CN115991484A - Mesoporous composite molecular sieve and preparation thereof, normal alkane hydroisomerization catalyst and preparation and application thereof - Google Patents
Mesoporous composite molecular sieve and preparation thereof, normal alkane hydroisomerization catalyst and preparation and application thereof Download PDFInfo
- Publication number
- CN115991484A CN115991484A CN202211580740.8A CN202211580740A CN115991484A CN 115991484 A CN115991484 A CN 115991484A CN 202211580740 A CN202211580740 A CN 202211580740A CN 115991484 A CN115991484 A CN 115991484A
- Authority
- CN
- China
- Prior art keywords
- molecular sieve
- composite molecular
- mesoporous
- mesoporous composite
- preparation
- 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.)
- Pending
Links
Images
Abstract
The invention provides a mesoporous composite molecular sieve, a preparation method thereof, an n-alkane hydroisomerization catalyst and a preparation method and application thereof, wherein the mesoporous composite molecular sieve is prepared by compositing microporous mordenite molecular sieve with organic-inorganic hybrid mesoporous silica, has mesoporous and microporous double-pore distribution and double hysteresis rings, and has a specific surface area of 400-850m 2 ·g ‑1 Pore volume of 0.35-0.85cm 3 ·g ‑1 The aperture is 5-8nm. The mesoporous composite molecular sieve material provided by the invention has the advantages of high specific surface area, large aperture and adjustable acidity, and the catalyst obtained by taking the mesoporous composite molecular sieve material as a carrier to load noble metal is more suitable for catalyzing normal alkane hydroisomerization reaction, has higher catalytic activity and selectivity, and increases along with the increase of the reaction temperatureThe conversion increases gradually.
Description
Technical Field
The invention relates to a mesoporous composite molecular sieve and a preparation method thereof, and a normal alkane hydroisomerization catalyst and a preparation method and application thereof, belonging to the technical field of normal alkane hydroisomerization.
Background
Along with the gradual strictness of environmental protection requirements and the standards of finished oil, the gasoline is developed towards low sulfur, low nitrogen, low aromatic hydrocarbon and high octane number, the production of ultra-clean high-octane gasoline is in trend of great trend, normal paraffins have lower octane number, and branched isoparaffin has high octane number, so that the octane number of the gasoline is improved, and the normal paraffins are ideal blending components in the gasoline, so that the normal paraffins isomerization technology is attracting more and more attention. The n-heptane is converted into the isoheptane through hydroisomerization, so that the octane number of the gasoline can be greatly improved, and the combustion performance of the gasoline is excellent, and the products after the engine burns have no SOx and NOx, so that the research on the n-alkane hydroisomerization process technology is significant for producing the ultra-clean high-octane number gasoline.
Since the 60 s of the last century, various research institutes in China began hydroisomerization technology research, mainly RISO isomerization technology developed by the institute of petrochemical technology (RIPP) and adopting the reaction scheme of deisopentane+isomerization, and isomerization technology developed by the university of eastern chemical industry, namely Jinling petrochemical industry, all adopted the reaction scheme of 'one pass', so that the octane number of the product is improved by more than 10 units. For the isomerization catalyst, a bifunctional catalyst containing noble metal is widely used in industry for isomerization of alkane, and the catalyst can be divided into aluminum chloride (Pt/Cl-Al) 2 O 3 ) Solid superacid type (Pt/ZrO) 2 -SO 4 2- ) And molecular sieves (Pt/molecular sieves), etc.; the reaction temperature can be divided into low temperature type<200 ℃ aluminum chloride type and solid super acidic type) and medium temperature type>200 ℃, molecular sieve type), among which are the commercial solid acid catalysts of the GCS-1 type of the beijing college of the sciences and the LPI-100 type of the catalyst developed by the company uip, holmivir, usa. In hydroisomerization techniques, the catalyst greatly affects the degree of isomerization, and the catalysts typically used for hydroisomerization are those used forA metal center for hydrogenation/dehydrogenation and an acid center for skeletal isomerization; in addition, the acidity level has a great influence on the activity of isomerization. The bifunctional catalyst mainly comprises: solid superacid catalyst, low temperature halogen (AlCl) 3 ) The type catalyst and the molecular sieve type catalyst, wherein the molecular sieve type catalyst has stronger acidity and good pore channel structure, are widely studied at present.
The molecular sieve type catalyst is prepared by taking mordenite, ZSM, beta, Y and other molecular sieves as carriers and loading noble metal Pt or Pd, has excellent pore channel structure, avoids cracking reaction, has strong acidity, has good tolerance to raw material impurities and is easy to regenerate after deactivation. However, the pore canal of the microporous molecular sieve is relatively smaller, while the mesoporous molecular sieve material has higher specific surface area and larger pore diameter, which is favorable for highly dispersing the metal active components on the surface of the carrier, and the large pore diameter ensures that the macromolecular reactant is easier to diffuse and transmit in the pore canal, avoids excessive cracking, and improves the yield and selectivity of the target product; with intensive research, the preparation and application of mesoporous composite materials are widely focused by researchers at present.
Chinese patent CN106513035a discloses a mesoporous composite molecular sieve catalyst with a core-shell structure, wherein the catalyst is prepared by using microporous molecular sieve ZSM-23 as a core and mesoporous molecular sieve MCM-41 or SBA-15 as a shell through a eutectic method. Experiments show that the mesoporous composite molecular sieve prepared by the method has adjustable inner and outer core-shell ratio, the acid density and acid strength can be changed by changing the amount of ZSM-23, and the pore diameter of the mesoporous molecular sieve is larger, so that the method is beneficial to the entry and exit of macromolecules in pore channels. When the isomerization dewaxing of the lubricating oil fraction was carried out, the reaction temperature was 330℃and the volumetric liquid hourly space velocity was 1.0h at a hydrogen partial pressure of 10MPa -1 The catalyst has high isomerization reaction activity and selectivity under the condition of 500 hydrogen-oil ratio, the isomerization selectivity is more than 93 percent, and the isomerization selectivity of the multi-branched alkane is more than 58 percent under the condition of 97 percent conversion.
Chinese patent CN110773225a discloses a core-shell mesoporous composite in which an ordered mesoporous silica layer is coated on a microporous molecular sieve mordeniteThe material is loaded with nickel oxide for hydroisomerization, the catalyst not only has metal centers meeting the hydrogenation and dehydrogenation requirements, but also has acid centers meeting the isomerization reaction requirements, and the separation and reunion between the metal positions and the acid positions are proper, so that the yield of the multi-branched isomer in the isomerization reaction is improved. At a reaction temperature of 275 ℃, a hydrogen flow rate of 35sccm and a space velocity of 3.6h -1 Under the condition of (2), the conversion rate and the selectivity of hydroisomerization reach about 80 percent.
Chinese patent CN107497480a discloses a multi-level porous mesoporous and microporous composite molecular sieve catalyst having both MFI microporous structure and MCM-41 mesoporous structure, which combines the advantages of higher acidity of microporous molecular sieve and high mesoporous order of mesoporous molecular sieve, and has good mechanical stability and hydrothermal stability, and good catalytic activity.
Therefore, providing a novel mesoporous composite molecular sieve, preparation thereof, normal alkane hydroisomerization catalyst, preparation and application thereof have become technical problems to be solved in the field.
Disclosure of Invention
In order to solve the above-mentioned disadvantages and shortcomings, an object of the present invention is to provide a mesoporous composite molecular sieve. The mesoporous composite molecular sieve material provided by the invention has the advantages of high specific surface area, large aperture, proper and adjustable acidity, and the catalyst obtained by taking the mesoporous composite molecular sieve material as a carrier to load noble metal is more suitable for catalyzing normal alkane hydroisomerization reaction.
