CN111099614B - Noble metal titanium silicon molecular sieve, synthesis method and application thereof, and cyclohexene oxidation method - Google Patents
Noble metal titanium silicon molecular sieve, synthesis method and application thereof, and cyclohexene oxidation method Download PDFInfo
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Abstract
The invention relates to the field of molecular sieve preparation, and discloses a noble metal titanium silicalite molecular sieve, a synthesis method and application thereof, and a cyclohexene oxidation method, wherein the molecular sieve comprises the following components: the molecular sieve comprises a noble metal element, a silicon element, a titanium element and an oxygen element, wherein the ratio of the surface phase noble metal content to the bulk phase noble metal content of the molecular sieve is not more than 2. The method comprises the following steps: (1) mixing a noble metal source, an organic silicon source, a hydrolytic agent and water to obtain gel, and aging and drying the obtained gel; (2) mixing the solid product obtained in the step (1) with a template agent and water, and then carrying out hydrothermal treatment; step (1) and/or step (2) is carried out in the presence of a titanium source. The molecular sieve is particularly suitable for cyclohexene oxidation reaction, and has the advantages of high cyclohexene conversion rate and high selectivity of cyclohexanediol in an oxidation product when the molecular sieve is used in the cyclohexene oxidation reaction process.
Description
Technical Field
The invention relates to the field of molecular sieve preparation, in particular to a noble metal titanium silicalite molecular sieve, a synthesis method and application thereof, and a cyclohexene oxidation method.
Background
The titanium silicalite molecular sieve TS-1 with MFI crystal structure is a new titanium silicalite molecular sieve with excellent catalytic selective oxidation performance formed by introducing transition metal element titanium into a molecular sieve framework with a ZSM-5 structure. TS-1 not only has the catalytic oxidation effect of titanium, but also has the shape-selective effect and excellent stability of ZSM-5 molecular sieve. As the TS-1 molecular sieve can adopt the pollution-free low-concentration hydrogen peroxide as the oxidant in the oxidation reaction of the organic matters, the problems of complex process and environmental pollution in the oxidation process are avoided, and the molecular sieve has the advantages of incomparable energy conservation, economy, environmental friendliness and the like of the traditional oxidation system and has good reaction selectivity, thereby having great industrial application prospect.
The synthesis of TS-1 was first disclosed by Taramasso et al (USP 4410501). The method comprises the steps of firstly preparing a reaction mixture containing a silicon source, a titanium source, organic alkali and/or alkaline oxide, then carrying out hydrothermal crystallization on the reaction mixture in a high-pressure kettle at 130-200 ℃ for 6-30 days, and then separating, washing, drying and roasting to obtain the product. In recent years, although the technology for preparing titanium silicalite molecular sieves has been improved to some extent (such as CN101134575A and CN1247771A), the effect is not very ideal, and further improvement of the performance of titanium silicalite molecular sieves is still needed.
Disclosure of Invention
The invention aims to provide a noble metal titanium silicalite molecular sieve and a synthetic method capable of improving the catalytic performance of the titanium silicalite molecular sieve, aiming at the defects of the existing titanium silicalite molecular sieve preparation process.
To achieve the foregoing objective and in accordance with a first aspect of the present invention, there is provided a noble metal titanium silicalite molecular sieve, wherein the molecular sieve comprises: the molecular sieve comprises a noble metal element, a silicon element, a titanium element and an oxygen element, wherein the ratio of the surface phase noble metal content to the bulk phase noble metal content of the molecular sieve is not more than 2.
According to a second aspect of the present invention, there is provided a method of synthesizing a noble metal titanium silicalite molecular sieve, the method comprising:
(1) mixing a noble metal source, an organic silicon source, a hydrolytic agent and water to obtain gel, and aging and drying the obtained gel;
(2) mixing the solid product obtained in the step (1) with a template agent and water;
(3) carrying out hydrothermal treatment on the mixture obtained in the step (2) under the hydrothermal crystallization condition;
wherein step (1) and/or step (2) is carried out in the presence of a titanium source.
According to a third aspect of the present invention, there is provided a noble metal titanium silicalite molecular sieve obtainable according to the synthesis method of the present invention.
According to a fourth aspect of the present invention, there is provided a use of the noble metal titanium silicalite molecular sieve of the present invention in a cyclohexene oxidation reaction.
According to a fifth aspect of the present invention, there is provided a process for the oxidation of cyclohexene, which process comprises: under the condition of catalytic oxidation of cyclohexene, hydrogen and oxygen are contacted with a catalyst, and the catalyst is the noble metal titanium silicalite molecular sieve.
The noble metal titanium silicalite molecular sieve with the special physicochemical characteristic structure is particularly suitable for cyclohexene oxidation reaction, and when the noble metal titanium silicalite molecular sieve is used for the cyclohexene oxidation reaction, the cyclohexene conversion rate is high, and the selectivity of cyclohexanediol in an oxidation product is high.
Additional features and advantages of the invention will be set forth in the detailed description which follows.
Detailed Description
The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.
