Continuous production equipment and preparation method of ZnZrO2 catalyst

Abstract

The invention discloses continuous production equipment and a preparation method of a ZnZrO2 catalyst, and the continuous production equipment comprises a base which is used for stably supporting the whole equipment; the reaction tank is fixedly mounted on the base and serves as a main reaction place for catalyst preparation; the heating tank is arranged at the bottom in the reaction tank and is used for preheating the continuous phase solution; the continuous phase feeding hole is formed in the bottom of the reaction tank, penetrates through the heating tank and is used for introducing a continuous phase solution into the heating tank for heating; the dispersed phase feeding hole is formed in one side of the front end of the reaction tank, penetrates into the reaction tank and is used for introducing a dispersed phase solution into the reaction tank to be mixed with the heated continuous phase solution; the discharge hole is formed in one side of the rear end of the reaction tank, penetrates into the reaction tank and is used for discharging a reacted mixture; the gas inlet pipe is arranged at the rear end of the reaction tank and is used for introducing gas into the reaction tank to adjust the reaction environment.

Description

Technical Field

[0001] The invention relates to the technical field of chemical reaction devices, in particular to continuous production equipment and a preparation method of a ZnZrO2 catalyst. Background Art

[0002] In the chemical production process, the preparation and application of catalysts are key links to improve reaction efficiency and product selectivity. The nano-sizing degree and size uniformity of ZnZrO2 catalysts have a significant impact on their catalytic performance. Nanoscale catalysts have a larger specific surface area and can provide more effective catalytic active sites, thereby significantly improving the efficiency of catalytic reactions. In addition, nanocatalysts also exhibit unique surface effects and quantum size effects, which help optimize catalytic reaction pathways and improve product selectivity. The size uniformity of catalyst particles directly affects the stability of their catalytic performance. Catalyst particles with uniform size distribution can maintain consistent catalytic activity during the reaction and reduce fluctuations in catalytic efficiency caused by differences in particle size. At the same time, uniform size also helps to improve the bulk density and heat and mass transfer efficiency of the catalyst, further improving the overall performance of the reactor.

[0003] The existing ZnZrO2 production equipment mainly includes a raw material mixing system, a heat treatment system, and a grinding and screening system. The raw material mixing system is responsible for mixing the zinc source (such as zinc nitrate), the zirconium source (such as zirconium nitrate) and other additives in a certain proportion to form a precursor solution or a mixture. The existing preparation method is difficult to effectively control the degree of nano-sizing of the catalyst particles, resulting in the limitation of the specific surface area and the number of active sites of the catalyst, which affects the efficiency of the catalytic reaction. Although the grinding and screening process can improve the size distribution of the catalyst particles to a certain extent, it is difficult to achieve a high degree of uniformity. Catalyst particles of uneven size are prone to fluctuations in catalytic efficiency during the reaction, affecting the quality and stability of the product.

[0004] Therefore, it is necessary to provide a continuous production device and a preparation method of ZnZrO2 catalyst to solve the problems raised in the above background technology. Summary of the invention

[0005] To achieve the above object, the present invention provides the following technical solution: a continuous production device for ZnZrO2 catalyst, comprising:

[0006] The base is used to stably support the entire device;

[0007] A reaction tank, fixedly mounted on the base, serving as the main reaction site for catalyst preparation;

[0008] A heating tank, disposed at the bottom of the reaction tank, for preheating the continuous phase solution;

[0009] A continuous phase feed port is provided at the bottom of the reaction tank and is connected to the heating tank, and is used to introduce the continuous phase solution into the heating tank for heating;

[0010] The dispersed phase feed port is arranged at one side of the front end of the reaction tank and penetrates into the interior of the reaction tank, and is used to introduce the dispersed phase solution into the reaction tank and mix it with the heated continuous phase solution;

[0011] The discharge port is arranged at one side of the rear end of the reaction tank and penetrates into the interior of the reaction tank for discharging the mixture after the reaction;

[0012] The air inlet pipe is arranged at the rear end of the reaction tank and is used to introduce gas into the reaction tank to adjust the reaction environment.