The invention also aims at providing a preparation method of the mesoporous composite molecular sieve.
Still another object of the present invention is to provide a hydroisomerization catalyst for normal paraffins, wherein the carrier used is the mesoporous composite molecular sieve described above.
It is still another object of the present invention to provide a process for preparing the above-described catalyst for hydroisomerization of n-alkanes.
It is a further object of the present invention to provide the use of the above-described normal paraffin hydroisomerization catalyst in a normal paraffin hydroisomerization reaction.
In order to achieve the above object, in one aspect, the present invention provides a mesoporous composite molecular sieve, wherein the mesoporous composite molecular sieve is prepared by compositing microporous mordenite molecular sieve with organic-inorganic hybrid mesoporous silica, and has mesoporous and microporous concentrated type double pore distribution and double hysteresis rings, and a specific surface area of 400-850m 2 ·g -1 Pore volume of 0.35-0.85cm 3 ·g -1 Pore diameter of 5-8nm, preferably pore volume of 0.40-0.85cm 3 ·g -1 The aperture is 6-8nm.
As a specific embodiment of the above mesoporous composite molecular sieve according to the present invention, the mesoporous composite molecular sieve is sunflower-shaped.
As a specific embodiment of the above mesoporous composite molecular sieve according to the present invention, siO 2 And Al 2 O 3 The molar ratio of (2) is 50 to 400, preferably 50 to 200, more preferably 50 to 150.
The mesoporous and microporous composite molecular sieve provided by the invention has high specific surface area, larger aperture and proper acidity, and the acidity is adjustable, namely the acidity of the mesoporous and microporous composite molecular sieve changes along with the change of the silicon-aluminum ratio.
On the other hand, the invention also provides a preparation method of the mesoporous composite molecular sieve, wherein the preparation method comprises the following steps:
uniformly mixing a template agent, water, alcohol, an alkali source, an alkane organic solvent, an organic silicon source and an inorganic silicon source to obtain mesoporous material precursor emulsion, and adding H-type microporous mordenite molecular sieve seed crystals into the mesoporous material precursor emulsion to obtain a mesoporous composite molecular sieve;
wherein, inorganic silicon source: organosilicon source: seed crystal of H-type microporous mordenite molecular sieve: template agent: water: alkali source: alcohol: the molar ratio of alkane organic solvent is 1 (0.03-0.2) (0.005-0.025) (0.1-0.25) (500-750) (0.75-1.0) (40-60) (10-50); preferably 1 (0.05-0.1): (0.005-0.025): (0.1-0.25): (500-750): (0.75-1.0): (40-60): (15-25);
wherein the dosage of the inorganic silicon source and the organic silicon source is equalIn SiO form 2 The dosage of the H-type microporous mordenite molecular sieve seed crystal is calculated by Al 2 O 3 And (5) counting.
As a specific embodiment of the preparation method of the mesoporous composite molecular sieve according to the present invention, the preparation method comprises the following specific steps:
(1) Adding the H-type microporous mordenite molecular sieve seed crystal, an alkali source and alcohol into water, and uniformly mixing;
(2) Adding a template agent into the solution obtained in the step (1) and uniformly mixing;
(3) Adding an organosilicon source into the solution obtained in the step (2) and uniformly mixing;
(4) Adding a template agent into the solution obtained in the step (3) and uniformly mixing;
(5) Adding an alkane organic solvent and an inorganic silicon source into the solution obtained in the step (4) and uniformly mixing;
(6) And (3) filtering the solution obtained in the step (5), drying the obtained solid product, extracting the template agent in the solid product, and drying to obtain the mesoporous composite molecular sieve.
As a specific embodiment of the preparation method of the mesoporous and microporous composite molecular sieve, in the step (1), the H-type microporous mordenite molecular sieve seed crystal, the alkali source and the alcohol are added into water, and heated and stirred for 1-2 hours at 25-40 ℃, preferably at 35 ℃ for 1 hour, so that the performance of the prepared mesoporous and microporous composite molecular sieve can be improved, and the catalytic activity of the catalyst is remarkably improved.
As a specific embodiment of the preparation method of the mesoporous composite molecular sieve, in the step (2), a template agent is added into the solution obtained in the step (1), and stirring is continued for 0.5-1h.
In a specific embodiment of the method for preparing a mesoporous composite molecular sieve according to the present invention, the alcohol may be, for example, a conventional alcohol such as ethanol.
As a specific embodiment of the preparation method of the mesoporous composite molecular sieve, in the step (3), an organosilicon source is slowly added into the solution obtained in the step (2), and stirring is performed for 18-24 hours under the same condition.
As a specific embodiment of the preparation method of the mesoporous composite molecular sieve, in the step (4), adding the template agent into the solution obtained in the step (3), and continuously stirring for 0.5-1h.
As a specific embodiment of the preparation method of the mesoporous composite molecular sieve according to the present invention, the molar ratio of the template agent in the step (4) to the template agent in the step (2) is 2-4:1, preferably 3:1.
As a specific embodiment of the preparation method of the mesoporous composite molecular sieve, in the step (5), an alkane organic solvent and an inorganic silicon source are slowly added into the solution obtained in the step (4), and stirring is carried out for 18-24 hours.
Wherein the stirring speed used in step (1) to step (5) may be 700r/s.
As a specific embodiment of the above-mentioned method for preparing a mesoporous composite molecular sieve according to the present invention, in the step (6), the drying conditions may be various drying conditions in the art, and may include, for example: the drying temperature is 50-100 ℃ and the drying time is 6-12h. In some embodiments of the invention, the temperature of the drying may be 60 ℃, for example, and the time may be 12 hours.
In the step (6), the extraction solvent used for the extraction is hydrochloric acid and ethanol, and the extraction temperature is 60 ℃.
The invention uses the organic silicon source when preparing the mesoporous composite molecular sieve, the use of the organic silicon source can improve the specific surface area and the aperture of the mesoporous silicon-based molecular sieve, thereby improving the specific surface area and the aperture of the mesoporous composite molecular sieve, and the prepared mesoporous composite molecular sieve has two aperture distributions; the advantages of large pore diameter and favorable diffusion can be well exerted in the hydroisomerization reaction of normal alkane, and the acidity of the mesoporous composite molecular sieve is effectively regulated by introducing microporous zeolite into the mesoporous composite molecular sieve.
As a specific embodiment of the preparation method of the mesoporous and microporous composite molecular sieve, the preparation method of the H-type microporous mordenite molecular sieve seed crystal comprises the following steps:
1) Mixing silicon source, aluminum source, alkali source and water uniformly, wherein the molar ratio of the raw materials is (5.0-10.0) Na 2 O:Al 2 O 3 :(10-100)SiO 2 :(500-1500)H 2 O, preferably (5.0-6.0) Na 2 O:Al 2 O 3 :(10-50)SiO 2 :(500-1000)H 2 O；
2) Crystallizing the solution obtained in the step 1) to obtain microporous mordenite molecular sieve microcrystalline emulsion, and filtering, washing, drying and roasting to obtain microporous mordenite molecular sieve raw powder;
3) And carrying out ion exchange on the microporous mordenite molecular sieve raw powder and an ammonium salt solution for a plurality of times, and then filtering, drying and roasting to finally obtain the H-type microporous mordenite molecular sieve seed crystal.
