Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocynate waste residue, and preparation method and application thereof

Abstract

The invention relates to the technical field of ammonia treatment catalysts, in particular to a Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residues and a preparation method and application of the Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residues. S2, preparing a modified Ru precursor solution; s3, a carrier with the mass accounting for 0.1-20% of the mass of the modified Ru precursor solution is added into the modified Ru precursor solution, uniform dispersion and reaction are conducted, and turbid liquid is obtained; s4, heating the turbid liquid, and drying for 1-48 hours under the condition of 25-100 DEG C to obtain a solid product; and S5, calcining the solid product in a gas atmosphere to obtain the Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on the toluene diisocyanate waste residues. According to the preparation method, industrial waste residues are adopted as raw materials, solid waste emission is reduced, meanwhile, the preparation cost of the catalyst is remarkably reduced, and important economic and social benefits are achieved; the method is simple and easy to operate, low in energy consumption in the preparation process and suitable for large-scale production.

Description

Technical Field

[0001] The invention relates to the technical field of ammonia treatment catalysts, in particular to a Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue, a preparation method and an application thereof. Background Art

[0002] In the process of promoting the transformation of the national energy structure and the dual carbon goals, the development of clean and efficient new energy technologies has become a consensus. Hydrogen energy, as a zero-carbon clean fuel, has the advantages of only water as a combustion product, high energy density, and fast combustion speed. It is regarded as an important part of the future energy system, but the large-scale application of hydrogen energy faces severe challenges such as difficult hydrogen storage and transportation and poor safety. Ammonia, as a basic chemical raw material related to the national economy and people's livelihood, has shown broad development space in the field of green energy carriers and fuels due to its high hydrogen content, easy liquefaction storage, and mature and diverse storage and transportation methods. Based on this, the ammonia-hydrogen fusion new energy technology consisting of "clean energy driven hydrogen production-green hydrogen synthesis ammonia-long-term large-scale storage of liquid ammonia-large-scale cross-regional transportation of liquid ammonia-ammonia on-site decomposition to produce hydrogen" is considered to be one of the effective ways to break through the bottleneck of large-scale application of hydrogen energy. Among them, the synthesis and decomposition of ammonia has become the most important link in the development of the current ammonia-hydrogen fusion new energy technology, and the catalyst is undoubtedly the key to determining the efficiency of ammonia synthesis and decomposition.

[0003] The reason why Ru-based catalysts are recognized as the most effective catalysts in ammonia synthesis and decomposition to produce hydrogen is that there is a strong binding energy between the Ru element and the N element, which makes the Ru-based catalyst exhibit excellent bifunctional catalytic properties. At present, Ru-based catalysts mainly include supported catalytic materials such as metal oxides, molecular sieves, nitrides, and carbon materials. Among them, carbon materials (especially activated carbon) are widely used in the synthesis of Ru-based catalysts due to their high specific surface area and good electrical conductivity. However, it still faces problems such as high reaction temperature, easy agglomeration and sintering of active sites, and easy methanogenic deactivation of the carrier.

[0004] Toluene diisocyanate is an important chemical raw material, widely used in the production of polyurethane materials. With the rapid development of the polyurethane industry, the output of toluene diisocyanate has increased year by year. However, in its production process, a large amount of waste residue will inevitably be produced, which is now mainly treated by landfilling, incineration and other methods, which not only occupies a large amount of land resources, but also easily pollutes the environment. Toluene diisocyanate waste residue is a relatively common residue in the industry, with transparent components, and its main components include: toluene diisocyanate, toluenediamine, polyurea, tar. The inventor found in previous work that by hydrolyzing and pyrolyzing industrial toluene diisocyanate, a nitrogen-containing porous carbon material with a large specific surface area can be converted. If the nitrogen-containing porous carbon material obtained by converting industrial toluene diisocyanate is used to replace traditional activated carbon as a Ru-based catalyst carrier, it will not only achieve high-value utilization of solid waste materials, but also through the special electronic effects and active sites brought about by the introduction of nitrogen atoms, iron atoms, etc., it is expected to achieve a significant improvement in catalytic activity and stability in ammonia decomposition to produce hydrogen and ammonia synthesis. Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to address the problems of high reaction temperature, easy agglomeration and sintering of active sites, and easy methanogenic deactivation of carriers in the existing Ru-based ammonia synthesis and decomposition hydrogen production bifunctional catalysts, and provide a preparation method and application of Ru-loaded nitrogen-containing porous carbon bifunctional catalysts based on toluene diisocyanate waste residue.