In a first aspect, the present invention provides a noble metal titanium silicalite molecular sieve, wherein the molecular sieve comprises: the molecular sieve comprises a noble metal element, a silicon element, a titanium element and an oxygen element, wherein the ratio of the surface phase noble metal content to the bulk phase noble metal content of the molecular sieve is not more than 2.
According to a preferred embodiment of the present invention, the molecular sieve has a ratio of the content of the superficial noble metal to the content of the bulk noble metal of not more than 1.8, preferably from 1.3 to 1.8. The inventors of the present invention found that the use of the molecular sieve of this preferred embodiment in cyclohexene oxidation process is more beneficial for increasing cyclohexanediol selectivity.
In the invention, the content of the surface-phase noble metal is measured by adopting an X-ray photoelectron spectroscopy method, and the content of the bulk-phase noble metal is measured by adopting an X-ray fluorescence spectroscopy method.
According to the invention, the total specific surface area of the molecular sieve is preferably 350m2More than g, preferably 400-800m2(iv)/g, more preferably 400-2/g。
According to the invention, preferably, the molecular sieve has an external surface area of 20m2A molar ratio of 25m or more2A total of 40 to 150m per gram2/g。
In the present invention, the total specific surface area of the noble metal titanium silicalite molecular sieve refers to BET specific surface area, and the external specific surface area refers to the surface area of the external surface of the noble metal titanium silicalite molecular sieve, which may also be referred to as external surface area, all of which can be measured according to ASTM D4222-98 standard method.
According to a preferred embodiment of the invention, the proportion of the external surface area to the total specific surface area is 5 to 25%, more preferably 20 to 25%.
According to a preferred embodiment of the present invention, the molecular sieve has a mesoporous pore size distribution in a range of 2-6nm, and further preferably, the ratio of the mesoporous pore size in the range of 2-6nm in the molecular sieve to the total mesoporous pore size distribution is greater than or equal to 10%, preferably 20-50%. In the present invention, the mesoporous diameter of the noble metal titanium silicalite molecular sieve refers to the pore diameter of mesopores in the molecular sieve, which is well known to those skilled in the art and will not be described herein.
The proportion of the mesoporous aperture within the range of 2-6nm in the total mesoporous aperture distribution quantity is calculated according to the following formula: (the number of mesoporous pores in the range of 2 to 6 nm/the number of mesoporous pores in the range of 2 to 50 nm) × 100%. The method for measuring the pore diameter of the mesoporous is well known to those skilled in the art, and for example, the method is to use static adsorption of nitrogen gas.
According to a preferred embodiment of the invention, the percentage of the mesopore volume of the molecular sieve based on the total pore volume is from 30 to 60%, preferably from 35 to 55%. The mesoporous volume and the total pore volume of the molecular sieve can be tested by methods such as nitrogen static adsorption and the like.
According to a preferred embodiment of the present invention, the molecular sieve has a bulk precious metal content of not more than 5 wt.%, preferably 0.02 to 5 wt.%, more preferably 0.05 to 4 wt.%.
According to a preferred embodiment of the present invention, the mass ratio of the noble metal element, the titanium element and the silicon element is 0.05 to 10: 0.1-6: 100, more preferably 0.1 to 5: 0.2-5: 100, more preferably 0.3 to 3.4: 1.3-1.9:100.
According to a preferred embodiment of the present invention, the noble metal is one or more of Ru, Rh, Pd, Re, Os, Ir, Pt, Ag and Au, more preferably one or more of Ru, Rh, Pd, Pt, Ag and Au, and still more preferably Pd and/or Pt.
The noble metal titanium silicalite molecular sieve has a special physical and chemical characteristic structure, is used for cyclohexene oxidation reaction, is beneficial to improving the conversion rate of cyclohexene, and has higher selectivity of cyclohexanediol. The present invention has no special requirement on the preparation method of the noble metal titanium silicalite molecular sieve, as long as the noble metal titanium silicalite molecular sieve with the structure can be prepared, and according to a preferred embodiment of the present invention, the noble metal titanium silicalite molecular sieve is prepared by a method comprising the following steps:
(1) mixing a noble metal source, an organic silicon source, a hydrolytic agent and water to obtain gel, and aging and drying the obtained gel;
(2) mixing the solid product obtained in the step (1) with a template agent and water;
(3) carrying out hydrothermal treatment on the mixture obtained in the step (2) under the hydrothermal crystallization condition;
wherein step (1) and/or step (2) is carried out in the presence of a titanium source.
According to the present invention, preferably, the step (1) comprises: the noble metal source and the organic silicon source are mixed, and then the hydrolytic agent is added. The hydrolyzing agent hydrolyzes the organic silicon source. In the present invention, the kind and amount of the hydrolyzing agent are not particularly limited as long as the organic silicon source can be hydrolyzed.
According to the present invention, preferably, the hydrolysis agent is an acid and/or a base, more preferably an inorganic acid and/or an inorganic base, and still more preferably, the hydrolysis agent is at least one of hydrochloric acid, nitric acid and ammonia water.