As a specific embodiment of the above preparation method of the mesoporous composite molecular sieve according to the present invention, the organosilicon source includes one or a combination of several of 1, 2-bis (triethoxysilyl) ethane (BTEE), 1, 2-bis (trimethoxysilyl) ethane (BTME), and 1, 4-bis (triethoxysilyl) benzene (BTEB), preferably 1, 2-bis (triethoxysilyl) ethane (BTEE);
as a specific embodiment of the preparation method of the mesoporous composite molecular sieve, the inorganic silicon source comprises one or a combination of more of silica sol, tetraethyl orthosilicate (TEOS) and water glass, preferably TEOS, and the organic silicon source and the inorganic silicon source used in the preparation method can improve the performance of the prepared mesoporous composite molecular sieve, and further obviously improve the catalytic activity of the catalyst.
As a specific embodiment of the above preparation method of the mesoporous composite molecular sieve according to the present invention, the alkali source includes ammonia water and/or sodium hydroxide, preferably ammonia water.
As a specific embodiment of the preparation method of the mesoporous and microporous composite molecular sieve according to the present invention, the template agent includes one or a combination of several of Octadecyl Trimethyl Ammonium Chloride (OTAC), cetyl Trimethyl Ammonium Chloride (CTAC) and Cetyl Trimethyl Ammonium Bromide (CTAB), preferably Cetyl Trimethyl Ammonium Bromide (CTAB).
As a specific embodiment of the preparation method of the mesoporous composite molecular sieve, the alkane organic solvent comprises one or a combination of more of n-hexane, cyclohexane and n-pentane.
As a specific embodiment of the preparation method of the mesoporous composite molecular sieve, the temperature is controlled to be 25-40 ℃ in the preparation process of the mesoporous composite molecular sieve.
In the step 1), the silicon source comprises one or a combination of more of silica sol, water glass and tetraethyl orthosilicate, preferably tetraethyl orthosilicate or silica sol;
the aluminum source comprises one or a combination of more of sodium metaaluminate, aluminum oxide, aluminum chloride and aluminum nitrate, and is preferably sodium metaaluminate;
The alkali source may be various alkali known in the art, for example, na 2 CO 3 And/or NaOH, preferably NaOH.
As a specific embodiment of the preparation method of the mesoporous composite molecular sieve, in the step 1), a silicon source, an aluminum source, an alkali source and water are mixed and stirred for 2-4 hours until the solution is not layered any more.
As a specific embodiment of the above preparation method of the mesoporous composite molecular sieve according to the present invention, in the step 2), the crystallization temperature is 100 to 200 ℃, preferably 140 to 180 ℃, more preferably 160 to 180 ℃, and the time is 24 to 48 hours, preferably 30 to 48 hours, more preferably 30 to 40 hours; the crystallization is carried out under more preferable conditions, so that the performance of the prepared microporous mordenite molecular sieve can be improved, and the catalytic activity of the catalyst is obviously improved;
the temperature of the drying is 50-100 ℃ and the time is 6-12h;
the roasting temperature is 400-600 ℃, and the time is 4-8 hours, preferably 4-7 hours.
As a specific embodiment of the preparation method of the mesoporous and microporous composite molecular sieve according to the present invention, in the step 3), the ammonium salt includes one or a combination of several of ammonium chloride, ammonium nitrate and ammonium sulfate, preferably ammonium chloride, and the mass ratio of the ammonium salt to the microporous mordenite molecular sieve raw powder is 1-5:1, preferably 3:1;
In the ammonium salt solution, the mass ratio of the ammonium salt to water is 1:5-1:10, preferably 1:10;
the temperature of the ion exchange is 50-100 ℃, preferably 80 ℃ for 1-5 hours, preferably 2-4 hours; the ammonium salt used in the invention, the dosage thereof and the ion exchange parameters can better exchange Na-type MOR into H-type MOR;
the temperature of the drying is 50-100 ℃, preferably 60-100 ℃, more preferably 80 ℃ and the time is 6-12h;
the calcination temperature is 400-600deg.C, preferably 550deg.C, for 3-8h, preferably 4-8h, more preferably 6h.
In addition, the number of ion exchanges in step 3) may be adjusted according to the actual situation, as long as it is ensured that Na form can be completely exchanged for H form. In some embodiments of the invention, the number of ion exchanges may be, for example, 2 or 3, etc.
In still another aspect, the present invention further provides a hydroisomerization catalyst for normal paraffins, which comprises a carrier and an active component supported on the carrier, wherein the carrier is the mesoporous composite molecular sieve described above, the active component is a noble metal, and the loading amount of the noble metal is 0.5 to 1wt%, preferably 1wt%, based on 100% of the total weight of the carrier.
As a specific embodiment of the above-mentioned normal paraffin hydroisomerization catalyst according to the present invention, the noble metal includes at least one of group VIII metals, preferably Pt.
In still another aspect, the present invention further provides a method for preparing the above-mentioned normal paraffin hydroisomerization catalyst, wherein the preparation method comprises:
the noble metal precursor water solution is soaked on the mesoporous composite molecular sieve carrier, and then the normal alkane hydroisomerization catalyst is obtained after ultrasonic treatment, drying and roasting.
As a specific embodiment of the above-described method for producing a normal paraffin hydroisomerization catalyst according to the present invention, the impregnation method includes an isovolumetric impregnation method, an excess impregnation method, an ion exchange method, or the like, and preferably an isovolumetric impregnation method.
As a specific embodiment of the preparation method of the normal paraffin hydroisomerization catalyst, the time of the ultrasonic wave is 30-60min, preferably 40min.
As a specific embodiment of the above-mentioned method for preparing the normal paraffin hydroisomerization catalyst according to the present invention, the drying temperature is 50-100 ℃, preferably 60 ℃ for 6-12 hours, preferably 10 hours.
As a specific embodiment of the above-mentioned method for preparing the normal paraffin hydroisomerization catalyst according to the present invention, the calcination temperature is 300-500 ℃, preferably 350 ℃ for 2-6 hours, preferably 4 hours.
As a specific embodiment of the above-mentioned method for preparing a normal paraffin hydroisomerization catalyst according to the present invention, when the noble metal is Pt, the noble metal precursor is chloroplatinic acid hexahydrate and/or nitrotetraammineplatinum, preferably chloroplatinic acid hexahydrate.
In a final aspect, the invention also provides the use of the above-described normal paraffin hydroisomerization catalyst in a normal paraffin hydroisomerization reaction.
As a specific embodiment of the above application of the present invention, the hydroisomerization catalyst of normal paraffins needs to be pre-reduced under the following conditions: the hydrogen partial pressure is 4MPa, the temperature is 350 ℃, and the reduction time is 4 hours.
As a specific embodiment of the above application of the present invention, the hydroisomerization reaction conditions are as follows:
the volume liquid hourly space velocity is 1.0 to 1.5h -1 The reaction temperature is 200-340 ℃, the reaction pressure is 1.5MPa, and the hydrogen-oil volume ratio is 400.
The water used in the present invention may be at least one of pure water, distilled water and deionized water, preferably deionized water.
Compared with the prior art, the invention has the following beneficial technical effects:
(1) The organic-inorganic hybrid mesoporous silica, namely mesoporous silica-based molecular sieve material is prepared by hybridization of an inorganic silica source and an organic silica source, and can improve the specific surface area and the pore diameter of the mesoporous silica-based molecular sieve material, so that the specific surface area and the pore diameter of a mesoporous composite molecular sieve are improved, the mesoporous composite molecular sieve has excellent thermal and hydrothermal stability, and the prepared mesoporous composite molecular sieve has two pore diameter distributions; the advantages of large pore diameter and favorable diffusion can be well exerted in the hydroisomerization reaction of normal alkane.
