
carrying out hydrothermal crystallization treatment on the precursor solution to obtain a hydrothermal crystallization product;
removing less than 70 mass percent of template agent from the hydrothermal crystallization product to obtain an intermediate product, wherein the intermediate product is calculated by the total mass of the template agent;
and (3) carrying out ion exchange treatment on the intermediate product by using a solution containing metal elements in the active components, and then roasting to remove the template agent to obtain the molecular sieve catalyst.
The preparation method of the molecular sieve catalyst comprises the following steps of (1) preparing a template agent, wherein the template agent comprises a quaternary ammonium salt surfactant, preferably the quaternary ammonium salt surfactant comprises tetraethylammonium hydroxide;
the aluminum source comprises NaAlO2、Al(NO3)3、Al2(SO4)3、AlCl3Or Al (OCH (CH)3)2)3One or a combination of two or more of them;
the silicon source comprises one or the combination of more than two of silica sol, ethyl orthosilicate or sodium silicate;
the alkali source comprises sodium hydroxide or potassium hydroxide.
The preparation method of the molecular sieve catalyst comprises the step of preparing the precursor solution containing SiO2Template agent, Al2O3Basic oxide and H2The molar ratio of O is 100 (2-20): (0-50): (0-10): 2000-6000);
the temperature of the hydrothermal crystallization treatment is 130-170 ℃, and the time of the hydrothermal crystallization treatment is 2-15 days.
According to the preparation method of the molecular sieve catalyst, acid solution is used for carrying out acid washing treatment on the hydrothermal crystallization product, so that part of template agent in the hydrothermal crystallization product is removed;
preferably, the acid solution is an aqueous acetic acid solution; more preferably, the mass fraction of the acetic acid aqueous solution is 20-80%; and/or
The temperature of the acid washing treatment is 20-120 ℃; the time of the acid cleaning treatment is 4-24 h.
The preparation method of the molecular sieve catalyst comprises the following steps of (1) carrying out ion exchange treatment at the temperature of 20-120 ℃ for 2-24 h;
the roasting is carried out in an oxygen-containing atmosphere and/or a hydrogen-containing atmosphere, the roasting temperature is 300-600 ℃, and the roasting time is 4-12 h.
The invention also provides application of the molecular sieve catalyst or the molecular sieve catalyst prepared by the preparation method in catalytic hydrogenation, catalytic deoxidation, catalytic oxidation or catalytic dehydrogenation reaction.
ADVANTAGEOUS EFFECTS OF INVENTION
The molecular sieve catalyst of the invention effectively improves the molecular mass transfer diffusion rate by utilizing the regular pore canal and cage structure of the BEA structure molecular sieve, thereby improving the reaction rate of catalytic reaction and improving the reaction activity of the catalytic reaction; and the characteristics of multiple active sites and highly ordered dispersion of metal particles make the catalyst material have excellent performances in the aspects of catalytic cracking, catalytic oxidation, isomerization and the like.
Furthermore, the preparation method is simple and feasible, the raw materials are easy to obtain, and the metal particles can be uniform in size, uniform in dispersion and certain in lattice regularity, so that the preparation method is suitable for mass production.
Further, the molecular sieve catalyst of the present invention can be used for catalyzing hydrodeoxygenation reactions.
Drawings
FIG. 1 is a TEM image of a sample of the molecular sieve catalyst prepared in example 1;
FIG. 2 is a TEM image of a sample of the molecular sieve catalyst prepared in example 8;
FIG. 3 is a TEM image of a sample of the molecular sieve catalyst prepared in example 12;
FIG. 4 is a TEM image of a sample of the molecular sieve catalyst prepared in example 15;
FIGS. 5A, 5B, and 5C are XRD patterns of samples of molecular sieve catalysts prepared in examples 16, 17, and 18, respectively;
FIG. 6 is a TEM image of a sample of the molecular sieve catalyst prepared in example 16;
FIGS. 7A and 7B are XRD patterns of samples of example 21 and example 22, respectively;
FIG. 8 is a TEM image of a sample of the molecular sieve catalyst prepared in example 23;
FIG. 9 is a graph showing the comparative effect of example 26 in catalyzing the complete oxidation of toluene;
FIG. 10 is a graph of the comparative effect of example 27 on the catalysis of n-heptane hydroisomerization reactions;
FIG. 11 is a graph showing the comparative effect of example 28 on catalyzing the reaction of hydrogen and oxygen to synthesize hydrogen peroxide;
FIG. 12 is a graph showing the comparative effect of example 29 on the catalytic hydrocracking of n-decane;
figure 13 is a graph of the comparative effect of example 30 on the catalytic hydrodeoxygenation of guaiacol.
Detailed Description
The present invention will be described in detail below. The technical features described below are explained based on typical embodiments and specific examples of the present invention, but the present invention is not limited to these embodiments and specific examples. It should be noted that:
in the present specification, the numerical range represented by "numerical value a to numerical value B" means a range including the end point numerical value A, B.
In the present specification, "plural" in "plural", and the like means a numerical value of 2 or more unless otherwise specified.
In the present specification, "%" denotes mass% unless otherwise specified.
In the present specification, the meaning of "may" includes both the meaning of performing a certain process and the meaning of not performing a certain process.
In this specification, "optional" or "optionally" means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not.
In the present specification, reference to "some particular/preferred embodiments," "other particular/preferred embodiments," "embodiments," and the like, means that a particular element (e.g., feature, structure, property, and/or characteristic) described in connection with the embodiment is included in at least one embodiment described herein, and may or may not be present in other embodiments. In addition, it is to be understood that the described elements may be combined in any suitable manner in the various embodiments.
The temperature referred to herein as "room temperature" is generally between "10-40 ℃.
First aspect
A first aspect of the invention provides a molecular sieve catalyst comprising:
a molecular sieve support having an average particle size of 50-500nm, the molecular sieve support having a BEA structure; and
the active ingredient is metal and/or metal oxide, and the average particle size of the active ingredient is 0.5-4 nm; wherein
At least 95% or more of the active ingredient, based on the total mass of the active ingredient, is located inside the molecular sieve support.
The molecular sieve catalyst of the invention effectively improves the molecular mass transfer diffusion rate by utilizing the regular pore canal and cage structure of the BEA structure molecular sieve, thereby improving the reaction rate of catalytic reaction and improving the reaction activity of the catalytic reaction; and the characteristics of multiple active sites and highly ordered dispersion of metal particles make the catalyst material have excellent performances in the aspects of catalytic cracking, catalytic oxidation, isomerization and the like.
Further, in the present invention, the molecular sieve catalyst has a specific surface area of 250-700m2Per g, pore volume of 0.4-0.8cm3(ii) in terms of/g. Molecules of the inventionThe sieve catalyst has high specific surface area and pore volume, and is a molecular sieve catalyst with excellent performance.
Molecular sieve carrier
Natural zeolite is a typical porous material, and has been widely used in the fields of catalysis, adsorption separation, biotechnology, etc. due to its morphology, adjustable structure, high hydrothermal stability and suitable acidity. Zeolite molecular sieves have two major structural advantages: firstly, the specific pore channel size ensures that the porous membrane has the function of selective adsorption; secondly, the surface acidity with certain intensity. The inventor of the invention knows that compared with a mesoporous core-shell structure, the zeolite molecular sieve has a determined topological crystal structure, and provides possibility for packaging metal nanoparticles in a pore channel or a cage.
The pore channels of the zeolite structure are formed by connecting relatively large cavities with each other through sub-nanometer windows, so that when metal nanoparticles are gathered to a certain volume after entering the cavities or pore channels, the metal particles with large diameters are difficult to overflow from the cavity structures again. For example, zeolite Y and X, having FAU topology, have internal cavities with a diameter of 1.2nm and openings with a diameter of 0.74 nm. Therefore, the metal nanoparticles encapsulated in the zeolite molecular sieve can effectively prevent the metal particles from sintering under severe reaction conditions, can also prevent the catalyst from being poisoned under specific reaction conditions, and simultaneously changes the selectivity of a plurality of catalytic reactions.
Due to the abundant pore characteristics of the zeolite molecular sieve, the loading density of the metal nanoparticles can be obviously improved; meanwhile, the molecular sieve has abundant surface acid sites, so that the molecular sieve becomes a typical bifunctional catalyst with metal active sites and acid functions. The bifunctional catalysts usually have a synergistic effect, and the bifunctional characteristics are obviously enhanced by the limiting effect of the zeolite molecular sieve on the metal nanoparticles and the interaction between the metal and the carrier.
The molecular sieve carrier has an average particle size of 50-500nm, and has a BEA structure. The molecular sieve catalyst of the invention effectively improves the molecular mass transfer diffusion rate by utilizing the regular pore canal and cage structure of the molecular sieve with BEA structure, thereby improving the reaction rate of catalytic reaction and improving the reaction activity of catalytic reaction; and the characteristics of multiple active sites and highly ordered dispersion of metal particles make the catalyst material have excellent performances in the aspects of catalytic cracking, catalytic oxidation, isomerization and the like.