[0006] To achieve the above object, the present invention provides the following technical solutions: The preparation method of Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue comprises the following steps: S1. Preparation of nitrogen-containing porous carbon material: toluene diisocyanate waste residue, 1,3-butanediol and ammonium bicarbonate are mixed in a mass ratio of 2:4:1, treated at 100-180°C for 2-5h to remove 1,3-butanediol, pyrolyzed in a nitrogen atmosphere at 600-800°C for 1-3h and a boric acid solution with a mass concentration of 10% is added during the pyrolysis process to obtain a nitrogen-containing porous carbon material; S2. Preparation of modified Ru precursor solution: The Ru precursor and the modified solution were mixed in a mass ratio of 1:10-13, and ultrasonically treated for 30-50 min to obtain a modified Ru precursor solution; S3. Adding 0.1-20% of the nitrogen-containing porous carbon material to the modified Ru precursor solution, uniformly dispersing and reacting, to obtain a suspension; S4. After heating the suspension, drying it at 25-100 ° C for 1-48h to obtain a solid product; S5. The solid product was calcined under a nitrogen atmosphere to obtain a Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue; Wherein, the preparation of the modified liquid comprises the following steps: S201. The tetrahydrofuran and the 10% aqueous solution of iron carbonate suspension were mixed and stirred in a mass ratio of 5-8:1 to obtain a primary mixed solution at a stirring speed of 450-550 r / min; S202. Add glacial acetic acid in an amount of 6-10% of the mass of the preliminary mixed solution to the primary mixed solution, stir at a speed of 450-550 r / min for 15-20 min at 20-23°C to obtain a modified solution.

[0007] Preferably, in step S1, the mass ratio of toluene diisocyanate waste residue to the boric acid solution with a mass concentration of 10% is 8-10:1.

[0008] Preferably, the specific surface area of ​​the nitrogen-containing porous carbon material obtained in step S1 is 100-1500 m 2 / g, nitrogen content is 5-20%.

[0009] Preferably, in step S2, the Ru precursor is one or more of ruthenium trichloride trihydrate, triruthenium dodecacarbonyl, ruthenium nitrosyl nitrate, ruthenium acetylacetonate, potassium ruthenate, and ruthenium acetate.

[0010] Preferably, the reaction temperature in step S3 is controlled at 0-60° C., and the reaction time is 1-24 h.

[0011] Preferably, in step S4, the heating temperature is 50-80° C. and the heating time is 1-6 h.

[0012] Preferably, in step S5, the calcination conditions are: heating to 300-700° C. at a rate of 5-20° C. / min and maintaining for 1-12 h.

[0013] Preferably, in the Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue obtained in step S5, the Ru loading amount is 0.1-15%.

[0014] A Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue is prepared according to the above preparation method.

[0015] The invention discloses an application of a Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue prepared by the preparation method described in the claims in hydrogen production by decomposition of ammonia and ammonia synthesis.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The modified liquid chemically bonds with the active groups on the surface of the nitrogen-containing porous carbon carrier to achieve a more solid load, which improves the dispersion and stability of the Ru active sites. At the same time, the introduction of iron ions in the catalytic process realizes the synergistic catalysis of multiple active sites, and the introduction of boron atoms in the high-value recycling technology process changes the surface acidity of the material, which is beneficial to the adsorption and activation of the reactants and improves the catalytic performance of the catalyst for ammonia synthesis and decomposition reactions.

[0017] 2. The preparation method of the present invention uses industrial waste residue as the carrier raw material, which not only reduces solid waste emissions, but also significantly reduces the preparation cost of the catalyst, and has important economic and social benefits. In addition, the preparation method is simple and easy to operate, and the preparation process has low energy consumption, and is suitable for large-scale production.

