Raw material mixing and supply system and method for the synthesis of 2-chloro-5-trifluoromethylpyridine

Abstract

This invention relates to a raw material mixing and supply system and method for the synthesis of 2-chloro-5-trifluoromethylpyridine, belonging to the field of chemical production technology. It includes a reactor module with two raw material inlets and one product outlet, used to react a first reactant with a second reactant in a closed system under anhydrous and catalyst-free conditions. The system also includes a raw material supply unit, an online detection unit, and a control unit. The control unit receives online analysis signals from the online detection unit and calculates the adjustment amount of the first flow rate and / or the second flow rate according to a preset control model. It then sends flow adjustment commands to the first and / or second raw material metering and conveying devices to form a closed-loop control of the raw material mixing ratio. This invention has the following advantages: it can dynamically adjust the raw material flow ratio, significantly improve the control accuracy and response speed of the reaction process, and achieve precise closed-loop control of the raw material ratio.

Description

Technical Field

[0001] This invention relates to a raw material mixing and supply system and method for the synthesis of 2-chloro-5-trifluoromethylpyridine, belonging to the field of chemical production technology. Background Technology

[0002] 2-Chloro-5-trifluoromethylpyridine is a key fluorinated intermediate in the pharmaceutical, pesticide, and high-end fine chemical industries. Industrially, it is commonly synthesized using 2-chloro-5-trifluoromethylpyridine as the liquid-phase main feedstock and anhydrous hydrogen fluoride as the gas-phase auxiliary gas in a closed, anhydrous fluorination reaction system in the presence of a catalyst. The fluorination reaction is a complex multiphase process. Besides generating the target product, it may also produce some fluorinated intermediates, as well as key impurities such as over-fluorination byproducts and dechlorination byproducts. The formation of these impurities is closely related to factors such as the instantaneous ratio of raw materials, the uniformity of mixing, and the residence time.

[0003] Current technology is not comprehensive and has the following drawbacks: Traditional systems only control the total flow ratio and cannot provide real-time feedback on changes in the concentration of impurities and intermediate products. This makes it impossible to trace and adjust the source in time when impurities exceed the standard, which not only reduces the product yield but also increases the difficulty and energy consumption of post-processing distillation. It may even generate toxic and harmful waste, bringing safety and environmental hazards.

[0004] To address one of the aforementioned problems, there is an urgent need for a raw material mixing and supply system and method for the synthesis of 2-chloro-5-trifluoromethylpyridine. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is: how to achieve accurate delivery of raw materials for the synthesis of 2-chloro-5-trifluoromethylpyridine, online detection of products and closed-loop control of ratio. To this end, a raw material mixing and supply system and method for the synthesis of 2-chloro-5-trifluoromethylpyridine is provided.

[0006] The raw material mixing and supply system for the synthesis of 2-chloro-5-trifluoromethylpyridine according to the present invention includes a reactor module having two raw material inlets and one product outlet. It is used to react a first reactant with a second reactant in a closed system under anhydrous and catalyst-free conditions to obtain the finished product 2-chloro-5-trifluoromethylpyridine. Its characteristic is that...

[0007] It also includes a raw material supply unit, comprising a first raw material metering and conveying device and a second raw material metering and conveying device respectively fluidly connected to two raw material inlets. The first raw material metering and conveying device is used to convey a first reaction raw material to the reactor module at a first flow rate, and the second raw material metering and conveying device is used to convey a second reaction raw material to the reactor module at a second flow rate.

[0008] An online detection unit is located downstream of the product outlet of the reactor module and includes at least one online detection device for real-time acquisition of at least one online analysis signal among the concentrations of 2-chloro-5-trifluoromethylpyridine, key impurities, and intermediate products in the reaction product.

[0009] The control unit is electrically connected to the raw material supply unit and the online detection unit. The control unit receives the online analysis signal from the online detection unit, calculates the adjustment amount of the first flow rate and / or the second flow rate according to the preset control model, and sends the flow rate adjustment command to the first raw material metering and conveying device and / or the second raw material metering and conveying device to form a closed-loop control of the raw material mixing ratio.

[0010] In any of the above embodiments, it is preferred that the first reactant is 2-chloro-5-trichloromethylpyridine and the second reactant is hydrogen fluoride.

