3D printing nickel-based micro-reactor, preparation method and application thereof

Abstract

The present application relates to a kind of 3D printing nickel-based microreactor and its preparation method and application.Nickel-based superalloy is used as precursor material, and the reactor entity is prepared using metal 3D printing;Wherein the 3D printing nickel-based microreactor prepared has reciprocating ring around single-channel pipeline structure.The microreactor has catalytic performance, the reactor is subjected to high-temperature calcination treatment and is used in ammonia decomposition reaction, has good catalytic activity at ammonia decomposition test temperature, and maintains good stability in catalytic stability test.

Description

Technical Field

[0001] This invention belongs to the field of catalysis, specifically relating to a 3D-printed nickel-based microreactor, its preparation method, and its application. Background Technology

[0002] With the continuous development and research of hydrogen energy, the storage and transportation of hydrogen has attracted widespread attention. Direct compression and storage of hydrogen is costly and dangerous, while in-situ hydrogen production can effectively solve these problems. Numerous studies have shown that using ammonia as a hydrogen carrier, decomposition under the action of a catalyst can achieve online hydrogen production, decomposing NH3 into N2 and H2 without other decomposition products. In traditional technologies, catalysts and reactors for ammonia decomposition remain two different research directions. Research on reactors mainly focuses on improving the mass transfer and heat transfer properties of the material; research on catalysts mainly focuses on improving the performance of ammonia decomposition at low temperatures and enhancing catalyst stability. Summary of the Invention

[0003] The purpose of this invention is to provide a 3D-printed nickel-based microreactor, its preparation method, and its application, which solves the problem of complex reactor preparation processes in the existing ammonia decomposition technology field. The nickel-based microreactor prepared by the method of this invention has good catalytic activity, providing a solution for in-situ ammonia decomposition to produce hydrogen.

[0004] To achieve the above objectives, the technical solution of the present invention is as follows:

[0005] One of the objectives of this invention is to provide a method for preparing a 3D-printed nickel-based microreactor. Using a nickel-based high-temperature alloy as a precursor material, the nickel-based microreactor is fabricated using metal 3D printing. The nickel-based microreactor is then subjected to high-temperature calcination and applied to an ammonia decomposition reaction. This nickel-based microreactor exhibits catalytic performance.

[0006] Furthermore, the method for preparing the 3D-printed nickel-based microreactor includes the following steps:

[0007] (1) Using computer-aided design software, a digital model of a nickel-based microreactor was designed;

[0008] (2) Using a metal 3D printer, nickel-based high-temperature alloys were added as printing materials to obtain nickel-based microreactor entities;

[0009] (3) Cut and polish the reactor body made in step (2) to obtain a nickel-based microreactor.

[0010] Furthermore, the nickel-based microreactor prepared in step (3) is subjected to high-temperature calcination.

[0011] Furthermore, in step (3), the high-temperature calcination temperature is 700~900℃ and the calcination time is 6~24h.

[0012] The second objective of this invention is to provide a 3D-printed nickel-based microreactor prepared according to the above method.

[0013] Furthermore, the nickel-based microreactor has a reciprocating single-channel pipeline, which spirals from the inside out. The nickel-based microreactor is equipped with a reaction gas inlet pipeline and an outlet pipeline, and the inside of the pipeline is provided with micro-hemispherical protrusions.

[0014] The third objective of this invention is to apply 3D-printed nickel-based microreactors to ammonia decomposition for hydrogen production, wherein the nickel-based microreactors have catalytic properties.

[0015] Furthermore, a nickel-based microreactor was directly used for ammonia decomposition. The reaction temperature for ammonia decomposition in the nickel-based microreactor was 450–700 °C, and the flow rate of the reactant gas was 40–70 mL / min. -1 .

[0016] Furthermore, a hydrogen-argon mixture is introduced into the nickel-based reactor for reaction pretreatment.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The preparation method of the nickel-based microreactor in this invention is simple. The sample is directly printed by 3D printing SLM method with high fidelity. The reactor has catalytic performance and can be directly used for catalytic reaction without the need to add catalyst to the reaction equipment.