[0018] 3. The Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue prepared by the present invention can be simultaneously applied to ammonia synthesis and ammonia decomposition to produce hydrogen; compared with the Ru-based catalyst supported on activated carbon material, at the same reaction temperature, the ammonia generation rate and / or ammonia conversion efficiency are higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention is a process flow chart for preparing a Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue; Figure 2 N is the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue in Examples 1-3 of the present invention. 2 Adsorption-desorption isotherms; Figure 3 HAADF-STEM and corresponding element distribution diagram of the Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue in Example 1 of the present invention (Figure a is a STEM image of the Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue of the present invention; Figure b is the distribution of the C element in the obtained catalyst; Figure c is the distribution of the N element in the obtained catalyst; Figure d is the distribution of the Ru element in the obtained catalyst); Figure 4 This is a bar graph of the performance of the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue in Example 1 of the present invention for thermal catalytic ammonia decomposition and hydrogen production at different reaction temperatures; Figure 5 This is a bar graph showing the photothermal catalytic ammonia decomposition and hydrogen production performance of the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue at different reaction temperatures in Example 1 of the present invention; Figure 6This is a bar chart showing the photothermal catalytic ammonia decomposition and hydrogen production performance of the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue and the commercial Ru / C catalyst in Examples 1-8 of the present invention; Figure 7 This is a bar chart showing the photothermal catalytic ammonia synthesis performance of the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue at different reaction temperatures in Example 1 of the present invention; Figure 8 This is a bar chart showing the photothermal catalytic ammonia synthesis performance of the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue in Example 1 of the present invention and the commercial Ru / C catalyst. DETAILED DESCRIPTION

[0020] The present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] See also Figure 1-8 , the present invention provides a technical solution: Example 1 Preparation method of Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue: S1. Preparation of nitrogen-containing porous carbon material: Toluene diisocyanate waste residue, 1,3-butanediol and ammonium bicarbonate were mixed in a mass ratio of 2:4:1, treated at 100°C for 2h to remove 1,3-butanediol, and then pyrolyzed in a nitrogen atmosphere at 600°C for 1h. During the pyrolysis process, a 10% boric acid solution was added to obtain a 0.56wt% nitrogen-containing porous carbon material with a specific surface area of ​​826m 2 / g, the nitrogen content is 10%, wherein the mass ratio of toluene diisocyanate waste residue to boric acid solution is 9:1; S2. Preparation of modified Ru precursor solution: S201. The tetrahydrofuran and the 10% aqueous solution of iron carbonate suspension were mixed and stirred in a mass ratio of 6:1 to obtain a primary mixed solution; S202. Add glacial acetic acid in an amount of 7% of the initial mixed solution to the primary mixed solution, stir at 21° C. for 18 min to obtain a modified solution; S203. The mass concentration of 0.12% ruthenium acetylacetonate and the modified solution were mixed in a mass ratio of 1:12, and ultrasonically treated for 30 minutes to obtain a modified Ru precursor solution; S3. 8.5 g of nitrogen-containing porous carbon material was added to 100 g of modified Ru precursor solution, uniformly dispersed and reacted at 39 ° C for 14 h to obtain a suspension; S4. The suspension was heated at 65°C for 3h, and then dried at 50°C for 12h to obtain a solid product; S5. The solid product was calcined in a nitrogen atmosphere (the calcination conditions were: heating to 450°C at a rate of 13°C / min and maintaining for 3 hours) to obtain a Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue, wherein the Ru loading amount was 5%.

[0022] Example 2 Preparation method of Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue: S1. Preparation of nitrogen-containing porous carbon material: Toluene diisocyanate waste residue, 1,3-butanediol and ammonium bicarbonate were mixed in a mass ratio of 2:4:1, treated at 180°C for 5 h to remove 1,3-butanediol, and then pyrolyzed in a nitrogen atmosphere at 600°C for 1 h. During the pyrolysis process, a 10% boric acid solution was added to obtain a 0.56 wt% nitrogen-containing porous carbon material with a specific surface area of ​​603 m 2 / g, nitrogen content is 9%, wherein the mass ratio of toluene diisocyanate waste residue to boric acid solution is 8.9:1; S2. Preparation of modified Ru precursor solution: S201. The tetrahydrofuran and the 10% aqueous solution of iron carbonate suspension were mixed and stirred in a mass ratio of 6.5:1 to obtain a primary mixed solution; S202. Add glacial acetic acid in an amount of 7.6% of the initial mixed solution to the primary mixed solution, and stir at 21° C. for 17 min to obtain a modified solution; S203. The mass concentration of 0.12% ruthenium acetylacetonate and the modified solution were mixed in a mass ratio of 1:12.1, and ultrasonically treated for 35 minutes to obtain a modified Ru precursor solution; S3. 8.6 g of nitrogen-containing porous carbon material was added to 100 g of modified Ru precursor solution, uniformly dispersed and reacted at 33 ° C for 11 h to obtain a suspension; S4. The suspension was heated at 63°C for 2 h, and then dried at 37°C for 17 h to obtain a solid product; S5. The solid product was calcined in a nitrogen atmosphere (the calcination conditions were: heating to 500°C at a rate of 15°C / min and maintaining for 6 hours) to obtain a Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue, wherein the Ru loading amount was 5%.

