Pd-based moving catalyst as well as preparation method and application thereof

Abstract

The invention discloses a Pd-based moving catalyst and a preparation method and application thereof.The preparation method comprises the steps that S1, a silicon source substance, a template agent and a microstructure regulating agent are added into an anhydrous solvent, ultrasonic treatment and stirring are conducted, and an organic phase is obtained; s2, dissolving an alkali substance in distilled water, and performing ultrasonic treatment and stirring to obtain a water phase; s3, dropwise adding the water phase into the organic phase, stirring, standing for reaction, centrifuging, washing and calcining to obtain a carrier; s4, dispersing the carrier in distilled water, and stirring to obtain a suspension; and S5, ultrasonically dissolving a Pd precursor in distilled water, adding the turbid liquid, stirring, dropwise adding an alkali solution to adjust the pH value, stirring and reacting in an alkaline environment, centrifuging to obtain a crude product, washing to be neutral, and drying to obtain the palladium-based moving catalyst. The Pd-based moving catalyst disclosed by the invention has high activity in an HBIW hydrogenolysis debenzylation reaction.

Description

Technical Field

[0001] The present invention relates to the technical field related to catalysts, and more specifically, to a Pd-based mobile catalyst and a preparation method and application thereof. Background Art

[0002] It has been confirmed by many scientists that metal species act as active sites in many heterogeneous catalysts. The active sites in such catalysts often remain in a static state during the catalytic reaction, passively adsorbing and converting the reaction substrates, which are often simple compounds with small molecular weights. This is also the case with Pd-based catalysts. Their static properties limit the catalytic conversion of some complex multidimensional organic molecules, which often have more sites to be reacted and special structures. Since they passively wait for the substrate to come to adsorb and react during the reaction, the catalytic efficiency will be greatly reduced.

[0003] Benzyl is one of the most widely used protecting groups in fine chemical synthesis and is often used to protect amine groups, hydroxyl groups, etc. The introduction of benzyl groups is usually easy, but sometimes its removal is a thorny problem, such as the removal of N-benzyl groups. Catalytic hydrogenolysis debenzylation reactions are crucial in organic synthesis and pharmaceuticals, but achieving high yields, atom efficiency, and cost-effectiveness is challenging, especially for multidimensional complex molecules like hexabenzylhexaazaisowurtzitane (HBIW). HBIW is an important precursor for the synthesis of the typical energetic material hexanitrohexaazaisowurtzitane (HNIW or CL-20), and its hydrogenolysis of N-benzyl groups becomes a key step in the synthesis of CL-20. However, the six benzyl groups, low solubility, and complex multi-ring structure of HBIW require efficient catalysts that must operate at mild temperatures to maintain its unique cage structure. Although various static site catalysts exist to choose from, they generally show limited activity, resulting in low yields and high costs, and further improvements are urgently needed. Summary of the invention

[0004] An object of the present invention is to provide a Pd-based mobile catalyst and a preparation method and application thereof, wherein the Pd-based mobile catalyst has high activity in the hydrogenolysis of HBIW.

[0005] In order to achieve these purposes and other advantages of the present invention, according to one aspect of the present invention, the present invention provides a method for preparing a Pd-based mobile catalyst, comprising: S1: adding a silicon source material, a template agent, and a micro-morphology regulating agent to an anhydrous solvent, ultrasonically and stirring, to obtain an organic phase; S2: dissolving an alkaline material in distilled water, ultrasonically and stirring, to obtain an aqueous phase; S3: dropping the aqueous phase into the organic phase, stirring, standing to react, centrifuging, washing, and calcining to obtain a carrier; S4: dispersing the carrier in distilled water, stirring to obtain a suspension; S5: ultrasonically dissolving a Pd precursor in distilled water, adding the above suspension and stirring, dropping an alkaline solution to adjust the pH, stirring the reaction under an alkaline environment, centrifuging to obtain a crude product, washing to neutrality, and drying to obtain a palladium-based mobile catalyst.