The amount of water used in step (1) is not particularly limited in the present invention, and may be introduced together with the hydrolyzing agent as long as the amount of water required for the hydrolysis of the organic silicon source is satisfied.
According to the present invention, preferably, the mixing conditions of step (1) include: the temperature is 20-80 ℃ and the time is 1-240min, more preferably, the temperature is 25-60 ℃ and the time is 100-. In the embodiment of the present invention, the temperature is 25 ℃ and the time is 180min for example, but the present invention is not limited thereto. According to a particular embodiment of the invention, the mixing of step (1) is carried out under stirring conditions.
According to the present invention, preferably, the aging conditions of step (1) include: the temperature is 60-100 deg.C, and the time is 6-36h, more preferably 70-90 deg.C, and the time is 8-24 h. According to the method provided by the invention, the noble metal source and the organic silicon source are introduced before aging, the hydrolyzing agent is added to hydrolyze the organic silicon source to form gel, and aging is carried out subsequently, so that the noble metal is firmly wrapped in the silicon substance.
The drying conditions in step (1) are not particularly limited in the present invention, and may be, for example, drying at 80 to 120 ℃ for 2 to 10 hours.
According to the method provided by the present invention, the titanium source may be introduced in step (1), or in step (2), or in both step (1) and step (2), and the present invention is not particularly limited thereto, but in order to further improve the catalytic performance of the molecular sieve produced, it is preferable that step (2) is performed in the presence of the titanium source. Preferably, step (2) comprises: mixing the solid product obtained in the step (1), a titanium source, a template and water.
According to a preferred embodiment of the invention, the organic silicon source: a titanium source: template agent:noble metal sources: the total using molar ratio of water is 100: (0.05-10): (0.005-20): (0.05-15): (20-1500), more preferably 100: (0.5-5): (5-20): (0.05-8): (100-1200), more preferably 100: (1-2): (10-18): (0.1-4): (200-800), wherein the organic silicon source is SiO2The titanium source is calculated as TiO2Counting and counting template agent by N or OH-The noble metal source is calculated by noble metal elements.
According to the method of the present invention, the hydrothermal crystallization conditions can be selected in a wide range, and for the present invention, it is preferable that the hydrothermal crystallization conditions include: the reaction is carried out under a closed condition, the temperature is 80-200 ℃, the time is 6-200h, preferably the temperature is 100-180 ℃, the time is 24-160h, more preferably the temperature is 130-175 ℃, and the time is 24-144 h.
The hydrothermal treatment in step (3) of the present invention may be performed in a reaction vessel.
In a preferred method of the present invention, in order to improve the catalytic oxidation activity of the noble metal titanium silicalite molecular sieve, the hydrothermal crystallization conditions include: the reaction kettle contains water which forms saturated water vapor under hydrothermal crystallization conditions and has a weight ratio of the saturated water vapor to the solid product obtained in the step (1) of less than 1.2 (referring to the molar ratio of the materials, namely, more preferably, the weight ratio of the solid product obtained in the step (1) to the water is 100: 30-120, the molar ratio is 100: 1-4), and the handling capacity of the solid product obtained in the step (1) is at least 10 g/l (volume of the reaction kettle). In the reaction kettle, the amount ratio of water is preferably not more than the amount of saturated vapor adsorbed by the solid product obtained in step (1). In the system of the invention, basically enough saturated steam quantity can be provided for the space, but the residual water is less than the saturated adsorption quantity of the solid product obtained in the step (1). In other words, it is necessary that the saturated adsorption amount of the solid product obtained in the step (1) is not exceeded, but it is generally sufficient that the reaction system is at saturated humidity (water vapor amount). This is why the solution of the present invention requires controlling the amount of water contained in the reaction vessel which forms saturated water vapor under hydrothermal crystallization conditions and has a weight ratio to the solid product obtained in step (1) of less than 1.2, and the amount of the solid product obtained in step (1) to be treated is at least 10 g/l (volume of the reaction vessel). For example, if a reaction vessel with a volume of 100ml requires 0.5 g of water to reach saturation humidity, the solid product obtained in step (1) may be 20 g or 1 g. If 0.2g of adsorbed water is added to 1g of the solid product obtained in step (1), 20 g of the solid product obtained in step (1) cannot exceed 4 g of water at most, but at least 0.5 g of water is added.
According to the method of the present invention, the noble metal source can be selected in a wide range, and any noble metal-containing substance (for example, a noble metal element-containing compound and/or a noble metal simple substance) can achieve the object of the present invention. Preferably, the noble metal source is one or more of an oxide of a noble metal, a halide of a noble metal, a carbonate of a noble metal, a nitrate of a noble metal, an ammonium nitrate salt of a noble metal, an ammonium chloride salt of a noble metal, a hydroxide of a noble metal, and a complex of a noble metal. The noble metal is selected as described above and will not be described in detail here. Taking palladium as an example, the noble metal source is selected from one or more of palladium oxide, palladium carbonate, palladium chloride, palladium nitrate, palladium ammonium nitrate, palladium ammine chloride, palladium acetate, palladium hydroxide, palladium complex, palladium acetate and palladium acetylacetonate. In the examples of the present invention, platinum nitrate, palladium chloride, and palladium ammine chloride are used as examples for the description.