[0023] Example 3 Preparation method of Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue: S1. Preparation of nitrogen-containing porous carbon material: Toluene diisocyanate waste residue, 1,3-butanediol and ammonium bicarbonate were mixed in a mass ratio of 2:4:1, treated at 110°C for 3 h to remove 1,3-butanediol, and then pyrolyzed in a nitrogen atmosphere at 670°C for 2.5 h. During the pyrolysis process, a 10% boric acid solution was added to obtain a 0.56 wt% nitrogen-containing porous carbon material with a specific surface area of ​​438 m 2 / g, the nitrogen content is 8%, wherein the mass ratio of toluene diisocyanate waste residue to boric acid solution is 8.6:1; S2. Preparation of modified Ru precursor solution: S201. The tetrahydrofuran and the 10% aqueous solution of iron carbonate suspension were mixed and stirred in a mass ratio of 6.8:1 to obtain a primary mixed solution; S202. Add 8.6% of the mass of glacial acetic acid to the primary mixed solution, stir at 22° C. for 18 min to obtain a modified solution; S203. The mass concentration of 0.12% ruthenium acetylacetonate and the modified solution were mixed in a mass ratio of 1:11.6, and ultrasonically treated for 40 minutes to obtain a modified Ru precursor solution; S3. 12.3 g of nitrogen-containing porous carbon material was added to 100 g of modified Ru precursor solution, uniformly dispersed and reacted at 42 ° C for 9 h to obtain a suspension; S4. The suspension was heated at 68°C for 2.5h, and then dried at 59°C for 12h to obtain a solid product; S5. The solid product was calcined in a nitrogen atmosphere (the calcination conditions were: heating to 480°C at a rate of 13°C / min and maintaining for 6 hours) to obtain a Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue, wherein the Ru loading amount was 5%.

[0024] Example 4 Preparation method of Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue: S1. Preparation of nitrogen-containing porous carbon material: Toluene diisocyanate waste residue, 1,3-butanediol and ammonium bicarbonate were mixed in a mass ratio of 2:4:1, treated at 130°C for 3 h to remove 1,3-butanediol, and then pyrolyzed in a nitrogen atmosphere at 800°C for 3 h. During the pyrolysis process, a 10% boric acid solution was added to obtain a 0.63 wt% nitrogen-containing porous carbon material with a specific surface area of ​​1500 m 2 / g, the nitrogen content is 20%, wherein the mass ratio of toluene diisocyanate waste residue to boric acid solution is 10:1; S2. Preparation of modified Ru precursor solution: S201. The tetrahydrofuran and the 10% aqueous solution of iron carbonate suspension were mixed and stirred in a mass ratio of 8:1 to obtain a primary mixed solution; S202. Add glacial acetic acid in an amount of 10% of the mass of the preliminary mixed solution to the primary mixed solution, stir at 23° C. for 20 min to obtain a modified solution; S203. The mass concentration of 0.09% ruthenium trichloride trihydrate and the modified solution were mixed in a mass ratio of 1:13, and ultrasonically treated for 50 minutes to obtain a modified Ru precursor solution; S3. Add 20 g of nitrogen-containing porous carbon material to 100 g of modified Ru precursor solution, disperse evenly and react at 60 ° C for 24 h to obtain a suspension; S4. The suspension was heated at 80°C for 6h, and then dried at 100°C for 48h to obtain a solid product; S5. The solid product was calcined in a nitrogen atmosphere (the calcination conditions were: heating to 700°C at a rate of 20°C / min and maintaining for 12 hours) to obtain a Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue, wherein the Ru loading amount was 15%.

