Evaluation device for cyclohexane dehydrogenation benzene preparation catalyst

Abstract

The utility model discloses an evaluation device for a cyclohexane dehydrogenation benzene preparation catalyst. The evaluation device comprises a feeding unit, a vaporization unit, a dehydrogenation reaction unit, a product analysis unit and a product condensation and recovery unit, the feeding unit is communicated with the vaporization unit through a pipeline; the vaporization units are communicated through pipelines; the product analysis unit is communicated with the dehydrogenation reaction unit through a pipeline; the product condensation recovery unit is communicated with the product analysis unit through a pipeline; the dehydrogenation reaction unit comprises: a partial pressure valve; and the partial pressure valve is arranged on a pipeline for communicating the dehydrogenation reaction unit with the product analysis unit. The hydrogen source, the nitrogen source and the raw material tank are respectively communicated with a dehydrogenation reactor pipeline through pipeline arrangement, a reaction is carried out after a corresponding catalyst is placed in the dehydrogenation reactor according to test requirements, and an outlet of the dehydrogenation reactor is communicated with a gas chromatograph through a six-way valve arranged on the pipeline. The effective detection on the catalytic performance of various catalysts is realized.

Description

Technical Field

[0001] This application relates to the technical field of alkane dehydrogenation, and particularly to an evaluation device for a cyclohexane dehydrogenation to benzene catalyst. Background Art

[0002] The existing sources of cyclohexane can be by-products generated during the preparation of cyclohexanone in the water hydration method of benzene-based caprolactam production. Currently, about 800,000 tons of cyclohexane are by-produced in China every year. How to make full use of the by-product cyclohexane has always been a major problem in the caprolactam industry. Existing research has found that cyclohexane dehydrogenation to benzene can be an effective means to increase the added value of cyclohexane by-products.

[0003] Patents CN 106588536 A and CN112892613A disclose a method for efficiently utilizing raw material benzene by using cyclohexane dehydrogenation technology during the production of cyclohexanone. The reaction system of this method is four reactors in series, with a large cyclohexane treatment capacity, and high-efficiency dehydrogenation of cyclohexane is achieved at relatively high reaction temperatures and pressures; Patent CN218741894 U provides a production system for low-pressure cyclohexane dehydrogenation to benzene. This system uses a shell-and-tube reactor, which can achieve high-efficiency and high-stability dehydrogenation of cyclohexane to benzene under low-pressure conditions, and can also recover as much heat as possible from the reaction materials. The above process methods can recycle the benzene and hydrogen generated by cyclohexane dehydrogenation to the benzene hydrogenation system as raw materials to participate in the reaction, realizing the closed-loop cycle of raw materials and products in the production process of the cyclohexanone device, and is an environmentally friendly green chemical production process with good development prospects.

[0004] Patent CN 115445612 A discloses a dehydrogenation catalyst, its preparation method and application, and a method for cyclohexane dehydrogenation to benzene ring. In this method, the Pt-supported catalyst undergoes cyclohexane dehydrogenation to benzene ring reaction in a simulated isothermal shell-and-tube reactor and an adiabatic fixed-bed reactor, with high activity and stability.

[0005] Currently reported cyclohexane dehydrogenation methods all use fixed-bed reactors. During the reaction process, the products need to be condensed and manually sampled for analysis. The operation is cumbersome, and the pressure in the reactor is likely to fluctuate during the sampling process, affecting the stability of the dehydrogenation reaction process, resulting in inaccurate evaluation of the dehydrogenation performance of the catalyst.

[0006] The cyclohexane dehydrogenation catalyst is the core of the dehydrogenation technology. The performance of the dehydrogenation catalyst directly determines the operation efficiency of the industrial device. To evaluate the performance of the cyclohexane dehydrogenation catalyst, a reaction needs to be carried out in a simulated reactor and sampling is required during the reaction. However, the existing sampling process is prone to cause pressure changes, affecting the accuracy of the simulation results, and there is a lack of an effective simulation sampling device.

[0007] The information disclosed in the background section is only intended to enhance the overall understanding of the background of the present utility model and should not be regarded as an admission or any form of implication that such information constitutes the prior art already known to those of ordinary skill in the art. Summary of the Utility Model

[0008] The present application provides an evaluation device for a cyclohexane dehydrogenation to benzene catalyst. This system can simulate different operating conditions, is simple to operate, has stable control, and can accurately evaluate the dehydrogenation performance of the catalyst, which has good guiding value for laboratory research and product performance inspection of dehydrogenation catalysts.