(2) The mesoporous composite molecular sieve provided by the invention is obtained by compositing the microporous Mordenite (MOR) molecular sieve serving as a seed crystal with the mesoporous silicon-based molecular sieve material under a low-temperature hydrothermal condition, has proper acidity, can adjust the acidity through different addition amounts of the microporous Mordenite (MOR) molecular sieve, is beneficial to hydroisomerization reaction, and can also enable the mesoporous composite molecular sieve to retain the pore channel structure of the mesoporous silicon-based molecular sieve material.
(3) The catalyst for hydroisomerization of normal paraffins provided by the invention takes the mesoporous composite molecular sieve as a carrier, and has high catalytic activity and selectivity on the hydroisomerization reaction of normal paraffins. The hydroisomerization activity of the normal alkane hydroisomerization catalyst provided by the embodiment of the invention is evaluated by taking normal heptane as a reaction raw material, and the evaluation result shows that: the catalyst has high catalytic activity and selectivity, the conversion rate is gradually increased along with the increase of the reaction temperature, the maximum conversion rate is 69.5% under the reaction temperature condition of 260 ℃, and the selectivity reaches 88.1%.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for the description of the embodiments will be briefly described, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings may be obtained according to the drawings without inventive effort for a person skilled in the art.
FIG. 1 shows the MOR-SFMSNs (SiO) obtained in example 1 of the present invention 2 /Al 2 O 3 Molar ratio 100).
FIG. 2 shows the MOR-SFMSNs (SiO) obtained in example 1 of the present invention 2 /Al 2 O 3 Molar ratio of 100) N 2 Adsorption desorption isotherm plot.
FIG. 3 shows the MOR-SFMSNs (SiO) obtained in example 1 of the present invention 2 /Al 2 O 3 Molar ratio 100).
FIG. 4 shows the MOR-SFMSNs (SiO) obtained in example 1 of the present invention 2 /Al 2 O 3 A molar ratio of 100) Transmission Electron Microscopy (TEM) spectra.
FIG. 5 shows the MOR-SFMSNs (SiO) obtained in example 1 of the present invention 2 /Al 2 O 3 Molar ratio 100) of the electron scanning microscope (SEM) spectra.
Fig. 6 is a Transmission Electron Microscope (TEM) spectrum of the SFMSNs prepared in comparative example 2.
FIG. 7 is a Scanning Electron Microscope (SEM) spectrum of SFMSNs prepared in comparative example 2.
Detailed Description
It should be noted that the term "comprising" in the description of the invention and the claims and any variations thereof in the above-described figures is intended to cover a non-exclusive inclusion, such as a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements that are expressly listed or inherent to such process, method, article, or apparatus.
The "range" disclosed herein is given in the form of a lower limit and an upper limit. There may be one or more lower limits and one or more upper limits, respectively. The given range is defined by selecting a lower limit and an upper limit. The selected lower and upper limits define the boundaries of the particular ranges. All ranges defined in this way are combinable, i.e. any lower limit can be combined with any upper limit to form a range. For example, ranges of 60-120 and 80-110 are listed for specific parameters, with the understanding that ranges of 60-110 and 80-120 are also contemplated. Furthermore, if the minimum range values listed are 1 and 2 and the maximum range values listed are 3,4 and 5, then the following ranges are all contemplated: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5.
In the present invention, unless otherwise indicated, the numerical range "a-b" represents a shorthand representation of any combination of real numbers between a and b, where a and b are both real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" have been listed throughout this disclosure, and "0-5" is only a shorthand representation of a combination of these values.
In the present invention, all the embodiments and preferred embodiments mentioned in the present invention may be combined with each other to form new technical solutions, unless otherwise specified.
In the present invention, all technical features mentioned in the present invention and preferred features may be combined with each other to form a new technical solution unless specifically stated otherwise.
The present invention will be further described in detail with reference to the accompanying drawings, figures and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. The following described embodiments are some, but not all, examples of the present invention and are merely illustrative of the present invention and should not be construed as limiting the scope of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.
Mesoporous composite molecular sieve examples
Example 1
The embodiment provides a mesoporous composite molecular sieve (MOR-SFMSNs), which is prepared by compositing microporous mordenite molecular sieve with organic-inorganic hybrid mesoporous silica, and the preparation method comprises the following specific steps:
1. The method adopts a hydrothermal crystallization method to prepare microporous mordenite molecular sieve raw powder:
taking sodium metaaluminate, naOH and deionized water according to 6Na 2 O:Al 2 O 3 :780H 2 Placing the molar ratio of O in a beaker, dissolving at room temperature, and stirring for 1h until the mixture is clear to obtain a first solution;
adding a silica sol to the first solution, wherein n (SiO 2 )/n(Al 2 O 3 ) =100, stirring for 1-2h until the formed solution no longer delaminates, yielding a second solution;
transferring the second solution into a crystallization kettle, carrying out hydrothermal crystallization for 30 hours at 180 ℃, filtering, washing, drying for 10 hours at 80 ℃, and roasting for 6 hours at 550 ℃ to obtain microporous mordenite molecular sieve raw powder, namely Na-type MOR microporous molecular sieve seed crystals for later use.
2. Preparing H-type microporous mordenite molecular sieve seed crystals:
the MOR microporous molecular sieve seed crystal and NH prepared by the method are seeded 4 Cl and deionized water, wherein the mass ratio of the ammonium salt to the MOR microporous molecular sieve seed crystal is 1:10, the mass ratio of the ammonium salt to the MOR microporous molecular sieve seed crystal is 3:1, the ammonium exchange is carried out for the first time under the water bath condition of 80 ℃, the ammonium exchange is carried out for 2 hours after stirring, the filtering is carried out, the drying is carried out for 10 hours at 80 ℃, the roasting is carried out for 3 hours at 550 ℃, and then the second ammonium exchange is carried out for the same step, thus obtaining the H-type microporous mordenite molecular sieve seed crystal, namely the H-type MOR molecular sieve seed crystal.
3. MOR-SFMSNs are prepared by adopting a hydrothermal synthesis method:
(1): seeding of H-MOR molecular sieves (in terms of their molar ratio to silica to alumina between inorganic silica source TEOS and organosilicon source BTEE, i.e., n (SiO) 2 )/n(Al 2 O 3 100), 25wt% of ammonia water solution and absolute ethyl alcohol are added into deionized water, and stirring is carried out for 1h at the temperature of 35 ℃ and the rotating speed of 700r/s, so as to obtain a third solution;
(2): adding a template agent CTAB into the third solution, and continuously stirring for 1h to obtain a fourth solution;
(3): adding an organic silicon source BTEE into the fourth solution, and stirring for 24 hours to obtain a fifth solution;
(4): adding a template agent CTAB into the fifth solution, wherein the molar quantity of CTAB in the step (4) is 3 times that of CTAB in the step (2), and stirring the suspension for 1h to obtain a sixth solution;
(5): adding n-hexane and TEOS into the sixth solution, and stirring for 24 hours to obtain a seventh solution;
(6): filtering the seventh solution, drying the solid product obtained by filtering, extracting the template agent CTAB in the dried solid product, and then drying to obtain MOR-SFMSNs; wherein the temperature of the drying (baking) is 60 ℃ and the time is 12 hours, the extraction solvents used in the extraction are hydrochloric acid and ethanol, and the extraction temperature is 60 ℃.
Wherein, the mole ratio of the raw materials is as follows: 1.12CTAB:1TEOS:0.08BTEE:62.23 Water, 0.89 Ammonia, 51.22 ethanol, 22.88 n-hexane.