[0011] In any of the above embodiments, it is preferred that the raw material supply unit is divided into two independent modular feeding branches: a dedicated pressure-stabilized metering and conveying branch for main materials and a dedicated corrosion-resistant pressure-stabilized metering and conveying branch for auxiliary gas. The dedicated pressure-stabilized metering and conveying branch for main materials is adapted for sealed conveying of high-purity liquid-phase 2-chloro-5-trichloromethylpyridine molten raw materials, and is equipped with an integrated structure of explosion-proof variable frequency metering pump, high-precision electromagnetic flowmeter, and pre-pressurized buffer tank. The dedicated corrosion-resistant pressure-stabilized metering and conveying branch for auxiliary gas is adapted for corrosion-resistant quantitative conveying of high-purity gaseous raw materials of anhydrous hydrogen fluoride, and is equipped with a corrosion-resistant gas mass flowmeter, self-regulating pressure regulating valve, and leak-proof sealed flange combination structure. The two feeding branches are synchronously and independently started and stopped, independently variable frequency speed regulation, and independently pressure stabilization protection, with no cross-contamination or material interference throughout the process.

[0012] In any of the above embodiments, it is preferred that the online detection unit further includes an online sampling device, which automatically collects reaction product samples at preset time intervals and delivers them to the online detection unit.

[0013] In any of the above embodiments, it is preferred that the online detection device includes at least one of an online infrared spectrometer, an online near-infrared spectrometer, an online ultraviolet-visible spectrometer, an online Raman spectrometer, or an online gas chromatograph, and the online analysis signal includes the characteristic absorption peak intensity or characteristic chromatographic peak area corresponding to 2-chloro-5-trifluoromethylpyridine.

[0014] The method for mixing and supplying raw materials for the synthesis of 2-chloro-5-trifluoromethylpyridine is characterized by comprising the following steps:

[0015] S1: The first reaction material is continuously fed to the reactor module at a first flow rate through the first raw material metering and conveying device, and the second reaction material is continuously fed to the reactor module at a second flow rate through the second raw material metering and conveying device, so that the first reaction material and the second reaction material are mixed and reacted in the reactor module;

[0016] S2: The online detection unit collects at least one of the following online analysis signals in real time: the concentration of 2-chloro-5-trifluoromethylpyridine, the concentration of key impurities, and the concentration of intermediate products in the reaction product, and transmits the online analysis signal to the control unit;

[0017] S3: The control unit compares the actual values ​​of each concentration in the online analysis signal with the target values ​​in the preset control model. When the deviation exceeds the preset threshold, it calculates the adjustment amount of the first flow rate and / or the second flow rate.

[0018] S4: The control unit sends a flow rate adjustment command to the first raw material metering and conveying device and / or the second raw material metering and conveying device to adjust the raw material mixing ratio in real time;

[0019] S5: Repeat S2 to S4 to form a real-time closed-loop control of the raw material mixing ratio.

[0020] In any of the above schemes, the preferred method for calculating the adjustment amount in step S3 is as follows:

[0021] S31: Calculate the concentration deviation of 2-chloro-5-trifluoromethylpyridine Where C1_target is the target concentration of 2-chloro-5-trifluoromethylpyridine, and C1_actual is the actual concentration detected;

[0022] When ΔC1>0: The actual concentration is lower than the target value, and the flow rate of the second raw material needs to be increased to promote the formation of the target product.

[0023] When ΔC1<0: The actual concentration is higher than the target value, and the flow rate needs to be reduced.

[0024] S32: Calculate the critical impurity concentration deviation Where C2_actual is the actual concentration of critical impurities detected, and C2_threshold is the upper limit threshold of impurity concentration (the maximum value allowed by the process).

[0025] When ΔC2>0: impurities exceed the standard, and process adjustments are needed (usually by reducing the raw material flow rate or changing the ratio) to suppress side reactions.

[0026] When ΔC2<0: the impurities are not exceeded and no reverse adjustment is needed for the impurities.

[0027] S33: Calculate the concentration deviation of intermediate products Where C3_actual: the actual concentration of the intermediate product detected, and C3_threshold: the control threshold of the intermediate product (usually the upper limit of the optimal reaction concentration range).

[0028] When ΔC3>0: intermediate products accumulate, indicating insufficient reaction conversion. It is necessary to adjust the feed flow rate to drive the reaction towards the target product.