[0013] Further, as a preference, two cylinders are distributed in the heating tank, a piston is slidably arranged in each cylinder, a screw is rotatably arranged in each cylinder, and the screw is threadedly connected to the piston;

[0014] Each of the cylinders is provided with a continuous phase output port connected to the reaction tank;

[0015] One end of the screw rod penetrates outside the reaction tank and is connected to a driving device.

[0016] Further, as a preference, a plurality of heating tubes are fixedly distributed in each of the cylinders, and the heating tubes slide through the piston.

[0017] Furthermore, as a preference, the continuous phase feed port, the dispersed phase feed port, the discharge port, and the continuous phase output port are all provided with a one-way valve consistent with the flow direction of the solution.

[0018] Furthermore, preferably, the threads of the two screws in the two cylinders have opposite rotation directions.

[0019] Furthermore, preferably, a plurality of partitions are distributed between the gap between the reaction tank and the heating tank, and notches are respectively provided at the diagonals of two adjacent partitions.

[0020] Furthermore, preferably, a partition at the front end is fixedly connected to the side walls of the reaction tank and the heating tank, and the remaining partitions are slidably arranged in the gap between the reaction tank and the heating tank, and spring sheets are distributed between two adjacent partitions.

[0021] Further, as a preference, a telescopic cylinder is provided at the rear end of the reaction tank, and a piston rod of the telescopic cylinder slides through the reaction tank and is fixed in a partition plate located at the rear end.

[0022] Further, as a preference, the air inlet pipe passes through between two circular tubes of the heating tank, a nozzle is embedded in the outer wall of the heating tank, and an outlet of the nozzle passes through the reaction tank.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] In the present invention, the heating tank in the device adopts a cylinder, a screw and a piston combination design, which realizes the continuous heating and supply of the continuous phase solution. The screw threads in the two cylinders rotate in opposite directions, ensuring that one cylinder is sucking the solution while the other cylinder is outputting the heated solution. This alternating working mode not only improves the heating efficiency, but also ensures the continuous and stable supply of the continuous phase solution. In addition, the arrangement of the heating pipe not only ensures the heating effect, but also limits the rotation of the piston, ensuring the stable operation of the system.

[0025] In the present invention, the multiple baffles between the reaction tank and the heating tank form a microchannel structure, which not only increases the flow path of the mixed solution, but also changes the space size of the microchannel by adjusting the spacing between the baffles, thereby achieving precise control of the reaction rate. This design helps to strengthen the chemical precipitation reaction process, promote the uniform generation of ZnZrO2 catalyst, and improve the nano-level degree and size uniformity of the product.

[0026] In the present invention, the air inlet pipe and its supporting nozzle enable the inert gas to be accurately sprayed into the reaction tank, and indirectly affect the reaction rate by changing the collision frequency and effective collision rate between the reactant molecules. Combined with the adjustment of the partition spacing, the reaction environment can be fully optimized to meet the needs under different reaction conditions. In addition, the introduction of inert gas can also effectively prevent the oxidation of reactants or products and protect the activity of the catalyst. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the structure of a continuous production device for ZnZrO2 catalyst;

[0028] Figure 2 It is a schematic diagram of the structure inside the reaction tank;

[0029] Figure 3 It is a schematic diagram of the structure inside the heating tank;

[0030] Figure 4 It is a structural schematic diagram of the vertical section of the reaction tank;

[0031] Figure 5 It is a structural schematic diagram of the cross section of the reaction tank;

[0032] In the figure: 1. base; 2. reaction tank; 21. heating tank; 22. cylinder; 23. partition; 24. piston; 25. screw; 26. heating tube; 27. notch; 28. spring sheet; 3. continuous phase feed port; 4. dispersed phase feed port; 5. discharge port; 6. air inlet pipe; 61. nozzle; 7. driving device; 8. telescopic cylinder; 9. continuous phase output port. DETAILED DESCRIPTION

[0033] See also Figure 1 to Figure 5 In an embodiment of the present invention, a continuous production device for ZnZrO2 catalyst comprises:

[0034] Base 1, used to stably support the entire device;

[0035] A reaction tank 2, fixedly mounted on the base 1, serves as the main reaction site for catalyst preparation;

[0036] A heating tank 21 is disposed at the bottom of the reaction tank 2 and is used to preheat the continuous phase solution;

