阅读说明：本技术 一种次级分子筛及其用途 (Secondary molecular sieve and application thereof ) 是由 杨博婷 于 2021-01-08 设计创作，主要内容包括：本发明公开了一种次级分子筛及其用途；其制备方法包括：将层状前驱体Al-PLS-3加入至莽草酸衍生物溶液中,在室温条件下搅拌25～45min,然后将其置于反应釜中,在150～180条件下反应20min～24h,得到反应产物A；将反应产物抽滤,用去离子水冲洗,在70～90℃下烘干,得到反应产物B；将反应产物B置于500～600℃马弗炉中焙烧6～12h,冷却至室温,得到次级分子筛。本发明是一种具有优良的催化活性,吸附能力以及具有较大的比表面与孔容,且具有优良水热稳定性的次级分子筛,其在石油、化学工业中具有广泛用途。(The invention discloses a secondary molecular sieve and application thereof; the preparation method comprises the following steps: adding a layered precursor Al-PLS-3 into a shikimic acid derivative solution, stirring at room temperature for 25-45 min, then placing the solution into a reaction kettle, and reacting at 150-180 ℃ for 20 min-24 h to obtain a reaction product A; carrying out suction filtration on the reaction product, washing with deionized water, and drying at 70-90 ℃ to obtain a reaction product B; and (3) roasting the reaction product B in a muffle furnace at 500-600 ℃ for 6-12 h, and cooling to room temperature to obtain the secondary molecular sieve. The invention is a secondary molecular sieve with excellent catalytic activity, adsorption capacity, larger specific surface and pore volume and excellent hydrothermal stability, and has wide application in petroleum and chemical industries.)

1. A shikimic acid derivative having the structural formula:

2. use of a shikimic acid derivative according to claim 1 in the preparation of a molecular sieve.

3. A secondary molecular sieve prepared from a layered precursor Al-PLS-3 by acid treatment of a shikimic acid derivative as claimed in claim 1.

4. A method of making a secondary molecular sieve as claimed in claim 3, comprising the steps of:

adding a layered precursor Al-PLS-3 into a shikimic acid derivative solution, stirring at room temperature for 25-45 min, then placing the solution into a reaction kettle, and reacting at 150-180 ℃ for 20 min-24 h to obtain a reaction product A;

carrying out suction filtration on the reaction product, washing with deionized water, and drying at 70-90 ℃ to obtain a reaction product B;

and roasting the reaction product B in a muffle furnace at 500-600 ℃ for 6-12 h, and cooling to room temperature to obtain the secondary molecular sieve.

5. The method of claim 4, wherein the secondary molecular sieve is prepared by: the layered precursor Al-PLS-3 is 1.5-3.5 parts by weight, and the shikimic acid derivative solution is 0.2-0.8 part by weight.

6. Use of the secondary molecular sieve of claim 3 in the petroleum and/or chemical industry.

7. Use of a shikimic acid derivative according to claim 1 for increasing the catalytic effect of a secondary molecular sieve.

8. Use of shikimic acid derivatives according to claim 7, characterized in that: the shikimic acid derivative is used for improving the catalytic TIPB cracking reaction of the secondary molecular sieve.

9. Use of shikimic acid derivatives according to claim 7, characterized in that: the shikimic acid derivative can be used for improving the application of the secondary molecular sieve in catalytic esterification reaction.

10. Use of geniposide in improving the hydrothermal stability of a secondary molecular sieve.

Technical Field

The invention belongs to the field of preparation of secondary molecular sieves, and particularly relates to a secondary molecular sieve and application thereof.

Background

Solid porous materials play an important role in modern society due to their wide application in the chemical processing industry, commodity production, optics, electronics, and medicine. In general, solid matrices composed of pores and/or voids are considered porous materials. Virtually all solid materials can provide a porous medium, and thus the chemistry of porous materials becomes very rich, covering all the important branches of materials such as inorganic crystals, organic crystals, carbon, polymers, glass, ceramics, metals, and the like.

Molecular sieves are a class of solid crystalline materials with independent molecular scale microporous pore channels, with exchangeable extra-framework cations. Molecular sieves can be viewed as host frameworks having an integral and invariable three-dimensional framework structure, according to the principle of host-guest interaction. They exhibit excellent catalytic and adsorptive properties while taking into account environmental friendliness. Molecular sieves have important commercial applications as catalysts in hydrocarbon conversion processes in the petroleum and chemical industries, as adsorbents in small molecule separation processes, or as ion exchangers in detergents, and the like. The excellent performance of molecular sieves is closely related to their structural properties.

Prior artPublished application No. CN 1843626 a discloses a medium-micropore composite silicon molecular sieve and its preparation and use; the mesoporous and microporous composite Qinsi molecular sieve belongs to a pure-phase molecular sieve, has a disordered vermicular pore canal structure and hasOf mesopores andthe micropores of (1) contain in their pore walls the primary and secondary structural units of the microporous molecular sieve. The preparation of the molecular sieve adopts a two-step method, firstly a precursor containing primary and secondary structural units of the titanium silicalite TS-1 is prepared, and then the precursor and long-chain alkylamine are self-assembled to obtain the mesoporous and microporous composite titanium silicalite molecular sieve. Application publication No. CN 1488577A discloses a mesoporous molecular sieve containing a secondary structure unit of Y zeolite and a preparation method thereof; the synthesis mixture is pretreated, then the obtained inorganic precursor is subjected to supermolecule self-assembly by using a mixed cation-anion surfactant as a template agent, and a secondary structure unit of the Y zeolite is introduced into a framework of a mesoporous molecular sieve, so that the SBU-MCM-41 composite molecular sieve with different silica-alumina ratios is successfully designed and synthesized.