[0029] When ΔC3<0: The concentration of intermediate product is below the threshold, the reaction process is too fast or the raw materials are insufficient.

[0030] S34: Calculate the adjustment amount ΔQ2 of the second flow rate using the following formula:

[0031] ΔQ2 = K1·ΔC1 + K2·ΔC2 + K3·ΔC3;

[0032] Wherein, K1, K2, and K3 are preset control gain coefficients. K1 takes a positive value when ΔC1 > 0, K2 takes a positive value when ΔC2 > 0, and K3 takes a positive value when ΔC3 > 0.

[0033] S35: After applying a flow rate change limit to ΔQ2, a flow rate adjustment command for the second raw material metering and conveying device is generated.

[0034] In any of the above schemes, it is preferred to also simultaneously calculate the adjustment amount ΔQ1 of the first raw material flow rate, and calculate the adjustment amount ΔQ1 of the second flow rate using the following formula: ΔQ1 = K4·ΔC1 + K5·ΔC2 + K6·ΔC3; where ΔQ1 is the adjustment amount of the first flow rate, K4, K5, and K6 are preset control gain coefficients, and K4 takes a positive value when ΔC1 < 0 to increase the flow rate of the first reaction raw material, K5 takes a negative value when ΔC2 > 0 to decrease the flow rate of the first reaction raw material, and K6 takes a positive value when ΔC3 > 0 to increase the flow rate of the first reaction raw material.

[0035] In any of the above schemes, it is preferred that the period of the real-time closed-loop control in step S5 is 5 to 60 seconds, and the detection period of the online detection unit is less than or equal to the control period.

[0036] In any of the above schemes, it is preferred that the control gain coefficients K1, K2, and K3 are adjusted online adaptively. Based on the real-time collected product concentration response curve, the values ​​of the control gain coefficients K1, K2, and K3 are adjusted online in real time to ensure that the control effect is always close to the optimal level. Specifically, dynamic optimization is performed using recursive least squares method or fuzzy rules.

[0037] Downstream of the product discharge port, three types of core operating condition data are collected in situ online without interruption: the instantaneous actual concentration of the finished product 2-chloro-5-trifluoromethylpyridine, the instantaneous actual concentration of toxic key impurities from the fluorination side reaction, and the instantaneous actual concentration of incompletely converted intermediate products. These data are uniformly organized into standardized digital online analysis signals and uploaded in real time.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] The raw material mixing and supply system and method for the synthesis of 2-chloro-5-trifluoromethylpyridine described in this invention, by setting up an online detection unit to collect the concentration signals of the target product, key impurities and intermediate products in the reaction products in real time, and combining the linkage between the control unit and the raw material metering and conveying device, constitutes a closed-loop control system, which can dynamically adjust the raw material flow ratio, significantly improve the control accuracy and response speed of the reaction process, and realize precise closed-loop control of the raw material ratio.

[0040] The raw material mixing and supply system and method for the synthesis of 2-chloro-5-trifluoromethylpyridine described in this invention realizes full-process automation of raw material transportation, product detection, and flow rate adjustment. The closed-loop control cycle is as short as 5 seconds, and detection and control are executed simultaneously, greatly reducing manual intervention. The system can operate continuously and stably for a long time, effectively improving the production efficiency and industrial continuous production capacity of 2-chloro-5-trifluoromethylpyridine synthesis.

[0041] The raw material mixing and supply system and method for the synthesis of 2-chloro-5-trifluoromethylpyridine described in this invention adopts a completely independent modular conveying structure for the main material and auxiliary gas, which is adapted to the sealed conveying of liquid-phase molten raw materials and the corrosion-resistant conveying of gas-phase hydrogen fluoride, respectively, without cross-contamination or interference throughout the process. Detailed Implementation

[0042] The present invention will be further illustrated by specific embodiments below, but it is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0043] Example 1 describes a raw material mixing and supply system for the synthesis of 2-chloro-5-trifluoromethylpyridine, comprising a reactor module with two raw material inlets and one product outlet. This system is used to react a first reactant with a second reactant in a closed system, under anhydrous and catalyst-free conditions, to obtain the finished product, 2-chloro-5-trifluoromethylpyridine.