[0006] Furthermore, the silicon source material includes any one or more of methyl orthosilicate, tetraethyl orthosilicate, (3-aminopropyl)triethoxysilane, and (3-aminopropyl)trimethoxysilane, the template includes any one or more of hexadecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, octadecyltrimethylammonium chloride, and octadecyltrimethylammonium bromide, and the micromorphology regulator includes any one or more of toluene, xylene, and ethylbenzene; the molar ratio of the template to the silicon source is 3~7:10, and the volume ratio of the micromorphology regulator to the silicon source material is 6~14:3.

[0007] Furthermore, the anhydrous solvent includes any one or more of anhydrous methanol, anhydrous ethanol, anhydrous acetone, and anhydrous ethyl acetate, and the volume ratio of the anhydrous solvent to the silicon source material is 120-150:1.

[0008] Furthermore, the alkaline substance includes one or more of concentrated ammonia water, NaOH, and KOH, and the concentration of the alkaline solution is 0.3-1.7 mol / L.

[0009] Furthermore, in S3, the detergent is a mixture of anhydrous acetone and anhydrous ethanol, and the volume ratio of anhydrous acetone to anhydrous ethanol in the detergent is 1-4:5; the calcination conditions include: the calcination atmosphere is air, the calcination temperature is 500-700°C, the heating rate is 5-20°C / min, and the calcination time is 5-10 h.

[0010] Furthermore, the Pd precursor is any one of ammonium palladium (II) chloride, sodium palladium (II) chloride, and potassium palladium (II) chloride, and the concentration of the solution after the Pd precursor is dissolved in distilled water is 0.001~0.006M.

[0011] Furthermore, in S5, the pH is adjusted using one or more of an ammonia solution, a NaOH solution, a NaHCO3 solution, and a KOH solution.

[0012] Furthermore, in S5, the reaction temperature is 25-55°C, the reaction time is 3-8 h, and the washing solvent is an aqueous solution of alcohol, wherein the alcohol includes one or both of methanol and ethanol.

[0013] According to another aspect of the present invention, a Pd-based mobile catalyst is also provided, which is prepared by the preparation method of the Pd-based mobile catalyst.

[0014] According to another aspect of the present invention, there is also provided the use of the Pd-based mobile catalyst in catalyzing the debenzylation of hexabenzylhexaazaisowurtzitane.

[0015] The present invention has at least the following beneficial effects: The silica carrier prepared by the present invention has a macroporous-mesoporous-microporous multi-level pore structure and a large specific surface area, which can produce a strong metal-carrier interaction, ensure that the Pd active species are attached back to the carrier after the reaction, reduce the loss rate of precious metal palladium, and facilitate repeated use and stability. The catalyst of the present invention has a special shape that can enhance the mass transfer effect of the reaction, make the substrate and the active site contact more fully, accelerate the reaction rate, and improve production efficiency. The present invention uses ultra-small, uniformly dispersed and mobile Pd active sites carefully designed on the carrier to make it a Pd-based mobile catalyst, showing high activity in the HBIW hydrogenolysis benzyl reaction, overcoming the problem of insufficient activity of traditional catalysts for complex molecules, helping to improve the yield of the target product, and has good application prospects.

[0016] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a scanning electron microscope photograph of the carrier V-SiO2 prepared in Example 1; Figure 2 This is a cross-sectional scanning electron microscope photograph of the carrier V-SiO2 prepared in Example 2; Figure 3 The nitrogen isothermal adsorption-desorption curve of the carrier V-SiO2 prepared in Example 3; Figure 4 This is the micro-mesopore pore size distribution curve of the carrier V-SiO2 prepared in Example 3; Figure 5 This is a high-magnification transmission electron microscope photo of the catalyst 6Pd(OH)2 / V-SiO2-4 prepared in Example 4; Figure 6 This is the element distribution diagram of the catalyst 6Pd(OH)2 / V-SiO2-4 prepared in Example 4; Figure 7 This is a scanning electron microscope photograph of the carrier SiO2 sphere prepared in Comparative Example 1; Figure 8 The chemical reaction equation for the hydrogenolysis-debenzylacetylation of HBIW is shown in FIG. DETAILED DESCRIPTION