Active ingredient
The active ingredient of the invention is metal and/or metal oxide, and the average particle size of the active ingredient is 0.5-4 nm. Most of active ingredients of the invention can be encapsulated in the molecular sieve pore canal or the cage with the regular BEA structure, the active ingredients are uniformly dispersed in the molecular sieve and form a highly ordered distribution state, meanwhile, the cluster of the active ingredients is limited by the pore canal structure of the molecular sieve, the contact area of metal and reactants in catalytic reaction and the active center of the molecular sieve are increased, meanwhile, the contact between the active ingredients and the reactant molecules is further improved by utilizing the regular pore canal characteristic and the shape selection property of the molecular sieve, the activity and the selectivity of the active ingredients in the catalytic reaction are greatly improved, and the high catalytic effect can be achieved only by lower metal loading.
Specifically, at least 95% or more of the active ingredient, based on the total mass of the active ingredient, is located inside the molecular sieve support, for example: more than 96%, more than 97%, more than 98%, more than 99%, 100% of the active ingredients are positioned in the molecular sieve carrier. In some preferred embodiments, the active ingredient may be located within the interior of the molecular sieve support.
Specifically, in the present invention, the content of the active ingredient is 0.01 to 5% based on the total mass of the molecular sieve catalyst, and for example, the amount of the active ingredient added may be 0.1%, 0.4%, 0.8%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, etc. Although the adding amount of the active ingredients is small, the more excellent catalytic effect can be achieved.
Specifically, in the present invention, the metal element of the active ingredient of the present invention is not particularly limited, and may be some metal elements commonly used in the art. Specifically, the metal element is one or a combination of two or more of platinum, palladium, ruthenium, gold and zinc.
Second aspect of the invention
A second aspect of the invention provides a process for the preparation of a molecular sieve catalyst according to the first aspect of the invention, comprising the steps of:
mixing a silicon source, a template agent, an optional alkali source and an optional aluminum source in a solvent to obtain a precursor solution;
carrying out hydrothermal crystallization treatment on the precursor solution to obtain a hydrothermal crystallization product;
removing less than 70 mass percent of template agent from the hydrothermal crystallization product to obtain an intermediate product, wherein the intermediate product is calculated by the total mass of the template agent;
and (3) carrying out ion exchange treatment on the intermediate product by using a salt solution of the active component, and then roasting to remove the template agent to obtain the molecular sieve catalyst.
Precursor solution
In some embodiments of the present invention, the silicon source may be silica gel, fumed silica, inorganic silicate, organosilicate, silica or silicic acid or any mixture thereof. In some specific embodiments, the silicon source comprises one or a combination of two or more of silica sol, ethyl orthosilicate, or sodium silicate.
As the aluminum source usable in the present invention, one or more of organoaluminum compounds, pseudo-boehmite, aluminum gel, and organic acid salts, inorganic acid salts or complexes thereof and hydrates containing aluminum may be mentioned. Preferably, the aluminium source of the present invention may be selected from pseudo-boehmite, alumina, aluminium gel, sodium aluminate, aluminium phosphate, aluminium chloride, aluminium sulphate, aluminium nitrate, aluminium isopropoxide or aluminium hydroxide or any mixture thereof. In some specific embodiments, the aluminum source comprises NaAlO2、Al(NO3)3、Al2(SO4)3、AlCl3Or Al (OCH (CH)3)2)3One or a combination of two or more of them.
In the present invention, the optional alkali source may be any available alkaline material in the art, and in some specific embodiments, the alkali source comprises sodium hydroxide or potassium hydroxide.
In the present invention, the templating agent also plays an important role. In general, crystalline materials in either the amorphous or dense phase may be obtained in the absence of a templating agent. The template agent has the main function of structure guiding, different template agents are adopted to have obvious influence on the formed framework structure and the product property, and meanwhile, the template agent can also control the distribution of silicon on the framework.
For the templating agent useful in the present invention, it may be a nitrogen or amine containing compound commonly used in the art, and typically may be N, N-diisopropylethylamine, polyethylene polyamine, morpholine, diethylamine, triethylamine, N-propylamine, isopropylamine, morpholine, piperidine, piperazine, tetraethylammonium hydroxide, or any mixture thereof. In the present invention, it is preferable to use a quaternary ammonium salt surfactant containing nitrogen or amines, and specifically, the quaternary ammonium salt surfactant includes tetraethylammonium hydroxide.
As the solvent, the present invention is not particularly limited, and may be any solvent that can be used in the art, for example: polar solvents such as water or alcohols. Water is preferably used as the solvent.
Further, in the present invention, in the precursor solution, SiO is present2Template agent, Al2O3Basic oxide and H2The molar ratio of O is 100 (2-20): (0-50): (0-10): 2000-6000);
further, the silicon source, the template agent, the optional alkali source and the optional aluminum source are mixed in a solvent to obtain a precursor solution.
The mixing mode of the silicon source, the template, the optional alkali source, and the optional aluminum source is not particularly limited in the present invention. In view of ease of handling, in some embodiments of the present invention, the silicon source, templating agent, optional base source, and optional aluminum source may be added to the solvent and mixed thoroughly. The solvent used in the present invention is not particularly limited, and may be any polar solvent commonly used in the art, for example: water, and the like.
Generally, the mixing may be performed at normal temperature, and specifically, the mixture may be stirred at room temperature for 24 to 48 hours, so as to obtain a crystallization liquid, i.e., a precursor solution.
Step of hydrothermal crystallization
And carrying out hydrothermal crystallization treatment on the precursor solution to obtain a hydrothermal crystallization product. Specifically, the obtained precursor solution is placed in a hydrothermal reaction kettle for hydrothermal crystallization treatment to obtain a hydrothermal crystallization product. Preferably, such a hydrothermal reaction vessel may be a closed hydrothermal reaction vessel, for example, a stainless steel hydrothermal reaction vessel containing a teflon liner may be used.
The temperature for the crystallization treatment may be 130 ℃ or higher and 170 ℃ or lower, and preferably may be 140 to 160 ℃; the time for the crystallization treatment may be 2 to 15 days, preferably 4 to 12 days.
Furthermore, the invention generally carries out post-treatment operations such as washing, drying and the like on the hydrothermal crystallization product. Specifically, for washing, washing to neutrality may be performed using water, and the drying may be performed at a temperature of 90 to 110 ℃.
Removing part of template agent
And removing less than 70 mass percent of template agent from the hydrothermal crystallization product to obtain an intermediate product, wherein the mass of the intermediate product is calculated by the total mass of the template agent. The invention firstly utilizes the chemical demoulding action to remove part of the template agent contained in the pre-synthesized molecular sieve, and then utilizes the metal particles (anions, such as PtCl) for the first time6 2-) With templating agents (cations, e.g. TEA) present in the structure of the molecular sieve+) And (3) encapsulating the metal nano particles into the molecular sieve structure under the electrostatic combination action.
For chemical demolding, specifically, the hydrothermal crystallization product may be subjected to acid washing treatment with an acid solution, so that a part of the template agent is removed from the hydrothermal crystallization product. The specific amount of template removed can be 10%, 20%, 30%, 40%, 45%, 50%, 55%, 60%, 65%, etc., based on the total mass of the template.
The acid solution is not particularly limited in the present invention, and may be any of those acidic solutions commonly used in the art. In some specific embodiments, the acid solution is an aqueous acetic acid solution in view of the effect of removal; more preferably, the mass fraction of acetic acid in the acetic acid aqueous solution is 20% to 80%, for example: 25%, 30%, 35%, 40%, 45%. 50%, 55%, 60%, 65%, 70%, 75%, etc.
The temperature and time of the acid washing treatment are not particularly limited in the present invention, as long as partial removal of the template agent can be achieved. Specifically, in the invention, the temperature of the acid washing treatment is 20-120 ℃; the time of the acid cleaning treatment is 4-24 h.
Similarly, the present invention generally applies to the intermediate product after-treatment operations such as washing, drying, etc. Specifically, for washing, washing may be performed to neutrality using water, the drying may be performed at a temperature of 50-70 ℃, and the drying time may be 8-16 hours.
Ion exchange
Furthermore, the intermediate product is subjected to ion exchange treatment by using a solution containing metal elements in active ingredients, the ion exchange can be carried out in the solution through corresponding charged ions in the template agent existing in the pore canal of the molecular sieve by metal ions, and the metal ions can be combined with the template agent through electrostatic action and are fixed inside the pore canal of the molecular sieve to form a packaging structure.
Specifically, the active ingredient is the active ingredient in the first aspect, and the salt solution of the active ingredient may be one or a combination of two or more of platinum salt, palladium salt, ruthenium salt, gold salt, and zinc salt.