[0037] A continuous phase feed port 3 is provided at the bottom of the reaction tank 2 and is connected to the heating tank 21, and is used to introduce the continuous phase solution into the heating tank 21 for heating;

[0038] The dispersed phase feed port 4 is arranged at one side of the front end of the reaction tank 2 and penetrates into the interior of the reaction tank 2, and is used to introduce the dispersed phase solution into the reaction tank 2 and mix it with the heated continuous phase solution;

[0039] The discharge port 5 is arranged at one side of the rear end of the reaction tank 2 and penetrates into the interior of the reaction tank 2 for discharging the mixture after the reaction;

[0040] The air inlet pipe 6 is arranged at the rear end of the reaction tank 2 and is used to introduce gas into the reaction tank 2 to adjust the reaction environment.

[0041] The continuous phase solution enters the heating tank 21 from the continuous phase feed port 3, is heated in the heating tank 21, and is output to the reaction tank 2, where it is mixed with the dispersed phase solution entering the reaction tank 2 from the dispersed phase feed port 4, reacts, and is output from the discharge port 5.

[0042] In this embodiment, two cylinders 22 are distributed in the heating tank 21, a piston 24 is slidably disposed in each cylinder 22, and a screw 25 is rotatably disposed in each cylinder 22, and the screw 25 is threadedly connected to the piston 24;

[0043] Each of the cylinders 22 is provided with a continuous phase outlet 9 connected to the reaction tank 2;

[0044] One end of the screw rod 25 passes through the outside of the reaction tank 2 and is connected to the driving device 7 .

[0045] In this embodiment, a plurality of heating tubes 26 are fixedly distributed in each of the cylinders 22, and the heating tubes 26 slide through the piston 24, so that the heating tubes 26 can be used to heat the continuous phase solution and limit the rotation of the piston 24, ensuring that the piston 24 can be driven to slide when the screw 25 rotates, thereby sucking the continuous phase solution from the continuous phase feed port 3 into the cylinder 22 for heating and outputting it into the reaction tank 2.

[0046] In this embodiment, the continuous phase feed port 3, the dispersed phase feed port 4, the discharge port 5, and the continuous phase output port 9 are all provided with one-way valves that are consistent with the flow direction of the solution.

[0047] In this embodiment, the threads of the two screws 25 in the two cylinders 22 are rotated in opposite directions, so that when the two screws 25 rotate synchronously, the piston 24 in one cylinder 22 sucks the continuous phase into the cylinder 22 from the continuous phase feed port 3, and the piston 24 in the other cylinder 22 outputs the heated continuous phase solution into the reaction tank 2 from the continuous phase output port 9, so that when one cylinder 22 absorbs the solution, the other cylinder 22 outputs the solution, and the two operations are performed alternately, ensuring that the heated solution can be continuously supplied, improving work efficiency, and ensuring that the solution has sufficient heating time in the cylinder 22.

[0048] In this embodiment, a plurality of partitions 23 are distributed between the gap between the reaction tank 2 and the heating tank 21, and notches 27 are respectively provided at the diagonals of two adjacent partitions 23. The partitions 23 enable the mixed solution to flow along the gaps between the partitions 23 to increase the flow path, thereby achieving microchannel process enhancement of the chemical precipitation reaction.

[0049] In this embodiment, a partition plate 23 at the front end is fixedly connected to the side wall of the reaction tank 2 and the heating tank 21, and the remaining partition plates 23 are slidably arranged in the gap between the reaction tank 2 and the heating tank 21. A spring sheet 28 is distributed between two adjacent partition plates 23. A telescopic cylinder 8 is arranged at the rear end of the reaction tank 2. The piston rod of the telescopic cylinder 8 slides through the reaction tank 2 and is fixedly placed in a partition plate 23 at the rear end. That is to say, the position of the partition plate 23 at the rear end can be changed by the telescopic cylinder 8. Under the action of the spring sheet 28, each partition plate 23 quotes a uniform spacing, thereby changing the spacing between each partition plate 23 to change the space size of the microchannel, thereby adjusting different reaction rates according to the situation. Specifically, for example, when the concentration of the reactant is high, the reaction rate is usually faster, which may cause the sediment particles to grow and aggregate rapidly to form larger particles. In order to control the particle size, the microchannel space can be reduced by reducing the partition spacing, slowing down the reaction rate, and limiting its growth space to prevent the particles from being too large or agglomerated. On the contrary, for reaction conditions with slower growth rates, the partition spacing can be appropriately increased to increase particle growth production efficiency.