Disclosure of Invention

The invention aims to provide a shikimic acid derivative.

The technical scheme adopted by the invention for realizing the purpose is as follows:

a shikimic acid derivative having the structural formula:

preferably, a shikimic acid derivative prepared from 5-methyl-heptanone modified shikimic acid.

Preferably, the yield of the shikimic acid derivative is 70.3-72.5%.

Preferably, the shikimic acid derivative is prepared as follows:

dissolving shikimic acid and 5-methyl-heptanone in dichloromethane according to the molar ratio of 1: 3-6 in parts by weight, adding 0.01-0.015% of p-toluenesulfonic acid, carrying out catalytic reaction for 3-5 hours at 45-50 ℃, and recrystallizing to obtain a product A; and hydrolyzing the product A at 50-60 ℃ under an acidic condition, recrystallizing, and filtering to obtain the shikimic acid derivative, wherein the yield is 70.3-72.5%.

The invention also discloses the use of the shikimic acid derivative in the preparation of molecular sieves.

Another object of the present invention is to provide a secondary molecular sieve having excellent catalytic activity, adsorption capacity, large specific surface area and pore volume, and excellent hydrothermal stability, which has wide applications in the petroleum and chemical industries.

The invention discloses a secondary molecular sieve which is prepared by treating a layered precursor Al-PLS-3 with shikimic acid derivative acid.

The technical scheme adopted by the invention for realizing the purpose is as follows:

a method for preparing a secondary molecular sieve, comprising the steps of:

adding a layered precursor Al-PLS-3 into a shikimic acid derivative solution, stirring at room temperature for 25-45 min, then placing the solution into a reaction kettle, and reacting at 150-180 ℃ for 20 min-24 h to obtain a reaction product A;

carrying out suction filtration on the reaction product, washing with deionized water, and drying at 70-90 ℃ to obtain a reaction product B;

and (3) roasting the reaction product B in a muffle furnace at 500-600 ℃ for 6-12 h, and cooling to room temperature to obtain the secondary molecular sieve.

The method comprises the steps of placing a layered precursor Al-PLS-3 into a shikimic acid derivative solution for acid treatment, and modifying the layered precursor Al-PLS-3 to obtain a secondary molecular sieve; in the acid treatment process, the acid treatment time is shortened, so that the template agent between parent layers is gradually removed, the removal rate is higher, the rearrangement of hydrogen bond groups between the layers is caused, and finally, the material with the outer specific surface of the laminate which is randomly arranged along the layered direction and is more exposed is formed; the obtained secondary molecular sieve has larger external specific surface area and micropore volume, becauseTherefore, the secondary molecular sieve has better adsorption capacity and catalytic activity; after the layered precursor Al-PLS-3 is subjected to acid treatment of shikimic acid derivatives, the appearance of the layered precursor Al-PLS-3 is not influenced; in addition, the obtained secondary molecular sieve has deeper catalytic cracking reaction on esterification reaction and cracking reaction of TIPB, p-Diisopropylbenzene (DIPB), Isopropylbenzene (IPB) and Benzene (BZ), and meanwhile, the Friedel-crafts acylation reaction on anisole and acetic anhydride and the catalysis of CO₂Reforming to produce CH₄Has better catalytic action and the secondary molecular sieve has better hydrothermal stability.

Preferably, the layered precursor Al-PLS-3 accounts for 1.5-3.5 parts by weight, and the shikimic acid derivative solution accounts for 0.2-0.8 part by weight.

More preferably, the layered precursor Al-PLS-3 is prepared as follows:

mixing Al (NO)₃)₃·9H₂Dissolving O and NaOH in a TEAOH aqueous solution with the concentration of 20-30 wt%, stirring until the solution is clear, adding a silicon source H-kanemite, and stirring for 25-30 min at room temperature. H-kanemite, Al (NO) in each component₃)₃·9H₂O, NaOH, deionized water and TEAOH according to the molar ratio: SiO 2₂:Al₂O₃:TEA+:yNaOH:H₂0.8-1.2: 1/x: 0.1-0.3: 0.03-0.05: 6.0-6.8, wherein x is 30- ∞, and y is 0-0.4; putting the uniformly stirred synthetic raw materials into a reaction kettle, statically crystallizing for 4-24 hours at the temperature of 150-175 ℃, centrifuging, and drying to obtain a product; and roasting the product for 8-12 h in an air atmosphere at 500-600 ℃ to obtain a layered precursor Al-PLS-3.

Preferably, the concentration of the shikimic acid derivative solution is 0.05-0.15 mol/L.

The invention also discloses the use of the secondary molecular sieve in the petroleum and/or chemical industry.

The invention also discloses the use of the shikimic acid derivative in improving the catalytic action of the secondary molecular sieve.

Preferably, the use of a shikimic acid derivative for increasing the catalytic TIPB cleavage reaction of a secondary molecular sieve.