[0019] 2. The reactor prepared by this invention using 3D printing technology has a reciprocating single-channel structure, with the pipeline spiraling from the inside out. The nickel-based microreactor is equipped with a gas inlet pipeline and a gas outlet pipeline. During the ammonia decomposition reaction, the gas flows from top to bottom and then from bottom to top, prolonging the contact time between ammonia and the catalyst. The pipeline is equipped with micro-hemispherical protrusions to increase gas turbulence and the gas-metal contact area, thereby improving the catalytic efficiency of the entire ammonia decomposition process.

[0020] 3. The nickel-based microreactor prepared by this invention achieves the effect of autocatalytic ammonia decomposition and exhibits high catalytic activity. It can stably achieve 100% conversion of ammonia at 650℃ and an ammonia flow rate of 50mL / min. After a stability test of 50h at 650℃ and an ammonia flow rate of 50mL / min, the ammonia conversion rate can be maintained above 99%.

[0021] 4. The preparation method of the present invention has strong environmental adaptability. The 3D printed autocatalytic reactor is not limited to this one morphology. According to the actual environmental needs, the model can be digitally adjusted to produce samples that can adapt to the current environment. Attached Figure Description

[0022] Figure 1 Figure 1 is a schematic diagram of the digital model of the 3D-printed nickel-based microreactor prepared in this invention; Figure 2 is a top view of the reactor; Figure 3 is a cross-sectional view of the reactor; Figure 4 is a front view of the reactor.

[0023] Figure 2 Figure 1 shows a physical image of the 3D-printed nickel-based microreactor prepared according to the present invention; Figure 2 shows a physical image of the uncalcined microreactor; Figure 3 shows a physical image of the microreactor after calcination at 700°C for 6 hours.

[0024] Figure 3 The image shows the catalytic activity data of the 3D-printed nickel-based microreactor prepared in this invention under the conditions of 450~700℃ and ammonia flow rate of 40~70mL / min.

[0025] Figure 4 The stability performance of the 3D-printed nickel-based microreactor prepared in this invention is shown in the figure at 650℃ and an ammonia flow rate of 50 mL / min.

[0026] Figure 5 A comparison of the catalytic performance of 3D-printed nickel-based microreactors that are uncalcined and calcined at 700℃. Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings and preferred embodiments. The embodiments given are only for illustrating the present invention and are not intended to limit the scope of the present invention.

[0028] Unless otherwise specified, all materials and reagents used in the following examples are commercially available.

[0029] In the quantitative experiments in the following examples, three replicate experiments were set up, and the average value of the results was taken.

[0030] Unless otherwise specified, the experimental methods described in the following examples are conventional methods.

[0031] Example 1

[0032] A method for preparing a 3D-printed nickel-based microreactor, using a nickel-based superalloy as a precursor material, fabricating the reactor entity using metal 3D printing, subjecting the reactor to high-temperature calcination, and applying it to an ammonia decomposition reaction, specifically includes the following steps:

[0033] (1) Model the nickel-based microreactor using computer-aided design software, import the model file into the computer software, and check the digital model;

[0034] (2) Import the digital model into the 3D printer to convert the digital model into a physical model. For example... Figure 1 As shown, the nickel-based microreactor physical model in this embodiment has a reciprocating single-channel pipeline structure. The pipeline spirals from the inside out, with a gas inlet pipeline and a gas outlet pipeline at the top and bottom ends, respectively. The gas flows from top to bottom and then from bottom to top. The inside of the pipeline is provided with micro-hemispherical protrusions to increase gas turbulence and the contact area between the gas and the metal.

[0035] (3) The nickel-based microreactor entity prepared in step (2) is cut and polished to obtain the nickel-based microreactor. The reactor is then subjected to high-temperature calcination treatment, calcined at 700℃ for 6 hours in air atmosphere, with a heating rate of 2℃ / min, to finally obtain the nickel-based microreactor, as shown below. Figure 2 As shown in (b).

[0036] Example 2

[0037] The difference between Example 2 and Example 1 is that the structure of the digital model of the nickel-based microreactor made by 3D printing technology can be adjusted according to the needs of the actual environment, such as strip structure, stepped structure or other shape structure; the nickel-based microreactor entity is calcined in a muffle furnace at a high temperature of 800℃ for 7h, with a heating rate of 2℃ / min.

[0038] Example 3

[0039] The difference between Example 3 and Example 1 is that the 3D printed nickel-based microreactor entity was calcined in a muffle furnace at a high temperature of 900°C for 8 hours with a heating rate of 2°C / min.