For the solution containing the metal element in the active ingredient, it may be an acid solution or a salt solution. Specifically, the solution containing the metal element in the active ingredient may be a solution containing one or a combination of two or more of platinum, palladium, ruthenium, gold, and zinc. For example: the acid solution may be H2PtCl6、H2PdCl4、HAuCl4Etc.; the salt solution may be Na2PtCl6、Na2PdCl4、NaAuCl4、K2PtCl6、K2PdCl4、KAuCl4And the like.
As the solvent for forming the solution containing the metal element in the active ingredient, water may be generally used. The concentration of the solution containing the metal element in the active ingredient is not particularly limited as long as ion exchange can be achieved. Specifically, the concentration of the solution containing the metal element in the active ingredient is 0.1mol/L or less, for example, 0.001 to 0.06mol/L or the like.
Further, the conditions for carrying out the ion exchange in the present invention are not particularly limited as long as the ion exchange in the present invention can be achieved. In some specific embodiments, the temperature of the ion exchange treatment is 20 ℃ to 120 ℃, and the time of the ion exchange treatment is 2h to 24 h.
Similarly, the ion exchange product is usually subjected to post-treatment operations such as washing, drying, etc. Specifically, for the washing, the washing may be performed to be neutral using water, the drying may be performed at a temperature of 20 to 150 ℃, and the drying time may be 15 to 60 hours. For drying, the ion exchange product may be dried using a gradient temperature in order not to destroy its structure. For example: the drying can be carried out at the temperature of 20-40 ℃, then the drying is carried out at the temperature of 40-80 ℃, and then the drying is carried out at the temperature of 80-150 ℃, specifically, the drying time at the temperature of 20-40 ℃ is 5-20 h; drying at 40-80 deg.C for 5-20 hr; drying at 80-150 deg.C for 5-20 hr.
Roasting
And roasting the ion exchange product for one time to obtain the molecular sieve catalyst. The condition of the primary calcination is not particularly limited, and the calcination can be carried out at the temperature of 300-600 ℃ for 4-12 h to obtain the molecular sieve catalyst of the invention.
Further, the primary calcination is performed in an oxygen-containing atmosphere and/or a hydrogen-containing atmosphere. Preferably, the reaction may be carried out in an oxygen-containing atmosphere and then in a hydrogen-containing atmosphere. As the oxygen-containing atmosphere, an air atmosphere or the like may be mentioned.
Further, after primary roasting, ammonium exchange treatment can be carried out on the ion exchange product, wherein the ammonium exchange is that cations for balancing the charges of the molecular sieve framework are changed into ammonium ions through ion exchange, and then the ammonium ions are changed into a hydroxyl structure through high-temperature treatment, and the hydroxyl on the surface of the molecular sieve can be in synergistic action with packaging metal to provide an acid site for related catalytic reaction. Specifically, the ammonium salt exchange treatment may be performed in an ammonium salt solution, and the ammonium salt solution is not particularly limited in the present invention, and may be an ammonium salt solution commonly used in the art, for example: NH (NH)4Cl, and the like. As for the conditions of the ammonium exchange treatment, the temperature of the ammonium exchange treatment is 70 to 90 ℃ and the time of the ammonium exchange treatment is 2 to 4 hours.
After the ammonium exchange treatment, the second calcination may be further performed. The conditions for the second calcination are not particularly limited, and the second calcination may be the same as the calcination conditions, specifically, the second calcination may be carried out at a temperature of 300 ℃ to 600 ℃ for 4 hours to 12 hours to obtain the molecular sieve catalyst of the present invention. The secondary roasting is carried out in oxygen-containing atmosphere and/or hydrogen-containing atmosphere. Preferably, the reaction may be carried out in an oxygen-containing atmosphere and then in a hydrogen-containing atmosphere. As the oxygen-containing atmosphere, an air atmosphere or the like is possible, so that a metal oxide-containing molecular sieve catalyst can be obtained.
In addition, the molecular sieve catalyst containing the metal oxide can be reduced under the hydrogen atmosphere, so that the molecular sieve catalyst containing the metal particles can be obtained; wherein the reduction temperature is 300-700 ℃, and the reduction time can be 0.1-5 h.
The preparation method of the invention synthesizes the BEA structure molecular sieve by using the template agent and a hydrothermal crystallization method, then removes part of the template agent by chemical demoulding action for the first time, and uses metal particles (anions, such as PtCl) for the first time on the basis of the template agent6 2-) With templating agents (cations, e.g. TEA) present in the structure of the molecular sieve+) Under the electrostatic combination action, the metal nano particles are encapsulated into the molecular sieve structure, and then the nano metal particles are converted into metal oxide encapsulation while the template agent is removed by bakingAnd finally, reducing the metal from a fixed position in a hydrogen atmosphere inside the molecular sieve structure. The preparation method can avoid the aggregation of metal nano particles, so that the metal particles are uniform in size, uniform in dispersion and certain in lattice regularity, and the molecular sieve catalyst with the BEA structure for encapsulating metal and/or metal oxide is obtained.
Third aspect of the invention
A third aspect of the invention provides a use of the molecular sieve catalyst according to the first aspect of the invention or the molecular sieve catalyst prepared by the preparation method of the second aspect of the invention in catalytic hydrogenation, catalytic deoxygenation, catalytic oxidation or catalytic dehydrogenation reactions.
Specifically, the molecular sieve catalyst with the BEA structure encapsulating the active ingredient can catalyze the hydroisomerization reaction of organic compounds such as toluene and the like to carbon dioxide and water, the hydroisomerization reaction of organic compounds such as n-heptane and the like, the reaction of synthesizing hydrogen peroxide from hydrogen and oxygen, the hydrocracking reaction of organic compounds such as n-decane and the like, and the hydrodeoxygenation reaction of guaiacol and the like.
Examples
Embodiments of the present invention will be described in detail below with reference to examples, but those skilled in the art will appreciate that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products commercially available.
The template agent used in the invention is tetraethylammonium hydroxide (TEAOH), the silicon source used is tetraethyl orthosilicate (TEOS), the aluminum source used is sodium metaaluminate (NaAlO)2) For example, the water used is deionized water, and the reagents used are all analytical reagents; the high power transmission microscope test of the obtained finished product is carried out by using JEM-2100, the accelerating voltage is 200KV, the content of metal in the obtained finished product is determined by an element analyzer ICP-9000(N + M), and the X-ray diffraction analysis test of the obtained finished product is determined by adopting a Bruker D8-Focus X-ray diffractometerAnd (4) determining.
[ examples 1 to 5 ]
0.164g of sodium metaaluminate (NaAlO)2) 20.833g of tetraethyl orthosilicate (TEOS), 32.539g of tetraethylammonium hydroxide (25 wt% aqueous solution) and 29.452g of deionized water to prepare a mixed solution, stirring the mixed solution at room temperature for 24 hours to obtain a crystallization solution, placing the crystallization solution in a crystallization kettle, and performing hydrothermal crystallization at 140 ℃ for 10 days to obtain a hydrothermal crystallization product; washing the synthesized hydrothermal crystallization product powder to be neutral by using deionized water, and drying at the temperature of 100 ℃ to obtain the beta molecular sieve precursor containing the template agent in the molecular sieve structure for later use.
Weighing 1g of the prepared beta molecular sieve precursor containing the template agent, adding the beta molecular sieve precursor into 500mL of acetic acid aqueous solution with the mass fraction of 50%, stirring the mixture at 80 ℃ for 12 hours, and filtering the mixture after the stirring to obtain an intermediate product. Washing the template solution to be neutral by using deionized water, and drying the template solution for 12 hours at the temperature of 60 ℃ to obtain the beta-type molecular sieve catalyst precursor with a part of the template agent removed, wherein 65 percent of the template agent is removed based on the total mass of the template agent.
Weighing appropriate amount of H2PtCl6·6H2Dissolving O in deionized water to prepare a Pt solution with the concentration of 0.001-0.1 mol/L, weighing 1g of the prepared beta-type molecular sieve catalyst precursor with partial demolding, adding the beta-type molecular sieve catalyst precursor into 80g of Pt-containing aqueous solution, and stirring for 4 hours at 50 ℃ to perform ion exchange. After separation, the catalyst is washed for 3 times by deionized water, dried for 12 hours at 30 ℃, dried for 12 hours at 60 ℃ and dried for 12 hours at 120 ℃ in sequence, and roasted for 6 hours at 500 ℃ in air atmosphere to obtain the beta-structure molecular sieve catalyst containing Pt oxide nanoparticles.
Weighing 1g of beta-structure molecular sieve catalyst containing Pd oxide nanoparticles after roasting, and adding 100mL of 1mol/LNH4Stirring the solution in Cl solution at 85 ℃ for 3 hours to perform ammonium exchange treatment, washing the solution by using deionized water after the ammonium exchange treatment is finished, drying the solution at 100 ℃ for 24 hours, roasting the solution at 550 ℃ for 4 hours, and repeating the steps for 3 times; and then roasting for 6 hours in the air atmosphere at 550 ℃ in the air atmosphere to obtain the beta-structure molecular sieve catalyst for packaging Pt oxide nanoparticles.
H used in example 12PtCl6Adding 0g of NaOH into the mixed solution with the solution concentration of 0.001 mol/L; the content of Pt oxide was 0.26% by mass of the total mass of the beta-structured molecular sieve catalyst encapsulating the Pt oxide nanoparticles.
