A nitrogen-fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst, preparation and application thereof

Abstract

The application discloses a nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst and a preparation and application thereof. The catalyst is prepared by the following steps: (1) preparing a fluorine and nitrogen co-doped titanium dioxide carrier; (2) preparing a precursor solution of palladium and zirconium; (3) mixing the fluorine and nitrogen co-doped titanium dioxide carrier and deionized water, stirring to form a uniform slurry, then sequentially adding the precursor solution of palladium and zirconium, simultaneously adding a dispersing agent to stir and stabilize, adjusting the pH value to be greater than 10.0 after heating and stirring, and continuously stirring for 1-2 hours; performing suction filtration on the suspension, washing, vacuum drying, and then reducing under an H2 atmosphere to obtain the catalyst. The application provides application of the nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst in a TAIW synthesis reaction of HBIW continuous hydrogenolysis debenzylization, and the catalyst has high reaction activity, yield and stability, reduces the use amount of the noble metal palladium, and can effectively reduce production cost.

Description

(I) TECHNICAL FIELD

[0001] The present application relates to a nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst, its preparation and application in C-N hydrogenolysis reaction. (II) BACKGROUND

[0002] C-N bond is one of the most common inert bonds in organic compounds. Due to the high dissociation energy of C-N bond (for example, 102.6 kcal / mol for aniline), strong coordination ability, and poor leaving ability of -NH2 group, the cleavage of C-N bond, especially Csp 2 -N bond, is still one of the great challenges in chemical transformation. The benzyl protection of heterocyclic nitrogen is often used in the fields of organic synthesis, pharmaceutical and energetic material synthesis, and then the deprotection, i.e. debenzylation, is encountered.

[0003] Catalytic hydrogenolysis is one of the most popular methods for removing benzyl of benzylamine compounds, which has the characteristics of mild conditions (room temperature and normal pressure), high conversion rate, clean product, and has been widely used in fine chemical industry. In the catalytic hydrogenolysis of N-benzyl, non-homogeneous supported palladium catalyst is most widely used in the catalytic hydrogenolysis of N-benzyl. However, in practical application, some major problems often occur, such as low yield of some special debenzylation reactions, high loading and dosage of noble metal, poor stability, and side reactions, etc. In addition, the product of N-benzyl hydrogenolysis is a strong alkaline amine, which can deactivate the supported noble metal catalyst, so it is necessary to increase the dosage of the catalyst or add acid to complete the reaction.

[0004] In recent years, many scientists have conducted a lot of research in carrier modification and active component modification, such as forming bimetallic, metal alloy or mixed metal oxide with promoters and active phase. Using transition metal as a metal additive to modify palladium-based catalyst is an effective method to reduce the content of palladium and improve the catalytic performance at the same time. However, the current research on C-N hydrogenolysis is still very few. (III) SUMMARY

[0005] The first technical problem to be solved by the present application is to provide a preparation method of a nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst.

[0006] The second technical problem to be solved by the present application is to provide a nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst.

[0007] The third technical problem to be solved by the present application is to provide the application of the nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst in C-N hydrogenolysis reaction.

[0008] To solve the above technical problems, the present application adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a method for preparing a nitrogen-fluorine co-doped titanium dioxide-supported palladium-zirconium bimetallic catalyst, the preparation method being as follows:

[0010] (1) First, an appropriate amount of ammonium fluoride is added to a mixed solvent of ethanol and deionized water as a source of nitrogen and fluorine, and an appropriate amount of acidic solution is added to adjust the pH value of the solution to 4-5 to shorten the gelation time and generate a transparent solution. Under continuous magnetic stirring, an appropriate amount of titanium-containing organic matter is added to the solution and stirred for 2-4 hours to form a transparent and uniform mixture, which is then aged at room temperature for 12-24 hours until a transparent gel is formed. Thereafter, the obtained gel is placed in a vacuum drying oven at 60-90°C for 8-12 hours and then ground with an agate mortar to obtain a dry gel powder. Finally, the dry gel powder is placed in a muffle furnace and calcined at 200-500°C for 2-4 hours and cooled to room temperature to obtain a fluorine-nitrogen co-doped titanium dioxide carrier, which is denoted as TiO2-x%N,F, where x%=n 氟化铵 / n Ti × 100% = 2-4%, where n Ti It refers to the number of moles of Ti contained in titanium-containing organic matter;

[0011] (2) Weighing a certain amount of palladium-containing compound and zirconium-containing compound and dissolving them in an appropriate amount of deionized water to prepare palladium and zirconium precursor solutions, respectively;

[0012] (3) taking a certain amount of the fluorine-nitrogen co-doped titanium dioxide carrier prepared in step (1) and mixing it with deionized water, stirring to form a uniform slurry, and then adding the palladium and zirconium precursor solutions obtained in step (2) in sequence, and adding a dispersant to stir stably, heating to 60-80°C and keeping stirring for 4-6 hours; slowly adding an aqueous solution of an alkaline substance to the above suspension, adjusting the pH value to greater than 10.0, and continuing to stir for 1-2 hours; filtering the above suspension, and washing with deionized water until the pH of the filtrate is neutral, and the obtained sample is vacuum dried and then reduced under a H2 atmosphere to obtain the desired catalyst;

[0013] The theoretical loading amount of Pd in ​​the nitrogen-fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst is 5-10%, and the theoretical loading amount of Pd is m Pd / (m Pd +m ZrO2 +m 氮氟改性二氧化钛载体 )×100%, theoretical loading of Zr=m Zr / (m Pd +m ZrO2 +m 氮氟改性二氧化钛载体 )×100%, the molar ratio of palladium to zirconium is 7:(1~3), where m Pd Represents the mass of palladium contained in the palladium precursor solution, mZrO2 represents the mass of ZrO2 obtained by converting the mass of Zr contained in the precursor solution of zirconium.

[0014] Preferably, in step (1), the titanium-containing organic compound is at least one of tetraethyl titanate, tetraisopropyl titanate, and tetrabutyl titanate.

[0015] Preferably, in step (1), the volume ratio of the titanium-containing organic compound, ethanol, and water is 2-10:50:2-10.

[0016] Preferably, in step (1), the acidic solution is a 5-10wt% acetic acid or hydrochloric acid solution.

[0017] Preferably, in step (1), the calcination temperature is 300-400°C, more preferably 400°C.

[0018] Preferably, in step (2), the palladium compound is at least one of palladium chloride, sodium tetrachloropalladate, palladium acetate, and palladium nitrate.