[0009] The present application provides an evaluation device for a cyclohexane dehydrogenation to benzene catalyst, including: a feed unit, a vaporization unit, a dehydrogenation reaction unit, a product analysis unit, and a product condensation and recovery unit;

[0010] The feed unit and the vaporization unit are connected by pipelines; the product analysis unit and the dehydrogenation reaction unit are connected by pipelines; the product condensation and recovery unit and the product analysis unit are connected by pipelines;

[0011] The dehydrogenation reaction unit includes: a pressure regulating valve; the pressure regulating valve is arranged on the pipeline connecting the dehydrogenation reaction unit and the product analysis unit.

[0012] Preferably, the product analysis unit includes: a six-way valve and a gas chromatograph; the dehydrogenation reaction unit is connected to the gas chromatograph through the six-way valve.

[0013] Preferably, the dehydrogenation reaction unit includes: a dehydrogenation reactor, a plurality of three-way control valves, and a heating tape; a three-way control valve is arranged on the inlet pipeline of the dehydrogenation reactor; on the outlet pipeline of the dehydrogenation reactor; a heating tape is arranged on the inlet pipeline of the dehydrogenation reactor;

[0014] A heating tape is arranged on the outlet pipeline of the dehydrogenation reactor.

[0015] Preferably, the dehydrogenation reaction unit includes: a multi-stage dehydrogenation reactor; the upper-stage dehydrogenation reactor and the lower-stage dehydrogenation reactor are connected in parallel and are connected to the product analysis unit by pipelines; each stage of dehydrogenation reactor is respectively connected to the product analysis unit by pipelines.

[0016] Preferably, the vaporization unit includes: a filter and a vaporizer; the filter and the vaporizer are arranged at intervals on the pipeline connecting the feed unit and the dehydrogenation reaction unit.

[0017] Preferably, the feed unit includes: a hydrogen source pipe group, a nitrogen source pipe group, and a raw material tank pipe group; the hydrogen source pipe group, the nitrogen source pipe group, and the raw material tank pipe group are respectively connected to the dehydrogenation reaction unit through the vaporization unit pipeline.

[0018] Preferably, the hydrogen source pipe group includes: a hydrogen source, a branch control valve, a gas mass flow meter, a check valve, and a gas pressure reducing valve; the branch control valve, the gas mass flow meter, the check valve, and the gas pressure reducing valve are arranged at intervals on the pipeline connecting the hydrogen source and the vaporization unit;

[0019] Preferably, the hydrogen source pipe group includes: a hydrogen source, a plurality of branch pipes, and a main pipe; the hydrogen source is connected to the main pipe, and the main pipe is respectively connected to the dehydrogenation reaction unit pipeline through the branch pipes; the branch control valve, the gas mass flow meter, and the check valve are arranged at intervals on the branch pipes.

[0020] Preferably, the nitrogen source pipe group includes: a nitrogen source, a branch control valve, a gas mass flow meter, a check valve, and a gas pressure reducing valve; the branch control valve, the gas mass flow meter, the check valve, and the gas pressure reducing valve are arranged at intervals on the pipeline connecting the nitrogen source and the vaporization unit;

[0021] Preferably, the nitrogen source pipe group includes: a nitrogen source, a plurality of branch pipes, and a main pipe; the hydrogen source is connected to the main pipe, and the main pipe is respectively connected to the dehydrogenation reaction unit pipeline through the branch pipes; the branch control valve, the gas mass flow meter, and the check valve are arranged at intervals on the branch pipes.

[0022] Preferably, the raw material tank pipe group includes: a raw material tank, a branch control valve, a raw material infusion pump, and a check valve; the branch control valve, the raw material infusion pump, and the check valve are arranged at intervals on the pipeline connecting the raw material tank and the vaporization unit;

[0023] Preferably, the raw material tank pipe group includes: a raw material tank, a plurality of branch pipes, and a main pipe; the hydrogen source is connected to the main pipe, and the main pipe is respectively connected to the dehydrogenation reaction unit pipeline through the branch pipes; the branch control valve, the raw material infusion pump, and the check valve are arranged at intervals on the branch pipes.