[0018] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0019] It should be understood that the terms such as "having", "including" and "comprising" used in the embodiments of the present application do not exclude the existence or addition of one or more other elements or their combinations. All directional indications (such as up, down, left, right, front, back...) in the embodiments of the present application are only used to explain the relative position relationship, movement, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly. When an element is referred to as "fixed on" or "set on" another element, it can be directly on the other element or there may be a centering element at the same time. When an element is referred to as "connecting" another element, it can be directly connected to another element or it can be indirectly connected to another element through a centering element. The description of "first", "second", etc. in the embodiments of the present application is only for descriptive purposes, and cannot be understood as indicating or implying its relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" can explicitly or implicitly include at least one of the features.

[0020] The prepared spherical silica carrier has an obvious V-shaped pore structure, and its abbreviation is V-SiO2. The spherical silica carrier used in the comparative example is abbreviated as SiO2.

[0021] <Example 1> The preparation method of 3Pd(OH)2 / V-SiO2-1 comprises the following steps: S1. Dissolve 180 μL tetraethyl orthosilicate, 150 mg hexadecyltrimethylammonium bromide and 500 μL toluene in 25 mL anhydrous ethanol, sonicate for 10 min at a power of 200 W, stir for 10 min at a speed of 700 r / min, and fully dissolve to form a transparent and uniform organic phase. S2. Mix 1 mL of concentrated ammonia with 26 mL of distilled water to form a homogeneous aqueous phase.

[0022] S3, dripping the aqueous phase into the organic phase at a rate of 0.3 mL / s, stirring to form a transparent liquid, stirring time for 30 min, stirring speed of 500 r / min, standing for reaction for 3 h, collecting the product by centrifugation, washing three times with a detergent consisting of anhydrous acetone and anhydrous ethanol in a volume ratio of 2:5, and vacuum drying in an oven at 60 °C overnight, calcining to obtain a carrier, wherein the calcination conditions are: atmosphere is air, calcination temperature is 550 °C, heating rate is 15 °C / min, and calcination time is 6 h; S4, 0.5 g of the carrier was evenly dispersed in 70 mL of distilled water, and stirred to obtain a suspension. The stirring time was 30 min and the stirring speed was 500 r / min; S5. Dissolve 0.05 g of sodium palladium (II) chloride in 30 mL of distilled water by ultrasonic. Add the above suspension and stir. After a certain period of time, add a 10 wt% NaOH solution at a rate of 0.2 mL / s. Adjust the pH to about 9. Stir and react for 5 h under this environment. The reaction temperature is 40 °C. After the reaction, the mixture is centrifuged to obtain a crude product. The centrifugal speed is 10000 r / min. The washing solvent is a 1:1 solution of water: ethanol. After the crude product is washed to neutral, it is dried to obtain a palladium-based mobile catalyst.

[0023] <Example 2> The preparation method of 3Pd(OH)2 / V-SiO2-2 comprises the following steps: S1. Dissolve 180 μL of methyl orthosilicate, 160 mg of hexadecyltrimethylammonium bromide and 600 μL of toluene in 30 mL of anhydrous methanol, ultrasonicate for 15 min at an ultrasonic power of 200 W, stir for 10 min at a stirring speed of 700 r / min, and fully dissolve to form a transparent and uniform organic phase; S2. Mix 1 mL of concentrated ammonia water with 30 mL of distilled water to form a homogeneous aqueous phase.

[0024] S3, dripping the aqueous phase into the organic phase at a rate of 0.3 mL / s, stirring to form a transparent liquid, stirring time for 30 min, stirring speed of 500 r / min, standing for 4 h, collecting the product by centrifugation, washing three times with a detergent consisting of anhydrous acetone and anhydrous ethanol in a volume ratio of 2:5, and vacuum drying in an oven at 60 °C overnight, calcining to obtain a carrier, wherein the calcination conditions are: atmosphere is air, calcination temperature is 550 °C, heating rate is 15 °C / min, and calcination time is 6 h; S4, 0.5 g of the carrier was evenly dispersed in 80 mL of distilled water, and stirred to obtain a suspension. The stirring time was 30 min and the stirring speed was 500 r / min; S5. Dissolve 0.05 g of sodium palladium (II) chloride in 30 mL of distilled water by ultrasonic. Add the above suspension and stir. After a certain period of time, add a 10 wt% NaOH solution at a rate of 0.2 mL / s. Adjust the pH to about 10. Stir and react for 5 h under this environment. The reaction temperature is 40 °C. After the reaction, the mixture is centrifuged to obtain a crude product. The centrifugal speed is 10000 r / min. The washing solvent is a 1:1 solution of water: ethanol. After the crude product is washed to neutral, it is dried to obtain a palladium-based mobile catalyst.