[0025] Example 5 Preparation method of Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue: S1. Preparation of nitrogen-containing porous carbon material: Toluene diisocyanate waste residue, 1,3-butanediol and ammonium bicarbonate were mixed in a mass ratio of 2:4:1, treated at 150°C for 4 hours to remove 1,3-butanediol, and then pyrolyzed in a nitrogen atmosphere at 700°C for 2.5 hours. During the pyrolysis process, a 10% boric acid solution was added to obtain a 0.56 wt% nitrogen-containing porous carbon material with a specific surface area of ​​912 m 2 / g, the nitrogen content is 12%, wherein the mass ratio of toluene diisocyanate waste residue to boric acid solution is 9:1; S2. Preparation of modified Ru precursor solution: S201. The tetrahydrofuran and the 10% aqueous solution of iron carbonate suspension were mixed and stirred in a mass ratio of 7:1 to obtain a primary mixed solution; S202. Add 8% of the mass of glacial acetic acid to the primary mixed solution, stir at 22° C. for 18 min to obtain a modified solution; S203. The mass concentration of 0.24% ruthenium acetylacetonate was mixed with the modified solution in a mass ratio of 1:12.1, and ultrasonically treated for 40 minutes to obtain a modified Ru precursor solution; S3. 12 g of nitrogen-containing porous carbon material was added to 100 g of modified Ru precursor solution, uniformly dispersed and reacted at 40 ° C for 16 h to obtain a suspension; S4. The suspension was heated at 65°C for 4h, and then dried at 75°C for 35h to obtain a solid product; S5. The solid product was calcined in a nitrogen atmosphere (the calcination conditions were: heating to 600°C at a rate of 14°C / min and maintaining for 9 hours) to obtain a Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue, wherein the Ru loading amount was 9%.

[0026] Example 6 Preparation method of Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue: S1. Preparation of nitrogen-containing porous carbon material: Toluene diisocyanate waste residue, 1,3-butanediol and ammonium bicarbonate were mixed in a mass ratio of 2:4:1, treated at 140°C for 4 hours to remove 1,3-butanediol, and then pyrolyzed in a nitrogen atmosphere at 650°C for 2 hours. During the pyrolysis process, a 10% boric acid solution was added to obtain a 0.56 wt% nitrogen-containing porous carbon material with a specific surface area of ​​239 m 2 / g, the nitrogen content is 6%, wherein the mass ratio of toluene diisocyanate waste residue to boric acid solution is 8.3:1; S2. Preparation of modified Ru precursor solution: S201. The tetrahydrofuran and the 10% aqueous solution of iron carbonate suspension were mixed and stirred in a mass ratio of 5.5:1 to obtain a primary mixed solution; S202. Add glacial acetic acid in an amount of 7% of the initial mixed solution to the primary mixed solution, stir at 21° C. for 16 min to obtain a modified solution; S203. The mass concentration of 0.024% ruthenium acetylacetonate and the modified solution were mixed in a mass ratio of 1:11, and ultrasonically treated for 35 minutes to obtain a modified Ru precursor solution; S3. 3 g of nitrogen-containing porous carbon material was added to 100 g of modified Ru precursor solution, uniformly dispersed and reacted at 10 ° C for 5 h to obtain a suspension; S4. The suspension was heated at 55°C for 2h, and then dried at 40°C for 10h to obtain a solid product; S5. The solid product is calcined in a nitrogen atmosphere (the calcination conditions are: heating to 400°C at a rate of 8°C / min and maintaining for 3h) to obtain a Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue, wherein the Ru loading amount is 4%.