[0050] In this embodiment, the air inlet pipe 6 penetrates between the two round tubes 22 of the heating tank 21, and the outer wall of the heating tank 21 is embedded with a nozzle 61, and the outlet of the nozzle 61 penetrates into the reaction tank 2. That is to say, the gas can be sprayed into the reaction tank 2 by injecting an inert gas into the air inlet pipe 6. Inertness indirectly affects the reaction rate by changing the collision frequency and effective collision rate between the reactant molecules. Specifically, according to the Le Chatelier principle, increasing the concentration of the inert gas will make the reaction system tend to reduce the total number of molecules to maintain equilibrium. Therefore, for reactions in which the volume is reduced after the reaction, the injection of inert gas may move the equilibrium in the reverse reaction direction; while for reactions in which the volume is increased after the reaction, the equilibrium may be moved in the forward reaction direction. Therefore, by adjusting the amount of inert gas injected and the spacing between the partitions 23, the reaction temperature, the concentration and proportion of the solution and other parameters, the controllable growth of the grains is achieved, and the target product size is uniform and the degree of nano-ization is high.

[0051] A method for preparing a catalyst for continuous production, comprising:

[0052] S1. Prepare (NH4)2CO3 solution as a continuous phase solution and store it in a liquid storage tank, mix and dissolve Zn(NO3)2·6H2O and Zr(NO3)4·5H2O in a predetermined ratio to obtain a dispersed phase solution, and store it in another liquid storage tank;

[0053] S2, passing the (NH4)2CO3 solution into the heating tank 21 through the continuous phase feed port 3, and preheating the solution in the heating tank 21; passing the uniformly mixed Zn(NO3)2·6H2O and Zr(NO3)4·5H2O solution into the reaction tank 2 through the dispersed phase feed port 4;

[0054] S3, the (NH4)2CO3 solution preheated by the heating tank 21 enters the reaction tank 2, mixes with the dispersed phase solution and undergoes a chemical precipitation reaction. At the same time, the air inlet pipe 6 introduces an appropriate amount of nitrogen into the reaction tank 2, and the appropriate pressure in the reaction tank is maintained by adjusting the air intake;

[0055] S4, real-time monitoring of the temperature, pressure and other parameters in the reaction tank, and adjusting the heating and air intake according to the preset program to ensure that the reaction is carried out under optimal conditions;

[0056] S5. In the reaction tank 2, (NH4)2CO3 in the mixed solution reacts with Zn(NO3)2·6H2O and Zr(NO3)4·5H2O to generate a precipitate of zinc-zirconium mixed oxide;

[0057] S6, the zinc-zirconium mixed oxide precipitate generated by the reaction is continuously discharged from the discharge port 5 along with the solution, and is collected by a subsequent collecting device;

[0058] S7. Place the collected zinc-zirconium mixed oxide in a calcining furnace and calcine it at 500° C. for 3 hours to convert it into a ZnZrO2 catalyst.

[0059] What is described above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A continuous production device for ZnZrO2 catalyst, characterized in that: include A base (1), used to stably support the entire device; A reaction tank (2) is fixedly mounted on the base (1) and serves as a main reaction site for catalyst preparation; A heating tank (21), arranged at the bottom of the reaction tank (2), for preheating the continuous phase solution; A continuous phase feed port (3) is provided at the bottom of the reaction tank (2) and is connected to the heating tank (21), and is used to introduce the continuous phase solution into the heating tank (21) for heating; A dispersed phase feed port (4) is arranged at one side of the front end of the reaction tank (2) and penetrates into the interior of the reaction tank (2) for introducing the dispersed phase solution into the reaction tank (2) and mixing it with the heated continuous phase solution; A discharge port (5) is arranged at one side of the rear end of the reaction tank (2) and penetrates into the interior of the reaction tank (2) for discharging the mixture after the reaction; An air inlet pipe (6) is arranged at the rear end of the reaction tank (2) and is used to introduce gas into the reaction tank (2) to adjust the reaction environment.

