Catalyst evaluation and process optimization device based on fixed bed microreactor
Through the multi-channel design and central control system based on fixed-bed microreactor, the problem of single design and narrow process conditions of the existing catalyst evaluation device is solved, and the efficient process optimization of simultaneous evaluation of multiple catalysts and multi-reaction types is achieved, which improves the catalyst Evaluation efficiency and reaction efficiency.
Patent Information
- Application Number
- CN202420840432.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-22
- Publication Date
- 2024-12-20
- Estimated Expiration
- 2034-04-22
AI Technical Summary
The existing catalyst evaluation device has a single design, a narrow range of process conditions and poor applicability. It is difficult to evaluate multiple catalysts at the same time and the reaction types are diverse, resulting in low evaluation efficiency and poor mixing conditions, which requires repeated filling and rinsing.
Using a multi-channel design based on a fixed bed micro reactor, combined with a central control system, feed system, gas-liquid mixing system and reactant recovery system, the simultaneous evaluation of multiple catalysts and independent process conditions control are realized, through the T-type micro shear and multi-channel microtube design improves gas-liquid mixing efficiency and fluid contact area within the reactor.
It improves the working efficiency of catalyst evaluation, meets the needs of various reaction types, reduces repeated loading and operation, realizes stable experimental conditions and efficient chemical reactions, and reduces energy consumption and operating costs.
Smart Images
Figure CN222196886U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to catalyst evaluation equipment, and in particular to a catalyst evaluation and process optimization device based on a fixed bed microreactor. Background Art
[0002] Catalytic reaction technology has important applications in many fields, and more than 70% of chemical processes require the use of catalytic technology for production.
[0003] At present, most catalyst evaluation devices are designed for a specific reaction type, usually single-channel catalyst evaluation devices, that is, single-tube designs under single systems, with narrow process condition adjustment ranges and poor applicability. When evaluating and testing multiple different catalysts, it is necessary to conduct experimental research on one catalyst at a time in one reactor, which is a long process and requires flushing, drying, and repeated filling operations. In addition, the internal mixing state is poor, and the evaluation efficiency is low. Summary of the invention
[0004] Based on the problems existing in the prior art, the utility model aims to provide a catalyst evaluation and process optimization device based on a fixed bed microreactor, which can evaluate multiple catalysts at the same time and independently control different process conditions, thereby improving the efficiency of catalyst evaluation work and meeting the needs of various different reaction types.
[0005] In order to achieve the above-mentioned purpose, the utility model discloses a catalyst evaluation and process optimization device based on a fixed bed microreactor, comprising a central control system, a feeding system, a gas-liquid mixing system, and a plurality of fixed bed microreactors, wherein the gas-liquid mixing system comprises a plurality of gas-liquid mixing modules, and the gas-liquid mixing modules correspond to and are connected with the fixed bed microreactors one by one, the feeding system comprises a liquid storage component and a gas storage component, the liquid storage component is connected with each gas-liquid mixing module through a liquid inlet pipeline, the gas storage component is connected with each gas-liquid mixing module through a gas pipeline, an infusion pump is provided on the liquid inlet pipeline, a stop valve, a pressure reducing valve and a gas flow control system are provided on the gas pipeline, and the infusion pump, the stop valve, the pressure reducing valve and the gas flow control system are all electrically connected to the central control system.
[0006] Furthermore, the catalyst evaluation and process optimization device also includes a preheating system, which is arranged on the liquid inlet pipeline, the inlet of the preheating system is connected to the infusion pump, and the outlet of the preheating system is connected to each gas-liquid mixing module.
[0007] Furthermore, a T-shaped micro-shear is provided inside the gas-liquid mixing module, and the T-shaped micro-shear is used to divide the mixed gas and liquid into micro-bubbles and micro-droplets with a size between 10-1000 μm.
[0008] Furthermore, the interior of the fixed bed microreactor is designed with multi-channel microtubes.
[0009] Furthermore, the gas flow control system is a mass flow meter, and the gas storage assembly includes a reaction gas bottle and a purge gas bottle. The gas pipelines of the reaction gas bottle and the purge gas bottle are connected in parallel and are connected to the mass flow meter, and are respectively connected to each gas-liquid mixing module through the mass flow meter.