[0027] Example 7 Preparation method of Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue: S1. Preparation of nitrogen-containing porous carbon material: Toluene diisocyanate waste residue, 1,3-butanediol and ammonium bicarbonate were mixed in a mass ratio of 2:4:1, treated at 120°C for 4 h to remove 1,3-butanediol, and then pyrolyzed in a nitrogen atmosphere at 600°C for 1 h. During the pyrolysis process, a 10% boric acid solution was added to obtain a 0.38 wt% nitrogen-containing porous carbon material with a specific surface area of ​​100 m 2 / g, the nitrogen content is 5%, wherein the mass ratio of toluene diisocyanate waste residue to boric acid solution is 8:1; S2. Preparation of modified Ru precursor solution: S201. The tetrahydrofuran and the 10% aqueous solution of iron carbonate suspension were mixed and stirred in a mass ratio of 5:1 to obtain a primary mixed solution; S202. Add glacial acetic acid in an amount of 6% of the initial mixed solution to the primary mixed solution, stir at 20° C. for 15 min to obtain a modified solution; S203. The dodecacarbonyl triruthenium having a mass concentration of 0.043% and the modified solution were mixed in a mass ratio of 1:10, and ultrasonically treated for 30 min to obtain a modified Ru precursor solution; S3. Add 0.1 g of nitrogen-containing porous carbon material to 100 g of modified Ru precursor solution, disperse evenly and react at 0 ° C for 1 h to obtain a suspension; S4. The suspension was heated at 50°C for 1 h, and then dried at 25°C for 1 h to obtain a solid product; S5. The solid product was calcined in a nitrogen atmosphere (the calcination conditions were: heating to 300°C at a rate of 5°C / min and maintaining for 1 hour) to obtain a Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue, wherein the Ru loading amount was 0.1%.

[0028] Example 8 Preparation method of Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue: S1. Preparation of nitrogen-containing porous carbon material: Toluene diisocyanate waste residue, 1,3-butanediol and ammonium bicarbonate were mixed in a mass ratio of 2:4:1, treated at 170°C for 2h to remove 1,3-butanediol, and then pyrolyzed in a nitrogen atmosphere at 750°C for 2.5h. During the pyrolysis process, a 10% boric acid solution was added to obtain a 0.56wt% nitrogen-containing porous carbon material with a specific surface area of ​​1256m 2 / g, the nitrogen content is 18%, wherein the mass ratio of toluene diisocyanate waste residue to boric acid solution is 9.5:1; S2. Preparation of modified Ru precursor solution: S201. The tetrahydrofuran and the 10% aqueous solution of iron carbonate suspension were mixed and stirred in a mass ratio of 7.6:1 to obtain a primary mixed solution; S202. Add 9% of the mass of glacial acetic acid to the primary mixed solution, stir at 22° C. for 18 min to obtain a modified solution; S203. The mass concentration of 0.12% ruthenium acetylacetonate was mixed with the modified solution in a mass ratio of 1:12.5, and ultrasonically treated for 45 minutes to obtain a modified Ru precursor solution; S3. 18 g of nitrogen-containing porous carbon material was added to 100 g of modified Ru precursor solution, uniformly dispersed and reacted at 55 ° C for 20 h to obtain a suspension; S4. The suspension was heated at 75°C for 5 h, and then dried at 85°C for 40 h to obtain a solid product; S5. The solid product was calcined in a nitrogen atmosphere (the calcination conditions were: heating to 650°C at a rate of 18°C / min and maintaining for 10 hours) to obtain a Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue, wherein the Ru loading amount was 12.5%.

[0029] Performance Test: 1. Test the performance of the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue prepared in Example 1 for thermal catalytic ammonia decomposition and hydrogen production at different reaction temperatures: Weigh three portions of 0.01 g of the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue prepared in Example 1, add 0.06 g of quartz sand to each portion and mix evenly, and add the obtained mixtures to the fixed bed reactor respectively. After the air of the reaction system is purged for 1 hour under 30 ml / min Ar atmosphere, 1 ml / min of ammonia is introduced to carry out ammonia decomposition and hydrogen production reaction, and at the same time, the temperature of the fixed bed reactor is raised to the required temperature, and the product is analyzed by gas chromatograph. The corresponding test results are shown in the attached figure. Figure 4 As shown. Figure 4 It can be seen that the performance of ammonia decomposition and hydrogen production of Ru-based catalyst (Ru / NC) prepared from toluene diisocyanate waste residue and supported by nitrogen-containing porous carbon increases continuously with increasing temperature.

