Novel nickel-based catalytic material

Abstract

The invention relates to the technical field of catalytic materials, in particular to a novel nickel-based catalytic material which is prepared from a precursor synthesized from nickel nitrate, hexaamino triphenyl tetracarboxylic acid, distilled water and N, N-dimethylformamide. The invention aims to solve the problems of high cost, poor stability, catalyst poisoning, difficult recovery and the like of the existing catalyst in the catalytic reaction of nitrophenol. According to the novel nickel-based catalytic material, the catalytic material which is low in cost, environmentally friendly and efficient is adopted, and high catalytic activity and good stability can be kept under severe conditions such as high temperature and high pressure. Meanwhile, the nickel-based catalytic material disclosed by the invention has relatively strong anti-poisoning capability, can effectively improve the selectivity and conversion rate of reaction, has excellent recoverability and regeneration performance, can reduce the production cost, reduce resource consumption and environmental pollution, and meets the requirements of large-scale industrial application.

Description

Technical Field

[0001] The present invention relates to the technical field of catalytic materials, and particularly to a novel nickel-based catalytic material. Background Art

[0002] Nitroaniline is an important organic chemical raw material, which is widely used in many fields such as dyes, rubber, plastics, pesticides, pharmaceuticals, and polymer materials. In the dye industry, aniline is used to synthesize indigo dyes and azo dyes, which are widely used in textile and leather dyeing; in the rubber industry, as a vulcanization accelerator to improve the performance of rubber; in pharmaceutical synthesis, it is a precursor for the preparation of drugs such as paracetamol; in addition, aniline is also used in the production of polymer materials such as phenolic resins and polyurethanes, and even plays an important role in the production of certain pesticides and fungicides.

[0003] Industrially, the main preparation method of nitroaniline is through catalytic hydrogenation (catalytic reduction method), that is, under the action of hydrogen and a catalyst, p-nitrophenol is reduced to p-nitroaniline. Currently, the commonly used catalysts are precious metals (such as platinum and palladium), but their high cost and harsh usage conditions limit their wide application. In recent years, novel catalysts such as nanomaterials and metal-organic frameworks (MOFs) have shown excellent catalytic performance due to their large specific surface area and unique structure.

[0004] However, the recyclability, anti-poisoning property, and green sustainability of the catalyst are still the focus of current research. With the improvement of environmental protection requirements and the promotion of the concept of sustainable development, the development of green and efficient catalysts has become an important development direction in this field. Therefore, there is an urgent need for a novel catalytic material with low cost, environmental friendliness, and high efficiency. Summary of the Invention

[0005] To solve the above problems, the present invention provides a novel nickel-based catalytic material, which is used to reduce the production cost of nitroaniline, reduce resource consumption and environmental pollution, and meet the requirements of large-scale industrial applications.

[0006] To achieve the above object, the technical solution of the present invention is as follows: A novel nickel-based catalytic material is prepared from a precursor synthesized from nickel nitrate, hexaaminotriphenyltetracarboxylic acid, distilled water, and N,N-dimethylformamide.

[0007] Furthermore, the raw material preparation for the synthesis of the precursor includes:

[0008] Take 0.03 g of experimental-grade nickel nitrate, 0.010 g of hexaaminotriphenyltetracarboxylic acid, 0.5 mL of distilled water, and 2 mL of N,N-dimethylformamide;

[0009] Add the above reagents to a glass vial and stir until all components are completely dissolved or evenly dispersed.

[0010] Furthermore, the reaction conditions for the precursor synthesis include:

[0011] Seal the glass vial and place it in an oven at 358K for 72 hours;

[0012] Then cool the glass vial to room temperature, precipitate the mother liquor, and obtain green crystals.

[0013] Furthermore, the crystal purification of the precursor synthesis includes:

[0014] Wash the green crystals with N,N-dimethylformamide solvent several times to remove excess reactants and solvents;

[0015] Place the washed green crystals in a vacuum drying oven and dry them under a vacuum environment to obtain a pure precursor.

[0016] Furthermore, the preparation steps of the nickel-based catalytic material include:

[0017] Take 0.2 g of the precursor and grind it to make the particles uniform;

[0018] Put the ground precursor into a vacuum tube furnace, introduce high-purity argon to discharge the air in the tube, and maintain an argon protection environment;

[0019] Heat the vacuum tube furnace to 800 °C at a programmed heating rate and hold for 1 hour to convert the precursor into a nickel-based composite material; then cool the vacuum tube furnace to below 50 °C at a programmed cooling rate;

[0020] Use dilute hydrochloric acid to wash and remove the impurities contained in the nickel-based composite material, and rinse it with distilled water until it is neutral;

[0021] Then put the nickel-based composite material rinsed to neutral into a vacuum drying oven and dry it under a vacuum environment for 3 hours to prepare the nickel-based catalytic material.

[0022] Furthermore, the duration of introducing high-purity argon is greater than or equal to 30 minutes.

[0023] Furthermore, the heating and cooling rates of the vacuum tube furnace are both 5 °C·min-1.