H used in example 22PtCl6Adding 0.122g NaOH into the mixed solution with the solution concentration of 0.004 mol/L; the content of Pt oxide was 0.47% by mass of the total mass of the beta-structured molecular sieve catalyst encapsulating the Pt oxide nanoparticles.
H used in example 32PtCl6Adding 0.244g NaOH into the mixed solution with the solution concentration of 0.006 mol/L; the content of Pt oxide was 1.03% based on the total mass of the beta-structured molecular sieve catalyst encapsulating the Pt oxide nanoparticles.
H used in example 42PtCl6The solution concentration is 0.008mol/L, and 0g of KOH is added into the mixed solution; the content of Pt oxide was 1.51% by mass of the total mass of the beta-structured molecular sieve catalyst encapsulating the Pt oxide nanoparticles.
H used in example 52PtCl6The solution concentration is 0.016mol/L, and 0.236g KOH is added into the mixed solution; the content of Pt oxide was 2.35% by mass of the total mass of the beta-structured molecular sieve catalyst encapsulating the Pt oxide nanoparticles.
A TEM image of the catalyst prepared in example 1 is shown in fig. 1, and it can be seen that Pt oxides are highly and uniformly dispersed in the beta molecular sieve, the average particle size of the metal oxide obtained by statistics is 0.82nm, and the particle size of the beta molecular sieve carrier is 200 nm; the specific surface area of the molecular sieve catalyst is 353m2Per g, pore volume 0.654cm3/g。
[ examples 6 to 10 ] to provide a toner
0.164g of sodium metaaluminate (NaAlO)2) 20.833g of tetraethyl orthosilicate (TEOS), 32.539g of tetraethylammonium hydroxide (25 wt% aqueous solution) and 29.452g of deionized water to prepare a mixed solution, stirring the mixed solution at room temperature for 24 hours to obtain a crystallization solution, placing the crystallization solution in a crystallization kettle, and carrying out hydrothermal crystallization at 140 ℃ for 10 days to obtain a hydrothermal crystallization product; the synthesized hydrothermal crystallization product powder is usedWashing the product to neutrality with ionized water, and drying at 100 deg.c to obtain beta molecular sieve precursor containing template agent.
Weighing 1g of the prepared beta molecular sieve precursor containing the template agent, adding the beta molecular sieve precursor into 500mL of acetic acid aqueous solution with the mass fraction of 50%, stirring the mixture at 80 ℃ for 12 hours, and filtering the mixture after the stirring to obtain an intermediate product. Washing the template solution to be neutral by using deionized water, and drying the template solution for 12 hours at the temperature of 60 ℃ to obtain the beta-type molecular sieve catalyst precursor without part of the template agent, wherein 65 percent of the template agent is removed based on the total mass of the template agent.
Weighing appropriate amount of Na2PdCl4Dissolving the catalyst in deionized water to prepare a Pd solution with the concentration of 0.001-0.1 mol/L, weighing 1g of the prepared beta-type molecular sieve catalyst precursor with partial demolding, adding the beta-type molecular sieve catalyst precursor into 80g of Pd-containing aqueous solution, and stirring the mixture for 4 hours at 50 ℃ to perform ion exchange. After separation, the catalyst is washed for 3 times by deionized water, dried for 12 hours at 30 ℃, dried for 12 hours at 60 ℃ and dried for 12 hours at 120 ℃ in sequence, and roasted for 6 hours at 500 ℃ in air atmosphere to obtain the beta-structure molecular sieve catalyst containing Pd oxide nanoparticles.
Weighing 1g of calcined beta-structure molecular sieve catalyst containing Pd oxide nanoparticles, and adding 100mL of 1mol/LNH4Stirring the solution in Cl solution at 85 ℃ for 3 hours to perform ammonium exchange treatment, washing the solution by using deionized water after the ammonium exchange treatment is finished, drying the solution at 100 ℃ for 12 hours, roasting the solution at 550 ℃ for 4 hours, and repeating the steps for 3 times; and then roasting for 6 hours in the air atmosphere at 550 ℃ in the air atmosphere to obtain the beta-structure molecular sieve catalyst for packaging the Pd oxide nanoparticles.
Na used in example 62PdCl4The concentration of the solution is 0.001 mol/L; the content of the Pd oxide is 0.23 percent based on the total mass of the beta-structure molecular sieve catalyst for encapsulating the Pd oxide nano particles.
Na used in example 72PdCl4The concentration of the solution is 0.004 mol/L; the content of the Pd oxide is 0.43 percent based on the total mass of the beta-structure molecular sieve catalyst for encapsulating the Pd oxide nano particles.
Na used in example 82PdCl4The concentration of the solution is 0.008 mol/L; the content of Pd oxide was 1.36% based on the total mass of the beta-structured molecular sieve catalyst encapsulating the Pd oxide nanoparticles.
Na used in example 92PdCl4The concentration of the solution is 0.012 mol/L; the content of the Pd oxide was 2.54% based on the total mass of the beta-structured molecular sieve catalyst encapsulating the Pd oxide nanoparticles.
Na used in example 102PdCl4The concentration of the solution is 0.016 mol/L. The content of the Pd oxide is 2.98 percent of the total mass of the beta-structure molecular sieve catalyst for encapsulating the Pd oxide nano particles.
A TEM image of the catalyst prepared in example 8 is shown in fig. 2, and it can be seen that the metal Pd oxide is highly uniformly dispersed in the beta molecular sieve, and the statistical average particle size of the metal oxide is 1.33nm, and the average particle size of the beta molecular sieve support is 350 nm; the specific surface area of the molecular sieve catalyst is 367m2Per g, pore volume 0.523cm3/g。
[ examples 11 to 15 ]
0.164g of sodium metaaluminate (NaAlO)2) 20.833g of tetraethyl orthosilicate (TEOS), 32.539g of tetraethylammonium hydroxide (25 wt% aqueous solution) and 29.452g of deionized water to prepare a mixed solution, stirring the mixed solution at room temperature for 24 hours to obtain a crystallization solution, placing the crystallization solution in a crystallization kettle, and carrying out hydrothermal crystallization at 140 ℃ for 10 days to obtain a hydrothermal crystallization product; washing the synthesized hydrothermal crystallization product powder to be neutral by using deionized water, and drying at the temperature of 100 ℃ to obtain the beta molecular sieve precursor containing the template agent in the molecular sieve structure for later use.
Weighing 1g of the prepared beta molecular sieve precursor containing the template agent, adding the beta molecular sieve precursor into 500mL of acetic acid aqueous solution with the mass fraction of 50%, stirring the mixture at 80 ℃ for 12 hours, and filtering the mixture after the stirring to obtain an intermediate product. Washing the template solution to be neutral by using deionized water, and drying the template solution for 12 hours at the temperature of 60 ℃ to obtain the beta-type molecular sieve catalyst precursor with a part of template agent removed, wherein 65% of the template agent is removed based on the total mass of the template agent.
Weighing appropriate amount of HAuCl4Dissolve inPreparing an Au solution with the concentration of 0.001-0.1 mol/L in the ionized water, weighing 1g of the prepared beta-type molecular sieve catalyst precursor with a part of demolding, adding the beta-type molecular sieve catalyst precursor into 80g of Au-containing aqueous solution, and stirring for 4 hours at 50 ℃ to perform ion exchange. After separation, the catalyst is washed for 3 times by deionized water, dried for 12 hours at 30 ℃, dried for 12 hours at 60 ℃ and dried for 12 hours at 120 ℃ in sequence, and roasted for 6 hours at 500 ℃ in air atmosphere to obtain the beta-structure molecular sieve catalyst containing Au oxide nanoparticles.
Weighing 1g of beta-structure molecular sieve catalyst containing Au oxide nanoparticles after roasting, and adding 100mL of 1mol/LNH4Stirring the solution in Cl solution for 3 hours at 85 ℃ to perform ammonium exchange treatment, washing the solution by using deionized water after the ammonium exchange treatment is finished, drying the solution for 124 hours at 100 ℃, roasting the solution for 4 hours at 550 ℃, and repeating the steps for 3 times; and then roasting for 6 hours in the air atmosphere at 550 ℃ in the air atmosphere to obtain the beta-structure molecular sieve catalyst for packaging the Au oxide nanoparticles.
HAuCl used in example 114The concentration of the solution is 0.001 mol/L; the content of Au oxide was 0.33% based on the total mass of the molecular sieve catalyst of β structure encapsulating Au oxide nanoparticles.
HAuCl used in example 124The concentration of the solution is 0.004 mol/L; the content of Au oxide was 0.64% based on the total mass of the molecular sieve catalyst of β structure encapsulating Au oxide nanoparticles.
HAuCl used in example 134The concentration of the solution is 0.008 mol/L; the content of Au oxide was 1.47% based on the total mass of the molecular sieve catalyst of β structure encapsulating Au oxide nanoparticles.
HAuCl used in example 144The concentration of the solution is 0.012 mol/L; the content of Au oxide was 2.87% by total mass of the molecular sieve catalyst of β structure encapsulating Au oxide nanoparticles.
HAuCl used in example 154The concentration of the solution is 0.016 mol/L; the content of Au oxide was 3.15% based on the total mass of the molecular sieve catalyst of β structure encapsulating Au oxide nanoparticles.
TEM catalyst prepared in example 12As shown in fig. 3, it can be seen that the metal Pd is highly uniformly dispersed in the beta molecular sieve, and the average particle size of the metal oxide obtained by statistics is 1.3 nm. The average particle size of the beta molecular sieve carrier is 407 nm; the specific surface area of the molecular sieve catalyst is 395m2Per g, pore volume 0.513cm3/g。
A TEM image of the catalyst prepared in example 15 is shown in fig. 4, which shows that the metal Pd is highly uniformly dispersed in the beta molecular sieve, and the statistical average particle size of the metal oxide is 1.01nm, and the average particle size of the beta molecular sieve support is 420 nm; the specific surface area of the molecular sieve catalyst is 387m2Per g, pore volume 0.492cm3/g。
[ examples 16 to 19 ] of the present invention
