Active black 5 continuous synthesis method based on segmented sampling monitoring

Abstract

The invention is applied to the technical field of reactive black 5 synthesis, and particularly discloses a continuous reactive black 5 synthesis method based on sectional sampling monitoring, which comprises the following steps: S1, a first module reaction section: inputting a para-ester-hydrochloric acid aqueous solution and a sodium nitrite solution into a mixer for mixing; s2, a second module reaction section: inputting the material in the buffer tank V1 into a reactor R3, adding H acid slurry, and mixing; s3, in a third module reaction section, the materials in the buffer tank V2 are input into a reactor R5, and finally products are conveyed to a post-treatment unit. According to the active black 5 continuous synthesis method based on segmented sampling monitoring, a three-section continuous reaction is adopted, and sampling units I, II and V are respectively arranged at key nodes of a first module reaction section, a second module reaction section and a third module reaction section, namely after a reactor R1, after a reactor R2, after a reactor R3, after a reactor R4 and after a reactor R5.

Description

Technical Field

[0001] This invention relates to the field of active black 5 synthesis technology, specifically to a continuous synthesis method for active black 5 based on segmented sampling and monitoring. Background Technology

[0002] Reactive Black 5, as a widely used dual reactive azo dye, occupies an important position in the dyeing of natural fibers such as cotton, linen, and silk due to its advantages such as low price, directness, and good leveling properties. Its usage accounts for more than 60% of the total amount of reactive dyes and is the core component in the black dye color matching system.

[0003] In existing continuous synthesis technologies, the reaction process is mostly an integrated series design. Because each reaction stage of the synthesis of Reactive Black 5 has strict requirements for parameters such as raw material ratio, temperature, and pH value, and minor abnormalities in the preceding reactions can be accumulated and amplified through material transfer, leading to a complete loss of control in subsequent reactions and ultimately affecting the quality of the finished product. Existing processes only test the final product after the entire synthesis process is completed, and cannot monitor the material status of each intermediate reaction stage in real time. When a product is found to be unqualified, it is difficult to quickly trace the source of the abnormality, thus affecting the continuity of production. Summary of the Invention

[0004] The purpose of this invention is to provide a continuous synthesis method for Reactive Black 5 based on segmented sampling and monitoring, in order to solve the problem mentioned in the background art that the source of abnormal reaction cannot be quickly traced during the continuous synthesis of Reactive Black 5, which affects the continuity of production.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a continuous synthesis method for active black 5 based on segmented sampling and monitoring, comprising the following steps: S1, Module 1 Reaction Section: Para-ester-hydrochloric acid aqueous solution and sodium nitrite solution are fed into the mixer and mixed, then fed into reactor R1. After the reaction is completed, the state of the reaction solution is monitored by sampling unit one. Aminosulfonic acid slurry is added to the reaction solution, mixed by reactor R2, and then sampled and monitored by sampling unit two before entering buffer tank V1 for temporary storage. S2, Module 2 Reaction Section: The material in buffer tank V1 is fed into reactor R3, H acid slurry is added and mixed. After mixing, the reaction liquid is sampled by sampling unit three to monitor the state of the reaction liquid, and then fed into reactor R4. After the reaction is completed, the reaction liquid is sampled by sampling unit four to monitor the state of the reaction liquid, and then sent to buffer tank V2 for temporary storage. S3, Module 3 Reaction Section: The material in buffer tank V2 is fed into reactor R5, and sodium bicarbonate slurry is added to react and mix. After sampling and monitoring the product status by sampling unit 5, the product enters receiving tank V3 and is finally transported to the post-processing unit. Preferably, the reaction section of module S1 includes a mixer. The inlet of the mixer is connected to raw material tanks T1 and T2 via pipes. The outlet of the mixer is connected to reactor R1 via pipes. The outlet of reactor R1 is connected to the inlet of sampling unit one. The outlet of sampling unit one is connected to the inlet of reactor R2. The inlet of reactor R2 is connected to raw material tank T3. The outlet of reactor R2 is connected to the inlet of sampling unit two. The outlet of sampling unit two is connected to buffer tank V1.