Preferably, the use of shikimic acid derivatives for increasing the secondary molecular sieve in catalyzing esterification reactions.

The invention also discloses application of the geniposide in improving the hydrothermal stability of the secondary molecular sieve.

In order to further improve the specific surface area, adsorption capacity and catalytic action of the secondary molecular sieve and enable the secondary molecular sieve to have better hydrothermal stability, the preferable measures further comprise:

adding a layered precursor Al-PLS-3 into a mixed solution of shikimic acid derivatives and geniposidic acid with the concentration of 0.05-0.15 mol/L for acid treatment, wherein the weight ratio of the shikimic acid derivatives to the geniposidic acid is 1: 0.2-0.8, and obtaining a secondary molecular sieve; the addition of the geniposide further improves the specific surface area, the adsorption capacity and the catalytic action of the secondary molecular sieve, and simultaneously ensures that the secondary molecular sieve has better hydrothermal stability; the reason may be that shikimic acid derivatives act synergistically with geniposide providing sufficient OH^-The molecular sieve enters a layered structure and has a larger steric hindrance structure, so that the interlayer spacing is further increased, and the molecular sieve with larger aperture is obtained, so that the specific surface area of the secondary molecular sieve is increased; meanwhile, the adsorption capacity and the catalytic action of the secondary molecular sieve are improved, and the secondary molecular sieve has better hydrothermal stability.

Because the invention adopts the invention to place the layered precursor Al-PLS-3 in the shikimic acid derivative solution for acid treatment and modify the layered precursor Al-PLS-3 to obtain the secondary molecular sieve, the invention has the following beneficial effects: in the acid treatment process, the acid treatment time is short, so that the template agent between parent layers is gradually removed, the removal rate is high, the rearrangement of hydrogen bond groups between the layers is caused, and finally a material which is arranged in a disordered way and has a more exposed outer specific surface is formed; the obtained secondary molecular sieve has larger external specific surface area and micropore volume; and the shape of the layered precursor Al-PLS-3 is not influenced after the acid treatment of the shikimic acid derivative; in addition, the obtained secondary molecular sieve has deeper catalytic cracking reaction on esterification reaction and TIPB cracking reaction, and p-Diisopropylbenzene (DIPB), Isopropylbenzene (IPB) and Benzene (BZ), and meanwhile, Friedel-crafts acylation reaction on anisole and acetic anhydrideReaction and catalysis of CO₂Reforming to produce CH₄Has better catalysis effect; in addition, the secondary molecular sieve has excellent hydrothermal stability. Therefore, the invention is a secondary molecular sieve which has excellent catalytic activity, adsorption capacity, larger specific surface and pore volume and excellent hydrothermal stability, and has wide application in petroleum and chemical industries.

Drawings

FIG. 1 is an XRD spectrum of a layered precursor Al-PLS-3-60 and a secondary molecular sieve in example 1;

FIG. 2 is a TG curve of a layered precursor Al-PLS-3-60 and a secondary molecular sieve in example 1;

FIG. 3 is an SEM image of Al-PLS-3-60 after firing;

FIG. 4 is an SEM image of the calcined secondary molecular sieve of example 1;

FIG. 5 shows the N of the secondary molecular sieve and the layered precursor Al-PLS-3-60 of example 1₂Adsorption-desorption curves;

FIG. 6 is the Ar adsorption isotherm of the secondary molecular sieve with the layered precursor Al-PLS-3-60 of example 1;

FIG. 7 is a graph showing the vacuum infrared and 2,6-DTBPy adsorption spectra of the secondary molecular sieve and Al-PLS-3-60 of example 1 after calcination;

FIG. 8 shows catalytic cracking reaction catalytic rates of secondary molecular sieves for TIPB;

FIG. 9 shows the catalytic efficiency of the secondary molecular sieve p-Diisopropylbenzene (DIPB) cracking reaction;

FIG. 10 shows the catalytic efficiency of a secondary molecular sieve for cumene (IPB) cleavage reaction;

FIG. 11 is a graph of the catalytic efficiency of a secondary molecular sieve for a Benzene (BZ) cracking reaction;

FIG. 12 is the results of a secondary molecular sieve catalyzed Friedel-crafts acylation of anisole and acetic anhydride;

FIG. 13 shows secondary molecular sieve vs. CO₂Reforming to produce CH₄Post catalytic CH₄The conversion of (a);

fig. 14 is the external specific surface area of the secondary molecular sieve versus the total pore volume retention.

Detailed Description

The experimental methods described in the following examples of the present invention are all conventional methods unless otherwise specified; the reagents and materials are commercially available, unless otherwise specified.