0.164g of sodium metaaluminate (NaAlO)2) 20.833g of tetraethyl orthosilicate (TEOS), 32.539g of tetraethylammonium hydroxide (25 wt% aqueous solution) and 29.452g of deionized water to prepare a mixed solution, stirring the mixed solution at room temperature for 24 hours to obtain a crystallization solution, placing the crystallization solution in a crystallization kettle, and carrying out hydrothermal crystallization at 140 ℃ for 10 days to obtain a hydrothermal crystallization product; washing the synthesized hydrothermal crystallization product powder to be neutral by using deionized water, and drying at the temperature of 100 ℃ to obtain the beta molecular sieve precursor containing the template agent in the molecular sieve structure for later use.
Weighing 1g of the prepared beta molecular sieve precursor containing the template agent, adding the beta molecular sieve precursor into 500mL of acetic acid aqueous solution, stirring for a certain time at 80 ℃, and filtering after the stirring to obtain an intermediate product. Washing the product to be neutral by using deionized water, and drying the product for 12 hours at the temperature of 60 ℃ to obtain the beta-type molecular sieve catalyst precursor with a part of template agent removed.
Weighing appropriate amount of H2PtCl6·6H2Dissolving O in deionized water to prepare a Pt solution with the concentration of 0.005mol/L, weighing 1g of the prepared beta-type molecular sieve catalyst precursor with partial demolding, adding the beta-type molecular sieve catalyst precursor into 80g of water solution containing Pt, and stirring for 4 hours at 50 ℃ to perform ion exchange. After separation, the mixture is washed for 3 times by deionized water, dried for 12 hours at 30 ℃, dried for 12 hours at 60 ℃ and dried for 12 hours at 120 ℃ in sequence, and roasted for 6 hours at 500 ℃ in air atmosphere to prepare the beta structure containing Pt oxide nanoparticlesA molecular sieve catalyst.
Weighing 1g of calcined beta-structure molecular sieve catalyst containing Pt oxide nanoparticles, and adding 100mL of 1mol/LNH4Stirring the solution in Cl solution at 85 ℃ for 3 hours to perform ammonium exchange treatment, washing the solution by using deionized water after the ammonium exchange treatment is finished, drying the solution at 100 ℃ for 24 hours, roasting the solution at 550 ℃ for 4 hours, and repeating the steps for 3 times; then roasting for 6 hours in the air atmosphere at 550 ℃; and then reducing the mixture for 2 hours at a constant temperature of 500 ℃ in a hydrogen atmosphere to obtain the beta-structure molecular sieve catalyst for packaging Pt nano particles.
The mass fraction of the acetic acid aqueous solution used in example 16 was 40%, and the stirring time was 12 hours, wherein 45% of the templating agent was removed based on the total mass of the templating agent; the content of Pt was 0.44% by mass of the total mass of the molecular sieve catalyst of β structure encapsulating the Pt nanoparticles.
The mass fraction of the acetic acid aqueous solution used in example 17 was 50%, and the stirring time was 8 hours, wherein 53% of the template agent was removed based on the total mass of the template agent; the content of Pt was 0.47% by mass of the total mass of the molecular sieve catalyst of β structure encapsulating the Pt nanoparticles.
The mass fraction of the acetic acid aqueous solution used in example 18 was 60%, and the stirring time was 8 hours, wherein 62% of the templating agent was removed based on the total mass of the templating agent; the content of Pt was 0.49% by mass of the total mass of the molecular sieve catalyst of β structure encapsulating the Pt nanoparticles.
The mass fraction of the acetic acid aqueous solution used in example 19 was 70%, and the stirring time was 6 hours, wherein 55% of the templating agent was removed, based on the total mass of the templating agent; the content of Pt was 0.51% by mass of the total mass of the molecular sieve catalyst of β structure encapsulating the Pt nanoparticles.
The XRD patterns of the catalysts prepared in example 16, example 17 and example 18 are shown in fig. 5A, 5B and 5C, respectively, and the comparison of 47-0183 in PDF card of standard XRD (Jade 6) shows that the prepared molecular sieves are typical BEA crystal phases, and different acid concentrations and acid treatment times do not affect the framework crystal form of the molecular sieves.
Catalyst prepared in example 16A TEM image is shown in fig. 6, which shows that the metal Pt is highly uniformly dispersed in the beta molecular sieve, and the average particle size of the metal oxide obtained by statistics is 1.75nm, and the average particle size of the beta molecular sieve support is 480 nm; the specific surface area of the molecular sieve catalyst is 691m2Per g, pore volume 0.528cm3/g。
[ examples 20 to 25 ]
Weighing appropriate amount of sodium metaaluminate (NaAlO)2) 20.833g of tetraethyl orthosilicate (TEOS), a proper amount of tetraethylammonium hydroxide (25 wt% aqueous solution) and a proper amount of deionized water to prepare a mixed solution, stirring the mixed solution at room temperature for 24 hours to obtain a crystallization solution, placing the crystallization solution in a crystallization kettle, and carrying out hydrothermal crystallization at 140 ℃ for 10 days to obtain a hydrothermal crystallization product; washing the synthesized hydrothermal crystallization product powder to be neutral by using deionized water, and drying at the temperature of 100 ℃ to obtain a molecular sieve precursor containing the template agent beta molecular sieve in the molecular sieve structure for later use.
Weighing 1g of the prepared beta molecular sieve precursor containing the template agent, adding 500mL of acetic acid aqueous solution with the mass concentration of 50 wt%, stirring at 80 ℃ for 12h, and filtering after the stirring to obtain an intermediate product. Washing the template solution to be neutral by using deionized water, and drying the template solution for 12 hours at the temperature of 60 ℃ to obtain the beta-type molecular sieve catalyst precursor with a part of template agent removed, wherein 65% of the template agent is removed based on the total mass of the template agent.
Weighing appropriate amount of H2PtCl6·6H2Dissolving O in deionized water to prepare a Pt solution with the concentration of 0.005mol/L, weighing 1g of the prepared beta-type molecular sieve catalyst precursor with partial demolding, adding the beta-type molecular sieve catalyst precursor into 80g of water solution containing Pt with the concentration of 0.005mol/L, and stirring for 4 hours at 50 ℃ to perform ion exchange. And after separation, washing the catalyst for 3 times by using deionized water, drying the catalyst for 12 hours at 30 ℃, drying the catalyst for 12 hours at 60 ℃ and drying the catalyst for 12 hours at 120 ℃ in sequence, and roasting the catalyst for 6 hours at 500 ℃ in an air atmosphere to prepare the beta-structure molecular sieve catalyst containing Pt oxide nanoparticles.
Weighing 1g of calcined beta-structure molecular sieve catalyst containing Pt oxide nanoparticles, and adding 100mL of 1mol/LNH4Stirring the solution in Cl solution for 3 hours at the temperature of 85 ℃ to perform ammonium exchange treatment, and obtainingWashing with deionized water, drying at 100 deg.C for 24 hr, calcining at 550 deg.C for 4 hr, and repeating the above steps for 3 times; then roasting for 6 hours in the air atmosphere at 550 ℃; and then reducing the mixture for 2 hours at a constant temperature of 500 ℃ in a hydrogen atmosphere to obtain the beta-structure molecular sieve catalyst for packaging Pt nano particles.
In example 20, 0.082g of sodium metaaluminate (NaAlO) was used2)32.539g of tetraethylammonium hydroxide (25 wt% aqueous solution) and 29.452g of deionized water; the content of Pt was 0.48% by total mass of the molecular sieve catalyst of β structure encapsulating the Pt nanoparticles.
In example 21, 0.041g of sodium metaaluminate (NaAlO) was used2) Tetraethylammonium hydroxide (25 wt% aqueous solution) 16.270, deionized water 14.726 g; the content of P was 0.52% by mass of the total mass of the molecular sieve catalyst of β structure encapsulating the Pt nanoparticles.
Example 22 use 0.164g of sodium metaaluminate (NaAlO)2)32.539g of tetraethylammonium hydroxide (25 wt% aqueous solution) and 29.452g of deionized water; the content of Pt was 0.55% by mass of the total mass of the molecular sieve catalyst of β structure encapsulating the Pt nanoparticles.
In example 23, 0.328g of sodium metaaluminate (NaAlO)2)48.677g of tetraethylammonium hydroxide (25 wt% aqueous solution) and 44.188g of deionized water; the content of Pt was 0.44% by mass of the total mass of the molecular sieve catalyst of β structure encapsulating the Pt nanoparticles.
In example 24, 0.041g of sodium metaaluminate (NaAlO) was used2)32.539g of tetraethylammonium hydroxide (25 wt% aqueous solution) and 29.452g of deionized water; the content of Pt was 0.47% by mass of the total mass of the molecular sieve catalyst of β structure encapsulating the Pt nanoparticles.
In example 25, 0.164g of sodium metaaluminate (NaAlO) was used2)40.126g of tetraethylammonium hydroxide (25 wt% aqueous solution) and 18.267g of deionized water; the content of Pt was 0.47% by mass of the total mass of the molecular sieve catalyst of β structure encapsulating the Pt nanoparticles.
In example 21 and example 22, XRD patterns of the prepared catalysts are shown in fig. 7A and 7B, respectively, and according to the comparison of standard XRD (Jade 6) PDF cards 47-0183, the prepared molecular sieves are all typical BEA crystal phases, and different ratios of raw materials do not affect the crystal structure of the molecular sieve framework.
A TEM image of the catalyst prepared in example 23 is shown in fig. 8, which shows that the metal Pt is highly uniformly dispersed in the beta molecular sieve, and the statistical average particle size of the metal oxide is 1.37nm and the average particle size of the beta molecular sieve support is 430 nm; the specific surface area of the molecular sieve catalyst is 386m2Per g, pore volume 0.621cm3/g。
[ example 26 ]
The catalyst obtained in the embodiment 4 is used for catalyzing the reaction of complete oxidation of toluene, and specifically comprises the following steps of placing 0.25g of the catalyst in a fixed bed reaction tube, heating to 100 ℃, pumping toluene to gasify the toluene, wherein the concentration of the toluene is 1000ppm, continuing to perform temperature programming, heating at a rate of 5 ℃/min, introducing oxygen at a gas flow rate of 100mL/min to perform reaction, condensing and collecting the obtained product to be completely carbon dioxide and water, and enabling the conversion rate of the toluene to reach 100%; in contrast, the conversion of toluene in the conventional catalyst prepared by the conventional impregnation method was only 70% under the same conditions, as shown in fig. 9.