According to the method of the present invention, the organic silicon source may be various silicon-containing compounds capable of forming silica under hydrolytic condensation reaction conditions. Specifically, the organic silicon source may be one or more selected from silicon-containing compounds represented by formula I,
in the formula I, R1、R2、R3And R4Each is C1-C4Alkyl of (2) including C1-C4Straight chain alkyl of (2) and C3-C4Branched alkyl groups of (a), for example: r1、R2、R3And R4Each may be methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl or tert-butyl.
According to an embodiment of the present invention, the organic silicon source may be one or more of tetramethyl orthosilicate, tetraethyl orthosilicate, tetra-n-propyl orthosilicate, and tetra-n-butyl orthosilicate. In the specific embodiments of the present invention, tetraethoxysilane is used as an example, but the scope of the present invention is not limited thereto.
According to the process of the present invention, the titanium source may be selected as is conventional in the art, and for the purposes of the present invention, preferably the titanium source is selected from inorganic titanium salts and/or organic titanates, further preferably organic titanates.
In the present invention, the inorganic titanium salt is selected from various hydrolyzable titanium salts, and may be selected from TiX, for example4、TiOX2Or Ti (SO)4)2And the like, wherein X is halogen, preferably chlorine, wherein preferably the inorganic titanium salt is selected from TiCl4、Ti(SO4)2And TiOCl2One or more of (a).
In the present invention, the organic titanate is preferably of the formula M4TiO4Wherein M is preferably an alkyl group having 1 to 4 carbon atoms, and 4M's may be the same or different, preferably the organotitanate is selected from one or more of isopropyl titanate, n-propyl titanate, tetrabutyl titanate and tetraethyl titanate, tetrabutyl titanate being used as an example in the specific embodiment of the present invention, but not thereby limiting the scope of the present invention.
In the present invention, the templating agent may be various templating agents conventionally used in the art, such as: the templating agent may be one or more of a quaternary ammonium base, an aliphatic amine, and an aliphatic alcohol amine. The quaternary ammonium base can be various organic quaternary ammonium bases, and the aliphatic amine can be various NH3Wherein at least one hydrogen is substituted with an aliphatic hydrocarbon group (e.g., an alkyl group), and the aliphatic alcohol amine may be any of various compoundsNH3Wherein at least one hydrogen is substituted with a hydroxyl-containing aliphatic group (e.g., an alkyl group).
Specifically, the template agent may be one or more selected from the group consisting of a quaternary ammonium base represented by formula II, an aliphatic amine represented by formula III, and an aliphatic alcohol amine represented by formula IV.
In the formula I, R1、R2、R3And R4Each is C1-C4Alkyl of (2) including C1-C4Straight chain alkyl of (2) and C3-C4Branched alkyl groups of (a), for example: r1、R2、R3And R4Each may be methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl or tert-butyl.
R5(NH2)n(formula III)
In the formula II, n is an integer of 1 or 2. When n is 1, R5Is C1-C6Alkyl of (2) including C1-C6Straight chain alkyl of (2) and C3-C6Such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, neopentyl, isopentyl, tert-pentyl and n-hexyl. When n is 2, R5Is C1-C6Alkylene of (2) including C1-C6Linear alkylene of (A) and (C)3-C6Such as methylene, ethylene, n-propylene, n-butylene, n-pentylene or n-hexylene.
(HOR6)mNH(3-m)(formula IV)
In the formula III, m R6Are the same or different and are each C1-C4Alkylene of (2) including C1-C4Linear alkylene of (A) and (C)3-C4Branched alkylene groups of (a), such as methylene, ethylene, n-propylene and n-butylene; m is 1, 2 or 3.
The template may specifically be, but is not limited to: one or more of tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide (including various isomers of tetrapropylammonium hydroxide, such as tetra-n-propylammonium hydroxide and tetraisopropylammonium hydroxide), tetrabutylammonium hydroxide (including various isomers of tetrabutylammonium hydroxide, such as tetra-n-butylammonium hydroxide and tetraisobutylammonium hydroxide), ethylamine, n-propylamine, n-butylamine, di-n-propylamine, butanediamine, hexanediamine, monoethanolamine, diethanolamine, and triethanolamine. Preferably, the templating agent is tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide. The examples of the present invention are exemplified by tetrapropylammonium hydroxide, but the present invention is not limited thereto.
According to the present invention, it is preferred that the method of the present invention further comprises a step of recovering a product from the hydrothermally treated material of step (3), the step of recovering the product being a conventional method familiar to those skilled in the art, and generally means a process of filtering, washing, drying and calcining the product, without any particular requirement. Wherein the drying process can be carried out at a temperature of between room temperature and 200 ℃, and the roasting process can be carried out at a temperature of between 300 ℃ and 800 ℃ for 3 to 12 hours.
In a third aspect, the invention provides a noble metal titanium silicalite molecular sieve obtained according to the synthesis method of the invention.