Further, in some specific examples, the shikimic acid derivatives are prepared as follows:

dissolving shikimic acid and 5-methyl-heptanone in dichloromethane according to the molar ratio of 1:5 in parts by weight, adding 0.012% of p-toluenesulfonic acid, carrying out catalytic reaction for 4 hours at 48 ℃, and recrystallizing to obtain a product A; then hydrolyzing the product A under the acid condition of 55 ℃, recrystallizing and filtering to obtain shikimic acid derivatives, wherein the yield is 71.5 percent, and the structural formula is as follows:

further, in some specific embodiments, the layered precursor Al-PLS-3 is prepared as follows:

mixing Al (NO)₃)₃·9H₂Dissolving O and NaOH in a TEAOH aqueous solution with the concentration of 28 wt%, stirring until the solution is clear, adding a silicon source H-kanemite, and stirring for 30min at room temperature. H-kanemite, Al (NO) in each component₃)₃·9H₂O, NaOH, deionized water and TEAOH according to the molar ratio: SiO 2₂:Al₂O₃:TEA+:yNaOH:H₂O1: 1/50:0.3:0.05: 6.4; putting the uniformly stirred synthetic raw materials into a reaction kettle, statically crystallizing at 165 ℃ for 12 hours, centrifuging, and drying to obtain a product; and roasting the product for 8 hours at 550 ℃ in an air atmosphere to obtain a layered precursor Al-PLS-3.

The technical solution of the present invention is further described in detail below with reference to the following detailed description and the accompanying drawings:

example 1

A method for preparing a secondary molecular sieve, comprising the steps of:

adding 2.1 parts by weight of layered precursor Al-PLS-3 into 0.6 part by weight of shikimic acid derivative solution with the concentration of 0.12mol/L, stirring for 30min at room temperature, then putting the mixture into a reaction kettle with a polytetrafluoroethylene lining, and reacting for 8h at 160 ℃ to obtain a reaction product A;

carrying out suction filtration on the reaction product A, washing with deionized water, and drying at 80 ℃ to obtain a reaction product B;

and (3) roasting the reaction product B in a muffle furnace at 550 ℃ for 7h, and cooling to room temperature to obtain the secondary molecular sieve.

Example 2

A method for preparing a secondary molecular sieve, comprising the steps of:

adding 3.3 parts by weight of layered precursor Al-PLS-3 into 0.4 part by weight of shikimic acid derivative solution with the concentration of 0.08mol/L, stirring for 35min at room temperature, then putting the mixture into a reaction kettle with a polytetrafluoroethylene lining, and reacting for 12h at 180 ℃ to obtain a reaction product A;

the other steps were the same as in example 1.

Example 3

A method for preparing a secondary molecular sieve, the other steps are the same as example 1, except that: carrying out suction filtration on the obtained reaction product A, washing with deionized water, and drying at 90 ℃ to obtain a reaction product B; and (3) roasting the reaction product B in a muffle furnace at 600 ℃ for 10h, and cooling to room temperature to obtain the secondary molecular sieve.

Example 4

A method for preparing a secondary molecular sieve, the other steps are the same as example 1, except that: adding 2.1 parts by weight of layered precursor Al-PLS-3 into 0.6 part by weight of mixed solution of shikimic acid derivative and geniposidic acid with the concentration of 0.12, wherein the weight ratio of the shikimic acid derivative to the geniposidic acid is 1:0.5, stirring for 30min at room temperature, then putting the mixture into a reaction kettle with a polytetrafluoroethylene lining, and reacting for 8h at 160 ℃ to obtain a reaction product A;

comparative example 1

A method for preparing a secondary molecular sieve, the other steps are the same as example 1, except that: and (3) replacing the shikimic acid derivative solution with a hydrochloric acid ethanol solution to perform acid treatment on the layered precursor Al-PLS-3.

Comparative example 2

A method for preparing a secondary molecular sieve, the other steps are the same as example 1, except that: and replacing the shikimic acid derivative solution with an acetic acid solution to perform acid treatment on the layered precursor Al-PLS-3.

Test example 1:

1. measurement of nuclear magnetism of shikimic acid derivative

The synthesized material was measured by a JNM-GX400 type instrument (internal standard TMS) nuclear magnetic resonance apparatus (NMR) (Hitachi Co.).

¹H NMR(CDCl₃)：0.99(d,3H,CH₃)，1.67(m,1H,CH)，1.53(m,2H,CH₂)，1.57(d,2H,CH₂)，0.93(t,6H,CH₃)，1.61(m,2H,CH₂)，3.59(d,1H,OH)，3.72(m,1H,CH)，4.05(t,1H,CH)，6.98(d,1H,CH)，2.18(d,2H,CH₂) 11.3(s,1H, COOH), from nuclear magnetic characterization data, yielded shikimic acid derivatives prepared from 5-methyl-heptanone modified shikimic acid.

Test example 2:

1. determination of secondary molecular sieve XRD spectrogram

The structure of the material was characterized by X-ray diffraction pattern (XRD) using a Rigaku Ultima IV model and a Cu-Ka as the radiation sourceAnd (3) testing conditions are as follows: current 25mA, voltage 35kV, step size 0.02 degree, scanning range 5-35 degree, scanning speed 10 degree min^-1。

FIG. 1 is an XRD spectrum of a layered precursor Al-PLS-3-60 and a secondary molecular sieve in example 1. As can be seen from FIG. 1, FIGS. a and d are XRD spectra before and after calcination of Al-PLS-3-60, and FIGS. b and c are XRD spectra before and after calcination of the secondary molecular sieve of example 1. Al-PLS-3-60 shows a (200) characteristic diffraction peak corresponding to the layered structure; after firing, the (200) diffraction peak shifts to high angles, forming a 3D FER structure. The XRD spectrogram of the secondary molecular sieve obtained after the Al-PLS-3-60 is subjected to acid treatment is greatly different from that of the Al-PLS-3-60; compared with Al-PLS-3-60, the diffraction peaks of (200), (220), (400), (040) and the like of the prepared secondary molecular sieve are broadened and weakened, and the diffraction peaks of (020), (011) and (002) have better retention; this phenomenon indicates that, at the initial stage of shikimic acid derivative treatment, the hydrogen bond groups between the sample layers may be recombined, resulting in structural disorder of the secondary molecular sieve in the layer direction; may be caused primarily by the partial removal of the interlevel organic templating agent; after roasting, (200) the characteristic peak is further widened, and (202) the diffraction peak shifts to a high angle, and other diffraction peaks are further weakened and widened to form a material with a more disordered structure.