[0010] Furthermore, the catalyst evaluation and process optimization device also includes a reactant recovery system, which includes a condenser and a gas-liquid separator. The outlet of the fixed bed microreactor is connected to the condenser and the gas-liquid separator in sequence. The gas outlet of the gas-liquid separator is connected to a gas buffer device and a drying tank in sequence, and the liquid outlet of the gas-liquid separator is connected to a filter and a sampling device in sequence.
[0011] Furthermore, the liquid storage component includes a plurality of liquid storage tanks, the preheating system has a plurality of independent heating channels, the liquid storage tanks, infusion pumps and heating channels correspond to each other one by one and are connected in sequence, the heating channels are provided with independent temperature control devices, the liquid outlets of each heating channel are connected to the liquid inlets of each gas-liquid mixing module by a temperature control pipeline, and the temperature control pipeline is provided with a heating and insulation control device.
[0012] Furthermore, the gas pipeline is also provided with one or more of a filter, a pressure stabilizing valve, a back pressure valve, and a dryer.
[0013] Through the above technical solution, multiple fixed bed systems are connected in parallel, which can simultaneously evaluate multiple groups of catalysts and optimize independent processes, thereby improving the efficiency of catalyst evaluation work and meeting the needs of various different reaction types. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The specific implementation of the utility model is further described in detail below with reference to the accompanying drawings.
[0015] Figure 1 It is a schematic structural diagram of the catalyst evaluation and process optimization device based on a fixed bed microreactor of the utility model. Specific implementation plan
[0016] In order to explain the present invention more clearly, the present invention is further described below in conjunction with preferred embodiments. Those skilled in the art should understand that the following specific description is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.
[0017] The utility model is a catalyst evaluation and process optimization device based on a fixed bed microreactor, comprising a central control system, a feeding system consisting of a liquid storage component and a gas storage component, a gas-liquid mixing system, a plurality of fixed bed microreactors and a reactant recovery system, wherein the gas-liquid mixing system comprises a plurality of gas-liquid mixing modules, the gas-liquid mixing modules correspond to and are connected with the fixed bed microreactors one by one, the liquid storage component is connected with each gas-liquid mixing module through a liquid inlet pipeline, the gas storage component is connected with each gas-liquid mixing module through a gas pipeline, an infusion pump is arranged on the liquid inlet pipeline, a stop valve, a pressure reducing valve and a gas flow control system are arranged on the gas pipeline, and the infusion pump, the stop valve, the pressure reducing valve and the gas flow control system are all electrically connected with the central control system.
[0018] The entire system of the utility model is an integrated device and is controlled by the same central control system. When the reaction conditions, reaction pressure, gas flow rate, etc. need to be kept consistent, more stable experimental conditions can be obtained, avoiding the problem of pressure and flow fluctuations caused by different devices.
[0019] In addition, the utility model sets up multiple fixed bed microreactors in parallel, and different catalysts can be set in each fixed bed microreactor, and other conditions are controlled by the control system to be the same, so that the catalyst can be evaluated quickly and efficiently; multiple fixed bed microreactors can also be placed with the same catalyst, and other reaction conditions are controlled by the central control system to be different, so as to perform process comparison and achieve process optimization. In summary, the utility model can be tested simultaneously, without repeated disassembly and assembly, one-time loading, and simultaneous operation, and multiple groups of results can be obtained, which improves efficiency.
[0020] As a preferred embodiment of the utility model, the catalyst evaluation and process optimization device also includes a preheating system, which preheats the raw liquid, and the liquid outlet channels of the preheating system are respectively connected to the liquid inlets of the corresponding gas-liquid mixing modules. The raw liquid and the gas are premixed in the gas-liquid mixing module and then sent to the interior of the fixed bed microreactor. The fixed bed microreactor is filled with the catalyst required for the reaction, and the gas and liquid react on the surface of the catalyst. The fixed bed microreactor is provided with a reactor heating and temperature control device outside. The reacted gas and liquid are sent to the condenser and the gas-liquid separation system, and are discharged or collected after gas-liquid separation.
[0021] A preheating system is used to preheat the raw liquid before mixing it with the reaction gas, thus avoiding heating of the gas outside the fixed bed microreactor and further improving safety performance.