The preparation method of the direct loading type metal Pt catalyst comprises the following steps: 0.164g of sodium metaaluminate (NaAlO)2) 20.833g of tetraethyl orthosilicate (TEOS), 32.539g of tetraethylammonium hydroxide (25 wt% aqueous solution) and 29.452g of deionized water to prepare a mixed solution, stirring the mixed solution at room temperature for 24 hours to obtain a crystallization solution, placing the crystallization solution in a crystallization kettle, and carrying out hydrothermal crystallization at 140 ℃ for 10 days to obtain a hydrothermal crystallization product; washing the synthesized hydrothermal crystallization product powder to be neutral by using deionized water, drying at the temperature of 100 ℃, and roasting at the temperature of 550 ℃ for 6 hours to obtain a beta molecular sieve for later use;
weighing appropriate amount of H2PtCl6·6H2Dissolving O in deionized water to obtain Pt solution with concentration of 0.013mol/L, soaking 1g of beta molecular sieve in 5g of Pt solution, directly loading metal on the molecular sieve, drying at 30 deg.C for 12 hr, at 60 deg.C for 12 hr and at 120 deg.C for 12 hr, and calcining at 500 deg.C in air atmosphere for 6 hr to obtain Pt-containing oxideA nanoparticle beta structure molecular sieve catalyst.
Weighing 1g of beta-structure molecular sieve catalyst containing Pt oxide nanoparticles after roasting, and adding 100mL of 1mol/LNH4Stirring the solution in Cl solution for 3 hours at 85 ℃ to perform ammonium exchange treatment, washing the solution by using deionized water after the ammonium exchange treatment is finished, drying the solution for 24 hours at 60-140 ℃, roasting the solution for 4 hours at 550 ℃, and repeating the steps for 3 times; and then roasting the catalyst in the air atmosphere at 550 ℃ for 6 hours to obtain the conventional catalyst prepared by the common impregnation method, wherein the content of the Pt oxide is 1.51 percent based on the total mass of the conventional catalyst.
[ example 27 ]
The catalyst obtained in the embodiment 5 is used for catalyzing the hydroisomerization reaction of n-heptane, and specifically comprises the following steps of placing 0.5g of the catalyst in a fixed bed reaction tube, heating to 500 ℃ for reduction, then cooling to 300 ℃, pumping in 0.1mL/min n-heptane and introducing hydrogen for reaction, and analyzing the obtained product on line by using gas chromatography, wherein the isomerization conversion rate of n-heptane reaches more than 80%; while the isomerization conversion of n-heptane using the existing directly supported metal Pt catalyst was only 36% under the same conditions, as shown in fig. 10.
The preparation method of the direct loading type metal Pt catalyst comprises the following steps: the difference from example 26 is that the concentration of the Pt solution was 0.021mol/L, and the content of Pt oxide was 2.35% based on the total mass of the existing catalyst.
[ example 28 ]
The catalyst obtained in the example 7 is used for catalyzing the reaction of synthesizing hydrogen peroxide from hydrogen and oxygen, and specifically comprises the following steps of adding 0.1g of the catalyst into 60mL of methanol solution, transferring the methanol solution into a reaction kettle, and adopting high-purity N2Continuously purging the reaction kettle for 5min to remove air in the reaction kettle, and introducing H into the reaction kettle2/O2/N2(4/8/20mL/min), until the pressure of the reaction kettle reaches 1.0MPa, the reaction feed is closed; setting the stirring speed at 800rpm, starting stirring timing after the temperature of the reaction kettle is stabilized to 30 ℃, and measuring the concentration of hydrogen peroxide in the solution after reaction to evaluate the catalytic activity of the catalyst. As shown in FIG. 11, using example 7 gaveThe yield of hydrogen peroxide in the solution can reach more than 50 percent after the beta molecular sieve is subjected to encapsulation reaction for 80min, and the yield of the hydrogen peroxide is only less than 30 percent by using a molecular sieve direct impregnation method to load Pd, so that the catalytic activity is obviously improved.
The preparation method of the direct loading type contrast catalyst comprises the following steps: 0.164g of sodium metaaluminate (NaAlO)2) 20.833g of tetraethyl orthosilicate (TEOS), 32.539g of tetraethylammonium hydroxide (25 wt% aqueous solution) and 29.452g of deionized water to obtain a mixed solution, stirring the mixed solution at room temperature for 24 hours to obtain a crystallization solution, placing the crystallization solution in a crystallization kettle, and carrying out hydrothermal crystallization at 140 ℃ for 10 days to obtain a hydrothermal crystallization product. Washing the synthesized hydrothermal crystallization product powder to be neutral by using deionized water, and roasting for 6 hours at the temperature of 550 ℃ after drying at the temperature of 100 ℃ to obtain the beta molecular sieve for later use.
Weighing appropriate amount of Na2PdCl4Dissolving in deionized water to prepare a Pd solution with the concentration of 0.007mol/L, adopting an impregnation method, namely immersing 1g of beta molecular sieve in 5g of the Pd solution, directly loading metal on the molecular sieve, drying the metal on the molecular sieve for 12 hours at 30 ℃, drying the metal on the molecular sieve for 12 hours at 60 ℃ and drying the metal on the molecular sieve for 12 hours at 120 ℃, and roasting the metal on the molecular sieve for 6 hours at 500 ℃ in an air atmosphere to prepare the beta-structure molecular sieve catalyst containing Pt oxide nanoparticles.
Weighing 1g of beta-structure molecular sieve catalyst containing Pt oxide nanoparticles after roasting, and adding 100mL of 1mol/LNH4Stirring the solution in Cl solution for 3 hours at 85 ℃ to perform ammonium exchange treatment, washing the solution by using deionized water after the ammonium exchange treatment is finished, drying the solution for 24 hours at 60-140 ℃, roasting the solution for 4 hours at 550 ℃, and repeating the steps for 3 times; then roasting the catalyst in the air atmosphere at 550 ℃ for 6 hours to obtain the existing catalyst prepared by the common impregnation method, wherein the content of Pd oxide is 0.43 percent based on the total mass of the existing catalyst.
[ example 29 ]
The catalyst obtained in the example 14 is used for catalyzing the reaction of hydrocracking of n-decane, and specifically comprises the following steps of placing 0.5g of the catalyst in a fixed bed reaction tube, and heating to 500 ℃ for reduction in a hydrogen atmosphere; then, the temperature is reduced to 350 ℃, n-decane is pumped in for 0.2mL/min, hydrogen is introduced at the gas flow rate of 50mL/min, the cracked product is detected by gas chromatography, and the cracking conversion rate of the catalyst n-decane obtained in the embodiment 14 reaches more than 70 percent; while the conversion of toluene was only 45% under the same conditions using the direct supported control catalyst, as shown in fig. 12.
The preparation method of the direct loading type contrast catalyst comprises the following steps: 0.164g of sodium metaaluminate (NaAlO)2) 20.833g of tetraethyl orthosilicate (TEOS), 32.539g of tetraethylammonium hydroxide (25 wt% aqueous solution) and 29.452g of deionized water to prepare a mixed solution, stirring the mixed solution at room temperature for 24 hours to obtain a crystallization solution, placing the crystallization solution in a crystallization kettle, and carrying out hydrothermal crystallization at 140 ℃ for 10 days to obtain a hydrothermal crystallization product; washing the synthesized hydrothermal crystallization product powder to be neutral by using deionized water, and roasting for 6 hours at the temperature of 550 ℃ after drying at the temperature of 100 ℃ to obtain the beta molecular sieve for later use.
Weighing appropriate amount of HAuCl4Dissolving in deionized water to prepare an Au solution with the concentration of 0.013mol/L, adopting a dipping method, namely immersing 1g of beta molecular sieve in 5g of Au solution, directly loading metal on the molecular sieve, drying the metal on the molecular sieve for 12 hours at 30 ℃, drying the metal on the molecular sieve for 12 hours at 60 ℃ and drying the metal on the molecular sieve for 12 hours at 120 ℃, and roasting the metal on the molecular sieve for 6 hours at 500 ℃ in an air atmosphere to prepare the beta-structure molecular sieve catalyst containing Au oxide nanoparticles.
Weighing 1g of beta-structure molecular sieve catalyst containing Pt oxide nanoparticles after roasting, and adding 100mL of 1mol/LNH4Stirring the solution in Cl solution for 3 hours at 85 ℃ to perform ammonium exchange treatment, washing the solution by using deionized water after the ammonium exchange treatment is finished, drying the solution for 24 hours at 60-140 ℃, roasting the solution for 4 hours at 550 ℃, and repeating the steps for 3 times; and then roasting the catalyst in an air atmosphere at 550 ℃ for 6 hours to obtain the existing catalyst, wherein the content of the Au oxide is 2.87 percent based on the total mass of the existing catalyst.
[ example 30 ]
The catalyst obtained in the embodiment 3 is used for the reaction of the guaiacol hydrodeoxygenation, and specifically comprises the following steps of reducing 0.2g of the catalyst for 2 hours at 500 ℃ in a hydrogen atmosphere, then adding 0.2g of guaiacol into 40mL of n-decane, placing the mixture in a batch reactor, heating to 380 ℃, stirring for reaction for 6 hours, cooling to room temperature, detecting a cracking product by using a gas chromatography, wherein the conversion rate of the guaiacol catalyst obtained in the embodiment 3 is more than 60%; however, the conversion of guaiacol in the existing catalyst prepared by direct impregnation method was only 40% under the same conditions, as shown in fig. 13.
The preparation method of the existing catalyst prepared by the direct impregnation method comprises the following steps: the difference from example 26 is that the concentration of the Pt solution was 0.009mol/L and the content of Pt oxide was 1.03% based on the total mass of the existing catalyst.
Industrial applicability
The molecular sieve catalyst provided by the invention can be industrially prepared and can be applied to catalytic hydrodeoxygenation.
The above examples of the present invention are merely examples for clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims (10)