The fourth aspect of the invention provides the use of the noble metal titanium silicalite molecular sieve of the invention in cyclohexene oxidation reactions. The inventor of the invention finds that the noble metal titanium silicalite molecular sieve with the special physical and chemical characteristic structure is particularly suitable for cyclohexene oxidation reaction, and when the noble metal titanium silicalite molecular sieve is used for the cyclohexene oxidation reaction, the cyclohexene conversion rate is high, and the cyclohexanediol selectivity in an oxidation product is high.
In a fifth aspect, the present invention provides a method for oxidation of cyclohexene, which comprises: under the condition of catalytic oxidation of cyclohexene, hydrogen and oxygen are contacted with a catalyst, and the catalyst is the noble metal titanium silicalite molecular sieve.
According to the method provided by the present invention, preferably, the cyclohexene catalytic oxidation conditions include: the temperature is 0 to 180 ℃, preferably 20 to 160 ℃, more preferably 40 to 120 ℃, and the pressure is 0.1 to 5MPa, preferably 0.5 to 4MPa, more preferably 1 to 3 MPa. According to the process of the present invention, the contact time of the cyclohexene, hydrogen and oxygen with the catalyst may be suitably selected. Generally, the contact time may be from 0.1 to 10 hours, preferably from 1 to 5 hours.
According to the process of the present invention, the contacting may be carried out in an autoclave. Preferably, the contacting process further comprises introducing an inert gas, such as nitrogen. Specifically, inert gas, hydrogen and oxygen are introduced into the autoclave so that the pressure in the autoclave reaches the above pressure. The volume ratio of the inert gas, hydrogen gas and oxygen gas is not particularly limited according to the present invention. In the embodiment of the invention, the volume ratio of inert gas, hydrogen and oxygen is 3: 1: the example 1 is illustrative.
According to one embodiment of the invention, the contacting is carried out in the presence of a solvent. The solvent is preferably selected from one or more of water, methanol, ethanol, n-propanol, isopropanol, tert-butanol, isobutanol, acetone, butanone, acetonitrile, propionitrile, phenylacetonitrile, acetic acid and propionic acid, more preferably the solvent is selected from one or more of acetonitrile, acetone, methanol, acetic acid and water, most preferably methanol.
According to a preferred embodiment of the present invention, cyclohexene is used in an amount of 0.1 to 200mL, preferably 1 to 150mL, more preferably 10 to 100mL, relative to 1g of catalyst.
According to a preferred embodiment of the invention, the solvent is used in an amount of 1 to 2000mL, preferably 10 to 1000mL, relative to 1g of catalyst.
The following examples further illustrate the invention but do not limit the scope of the invention. All reagents used in the examples and comparative examples were commercially available chemically pure reagents.
In the following examples and comparative examples, water was added or not added as required during the mixing process, and if the feed can meet the feed requirement of water, no water was added, and if not, additional water was added.
The pore volume, pore size distribution, total specific surface area and external specific surface area of the sample were measured on a Micromeritics ASAP2405 static nitrogen adsorber.
The elemental composition of the sample, such as noble metal, titanium, and silicon, was measured by a 3271E model X-ray fluorescence spectrometer, manufactured by Nippon Denshi electric motors Co.
The content of the surface phase noble metal is measured by an ESCALB 250 type X-ray photoelectron spectrometer of Thermo Scientific company; the bulk precious metal content was measured by means of a 3271E model X-ray fluorescence spectrometer, manufactured by Nippon Denshi electric motors Co.
Example 1
(1) Stirring and contacting tetraethoxysilane and palladium chloride for 30min at 25 ℃, adding hydrochloric acid with the mass fraction of 10% to hydrolyze tetraethoxysilane, continuously stirring and mixing for 3h to obtain gel, aging for 12h at 80 ℃, and drying for 120 min at 110 ℃. (2) And (2) stirring and contacting the solid product obtained in the step (1), a template agent tetrapropylammonium hydroxide, titanium source tetrabutyl titanate and water for 0.5h at 25 ℃, wherein the organic silicon source (ethyl orthosilicate): titanium source (tetrabutyl titanate): template (tetrapropylammonium hydroxide): noble metal source (palladium chloride): water molar ratio of 100: 2: 10: 1.5: 500, wherein the organic silicon source is SiO2The noble metal source is calculated by noble metal element, the titanium source is calculated by TiO2In terms of OH as template agent-And (6) counting. (3) And transferring the mixture into a stainless steel sealed reaction kettle, crystallizing for 144 hours at the temperature of 170 ℃ and the autogenous pressure, filtering the obtained crystallized product, washing with water, drying for 120 minutes at the temperature of 110 ℃, and roasting for 3 hours at the temperature of 550 ℃ to obtain the noble metal titanium-silicon molecular sieve. The composition and properties are shown in table 1.
Comparative example 1
The procedure of example 1 was followed, except that step (1) did not include aging and drying procedures, to obtain a noble metal titanium silicalite molecular sieve. The composition and properties are shown in table 1.