[0044] It also includes a raw material supply unit, comprising a first raw material metering and conveying device and a second raw material metering and conveying device respectively fluidly connected to two raw material inlets. The first raw material metering and conveying device is used to convey a first reaction raw material to the reactor module at a first flow rate, and the second raw material metering and conveying device is used to convey a second reaction raw material to the reactor module at a second flow rate.

[0045] An online detection unit is located downstream of the product outlet of the reactor module and includes at least one online detection device for real-time acquisition of at least one online analysis signal among the concentrations of 2-chloro-5-trifluoromethylpyridine, key impurities, and intermediate products in the reaction product.

[0046] The control unit is electrically connected to the raw material supply unit and the online detection unit. The control unit receives the online analysis signal from the online detection unit, calculates the adjustment amount of the first flow rate and / or the second flow rate according to the preset control model, and sends the flow rate adjustment command to the first raw material metering and conveying device and / or the second raw material metering and conveying device to form a closed-loop control of the raw material mixing ratio.

[0047] Example 2 describes a raw material mixing and supply system for the synthesis of 2-chloro-5-trifluoromethylpyridine, comprising a reactor module with two raw material inlets and one product outlet. This system is used to react the first and second reactants in a closed system, under anhydrous and catalyst-free conditions, to obtain the finished product, 2-chloro-5-trifluoromethylpyridine.

[0048] It also includes a raw material supply unit, comprising a first raw material metering and conveying device and a second raw material metering and conveying device respectively fluidly connected to two raw material inlets. The first raw material metering and conveying device is used to convey a first reaction raw material to the reactor module at a first flow rate, and the second raw material metering and conveying device is used to convey a second reaction raw material to the reactor module at a second flow rate.

[0049] An online detection unit is located downstream of the product outlet of the reactor module and includes at least one online detection device for real-time acquisition of at least one online analysis signal among the concentrations of 2-chloro-5-trifluoromethylpyridine, key impurities, and intermediate products in the reaction product.

[0050] The control unit is electrically connected to the raw material supply unit and the online detection unit. The control unit receives the online analysis signal from the online detection unit, calculates the adjustment amount of the first flow rate and / or the second flow rate according to the preset control model, and sends the flow rate adjustment command to the first raw material metering and conveying device and / or the second raw material metering and conveying device to form a closed-loop control of the raw material mixing ratio.

[0051] Furthermore, the first reaction raw material is 2-chloro-5-trichloromethylpyridine, and the second reaction raw material is hydrogen fluoride.

[0052] Furthermore, the raw material supply unit is divided into two independent modular feeding branches: a dedicated pressure-stabilized metering and conveying branch for main materials and a dedicated corrosion-resistant pressure-stabilized metering and conveying branch for auxiliary gas. The dedicated pressure-stabilized metering and conveying branch for main materials is suitable for the sealed conveying of high-purity liquid-phase 2-chloro-5-trichloromethylpyridine molten raw materials, and is equipped with an integrated structure of explosion-proof variable frequency metering pump, high-precision electromagnetic flowmeter, and pre-pressurized buffer tank. The dedicated corrosion-resistant pressure-stabilized metering and conveying branch for auxiliary gas is suitable for the corrosion-resistant quantitative conveying of high-purity gaseous raw materials of anhydrous hydrogen fluoride, and is equipped with a corrosion-resistant gas mass flowmeter, self-regulating pressure regulating valve, and leak-proof sealed flange combination structure. The two feeding branches are synchronously and independently started and stopped, independently variable frequency speed regulation, and independently pressure stabilization protection, with no cross-contamination or material interference throughout the process.

[0053] Furthermore, the online detection unit also includes an online sampling device, which automatically collects reaction product samples at preset time intervals and delivers them to the online detection unit.

[0054] Furthermore, the online detection device includes at least one of an online infrared spectrometer, an online near-infrared spectrometer, an online ultraviolet-visible spectrometer, an online Raman spectrometer, or an online gas chromatograph, and the online analysis signal includes the characteristic absorption peak intensity or characteristic chromatographic peak area corresponding to 2-chloro-5-trifluoromethylpyridine.