1. A molecular sieve catalyst, comprising:
a molecular sieve support having an average particle size of 50-500nm, the molecular sieve support having a BEA structure; and
the active ingredient is metal and/or metal oxide, and the average particle size of the active ingredient is 0.5-4 nm; wherein
At least 95% or more of the active ingredient, based on the total mass of the active ingredient, is located inside the molecular sieve support.
2. The molecular sieve catalyst according to claim 1, characterized in that the active ingredient is present in an amount of 0.01 to 5% by mass, based on the total mass of the molecular sieve catalyst.
3. The molecular sieve catalyst according to claim 1 or 2, wherein the metal element in the active component is one or a combination of two or more of platinum, palladium, ruthenium, gold, and zinc.
4. The molecular sieve catalyst according to any of claims 1 to 3, characterized in that the molecular sieve catalyst has a specific surface area of 250-700m2Per g, pore volume of 0.4-0.8cm3/g。
5. A method of preparing a molecular sieve catalyst according to any of claims 1 to 4, comprising the steps of:
mixing a silicon source, a template agent, an optional alkali source and an optional aluminum source in a solvent to obtain a precursor solution;
carrying out hydrothermal crystallization treatment on the precursor solution to obtain a hydrothermal crystallization product;
removing less than 70 mass percent of template agent from the hydrothermal crystallization product to obtain an intermediate product, wherein the intermediate product is calculated by the total mass of the template agent;
and (3) carrying out ion exchange treatment on the intermediate product by using a solution containing metal elements in the active components, and then roasting to remove the template agent to obtain the molecular sieve catalyst.
6. The method of claim 5, wherein the template comprises a quaternary ammonium surfactant, preferably the quaternary ammonium surfactant comprises tetraethylammonium hydroxide;
the aluminum source comprises NaAlO2、Al(NO3)3、Al2(SO4)3、AlCl3Or Al (OCH (CH)3)2)3One or a combination of two or more of them;
the silicon source comprises one or the combination of more than two of silica sol, ethyl orthosilicate or sodium silicate;
the alkali source comprises sodium hydroxide or potassium hydroxide.
7. The method of preparing a molecular sieve catalyst according to claim 5 or 6,
in the precursor solution, SiO2Template agent, Al2O3Basic oxide and H2The molar ratio of O is 100 (2-20): (0-50): (0-10): 2000-6000);
the temperature of the hydrothermal crystallization treatment is 130-170 ℃, and the time of the hydrothermal crystallization treatment is 2-15 days.
8. The method for preparing the molecular sieve catalyst according to any one of claims 5 to 7, wherein the hydrothermal crystallization product is subjected to acid washing treatment by using an acid solution, so that a part of the template agent is removed from the hydrothermal crystallization product;
preferably, the acid solution is an aqueous acetic acid solution; more preferably, the mass fraction of the acetic acid aqueous solution is 20-80%; and/or
The temperature of the acid washing treatment is 20-120 ℃; the time of the acid cleaning treatment is 4-24 h.
9. The method for preparing a molecular sieve catalyst according to any one of claims 5 to 8, wherein the temperature of the ion exchange treatment is 20 ℃ to 120 ℃, and the time of the ion exchange treatment is 2h to 24 h;
the roasting is carried out in an oxygen-containing atmosphere and/or a hydrogen-containing atmosphere, the roasting temperature is 300-600 ℃, and the roasting time is 4-12 h.
10. Use of a molecular sieve catalyst according to any one of claims 1 to 4 or prepared by the preparation method of any one of claims 5 to 9 for catalytic hydrogenation, catalytic deoxygenation, catalytic oxidation or catalytic dehydrogenation reactions.
CN202010836163.9A 2020-08-19 2020-08-19 Molecular sieve catalyst, preparation method and application thereof Active CN111841623B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010836163.9A CN111841623B (en) 2020-08-19 2020-08-19 Molecular sieve catalyst, preparation method and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010836163.9A CN111841623B (en) 2020-08-19 2020-08-19 Molecular sieve catalyst, preparation method and application thereof

