Continuous flow preparation device for carbon-loaded gold nanoparticle catalyst

Abstract

The utility model relates to the field of nano material synthesis, in particular to a continuous flow preparation device of a carbon-loaded gold nanoparticle catalyst, which comprises four raw material solution containers for providing four reaction raw material solutions of a gold salt solution, a reducing agent, carbon powder and a settling agent; an inlet of the peristaltic pump is communicated with the four raw material solution containers, and the peristaltic pump is used for providing power for continuous conveying of the four reaction raw material solutions; an inlet of the mixing pipe is communicated with an outlet of the peristaltic pump, and the mixing pipe is used for mixing the raw material solution entering the mixing pipe; an inlet of the finished product container is communicated with an outlet of the mixing pipe, and the finished product container is used for containing a prepared carbon-loaded gold nanoparticle catalyst finished product. According to the invention, four raw material solutions are continuously conveyed and reacted in the container, manual operation of workers is reduced in the whole process, and the purposes of improving the production efficiency of the carbon-loaded gold nanoparticle catalyst and the consistency of product quality and having a good industrial application prospect are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of nanomaterial synthesis, and particularly to a continuous flow preparation device for carbon-supported gold nanoparticle catalysts. BACKGROUND

[0002] Currently, carbon-supported gold nanoparticles are a kind of highly efficient catalysts, which are widely used in organic synthesis, environmental governance, fuel cells and other fields. This catalyst combines the high catalytic activity of gold nanoparticles with the good stability and large specific surface area of carbon materials, making it perform well in many catalytic reactions, such as CO oxidation, water-gas shift reaction, selective oxidation of alcohols, etc.

[0003] The current method for preparing carbon-supported gold nanoparticle catalysts is mainly intermittent synthesis. However, intermittent synthesis relies on manual operation and human judgment, and the conditions for each preparation are difficult to be completely consistent, resulting in large differences in particle size, distribution, loading, etc. between different batches of products, poor consistency and stability of the products, and difficulty in meeting the requirements of large-scale industrial production.

[0004] Therefore, it is urgent to propose a device for continuous flow preparation of carbon-supported gold nanoparticle catalysts to solve the problems of poor product consistency and difficulty in large-scale production in the preparation process of carbon-supported gold nanoparticle catalysts. CONTENT OF THE INVENTION

[0005] In order to improve the production efficiency and consistency of product quality of carbon-supported gold nanoparticle catalysts, and have good industrial application prospects, the present application provides a continuous flow preparation device for carbon-supported gold nanoparticle catalysts.

[0006] The continuous flow preparation device for carbon-supported gold nanoparticle catalysts provided by the present application adopts the following technical scheme:

[0007] A continuous flow preparation device for carbon-supported gold nanoparticle catalysts, comprising,

[0008] Four raw material solution containers for providing four kinds of reaction raw material solutions of gold salt solution, reducing agent, carbon powder and settling agent;

[0009] A peristaltic pump, the inlet of which is in communication with the four raw material solution containers, for providing power for the continuous transportation of the four kinds of reaction raw material solutions;

[0010] A mixing pipe, the inlet of which is in communication with the outlet of the peristaltic pump, for mixing the raw material solutions entering the mixing pipe; and

[0011] A finished product container, the inlet of which is in communication with the outlet of the mixing pipe, for containing the prepared carbon-supported gold nanoparticle catalyst finished product.

[0012] Optionally, the mixing tube comprises a mixing tube I, a mixing tube II and a mixing tube III, the inlet of the mixing tube I is in communication with the solution pipe of the outlet of the peristaltic pump for transmitting the gold salt solution and the reducing agent, the outlet of the mixing tube I and the solution pipe of the outlet of the peristaltic pump for transmitting the carbon powder are respectively in communication with the inlet of the mixing tube II, the outlet of the mixing tube II and the solution pipe of the outlet of the peristaltic pump for transmitting the precipitant are respectively in communication with the inlet of the mixing tube III, and the outlet of the mixing tube III is in communication with the inlet of the finished product container.