[0006] Using the above technical solution, the reaction can be carried out by first mixing and reacting para-ester-hydrochloric acid aqueous solution with sodium nitrite solution, and then treating with aminosulfonic acid slurry. Real-time monitoring through two-stage sampling ensures the stability of the reaction.

[0007] Preferably, the raw material tank T1 stores an aqueous solution of para-ester-hydrochloric acid. A raw material tank T2 is arranged parallel to T1, storing a sodium nitrite solution. The raw materials from both tanks T1 and T2 are fed into reactor R1 after passing through a mixer. Reactor R1 is a dynamic propulsion tubular reactor with an inner diameter of 30 mm and a tube length of 2-3 m. A coolant is introduced into reactor R1 to control the reaction temperature. The reaction products from reactor R1 pass through sampling unit one and then enter reactor R2. Reactor R2 is a pipe-type solid-liquid reactor that receives raw materials from raw material tank T3, which stores aminosulfonic acid slurry. The reaction products from reactor R2 pass through sampling unit two and then enter buffer tank V1, located between reaction sections S1 and S2.

[0008] By adopting the above technical solution, precise mixing of raw materials and temperature control of diazotization reaction can be achieved, ensuring full reaction and elimination of impurities.

[0009] Preferably, the reaction section of module S2 includes reactor R3, which is a pipeline solid-liquid reactor. The inlet end of reactor R3 is connected to buffer tank V1, and the inlet end of reactor R3 is connected to raw material tank T4, which stores H acid slurry.

[0010] By adopting the above technical solution, the H acid slurry and the materials can be mixed and reacted, ensuring that the coupling reaction is complete.

[0011] Preferably, the reaction liquid in reactor R3 enters reactor R4 after passing through sampling unit three. Reactor R4 is a dynamic propulsion tubular reactor. The inner diameter of reactor R1 is 30 mm and the tube length is 2 m-3 m. Cooling medium is introduced into reactor R4 to control the reaction temperature. The reaction liquid in reactor R4 enters buffer tank V2 after passing through sampling unit four. Buffer tank V2 is located between reaction section of module S2 and reaction section of module S3.

[0012] Using the above technical solution, sampling unit three can be used to monitor the reaction within reactor R3. Preferably, the reaction section of module S3 includes reactor R5, which is a pipeline solid-liquid reactor. The inlet end of reactor R5 is connected to raw material tank T5, which stores sodium bicarbonate slurry. The finished product in reactor R5 enters receiving tank V3 for storage after passing through sampling unit five. The outlet end of receiving tank V3 is connected to post-processing unit.

[0013] By adopting the above technical solution, the baking soda slurry can be fully reacted with the materials.

[0014] Preferably, sampling unit one, sampling unit two, sampling unit three, sampling unit four and sampling unit five have the same structure, and each of sampling unit one, sampling unit two, sampling unit three, sampling unit four and sampling unit five constitutes a sampling unit structure.

[0015] By adopting the above technical solution, the product synthesis process can be monitored in stages through the sampling unit structure.

[0016] Preferably, the sampling unit structure includes a main conveying pipe and a sampling branch pipe. The two ends of the main conveying pipe are respectively connected to the composite line pipeline. The sampling branch pipe is C-shaped, and the two ends of the sampling branch pipe are respectively connected to the inside of the main conveying pipe. Valves are respectively provided at the two ends of the sampling branch pipe, and sampling ports are provided on the surface of the sampling branch pipe.

[0017] Using the above technical solution, the reaction solution can be sampled without cutting off the main reaction circuit, thus enabling the location of abnormal reactions.