[0025] <Example 3> The preparation method of 6Pd(OH)2 / V-SiO2-3 comprises the following steps: S1. Dissolve 180 μL tetraethyl orthosilicate, 150 mg hexadecyltrimethylammonium bromide and 500 μL toluene in 30 mL anhydrous ethanol, ultrasonicate for 10 min at an ultrasonic power of 200 W, stir for 10 min at a stirring speed of 700 r / min, and fully dissolve to form a transparent and uniform organic phase; S2. Mix 1 mL of concentrated ammonia water with 30 mL of distilled water to form a homogeneous aqueous phase.

[0026] S3, dripping the aqueous phase into the organic phase at a rate of 0.3 mL / s, stirring to form a transparent liquid, stirring time for 30 min, stirring speed of 500 r / min, standing for 3 h, collecting the product by centrifugation, washing three times with a detergent consisting of anhydrous acetone and anhydrous ethanol in a volume ratio of 2:5, and vacuum drying in an oven at 60 °C overnight, calcining to obtain a carrier, wherein the calcination conditions are: atmosphere is air, calcination temperature is 500 °C, heating rate is 15 °C / min, and calcination time is 6 h; S4, 0.5 g of the carrier was evenly dispersed in 70 mL of distilled water, and stirred to obtain a suspension. The stirring time was 30 min and the stirring speed was 800 r / min; S5. Dissolve 0.1 g of sodium palladium (II) chloride in 50 mL of distilled water by ultrasonic. Add the above suspension and stir. After a certain period of time, add a 10 wt% NaOH solution at a rate of 0.5 mL / s. Adjust the pH to about 10. Stir and react for 8 h under this environment. The reaction temperature is 40 °C. After the reaction, the mixture is centrifuged to obtain a crude product. The centrifugal speed is 10000 r / min. The washing solvent is a 1:1 solution of water: ethanol. After the crude product is washed to neutral, it is dried to obtain a palladium-based mobile catalyst.

[0027] <Example 4> The preparation method of 6Pd(OH)2 / V-SiO2-4 comprises the following steps: S1. Dissolve 180 μL tetraethyl orthosilicate, 170 mg hexadecyltrimethylammonium chloride and 700 μL toluene in 30 mL anhydrous ethanol, ultrasonicate for 10 min at an ultrasonic power of 300 W, stir for 10 min at a stirring speed of 700 r / min, and fully dissolve to form a transparent and uniform organic phase; S2, 1.2 mL of concentrated ammonia water and 35 mL of distilled water were mixed to form a homogeneous aqueous phase.

[0028] S3, dripping the aqueous phase into the organic phase at a rate of 0.4 mL / s, stirring to form a transparent liquid, stirring time for 40 min, stirring speed of 500 r / min, standing for 5 h, collecting the product by centrifugation, washing three times with a detergent consisting of anhydrous acetone and anhydrous ethanol in a volume ratio of 2:5, and vacuum drying in an oven at 60 °C overnight, calcining to obtain a carrier, wherein the calcination conditions are: atmosphere is air, calcination temperature is 600 °C, heating rate is 15 °C / min, and calcination time is 6 h; S4, 0.5 g of the carrier was evenly dispersed in 70 mL of distilled water, and stirred to obtain a suspension. The stirring time was 30 min and the stirring speed was 800 r / min; S5. Dissolve 0.1 g of sodium palladium (II) chloride in 50 mL of distilled water by ultrasonic. Add the above suspension and stir. After a certain period of time, add a 10 wt% NaOH solution at a rate of 0.5 mL / s. Adjust the pH to about 10. Stir and react for 6 h under this environment. The reaction temperature is 50 °C. After the reaction, the mixture is centrifuged to obtain a crude product. The centrifugal speed is 10000 r / min. The washing solvent is a 1:1 solution of water: ethanol. After the crude product is washed to neutral, it is dried to obtain a palladium-based mobile catalyst.