2. Determination of secondary molecular sieve thermogravimetry

The content of organic matters in the experimental material is tested by thermogravimetry, and the instrument model is Mettler TGA/SDTA 851 e. And (3) testing conditions are as follows: 298-1073K, and the heating rate is 10 K.min^-1Gas flow rate 40mL/min^-1。

FIG. 2 is a TG curve of the layered precursor Al-PLS-3-60 and the secondary molecular sieve of example 1. As can be seen from FIG. 2, a is the thermogravimetric curve of Al-PLS-3-60, Al-PLS-3-60 has 24.6% of template molecules (template is TEAOH), and after treatment for 30min with shikimic acid derivatives, the weight loss percentage of the prepared secondary molecular sieve is about 5%, i.e. the secondary molecular sieve contains 5% of template molecules; this shows that Al-PLS-3-60 was treated with shikimic acid derivative for 30min, i.e., in a short acidification time, 19.6% of the template was removed, while the secondary molecular sieve in comparative example 1 was 8.5% of the template removed, and the secondary molecular sieve in comparative example 2 contained 11.4% of the template after acid treatment, and the removal rate of the template in the secondary molecular sieve in example 1 was higher than that in comparative examples 1-2, compared to comparative examples 1-2, and thus Al-PLS-3-60 had a higher removal rate of the template after acid treatment with shikimic acid derivative for 30 min.

3. Determination of surface morphology of secondary molecular sieve

The crystalline morphology of the experimental material is characterized by a Scanning Electron Microscope (SEM) with an instrument model of Hitachi S-4800.

FIGS. 3 and 4 are SEM pictures of Al-PLS-3-60 and the secondary molecular sieve of example 1 after calcination, respectively. As can be seen from FIGS. 3 and 4, there is a difference from the XRD data in terms of long-range order, and the two are almost the same in crystalline morphology, and are rod-shaped grains with a grain size of 60-140nm, which indicates that Al-PLS-3-60 does not damage the morphology of the sample after acid treatment.

4. Secondary molecular sieve N₂Determination of adsorption-desorption Curve

The specific surface area and the pore volume property of the experimental material are measured by a nitrogen adsorption and desorption isotherm, and the model of the nitrogen adsorption and desorption isotherm instrument is BELSORP-MAX. And (3) testing conditions are as follows: the temperature is-195 ℃, the mass of a sample to be detected is about 110mg, the activation condition is that the temperature is raised to 300 ℃ for activation for 6h after the activation is carried out for 2h at 120 ℃. The specific surface area and pore volume of the samples were calculated by the Brunauer-Emmertt-Teller (BET) method.

FIG. 5 shows the N of the secondary molecular sieve and the layered precursor Al-PLS-3-60 of example 1₂Adsorption-desorption curve. As can be seen from FIG. 5, curve a is N of the layered precursor Al-PLS-3-60₂Adsorption-desorption curve, curve b is N of the secondary molecular sieve in example 1₂Adsorption-desorption curves; at P/P₀<When the molecular sieve is 0.7, the layered precursor Al-PLS-3-60 shows better adsorption performance, and the adsorption performance of the secondary molecular sieve is lower than that of the Al-PLS-3-60; P/P₀And when the adsorption capacity is 0.7-1.0, the adsorption performance of the secondary molecular sieve is higher than that of a layered precursor Al-PLS-3-60, and finally the same adsorption capacity is shown.

5. Determination of secondary molecular sieve Ar adsorption isotherm

In this experiment, the pore size distribution of the material was characterized by Ar adsorption using an instrument model Micromeritics ASAP 2020. And (3) testing conditions are as follows: the temperature is-185 ℃, and the mass of the sample to be detected is about 110 mg; the activation conditions are as follows: activating at 120 deg.C for 2 hr, heating to 300 deg.C, and activating for 6 hr. The pore size distribution of the sample was calculated by the method of Horvath-Kawazoe (HK).

FIG. 6 is the Ar adsorption isotherm of the calcined secondary molecular sieve and the layered precursor Al-PLS-3-60 of example 1. As can be seen from FIG. 6, a is the Ar adsorption isotherm of Al-PLS-3-60 after calcination, and b is the Ar adsorption curve of the prepared secondary molecular sieve after calcination(ii) a Ar adsorption isotherm of Al-PLS-3-60 roasted at specific pressure P/P₀About 5.5X 10^-4There is a sharp inflection point corresponding to the filling of the ten-membered ring channels; the adsorption isotherm of the calcined secondary molecular sieve is relatively insignificant, which indicates that part of the ten-membered ring channels may be destroyed due to the disordered stacking of FER plates. When P/P is present₀>At 0.15, there was a significant increase, eventually reaching a level similar to Al-PLS-3-60, indicating that the secondary molecular sieve prepared had a larger external specific surface area in its structure.