2. The continuous production equipment of ZnZrO2 catalyst according to claim 1, characterized in that: Two cylinders (22) are distributed in the heating tank (21), a piston (24) is slidably arranged in each cylinder (22), a screw (25) is rotatably arranged in each cylinder (22), and the screw (25) is threadedly connected to the piston (24); Each of the cylinders (22) is provided with a continuous phase output port (9) connected to the reaction tank (2); One end of the screw (25) passes through the outside of the reaction tank (2) and is connected to the driving device (7).

3. The continuous production equipment of ZnZrO2 catalyst according to claim 2, characterized in that: A plurality of heating tubes (26) are fixedly distributed in each cylinder (22), and the heating tubes (26) slide through the piston (24).

4. The continuous production equipment of ZnZrO2 catalyst according to claim 2, characterized in that: The continuous phase feed port (3), the dispersed phase feed port (4), the discharge port (5), and the continuous phase output port (9) are all provided with one-way valves that are consistent with the flow direction of the solution.

5. The continuous production equipment of ZnZrO2 catalyst according to claim 2, characterized in that: The threads of the two screws (25) in the two cylinders (22) are in opposite directions.

6. The continuous production equipment of ZnZrO2 catalyst according to claim 1, characterized in that: A plurality of partitions (23) are distributed between the reaction tank (2) and the heating tank (21), and notches (27) are respectively provided at the diagonal positions of two adjacent partitions (23).

7. The continuous production equipment of ZnZrO2 catalyst according to claim 6, characterized in that: A partition plate (23) at the front end is fixedly connected to the side walls of the reaction tank (2) and the heating tank (21), and the remaining partition plates (23) are slidably arranged in the gap between the reaction tank (2) and the heating tank (21), and a spring sheet (28) is distributed between two adjacent partition plates (23).

8. The continuous production equipment of ZnZrO2 catalyst according to claim 1, characterized in that: A telescopic cylinder (8) is provided at the rear end of the reaction tank (2), and a piston rod of the telescopic cylinder (8) slides through the reaction tank (2) and is fixed in a partition plate (23) located at the rear end.

9. The continuous production equipment of ZnZrO2 catalyst according to claim 1, characterized in that: The air inlet pipe (6) penetrates between the two circular tubes (22) of the heating tank (21); a nozzle (61) is embedded in the outer wall of the heating tank (21); and the outlet of the nozzle (61) penetrates into the reaction tank (2).

10. A method for preparing a continuous production of a ZnZrO2 catalyst, using the continuous production equipment for a ZnZrO2 catalyst according to claim 1, characterized in that: include: S1. Prepare (NH4)2CO3 solution as a continuous phase solution and store it in a liquid storage tank, mix and dissolve Zn(NO3)2·6H2O and Zr(NO3)4·5H2O in a predetermined ratio to obtain a dispersed phase solution, and store it in another liquid storage tank; S2, passing the (NH4)2CO3 solution into the heating tank (21) through the continuous phase feed port (3), and preheating the solution in the heating tank (21); passing the uniformly mixed Zn(NO3)2·6H2O and Zr(NO3)4·5H2O solution into the reaction tank (2) through the dispersed phase feed port (4); S3, the (NH4)2CO3 solution preheated by the heating tank (21) enters the reaction tank (2), mixes with the dispersed phase solution and undergoes a chemical precipitation reaction. At the same time, an appropriate amount of nitrogen is introduced into the reaction tank (2) through the air inlet pipe (6) to prevent the occurrence of an oxidation reaction, and an appropriate pressure in the reaction tank is maintained by adjusting the air intake amount; S4, real-time monitoring of the temperature, pressure and other parameters in the reaction tank, and adjusting the heating and air intake according to the preset program to ensure that the reaction is carried out under optimal conditions; S5. In the reaction tank (2), (NH4)2CO3 in the mixed solution reacts with Zn(NO3)2·6H2O and Zr(NO3)4·5H2O to generate a precipitate of zinc-zirconium mixed oxide; S6, the zinc-zirconium mixed oxide precipitate generated by the reaction is continuously discharged from the discharge port (5) along with the solution, and is collected by a subsequent collecting device; S7. Place the collected zinc-zirconium mixed oxide in a calcining furnace and calcine it at 500° C. for 3 hours to convert it into a ZnZrO2 catalyst.

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