[0024] Advantages of the present invention:

[0025] 1. Improve catalytic activity and selectivity: After using this new catalyst, the catalytic activity of the reaction is significantly improved. This catalyst has a high specific surface area and more active sites, which can effectively enhance the speed and selectivity of the catalytic reaction. Especially in the fields of environmental protection and energy conversion, it can more precisely control the reaction process and reduce the generation of by-products.

[0026] 2. Enhance the stability and anti - poisoning ability of the catalyst: This catalyst can still maintain high stability under harsh conditions such as high temperature and high pressure. Compared with traditional catalysts, it has stronger anti - poisoning ability and can effectively inhibit the poisoning effect of harmful substances in the reaction on the catalyst. This enables the catalyst to maintain high activity and selectivity during long - term use, thereby extending the service life of the catalyst and reducing the need for replacement and regeneration.

[0027] 3. High - efficiency recovery and regeneration performance: Compared with traditional noble - metal catalysts, this catalyst can remove impurities in the reaction through a simple cleaning process and restore its catalytic activity, making it suitable for multiple uses, reducing catalyst waste and resource consumption, and greatly reducing the cost in the production process.

[0028] 4. Environment - friendly and low - cost: This catalyst replaces traditional noble - metal catalysts and has lower production costs. Since nickel is a relatively abundant resource, compared with noble - metal catalysts such as platinum and palladium, its raw material cost is lower. In addition, the preparation process of the catalyst has less environmental impact, contributing to green production and meeting the requirements of modern sustainable development.

[0029] 5. Lower price cost compared with noble - metal catalysts: This catalyst has an obvious advantage in cost. Compared with traditional noble - metal catalysts (such as platinum and palladium), the production cost of this catalyst is lower, mainly because nickel resources are relatively abundant and the price is relatively low. This makes the catalyst more economical in large - scale industrial applications, reducing the overall production cost and making it more competitive in cost - sensitive applications.

[0030] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is the powder X - ray diffraction pattern of the embodiment of the novel nickel - based catalytic material of the present invention;

[0032] Figure 2 It is the Raman spectrum of the nickel - based catalytic material of the embodiment of the novel nickel - based catalytic material of the present invention;

[0033] Figure 3 It is the PXRD spectrum of the nickel - based catalytic material of the embodiment of the novel nickel - based catalytic material of the present invention;

[0034] Figure 4 It is the schematic diagram of the catalytic effect of the reduction reaction of p - nitrophenol of the embodiment of the novel nickel - based catalytic material of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0035] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0036] The following is a further detailed description through specific embodiments:

[0037] A novel nickel-based catalytic material is mainly prepared from a precursor synthesized from nickel nitrate, hexaaminotriphenyltetracarboxylic acid, distilled water, and N,N-dimethylformamide; this nickel-based catalytic material has high catalytic activity, excellent stability, good anti-poisoning ability, and strong recyclability, and can exhibit good performance in the catalytic reduction reaction of nitrophenol.

[0038] The synthesis steps of the precursor of the nickel-based catalytic material in this embodiment are as follows:

[0039] Raw material preparation:

[0040] 1. Take 0.03 g of experimental-grade nickel nitrate, 0.010 g of hexaaminotriphenyltetracarboxylic acid (0.016 mmol), 0.5 mL of distilled water, and 2 mL of DMF (N,N-dimethylformamide).

[0041] 2. Add the above reagents into a 5 mL glass vial and stir with a magnetic stirrer for 30 minutes to ensure that all components are completely dissolved or evenly dispersed.

[0042] Reaction conditions:

[0043] 1. Place the sealed glass vial in an oven at 358 K and react for 72 hours. At this time, the precursor will form green crystals through a self-assembly reaction.

[0044] 2. After the reaction is completed, cool the vial to room temperature, precipitate the mother liquor, and obtain green crystals.

[0045] Crystal purification:

[0046] 1. Wash the green crystals several times with DMF solvent to remove excess reactants and solvents.

[0047] 2. Place the washed green crystals in a vacuum drying oven and dry them in a vacuum environment to obtain a pure precursor.

[0048] The synthesis steps of the nickel-based catalytic material in this embodiment are as follows:

[0049] 1. Take 0.2 g of the precursor and put it into an agate mortar for grinding to make its particles more uniform.

[0050] 2. Put the ground precursor into a vacuum tube furnace.

[0051] 3. Introduce high-purity argon gas (preferably for 30 minutes), exhaust the air in the tube, and maintain an argon gas protection environment.

[0052] 4. Under an argon gas atmosphere, using a programmed temperature increase method, heat the temperature to 800 °C at a heating rate of 5 °C·min-1. Keep this temperature for 1 hour to convert the precursor into a nickel-based composite material with high catalytic performance.

[0053] 5. Then, reduce the furnace temperature to below 50 °C at a rate of 5 °C·min-1 to end the calcination process.

[0054] 6. After taking out the nickel-based composite material, wash it with dilute hydrochloric acid to remove possible impurities in the nickel-based composite material, and rinse it with distilled water until it is neutral.