[0019] Preferably, in step (2), the zirconium compound is at least one of zirconium chloride, zirconium nitrate, zirconium oxychloride, zirconium acetate, and zirconium n-propyl alcohol.

[0020] Preferably, in step (2), the dispersant is at least one of polyethylene glycol, polyvinylpyrrolidone, and ethylenediamine. The amount of the dispersant is 5-20% of the mass of the catalyst, where the mass of the catalyst = m Pd +m ZrO2 +m 氮氟改性二氧化钛载体 .

[0021] Preferably, in step (3), the aqueous alkaline solution is a 5-10wt% ammonia or NaOH solution.

[0022] Preferably, in step (3), the vacuum drying temperature is 80-110°C, and the vacuum drying time is 8-24h.

[0023] Preferably, in step (3), the reduction conditions are 100-400°C under a hydrogen atmosphere for 1-4h.

[0024] In a second aspect, the present application provides a nitrogen-fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst prepared by the method according to the first aspect.

[0025] In a third aspect, the present application provides an application of the nitrogen-fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst in the synthesis of TAIW by continuous debenzylation of hexabenzylhexaazaisowurtzitane (HBIW).

[0026] The application includes the following specific steps:

[0027] (1) The first step hydrogenolysis reaction takes HBIW as raw material (hereinafter referred to as HBIW hydrogenolysis reaction), and the specific operation process is as follows: HBIW, DMF, PhBr, nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst and Ac2O are sequentially added into a reaction kettle, and then continuous hydrogenation reaction is carried out at 25-40℃, 0.4-0.6 MPa hydrogen pressure and stirring conditions for 12-24h, the obtained reaction liquid is filtered to remove the filtrate, and the filter cake is dried to obtain a solid containing target product TADBIW and catalyst; in the calculation of the yield of the first step, the yield=(the mass of gray-white solid-catalyst consumption) / HBIW input amount;

[0028] (2) The second step hydrogenolysis reaction takes TADBIW as raw material (hereinafter referred to as TADBIW hydrogenolysis reaction), and the specific steps are as follows: the solid containing TADBIW and catalyst obtained in the first step hydrogenolysis reaction is added into a reaction kettle together with appropriate amount of acetic acid, and then acid washing is carried out at 60-70℃ for 1-4h, then nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst and deionized water are sequentially added, and then continuous hydrogenation reaction is carried out at 40-70℃, 1.5-3 MPa hydrogen pressure and stirring conditions for 12-24h, then filtration is carried out, and the obtained black solid is the catalyst, and the required product TAIW is dissolved in the filtrate. The second step hydrogenation product is subjected to quantitative analysis of product components by using a liquid chromatograph.

[0029] As preferred, in step (1), the feeding ratio of HBIW, DMF, PhBr, nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst and Ac2O is 15g:127mL:0.3mL:0.2g:20mL.

[0030] As preferred, in step (2), the feeding ratio of the solid containing TADBIW and catalyst, acetic acid, nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst and deionized water is 15g:127mL:0.2g:18mL, and the mass of the solid containing TADBIW and catalyst is based on the mass of HBIW required for its preparation.

[0031] Compared with the prior art, the beneficial effects of the present application are embodied in:

[0032] (1) The catalyst prepared in the present application has N and F dopants doped in the TiO2 lattice, which plays a synergistic promotion role, including larger surface area, higher anatase crystallinity and enhanced acid sites, which is beneficial to increase the catalytic activity.

[0033] (2) The prepared catalyst of the present application introduces transition metal zirconium, the addition of Zr can form small size, electron-rich palladium nanoparticles (Pd NPs), the formation of Pd NPs with good dispersion and small volume and the electronic effect between Pd and Zr together promote the enhancement of the hydrogenolysis activity of the two-component catalyst. At the same time, a dispersing agent is added during the preparation process, which enhances the interaction between palladium and zirconium, enables the reduced active component palladium to be uniformly dispersed on the surface, makes the intermetallic synergistic effect stronger, and improves the activity of the catalyst,

[0034] (3) The catalyst used in the present application is simple to prepare.

[0035] (4) The prepared catalyst of the present application is applied to the continuous hydrogenolysis debenzylization reaction of hexabenzylhexaazaisowurtzitane (HBIW), has high reaction activity, yield and stability, reduces the use amount of noble metal palladium, and can effectively reduce the production cost. (IV) DESCRIPTION OF DRAWINGS

[0036] Figure 1 The XRD pattern of the Pd7Zr2 / TiO2-3%N,F catalyst prepared for Example 2.

[0037] Figure 2 The H2-TPR pattern of the Pd7Zr2 / TiO2-3%N,F catalyst prepared for Example 2. (V) PREFERRED EMBODIMENT

[0038] The present application will be further described below through specific examples, but the protection scope of the present application is not limited to this.

[0039] The raw materials and reagents used in the present application are commercially available.

[0040] Example 1

[0041] Preparation method of nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst:

[0042] (1) First, 0.0163 g of ammonium fluoride is added to a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution is added to adjust the pH value of the solution to 4-5. Then, 5 mL of tetrabutyl titanate is added to the solution under continuous magnetic stirring, and the mixture is stirred for 2 h to form a transparent and uniform mixture, which is aged at room temperature for 12 h until a transparent gel is formed. Then, the obtained gel is placed in a vacuum drying oven at 80℃ for drying for 12 h, and then ground with a agate mortar to obtain a dry gel powder; finally, the dry gel powder is placed in a muffle furnace and calcined at 400℃ for 2 h, and then cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which is denoted as TiO2-3%N,F;

[0043] (2) Take 0.2666 g of palladium chloride and 0.0922 g of zirconium nitrate pentahydrate respectively, dissolve them in a proper amount of deionized water to prepare the precursor solutions of palladium and zirconium respectively;

[0044] (3) Take 1.8135 g of titanium dioxide carrier and 80 mL of deionized water, mix them to form a uniform slurry, then add the precursor solutions of palladium and zirconium obtained in step (1) and 0.2000 g of polyvinylpyrrolidone in sequence, stir to stabilize, heat to 70℃ and keep stirring for 4 h; slowly add 5% sodium hydroxide solution to the above suspension, adjust the pH value of the solution to be greater than 10.0, and continue stirring for 2 h; perform suction filtration on the above suspension, and wash with deionized water until the pH of the filtrate is neutral, then dry the obtained sample at 110℃ under vacuum for 12 h, and then reduce it at 150℃ under H2 atmosphere for 2 h, to obtain an 8% Pd-1% Zr / TiO2-3% N,F dual-component catalyst.