[0013] Optionally, a three-way joint is arranged between the mixing tube and the solution pipe of the outlet of the peristaltic pump, the three-way joint comprises a three-way joint I, a three-way joint II and a three-way joint III, the three-way joint I is in communication with the inlet of the mixing tube I, the three-way joint II is in communication with the outlet of the mixing tube I and the inlet of the mixing tube II, and the three-way joint III is in communication with the outlet of the mixing tube II and the inlet of the mixing tube III.

[0014] Optionally, a helical blade for disturbing the laminar flow of the fluid is arranged inside the mixing tube, and the helical blade is fixedly connected with the inner wall of the mixing tube.

[0015] Optionally, a temperature sensor is arranged on the side wall of the mixing tube.

[0016] Optionally, a flow meter is further arranged between the peristaltic pump and the mixing tube, the inlet of the flow meter is in communication with the outlet of the peristaltic pump, and the outlet of the flow meter is in communication with the mixing tube.

[0017] Optionally, a connecting pipe for conveying the four raw material solutions is connected with the four raw material solution peristaltic pumps, and the connecting pipe is made of silica gel hose material.

[0018] Optionally, the connecting pipe for conveying the reducing agent is a short pipe, the length of the short pipe is smaller than that of the connecting pipes for conveying the other three raw material solution containers, and the inner diameter of the short pipe is also smaller than that of the connecting pipes for conveying the other three raw material solution containers.

[0019] Optionally, the peristaltic pump is provided with a damping member for reducing vibration when the peristaltic pump is running.

[0020] In summary, the present application has at least one of the following beneficial technical effects:

[0021] 1. By cooperating the four raw material solution containers, the peristaltic pump, the mixing tube and the finished product container, the four raw material solutions in the containers are continuously conveyed and reacted, the manual operation of workers is reduced, the production efficiency of the carbon-loaded gold nanoparticle catalyst is improved, the consistency of the product quality is improved, and the industrial application prospect is good.

[0022] 2. By using a short pipe for the connecting pipe that transports the reducing agent, the length of the pipe is shortened, the radius of the pipe is reduced, and the residence time of the reducing agent in the pipe is reduced, so that the reaction with the gold salt solution is completed before small bubbles form cavities, and the fluid continuity of the reducing agent pipe is ensured;

[0023] 3. By providing a spiral blade structure in the mixing pipe, the laminar flow of the fluid can be effectively disrupted, the mixing is promoted, the reaction process is accelerated, and the reaction efficiency is improved. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a structural schematic diagram of a continuous flow preparation device in the embodiment of the present application;

[0025] Figure 2 is a simple schematic diagram of the reaction sequence of the continuous flow preparation in the embodiment of the present application;

[0026] Figure 3 is a structural schematic diagram of the continuous flow preparation device in the embodiment of the present application.

[0027] BRIEF DESCRIPTION OF DRAWINGS 1, raw material solution container; 2, peristaltic pump; 21, shock pad; 3, flow meter; 4, mixing pipe; 41, mixing pipe I; 42, mixing pipe II; 43, mixing pipe III; 5, finished product container; 6, connecting pipe; 61, first connecting pipe; 62, second connecting pipe; 621, short pipe; 63, third connecting pipe; 7, three-way joint; 71, three-way joint I; 72, three-way joint II; 73, three-way joint III. DETAILED DESCRIPTION

[0028] The following will be described in detail in combination with the drawings Figures 1-3 The present application will be further described in detail.

[0029] The preparation principle of the carbon-supported gold nanoparticle catalyst is that four raw materials, namely, a gold salt solution, a reducing agent, carbon powder, and a settling agent, are chemically reacted. The gold salt solution serves as a gold source and provides gold ions needed for the preparation of gold nanoparticles. The reducing agent reduces Au 3+The ions are reduced to zero-valent gold (AuO) to form gold nanoparticles. The carbon powder acts as a carrier to support the gold nanoparticles, and the carbon powder provides a large specific surface area, which helps the gold nanoparticles to be uniformly distributed on its surface, thereby improving the dispersion and stability of the catalyst. The settling agent helps the gold nanoparticles to be better deposited on the carbon powder, improving the loading efficiency. During the operation, first, the aqueous gold salt solution is mixed with the reducing agent to start the reduction reaction to form gold nanoparticles; during the reduction process, the carbon powder and the settling agent are added, and the gold nanoparticles will gradually deposit on the surface of the carbon powder; after the reaction is completed, the carbon powder loaded with gold nanoparticles is separated by centrifugation or filtration and the like, and is washed to remove unreacted raw materials and by-products; finally, the obtained carbon-supported gold nanoparticle catalyst is dried, and may need to be activated to improve its catalytic performance.