6. Determination of vacuum infrared and 2,6-DTBPy adsorption pattern of secondary molecular sieve

The infrared spectrum of the experimental material is measured by a Nicolet Nexus 670 Fourier transform infrared spectrometer. And (3) testing conditions are as follows: wavelength range 400-4000cm^-1Resolution of 4cm^-1And scan number 64. The sample is subjected to tabletting molding before testing, and the size of the molded sample is 4.8 mg-cm^-2. Placing the sample piece into a container with CaF₂And (3) carrying out vacuum treatment in a quartz pool of the window, vacuumizing for 2h under the condition of 723K, and collecting a vacuum infrared spectrum of the sample after cooling to room temperature. And after data acquisition is finished, introducing pyridine into the sample pool at 298K, adsorbing the pyridine by the sample for 0.5h, and then performing pyridine desorption (423-. In the experiment, 2, 6-di-tert-butylpyridine (2,6-DTBPy) is used as a probe molecule to analyze the acidity of the material. Because the 2,6-DTBPy is a macromolecular probe, the 2,6-DTBPy can only be selectively adsorbed on the outer surface of the material and can not enter a micropore channel, the 2,6-DTBPy can be used as an effective method for detecting the acidity of the outer surface of the catalyst.

FIG. 7 is a graph showing the vacuum infrared and 2,6-DTBPy adsorption patterns of the secondary molecular sieve and Al-PLS-3-60 of example 1 after calcination. As shown in FIG. 7, curve a is the vacuum infrared spectrum of Al-PLS-3-60, curve b is the 2,6-DTBPy adsorption spectrum of Al-PLS-3-60, curve c is the vacuum infrared spectrum of the secondary molecular sieve, and curve d is the 2,6-DTBPy adsorption spectrum of the secondary molecular sieve. The roasted Al-PLS-3-60 is 3685cm^-1Near and 3745cm^-1Characteristic absorption peaks corresponding to framework aluminum and terminal silicon hydroxyl groups are shown nearby. In thatAfter 2,6-DTBPy adsorption, it was 3685cm^-1The peak intensity of the near characteristic peak is not obviously changed and is 3375cm^-1，1648cm^-1And 1532cm^-1Is shown corresponding to DTBPyH⁺Characteristic peaks of the vibration of the medium N-H bond and the vibration of the corresponding pyridine ring. Wherein, 3375cm^-1The absorption peaks shown nearby can prove that strong B acid centers exist on the surface of Al-PLS-3-60. For the secondary molecular sieve in example 1, it was 3745cm, compared with Al-PLS-3-60^-1Near 3685cm^-1The absorption peak near this is almost completely retained, indicating that 35min of acid treatment is less damaging to the framework aluminum. 3375cm after adsorption of 2,6-DTBPy^-1A strong absorption peak appears nearby, and 3685cm^-1The intensity of the nearby characteristic peak is obviously weakened. This indicates that the secondary molecular sieve is prepared with more active sites exposed on the outer surface for easy access by macromolecular substrates.

7. Determination of specific surface area and micropore volume of secondary molecular sieve

The method for measuring the specific surface area and the micropore volume of the secondary molecular sieve in the experiment is the same as that of test example 2: 2. secondary molecular sieve N₂Measurement of adsorption-desorption curves ", the test results are shown in table 1.

TABLE 1 physicochemical and structural Properties of the samples

As can be seen from Table 1, the total specific surface area of examples 1 to 3 was less than 425m²·g^-1And the pore volume of the porous material is less than 0.1cm³·g^-1Comparing examples 1-3 with Al-PLS-3, the total specific surface area and micropore volume of examples 1-3 are lower than those of Al-PLS-3, which shows that the total specific surface area and micropore volume of the molecular sieve after the Al-PLS-3 is treated with shikimic acid derivative acid for 30min are lower than those of the original sample; the reason may be thatCaused by the disorder of the laminated plate stack after the Al-PLS-3 is treated by shikimic acid derivative acid; comparing example 1 with example 4, the total specific surface area and the micropore volume of example 4 are higher than those of example 1, which shows that the acid treatment of the layered precursor Al-PLS-3 in the mixed solution of shikimic acid derivative and geniposide acid further improves the total specific surface area and the micropore volume of the molecular sieve; comparing example 1 with comparative examples 1-2, the total specific surface area and micropore volume of example 1 are lower than those of example 1, which shows that Al-PLS-3 is treated with shikimic acid derivative acid for 30min, and compared with hydrochloric acid-ethanol solution and acetic acid treatment, the total specific surface area and micropore volume of the secondary molecular sieve are improved to a certain extent.