Example 2
This example provides a mesoporous composite molecular sieve (MOR-SFMSNs) which differs from example 1 only in that:
in the step (1), the molar ratio of silicon to aluminum (SiO 2 /Al 2 O 3 ) 80.
Example 3
This example provides a mesoporous composite molecular sieve (MOR-SFMSNs) which differs from example 1 only in that:
in the step (1), the molar ratio of silicon to aluminum (SiO 2 /Al 2 O 3 ) 50.
Example 4
This example provides a mesoporous composite molecular sieve (MOR-SFMSNs) which differs from example 1 only in that:
in the step (1), the molar ratio of silicon to aluminum (SiO 2 /Al 2 O 3 ) 120.
Example 5
This example provides a mesoporous composite molecular sieve (MOR-SFMSNs) which differs from example 1 only in that:
in the step (1), the molar ratio of silicon to aluminum (SiO 2 /Al 2 O 3 ) 150.
Example 6
This example provides a mesoporous composite molecular sieve (MOR-SFMSNs) which differs from example 1 only in that:
the organic silicon sources are different in dosage, and the molar ratio of the raw materials is as follows: 1.12CTAB:1TEOS:0.16BTEE:62.23 water, 0.89 ammonia water, 51.22 ethanol, 22.88 n-hexane.
Example 7
This example provides a mesoporous composite molecular sieve (MOR-SFMSNs) which differs from example 1 only in that:
the organic silicon sources are different in dosage, and the molar ratio of the raw materials is as follows: 1.12CTAB:1TEOS:0.04BTEE:62.23 Water, 0.89 Ammonia, 51.22 ethanol, 22.88 n-hexane.
Example 8
This example provides a mesoporous composite molecular sieve (MOR-SFMSNs) which differs from example 1 only in that:
the dosage of the n-hexane is different, and the molar ratio of the raw materials is as follows: 1.12CTAB:1TEOS:0.08BTEE:62.23 water, 0.89 ammonia water, 51.22 ethanol, 45.76 n-hexane.
Example 9
This example provides a mesoporous composite molecular sieve (MOR-SFMSNs) which differs from example 1 only in that:
the dosage of the n-hexane is different, and the molar ratio of the raw materials is as follows: 1.12CTAB:1TEOS:0.08BTEE:62.23 Water, 0.89 Ammonia, 51.22 ethanol, 11.44 n-hexane.
Example 10
This example provides a mesoporous composite molecular sieve (MOR-SFMSNs) which differs from example 1 only in that:
the aluminum source dosage in the process of preparing the microporous mordenite molecular sieve raw powder is different, siO 2 /Al 2 O 3 50.
Examples of catalysts for hydroisomerization of normal paraffins
Example 11
The embodiment provides a normal paraffin hydroisomerization catalyst, which comprises a carrier and an active component loaded on the carrier, wherein the carrier is the mesoporous composite molecular sieve provided in the embodiment 1, the active component is noble metal Pt, and the preparation method of the normal paraffin hydroisomerization catalyst comprises the following steps:
Step one: 1g of chloroplatinic acid hexahydrate (H) 2 PtCl 6 ·6H 2 O) dissolving into a certain amount of deionized water to prepare a chloroplatinic acid solution with the concentration of 0.137 mol/L;
step two: and (3) immersing the chloroplatinic acid solution prepared in the step (A) on the mesoporous composite molecular sieve provided in the example (1) in an equal volume, carrying out ultrasonic treatment for 40min, drying at 60 ℃ for 6h, roasting at 350 ℃ for 4h, and cooling to room temperature to obtain the Pt-loaded normal alkane hydroisomerization catalyst.
Through testing, in the normal alkane hydroisomerization catalyst, the Pt loading is 1wt%, and is marked as Cat-1.
Example 12
The embodiment provides a normal paraffin hydroisomerization catalyst, which comprises a carrier and an active component loaded on the carrier, wherein the carrier is the mesoporous composite molecular sieve provided in the embodiment 2, the active component is noble metal Pt, and the preparation method of the normal paraffin hydroisomerization catalyst comprises the following steps:
step one: 1g of chloroplatinic acid hexahydrate (H) 2 PtCl 6 ·6H 2 O) dissolving into a certain amount of deionized water to prepare a chloroplatinic acid solution with the concentration of 0.137 mol/L;
step two: and (3) immersing the chloroplatinic acid solution prepared in the step (A) on the mesoporous composite molecular sieve provided in the example (2) in an equal volume, carrying out ultrasonic treatment for 40min, drying at 60 ℃ for 6h, roasting at 350 ℃ for 4h, and cooling to room temperature to obtain the Pt-loaded normal alkane hydroisomerization catalyst.
Through testing, in the normal alkane hydroisomerization catalyst, the Pt loading is 1wt%, and is marked as Cat-2.
Example 13
The embodiment provides a normal paraffin hydroisomerization catalyst, which comprises a carrier and an active component loaded on the carrier, wherein the carrier is the mesoporous composite molecular sieve provided in the embodiment 3, the active component is noble metal Pt, and the preparation method of the normal paraffin hydroisomerization catalyst comprises the following steps:
step one: 1g of chloroplatinic acid hexahydrate (H) 2 PtCl 6 ·6H 2 O) dissolving into a certain amount of deionized water to prepare a chloroplatinic acid solution with the concentration of 0.137 mol/L;
step two: and (3) immersing the chloroplatinic acid solution prepared in the step (A) on the mesoporous composite molecular sieve provided in the example (3) in an equal volume, carrying out ultrasonic treatment for 40min, drying at 60 ℃ for 6h, roasting at 350 ℃ for 4h, and cooling to room temperature to obtain the Pt-loaded normal alkane hydroisomerization catalyst.
Through testing, in the normal alkane hydroisomerization catalyst, the Pt loading is 1wt%, and is marked as Cat-3.
Example 14
The embodiment provides a normal paraffin hydroisomerization catalyst, which comprises a carrier and an active component loaded on the carrier, wherein the carrier is the mesoporous composite molecular sieve provided in the embodiment 4, the active component is noble metal Pt, and the preparation method of the normal paraffin hydroisomerization catalyst comprises the following steps:
Step one: 1g of chloroplatinic acid hexahydrate (H) 2 PtCl 6 ·6H 2 O) dissolving into a certain amount of deionized water to prepare a chloroplatinic acid solution with the concentration of 0.137 mol/L;
step two: and (3) immersing the chloroplatinic acid solution prepared in the step (A) on the mesoporous composite molecular sieve provided in the example (4) in an equal volume, carrying out ultrasonic treatment for 40min, drying at 60 ℃ for 6h, roasting at 350 ℃ for 4h, and cooling to room temperature to obtain the Pt-loaded normal alkane hydroisomerization catalyst.
Through testing, in the normal alkane hydroisomerization catalyst, the Pt loading is 1wt%, and is marked as Cat-4.
Example 15
The embodiment provides a normal paraffin hydroisomerization catalyst, which comprises a carrier and an active component loaded on the carrier, wherein the carrier is the mesoporous composite molecular sieve provided in the embodiment 5, the active component is noble metal Pt, and the preparation method of the normal paraffin hydroisomerization catalyst comprises the following steps:
step one: 1g of chloroplatinic acid hexahydrate (H) 2 PtCl 6 ·6H 2 O) dissolving into a certain amount of deionized water to prepare a chloroplatinic acid solution with the concentration of 0.137 mol/L;
step two: and (3) immersing the chloroplatinic acid solution prepared in the step (A) on the mesoporous composite molecular sieve provided in the example (5) in an equal volume, carrying out ultrasonic treatment for 40min, drying at 60 ℃ for 6h, roasting at 350 ℃ for 4h, and cooling to room temperature to obtain the Pt-loaded normal alkane hydroisomerization catalyst.