[0030] The embodiment of the present application discloses a continuous flow preparation device for carbon-supported gold nanoparticle catalyst. Figure 1 and Figure 2 The continuous flow preparation device for carbon-supported gold nanoparticle catalyst sequentially comprises four raw material solution containers 1, a peristaltic pump 2, a flow meter 3, a mixing pipe 4, and a finished product container 5. The four solution containers are in communication with the inlets of the peristaltic pump 2, the outlet of the peristaltic pump 2 is in communication with the flow meter 3, the mixing pipe 4 is arranged between the flow meter 3 and the finished product container 5 and is in communication with both through a connecting pipe 6. The four raw materials for preparing the carbon-supported gold nanoparticle catalyst are continuously flowed out from the four raw material solution containers 1 under the pressure delivery of the peristaltic pump 2, and then the mixing reaction is sequentially completed by using the mixing pipe 4 after being regulated by the flow meter 3. The whole process reduces the manual operation of workers, improves the production efficiency of the carbon-supported gold nanoparticle catalyst, and achieves the consistency of product quality and good industrial application prospect.

[0031] Referring to Figure 3 The first connecting pipes 61 are arranged between the four raw material solution containers 1 and the peristaltic pump 2, one end of each of the four first connecting pipes 61 is fixedly connected with and in communication with the liquid outlet of each of the four raw material solution containers 1, and the other end is fixedly connected with and in communication with the four inlets of the peristaltic pump 2. The first connecting pipe 61 is preferably 20-30 cm in the embodiment. The peristaltic pump 2 provides power for the transportation of the four raw materials. Under the action of the peristaltic pump 2, the gold salt solution, the reducing agent, the carbon powder dispersion, and the settling agent are continuously flowed out from the four raw material solution containers 1.

[0032] Referring to Figure 3The outlet of the peristaltic pump 2 is provided with four second connecting pipes 62, one end of each of the four second connecting pipes 62 is fixedly connected with and communicates with one of the four outlets of the peristaltic pump 2, and the other end of each of the four second connecting pipes 62 is fixedly connected with and communicates with one of the four flow meters 3, the four kinds of raw material solutions flow through the peristaltic pump 2 and the second connecting pipes 62 to the flow meters 3, and the second connecting pipes 62 are preferably 20-30 cm in length in this embodiment.

[0033] In this embodiment, the reducing agent is a mixed solution of sodium citrate and sodium borohydride, and sodium borohydride is unstable and will hydrolyze to release hydrogen in an aqueous solution to form small bubbles, which will gradually gather to form a gas cavity, resulting in discontinuity of the reducing agent pipeline fluid. The discontinuity of the reducing agent will directly lead to the increase in the size of the gold nanoparticles and the uneven particle size distribution, and ultimately affect the product consistency and performance of the carbon-supported gold nanoparticle catalyst. In order to solve the problem of gas cavity in the reducing agent pipeline, the first connecting pipe 61 and the second connecting pipe 62 connected to the reducing agent raw material solution container 1 are provided with a short pipe 621, the length of the short pipe 621 is smaller than that of the first connecting pipe 61 and the second connecting pipe 62 connected to the other three kinds of raw material solution containers 1, and the length of the short pipe 621 is preferably 10 cm, so as to reduce the residence time of the reducing agent in the pipeline and complete the reaction with the gold salt solution before the small bubbles form a gas cavity; in addition, the inner diameter of the short pipe 621 is also smaller than that of the other first connecting pipes 61 and second connecting pipes 62, so that the fluid flow rate of the small-diameter silica gel pipe is large under the same flow rate, the residence time in the pipeline is short, and the gas cavity is not easy to form.