[0022] As a preferred embodiment of the utility model, the gas pipeline is also provided with one or more of a filter, a pressure regulating valve, a back pressure valve, a dryer, etc., to accurately control the reaction conditions for different reaction systems, further reduce by-products, and improve selectivity.
[0023] like Figure 1 The catalyst evaluation and process optimization device shown in the figure has a liquid storage tank 1, a high-pressure horizontal flow pump 2, a preheating channel 3 of the preheating system, a gas-liquid mixer 5, a fixed bed microreactor 4, a reaction gas bottle 12, and a reactant recovery system, each of which has three parts. The liquid storage tank 1, the high-pressure horizontal flow pump 2, the preheating channel 3, the gas-liquid mixer 5, and the fixed bed microreactor 4 are all in one-to-one correspondence and are connected in sequence. The reaction gas bottle 12 is connected to each gas-liquid mixer 5 in one-to-one correspondence through a gas pipeline, and a pressure reducing valve 8, a stop valve 11, and a mass flow meter 10 are sequentially provided in the direction from the gas bottle outlet 12 to the gas-liquid mixer 5 inlet. The gas storage assembly also includes a purge gas bottle 6, and a pressure reducing valve and a stop valve are sequentially provided on the outlet pipeline of the purge gas bottle 6, and the purge gas bottle 6 is connected to the gas pipeline of each reaction gas bottle 12 through a gas pipeline, and the connection point is located between the mass flow meter 10 and the stop valve of the reaction gas bottle 12, and a stop valve 11 is provided near the connection point. The pressure reducing valve, the stop valve and the mass flow meter in the device of the utility model are all electrically connected to the central control system.
[0024] Each heating channel 3 is provided with an independent temperature control device, and the liquid outlet of each heating channel 3 is connected to the liquid inlet of each gas-liquid mixer 5 by a temperature control pipeline, and a heating and heat preservation control device is provided on the temperature control pipeline. Each fixed bed microreactor 4 is provided with an independent temperature control device, and the heating and heat preservation control device and the temperature control device are electrically connected to the central control system.
[0025] The outlets of the fixed bed microreactor 4 are connected in sequence to a condenser 71 and a gas-liquid separator 72, the gas outlet of the gas-liquid separator 72 is connected in sequence to a gas buffer device 74 and a drying tank 75, and the liquid outlet of the gas-liquid separator 72 is connected in sequence to a filter 73 and a sampling device 77.
[0026] As a preferred embodiment of the utility model, a T-type micro-shear is provided inside the gas-liquid mixer 5, and the T-type micro-shear is electrically connected to the central control system. The central control system controls the T-type micro-shear to divide the mixed gas and liquid into micro-bubbles and micro-droplets, and the size of the micro-bubbles and micro-droplets can be controlled and adjusted between 10-1000μm.
[0027] Microbubbles and microdroplets greatly increase the contact area between gas and liquid, while promoting more uniform mixing, thereby accelerating the rate of chemical reactions. Microbubbles and microdroplets reduce the resistance to mass transfer, making the dissolution and diffusion processes more efficient. Due to the enhanced mass transfer and mixing effects, reactions can be carried out under milder conditions, which is particularly important for reactions that require precise control, where microbubbles and microdroplets can help achieve higher product selectivity and lower by-product generation. The use of microshear technology can achieve efficient gas-liquid reactions at lower energy input because it reduces the required stirring intensity and the required reaction volume, thereby reducing operating costs and energy consumption.
[0028] As a preferred embodiment of the present utility model, the interior of the fixed bed microreactor is designed with a multi-channel microtube. The tube size is in the range of 50-50000 μm; the catalyst particle size in the fixed bed microreactor is selected in the range of 40-1000 μm. The multi-channel microtube design can increase the contact surface area between the liquid and the gas in the reactor, thereby improving the mass transfer efficiency and promoting the mixing and reaction rate between the reactants. By designing a reasonable multi-channel structure, the uniform flow distribution of the fluid in the reactor can be achieved, avoiding the uneven phenomenon of the reaction materials caused by the local flow rate of the fluid being too fast or too slow, which is conducive to maintaining the stability and consistency of the reaction. The microtube design can reduce the resistance of the fluid in the pipeline and reduce the pressure drop generated when the fluid flows, thereby reducing energy consumption and improving energy utilization efficiency. At the same time, the multi-channel microtube design can more accurately control the reaction conditions, such as temperature, pressure, flow rate, etc., making the reaction process more controllable, which is conducive to achieving efficient chemical reactions.