[0045] Application of the catalyst in the continuous hydrogenolysis debenzyl reaction of benzyl hexaazaisowurtzitane (HBIW):

[0046] (1) HBIW hydrogenolysis reaction: add 15.00 g of HBIW, 127 mL of DMF, 0.3 mL of PhBr, 0.2 g of catalyst, and 20 mL of Ac2O in sequence into a reaction kettle, first perform continuous hydrogenation reaction at 25℃, 0.5 MPa hydrogen pressure, and stirring for 8 h, then increase the temperature to 40℃ and continue the reaction for 16 h, filter the obtained reaction liquid to remove the filtrate, and place the filter cake in a blast oven to dry at 110℃ for 2 h, to obtain a gray-white solid containing the target product TADBIW and the catalyst, and calculate the TADBIW yield after the first step of HBIW hydrogenolysis reaction by weighing the mass;

[0047] (2) TADBIW hydrogenolysis reaction: weigh the filter cake dried after the first step of hydrogenolysis reaction, add it into a reaction kettle together with 127 mL of acetic acid, perform acid washing at 60℃ for 2 h to fully dissolve the solid product of the first step, then add 0.20 g of catalyst and 18 mL of deionized water in sequence, and then perform continuous hydrogenation reaction at 60℃, 1.5 MPa hydrogen pressure, and stirring for 24 h, then perform suction filtration, and wash with acetic acid, to obtain a black solid which is the catalyst, and the required product TAIW which is dissolved in the filtrate. Perform quantitative analysis of the product components of the second step of hydrogenation product by using a liquid chromatograph.

[0048] Example 2

[0049] Preparation method of nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst:

[0050] (1) First, 0.0163 g of ammonium fluoride was added to a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution was added to adjust the pH of the solution to 4-5. Then, 5 mL of tetrabutyl titanate was added to the solution under continuous magnetic stirring, and the solution was stirred for 2 h to form a transparent and uniform mixture, which was aged at room temperature for 12 h until a transparent gel was formed. After that, the obtained gel was placed in a vacuum drying oven at 80°C for 12 h, and then ground with a marble mortar to obtain a dry gel powder. Finally, the dry gel powder was placed in a muffle furnace and calcined at 400°C for 2 h, and then cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which was denoted as TiO2-3%N,F;

[0051] (2) 0.2666 g of palladium chloride and 0.1844 g of zirconium nitrate pentahydrate were weighed and dissolved in an appropriate amount of deionized water to prepare precursor solutions of palladium and zirconium, respectively;

[0052] (3) 1.7870 g of titanium dioxide carrier and 80 mL of deionized water were mixed and stirred to form a uniform slurry, and then the precursor solutions of palladium and zirconium obtained in step (1) were added in sequence, and 0.2000 g of polyvinylpyrrolidone was added and stirred to stabilize, and heated to 70°C and kept stirring for 4 h; 5% sodium hydroxide solution was slowly added dropwise to the above suspension, and the pH of the solution was adjusted to greater than 10.0, and stirring was continued for 2 h; the above suspension was filtered, and washed with deionized water until the filtrate was neutral, and the obtained sample was vacuum dried at 110°C for 12 h, and then reduced under H2 atmosphere at 150°C for 2 h to obtain a Pd7Zr2 / TiO2-3%N,F bicomponent catalyst.

[0053] The operation and parameters of the continuous hydrogenolysis debenzyl reaction of the benzyl hexaazaisowurtzitane (HBIW) in this example are the same as those in Example 1.

[0054] Example 3

[0055] Preparation method of palladium-zirconium bimetallic catalyst supported on nitrogen-fluorine co-doped titanium dioxide:

[0056] (1) First, 0.0163 g of ammonium fluoride was added to a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution was added to adjust the pH of the solution to 4-5. Then, 5 mL of tetrabutyl titanate was added to the solution under continuous magnetic stirring, and the solution was stirred for 2 h to form a transparent and uniform mixture, which was aged at room temperature for 12 h until a transparent gel was formed. After that, the obtained gel was placed in a vacuum drying oven at 80°C for 12 h, and then ground with a marble mortar to obtain a dry gel powder. Finally, the dry gel powder was placed in a muffle furnace and calcined at 400°C for 2 h, and then cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which was denoted as TiO2-3%N,F;

[0057] (2) Take 0.2666 g of palladium chloride and 0.2767 g of zirconium nitrate pentahydrate respectively to dissolve in appropriate amount of deionized water to prepare the precursor solution of palladium and zirconium respectively;

[0058] (3) Take 1.7606 g of titanium dioxide carrier and 80 mL of deionized water to mix, after stirring to form a uniform slurry, add the precursor solution of palladium and zirconium obtained in step (1) in turn, and add 0.2000 g of polyvinylpyrrolidone to stir and stabilize, heat to 70℃ and keep stirring for 4h; slowly add 5% sodium hydroxide solution to the above suspension, adjust the pH value of the solution to be greater than 10.0, continue to stir for 2h; the above suspension is filtered and washed with deionized water until the pH of the filtrate is neutral, the obtained sample is dried at 110℃ under vacuum for 12h, and then reduced at 150℃ under H2 atmosphere for 2h, to obtain a Pd7Zr3 / TiO2-3%N,F dual-component catalyst.

[0059] The operation and parameters of the continuous debenzylation reaction of benzylhexaazaisowurtzitane (HBIW) in this example 6 are the same as those in example 1.

[0060] Example 4

[0061] Preparation method of nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst:

[0062] (1) First, add 0.0163 g of ammonium fluoride to a mixture of 50 mL of ethanol and 5 mL of deionized water, and add appropriate amount of acetic acid solution to adjust the pH value of the solution to 4-5. Then, under continuous magnetic stirring, add 5 mL of tetrabutyl titanate to the solution, stir for 2h to form a transparent and uniform mixture, and age it at room temperature for 12h until a transparent gel is formed. Then, the obtained gel is placed in a vacuum drying oven at 80℃ for 12h, and then ground with a agate mortar to obtain a dry gel powder; finally, the dry gel powder is placed in a muffle furnace and calcined at 400℃ for 2h, and cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which is denoted as TiO2-3%N,F;

[0063] (1) Take 0.2666 g of palladium chloride and 0.2767 g of zirconium nitrate pentahydrate respectively to dissolve in appropriate amount of deionized water to prepare the precursor solution of palladium and zirconium respectively;

[0064] (2) Take 1.7341 g of titanium dioxide carrier and 80 mL of deionized water, mix and stir to form a uniform slurry, then add the palladium and zirconium precursor solutions obtained in step (1) in turn, while adding 0.2000 g of polyvinylpyrrolidone to stir and stabilize, heat to 70°C and keep stirring for 4 h; slowly add 5% sodium hydroxide solution to the above suspension, adjust the solution pH value to be greater than 10.0, continue to stir for 2 h; the above suspension is filtered and washed with deionized water until the filtrate is neutral, the obtained sample is vacuum dried at 110°C for 12 h, then reduced at 150°C under H2 atmosphere for 2 h, to obtain a Pd7Zr4 / 3%N,F dual-component catalyst.