Publications (2)

Publication Number Publication Date
CN111841623A true CN111841623A (en) 2020-10-30
CN111841623B CN111841623B (en) 2021-09-24

Family

ID=72969252

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010836163.9A Active CN111841623B (en) 2020-08-19 2020-08-19 Molecular sieve catalyst, preparation method and application thereof

Country Status (1)

Country Link
CN (1) CN111841623B (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113042095A (en) * 2021-03-17 2021-06-29 河南大学 Molecular sieve catalyst, preparation method and application thereof
CN114506816A (en) * 2020-11-17 2022-05-17 中国科学院大连化学物理研究所 Method for preparing hydrogen by reforming methanol
CN115029768A (en) * 2021-12-28 2022-09-09 广东省科学院化工研究所 Particulate matter applied to metal piece solid electrolytic polishing and application method

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107020147A (en) * 2017-04-25 2017-08-08 天津大学 A kind of MFI structure sheet molecular sieve catalyst, the preparation method and the usage of package metals oxide or metal nanoparticle
WO2018164989A1 (en) * 2017-03-06 2018-09-13 Sabic Global Technologies B.V. Titanosilicate zeolite catalyst with encapsulated gold nanoparticles, method of synthesis and use
CN109626390A (en) * 2019-01-15 2019-04-16 太原理工大学 A kind of preparation method of multi-stage pore zeolite molecular sieve
CN109647493A (en) * 2019-01-30 2019-04-19 中国科学院过程工程研究所 A kind of pure silicon S-1 molecular sieve catalyst of package metals nano particle, preparation method and applications
CN109731608A (en) * 2019-01-30 2019-05-10 中国科学院过程工程研究所 A kind of bifunctional catalyst and preparation method thereof without sodium Si-Al molecular sieve of package metals nano particle
CN110270367A (en) * 2018-03-16 2019-09-24 天津大学 It is a kind of to encapsulate precious metals pd molecular sieve catalyst and its preparation method and application in situ
CN110627085A (en) * 2018-06-25 2019-12-31 中国石油化工股份有限公司 Preparation method and application of sulfydryl functionalized MCM (mesoporous crystalline silica) molecular sieve

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018164989A1 (en) * 2017-03-06 2018-09-13 Sabic Global Technologies B.V. Titanosilicate zeolite catalyst with encapsulated gold nanoparticles, method of synthesis and use
CN107020147A (en) * 2017-04-25 2017-08-08 天津大学 A kind of MFI structure sheet molecular sieve catalyst, the preparation method and the usage of package metals oxide or metal nanoparticle
CN110270367A (en) * 2018-03-16 2019-09-24 天津大学 It is a kind of to encapsulate precious metals pd molecular sieve catalyst and its preparation method and application in situ
CN110627085A (en) * 2018-06-25 2019-12-31 中国石油化工股份有限公司 Preparation method and application of sulfydryl functionalized MCM (mesoporous crystalline silica) molecular sieve
CN109626390A (en) * 2019-01-15 2019-04-16 太原理工大学 A kind of preparation method of multi-stage pore zeolite molecular sieve
CN109647493A (en) * 2019-01-30 2019-04-19 中国科学院过程工程研究所 A kind of pure silicon S-1 molecular sieve catalyst of package metals nano particle, preparation method and applications
CN109731608A (en) * 2019-01-30 2019-05-10 中国科学院过程工程研究所 A kind of bifunctional catalyst and preparation method thereof without sodium Si-Al molecular sieve of package metals nano particle

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
GUOZHU LIU ET AL.: ""Catalytic combustion of VOC on sandwich-structured Pt@ZSM-5 nanosheets prepared by controllable intercalation"", 《JOURNAL OF HAZARDOUS MATERIALS》 *
刘琰: ""Beta分子筛的合成及负载铂催化剂加氢脱氧性能"", 《中国优秀硕士学位论文全文数据库 工程科技Ⅰ辑》 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114506816A (en) * 2020-11-17 2022-05-17 中国科学院大连化学物理研究所 Method for preparing hydrogen by reforming methanol
CN113042095A (en) * 2021-03-17 2021-06-29 河南大学 Molecular sieve catalyst, preparation method and application thereof
CN113042095B (en) * 2021-03-17 2022-04-15 河南大学 Molecular sieve catalyst, preparation method and application thereof
CN115029768A (en) * 2021-12-28 2022-09-09 广东省科学院化工研究所 Particulate matter applied to metal piece solid electrolytic polishing and application method

Also Published As

Publication number Publication date
CN111841623B (en) 2021-09-24

Similar Documents

Publication Publication Date Title
CN111841623B (en) Molecular sieve catalyst, preparation method and application thereof
CN107020147B (en) MFI structure lamellar molecular sieve catalyst for packaging metal oxide or metal nanoparticles, and preparation method and application thereof
CN109731608B (en) Bifunctional catalyst of sodium-free silicon-aluminum molecular sieve for packaging metal nanoparticles and preparation method thereof
EP3129138B1 (en) A general method to incorporate metal nanoparticles in zeolites and zeotypes
EP3016740B1 (en) Method of producing zeolite encapsulated nanoparticles
RU2746017C2 (en) Aei high-silica zeolite
US20160074849A1 (en) Method for preparing nano metal/metal oxide loaded molecular sieve catalyst
CN102190316B (en) Method for synthesizing mesoporous mordenite
EP3016741A1 (en) Method for producing zeolites and zeotypes
EP2995377A1 (en) Catalytic materials based on functionalized ZSM-5
Chen et al. A reliable protocol for fast and facile constructing multi-hollow silicalite-1 and encapsulating metal nanoparticles within the hierarchical zeolite
CN113559916A (en) Molecular sieve encapsulated noble metal catalyst and preparation method and application thereof
CN114749207B (en) Molecular sieve encapsulated core-shell catalyst and preparation method thereof
CN114455604B (en) OFF + ERI structure msect-4 molecular sieve, preparation method and application thereof
CN113600230B (en) Efficient monoatomic molecular sieve forming catalyst and preparation method thereof
CN108097304A (en) The preparation method of Cu-SAPO-34 molecular sieve catalysts
CN108285151A (en) A kind of Ce same order elements LTL molecular sieves and preparation method thereof
JP7129063B2 (en) Zeolite containing transition metal near surface and method for producing the same
US11247196B2 (en) Zeolite with encapsulated platinum
CN115106116B (en) Catalyst with catalytic dehydrogenation function, preparation method and application thereof, and method for preparing propylene
CN108033462A (en) A kind of multi-stage porous LTL molecular sieves and its synthetic method and application
Song et al. Catalytically active Rh species stabilized by zirconium and hafnium on zeolites
CN111957311A (en) Preparation method of mesoporous-micro composite titanium-silicon material loaded Au-Pd nano catalyst
CN113042095A (en) Molecular sieve catalyst, preparation method and application thereof
CN113164943B (en) Catalyst structure for producing synthesis gas, precursor thereof, synthesis gas production apparatus, and method for producing catalyst structure for producing synthesis gas

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
CB03 Change of inventor or designer information
CB03 Change of inventor or designer information

Inventor after: Tian Yajie

Inventor after: Duan Haonan

Inventor after: Qiao Congzhen

Inventor after: Yang Hao

Inventor before: Tian Yajie

Inventor before: Duan Haonan

Inventor before: Qiao Congzhen

Inventor before: Yang Hao

GR01 Patent grant
GR01 Patent grant