[0024] Preferably, the product condensation recovery unit includes: a gas-liquid separator and a product collection tank;

[0025] The gas-liquid separator is connected to the outlet of the gas chromatograph through a six-way valve; the gas-liquid separator is connected to the product collection tank through a pipeline; a second tail gas exhaust pipeline is arranged at the gas outlet of the gas-liquid separator;

[0026] Preferably, it includes: a circulating cooling belt; the circulating cooling belt is arranged on the pipeline connecting the gas-liquid separator and the six-way valve; the circulating cooling belt is wrapped on the outer wall of the gas-liquid separator;

[0027] Preferably, it includes: a multi-stage dehydrogenation reaction unit, a multi-stage product analysis unit, and a multi-stage product condensation recovery unit; the multi-stage dehydrogenation reaction units and the multi-stage product analysis units are connected through pipelines; the multi-stage product condensation recovery units and the multi-stage product analysis units are connected through pipelines.

[0028] The beneficial effects that this application can produce include:

[0029] 1) The cyclohexane dehydrogenation to benzene catalyst evaluation device provided by this application realizes the connection of the hydrogen source, nitrogen source, and raw material tank to the dehydrogenation reactor pipeline through pipeline settings. After placing the corresponding catalyst in the dehydrogenation reactor according to the test requirements, the reaction is carried out. The outlet of the dehydrogenation reactor is connected to the gas chromatograph through a six-way valve arranged on the pipeline, realizing the effective detection of the catalytic performance of various catalysts.

[0030] 2) The cyclohexane dehydrogenation to benzene catalyst evaluation device provided by this application can avoid the change of the internal air pressure of the dehydrogenation reactor during sampling by setting a pressure dividing valve on the pipeline connecting the dehydrogenation reactor and the gas chromatograph, thereby improving the accuracy of the catalyst detection results.

[0031] 3) In the cyclohexane dehydrogenation to benzene catalyst evaluation device provided by this application, after the gas generated by the dehydrogenation reactor flows along the pipeline to the six-way valve, the operator can control the six-way valve regularly to realize the on-line detection of the gas, and can evaluate the dehydrogenation performance of the catalyst in real time and accurately, which has good guiding value for the laboratory research and product performance inspection of dehydrogenation catalysts. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the cyclohexane dehydrogenation to benzene catalyst evaluation device in at least one embodiment provided by this application;

[0033] Legend:

[0034] Hydrogen source 1, nitrogen source 2, raw material tank 3, infusion pump 4, pressure reducing valve 26, first gas transmission pipeline 20, second gas transmission pipeline 21, infusion pipeline 22, branch control valve 5, gas mass flowmeter 6, check valve 7, branch pipeline 23, filter 8, vaporizer 9, third gas transmission pipeline 27, heating tape 10, three-way control valve 18, dehydrogenation reactor 11, pressure dividing valve 12, fifth gas transmission pipeline 24, fourth gas transmission pipeline 28, six-way valve 13, gas chromatograph 14, first tail gas exhaust pipeline 29, circulating cooling tape 17, second tail gas exhaust pipeline 25, gas-liquid separator 15, product collection tank 16, product discharge control valve 30, constant temperature box. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the present utility model. Obviously, the described embodiments are some, but not all, of the embodiments of the present utility model. The components of the embodiments of the present utility model described and illustrated herein can be arranged and designed in various different configurations.

[0036] Accordingly, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected 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 scope of protection of the present invention.

[0037] Technical means not detailed in this application and not used to solve the technical problems of this application are set according to common general knowledge in the art, and multiple ways of setting common general knowledge can be realized.

[0038] See Figure 1 , the cyclohexane dehydrogenation to benzene catalyst evaluation device provided by this application includes: a feeding unit, a vaporization unit, a dehydrogenation reaction unit, a product analysis unit and a product condensation and recovery unit. The feeding unit and the vaporization unit are connected by pipelines; the dehydrogenation reaction unit and the vaporization unit are connected by pipelines; the product analysis unit and the dehydrogenation reaction unit are connected by pipelines; the product condensation and recovery unit and the product analysis unit are connected by pipelines.