[0055] 7. Finally, put the nickel-based composite material into a vacuum drying oven and dry it in a vacuum environment for 3 hours to finally obtain the target catalyst, namely the nickel-based catalytic material.

[0056] The novel nickel-based catalytic material of this embodiment is further described with reference to the accompanying drawings:

[0057] Figure 1 Shown is the powder X-ray diffraction pattern. The PXRD spectrum of the prepared precursor is highly consistent with the simulated structure spectrum, and the peak positions are precisely matched, indicating that the synthesized crystal has a high purity and no impurities are detected.

[0058] Figure 2 Shown is the Raman spectrum of the nickel-based catalytic material. The composite material has characteristic peaks at 1361 cm-1 (D band) and 1696 cm-1 (G band). The D band is related to the defects and edge hybridization vibrations of the carbon material, and the G band is related to the in-plane stretching vibration of sp 2 carbon atoms. By analyzing the intensity ratio of the D band to the G band (ID / IG), information on the defect density can be obtained. A higher ID / IG ratio indicates a higher defect density, and it is speculated that the material has a better degree of graphitization, which helps to improve the catalytic performance.

[0059] Figure 3 Shown is the PXRD spectrum of the nickel-based catalytic material. The PXRD pattern of this material shows two obvious diffraction peaks at 2θ = 44.2° and 2θ = 51.2° respectively, indicating the presence of metal nanoparticles in the catalyst. The diffraction peaks have a narrow peak width and high intensity, further supporting the high crystallinity and large size distribution of the metal nanoparticles.

[0060] Figure 4The catalytic effect diagram of the reduction reaction of p-nitrophenol is shown. In this example, the catalytic performance of the catalyst was evaluated by using the catalytic reduction reaction of sodium borohydride on p-nitrophenol (4-NP). The metal nanoparticles served as electron transfer sites and provided the active sites for the reduction process. Under the condition of excessive sodium borohydride, this reaction follows the first-order reaction kinetics, and the reaction progress was monitored by observing the change in the intensity of the characteristic peak at 400 nm through UV-Vis spectroscopy. At the beginning of the reaction, the solution was yellow. As the reduction reaction proceeded, the color gradually faded and finally became colorless. When the reaction was completed, the control experiment showed that there was no obvious catalytic effect without the catalyst or with only activated carbon. The catalyst in this example could catalyze the reaction quickly and timely, showing good catalytic effect.

[0061] Obviously, the above examples are only for illustration and are not intended to limit the implementation methods. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A new type of nickel-based catalytic material, characterized in that: The nickel-based catalytic material is prepared from precursors synthesized from nickel nitrate, hexaminotriphenyltetracarboxylic acid, distilled water and N,N-dimethylformamide.

2. The novel nickel-based catalytic material according to claim 1, characterized in that: The raw material preparation for precursor synthesis includes: Take 0.03 g of experimental grade nickel nitrate, 0.010 g of hexamethylenetriphenyltetracarboxylic acid, 0.5 mL of distilled water and 2 mL of N,N-dimethylformamide; Add the above reagents into a glass vial and stir until each component is completely dissolved or evenly dispersed.

3. The novel nickel-based catalytic material according to claim 2, characterized in that: The glass vial had a capacity of 5 ml and was stirred with a magnetic stirrer for 30 minutes.

4. The novel nickel-based catalytic material according to claim 2, characterized in that: The reaction conditions for precursor synthesis include: The glass vial was sealed and placed in an oven at 358 K for 72 h; The glass vial was then cooled to room temperature, the mother liquor was precipitated, and green crystals were obtained.

5. The novel nickel-based catalytic material according to claim 4, characterized in that: Crystal purification of precursor synthesis includes: The green crystals were washed several times with N,N-dimethylformamide solvent to remove excess reactants and solvent; The washed green crystals are placed in a vacuum drying oven and dried under a vacuum environment to obtain a pure precursor.

6. The novel nickel-based catalytic material according to any one of claims 1 to 5, characterized in that: The preparation steps of the nickel-based catalytic material include: Take 0.2 g of the precursor and grind it to make the particles uniform; The ground precursor is placed in a vacuum tube furnace, high-purity argon gas is introduced, the air in the tube is exhausted, and the argon gas is maintained to protect the environment; The vacuum tube furnace is heated to 800°C by a programmed temperature rising method and maintained for 1 hour to convert the precursor into a nickel-based composite material; the vacuum tube furnace is then cooled to below 50°C by a programmed temperature falling method; The impurities contained in the nickel-based composite material are removed by washing with dilute hydrochloric acid, and then rinsed with distilled water until it becomes neutral; The nickel-based composite material rinsed to neutrality is then placed in a vacuum drying oven and dried under vacuum for 3 hours to obtain a nickel-based catalytic material.

7. The novel nickel-based catalytic material according to claim 6, characterized in that: The duration of introducing high-purity argon gas is greater than or equal to 30 minutes.

8. The novel nickel-based catalytic material according to claim 6, characterized in that: The heating and cooling rates of the vacuum tube furnace are both 5℃·min-1.

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