[0030] 2. Test the photothermal catalytic ammonia decomposition and hydrogen production performance of the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue prepared in Example 1 at different reaction temperatures: Weigh three portions of 0.01g of the Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue prepared in Example 1, add 0.06g of quartz sand to each portion for uniform mixing, and add the obtained mixtures to the fixed bed reactor respectively. After the air of the reaction system was purged for 1h under 30ml / min Ar atmosphere, 1ml / min of ammonia was introduced to carry out ammonia decomposition and hydrogen production reaction. At the same time, a 300W xenon lamp was used to irradiate the catalyst through the quartz window of the fixed bed reactor, and the temperature of the fixed bed reactor was raised to the required temperature. The product was analyzed by gas chromatograph at 400, 450 and 500°C, respectively. The corresponding test results are shown in the attached figure. Figure 5 As shown. Figure 4 and attached Figure 5 From the comparison of the results, it can be seen that at the same reaction temperature, the photothermal catalytic ammonia decomposition and hydrogen production performance of the Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue is higher than the thermal catalytic performance.

[0031] 3. Test the photothermal catalytic ammonia decomposition and hydrogen production performance of the Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue prepared in Examples 1-8 and the commercially purchased 5wt% Ru-loaded activated carbon catalyst (commercial Ru / C, Shanghai MacLean Biochemical Technology Co., Ltd.): Weigh 0.01g of the Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue prepared in Examples 1-8 and 0.01g of a commercially purchased 5wt% Ru-loaded activated carbon catalyst, add 4 portions of 0.06g of quartz sand to the above catalysts and mix them evenly, and add the obtained mixtures to the fixed bed reactor. After the air in the reaction system was purged for 1h under 30ml / min Ar atmosphere, 1ml / min of ammonia was introduced to carry out ammonia decomposition and hydrogen production reaction. At the same time, a 300W xenon lamp was used to irradiate the catalyst through the quartz window of the fixed bed reactor, and the temperature of the fixed bed reactor was raised to 500°C. The product was analyzed by gas chromatograph. The corresponding test results are shown in the attached figure. Figure 6 As shown. Figure 6 It can be seen that the Ru-based catalyst prepared from toluene diisocyanate waste residue with nitrogen-containing porous carbon as the carrier has better performance in photothermal ammonia decomposition to produce hydrogen than the commercially purchased catalyst with activated carbon as the carrier.

[0032] 4. Test the photothermal catalytic ammonia synthesis performance of the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue prepared in Example 1 at different reaction temperatures: Weigh three portions of 0.01g of the Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue prepared in Example 1, add 0.06g of quartz sand to each portion for uniform mixing, and add the obtained mixtures to the fixed bed reactor respectively. After the air of the reaction system was purged for 1h under 30ml / min Ar atmosphere, 1.5ml / min of a mixed gas of hydrogen and nitrogen with a volume ratio of 3:1 was introduced to carry out ammonia synthesis reaction, and at the same time, a 300W xenon lamp was used to irradiate the catalyst through the quartz window of the fixed bed reactor. At the same time, the temperature of the fixed bed reactor was raised to the required temperature, and the product was analyzed by gas chromatograph at 400, 450 and 500°C, respectively. The corresponding test results are shown in the attached figure. Figure 7 As shown. Figure 7 It can be seen that the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue can also be used for ammonia synthesis reaction and has bifunctional catalytic properties.

[0033] 5. Test the photothermal catalytic ammonia synthesis performance of the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue prepared in Comparative Example 1 and the commercial Ru / C catalyst: Weigh 0.01g of the Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue prepared in Example 1 and the commercial Ru / C catalyst, add 2 parts of 0.06g of quartz sand and mix them evenly, and add the obtained mixtures into the fixed bed reactor. After the air in the reaction system was purged for 1h under the atmosphere of 30ml / min of Ar gas, 1.5ml / min of a mixed gas of hydrogen and nitrogen with a volume ratio of 3:1 was introduced to synthesize ammonia. At the same time, a 300W xenon lamp was used to irradiate the catalyst through the quartz window of the fixed bed reactor. At the same time, the temperature of the fixed bed reactor was raised to 500°C, and the product was analyzed by gas chromatograph. The corresponding test results are shown in the attached figure. Figure 8 As shown. Figure 8 It can be seen that the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue has better ammonia synthesis performance than the commercial Ru / C catalyst supported on activated carbon at the same temperature.