[0065] The operation and parameters of the continuous hydrogenolysis debenzyl reaction of the benzyl hexaazaisowurtzitane (HBIW) in this example are the same as those in example 1.

[0066] Example 5

[0067] Preparation method of nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst:

[0068] (1) First, 0.0163 g of ammonium fluoride is added to a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution is added to adjust the pH value of the solution to 4-5. Then, 5 mL of tetrabutyl titanate is added to the solution under continuous magnetic stirring, and stirred for 2 h to form a transparent and uniform mixture, which is aged at room temperature for 12 h until a transparent gel is formed. Then, the obtained gel is placed in a vacuum drying oven and dried at 80°C for 12 h, and then ground with a agate mortar to obtain a dry gel powder; finally, the dry gel powder is placed in a muffle furnace and calcined at 400°C for 2 h, and cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which is denoted as TiO2-3%N,F;

[0069] (2) Take 0.2666 g of palladium chloride and 0.4612 g of zirconium nitrate pentahydrate and dissolve them in an appropriate amount of deionized water respectively to prepare palladium and zirconium precursor solutions;

[0070] (3) Take 1.7076 g of titanium dioxide carrier and 80 mL of deionized water, mix and stir to form a uniform slurry, then add the palladium and zirconium precursor solutions obtained in step (1) in turn, while adding 0.2000 g of polyvinylpyrrolidone to stir and stabilize, heat to 70°C and keep stirring for 4 h; slowly add 5% sodium hydroxide solution to the above suspension, adjust the solution pH value to be greater than 10.0, continue to stir for 2 h; the above suspension is filtered and washed with deionized water until the filtrate is neutral, the obtained sample is vacuum dried at 110°C for 12 h, then reduced at 150°C under H2 atmosphere for 2 h, to obtain a Pd7Zr5 / TiO2-3%N,F dual-component catalyst.

[0071] The operation and parameters of the continuous debenzylation reaction of hexabenzylhexaazaisowurtzitane (HBIW) in this example are the same as those in Example 1.

[0072] Example 6

[0073] A method for preparing a nitrogen-fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst comprises the following steps:

[0074] (1) First, 0.0054 g of ammonium fluoride is added to a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution is added to adjust the pH of the solution to 4-5. Then, 5 mL of tetrabutyl titanate is added to the solution under continuous magnetic stirring, and the solution is stirred for 2 h to form a transparent and uniform mixture, which is aged at room temperature for 12 h until a transparent gel is formed. After that, the obtained gel is placed in a vacuum drying oven at 80°C for 12 h, and then ground with a agate mortar to obtain a dry gel powder; finally, the dry gel powder is placed in a muffle furnace and calcined at 400°C for 2 h, and then cooled to room temperature to obtain a fluorine-nitrogen co-doped titanium dioxide carrier, which is denoted as TiO2-1%N,F;

[0075] (2) 0.2666 g of palladium chloride and 0.1844 g of zirconium nitrate pentahydrate are weighed and dissolved in an appropriate amount of deionized water to prepare a precursor solution of palladium and zirconium, respectively;

[0076] (3) 1.7870 g of titanium dioxide carrier and 80 mL of deionized water are mixed to form a uniform slurry, and then the precursor solutions of palladium and zirconium obtained in step (1) are added, followed by the addition of 0.2000 g of polyvinylpyrrolidone, and the mixture is stirred and heated to 70°C for 4 h; 5% sodium hydroxide solution is slowly added dropwise to the above suspension, and the pH of the solution is adjusted to greater than 10.0, and the stirring is continued for 2 h; the above suspension is filtered, and washed with deionized water until the pH of the filtrate is neutral; the obtained sample is vacuum dried at 110°C for 12 h, and then reduced under H2 atmosphere at 150°C for 2 h to obtain a Pd7Zr2 / TiO2-1%N,F bimetallic catalyst.

[0077] The operation and parameters of the continuous debenzylation reaction of hexabenzylhexaazaisowurtzitane (HBIW) in this example are the same as those in Example 1.

[0078] Example 7

[0079] A method for preparing a nitrogen-fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst comprises the following steps:

[0080] (1) First, 0.0109 g of ammonium fluoride was added into a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution was added to adjust the pH of the solution to 4-5. Then, 5 mL of tetrabutyl titanate was added into the solution under continuous magnetic stirring, and the solution was stirred for 2 h to form a transparent and uniform mixture, which was aged at room temperature for 12 h until a transparent gel was formed. After that, the obtained gel was placed in a vacuum drying oven and dried at 80 °C for 12 h, and then ground into dry gel powder with a marble mortar. Finally, the dry gel powder was calcined in a muffle furnace at 400 °C for 2 h, and cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which was denoted as TiO2-2%N,F;

[0081] (2) 0.2666 g of palladium chloride and 0.1844 g of zirconium nitrate pentahydrate were weighed and dissolved in an appropriate amount of deionized water to prepare a precursor solution of palladium and zirconium, respectively;

[0082] (3) 1.7870 g of titanium dioxide carrier and 80 mL of deionized water were mixed and stirred to form a uniform slurry, and then the precursor solutions of palladium and zirconium obtained in step (1) were added, and 0.2000 g of polyvinylpyrrolidone was added and stirred to stabilize, and heated to 70 °C and kept stirring for 4 h; 5% sodium hydroxide solution was slowly added dropwise into the above suspension, and the pH of the solution was adjusted to be greater than 10.0, and the stirring was continued for 2 h; the above suspension was filtered, and washed with deionized water until the pH of the filtrate was neutral. The obtained sample was dried at 110 °C for 12 h under vacuum, and then reduced at 150 °C under H2 atmosphere for 2 h to obtain a Pd7Zr2 / TiO2-2%N,F bicomponent catalyst.