[0055] Example 3, the method for mixing and supplying raw materials for the synthesis of 2-chloro-5-trifluoromethylpyridine, includes the following steps:

[0056] S1: The first reaction material is continuously fed to the reactor module at a first flow rate through the first raw material metering and conveying device, and the second reaction material is continuously fed to the reactor module at a second flow rate through the second raw material metering and conveying device, so that the first reaction material and the second reaction material are mixed and reacted in the reactor module;

[0057] S2: The online detection unit collects at least one of the following online analysis signals in real time: the concentration of 2-chloro-5-trifluoromethylpyridine, the concentration of key impurities, and the concentration of intermediate products in the reaction product, and transmits the online analysis signal to the control unit;

[0058] S3: The control unit compares the actual values ​​of each concentration in the online analysis signal with the target values ​​in the preset control model. When the deviation exceeds the preset threshold, it calculates the adjustment amount of the first flow rate and / or the second flow rate.

[0059] S4: The control unit sends a flow rate adjustment command to the first raw material metering and conveying device and / or the second raw material metering and conveying device to adjust the raw material mixing ratio in real time;

[0060] S5: Repeat S2 to S4 to form a real-time closed-loop control of the raw material mixing ratio.

[0061] In any of the above schemes, the preferred method for calculating the adjustment amount in step S3 is as follows:

[0062] S31: Calculate the concentration deviation of 2-chloro-5-trifluoromethylpyridine Where C1_target is the target concentration of 2-chloro-5-trifluoromethylpyridine, and C1_actual is the actual concentration detected;

[0063] When ΔC1>0: The actual concentration is lower than the target value, and the flow rate of the second raw material needs to be increased to promote the formation of the target product.

[0064] When ΔC1<0: The actual concentration is higher than the target value, and the flow rate needs to be reduced.

[0065] S32: Calculate the critical impurity concentration deviation Where C2_actual is the actual concentration of critical impurities detected, and C2_threshold is the upper limit threshold of impurity concentration (the maximum value allowed by the process).

[0066] When ΔC2>0: impurities exceed the standard, and process adjustments are needed (usually by reducing the raw material flow rate or changing the ratio) to suppress side reactions.

[0067] When ΔC2<0: the impurities are not exceeded and no reverse adjustment is needed for the impurities.

[0068] S33: Calculate the concentration deviation of intermediate products Where C3_actual: the actual concentration of the intermediate product detected, and C3_threshold: the control threshold of the intermediate product (usually the upper limit of the optimal reaction concentration range).

[0069] When ΔC3>0: intermediate products accumulate, indicating insufficient reaction conversion. It is necessary to adjust the feed flow rate to drive the reaction towards the target product.

[0070] When ΔC3<0: The concentration of intermediate product is below the threshold, the reaction process is too fast or the raw materials are insufficient.

[0071] S34: Calculate the adjustment amount ΔQ2 of the second flow rate using the following formula:

[0072] ΔQ2 = K1·ΔC1 + K2·ΔC2 + K3·ΔC3;

[0073] Wherein, K1, K2, and K3 are preset control gain coefficients. K1 takes a positive value when ΔC1 > 0, K2 takes a positive value when ΔC2 > 0, and K3 takes a positive value when ΔC3 > 0.

[0074] S35: After applying a flow rate change limit to ΔQ2, a flow rate adjustment command for the second raw material metering and conveying device is generated.

[0075] In any of the above schemes, it is preferred to also simultaneously calculate the adjustment amount ΔQ1 of the first raw material flow rate, and calculate the adjustment amount ΔQ1 of the second flow rate using the following formula: ΔQ1 = K4·ΔC1 + K5·ΔC2 + K6·ΔC3; where ΔQ1 is the adjustment amount of the first flow rate, K4, K5, and K6 are preset control gain coefficients, and K4 takes a positive value when ΔC1 < 0 to increase the flow rate of the first reaction raw material, K5 takes a negative value when ΔC2 > 0 to decrease the flow rate of the first reaction raw material, and K6 takes a positive value when ΔC3 > 0 to increase the flow rate of the first reaction raw material.

[0076] In any of the above schemes, it is preferred that the period of the real-time closed-loop control in step S5 is 5 to 60 seconds, and the detection period of the online detection unit is less than or equal to the control period.

[0077] In any of the above schemes, it is preferred that the control gain coefficients K1, K2, and K3 are adjusted online adaptively. Based on the real-time collected product concentration response curve, the values ​​of the control gain coefficients K1, K2, and K3 are adjusted online in real time to ensure that the control effect is always close to the optimal level. Specifically, dynamic optimization is performed using recursive least squares method or fuzzy rules.