[0029] <Comparative Example 1> The preparation method of 6Pd(OH)2 / SiO2 comprises the following steps: S1. Dissolve 180 μL tetraethyl orthosilicate in 30 mL anhydrous ethanol, ultrasonicate for 10 min at an ultrasonic power of 300 W, stir for 10 min at a stirring speed of 700 r / min, and fully dissolve to form a transparent and uniform organic phase; S2, 1.2 mL of concentrated ammonia water and 35 mL of distilled water were mixed to form a homogeneous aqueous phase.

[0030] S3, dripping the aqueous phase into the organic phase at a rate of 0.4 mL / s, stirring to form a transparent liquid, stirring time for 40 min, stirring speed of 500 r / min, standing for 5 h, collecting the product by centrifugation, washing three times with a detergent consisting of anhydrous acetone and anhydrous ethanol in a volume ratio of 2:5, and vacuum drying in an oven at 60 °C overnight, calcining to obtain a carrier, wherein the calcination conditions are: atmosphere is air, calcination temperature is 600 °C, heating rate is 15 °C / min, and calcination time is 6 h; S4, 0.5 g of the carrier was evenly dispersed in 70 mL of distilled water, and stirred to obtain a suspension. The stirring time was 30 min and the stirring speed was 800 r / min; S5. Dissolve 0.1 g of sodium palladium (II) chloride in 50 mL of distilled water by ultrasonic. Add the above suspension and stir. After a certain period of time, add a 10 wt% NaOH solution at a rate of 0.5 mL / s. Adjust the pH to about 10. Stir and react for 6 h under this environment. The reaction temperature is 50 °C. After the reaction, the mixture is centrifuged to obtain a crude product. The centrifugal speed is 10000 r / min. The washing solvent is a 1:1 solution of water: ethanol. After the crude product is washed to neutral, it is dried to obtain a palladium-based mobile catalyst.

[0031] <Comparative Example 2> 10Pd(OH)2 / C was commercially available.

[0032] <Comparative Example 3> The support was replaced to obtain 3Pd(OH)2 / diatomaceous earth.

[0033] <Comparative Example 4> The support was replaced to obtain 5Pd(OH)2 / diatomaceous earth.

[0034] <Comparative Example 5> Compared with Example 1, the active material was replaced to obtain 3Pd / V-SiO2-1.

[0035] <Comparative Example 6> Compared with Example 1, the active species were replaced to obtain 3Pd / V-SiO2-1.

[0036] <Carrier Performance Test> The BET specific surface area and the pore volume under standard conditions of the carriers in Examples 1 to 4 and Comparative Example 1 were respectively detected, and the results are shown in Table 1 below: Table 1 Specific surface area and pore volume of each group of carriers According to the data in Table 1, the specific surface area and pore volume of the carriers prepared in Examples 1 to 4 are both very high, indicating that the carriers prepared in Examples 1 to 4 have the characteristics of large specific surface area and large pore volume (see also Figure 1-Figure 2 ), which is beneficial to the mass transfer of Pd active sites for loading and catalytic process. However, since the support prepared in Comparative Example 1 does not add template agent and micromorphology regulator, its specific surface area and pore volume are very low (see Figure 7 ), which will reduce the catalyst performance.

[0037] Depend on Figure 3 It can be seen that the isotherm is a mixed I / IV type with an H4 type hysteresis loop. At the same time, it has a high adsorption volume at low P / P0 and the isotherm rises in the high P / P0 region, indicating that there is a multi-level pore structure of macropores-mesopores-micropores in the material.