[0083] The operation and parameters of the continuous hydrogenolysis debenzyl reaction of the benzyl hexaazaisowurtzitane (HBIW) in this example 6 are the same as those in example 1.

[0084] Example 8

[0085] A method for preparing a palladium-zirconium bimetallic catalyst supported on nitrogen and fluorine co-doped titanium dioxide:

[0086] (1) First, 0.0109 g of ammonium fluoride was added into a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution was added to adjust the pH of the solution to 4-5. Then, 5 mL of tetrabutyl titanate was added into the solution under continuous magnetic stirring, and the solution was stirred for 2 h to form a transparent and uniform mixture, which was aged at room temperature for 12 h until a transparent gel was formed. After that, the obtained gel was placed in a vacuum drying oven and dried at 80 °C for 12 h, and then ground into dry gel powder with a marble mortar. Finally, the dry gel powder was calcined in a muffle furnace at 400 °C for 2 h, and cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which was denoted as TiO2-2%N,F;

[0087] (2) Take 0.2666 g of palladium chloride and 0.1844 g of zirconium nitrate pentahydrate respectively to dissolve in appropriate amount of deionized water to prepare the precursor solution of palladium and zirconium respectively;

[0088] (3) Take 1.7870 g of titanium dioxide carrier and 80 mL of deionized water to mix, form a uniform slurry after stirring, then add the precursor solution of palladium and zirconium obtained in step (1) in turn, add 0.2000 g of polyvinylpyrrolidone while stirring to stabilize, heat to 70℃ and keep stirring for 4h; slowly add 5% sodium hydroxide solution to the above suspension, adjust the pH value of the solution to be greater than 10.0, continue to stir for 2h; the above suspension is filtered and washed with deionized water until the pH of the filtrate is neutral. The obtained sample is dried at 110℃ under vacuum for 12h, and then reduced under H2 atmosphere at 150℃ for 2h to obtain a Pd7Zr2 / TiO2-4%N,F two-component catalyst.

[0089] The operation and parameters of the continuous debenzylation reaction of benzylhexaazaisowurtzitane (HBIW) in this example 6 are the same as those in example 1.

[0090] Example 9

[0091] Preparation method of nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst:

[0092] (1) First, 0.0272 g of ammonium fluoride is added to a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution is added to adjust the pH value of the solution to 4-5. Then, 5 mL of tetrabutyl titanate is added to the solution under continuous magnetic stirring, and stirred for 2h to form a transparent and uniform mixture. The obtained mixture is aged at room temperature for 12h until a transparent gel is formed. Then, the obtained gel is placed in a vacuum drying oven and dried at 80℃ for 12h, and then ground with a agate mortar to obtain a dry gel powder. Finally, the dry gel powder is placed in a muffle furnace and calcined at 400℃ for 2h, and then cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which is denoted as TiO2-5%N,F;

[0093] (2) Take 0.2666 g of palladium chloride and 0.1844 g of zirconium nitrate pentahydrate respectively to dissolve in appropriate amount of deionized water to prepare the precursor solution of palladium and zirconium respectively;

[0094] (3) Take 1.7870 g of titanium dioxide carrier and 80 mL of deionized water, mix and stir to form a uniform slurry, then add the palladium and zirconium precursor solutions obtained in step (1) in turn, while adding 0.2000 g of polyvinylpyrrolidone to stabilize the stirring, and heat to 70°C for 4 h of stirring; slowly add 5% sodium hydroxide solution to the above suspension, adjust the solution pH to greater than 10.0, continue stirring for 2 h; the above suspension is filtered, and washed with deionized water until the filtrate is neutral, the obtained sample is vacuum dried at 110°C for 12 h, then reduced at 150°C under H2 atmosphere for 2 h, to obtain a Pd7Zr2 / TiO2-5%N,F two-component catalyst.

[0095] The operation and parameters of the continuous hydrogenolysis debenzyl reaction of the benzyl hexaazaisowurtzitane (HBIW) in this example are the same as those in example 1.

[0096] Example 10

[0097] Preparation method of nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst:

[0098] (1) First, 0.0163 g of ammonium fluoride is added to a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution is added to adjust the pH of the solution to 4-5. Then, 5 mL of tetrabutyl titanate is added to the solution under continuous magnetic stirring, and stirred for 2 h to form a transparent and uniform mixture, which is aged at room temperature for 12 h until a transparent gel is formed. Then, the obtained gel is placed in a vacuum drying oven and dried at 80°C for 12 h, and then ground with a agate mortar to obtain a dry gel powder; finally, the dry gel powder is placed in a muffle furnace and calcined at 400°C for 2 h, and cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which is denoted as TiO2-3%N,F;

[0099] (2) Take 0.2666 g of palladium chloride and 0.1844 g of zirconium nitrate pentahydrate, respectively, and dissolve them in an appropriate amount of deionized water to prepare palladium and zirconium precursor solutions;

[0100] (3) Take 1.7870 g of titanium dioxide carrier and 80 mL of deionized water, mix and stir to form a uniform slurry, then add the palladium and zirconium precursor solutions obtained in step (1) in turn, while adding 0.2000 g of polyvinylpyrrolidone to stabilize the stirring, and heat to 70°C for 4 h of stirring; slowly add 5% sodium hydroxide solution to the above suspension, adjust the solution pH to 10.0, continue stirring for 2 h; the above suspension is filtered, and washed with deionized water until the filtrate is neutral, the obtained sample is vacuum dried at 110°C for 12 h, then reduced at 150°C under H2 atmosphere for 2 h, to obtain a Pd7Zr2 / TiO2-5%N,F two-component catalyst.

[0101] The operation and parameters of the continuous debenzylation reaction of the hexabenzylhexaazaisowurtzitane (HBIW) in this example are the same as those in Example 1.