Comparative example 2
The procedure is as in example 1, except that SiO2Replacing the organic silicon source with the same molar weightInorganic silicon source silica gel (product from Qingdao silica gel factory, SiO)2Has a mass fraction of more than 95%, an average pore diameter of 2.6nm and a specific surface area of 680m2G, pore volume 0.38 ml/g). Obtaining the noble metal titanium-silicon molecular sieve. The composition and properties are shown in table 1.
Example 2
(1) Stirring and contacting ethyl orthosilicate, tetrabutyl titanate and palladium ammonium chloride for 30min at 25 ℃, adding ammonia water with the mass fraction of 10% to hydrolyze the ethyl orthosilicate, continuously stirring and mixing for 3h to obtain gel, aging for 24h at 70 ℃, and drying for 120 min at 110 ℃. (2) Stirring and contacting the solid product obtained in the step (1), a template agent tetrapropylammonium hydroxide and water for 0.5h, wherein the organic silicon source (tetraethoxysilane): titanium source (tetrabutyl titanate): template (tetrapropylammonium hydroxide): noble metal source (palladium ammine chloride): water molar ratio of 100: 1: 15: 0.1: 800, wherein the organic silicon source is SiO2The noble metal source is calculated by noble metal element, the titanium source is calculated by TiO2In terms of OH as template agent-And (6) counting. (3) And transferring the mixture into a stainless steel sealed reaction kettle, crystallizing for 120 hours at the temperature of 160 ℃ and the autogenous pressure, filtering the obtained crystallized product, washing with water, drying for 120 minutes at the temperature of 110 ℃, and roasting for 3 hours at the temperature of 550 ℃ to obtain the noble metal titanium-silicon molecular sieve. The composition and properties are shown in table 1.
Comparative example 3
The procedure of example 2 is followed except that the noble metal is added in step (2), specifically:
(1) stirring and contacting tetraethoxysilane and tetrabutyl titanate for 30min at 25 ℃, adding ammonia water with the mass fraction of 10% to hydrolyze tetraethoxysilane, continuously stirring and mixing for 3h to obtain gel, aging for 24h at 70 ℃, and drying for 120 min at 110 ℃. (2) Stirring and contacting the solid product obtained in the step (1), palladium ammonium chloride, a template agent tetrapropylammonium hydroxide and water for 0.5h, wherein an organic silicon source (ethyl orthosilicate): titanium source (tetrabutyl titanate): template (tetrapropylammonium hydroxide): noble metal source (palladium ammine chloride): water molar ratio of 100: 1: 15: 0.1: 800, wherein the organic silicon source is SiO2In terms of noble metal element, the noble metal source is in terms of titanium sourceTiO2In terms of OH as template agent-And (6) counting. (3) And transferring the mixture into a stainless steel sealed reaction kettle, crystallizing for 120 hours at the temperature of 160 ℃ and the autogenous pressure, filtering the obtained crystallized product, washing with water, drying for 120 minutes at the temperature of 110 ℃, and roasting for 3 hours at the temperature of 550 ℃ to obtain the noble metal titanium-silicon molecular sieve. The compositions and properties are shown in Table 1
Example 3
(1) Stirring and contacting tetraethoxysilane and platinum nitrate for 30min at 25 ℃, adding nitric acid with the mass fraction of 15% to hydrolyze tetraethoxysilane, continuously stirring and mixing for 3h to obtain gel, aging for 8h at 90 ℃, and drying for 120 min at 110 ℃. (2) And (2) stirring and contacting the solid product obtained in the step (1), a template agent tetrapropylammonium hydroxide, titanium source tetrabutyl titanate and water for 0.5h at 25 ℃, wherein the organic silicon source (ethyl orthosilicate): titanium source (tetrabutyl titanate): template (tetrapropylammonium hydroxide): noble metal source (platinum nitrate): water molar ratio of 100: 1: 18: 4: 600, wherein the organic silicon source is SiO2The noble metal source is calculated by noble metal element, the titanium source is calculated by TiO2In terms of OH as template agent-And (6) counting. (3) And transferring the mixture into a stainless steel sealed reaction kettle, crystallizing for 144 hours at the temperature of 170 ℃ and the autogenous pressure, filtering the obtained crystallized product, washing with water, drying for 120 minutes at the temperature of 110 ℃, and roasting for 3 hours at the temperature of 550 ℃ to obtain the noble metal titanium-silicon molecular sieve. The composition and properties are shown in table 1.
Example 4
The procedure of example 1 was followed except that the aging temperature was 130 ℃. Obtaining the noble metal titanium-silicon molecular sieve. The composition and properties are shown in table 1.
Example 5
The procedure of example 1 was followed except that the aging temperature was 40 ℃. Obtaining the noble metal titanium-silicon molecular sieve. The composition and properties are shown in table 1.
In the context of table 1, the following,
a represents the percentage of the volume of mesopores in the molecular sieve to the total pore volume;
b represents the proportion of the mesoporous aperture within the range of 2-6nm in the molecular sieve in the total mesoporous aperture distribution amount;
c represents the ratio of the surface phase noble metal content to the bulk phase noble metal content in the molecular sieve.