[0029] The temperature range of each heating channel 3 inside the preheating system is adjustable between 20°C and 200°C. During the reaction of the catalyst, all process conditions can be independently controlled. The preset temperature range of the reactor is adjustable between 20°C and 600°C, the preset pressure range is adjustable between 0-10MPa, and the residence time of the gas-liquid mixture in the fixed bed microreactor is controllable within 1-20min.
[0030] To help understand the present invention, the following examples are given for the use of the present invention:
[0031] 1) hydrogenation reaction catalysts of different types and preset masses are sequentially loaded into different fixed bed microreactors;
[0032] 2) respectively setting the preheating temperature of the preheating system, the temperature of the temperature control pipeline, and the heating temperature of the fixed bed microreactor;
[0033] 3) Setting the feed flow rates of the raw material liquid and the reaction gas to ensure that the gas and the preheated liquid raw material are fully mixed in the gas-liquid mixing system to obtain a gas-liquid mixture at a microscale;
[0034] 4) The gas-liquid mixture is fed into a fixed bed microreactor, and a catalytic reaction is carried out at independently controllable preset temperature, preset pressure, and preset flow rate to obtain a liquid product, and the catalyst and process are evaluated.
[0035] The following is a specific example 1 of catalyst screening:
[0036] The fixed bed microreactor catalyst rapid evaluation and process development device is used to simultaneously evaluate three catalysts for the hydrogenation reaction of 2,4-dichloronitrobenzene. The specific implementation plan is as follows:
[0037] Raw materials: 10% mass concentration of 2,4-dichloronitrobenzene and methanol mixed solution.
[0038] (1) Check the air tightness of the device.
[0039] (2) Take an appropriate amount of Pd / Al 2 0 3 , Pd / C, and Pt / C catalysts are loaded in fixed bed microreactor 1, fixed bed microreactor 2, and fixed bed microreactor 3, respectively.
[0040] (3) Turn on the nitrogen purge gas, and simultaneously start and set the temperatures of the three preheating systems to 40°C and the reaction temperature of the fixed bed microreactor to 60°C.
[0041] (4) After the heating system reaches the set temperature and remains stable for 5-10 minutes, turn off the purge gas. Open the three reaction gas bottles in sequence. The reaction pressure is controlled to 1.0 MPa and the hydrogen flow rate is 10 mL / min through the pressure reducing valve, back pressure valve and mass flow meter on the gas pipeline.
[0042] (5) Turn on the infusion pump, set the liquid flow rate to 0.2 mL / min, and deliver the mixed solution of 2,4-dichloronitrobenzene and methanol. Pre-mix the heated raw liquids from each channel with each gas, and the resulting gas-liquid mixture enters the corresponding fixed bed microreactor.
[0043] (6) Take the product liquid from the sampling device for analysis and testing.
[0044] The test results of the fixed bed microreactor 1 product: dichloronitrobenzene conversion rate 70.00%, product dichloroaniline selectivity 90.50%; the test results of the fixed bed microreactor 2 product: dichloronitrobenzene conversion rate 79.10%, product aniline selectivity 91.30%; the test results of the fixed bed microreactor 3 product: nitrobenzene conversion rate 100.00%, product aniline selectivity 99.88%.
[0045] The Pt / C catalyst in the fixed bed microreactor 3 was screened out to be the best.
[0046] The following is Example 2 of reaction temperature screening of fixed bed microreactor:
[0047] Based on the Pt / C catalyst with better results in Example 1, keeping other conditions unchanged, the reaction temperature of the fixed bed microreactor was optimized. The reaction temperatures of the three fixed bed microreactors were set to 60°C, 80°C, and 100°C, respectively.
[0048] The product liquid was taken from the sampling device for analysis and testing. The test results of the fixed bed microreactor 1 product: nitrobenzene conversion rate 100.00%, product aniline selectivity 99.88%; the test results of the fixed bed microreactor 2 product: nitrobenzene conversion rate 100.00%, product aniline selectivity 99.98%; the test results of the fixed bed microreactor 3 product: nitrobenzene conversion rate 100.00%, product aniline selectivity 99.55%.