[0078] Downstream of the product discharge port, three types of core operating condition data are collected in situ online without interruption: the instantaneous actual concentration of the finished product 2-chloro-5-trifluoromethylpyridine, the instantaneous actual concentration of toxic key impurities from the fluorination side reaction, and the instantaneous actual concentration of incompletely converted intermediate products. These data are uniformly organized into standardized digital online analysis signals and uploaded in real time.

[0079] It can accurately and stably deliver and mix raw materials, dynamically correct reaction deviations in real time, significantly improve the synthesis yield and product purity of 2-chloro-5-trifluoromethylpyridine, effectively suppress the generation of key impurities and the accumulation of intermediate products, and achieve inherently safe delivery and zero leakage protection for high-risk media such as hydrogen fluoride, reducing equipment corrosion and production risks. The fully automated closed-loop operation greatly improves the level of production continuity and the stability of equipment operation, perfectly adapting to complex industrial conditions and meeting the high-efficiency, stable, green and safe production needs of high-end fine chemicals.

[0080] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

[0081] Any aspects of this invention not described in detail are well-known to those skilled in the art.

Claims

1. A raw material mixing and supply system for the synthesis of 2-chloro-5-trifluoromethylpyridine, comprising a reactor module having two raw material inlets and one product outlet, for reacting a first reactant with a second reactant in a closed system under anhydrous and catalyst-free conditions to obtain the finished product 2-chloro-5-trifluoromethylpyridine, characterized in that, It also includes a raw material supply unit, comprising a first raw material metering and conveying device and a second raw material metering and conveying device respectively fluidly connected to two raw material inlets. The first raw material metering and conveying device is used to convey a first reaction raw material to the reactor module at a first flow rate, and the second raw material metering and conveying device is used to convey a second reaction raw material to the reactor module at a second flow rate. An online detection unit is located downstream of the product outlet of the reactor module and includes at least one online detection device for real-time acquisition of at least one online analysis signal among the concentrations of 2-chloro-5-trifluoromethylpyridine, key impurities, and intermediate products in the reaction product. The control unit is electrically connected to the raw material supply unit and the online detection unit. The control unit receives the online analysis signal from the online detection unit, calculates the adjustment amount of the first flow rate and / or the second flow rate according to the preset control model, and sends the flow rate adjustment command to the first raw material metering and conveying device and / or the second raw material metering and conveying device to form a closed-loop control of the raw material mixing ratio.

2. The raw material mixing and supply system for the synthesis of 2-chloro-5-trifluoromethylpyridine according to claim 1, characterized in that, The first reaction raw material is 2-chloro-5-trichloromethylpyridine, and the second reaction raw material is hydrogen fluoride.

3. The raw material mixing and supply system for the synthesis of 2-chloro-5-trifluoromethylpyridine according to claim 2, characterized in that, The raw material supply unit consists of two independent modular feeding branches: a dedicated pressure-stabilized metering and conveying branch for main materials and a dedicated corrosion-resistant pressure-stabilized metering and conveying branch for auxiliary gas. The dedicated pressure-stabilized metering and conveying branch for main materials is suitable for the sealed conveying of high-purity liquid-phase 2-chloro-5-trichloromethylpyridine molten raw materials, and is equipped with an explosion-proof variable frequency metering pump, a high-precision electromagnetic flowmeter, and a pre-pressurized buffer tank integrated structure. The dedicated corrosion-resistant pressure-stabilized metering and conveying branch for auxiliary gas is suitable for the corrosion-resistant quantitative conveying of high-purity anhydrous hydrogen fluoride gaseous raw materials, and is equipped with a corrosion-resistant gas mass flowmeter, a self-regulating pressure regulating valve, and a leak-proof sealed flange combination structure. The two feeding branches can be started and stopped synchronously and independently, with independent variable frequency speed regulation and independent pressure stabilization protection, and there is no cross-contamination or material interference throughout the process.

4. The raw material mixing and supply system for the synthesis of 2-chloro-5-trifluoromethylpyridine according to claim 3, characterized in that, The online detection unit also includes an online sampling device, which automatically collects reaction product samples at preset time intervals and transports them to the online detection unit.