TABLE 1
Test example 1
This test example is presented to illustrate the use of the noble metal titanium silicalite molecular sieves of the present invention in cyclohexene oxidation and the cyclohexene oxidation process.
0.2g of noble metal titanium silicalite molecular sieves prepared in the comparative example and the example, 15mL of cyclohexene and 80mL of methanol solvent are respectively added into a 250mL high-pressure closed reaction kettle, and then nitrogen, hydrogen and oxygen are mixed according to the ratio of 3: 1: the volume ratio of 1 is introduced into a high-pressure closed reaction kettle until the pressure reaches 3MPa and is maintained, and the result after 3 hours of reaction is shown in Table 2.
Wherein:
TABLE 2
As can be seen from Table 2, the noble metal titanium silicalite molecular sieve prepared by the invention has better catalytic oxidation activity and better cyclohexanediol selectivity compared with the common noble metal titanium silicalite molecular sieve. Meanwhile, the yield of the noble metal titanium silicalite molecular sieve prepared by the optimal method is high.
The preferred embodiments of the present invention have been described above in detail, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the scope of the invention.
Claims (29)
1. A noble metal titanium silicalite molecular sieve, wherein the molecular sieve comprises: the molecular sieve comprises noble metal elements, silicon elements, titanium elements and oxygen elements, wherein the ratio of the surface phase noble metal content to the bulk phase noble metal content of the molecular sieve is not more than 2;
the preparation method of the noble metal titanium silicalite molecular sieve comprises the following steps:
(1) mixing a noble metal source, an organic silicon source, a hydrolytic agent and water to obtain gel, and aging and drying the obtained gel;
(2) mixing the solid product obtained in the step (1) with a template agent and water;
(3) carrying out hydrothermal treatment on the mixture obtained in the step (2) under the hydrothermal crystallization condition;
wherein step (1) and/or step (2) is carried out in the presence of a titanium source.
2. The molecular sieve of claim 1, wherein the molecular sieve has a ratio of a superficial phase noble metal content to a bulk phase noble metal content of no greater than 1.8.
3. The molecular sieve of claim 1, wherein the molecular sieve has a ratio of a superficial phase noble metal content to a bulk phase noble metal content of from 1.3 to 1.8.
4. The molecular sieve of claim 1, wherein the molecular sieve has a mesoporous pore size distribution in the range of 2-6 nm.
5. The molecular sieve of claim 4, wherein the proportion of the mesoporous aperture within the range of 2-6nm in the molecular sieve to the total mesoporous aperture distribution is not less than 10%.
6. The molecular sieve of claim 4, wherein the molecular sieve has a mesopore diameter ranging from 2 nm to 6nm accounting for 20-50% of the total mesopore diameter distribution.
7. The molecular sieve of claim 1, wherein the molecular sieve has a total specific surface area of 350m2More than g, the external surface area is 20m2More than g.
8. The molecular sieve of claim 1, wherein the total specific surface area of the molecular sieve is 400-800m2/g。
9. The molecular sieve of claim 1, wherein the molecular sieve has an external surface area of 25m2More than g.
10. The molecular sieve of claim 1, wherein the molecular sieve has an external surface area of 40-150m2/g。
11. The molecular sieve of claim 1, wherein the molecular sieve has an external surface area in the range of 5 to 25% of the total specific surface area.
12. The molecular sieve of any of claims 1-11, wherein the molecular sieve has a bulk noble metal content of no greater than 5 wt.%.
13. The molecular sieve of claim 12, wherein the molecular sieve has a bulk noble metal content of 0.02 to 5 wt.%.
14. The molecular sieve of claim 12, wherein the molecular sieve has a bulk noble metal content of 0.05 to 4 wt.%.
15. The molecular sieve according to any one of claims 1 to 11, wherein the mass ratio of the noble metal element, the titanium element and the silicon element is 0.05 to 10: 0.1-6: 100.
16. a method for synthesizing a noble metal titanium silicalite molecular sieve, comprising:
(1) mixing a noble metal source, an organic silicon source, a hydrolytic agent and water to obtain gel, and aging and drying the obtained gel;
(2) mixing the solid product obtained in the step (1) with a template agent and water;
(3) carrying out hydrothermal treatment on the mixture obtained in the step (2) under the hydrothermal crystallization condition;
wherein step (1) and/or step (2) is carried out in the presence of a titanium source.
17. The method of claim 16, wherein the conditions of the mixing of step (1) comprise: the temperature is 20-80 deg.C, and the time is 1-240 min.
18. The method of claim 16, wherein the aging conditions of step (1) comprise: the temperature is 60-100 ℃, and the time is 6-36 h.
19. The method of claim 16, wherein,
the hydrolytic agent in the step (1) is acid and/or alkali.
20. The method of claim 16, wherein the hydrolyzing agent of step (1) is at least one of hydrochloric acid, nitric acid, and ammonia.
21. The method of claim 16, wherein the hydrothermal crystallization conditions of step (3) comprise: the preparation is carried out under the closed condition, the temperature is 80-200 ℃, and the time is 6-200 h.
22. The method of claim 16, wherein the hydrothermal crystallization conditions of step (3) comprise: the temperature is 100-180 ℃, and the time is 24-160 h.