[0018] Compared with the prior art, the beneficial effects of the present invention are: the continuous synthesis method of active black 5 based on segmented sampling and monitoring: 1. This invention employs a three-stage continuous reaction. Sampling units one through five are set at key nodes in the first, second, and third module reaction sections, namely after reactor R1, reactor R2, reactor R3, reactor R4, and reactor R5, respectively. Each sampling unit is connected to the main synthesis line via a conveying pipe and can extract the reaction liquid at the corresponding stage for status monitoring in real time. When the concentration, pH value, or reaction degree of the reaction liquid is detected to be inconsistent with the preset standard, the abnormal reaction section can be quickly located directly based on the location of the sampling unit. For example, if sampling unit three detects an abnormality, it can pinpoint the mixing process in reactor R3 of the second module reaction section or the supply problem of H acid slurry in raw material tank T4, which facilitates timely adjustment of reaction parameters and avoids the abnormality from expanding and affecting subsequent reactions. 2. In this device, a main conveying pipe is connected to the main synthesis line in the sampling unit, and a C-shaped sampling branch pipe is installed on the surface of the main conveying pipe. The main conveying pipe maintains the continuous flow of the main reaction process. The two ends of the sampling branch pipe are connected to the main pipe and equipped with independent valves. When sampling, only the branch pipe valve needs to be opened to extract the sample from the sampling port without cutting off the main reaction line. This ensures the convenience of sampling operation and avoids the fluctuation of the reaction system caused by the interruption of the reaction. It can make the entire synthesis process continue uninterrupted and shorten the production cycle. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the reaction process structure of the present invention; Figure 2 This is a schematic diagram of the reaction section structure of module one of the present invention; Figure 3 This is a schematic diagram of the reaction section structure of module two of the present invention; Figure 4 This is a schematic diagram of the reaction section structure of module three of the present invention; Figure 5 This is a schematic diagram of the sampling unit structure of the present invention. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Please see Figures 1-5 The present invention provides a technical solution: a continuous synthesis method for active black 5 based on segmented sampling and monitoring.

[0022] The S1 module reaction section includes a mixer. The inlet of the mixer is connected to raw material tanks T1 and T2 via pipes. The outlet of the mixer is connected to reactor R1 via a pipe. The outlet of reactor R1 is connected to the inlet of sampling unit one, and the outlet of sampling unit one is connected to the inlet of reactor R2. The inlet of reactor R2 is connected to raw material tank T3, and the outlet of reactor R2 is connected to the inlet of sampling unit two. The outlet of sampling unit two is connected to buffer tank V1. Raw material tank T1 stores an aqueous solution of para-ester-hydrochloric acid. Raw material tank T2 is arranged parallel to raw material tank T1, and raw material tank T2 stores a sodium nitrite solution. The raw materials in raw material tank T2 are fed into reactor R1 after passing through a mixer. Reactor R1 is a dynamic propulsion tubular reactor with an inner diameter of 30 mm and a tube length of 2-3 m. Cooling medium is introduced into reactor R1 to control the reaction temperature. The reaction products in reactor R1 are fed into reactor R2 after passing through sampling unit one. Reactor R2 is a pipeline solid-liquid reactor. Reactor R2 receives raw materials from raw material tank T3, which stores aminosulfonic acid slurry. The reaction products in reactor R2 are fed into buffer tank V1 after passing through sampling unit two. Buffer tank V1 is located between the reaction section of module S1 and the reaction section of module S2. like Figure 1 , Figure 2 and Figure 5 As shown, raw material tank T1 stores para-ester-hydrochloric acid aqueous solution, raw material tank T2 stores sodium nitrite solution, and raw material tank T3 stores aminosulfonic acid slurry. During the reaction, a diazotization reaction takes place in the reaction section of module one. The discharge pumps of raw material tanks T1 and T2 are started, and the para-ester-hydrochloric acid aqueous solution in raw material tank T1 and the sodium nitrite solution in raw material tank T2 are transported to the mixer. The raw materials are fully mixed in the mixer, and the mixed material is continuously fed into reactor R1. The reaction temperature in reactor R1 is controlled by the introduction of a coolant. The material stays in reactor R1 to carry out the diazotization reaction. After the diazotization reaction, the material flows through the main conveying pipe to sampling unit one. Keeping the main pipe unobstructed, the valves at both ends of the sampling branch pipe are opened to allow the material to flow through the sampling branch pipe. The reaction liquid sample is extracted from the sampling port of the sampling branch pipe. The excess of nitrite in the reaction liquid is detected by potassium iodide-starch test paper. At the same time, the conversion rate of para-ester is detected by high performance liquid chromatography. The conversion rate must reach more than 98% to be considered as qualified for the reaction. If the sampling unit one monitoring is qualified, the material enters reactor R2, the discharge pump of raw material tank T3 is started, and aminosulfonic acid slurry is added into reactor R2. The excess nitrite elimination reaction takes place inside reactor R2. After the material reacts in reactor R2, it is sampled and monitored by sampling unit two. The reaction solution is tested with potassium iodide-starch test paper. If the test paper does not turn blue, the excess nitrite has been completely eliminated. After the test is qualified, the material enters buffer tank V1 for temporary storage.