[0049] The optimal reaction temperature in the fixed bed microreactor was screened out to be 80℃.
[0050] The following is Example 3 of reaction pressure screening of fixed bed microreactor:
[0051] Based on the Pt / C catalyst in Example 1, at the reaction temperature with high raw material conversion rate and product selectivity in Example 2, keeping other conditions unchanged, the reaction pressure was optimized. The reaction pressures were controlled to 1MPa, 2MPa, and 3MPa respectively through the pressure reducing valve and back pressure valve on the gas pipeline.
[0052] The product liquid was taken from the sampling device for analysis and testing. The test results of the fixed bed microreactor 1 product: nitrobenzene conversion rate 100.00%, product aniline selectivity 99.98%; the test results of the fixed bed microreactor 2 product: nitrobenzene conversion rate 100.00%, product aniline selectivity 99.95%; the test results of the fixed bed microreactor 3 product: nitrobenzene conversion rate 100.00%, product aniline selectivity 99.73%.
[0053] As the pressure increases, the product selectivity decreases, and the optimal reaction pressure in the fixed bed microreactor is screened out to be 1 MPa.
Claims
1. A catalyst evaluation and process optimization device based on a fixed bed microreactor, characterized in that: It includes a central control system, a feeding system, a gas-liquid mixing system, and several fixed-bed microreactors. The gas-liquid mixing system includes several gas-liquid mixing modules, and the gas-liquid mixing modules correspond to and are connected with the fixed-bed microreactors one by one. The feeding system includes a liquid storage component and a gas storage component. The liquid storage component is connected with each gas-liquid mixing module through a liquid inlet pipeline, and the gas storage component is connected with each gas-liquid mixing module through a gas pipeline. An infusion pump is provided on the liquid inlet pipeline, and a stop valve, a pressure reducing valve and a gas flow control system are provided on the gas pipeline. The infusion pump, the stop valve, the pressure reducing valve and the gas flow control system are all electrically connected to the central control system.
2. The catalyst evaluation and process optimization device according to claim 1, characterized in that: It also includes a preheating system, which is arranged on the liquid inlet pipeline, the inlet of the preheating system is connected to the infusion pump, and the outlet of the preheating system is connected to each gas-liquid mixing module.
3. The catalyst evaluation and process optimization device according to claim 1 or 2, characterized in that: A T-shaped micro-shear is provided inside the gas-liquid mixing module, and the T-shaped micro-shear is used to divide the mixed gas and liquid into micro-bubbles and micro-droplets with a size between 10-1000 μm.
4. The catalyst evaluation and process optimization device according to claim 3, characterized in that: The interior of the fixed bed microreactor is designed as a multi-channel microtube.
5. The catalyst evaluation and process optimization device according to claim 4, characterized in that: The gas flow control system is a mass flow meter, and the gas storage assembly includes a reaction gas bottle and a purge gas bottle. The gas pipelines of the reaction gas bottle and the purge gas bottle are connected in parallel and connected to the mass flow meter, and are connected to each gas-liquid mixing module respectively through the mass flow meter.
6. The catalyst evaluation and process optimization device according to claim 5, characterized in that: It also includes a reactant recovery system, which includes a condenser and a gas-liquid separator. The outlet of the fixed bed microreactor is connected to the condenser and the gas-liquid separator in sequence. The gas outlet of the gas-liquid separator is connected to a gas buffer device and a drying tank in sequence. The liquid outlet of the gas-liquid separator is connected to a filter and a sampling device in sequence.
7. The catalyst evaluation and process optimization device according to claim 2, characterized in that: The liquid storage component includes a plurality of liquid storage tanks, and the preheating system has a plurality of independent heating channels. The liquid storage tanks, infusion pumps and heating channels correspond to each other one by one and are connected in sequence. The heating channels are provided with independent temperature control devices. The liquid outlets of each heating channel are connected to the liquid inlets of each gas-liquid mixing module by a temperature control pipeline, and the temperature control pipeline is provided with a heating and heat preservation control device.
8. The catalyst evaluation and process optimization device according to claim 7, characterized in that: The gas pipeline is also provided with one or more of a filter, a pressure stabilizing valve, a back pressure valve and a dryer.