[0034] The peristaltic pump 2 will vibrate during operation, and the vibration will promote the hydrolysis of sodium borohydride. In order to reduce the gas cavity in the reducing agent pipeline, a damping member can also be additionally provided on the peristaltic pump 2, which can be a damping pad 21 installed between the bottom of the peristaltic pump 2 and the operating table, and the two sides of the damping pad 21 abut against the peristaltic pump 2 and the operating table, respectively; the damping member can also be an elastic band, one end of which is fixed at a high position and the other end of which is fixedly connected with the peristaltic pump 2, so that the peristaltic pump 2 is separated from the operating table and hung above the operating table, and the elastic band can be made of spring or rubber band material, which can absorb the vibration when the peristaltic pump 2 vibrates. The damping member reduces the vibration of the peristaltic pump 2 during operation, prevents the hydrolysis of sodium borohydride, and ensures the continuity and stability of the reactants.

[0035] Referring to Figure 2 and Figure 3The outlet of each of the four flowmeters 3 is fixedly connected with a third connecting pipe 63, and one end of each of the four third connecting pipes 63 is in communication with the four flowmeters 3 respectively. Three mixing pipes 4 are provided, namely a mixing pipe I 41, a mixing pipe II 42 and a mixing pipe III 43. The mixing pipes 4 are connected with the third connecting pipes 63 through three-way joints 7, and the three-way joints 7 are also provided with three, namely a three-way joint I 71, a three-way joint II 72 and a three-way joint III 73. Two third connecting pipes 63 for transmitting gold salt solution and reducing agent are connected with two ends of the three-way joint I 71 respectively, and the third end is connected with the inlet of the mixing pipe I 41. The outlet of the mixing pipe I 41 and the third connecting pipe 63 for transmitting carbon powder dispersion liquid are connected with two ends of the three-way joint II 72 respectively, and the third end is connected with the inlet of the mixing pipe II 42. The outlet of the mixing pipe II 42 and the third connecting pipe 63 for transmitting settling agent are connected with two ends of the three-way joint III 73 respectively, and the third end is connected with the inlet of the mixing pipe III 43. The outlet of the mixing pipe III 43 and the inlet of the product container 5 are connected.

[0036] The connecting pipes 6 include first connecting pipes 61, second connecting pipes 62 and third connecting pipes 63. In the embodiment, the connecting pipes 6 are preferably silica gel hoses. The silica gel hoses have good resistance to most chemical reagents and are not easy to be corroded, and are suitable for transmitting various acids, alkalis, organic solvents and the like. The silica gel hoses have good flexibility, are easy to bend and install, and the color is usually transparent or translucent, so that the flow of liquid or bubbles in the pipes can be observed.

[0037] The mixing pipes 4 adopt static mixers, which are internally designed with spiral blades, corrugated plates and the like, can effectively disrupt the laminar flow of fluid, promote mixing, accelerate the reaction process and improve the reaction efficiency.

[0038] With reference to Figure 3 A stirrer is arranged in the raw material solution container 1 of the carbon powder dispersion liquid, and the stirrer is vertically arranged at the top outlet of the raw material solution container 1 of the carbon powder dispersion liquid. The stirring end of the stirrer extends into the raw material solution container 1 of the carbon powder dispersion liquid to stir the carbon powder dispersion liquid, so that the carbon powder dispersion liquid is not settled under static condition, the carbon powder concentration at the top and the bottom of the dispersion liquid is inconsistent, and the consistency of the product is affected.

[0039] Small temperature sensors are installed on the side walls of the three mixing pipes 4 to monitor the temperature change in real time, and measures are taken to maintain the temperature, so that the reaction is carried out at the optimum temperature, and the reaction selectivity and product quality are improved.

[0040] The implementation principle of the continuous flow preparation device of the carbon-supported gold nanoparticle catalyst according to the embodiment of the application is as follows: four raw materials, namely, a gold salt solution with a required concentration, a reducing agent, a carbon powder dispersion liquid and a precipitant, are prepared and respectively filled into corresponding raw material solution containers 1; then, the raw material solution containers 1, a peristaltic pump 2, a flow meter 3, a mixing pipe 4 and a finished product container 5 are sequentially connected according to the reaction order by using silica gel hoses, so as to form a complete continuous flow preparation device; then, the peristaltic pump 2 is started, the flow rates of the pipelines are adjusted to the specified values, the four raw materials are sequentially mixed and reacted, and finally, the reaction product, a gold carbon catalyst solution, is collected, so as to obtain a high-quality carbon-supported gold nanoparticle catalyst, and the purpose of improving the production efficiency of the carbon-supported gold nanoparticle catalyst, the consistency of the product quality and the good industrial application prospect is achieved.