[0023] The S2 module 2 reaction section includes reactor R3, which is a piped solid-liquid reactor. The inlet of reactor R3 is connected to buffer tank V1 and raw material tank T4, which stores H-acid slurry. The reaction liquid in reactor R3 enters reactor R4 after passing through sampling unit 3. Reactor R4 is a dynamic propulsion tube reactor. The inner diameter of reactor R1 is 30mm and the tube length is 2m-3m. Cooling medium is introduced into reactor R4 to control the reaction temperature. The reaction liquid in reactor R4 enters buffer tank V2 after passing through sampling unit 4. Buffer tank V2 is located between the S2 module 2 reaction section and the S3 module 3 reaction section. The S3 module 3 reaction section includes reactor R5, which is a piped solid-liquid reactor. The inlet of reactor R5 is connected to raw material tank T5, which stores sodium bicarbonate slurry. The finished product in reactor R5 enters receiving tank V3 for storage after passing through sampling unit 5. The outlet of receiving tank V3 is connected to the post-processing unit. like Figure 1 , Figure 3 , Figure 4 and Figure 5 As shown, the first coupling reaction takes place in the reaction section of module S2. The discharge pump of buffer tank V1 is started to transport the product of the reaction section of module I to reactor R3. The discharge pump of raw material tank T4 is started to add H acid slurry into reactor R3. The product of the reaction section of module I and H acid slurry react and mix inside reactor R3 to carry out the first coupling reaction. The reaction solution is sampled and monitored by sampling unit three. The residual amount of H acid in the reaction solution is detected by HPLC. At the same time, the pH value of the reaction solution is detected. If the pH value deviates, it is corrected by adjusting the addition rate of H acid slurry. The reaction solution that meets the monitoring requirements is passed into reactor R4. The reaction temperature is controlled by a coolant. The material stays in reactor R4 to react, ensuring that the first coupling reaction is complete. After the material reacts in reactor R4, it is sampled by sampling unit four. The content of the target intermediate product is detected by HPLC. The qualified material enters buffer tank V2 for temporary storage. In the S3 module reaction section, the second coupling reaction takes place. The discharge pump of buffer tank V2 is started to transport the product of the module reaction section to reactor R5. The discharge pump of raw material tank T5 is started to add baking soda slurry into reactor R5. The baking soda slurry and the product of the module reaction section react in reactor R5 to carry out the second coupling reaction. After the reaction is completed, the material is sampled and monitored by sampling unit five. The finished material that passes the monitoring enters the receiving tank V3 for storage. The finished product is transported to the post-processing unit through the discharge pipe of receiving tank V3 for filtration, drying, pulverization and other processes to obtain the active black 5 finished product.