5. The method for mixing and supplying raw materials for the synthesis of 2-chloro-5-trifluoromethylpyridine according to claim 4, characterized in that, The online detection device includes at least one of an online infrared spectrometer, an online near-infrared spectrometer, an online ultraviolet-visible spectrometer, an online Raman spectrometer, or an online gas chromatograph, and the online analysis signal includes the characteristic absorption peak intensity or characteristic chromatographic peak area corresponding to 2-chloro-5-trifluoromethylpyridine.

6. The method for mixing and supplying raw materials for the synthesis of 2-chloro-5-trifluoromethylpyridine according to any one of claims 1-5, characterized in that, Includes the following steps, S1: The first reaction material is continuously fed to the reactor module at a first flow rate through the first raw material metering and conveying device, and the second reaction material is continuously fed to the reactor module at a second flow rate through the second raw material metering and conveying device, so that the first reaction material and the second reaction material are mixed and reacted in the reactor module; S2: The online detection unit collects at least one of the following online analysis signals in real time: the concentration of 2-chloro-5-trifluoromethylpyridine, the concentration of key impurities, and the concentration of intermediate products in the reaction product, and transmits the online analysis signal to the control unit; S3: The control unit compares the actual values ​​of each concentration in the online analysis signal with the target values ​​in the preset control model. When the deviation exceeds the preset threshold, it calculates the adjustment amount of the first flow rate and / or the second flow rate. S4: The control unit sends a flow rate adjustment command to the first raw material metering and conveying device and / or the second raw material metering and conveying device to adjust the raw material mixing ratio in real time; S5: Repeat S2 to S4 to form a real-time closed-loop control of the raw material mixing ratio.

7. The method for mixing and supplying raw materials for the synthesis of 2-chloro-5-trifluoromethylpyridine according to claim 1, characterized in that, The method for calculating the adjustment amount in step S3 is as follows: S31: Calculate the concentration deviation of 2-chloro-5-trifluoromethylpyridine Where C1_target is the target concentration of 2-chloro-5-trifluoromethylpyridine, and C1_actual is the actual detected concentration; S32: Calculate the critical impurity concentration deviation Where C2_actual is the actual concentration of the critical impurity detected, and C2_threshold is the upper limit threshold of the impurity concentration; S33: Calculate the concentration deviation of intermediate products Where, C3_actual: the actual concentration of the intermediate product detected, and C3_threshold: the control threshold for the intermediate product; S34: Calculate the adjustment amount ΔQ2 of the second flow rate using the following formula: ΔQ2 = K1·ΔC1 + K2·ΔC2 + K3·ΔC3; Wherein, K1, K2, and K3 are preset control gain coefficients. K1 takes a positive value when ΔC1 > 0, K2 takes a positive value when ΔC2 > 0, and K3 takes a positive value when ΔC3 > 0. S35: After applying a flow rate change limit to ΔQ2, a flow rate adjustment command for the second raw material metering and conveying device is generated.

8. The method for mixing and supplying raw materials for the synthesis of 2-chloro-5-trifluoromethylpyridine according to claim 1, characterized in that, Simultaneously, the adjustment amount ΔQ1 of the first raw material flow rate is calculated, and the adjustment amount ΔQ1 of the second flow rate is calculated using the following formula: ΔQ1 = K4·ΔC1 + K5·ΔC2 + K6·ΔC3; where ΔQ1 is the adjustment amount of the first flow rate, K4, K5, and K6 are preset control gain coefficients, and K4 takes a positive value to increase the flow rate of the first reaction raw material when ΔC1 < 0, K5 takes a negative value to decrease the flow rate of the first reaction raw material when ΔC2 > 0, and K6 takes a positive value to increase the flow rate of the first reaction raw material when ΔC3 > 0.

9. The method for mixing and supplying raw materials for the synthesis of 2-chloro-5-trifluoromethylpyridine according to claim 1, characterized in that, The real-time closed-loop control cycle in step S5 is 5 to 60 seconds, and the detection cycle of the online detection unit is less than or equal to the control cycle.

10. The method for mixing and supplying raw materials for the synthesis of 2-chloro-5-trifluoromethylpyridine according to claim 1, characterized in that, The control gain coefficients K1, K2, and K3 are adjusted online adaptively based on the real-time product concentration response curve.