As can also be seen from Table 1, the external specific surface areas of the secondary molecular sieves of examples 1 to 3 are higher than 195m²·g^-1The percentage of the external specific surface area is higher than 48%, comparing examples 1-3 with Al-PLS-3, and the percentage of the external specific surface area of examples 1-3 with the external specific surface area is higher than Al-PLS-3, namely the original sample; this shows that Al-PLS-3 is treated with shikimic acid derivative acid for 30min, i.e. the acidification time is shortened, so that the percentage of the external specific surface area to the external specific surface area of the prepared secondary molecular sieve is increased, i.e. the treatment of shikimic acid derivative exposes more external specific surface area in the disordered stacking mode of the FER layer plate. Comparing example 1 with example 4, the percentage ratio of the external specific surface area to the external specific surface area of example 4 is higher than that of example 1, which shows that the external specific surface area and the percentage ratio of the external specific surface area of the molecular sieve are increased by performing acid treatment on the layered precursor Al-PLS-3 in the mixed solution of the shikimic acid derivative and geniposidic acid.

8. Determination of catalytic performance of secondary molecular sieve

The cleavage reaction of TIPB was carried out under atmospheric pressure in a fixed bed continuous flow microreactor. The reaction conditions were as follows: 0.1g of molecular sieve powder was put into a quartz tube having an inner diameter of 11mm under N₂Activating for 1h at 450 ℃ under the atmosphere. After activation, the temperature was adjusted to 350 ℃ and TIPB and N were added₂The mixed gas of (3) is reacted. The TIPB cleavage is a stepwise reaction which in turn produces Diisopropylbenzene (DIPB), cumene (IPB) and cumeneBenzene (BZ) as the main product. The mass space velocity (WHSV) of the reaction to TIPB was 2.16h^-1，N₂The flow rate is 15 mL/min^-1. The reaction product was collected by cold hydrazine in an ice water bath (273K). The acylation reaction of anisole and acetic anhydride is carried out in a round-bottom flask with a condensing tube; the operation method of the esterification reaction of ethanol and acetic acid is similar to the TIPB cracking reaction; all analyses of reactants and products were performed by gas chromatography, the chromatographic types: shimadzu 14B, FID, FFAP capillary column.

TABLE 2 results of samples catalyzing esterification of ethanol and acetic acid

As can be seen from Table 2, the catalytic conversion rate of the secondary molecular sieve prepared in examples 1-4 is higher than 59.5%, and the catalytic activity is higher than that of the precursor Al-PLS-3-60; comparing example 1 with comparative examples 1-2, the catalytic activity of example 1 is higher than that of comparative examples 1-2, which shows that the layered precursor Al-PLS-3 is treated with acid in the shikimic acid derivative solution for 30min, namely the acid treatment time is shortened, and the catalytic activity of the secondary molecular sieve is improved; comparing example 1 with example 4, the catalytic esterification conversion rate of example 4 is not much different from that of example 1, which shows that the acid treatment of the layered precursor Al-PLS-3 in the mixed solution of shikimic acid derivative and geniposidic acid has no obvious influence on the catalytic activity of the esterification reaction of ethanol and acetic acid.

FIG. 8 is a catalytic cracking reaction of secondary molecular sieves on TIPB. As can be seen from FIG. 8, the conversion of TIPB decreased gradually as WHSV increased, but the conversion of examples 1 and 4 was always higher than that of Al-PLS-3-60; comparing example 1 with comparative examples 1-2, the conversion rate of TIPB of example 1 is higher than that of comparative examples 1-2, which shows that the acid treatment of the layered precursor Al-PLS-3 in the shikimic acid derivative solution for 30min improves the catalytic cracking reaction of the secondary molecular sieve on TIPB, shortens the acid treatment time and ensures that the secondary molecular sieve has excellent catalytic performance; comparing example 1 with example 4, the conversion rate of the cleavage reaction of TIPB in example 4 is higher than that in example 1, which shows that the catalytic cleavage reaction of TIPB by the secondary molecular sieve is further improved by performing acid treatment on the layered precursor Al-PLS-3 in the mixed solution of shikimic acid derivative and geniposidic acid.

FIGS. 9, 10, and 11 show the catalytic rates of cracking reactions of secondary molecular sieves, p-Diisopropylbenzene (DIPB), cumene (IPB), and Benzene (BZ), respectively; the conversion rate of DIPB is gradually increased along with the increase of WHSV, but the catalytic cracking activity of the DIPB of the examples 1 and 4 and the comparative examples 1-2 is lower than that of a layered precursor Al-PLS-3-60, and the cracking capacity of the Isopropylbenzene (IPB) and the Benzene (BZ) is higher than that of the layered precursor Al-PLS-3-60; comparing example 1 with example 4, and the change trend of the catalytic cracking reaction of Diisopropylbenzene (DIPB) in example 1 and example 4 is close, which shows that the acid treatment of the layered precursor Al-PLS-3 in the mixed solution of shikimic acid derivative and geniposide makes the secondary molecular sieve have no obvious influence on the catalytic cracking reaction of Diisopropylbenzene (DIPB); in example 4, the cracking capacity of cumene (IPB) and Benzene (BZ) is higher than that of example 1, which shows that the layered precursor Al-PLS-3 is subjected to acid treatment in a mixed solution of shikimic acid derivatives and geniposidic acid for 30min, namely, the acidification treatment time is shortened, and the obtained secondary molecular sieve has higher selectivity on cumene (IPB) and Benzene (BZ), namely, has stronger cracking capacity; comparing example 1 with comparative examples 1-2, example 1 has higher cleavage capacity for cumene (IPB) and Benzene (BZ) than comparative examples 1-2, which shows that acid treatment of layered precursor Al-PLS-3 in a shikimic acid derivative solution improves the cleavage capacity of the secondary molecular sieve for cumene (IPB) and Benzene (BZ).