[0041] The above are preferred embodiments of the application, and do not limit the protection scope of the application, so: equivalent changes made according to the structure, shape and principle of the application should be covered within the protection scope of the application.

Claims

1. A continuous flow apparatus for the preparation of carbon supported gold nanoparticle catalysts, characterised in that: The application relates to a gold-carbon nanometer particle catalyst preparation device, which comprises the following components: four raw material solution containers (1) for providing four reaction raw material solutions of gold salt solution, reducing agent, carbon powder and precipitant; a peristaltic pump (2) in communication with the four raw material solution containers (1) for providing power for the continuous delivery of the four reaction raw material solutions; a mixing pipe (4) in communication with the outlet of the peristaltic pump (2) for mixing the raw material solutions entering the mixing pipe (4); and a finished product container (5) in communication with the outlet of the mixing pipe (4) for containing the prepared carbon-gold nanometer particle catalyst finished product. The mixing pipe (4) comprises a mixing pipe I (41), a mixing pipe II (42) and a mixing pipe III (43), the inlet of the mixing pipe I (41) is in communication with the solution pipe of the peristaltic pump (2) outlet for transmitting the gold salt solution and the reducing agent, the outlet of the mixing pipe I (41) and the solution pipe of the peristaltic pump (2) outlet for transmitting the carbon powder are respectively in communication with the inlet of the mixing pipe II (42), the outlet of the mixing pipe II (42) and the solution pipe of the peristaltic pump (2) outlet for transmitting the precipitant are respectively in communication with the inlet of the mixing pipe III (43), and the outlet of the mixing pipe III (43) is in communication with the inlet of the finished product container (5).

2. The continuous flow device for the preparation of carbon supported gold nanoparticle catalyst according to claim 1, characterized in that: A three-way joint (7) is arranged between the mixing pipe (4) and the solution pipe of the peristaltic pump (2) outlet, the three-way joint (7) comprises a three-way joint I (71), a three-way joint II (72) and a three-way joint III (73), the three-way joint I (71) is in communication with the inlet of the mixing pipe I (41), the three-way joint II (72) is in communication with the outlet of the mixing pipe I (41) and the inlet of the mixing pipe II (42), and the three-way joint III (73) is in communication with the outlet of the mixing pipe II (42) and the inlet of the mixing pipe III (43).

3. The apparatus according to claim 2, wherein: Spiral blades for disturbing fluid laminar flow are arranged in the mixing pipe (4), and the spiral blades are fixedly connected with the inner wall of the mixing pipe (4).

4. The continuous flow device for the preparation of carbon supported gold nanoparticle catalyst according to claim 2, wherein: A temperature sensor is arranged on the side wall of the mixing pipe (4).

5. The continuous flow device for the preparation of carbon supported gold nanoparticle catalyst according to claim 2, wherein: A flow meter (3) is further arranged between the peristaltic pump (2) and the mixing pipe (4), the inlet of the flow meter (3) is in communication with the outlet of the peristaltic pump (2), and the outlet of the flow meter (3) is in communication with the mixing pipe (4).

6. The continuous flow device for the preparation of carbon supported gold nanoparticle catalyst according to claim 1, wherein: The connecting pipe (6) for transmitting the reducing agent adopts a short pipe (621), the length of the short pipe (621) is smaller than that of the connecting pipes (6) for transmitting the other three raw material solution containers (1), and the inner diameter of the short pipe (621) is also smaller than that of the connecting pipes (6) for transmitting the other three raw material solution containers (1).

7. The apparatus according to claim 6, wherein the apparatus is characterized by: The peristaltic pump (2) is connected with the connecting pipes (6) for delivering the four raw material solutions, and the connecting pipes (6) are made of silica gel hose material.

8. The continuous flow device for the preparation of carbon supported gold nanoparticle catalyst according to claim 1, wherein: The peristaltic pump (2) is provided with damping members for reducing vibration during operation of the peristaltic pump (2).

9. The continuous flow device for the preparation of carbon supported gold nanoparticle catalyst according to claim 1, wherein: ​

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