[0038] Depend on Figure 4 It can be seen that within the pore size range of 0.5-2 nm, there are micropores distributed, that is, the carrier of Example 3 has a large specific surface area. At the same time, the synergistic effect of different pore sizes can provide a strong metal-carrier interaction and improve the catalytic efficiency.

[0039] Depend on Figure 5 It can be seen that in the catalyst 6Pd(OH)2 / V-SiO2-4 prepared in Example 4, Pd(OH)2 nanoparticles are uniformly loaded on the V-SiO2-4 carrier.

[0040] Depend on Figure 6 It can be seen that in the catalyst 6Pd(OH)2 / V-SiO2-4 prepared in Example 4, the Pd element is evenly distributed, indicating that the Pd species is successfully and evenly loaded.

[0041] <Catalyst activity performance test 1> The activity of the obtained catalyst was evaluated by hydrogenolysis of HBIW as a probe reaction. The reaction equation is as follows: Figure 8 As shown. The specific test conditions are as follows: 50 g of HBIW, 0.85 g of catalyst, 100 mL of N, N-dimethylformamide (DMF), 50 mL of acetic anhydride (Ac2O), and 1 mL of PhBr are mixed, evacuated, replaced with hydrogen 3 to 5 times, and then hydrogen is introduced and stirred. The mixture is reacted at room temperature and pressure until a solid hydrogenolysis product is precipitated. The temperature is raised to 40°C and the reaction is continued. The total reaction time is about 20 h. After the reaction is completed, the solid obtained by filtration is washed and dried to obtain a crude hydrogenolysis debenzylation product. The activity data of each group of catalysts in the HBIW hydrogenolysis debenzylation reaction are detected, wherein the catalysts are the Pd-based mobile catalysts prepared in Examples 1 to 4, and Pd / HBIW is the mass fraction of Pd in ​​the HBIW system. The results are shown in Table 2 below: Table 2 Activity data of each group of catalysts According to the data in Table 2, the Pd-based mobile catalysts prepared by Examples 1 to 4 show excellent catalytic activity in the hydrogenolysis debenzylation acetylation reaction of HBIW, far exceeding similar catalysts (Comparative Examples 1-4), and can greatly improve the stability of Pd active species on the carrier and reduce the shedding of Pd. The performance of the catalyst prepared in Comparative Example 1 is greatly reduced, and the Pd metal falls off significantly during the catalytic process, and the stability is poor. Comparative Examples 2-4 replace different carriers, and the performance of the resulting catalysts is far inferior to that of the catalysts in Examples 1 to 4. 3Pd / V-SiO2-1 in Comparative Example 5 and 6Pd / V-SiO2-1 in Comparative Example 6 are common comparative catalysts loaded with Pd single substance, and their active sites are static, and neither can cause the catalytic reaction to proceed.

[0042] <Catalyst activity performance test 2> The activity of 6Pd(OH)2 / V-SiO2-4 catalyst was evaluated by hydrogenolysis debenzylation of HBIW as a probe reaction to explore the mobility of the catalyst. The specific test conditions are as follows: 50 g of HBIW, 0.85 g of catalyst, 100 mL of N, N-dimethylformamide (DMF), 50 mL of acetic anhydride (Ac2O), and 1 mL of PhBr were mixed, vacuumed, replaced with hydrogen 3 to 5 times, and then hydrogen was introduced and stirred. The reaction was carried out at room temperature and pressure until solid hydrogenolysis products were precipitated, and then the temperature was raised to 40°C and the reaction was continued. The total reaction time was set to 1 h, 2 h, 5 h, 9 h, 13 h, and 20 h, respectively. After the reaction, the solids filtered out were washed and dried, and the Pd content of the catalyst after the HBIW hydrogenolysis debenzylation reaction in each period was detected, where Pd / HBIW is the mass fraction of Pd in ​​the HBIW system. The results are shown in Table 3 below: Table 3 Pd content of catalyst recovered at different time periods According to the data in Table 3, the Pd content on the recovered catalyst of the Pd-based mobile catalyst 6Pd(OH)2 / V-SiO2-4 prepared in Example 4 first decreases and then increases during the hydrogenolysis debenzylacetylation reaction of HBIW, indicating that the active site Pd species on the catalyst is in a mobile state during the catalytic reaction (indicating that Example 4 successfully completed the preparation of the mobile catalyst), revealing the reason for its high catalytic activity. The details of the state are as follows: the Pd species continuously leaves the carrier in the initial stage of the reaction to actively adsorb and react with the substrate, and gradually returns to the carrier after the reaction.