FIG. 12 shows the results of a Friedel-crafts acylation catalyzed by a secondary molecular sieve on anisole and acetic anhydride. As can be seen from FIG. 12, examples 1 and 4 have better catalytic activity for the Friedel-crafts acylation reaction of anisole and acetic anhydride, and compared with examples 1 and 4, example 4 has higher catalytic activity for the Friedel-crafts acylation reaction of anisole and acetic anhydride than example 1, which shows that the secondary molecular sieve obtained by carrying out acid treatment on the layered precursor Al-PLS-3 in the mixed solution of shikimic acid derivatives and geniposidic acid has better catalytic activity for the Friedel-crafts acylation reaction of anisole and acetic anhydride; comparing example 1 with comparative examples 1-2, the catalytic activity of example 1 for the catalytic Friedel-crafts acylation reaction of anisole and acetic anhydride is higher than that of comparative examples 1-2, which shows that the layered precursor Al-PLS-3 is treated by acid in the shikimic acid derivative solution for 30min, the acidification treatment time is shortened, and the catalytic activity of the secondary molecular sieve for the Friedel-crafts acylation reaction of anisole and acetic anhydride is improved.

9. Secondary molecular sieve pair CO₂Reforming to produce CH₄Determination of the catalytic reaction

A fixed bed reactor with the pipe diameter of 6mm is adopted to carry out reforming reaction under the normal pressure condition. After tabletting to 20-40 mesh granules, the catalyst was loaded in an amount of 0.1 g. Samples were taken at 50mL/min H before reaction₂Preactivate for 1h at 600 ℃ under purge, then reduce to the desired temperature for reaction. The reaction conditions are as follows: temperature 700 ℃ CO₂Flow rate of (2) is 20mL/min, CH₄The flow rate was 40mL/min, and samples were taken every 30 min. The reaction product of Chongqing Chuan instrument company (GC968 type) gas chromatograph is used for analysis, and the conversion rate of methane and carbon dioxide of a sample at 700 ℃ is measured.

Conversion (%) of methane ═ a₀-A₁)/A₀×100％

Wherein A is₀Is the amount of methane before reaction, mol; a. the₁Is the amount of methane after the reaction, mol.

FIG. 13 shows secondary molecular sieve vs. CO₂Reforming to produce CH₄Post catalytic CH₄The conversion of (a). As can be seen in FIG. 13, the conversion of methane in examples 1-4 is greater than 82.5%, comparing example 1 with example 4, and the secondary molecular sieves in examples 1 and 4 with CO₂Reforming to produce CH₄CH obtained by catalytic reaction₄The conversion rate of the precursor has no obvious difference, which shows that the layered precursor Al-PLS-3 is subjected to acid treatment in a mixed solution of shikimic acid derivatives and geniposidic acid to ensure that the secondary molecular sieve has CO pairing₂Reforming to produce CH₄The catalytic activity of the catalyst has no obvious influence; comparing example 1 with comparative examples 1-2, CH in example 1₄The conversion of (A) was higher than that of comparative examples 1-2, which shows that the layered precursor Al-PLS-3 was acid-treated in a shikimic acid derivative solution for 30min, improves the secondary molecular sieve pair CO₂Reforming to produce CH₄Catalytic activity of the catalytic reaction.

10. Determination of hydrothermal stability of secondary molecular sieve

This experiment employed N₂The molecular sieve is characterized and analyzed by an adsorption-desorption technology, and the test conditions are as follows in test example 2: 4. secondary molecular sieve N₂Measurement of adsorption-desorption curve "; and (3) measuring the external specific surface area and the total pore volume of the secondary molecular sieve before hydrothermal treatment and after hydrothermal treatment for 10d, and then calculating the retention rate of the external specific surface area and the total pore volume of the molecular sieve after hydrothermal treatment.

Fig. 14 is the external specific surface area of the secondary molecular sieve versus the total pore volume retention. As can be seen from FIG. 14, the retention rate of the external specific surface area after 10d of hydrothermal treatment of examples 1-3 is higher than 90.5%, the retention rate of the total pore volume is higher than 82.5%, the comparative examples 1 and 1-2, the retention rate of the external specific surface area and the total pore volume of example 1 are higher than that of comparative examples 1-2, which shows that the acid treatment of the layered precursor Al-PLS-3 in the shikimic acid derivative solution for 30min improves the hydrothermal stability of the secondary molecular sieve, i.e. the hydrothermal stability is better in a shorter acid treatment time; comparing example 1 with example 4, the external specific surface area and the total pore volume retention rate of example 4 are higher than those of example 1, which shows that the hydrothermal stability of the secondary molecular sieve is further improved by carrying out acid treatment on the layered precursor Al-PLS-3 in the mixed solution of shikimic acid derivative and geniposidic acid.

Conventional operations in the operation steps of the present invention are well known to those skilled in the art and will not be described herein.

The above embodiments are merely illustrative, and not restrictive, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, all equivalent technical solutions also belong to the scope of the present invention, and the protection scope of the present invention should be defined by the claims.