Through testing, in the normal alkane hydroisomerization catalyst, the Pt loading is 1wt%, and is marked as Cat-5.
Example 16
The embodiment provides a normal paraffin hydroisomerization catalyst, which comprises a carrier and an active component loaded on the carrier, wherein the carrier is the mesoporous composite molecular sieve provided in the embodiment 6, the active component is noble metal Pt, and the preparation method of the normal paraffin hydroisomerization catalyst comprises the following steps:
step one: 1g of chloroplatinic acid hexahydrate (H) 2 PtCl 6 ·6H 2 O) dissolving into a certain amount of deionized water to prepare a chloroplatinic acid solution with the concentration of 0.137 mol/L;
step two: and (3) immersing the chloroplatinic acid solution prepared in the step (I) on the mesoporous composite molecular sieve provided in the example (6) in an equal volume, carrying out ultrasonic treatment for 40min, drying at 60 ℃ for 6h, roasting at 350 ℃ for 4h, and cooling to room temperature to obtain the Pt-loaded normal alkane hydroisomerization catalyst.
Through testing, in the normal alkane hydroisomerization catalyst, the Pt loading is 1wt%, and is marked as Cat-6.
Example 17
The embodiment provides a normal paraffin hydroisomerization catalyst, which comprises a carrier and an active component loaded on the carrier, wherein the carrier is the mesoporous composite molecular sieve provided in the embodiment 7, the active component is noble metal Pt, and the preparation method of the normal paraffin hydroisomerization catalyst comprises the following steps:
Step one: 1g of chloroplatinic acid hexahydrate (H) 2 PtCl 6 ·6H 2 O) dissolving into a certain amount of deionized water to prepare a chloroplatinic acid solution with the concentration of 0.137 mol/L;
step two: and (3) immersing the chloroplatinic acid solution prepared in the step (I) on the mesoporous composite molecular sieve provided in the example 7 in an equal volume, carrying out ultrasonic treatment for 40min, drying at 60 ℃ for 6h, roasting at 350 ℃ for 4h, and cooling to room temperature to obtain the Pt-loaded normal alkane hydroisomerization catalyst.
Through testing, in the normal alkane hydroisomerization catalyst, the Pt loading is 1wt%, and is marked as Cat-7.
Example 18
The embodiment provides a normal paraffin hydroisomerization catalyst, which comprises a carrier and an active component loaded on the carrier, wherein the carrier is the mesoporous composite molecular sieve provided in the embodiment 8, the active component is noble metal Pt, and the preparation method of the normal paraffin hydroisomerization catalyst comprises the following steps:
step one: 1g of chloroplatinic acid hexahydrate (H) 2 PtCl 6 ·6H 2 O) dissolving into a certain amount of deionized water to prepare a chloroplatinic acid solution with the concentration of 0.137 mol/L;
step two: and (3) immersing the chloroplatinic acid solution prepared in the step (I) on the mesoporous composite molecular sieve provided in the example 8 in an equal volume, carrying out ultrasonic treatment for 40min, drying at 60 ℃ for 6h, roasting at 350 ℃ for 4h, and cooling to room temperature to obtain the Pt-loaded normal alkane hydroisomerization catalyst.
Through testing, in the normal alkane hydroisomerization catalyst, the Pt loading is 1wt%, and is marked as Cat-8.
Example 19
The embodiment provides a normal paraffin hydroisomerization catalyst, which comprises a carrier and an active component loaded on the carrier, wherein the carrier is the mesoporous composite molecular sieve provided in the embodiment 9, the active component is noble metal Pt, and the preparation method of the normal paraffin hydroisomerization catalyst comprises the following steps:
step one: 1g of chloroplatinic acid hexahydrate (H) 2 PtCl 6 ·6H 2 O) dissolving into a certain amount of deionized water to prepare a chloroplatinic acid solution with the concentration of 0.137 mol/L;
step two: and (3) immersing the chloroplatinic acid solution prepared in the step (I) on the mesoporous composite molecular sieve provided in the example 9 in an equal volume, carrying out ultrasonic treatment for 40min, drying at 60 ℃ for 6h, roasting at 350 ℃ for 4h, and cooling to room temperature to obtain the Pt-loaded normal alkane hydroisomerization catalyst.
Through testing, in the normal alkane hydroisomerization catalyst, the Pt loading is 1wt%, and is marked as Cat-9.
Example 20
The embodiment provides a normal paraffin hydroisomerization catalyst, which comprises a carrier and an active component loaded on the carrier, wherein the carrier is the mesoporous composite molecular sieve provided in the embodiment 10, the active component is noble metal Pt, and the preparation method of the normal paraffin hydroisomerization catalyst comprises the following steps:
Step one: 1g of chloroplatinic acid hexahydrate (H) 2 PtCl 6 ·6H 2 O) dissolving into a certain amount of deionized water to prepare a chloroplatinic acid solution with the concentration of 0.137 mol/L;
step two: and (3) immersing the chloroplatinic acid solution prepared in the step (A) on the mesoporous composite molecular sieve provided in the example (10) in an equal volume, carrying out ultrasonic treatment for 40min, drying at 60 ℃ for 6h, roasting at 350 ℃ for 4h, and cooling to room temperature to obtain the Pt-loaded normal alkane hydroisomerization catalyst.
Through testing, in the normal alkane hydroisomerization catalyst, the Pt loading is 1wt%, and is marked as Cat-10.
Comparative example 1
The comparative example provides a normal paraffin hydroisomerization catalyst comprising a carrier and an active component supported on the carrier, wherein the carrier is an H-type MOR molecular sieve seed crystal provided in example 1, the active component is noble metal Pt, the preparation methods of the H-type MOR molecular sieve seed crystal and the normal paraffin hydroisomerization catalyst are the same as those in example 1 and example 12, and the normal paraffin hydroisomerization catalyst provided in the example is referred to as Cat-11.
Comparative example 2
The comparative example provides a normal alkane hydroisomerization catalyst comprising a carrier and an active component supported on the carrier, wherein the carrier is SFMSNs, and the active component is noble metal Pt;
SFMSNs differ from the MOR-SFMSNs provided in example 1 in that: the seed crystal of the H-type MOR molecular sieve is not added when the SFMSNs are prepared;
the preparation method of the normal paraffin hydroisomerization catalyst is the same as that of the example 11, and the normal paraffin hydroisomerization catalyst provided in the example is marked as Cat-12.
Characterization test case
This test example shows the MOR-SFMSNs (SiO) obtained in example 1 of the present invention 2 /Al 2 O 3 Molar ratio of 100) were subjected to wide angle XRD, N 2 Analysis such as adsorption and desorption, transmission electron microscope and scanning electron microscope shows that the wide angle XRD result is shown in figure 1, N 2 Adsorption and desorption isotherms are shown in fig. 2, pore size distribution results are shown in fig. 3, transmission Electron Microscopy (TEM) results are shown in fig. 4, and Scanning Electron Microscopy (SEM) results are shown in fig. 5. Meanwhile, the SFMSNs prepared in comparative example 2 were also subjected to transmission electron microscopy and scanning electron microscopy analysis, respectively, and Transmission Electron Microscopy (TEM) spectrograms and Scanning Electron Microscopy (SEM) spectrograms thereof are shown in FIGS. 6 and 7, respectively.