[0102] Example 11

[0103] A method for preparing a nitrogen-fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst:

[0104] (1) First, 0.0163 g of ammonium fluoride was added to a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution was added to adjust the pH of the solution to 4-5. Then, 5 mL of tetrabutyl titanate was added to the solution under continuous magnetic stirring, and the solution was stirred for 2 h to form a transparent and uniform mixture, which was aged at room temperature for 12 h until a transparent gel was formed. After that, the obtained gel was placed in a vacuum drying oven at 80°C for 12 h, and then ground with a agate mortar to obtain a dry gel powder; finally, the dry gel powder was placed in a muffle furnace and calcined at 400°C for 2 h, and then cooled to room temperature to obtain a fluorine-nitrogen co-doped titanium dioxide support, which was denoted as TiO2-3%N,F;

[0105] (2) 0.2666 g of palladium chloride and 0.1844 g of zirconium nitrate pentahydrate were weighed and dissolved in an appropriate amount of deionized water to prepare the precursor solutions of palladium and zirconium, respectively;

[0106] (3) 1.7870 g of titanium dioxide support and 80 mL of deionized water were mixed and stirred to form a uniform slurry, and then the precursor solutions of palladium and zirconium obtained in step (1) were added, followed by the addition of 0.2000 g of ethylenediamine, and the mixture was stirred and stabilized, and then heated to 70°C and kept stirring for 4 h; 5% sodium hydroxide solution was slowly added dropwise to the above suspension, and the pH of the solution was adjusted to 10.0, and the stirring was continued for 2 h; the above suspension was filtered, and washed with deionized water until the pH of the filtrate was neutral; the obtained sample was vacuum dried at 110°C for 12 h, and then reduced under H2 atmosphere at 150°C for 2 h to obtain the desired bimetallic catalyst.

[0107] The operation and parameters of the continuous debenzylation reaction of the hexabenzylhexaazaisowurtzitane (HBIW) in this example are the same as those in Example 1.

[0108] Example 12

[0109] A method for preparing a nitrogen-fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst:

[0110] (1) First, 0.0163 g of ammonium fluoride was added to a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution was added to adjust the pH of the solution to 4-5. Then, 5 mL of tetrabutyl titanate was added to the solution under continuous magnetic stirring, and the solution was stirred for 2 h to form a transparent and uniform mixture, which was aged at room temperature for 12 h until a transparent gel was formed. After that, the obtained gel was placed in a vacuum drying oven at 80°C for 12 h, and then ground with a marble mortar to obtain a dry gel powder; finally, the dry gel powder was placed in a muffle furnace and calcined at 200°C for 2 h, and then cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which was denoted as TiO2-3%N,F;

[0111] (2) 0.2666 g of palladium chloride and 0.1844 g of zirconium nitrate pentahydrate were weighed and dissolved in an appropriate amount of deionized water to prepare a precursor solution of palladium and zirconium, respectively;

[0112] (3) 1.7870 g of titanium dioxide carrier and 80 mL of deionized water were mixed and stirred to form a uniform slurry, and then the precursor solutions of palladium and zirconium obtained in step (1) were added, followed by the addition of 0.2000 g of polyvinylpyrrolidone for stirring and stabilization, and the temperature was raised to 70°C and maintained for 4 h. 5% sodium hydroxide solution was slowly added dropwise to the above suspension, and the pH of the solution was adjusted to greater than 10.0, and the stirring was continued for 2 h. The above suspension was filtered, and washed with deionized water until the pH of the filtrate was neutral. The obtained sample was vacuum dried at 110°C for 12 h, and then reduced under H2 atmosphere at 150°C for 2 h to obtain a Pd7Zr2 / TiO2-3%N,F bicomponent catalyst.

[0113] The operation and parameters of the continuous hydrogenolysis debenzyl reaction of the benzyl hexaazaisowurtzitane (HBIW) in this example 6 are the same as those in example 1.

[0114] Example 13

[0115] A method for preparing a palladium-zirconium bimetallic catalyst supported on nitrogen and fluorine co-doped titanium dioxide:

[0116] (1) First, 0.0163 g of ammonium fluoride was added to a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution was added to adjust the pH of the solution to 4-5. Then, 5 mL of tetrabutyl titanate was added to the solution under continuous magnetic stirring, and the solution was stirred for 2 h to form a transparent and uniform mixture, which was aged at room temperature for 12 h until a transparent gel was formed. After that, the obtained gel was placed in a vacuum drying oven at 80°C for 12 h, and then ground with a marble mortar to obtain a dry gel powder; finally, the dry gel powder was placed in a muffle furnace and calcined at 300°C for 2 h, and then cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which was denoted as TiO2-3%N,F;

[0117] (2) 0.2666 g of palladium chloride and 0.1844 g of zirconium nitrate pentahydrate were weighed and dissolved in deionized water respectively to prepare the precursor solutions of palladium and zirconium respectively;

[0118] (3) 1.7870 g of titanium dioxide carrier and 80 mL of deionized water were mixed to form a uniform slurry, and then the precursor solutions of palladium and zirconium obtained in step (1) were added, and 0.2000 g of polyvinylpyrrolidone was added while stirring to stabilize, and heated to 70°C and kept stirring for 4 h; 5% sodium hydroxide solution was slowly added dropwise into the above suspension, and the pH value of the solution was adjusted to be greater than 10.0, and the stirring was continued for 2 h; the above suspension was filtered, and washed with deionized water until the pH of the filtrate was neutral, and the obtained sample was dried at 110°C under vacuum for 12 h, and then reduced under H2 atmosphere at 150°C for 2 h, to obtain a Pd7Zr2 / TiO2-3%N,F two-component catalyst.

[0119] The operation and parameters of the continuous debenzylation reaction of benzylhexaazaisowurtzitane (HBIW) in this example six are the same as those in example 1.

[0120] Comparative example 1

[0121] Preparation method of nitrogen and fluorine co-doped titanium dioxide supported palladium catalyst:

[0122] (1) First, 0.0163 g of ammonium fluoride was added to a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution was added to adjust the pH of the solution to 4-5. Then, 5 mL of tetrabutyl titanate was added to the solution under continuous magnetic stirring, and stirred for 2 h to form a transparent and uniform mixture, which was aged at room temperature for 12 h until a transparent gel was formed. Then, the obtained gel was placed in a vacuum drying oven and dried at 80°C for 12 h, and then ground with a agate mortar to obtain a dry gel powder; finally, the dry gel powder was placed in a muffle furnace and calcined at 400°C for 2 h, and cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which was marked as TiO2-3%N,F;

[0123] (2) 0.2666 g of palladium chloride was weighed and dissolved in deionized water to prepare a precursor solution of palladium;

[0124] (3) Weigh 1.8400 g of titanium dioxide carrier and 80 mL of deionized water, mix and stir to form a uniform slurry, then add the palladium and zirconium precursor solution obtained in step (1) in turn, while adding 0.2000 g of polyvinylpyrrolidone to stir and stabilize, heat to 70°C and keep stirring for 4 h; slowly add 5% sodium hydroxide solution to the above suspension, adjust the solution pH to 10.0, continue stirring for 2 h; the above suspension is filtered, and washed with deionized water until the filtrate is neutral, the obtained sample is vacuum dried at 110°C for 12 h, then reduced at 150°C under H2 atmosphere for 2 h, to obtain the desired catalyst.