[0039] In a specific embodiment, the feeding unit includes: a hydrogen source 1, a nitrogen source 2, a filter 8 and a vaporizer 9; an outlet of the hydrogen source 1 is connected with a gas transmission pipeline 20, an outlet of the nitrogen source 2 is connected with a gas transmission pipeline 21, a gas pressure reducing valve 26 is arranged on each gas transmission pipeline and is divided into multiple parallel branch pipelines 23, and a branch control valve 5, a gas mass flowmeter 6 and a check valve 7 are arranged on each branch pipeline 23. The other ends of the branch pipelines 23 are respectively connected with the dehydrogenation reaction unit by pipelines, and a filter 8 and a vaporizer 9 are arranged at intervals on the connected pipelines. The extended end of the gas transmission pipeline 21 is connected with the branch pipeline 23, and a branch control valve 5, a gas mass flowmeter 6 and a check valve 7 are arranged at intervals on the branch pipeline 23. After the gas transmission pipeline 21 is connected with the external connection pipe of the hydrogen source 1 through the branch pipeline 23 and then connected with the dehydrogenation reaction unit by pipelines, a filter 8 and a vaporizer 9 are arranged at intervals on the external connection pipe. The branch control valve 5 controls the introduction or cut-off of gas or raw materials, and the gas mass controller 6 controls the gas flow rate.

[0040] In a specific embodiment, the feeding unit includes: a raw material tank 3; an outlet of the raw material tank 3 is connected with an infusion pipeline 22, and the other end of the infusion pipeline 22 is respectively connected with multiple parallel branch pipelines 23, and a branch control valve 5, an infusion pump 6 and a check valve 7 are arranged at intervals on each branch pipeline to separately control the flow rates of the gas and cyclohexane liquid required for the reaction and prevent the test gas from flowing back. The infusion pipeline 22 on the raw material tank 3 is connected with the external connection pipeline of the branch pipeline 23 of the hydrogen source 1, and a filter 8 and a vaporizer 9 are arranged at intervals on the external connection pipe. The external connection pipe is connected with the dehydrogenation reaction unit by pipelines.

[0041] The hydrogen source 1, nitrogen source 2, and raw material tank 3 are connected to the filter 8 through the corresponding branch pipelines 23. After gas-liquid mixing and purification by the filter 8, they are connected to the vaporizer 9. The outlet end of the vaporizer 9 is connected to the gas transmission pipeline 27, and the gas transmission pipeline 27 is wrapped with a heating tape 10 to ensure the vaporization of the cyclohexane raw material. The heating tape 10 can ensure the vaporization of the raw material in the third gas transmission pipeline 27 to ensure the transportation state of the raw material gas.

[0042] In a specific embodiment, the dehydrogenation reaction unit includes: a dehydrogenation reactor 11, a pressure regulator 12, and a plurality of three-way control valves 18. The dehydrogenation reactors 11 are arranged in pairs. The inlet of the first dehydrogenation reactor is connected to the pipeline of the feeding unit; the inlet of the second dehydrogenation reactor is connected to the pipeline of the feeding unit and the outlet pipeline of the first dehydrogenation reactor. Three-way control valves 18 are provided on both the inlet and outlet pipelines of the dehydrogenation reactor 11; the outlet of the dehydrogenation reactor 11 is connected to the inlet pipeline of the pressure regulator 12; the outlet of the pressure regulator 12 is connected to the pipeline of the product analysis unit. The pressure in the reactor 11 is controlled by the pressure dividing valve 12. By setting the pressure dividing valve 12, the pressure in the reactor can be effectively controlled. The pressure in the pipeline where the pressure dividing valve (12) is connected to the dehydrogenation reaction unit is constant, and the pressure in the pipeline where the pressure dividing valve (12) is connected to the product analysis unit is normal pressure, avoiding pressure fluctuations during sampling.

[0043] In a specific embodiment, the dehydrogenation reactor 11 is connected to the pipeline of the product analysis unit through the outlet pipeline 28. A pressure regulator 12 is provided on the outlet pipeline 28 to regulate the reaction pressure. By controlling the valve core of the three-way control valve 18, the reaction product can be collected to the pressure regulator 12 through the gas transmission pipeline 28, or the reaction product can be collected to the next-stage dehydrogenation reactor 11 through the gas transmission pipeline 24 and then collected to the product analysis unit through the gas transmission pipeline 28.

[0044] Only with the dehydrogenation reaction unit of the above structure can each reactor 11 independently react to the feed to separately evaluate the test conditions in each reactor, or a comprehensive evaluation test of the internal reaction of multiple reactors in series can be carried out by controlling the three-way control valve 18 to connect the reactors at all levels.