It can be seen from fig. 5 and 7 that the external morphology of both SFMSNs and MOR-SFMSNs are spherical particles, while from fig. 4 and 6, the internal morphology of both SFMSNs and MOR-SFMSNs is sunflower-like; as can be seen from comparing fig. 5 and fig. 7 with fig. 4 and fig. 6, adding MOR into SFMSNs synthesizes mesoporous composite molecular sieve without changing the morphology of the material.
The specific surface area, pore size and pore volume data of the MOR-SFMSNs provided in examples 1-10 and the MOR microporous molecular sieves provided in comparative examples, and the SFMSNs provided in comparative example 2 were also measured in this test example and are shown in table 1 below.
TABLE 1
| Examples | Specific surface area (m) 2 ·g -1 ) | Aperture (nm) | Pore volume (cm) 3 ·g -1 ) |
| Example 1 | 437 | 6.44 | 0.41 |
| Example 2 | 401 | 6.82 | 0.38 |
| Example 3 | 419 | 6.75 | 0.40 |
| Example 4 | 444 | 6.27 | 0.51 |
| Example 5 | 616 | 6.13 | 0.45 |
| Example 6 | 654 | 6.34 | 0.51 |
| Example 7 | 721 | 6.15 | 0.47 |
| Example 8 | 753 | 7.27 | 0.48 |
| Example 9 | 679 | 6.53 | 0.43 |
| Example 10 | 513 | 6.19 | 0.45 |
| Comparative example 1 | 319 | - | 0.04 |
| Comparative example 2 | 810 | 6.7 | 0.85 |
As shown in the experimental results, the SFMSNs and MOR-SFMSNs prepared by the invention are sunflower-shaped porous nano particles with specific surface area of 400-850m 2 ·g -1 Pore diameter of 5-8nm and pore volume of 0.35-0.85cm 3 ·g -1 。
Performance test case
The test example evaluates the catalytic n-heptane hydroisomerization reaction of Cat-1-Cat-12, wherein the evaluation is carried out on a fixed bed hydrogenation micro-reactor, and the conditions of the conversion rate, the selectivity and the like of the hydroisomerization of the catalyst are examined, wherein the catalyst loading amount is 2.5g, and the specific steps of the evaluation are as follows:
a: the catalyst is reduced: at a pressure of 1.5MPa, a temperature of 400 ℃ and H 2 Reducing for 4 hours under the condition of 40mL/min flow;
b: after reduction, the catalyst is cooled to the reaction temperature, and then the catalyst is cooled to H 2 Per oil=400 (v/v), pressure 1.5MPa, whsv=1.0 h -1 And the experiment data obtained by researching Cat-1-Cat-12 catalyzing the hydroisomerization reaction of n-heptane under the condition that the reaction temperature is 260 ℃ are shown in the following table 2.
TABLE 2
| Catalyst numbering | Silicon to aluminum ratio | N-heptane conversion (%) | Selectivity (%) |
| Cat-1 | 100 | 69.5 | 88.1 |
| Cat-2 | 80 | 60.1 | 76.4 |
| Cat-3 | 50 | 61.5 | 78.6 |
| Cat-4 | 120 | 65.2 | 72.9 |
| Cat-5 | 150 | 66.2 | 75.5 |
| Cat-6 | 100 | 63.5 | 72.4 |
| Cat-7 | 100 | 60.4 | 70.3 |
| Cat-8 | 100 | 66.1 | 73.7 |
| Cat-9 | 100 | 60.8 | 70.1 |
| Cat-10 | 100 | 61.1 | 69.5 |
| Cat-11 | 100 | 42.8 | 40.7 |
| Cat-12 | - | 28.5 | 21.3 |
As can be seen from Table 2, the conversion rate and selectivity of the normal alkane hydroisomerization catalyst prepared by using the mesoporous composite molecular sieve material provided by the embodiment of the invention to n-heptane are higher than those of the catalyst prepared by using a single microporous molecular sieve or a single mesoporous molecular sieve as a carrier, and when n (SiO 2 )/n(Al 2 O 3 ) At=100, the catalyst has the highest conversion rate to n-heptane and selectivity, which are the results of the combined action of the pore structure and acidity of the catalyst, and the acid properties of the catalyst, the pore structure of the carrier, the dispersity of Pt particles, and the like are closely related to the reactivity of the catalyst.
The foregoing description of the embodiments of the invention is not intended to limit the scope of the invention, so that the substitution of equivalent elements or equivalent variations and modifications within the scope of the invention shall fall within the scope of the patent. In addition, the technical features and the technical features, the technical features and the technical invention can be freely combined for use.
Claims (11)
1. A mesoporous composite molecular sieve is characterized in that the mesoporous composite molecular sieve is prepared by compositing microporous mordenite molecular sieve with organic-inorganic hybrid mesoporous silica, and has mesoporous and microporous double-pore distribution and double hysteresis rings, and the specific surface area is 400-850m 2 ·g -1 Pore volume of 0.35-0.85cm 3 ·g -1 The aperture is 5-8nm.
2. The mesoporous composite molecular sieve according to claim 1, wherein the mesoporous composite molecular sieve is sunflower-shaped.
3. The mesoporous composite molecular sieve according to claim 1 or 2, wherein, in the mesoporous composite molecular sieve, siO 2 And Al 2 O 3 The molar ratio of (2) is 50 to 400, preferably 50 to 200, more preferably 50 to 150.
4. A method for preparing a mesoporous composite molecular sieve according to any one of claims 1 to 3, comprising:
uniformly mixing a template agent, water, alcohol, an alkali source, an alkane organic solvent, an organic silicon source and an inorganic silicon source to obtain mesoporous material precursor emulsion, and adding H-type microporous mordenite molecular sieve seed crystals into the mesoporous material precursor emulsion to obtain a mesoporous composite molecular sieve;
wherein, inorganic silicon source: organosilicon source: seed crystal of H-type microporous mordenite molecular sieve: template agent: water: alkali source: alcohol: the molar ratio of alkane organic solvent is 1 (0.03-0.2) (0.005-0.025) (0.1-0.25) (500-750) (0.75-1.0) (40-60) (10-50);
Wherein, the dosage of the inorganic silicon source and the organic silicon source is SiO 2 The dosage of the H-type microporous mordenite molecular sieve seed crystal is calculated by Al 2 O 3 And (5) counting.
5. The preparation method according to claim 4, characterized in that it comprises the following specific steps:
(1) Adding the H-type microporous mordenite molecular sieve seed crystal, an alkali source and alcohol into water, and uniformly mixing;
(2) Adding a template agent into the solution obtained in the step (1) and uniformly mixing;
(3) Adding an organosilicon source into the solution obtained in the step (2) and uniformly mixing;
(4) Adding a template agent into the solution obtained in the step (3) and uniformly mixing; preferably, the molar ratio of the template agent in step (4) to the template agent in step (2) is 2-4:1;
(5) Adding an alkane organic solvent and an inorganic silicon source into the solution obtained in the step (4) and uniformly mixing;
(6) And (3) filtering the solution obtained in the step (5), drying the obtained solid product, extracting the template agent in the solid product, and drying to obtain the mesoporous composite molecular sieve.
6. The method of preparing according to claim 4 or 5, wherein the method of preparing H-type microporous mordenite molecular sieve seeds comprises:
1) Mixing silicon source, aluminum source, alkali source and water uniformly, wherein the molar ratio of the raw materials is (5.0-10.0) Na 2 O:Al 2 O 3 :(10-100)SiO 2 :(500-1500)H 2 O；
2) Crystallizing the solution obtained in the step 1) to obtain microporous mordenite molecular sieve microcrystalline emulsion, and filtering, washing, drying and roasting to obtain microporous mordenite molecular sieve raw powder;
3) And carrying out ion exchange on the microporous mordenite molecular sieve raw powder and an ammonium salt solution for a plurality of times, and then filtering, drying and roasting to finally obtain the H-type microporous mordenite molecular sieve seed crystal.