[0125] The operation and parameters of the continuous debenzylation reaction of hexabenzylhexaazaisowurtzitane (HBIW) in the present comparative example are the same as those of Example 1.

[0126] Table 1 Effect of the content of metal additive zirconium on the catalyst

[0127]

[0128] Comparative Example 2

[0129] Preparation method of titanium dioxide supported palladium catalyst:

[0130] (1) First, add an appropriate amount of acetic acid solution to the mixture of 50 mL of ethanol and 5 mL of deionized water to adjust the pH of the solution to 4-5. Then, under continuous magnetic stirring, add 5 mL of tetrabutyl titanate to the solution, stir for 2 h to form a transparent and uniform mixture, and age it at room temperature for 12 h until a transparent gel is formed. Then, the obtained gel is placed in a vacuum drying oven and dried at 80°C for 12 h, and then ground with a agate mortar to obtain a dry gel powder; finally, the dry gel powder is placed in a muffle furnace and calcined at 400°C for 2 h, and then cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which is denoted as TiO2;

[0131] (2) Weigh 0.2666 g of palladium chloride and dissolve it in an appropriate amount of deionized water to prepare a palladium precursor solution;

[0132] (3) Weigh 1.8400 g of titanium dioxide carrier and 80 mL of deionized water, mix and stir to form a uniform slurry, then add the palladium and zirconium precursor solution obtained in step (1) in turn, while adding 0.2000 g of polyvinylpyrrolidone to stir and stabilize, heat to 70°C and keep stirring for 4 h; slowly add 5% sodium hydroxide solution to the above suspension, adjust the solution pH to 10.0, continue stirring for 2 h; the above suspension is filtered, and washed with deionized water until the filtrate is neutral, the obtained sample is vacuum dried at 110°C for 12 h, then reduced at 150°C under H2 atmosphere for 2 h, to obtain the desired catalyst.

[0133] The operation and parameters of the continuous debenzylation reaction of hexabenzylhexaazaiswuzzanane (HBIW) are the same as those of Example 1.

[0134] Table 2 Influence of nitrogen and fluorine doping amount on catalyst

[0135]

[0136]

[0137] Comparative Example 3

[0138] A method for preparing a nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst comprises the following steps:

[0139] (1) First, 0.0163 g of ammonium fluoride is added to a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution is added to adjust the pH of the solution to 4-5. Then, 5 mL of tetrabutyl titanate is added to the solution under continuous magnetic stirring, and the solution is stirred for 2 h to form a transparent and uniform mixture, which is aged at room temperature for 12 h until a transparent gel is formed. After that, the obtained gel is placed in a vacuum drying oven at 80°C for 12 h, and then ground with a agate mortar to obtain a dry gel powder; finally, the dry gel powder is placed in a muffle furnace and calcined at 400°C for 2 h, and then cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which is denoted as TiO2-3%N,F;

[0140] (2) 0.2666 g of palladium chloride and 0.1844 g of zirconium nitrate pentahydrate are weighed and dissolved in an appropriate amount of deionized water to prepare a precursor solution of palladium and zirconium, respectively;

[0141] (3) 1.7870 g of titanium dioxide carrier and 80 mL of deionized water are mixed and stirred to form a uniform slurry, and then the precursor solutions of palladium and zirconium obtained in step (1) are added in sequence, and the temperature is heated to 70°C and kept stirring for 4 h; 5% sodium hydroxide solution is slowly added dropwise to the above suspension, and the pH of the solution is adjusted to 10.0, and the stirring is continued for 2 h; the above suspension is filtered, and washed with deionized water until the pH of the filtrate is neutral; the obtained sample is vacuum dried at 110°C for 12 h, and then reduced under H2 atmosphere at 150°C for 2 h to obtain the desired catalyst.

[0142] The operation and parameters of the continuous debenzylation reaction of hexabenzylhexaazaiswuzzanane (HBIW) are the same as those of Example 1.

[0143] Table 3 Influence of dispersant type on catalyst

[0144]

[0145] Comparative Example 4

[0146] Method for preparing nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst

[0147] (1) First, 0.0163 g of ammonium fluoride was added to a mixture of 50 mL of ethanol and 5 mL of deionized water, and an appropriate amount of acetic acid solution was added to adjust the pH of the solution to 4-5. Then, 5 mL of tetrabutyl titanate was added to the solution under continuous magnetic stirring, and the solution was stirred for 2 h to form a transparent and uniform mixture, which was aged at room temperature for 12 h until a transparent gel was formed. After that, the obtained gel was placed in a vacuum drying oven at 80°C for 12 h, and then ground with a agate mortar to obtain a dry gel powder; finally, the dry gel powder was placed in a muffle furnace and calcined at 500°C for 2 h, and then cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier, which was denoted as TiO2-3%N,F;

[0148] (2) 0.2666 g of palladium chloride and 0.1844 g of zirconium nitrate pentahydrate were weighed and dissolved in an appropriate amount of deionized water to prepare the precursor solutions of palladium and zirconium, respectively;

[0149] (3) 1.7870 g of titanium dioxide carrier and 80 mL of deionized water were mixed and stirred to form a uniform slurry, and then the precursor solutions of palladium and zirconium obtained in step (1) were added in sequence, and 0.2000 g of polyvinylpyrrolidone was added and stirred to stabilize, and heated to 70°C and kept stirring for 4 h; 5% sodium hydroxide solution was slowly added dropwise to the above suspension, and the pH of the solution was adjusted to greater than 10.0, and the stirring was continued for 2 h; the above suspension was filtered, and washed with deionized water until the pH of the filtrate was neutral, and the obtained sample was vacuum dried at 110°C for 12 h, and then reduced under H2 atmosphere at 150°C for 2 h to obtain a Pd7Zr2 / TiO2-3%N,F bimetallic catalyst.

[0150] The operation and parameters of the continuous hydrogenolysis debenzylization reaction of benzylhexaazaisowurtzitane (HBIW) in this example 6 are the same as those in example 1.