[0024] Sampling Unit 1, Sampling Unit 2, Sampling Unit 3, Sampling Unit 4, and Sampling Unit 5 have the same structure. Each of these units constitutes a sampling unit structure. Each sampling unit structure includes a main conveying pipe and a sampling branch pipe. The two ends of the main conveying pipe are connected to the composite pipeline. The sampling branch pipe is C-shaped, and both ends of the sampling branch pipe are connected to the inside of the main conveying pipe. Valves are installed at both ends of the sampling branch pipe, and sampling ports are provided on the surface of the sampling branch pipe. like Figure 1 and Figure 5 As shown, when performing the synthesis reaction of Reactive Black 5, the specific operation for sampling the reaction liquid in each sampling unit is as follows: During sampling, it is not necessary to cut off the main reaction line. The main conveying pipe maintains continuous material flow. Open the valves at both ends of the sampling branch pipe to allow material to pass through the sampling branch pipe. Open the sampling port on the surface of the sampling branch pipe to extract the reaction liquid sample. Close the sampling port and close the valves at both ends of the sampling branch pipe to complete the sampling operation. Based on the monitoring results of each sampling unit, the reaction section and cause of the abnormality can be quickly identified. If sampling unit one detects an abnormality, the abnormal reaction section involves the raw material supply of raw material tanks T1 and T2, the mixing effect of the mixer, and reactor R1. If sampling unit two detects an abnormality, the abnormal reaction section involves reactor R2 or raw material tank T3. If sampling unit three detects an abnormality, the abnormal reaction section involves... Normal reaction sections involve reactor R3 or raw material tank T4; if sampling unit four monitors an anomaly, the abnormal reaction section involves reactor R4; if sampling unit five monitors an anomaly, the abnormal reaction section involves reactor R5 and raw material tank T5; each sampling unit corresponds to a specific reaction section, and the abnormal result can directly lock the reaction section without cross-module investigation, shortening the anomaly location time. After locating the cause of the anomaly, the corresponding parameters are adjusted immediately. After adjustment, sampling and monitoring must be carried out again through the same sampling unit until the indicators are qualified, to avoid the anomaly from expanding to subsequent reaction sections. If a sampling unit is abnormal, first confirm whether the monitoring result of the previous sampling unit is qualified. If the previous sampling unit is unqualified, it is a chain reaction, and the preceding anomaly is dealt with first. If the preceding is qualified, the current reaction section is investigated.

[0025] Working principle: In the reaction section of module one, para-ester-hydrochloric acid aqueous solution and sodium nitrite solution are fed into the mixer and mixed. Then, the mixture is fed into reactor R1 for reaction. After the reaction is completed, the reaction liquid is sampled and monitored by sampling unit one. Aminosulfonic acid slurry is added to the reaction liquid. After mixing in reactor R2, the mixture is sampled and monitored by sampling unit two and then enters buffer tank V1 for temporary storage. The material in buffer tank V1 is fed into reactor R3, where H acid slurry is added and mixed. After mixing, the reaction liquid is sampled and monitored by sampling unit three and then fed into reactor R4. After the reaction is completed, the reaction liquid is sampled and monitored by sampling unit four and then enters buffer tank V2 for temporary storage. The material in buffer tank V2 is fed into reactor R5, where sodium bicarbonate slurry is added and mixed. After sampling and monitoring the product status by sampling unit five, the product enters receiving tank V3 and is finally transported to the post-processing unit.

[0026] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention.

Claims

1. A continuous synthesis method for active black 5 based on segmented sampling and monitoring, characterized in that: Includes the following steps: S1, Module 1 Reaction Section: Para-ester-hydrochloric acid aqueous solution and sodium nitrite solution are fed into the mixer and mixed, then fed into reactor R1. After the reaction is completed, the state of the reaction solution is monitored by sampling unit one. Aminosulfonic acid slurry is added to the reaction solution, mixed by reactor R2, and then sampled and monitored by sampling unit two before entering buffer tank V1 for temporary storage. S2, Module 2 Reaction Section: The material in buffer tank V1 is fed into reactor R3, H acid slurry is added and mixed. After mixing, the reaction liquid is sampled by sampling unit three to monitor the state of the reaction liquid, and then fed into reactor R4. After the reaction is completed, the reaction liquid is sampled by sampling unit four to monitor the state of the reaction liquid, and then sent to buffer tank V2 for temporary storage. S3, Module 3 Reaction Section: The material in buffer tank V2 is fed into reactor R5, where sodium bicarbonate slurry is added and mixed. After sampling and monitoring the product status by sampling unit 5, the product enters receiving tank V3 and is finally transported to the post-processing unit.