7. The method of claim 4 or 5, wherein the organosilicon source comprises one or a combination of 1, 2-bis (triethoxysilyl) ethane (BTEE), 1, 2-bis (trimethoxysilyl) ethane (BTME), 1, 4-bis (triethoxysilyl) benzene (BTEB);
preferably, the inorganic silicon source comprises one or a combination of a plurality of silica sol, tetraethyl orthosilicate and water glass;
still preferably, the alkali source comprises ammonia and/or sodium hydroxide;
still preferably, the template agent comprises one or a combination of a plurality of octadecyl trimethyl ammonium chloride, hexadecyl trimethyl ammonium chloride and hexadecyl trimethyl ammonium bromide;
still preferably, the alkane organic solvent includes one or a combination of several of n-hexane, cyclohexane and n-pentane;
Also preferably, in the preparation process of the mesoporous and microporous composite molecular sieve, the temperature is controlled to be 25-40 ℃.
8. The method according to claim 6, wherein in step 1), the silicon source comprises one or a combination of several of silica sol, water glass and tetraethyl orthosilicate;
the aluminum source comprises one or a combination of several of sodium metaaluminate, aluminum oxide, aluminum chloride and aluminum nitrate;
the alkali source comprises Na 2 CO 3 And/or NaOH;
preferably, in the step 2), the crystallization temperature is 100-200 ℃ and the time is 24-48h;
the temperature of the drying is 50-100 ℃ and the time is 6-12h;
the roasting temperature is 400-600 ℃, and the roasting time is 4-8h;
still preferably, in step 3), the ammonium salt comprises one or a combination of more of ammonium chloride, ammonium nitrate and ammonium sulfate, and the mass ratio of the ammonium salt to the microporous mordenite molecular sieve raw powder is 1-5:1;
the temperature of the ion exchange is 50-100 ℃ and the time is 1-5h;
the temperature of the drying is 50-100 ℃ and the time is 6-12h;
the roasting temperature is 400-600 ℃ and the roasting time is 3-8h.
9. A normal alkane hydroisomerization catalyst comprising a carrier and an active component supported on the carrier, wherein the carrier is the mesoporous composite molecular sieve according to any one of claims 1 to 3, the active component is noble metal, and the loading amount of the noble metal is 0.5 to 1wt% based on 100% of the total weight of the carrier;
Preferably, the noble metal comprises at least one of a group VIII metal, more preferably Pt.
10. The method for preparing the normal alkane hydroisomerization catalyst according to claim 9, characterized in that the preparation method comprises:
dipping the aqueous solution of the noble metal precursor on a mesoporous composite molecular sieve carrier, and then carrying out ultrasonic treatment, drying and roasting to obtain the normal alkane hydroisomerization catalyst;
preferably, the time of the ultrasonic treatment is 30-60min;
also preferably, the drying temperature is 50-100 ℃ and the drying time is 6-12h;
also preferably, the roasting temperature is 300-500 ℃ and the time is 2-6h;
also preferably, when the noble metal is Pt, the noble metal precursor is chloroplatinic acid hexahydrate and/or nitrotetraamineplatinum.
11. Use of the normal paraffin hydroisomerization catalyst of claim 9 in a normal paraffin hydroisomerization reaction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211580740.8A CN115991484A (en) | 2022-12-09 | 2022-12-09 | Mesoporous composite molecular sieve and preparation thereof, normal alkane hydroisomerization catalyst and preparation and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211580740.8A CN115991484A (en) | 2022-12-09 | 2022-12-09 | Mesoporous composite molecular sieve and preparation thereof, normal alkane hydroisomerization catalyst and preparation and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115991484A true CN115991484A (en) | 2023-04-21 |
Family
ID=85989754
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211580740.8A Pending CN115991484A (en) | 2022-12-09 | 2022-12-09 | Mesoporous composite molecular sieve and preparation thereof, normal alkane hydroisomerization catalyst and preparation and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115991484A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117339636A (en) * | 2023-09-27 | 2024-01-05 | 黑龙江大学 | Method for preparing hierarchical porous zeolite supported bimetallic alloy bifunctional catalyst by adopting room-temperature electron reduction method and application thereof |
-
2022
- 2022-12-09 CN CN202211580740.8A patent/CN115991484A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117339636A (en) * | 2023-09-27 | 2024-01-05 | 黑龙江大学 | Method for preparing hierarchical porous zeolite supported bimetallic alloy bifunctional catalyst by adopting room-temperature electron reduction method and application thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104646050B (en) | A kind of hydrogenation catalyst and its preparation and application | |
| CN109731608A (en) | A kind of bifunctional catalyst and preparation method thereof without sodium Si-Al molecular sieve of package metals nano particle | |
| CN101596462B (en) | Hydroisomerizaion catalyst and preparation method thereof | |
| CN106582805B (en) | A method of SAPO-11/MOR composite molecular screen is prepared with preset MOR crystal seed | |
| CN109772443A (en) | A kind of molecular sieve carried high dispersive Pt catalyst of ZSM-12 and preparation method thereof | |
| JP2002521303A (en) | Method for producing molecular sieve | |
| CN110773225B (en) | Core-shell structure hydroisomerization catalyst, and preparation method and application thereof | |
| CN107303497B (en) | A kind of multi-stage porous dehydrogenation and preparation method thereof | |
| CN106430238B (en) | Method and the application of multilevel pore channel SAPO-11 molecular sieve are prepared using plant cellulose as template | |
| CN111569935A (en) | Catalyst for preparing p-xylene, preparation method and application thereof | |
| CN105597815B (en) | ZSM-5/ZnVPI-8 composite molecular sieves catalyst | |
| CN115991484A (en) | Mesoporous composite molecular sieve and preparation thereof, normal alkane hydroisomerization catalyst and preparation and application thereof | |
| CN112794338A (en) | ZSM-5 molecular sieve and preparation method and application thereof | |
| CN115108563B (en) | ZSM-48 molecular sieve and preparation method thereof, low-carbon alkane isomerization catalyst and preparation method and application thereof | |
| CN113058637B (en) | Alkane double-branched chain isomerization catalyst and preparation method thereof | |
| CN109806910A (en) | A kind of molecular sieve carried high-dispersion metal catalyst of H-type EUO and preparation method thereof | |
| CN114130426B (en) | Catalytic cracking catalyst for high-yield low-carbon olefin by hydrogenating LCO (liquid Crystal on silicon), and preparation method and application thereof | |
| CN114425396A (en) | Supported non-noble metal catalyst, preparation method and application thereof, and low-carbon alkane dehydrogenation method | |
| CN108946756B (en) | Hierarchical pore EUO structure molecular sieve and synthesis method thereof | |
| CN106629772A (en) | Method for preparing hierarchical porous SAPO-11 molecular sieve by using templating agent P123-containing SBA-15 as silicon source | |
| CN108452839B (en) | Mesoporous-microporous composite molecular sieve, catalyst, preparation method and application thereof | |
| CN106799257A (en) | A kind of alkane isomerization catalyst and preparation method thereof | |
| CN113830778B (en) | ZSM-5/beta core-shell molecular sieve and synthesis method and application thereof | |
| CN106622361B (en) | A method of SAPO-11/MOR composite molecular screen is prepared by silicon source of MOR | |
| JP2019034879A (en) | Mfi zeolite |
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 |