[0040] Example 4

[0041] The 3D-printed nickel-based microreactor prepared according to Example 1 was used in the ammonia decomposition reaction. In-situ reduction was performed at 500°C with a 50% H2 / Ar mixture for 20 hours; subsequently, Ar gas was introduced for purging for 30 minutes to eliminate interference from residual H2 in the pipeline. A programmed temperature ramp was set, and NH3 gas was introduced. Catalytic activity was tested at temperature points of 450, 500, 550, 600, 650, and 700°C, with NH3 flow rates of 40, 50, 60, and 70 mL / min. Figure 3 As can be seen, ammonia can be completely decomposed at 650℃.

[0042] Example 5

[0043] The 3D-printed nickel-based microreactor fabricated according to Example 1 was used in the ammonia decomposition reaction. In-situ reduction was performed at 500°C with a 50% H2 / Ar mixture for 20 hours; subsequently, Ar gas was introduced for purging for 30 minutes to eliminate interference from residual H2 in the pipeline. A programmed temperature ramp was set, and NH3 gas was introduced. The nickel-based microreactor was then subjected to catalytic stability testing at 650°C and an NH3 flow rate of 50 mL / min for 50 hours. Figure 4 It can be seen that during the 50-hour test, the nickel-based microreactor can still achieve an ammonia decomposition conversion rate of over 99%.

[0044] Comparative Example 1

[0045] The difference between Comparative Example 1 and Example 1 is that the 3D-printed nickel-based microreactor was not subjected to high-temperature calcination, such as... Figure 2 As shown in (a). The reactors prepared in the comparative example and Example 1 were used for ammonia decomposition reaction. In-situ reduction was performed at 500°C with a 50% H2 / Ar mixed gas for 20 h; subsequently, Ar gas was introduced for purging for 30 min to eliminate interference from residual H2 in the pipeline. A programmed temperature rise was set, and NH3 gas was introduced. The nickel-based microreactor was tested for catalytic activity at temperatures of 450, 500, 550, 600, 650, and 700°C, with an NH3 flow rate of 50 mL / min. Performance comparisons were made. Figure 5 As shown. From Figure 5 It was found that the catalytic performance of an uncalcined reactor is lower than that of a calcined reactor.

[0046] The above are preferred embodiments of the present invention. Any changes made to the technical solution of the present invention that do not exceed the scope of the technical solution of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for preparing a 3D-printed nickel-based microreactor, characterized in that, Using nickel-based superalloys as precursor materials, a nickel-based microreactor is fabricated using metal 3D printing. This nickel-based microreactor has catalytic properties and does not require the addition of a catalyst. The nickel-based microreactor has a reciprocating single-channel pipeline, and the overall direction of the pipeline is spiraling from the inside to the outside. The nickel-based microreactor is provided with a reaction gas inlet pipeline and an outlet pipeline, and the inside of the pipeline is provided with micro-hemispherical protrusions.

2. The method for preparing a 3D-printed nickel-based microreactor according to claim 1, characterized in that, Includes the following steps: (1) Using computer-aided design software, a digital model of a nickel-based microreactor was designed; (2) Using a metal 3D printer, nickel-based high-temperature alloys were used as printing materials to obtain nickel-based microreactor entities; (3) Cut and polish the nickel-based microreactor entity made in step (2) to finally obtain the nickel-based microreactor.

3. The method for preparing a 3D-printed nickel-based microreactor according to claim 2, characterized in that, In step (3), the prepared nickel-based microreactor is subjected to high-temperature calcination.

4. The method for preparing a 3D-printed nickel-based microreactor according to claim 3, characterized in that, In step (3), the high-temperature roasting temperature is 700~900℃ and the time is 6~24h.

5. An application of a 3D-printed nickel-based microreactor, characterized in that, The application of the nickel-based microreactor prepared by any one of the preparation methods described in claims 1-4 in the ammonia decomposition for hydrogen production, wherein the nickel-based microreactor has catalytic performance.

6. The application of the 3D-printed nickel-based microreactor according to claim 5, characterized in that, Nickel-based microreactors are used directly as reaction devices for ammonia decomposition. The reaction temperature for ammonia decomposition using nickel-based microreactors is 450~700℃.

7. The application of the 3D-printed nickel-based microreactor according to claim 5, characterized in that, The nickel-based microreactor is pretreated by introducing a hydrogen-argon mixture.

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