23. The method of claim 16, wherein step (3) is performed in a reaction vessel and the hydrothermal crystallization conditions comprise: the reaction kettle contains water which forms saturated water vapor under the hydrothermal crystallization condition and has the weight ratio of the saturated water vapor to the solid product obtained in the step (1) less than 1.2.
24. The method of any one of claims 16-23, wherein step (2) is performed in the presence of a titanium source.
25. The method of any one of claims 16-23, wherein the organic silicon source: a titanium source: template agent: noble metal sources: the total using molar ratio of water is 100: (0.05-10): (0.005-20): (0.05-15): (20-1500), wherein the organic silicon source is SiO2The titanium source is calculated as TiO2Counting and counting template agent by N or OH-The noble metal source is calculated by noble metal elements.
26. The method of any one of claims 16-23, wherein the organic silicon source: a titanium source: template agent: noble metal sources: the total using molar ratio of water is 100: (0.5-5): (5-20): (0.05-8): (100-1200), wherein the organic silicon source is SiO2The titanium source is calculated as TiO2Counting and counting template agent by N or OH-The noble metal source is calculated by noble metal elements.
27. A noble metal titanium silicalite molecular sieve produced by the process of any one of claims 16 to 26.
28. Use of the noble metal titanium silicalite molecular sieve of any one of claims 1-15, 27 in cyclohexene oxidation.
29. A process for the oxidation of cyclohexene, which process comprises: under the condition of catalytic oxidation of cyclohexene, hydrogen and oxygen are contacted with a catalyst, wherein the catalyst is the noble metal titanium silicalite molecular sieve as claimed in any one of claims 1-15 and 27.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2001083467A1 (en) * | 2000-04-27 | 2001-11-08 | Arco Chemical Technology, L.P. | Aqueous epoxidation process using modified titanium zeolite |
| CN1724159A (en) * | 2005-05-24 | 2006-01-25 | 太原理工大学 | Composite oxide load type catalyst and preparation process thereof |
| CN101623653A (en) * | 2008-07-10 | 2010-01-13 | 中国石油化工股份有限公司 | Method for modifying titanium-silicon molecular sieve material |
| CN103357432A (en) * | 2013-08-07 | 2013-10-23 | 华东理工大学 | Mesoporous titanium-silicon molecular sieve, and preparation method and application thereof |
| CN106179474A (en) * | 2015-04-30 | 2016-12-07 | 中国石油化工股份有限公司 | A kind of Hydrobon catalyst and preparation method thereof |
| CN106904632A (en) * | 2015-12-23 | 2017-06-30 | 中国石油化工股份有限公司 | A kind of HTS and its synthetic method and application and a kind of method for hydroxylation of phenol |
| CN107879354A (en) * | 2016-09-30 | 2018-04-06 | 中国石油化工股份有限公司 | A kind of HTS and its synthetic method and application and a kind of method of cyclic ketones oxidation |
| CN107879356A (en) * | 2016-09-30 | 2018-04-06 | 中国石油化工股份有限公司 | A kind of HTS and its synthetic method and application and a kind of method of cyclic ketones oxidation |
| CN107986293A (en) * | 2016-10-27 | 2018-05-04 | 中国石油化工股份有限公司 | A kind of Titanium Sieve Molecular Sieve and its synthetic method and application |
-
2018
- 2018-10-29 CN CN201811270008.4A patent/CN111099614B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2001083467A1 (en) * | 2000-04-27 | 2001-11-08 | Arco Chemical Technology, L.P. | Aqueous epoxidation process using modified titanium zeolite |
| CN1724159A (en) * | 2005-05-24 | 2006-01-25 | 太原理工大学 | Composite oxide load type catalyst and preparation process thereof |
| CN101623653A (en) * | 2008-07-10 | 2010-01-13 | 中国石油化工股份有限公司 | Method for modifying titanium-silicon molecular sieve material |
| CN103357432A (en) * | 2013-08-07 | 2013-10-23 | 华东理工大学 | Mesoporous titanium-silicon molecular sieve, and preparation method and application thereof |
| CN106179474A (en) * | 2015-04-30 | 2016-12-07 | 中国石油化工股份有限公司 | A kind of Hydrobon catalyst and preparation method thereof |
| CN106904632A (en) * | 2015-12-23 | 2017-06-30 | 中国石油化工股份有限公司 | A kind of HTS and its synthetic method and application and a kind of method for hydroxylation of phenol |
| CN107879354A (en) * | 2016-09-30 | 2018-04-06 | 中国石油化工股份有限公司 | A kind of HTS and its synthetic method and application and a kind of method of cyclic ketones oxidation |
| CN107879356A (en) * | 2016-09-30 | 2018-04-06 | 中国石油化工股份有限公司 | A kind of HTS and its synthetic method and application and a kind of method of cyclic ketones oxidation |
| CN107986293A (en) * | 2016-10-27 | 2018-05-04 | 中国石油化工股份有限公司 | A kind of Titanium Sieve Molecular Sieve and its synthetic method and application |
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