2. The continuous synthesis method of Reactive Black 5 based on segmented sampling and monitoring according to claim 1, characterized in that: The S1 module reaction section includes a mixer. The inlet of the mixer is connected to raw material tanks T1 and T2 via pipes. The outlet of the mixer is connected to reactor R1 via pipes. The outlet of reactor R1 is connected to the inlet of sampling unit one. The outlet of sampling unit one is connected to the inlet of reactor R2. The inlet of reactor R2 is connected to raw material tank T3. The outlet of reactor R2 is connected to the inlet of sampling unit two. The outlet of sampling unit two is connected to buffer tank V1.

3. The continuous synthesis method of active black 5 based on segmented sampling and monitoring according to claim 2, characterized in that: The raw material tank T1 stores an aqueous solution of para-ester hydrochloric acid. A parallel raw material tank T2 is located next to T1, containing a sodium nitrite solution. The raw materials from both tanks T1 and T2 are fed into reactor R1 after passing through a mixer. Reactor R1 is a dynamic propulsion tubular reactor with an inner diameter of 30 mm and a tube length of 2-3 m. A coolant is introduced into reactor R1 to control the reaction temperature. The reaction products from reactor R1 pass through sampling unit one and then enter reactor R2, a piped solid-liquid reactor. Reactor R2 receives raw materials from raw material tank T3, which stores aminosulfonic acid slurry. The reaction products from reactor R2 pass through sampling unit two and then enter buffer tank V1, located between reaction sections S1 and S2.

4. The continuous synthesis method of active black 5 based on segmented sampling and monitoring according to claim 1, characterized in that: The reaction section of module S2 includes reactor R3, which is a pipeline solid-liquid reactor. The inlet of reactor R3 is connected to buffer tank V1 and raw material tank T4, which stores H acid slurry.

5. The continuous synthesis method of active black 5 based on segmented sampling and monitoring according to claim 4, characterized in that: The reaction liquid in reactor R3 enters reactor R4 after passing through sampling unit three. Reactor R4 is a dynamic propulsion tubular reactor. The inner diameter of reactor R1 is 30mm and the tube length is 2m-3m. Cooling medium is introduced into reactor R4 to control the reaction temperature. The reaction liquid in reactor R4 enters buffer tank V2 after passing through sampling unit four. Buffer tank V2 is located between the reaction section of module S2 and the reaction section of module S3.

6. The continuous synthesis method of Reactive Black 5 based on segmented sampling and monitoring according to claim 1, characterized in that: The reaction section of module S3 includes reactor R5, which is a pipeline solid-liquid reactor. The inlet of reactor R5 is connected to raw material tank T5, which stores sodium bicarbonate slurry. The finished product in reactor R5 enters receiving tank V3 for storage after passing through sampling unit five. The outlet of receiving tank V3 is connected to post-processing unit.

7. The continuous synthesis method of Reactive Black 5 based on segmented sampling and monitoring according to claim 1, characterized in that: Sampling unit 1, sampling unit 2, sampling unit 3, sampling unit 4 and sampling unit 5 have the same structure, and each of them constitutes a sampling unit structure.

8. The continuous synthesis method of Reactive Black 5 based on segmented sampling and monitoring according to claim 1, characterized in that: The sampling unit structure includes a main conveying pipe and a sampling branch pipe. The two ends of the main conveying pipe are respectively connected to the composite line pipeline. The sampling branch pipe is C-shaped, and the two ends of the sampling branch pipe are respectively connected to the inside of the main conveying pipe. Valves are respectively provided at the two ends of the sampling branch pipe, and sampling ports are provided on the surface of the sampling branch pipe.

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