[0034] The present invention determines the Ru loading and nitrogen content in the prepared catalyst by inductively coupled plasma mass spectrometry (ICP-MS) testing. 2 The specific surface area of ​​the nitrogen-containing porous carbon material is determined by analyzing the adsorption-desorption isotherms. 2Adsorption-desorption isotherms are shown in Figure 2 As shown, Example 1 is attached Figure 2 The a curve in Example 2 is attached Figure 2 b curve in the embodiment 3 is attached Figure 2 The c curve in . Figure 3 Figure 1 is the STEM image of the prepared catalyst and the corresponding element distribution map of C, N, and Ru, where the scale lengths of Figures a, b, c, and d are all 0.5 μm. Figure 3 It can be seen that the three elements of C, N and Ru contained in the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue prepared by toluene diisocyanate waste residue are uniformly distributed in the entire catalyst.

[0035] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue, characterized in that: The following steps are involved: S1. Preparation of nitrogen-containing porous carbon material: toluene diisocyanate waste residue, 1,3-butanediol and ammonium bicarbonate are mixed in a mass ratio of 2:4:1, treated at 100-180°C for 2-5h to remove 1,3-butanediol, pyrolyzed in a nitrogen atmosphere at 600-800°C for 1-3h and a boric acid solution with a mass concentration of 10% is added during the pyrolysis process to obtain a nitrogen-containing porous carbon material; S2. Preparation of modified Ru precursor solution: The Ru precursor and the modified solution were mixed in a mass ratio of 1:10-13, and ultrasonically treated for 30-50 min to obtain a modified Ru precursor solution; S3. Adding 0.1-20% of the nitrogen-containing porous carbon material to the modified Ru precursor solution, uniformly dispersing and reacting, to obtain a suspension; S4. After heating the suspension, drying it at 25-100 ° C for 1-48h to obtain a solid product; S5. The solid product was calcined under a nitrogen atmosphere to obtain a Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue; Wherein, the preparation of the modified liquid comprises the following steps: S201. The tetrahydrofuran and the 10% aqueous solution of iron carbonate suspension were mixed and stirred in a mass ratio of 5-8:1 to obtain a primary mixed solution at a stirring speed of 450-550 r / min; S202. Add glacial acetic acid in an amount of 6-10% of the mass of the preliminary mixed solution to the primary mixed solution, stir at a speed of 450-550 r / min for 15-20 min at 20-23°C to obtain a modified solution.

2. The method for preparing the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue according to claim 1, characterized in that: In step S1, the mass ratio of toluene diisocyanate waste residue to the boric acid solution with a mass concentration of 10% is 8-10:

1.

3. The method for preparing the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue according to claim 1, characterized in that: The specific surface area of ​​the nitrogen-containing porous carbon material obtained in step S1 is 100-1500m 2 / g, nitrogen content is 5-20%.

4. The method for preparing the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue according to claim 1, characterized in that: In step S2, the Ru precursor is one or more of ruthenium trichloride trihydrate, triruthenium dodecacarbonyl, ruthenium nitrosyl nitrate, ruthenium acetylacetonate, potassium ruthenate, and ruthenium acetate.

5. The method for preparing the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue according to claim 1, characterized in that: The reaction temperature in step S3 is controlled at 0-60° C., and the reaction time is 1-24 h.

6. The method for preparing the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue according to claim 1, characterized in that: In step S4, the heating temperature is 50-80° C. and the heating time is 1-6 hours.

7. The method for preparing the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue according to claim 1, characterized in that: In step S5, the calcination conditions are: heating to 300-700°C at a rate of 5-20°C / min and maintaining for 1-12h.

8. The method for preparing the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue according to claim 1, characterized in that: In the Ru-loaded nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue obtained in step S5, the Ru loading amount is 0.1-15%.

9. A Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue, prepared according to the preparation method described in any one of claims 1 to 8.

10. Use of the Ru-supported nitrogen-containing porous carbon bifunctional catalyst based on toluene diisocyanate waste residue according to claim 9 in hydrogen production by decomposition of ammonia and ammonia synthesis.

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