[0043] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A method for preparing a Pd-based mobile catalyst, characterized in that: include: S1: adding silicon source material, template agent and micromorphology control agent into an anhydrous solvent, ultrasonicating and stirring to obtain an organic phase; S2: dissolving the alkaline substance in distilled water, ultrasonicating and stirring to obtain an aqueous phase; S3: dropping the aqueous phase into the organic phase, stirring, standing for reaction, centrifuging, washing, and calcining to obtain a carrier; S4: dispersing the carrier in distilled water and stirring to obtain a suspension; S5: ultrasonically dissolve the Pd precursor in distilled water, add the above suspension and stir, drop an alkaline solution to adjust the pH, stir the reaction in an alkaline environment, centrifuge to obtain a crude product, wash to neutrality, and dry to obtain a palladium-based mobile catalyst.

2. The method for preparing the Pd-based mobile catalyst according to claim 1, characterized in that: The silicon source material includes any one or more of methyl orthosilicate, tetraethyl orthosilicate, (3-aminopropyl) triethoxysilane, (3-aminopropyl) trimethoxysilane, the template includes any one or more of hexadecyl trimethyl ammonium bromide, hexadecyl trimethyl ammonium chloride, octadecyl trimethyl ammonium chloride, octadecyl trimethyl ammonium bromide, and the micro-morphology control agent includes any one or more of toluene, xylene, and ethylbenzene; The molar ratio of the template to the silicon source is 3-7:10, and the volume ratio of the micro-morphology control agent to the silicon source is 6-14:

3.

3. The method for preparing the Pd-based mobile catalyst according to claim 1, characterized in that: The anhydrous solvent includes any one or more of anhydrous methanol, anhydrous ethanol, anhydrous acetone, and anhydrous ethyl acetate, and the volume ratio of the anhydrous solvent to the silicon source material is 120-150:

1.

4. The method for preparing the Pd-based mobile catalyst according to claim 1, characterized in that: The alkaline substance includes one or more of concentrated ammonia water, NaOH, and KOH, and the concentration of the alkaline solution is 0.3-1.7 mol / L.

5. The method for preparing the Pd-based mobile catalyst according to claim 1, characterized in that: In S3, the detergent is a mixture of anhydrous acetone and anhydrous ethanol, and the volume ratio of anhydrous acetone to anhydrous ethanol in the detergent is 1-4:5; The calcination conditions include: the calcination atmosphere is air, the calcination temperature is 500-700 °C, the heating rate is 5-20 °C / min, and the calcination time is 5-10 h.

6. The method for preparing the Pd-based mobile catalyst according to claim 1, characterized in that: The Pd precursor is any one of ammonium palladium (II) chloride, sodium palladium (II) chloride, and potassium palladium (II) chloride, and the concentration of the solution after the Pd precursor is dissolved in distilled water is 0.001-0.006 M.

7. The method for preparing the Pd-based mobile catalyst according to claim 1, characterized in that: In S5, the pH is adjusted using one or more of an aqueous ammonia solution, a NaOH solution, a NaHCO3 solution, and a KOH solution.

8. The method for preparing the Pd-based mobile catalyst according to claim 1, characterized in that: In the S5, the reaction temperature is 25-55°C, the reaction time is 3-8 hours, and the washing solvent is an aqueous solution of alcohol, wherein the alcohol includes one or both of methanol and ethanol.

9. A Pd-based mobile catalyst, characterized in that The catalyst is prepared by the method for preparing the Pd-based mobile catalyst according to any one of claims 1 to 8.

10. Use of the Pd-based mobile catalyst according to claim 9 in catalyzing the debenzylation of hexabenzylhexaazaisowurtzitane.

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