[0045] In a specific embodiment, the gas transmission pipeline 28 is coated with a heating tape 10 to ensure the full vaporization of the reaction product for easy analysis. The heating tape 10 can ensure the vaporization of the product in the fourth gas transmission pipeline 28 and the fifth gas transmission pipeline 24 to ensure the on-line sampling analysis of the gas chromatograph 14.

[0046] In a specific embodiment, the product analysis unit includes: a six-way valve 13 and a gas chromatograph 14. The product obtained from the reaction of the dehydrogenation reaction unit is connected to the six-way valve 13 through the gas transmission pipeline 28. The six-way valve 13 is placed in the constant temperature box of the gas chromatograph 14, and the product gas enters the detection chamber of the gas chromatograph 14 through the six-way valve 13 for product sampling analysis.

[0047] In a specific embodiment, six-way valves 13 are arranged in pairs in the gas chromatograph 14 to control the feeding of each analysis sample chamber in the gas chromatograph 14. The tail gas outlet ends of the six-way valves 13 are connected to a tail gas exhaust pipe 29 and are communicated with the product condensation recovery unit through the tail gas exhaust pipe 29.

[0048] In a specific embodiment, the product condensation recovery unit includes: a gas-liquid separator 15, a product collection tank 16 and a constant temperature box. The tail gas outlet of the six-way valve 13 is connected to the gas-liquid separator 15 through the tail gas exhaust pipe 29. The gas phase outlet of the gas-liquid separator 15 is connected to a tail gas exhaust pipe 25, and the liquid phase outlet of the gas-liquid separator 15 is connected to the product collection tank 16.

[0049] During testing:

[0050] A catalyst for dehydrogenating cyclohexane to benzene is added into the dehydrogenation reactor 11. Hydrogen, nitrogen and the raw material are gathered at the filter 8 on the external connecting pipe through the feeding unit. The raw material is vaporized after being filtered to remove impurities through the vaporizer 9, and the vaporized raw material mixture is introduced into the dehydrogenation reactor 11 through the third gas transmission pipe 27 to participate in the reaction. By switching the valve core of the three-way control valve 18, each reactor 11 reacts independently.

[0051] The product obtained from the reaction of the dehydrogenation reaction unit enters the gas chromatograph 14 through the six-way valve 13 via the fourth gas transmission pipe 28. The gas chromatograph 14 and the six-way valve 13 are linked to achieve on-line sampling and analysis.

[0052] The tail gas of the six-way valve 13 is introduced into the gas-liquid separator 15 through the first tail gas exhaust pipe 29 for gas-liquid separation. The separated gas phase is discharged through the second tail gas exhaust pipe 25, and the separated liquid phase is introduced into the product collection tank 16. By controlling the product discharge control valve 30 arranged at the outlet of the product collection tank 16, the liquid product can be discharged.

[0053] In a specific embodiment, it includes: a circulating cooling belt 17; the tail gas exhaust pipe 29 and the gas-liquid separator 15 are wrapped with the circulating cooling belt 17. The water in the constant temperature box is communicated with the inlet and outlet pipe of the circulating cooling belt 17 through a circulating pipeline to realize the circulating heat exchange of the circulating cooling belt 17, so that the gaseous products in the tail gas exhaust pipe 29 and the gas-liquid separator 15 are condensed. To ensure that the organic matter in the reaction product is condensed into a liquid and flows into the product collection tank 16, and the separated nitrogen or hydrogen is discharged through the second tail gas exhaust pipe 25.

[0054] In a specific embodiment, pressure reducing valves 26 are arranged on both the first gas transmission pipe 20 and the first gas transmission pipe 21. The total pressure of the inlet gas is controlled through the pressure reducing valve 26.

[0055] In a specific embodiment, the infusion pipeline 22 is separately connected to the branch pipeline 23, and each branch pipeline 23 is provided with a branch control valve 5, a raw material infusion pump 4, and a check valve 7. The raw material infusion pump 4 controls the flow rate of the raw material liquid, and the check valve 7 prevents the raw material gas-liquid from flowing back.

[0056] In a specific embodiment, the first gas transmission pipeline 20, the second gas transmission pipeline 21, the infusion pipeline 22, the third gas transmission pipeline 27, the fourth gas transmission pipeline 28, and the fifth gas transmission pipeline 24 can be pressure-resistant stainless steel pipelines.