[0151] Table 4 Effect of different calcination temperatures of fluorine and nitrogen co-doped titanium dioxide carrier on the catalyst

[0152]

[0153] Comparative example 5

[0154] The preparation of the catalyst and the reaction conditions in this comparative example are the same as those in example 2. The used catalyst was recycled and applied to the second round of reaction, and the addition amount of the catalyst for the second round of reaction and subsequent reactions was reduced. In the first step of HBIW hydrogenolysis reaction, the amount of HBIW was reduced to 0.15 g, and in the second step of TADBIW hydrogenolysis reaction, the amount of TADBIW was reduced to 0.02 g.

[0155] Application of the catalyst in the continuous hydrogenolysis debenzylization reaction of benzylhexaazaisowurtzitane (HBIW):

[0156] (1) HBIW hydrogenolysis reaction: 15.00 g HBIW, 127 mL DMF, 0.3 mL PhBr, 0.2 g catalyst, 20 mL Ac2O were sequentially added into the reactor, and then continuous hydrogenation reaction was carried out at 25 °C, 0.5 MPa hydrogen pressure and stirring for 8 h, and then the temperature was increased to 40 °C for continuous reaction for 16 h. The obtained reaction liquid was filtered to remove the filtrate, and the filter cake was placed in a blast oven for drying at 110 °C for 2 h to obtain an off-white solid containing the target product TADBIW and the catalyst. After weighing, the TADBIW yield after the first step of HBIW hydrogenolysis reaction was calculated;

[0157] (2) TADBIW hydrogenolysis reaction: the filter cake dried by the first step of hydrogenolysis reaction was weighed and then added into the reactor together with 127 mL acetic acid. After acid washing at 60 °C for 2 h, 0.20 g of catalyst and 18 mL of deionized water were sequentially added, and then continuous hydrogenation reaction was carried out at 60 °C, 1.5 MPa hydrogen pressure and stirring for 24 h. After that, filtration was carried out, and the black solid obtained was washed with acetic acid. The required product TAIW was dissolved in the filtrate. The second step of hydrogenation product was subjected to quantitative analysis of product components by using a gas chromatograph.

[0158] Table 5 Stability evaluation of the catalyst

[0159]

[0160]

Claims

1. A method for preparing a nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst, characterized by: The preparation method is as follows: (1) First, add an appropriate amount of ammonium fluoride as a source of nitrogen and fluorine in a mixed solvent of ethanol and deionized water, and add an appropriate amount of an acidic solution to adjust the pH of the solution to 4-5 to shorten the gelation time and generate a transparent solution. Under continuous magnetic stirring, an appropriate amount of titanium-containing organic matter is added to the solution, stirred for 2-4 h to form a transparent and uniform mixture, which is aged at room temperature for 12-24 h until a transparent gel is formed. Then, the obtained gel is placed in a vacuum drying oven at 60-90 ℃ for 8-12 h, and then ground with a jade mortar to obtain a dry gel powder. Finally, the dry gel powder is placed in a muffle furnace and calcined at 200-500 ℃ for 2-4 h, and then cooled to room temperature to obtain a fluorine and nitrogen co-doped titanium dioxide carrier. This carrier is denoted as TiO2-x%N,F, wherein x%=n 氟化铵 / n Ti x100%=2-4%, wherein n Ti represents the number of moles of Ti contained in the titanium-containing organic matter; (2) a certain amount of the palladium-containing compound and the zirconium-containing compound are respectively dissolved in a proper amount of deionized water to prepare a precursor solution of palladium and zirconium respectively; (3) A certain amount of the fluorine-nitrogen co-doped titanium dioxide carrier prepared in step (1) and deionized water are mixed, and after stirring to form a uniform slurry, the precursor solution of palladium and zirconium obtained in step (2) is added, and a dispersing agent is added to stabilize the stirring, and heated to 60-80 ℃, and kept stirring for 4-6 h to obtain a suspension; slowly add an aqueous solution of an alkaline substance to the above suspension to adjust the pH value to greater than 10.0, and continue stirring for 1-2 h; the above suspension is filtered, and washed with deionized water until the filtrate is neutral, and the obtained sample is vacuum dried, and then reduced under H2 atmosphere to obtain a nitrogen-fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst; the dispersing agent is at least one of polyethylene glycol, polyvinylpyrrolidone, and ethylenediamine, and the amount of the dispersing agent is 5-20% of the mass of the catalyst, and the mass of the catalyst = m Pd +m ZrO2 +m 氮氟改性二氧化钛载体 ; The theoretical loading of Pd in the nitrogen-fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst is 5-10%, and the theoretical loading of Pd = m Pd / (m Pd +m ZrO2 +m 氮氟改性二氧化钛载体 ) × 100%, the molar ratio of palladium and zirconium is 7: (1-3), wherein m Pd represents the mass of palladium contained in the precursor solution of palladium, m ZrO2 represents the mass of ZrO2 converted from the mass of Zr contained in the precursor solution of zirconium.

2. The production method according to claim 1, characterized by: In step (1), the titanium-containing organic compound is at least one of tetraethyl titanate, tetraisopropyl titanate and tetrabutyl titanate.

3. The production method according to claim 1 or 2, characterized by: In step (1), the volume ratio of the titanium-containing organic compound, ethanol and water is 2-10:50:2-10.

4. The production method according to claim 1, wherein: In step (1), the acid solution is a 5-10wt% acetic acid or hydrochloric acid solution; in step (3), the aqueous solution of the basic substance is a 5-10wt% ammonia or NaOH solution.

5. The production method according to claim 1, wherein: In step (1), the calcination temperature is 300-400 ℃.

6. The production method according to claim 5, characterized by: In step (1), the calcination temperature is 400 ℃.

7. The production method according to claim 1, wherein: In step (2), the palladium compound is at least one of palladium chloride, sodium tetrachloropalladate, palladium acetate and palladium nitrate, and the zirconium compound is at least one of zirconium chloride, zirconium nitrate, zirconium oxychloride, zirconium acetate and zirconium n-propylate.

8. The production method according to claim 1, wherein: In step (3), the reduction condition is reduction under a hydrogen atmosphere at 100-400 ℃ for 1-4 h.

9. A nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst prepared by the preparation method according to any one of claims 1-8.

10. Application of the nitrogen and fluorine co-doped titanium dioxide supported palladium-zirconium bimetallic catalyst according to claim 9 in the synthesis of TAIW by continuous hydrogenolysis debenzylization of hexabenzylhexaazaisowurtzitane.

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