[0057] In some embodiments, in combination Figure 1 As shown, the reactors 11 can also be connected in series by switching the spool of the three-way control valve 18. The reaction product enters the next reactor 11 through the fifth gas transmission pipeline 24, and then passes through the fourth gas transmission pipeline 28 into the six-way valve 13 in the gas chromatograph 14 for sampling and testing analysis.

[0058] In a specific embodiment, the spool of the three-way control valve 18 is a corrosion-resistant spool, the valve body of the six-way valve 13 is placed in the thermostat of the gas chromatograph 14, and the spool of the six-way valve 13 is a corrosion-resistant spool.

[0059] In a specific embodiment, the first tail gas exhaust pipe 29 and the second tail gas exhaust pipe 25 can be stainless steel pipes, and the liquid product can be discharged through the product discharge control valve 30.

[0060] In a specific embodiment, the usage process of the cyclohexane dehydrogenation to benzene catalyst evaluation system of the embodiment of the present utility model is as follows: Load the cyclohexane dehydrogenation to benzene catalyst into the dehydrogenation reactor 11. Open the branch control valve 5 on the second gas transmission pipeline 21, set the nitrogen gas flow rate according to the specific usage requirements, adjust the pressure reducing valve 12 to make the pressure in the reactor 11 normal pressure, and control the spool of the three-way control valve 18 to make the reactors 11 independent of each other. Open the vaporizer 9 and control the temperature of the vaporizer 9 at 100 - 150 °C. Open the heating tape 10 and control the temperature of the heating tape 10 at 100 - 150 °C. Open the heating furnace temperature control of the dehydrogenation reactor 11 and raise the reactor temperature to 300 °C, and keep it at this temperature for 30 min to remove the moisture in the catalyst.

[0061] Close the branch control valve 5 on the second gas transmission pipeline 21, open the branch control valve 5 on the first gas transmission pipeline 20, and introduce hydrogen according to the specific usage requirements by setting the gas flow rate, and purge for 30 min to remove nitrogen. Open the branch control valve 5 of the infusion pipeline 22 and set the raw material liquid flow rate according to the specific usage requirements.

[0062] Open the incubator and circulate the cooling water. Set the temperature of the cooling water at 2 - 5°C. Control the reaction temperature of the dehydrogenation reactor 11 between 300 - 450°C. According to specific usage requirements, after heating up to the target reaction temperature point, stay at each temperature point for 12 h. Adjust the pressure regulating valve 18 to control the reaction pressure between 0 - 500 Kpa. Set the reaction pressure according to specific usage requirements and stay at each pressure point for 8 h.

[0063] When detection is required, first open the pressure regulating valve 12 to achieve stable pressure sampling. Then close the pressure regulating valve 12. The sample enters the connecting pipeline. This part of the sample to be detected enters the gas chromatograph 14 through the pipeline via the six-way valve 13 with the opening of the corresponding outlet of the six-way valve 13, realizing automatic sampling and testing analysis once every 1 h, and achieving automatic sampling and on-line evaluation of the dehydrogenation performance of the catalyst.

[0064] Although the present utility model has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacement on some of the technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. An evaluation device for a catalyst for dehydrogenating cyclohexane to benzene, characterized in that, Comprising: A feed unit, a vaporization unit, a dehydrogenation reaction unit, a product analysis unit, and a product condensation and recovery unit; The feed unit is connected to the vaporization unit through a pipeline; the product analysis unit is connected to the dehydrogenation reaction unit through a pipeline; the product condensation and recovery unit is connected to the product analysis unit through a pipeline; The dehydrogenation reaction unit includes: a pressure reducing valve (12); the pressure reducing valve (12) is arranged on the pipeline connecting the dehydrogenation reaction unit and the product analysis unit.

2. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 1, characterized in that, The product analysis unit includes: a six-way valve (13) and a gas chromatograph (14); the dehydrogenation reaction unit is connected to the gas chromatograph (14) through the six-way valve (13).

3. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 1, wherein The dehydrogenation reaction unit includes: a dehydrogenation reactor (11), a plurality of three-way control valves (18), and a heating tape (10); a three-way control valve (18) is arranged on the inlet pipeline of the dehydrogenation reactor (11); three-way control valves (18) are arranged on both the inlet and outlet pipelines of the dehydrogenation reactor (11); a heating tape (10) is arranged on the inlet pipeline of the dehydrogenation reactor (11); A heating tape (10) is arranged on the outlet pipeline of the dehydrogenation reactor (11).

4. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 3, characterized in that, The dehydrogenation reaction unit includes: a multi-stage dehydrogenation reactor (11); the upper-stage dehydrogenation reactor (11) is connected in parallel with the lower-stage dehydrogenation reactor (11) and is connected to the product analysis unit through a pipeline; each stage of dehydrogenation reactor (11) is respectively connected to the product analysis unit through a pipeline.

5. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 1, characterized in that, The vaporization unit includes: a filter (8) and a vaporizer (9); the filter (8) and the vaporizer (9) are arranged at intervals on the pipeline connecting the feed unit and the dehydrogenation reaction unit.

6. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 1, characterized in that, The feed unit includes: a hydrogen source pipe group, a nitrogen source pipe group, and a raw material tank pipe group; the hydrogen source pipe group, the nitrogen source pipe group, and the raw material tank pipe group are respectively connected to the dehydrogenation reaction unit through the vaporization unit pipeline.

7. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 6, characterized in that, The hydrogen source pipe group includes: a hydrogen source (1), a branch control valve (5), a gas mass flowmeter (6), a one-way valve (7), and a gas pressure reducing valve (26); the branch control valve (5), the gas mass flowmeter (6), the one-way valve (7), and the gas pressure reducing valve (26) are arranged at intervals on the pipeline connecting the hydrogen source (1) and the vaporization unit.

8. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 6, characterized in that, The hydrogen source pipe group includes: a hydrogen source (1), a plurality of branch pipelines (23), and a main pipe; the hydrogen source (1) is connected to the main pipe, and the main pipe is respectively connected to the dehydrogenation reaction unit pipeline through the branch pipelines (23); the branch control valve (5), the gas mass flowmeter (6), and the one-way valve (7) are arranged at intervals on the branch pipelines (23).

9. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 6, characterized in that, The nitrogen source pipe group includes: a nitrogen source (2), a branch control valve (5), a gas mass flowmeter (6), a one-way valve (7), and a gas pressure reducing valve (26); the branch control valve (5), the gas mass flowmeter (6), the one-way valve (7), and the gas pressure reducing valve (26) are arranged at intervals on the pipeline connecting the nitrogen source (2) and the vaporization unit.

10. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 6, characterized in that, The nitrogen source pipe group includes: a nitrogen source (2), a plurality of branch pipelines (23), and a main pipe; the hydrogen source (1) is connected to the main pipe, and the main pipe is respectively connected to the dehydrogenation reaction unit pipeline through the branch pipelines (23); the branch control valve (5), the gas mass flowmeter (6), and the one-way valve (7) are arranged at intervals on the branch pipelines (23).

11. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 1, characterized in that, The raw material tank pipe group includes: a raw material tank (3), a branch control valve (5), a raw material infusion pump (4), and a check valve (7); the branch control valve (5), the raw material infusion pump (4), and the check valve (7) are arranged at intervals on the pipeline connecting the raw material tank (3) and the vaporization unit.

12. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 1, characterized in that, The raw material tank pipe group includes: a raw material tank (3), a plurality of branch pipelines (23), and a main pipe; a hydrogen source (1) is connected to the main pipe, and the main pipe is respectively connected to the dehydrogenation reaction unit pipeline through the branch pipelines (23); the branch control valve (5), the raw material infusion pump (4), and the check valve (7) are arranged at intervals on the branch pipelines (23).

13. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 1, characterized in that, The product condensation recovery unit includes: a gas-liquid separator (15) and a product collection tank (16); The gas-liquid separator (15) is connected to the outlet of a gas chromatograph (14) through a six-way valve (13); the gas-liquid separator (15) is connected to the product collection tank (16) through a pipeline; a second tail gas exhaust pipeline (25) is arranged at the gas outlet of the gas-liquid separator (15).

14. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 1, wherein, It includes: A circulating cooling belt (17); the circulating cooling belt (17) is arranged on the pipeline connecting the gas-liquid separator (15) and the six-way valve (13); the circulating cooling belt (17) is wrapped on the outer wall of the gas-liquid separator (15).

15. The cyclohexane dehydrogenation to benzene catalyst evaluation device according to claim 1, characterized in that, It includes: A multi-stage dehydrogenation reaction unit, a multi-stage product analysis unit, and a multi-stage product condensation recovery unit; each stage of the dehydrogenation reaction unit and each stage of the product analysis unit are connected through pipelines; each stage of the product condensation recovery unit and each stage of the product analysis unit are connected through pipelines.

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