Method for synthesizing high-performance azo pigment through continuous flow

Abstract

The invention belongs to the technical field of pigment synthesis, and particularly relates to a method for synthesizing a high-performance azo pigment through continuous flow, in particular to a method for synthesizing the high-performance azo pigment through a continuous flow production device. The continuous flow production device comprises three pipeline reactors which are sequentially connected in series; the method for synthesizing the high-performance azo pigment through the continuous flow comprises the following steps: S1, carrying out continuous diazotization reaction on a sodium nitrite solution and a diazo component dispersion in a first pipeline reactor; s2, carrying out continuous coupling reaction in a second pipeline reactor; and S3, pigmentation treatment is carried out in the third pipeline reactor. The pipeline reactor is used for continuous synthesis, the pigment product can be directly obtained, an intermediate product storage tank is not needed, and continuous production in the true sense is achieved; the front-section mixing device can ensure the overall mixing effect, and the particle size of the pigment is uniform; the pipeline of the delayed reaction area is enlarged, so that the unit flux is larger, the yield is higher, and the economic benefit is better.

Description

Technical Field

[0001] The present invention belongs to the technical field of pigment synthesis, and particularly relates to a method for continuously synthesizing high-performance azo pigments. Background Art

[0002] Azo pigments are water-insoluble organic compounds containing azo groups in their molecular structures, and are the largest category in terms of variety and output among organic pigments; they have advantages such as bright colors, strong coloring strength, low density, and good light resistance, and are therefore widely used in coatings, rubber, plastics, paper, stationery, and cosmetics.

[0003] The diazotization reaction and the coupling reaction are the most important unit reactions for synthesizing azo pigments and are essential reaction steps in the production of azo pigments. Currently, the diazotization reaction and the coupling reaction are mostly carried out in a traditional batch reactor in the industry; this process is mature and has strong versatility. However, due to the low mass transfer and heat transfer efficiency, heat accumulation will occur in the batch reactor, causing rapid decomposition of diazonium salts; a too long residence time may also cause side reactions such as self-coupling, resulting in poor color properties such as the color shade and coloring strength of the pigment product, and unstable product quality.

[0004] In the continuous production process, since the reaction is continuous and the conditions of the reactants are almost the same, the product properties are stable, which can significantly reduce the batch difference problem and improve the product yield and quality. Wang Fajun et al. (Study on the kinetics of diazotization reaction of red base KD in a microreactor [J]. Journal of Chemical Industry and Engineering (China), 2021, 72(02): 984-992.) theoretically proved the superiority of the microreactor in kinetics by calculating the kinetic parameters of the diazotization reaction of red base KD in the microreactor. Patent CN104479394A provides a continuous preparation method of azo pigments in a branched spiral tube, which uses the efficient mixing of secondary flow generated by the fluid in the spiral tube and the branched structure to change the fluid movement trajectory and increase the mixing effect; however, there is still an interval between each reaction, and it is not a completely continuous process.

[0005] To sum up, although the existing continuous-flow azo pigments have achieved a micron-level dispersion effect in terms of the mixing principle, the unit output is too small. Due to the problem of too narrow internal flux, it can ensure no blockage for pigments with a small solid content, but there is a risk of blockage in the case of high solid content to increase the output. Therefore, large-scale production can only be carried out by means of multiple groups in parallel. For other microreactors, due to reasons such as the process, the flow rates are not related to each other, so buffer tanks or similar devices need to be added between each step to meet the continuity requirements, and they have no advantages in large-scale production. Other technologies have serious disadvantages such as easy blockage, poor mixing effect, and poor mass transfer effect. Summary of the Invention

[0006] In view of the above problems, the present invention provides a method for continuously synthesizing high-performance azo pigments.

[0007] The present invention adopts the following technical solutions:

[0008] A method for continuously synthesizing high-performance azo pigments, using a continuous-flow production device to synthesize the high-performance azo pigments; the continuous-flow production device includes three tubular reactors, and the tubular reactors are connected in series in sequence;

[0009] The method for continuously synthesizing high-performance azo pigments includes: S1. Continuously performing a diazotization reaction of a sodium nitrite solution and a diazo component dispersion in a first tubular reactor; S2. Continuously performing a coupling reaction in a second tubular reactor; S3. Performing a pigmentation treatment in a third tubular reactor;

[0010] Wherein, the tubular reactor includes a mixing device at the front stage and a delay reaction zone at the rear stage; the mixing device is a spiral backflow groove; the mixing device includes at least two feeding ports.

[0011] Preferably, S2 is continuously reacted on the premise that S1 is uninterrupted, and S3 is continuously reacted on the premise that S1 and S2 are uninterrupted.

[0012] Preferably, the specific steps of S1 are as follows:

[0013] S101. Prepare a sodium nitrite solution: Dissolve sodium nitrite solid in water and stir evenly;

[0014] S102. Prepare a diazo component dispersion: Add a diazo component, hydrochloric acid, and glacial acetic acid to water at room temperature and stir evenly;

[0015] S103. Diazotization reaction: Simultaneously and continuously transport the sodium nitrite solution and the diazo component dispersion to the first tubular reactor, disperse and mix them evenly in the first mixing device, and perform a diazotization reaction in the first delay reaction zone to obtain diazo liquid A.

[0016] Glacial acetic acid is a weak acid, which can play a buffering role in the subsequent coupling reaction, making the coupling pH value easier to control, the distribution narrower, and the particle size distribution of the product more uniform.

[0017] Preferably, in S103, the feeding speed of the sodium nitrite solution is 10-30 mL / min, the feeding speed of the diazo component dispersion is 40-120 mL / min; the reaction temperature is -5°C to 20°C, and the residence time in the delay reaction zone is 200 s to 600 s.

[0018] Preferably, in the step S102, the diazo component accounts for 3% - 5% of the total mass of the diazo component dispersion, hydrochloric acid accounts for 5% - 9% of the total mass of the diazo component dispersion, and glacial acetic acid accounts for 2% - 4% of the total mass of the diazo component dispersion; in the step S103, in terms of molar ratio, diazo component: sodium nitrite = 1:1.0 - 1.1.

[0019] Preferably, the specific steps of the step S2 are as follows:

[0020] S201. Prepare the coupling component solution: Dissolve sodium hydroxide in water, add the coupling component at 90°C, stir until dissolved and clear, cool down to room temperature, and filter;

[0021] S202. Coupling reaction: Continuously convey the diazo solution A and the coupling component solution to the second pipeline reactor at the same time, disperse and mix them evenly in the second mixing device, and carry out the coupling reaction in the second delay reaction zone to obtain the crude pigment.

[0022] Preferably, in the step S201, the coupling component accounts for 4% - 6% of the total mass of the coupling component solution; in terms of molar ratio, coupling component: sodium hydroxide = 1:2.

[0023] Preferably, in the step S202, the conveying speed is 60 - 120 mL / min; in terms of molar ratio, coupling component: diazo component = 1:1; the reaction temperature is 25 - 60°C, and the residence time in the delay reaction zone is 2 - 5 min.

[0024] Preferably, the specific steps of the step S3 are as follows:

[0025] Continuously feed the crude pigment into the third pipeline reactor, disperse and mix it evenly in the third mixing device, and carry out the pigmentation reaction in the third delay reaction zone to obtain the high-performance azo pigment;

[0026] Among them, after the two-step reactions of S1 and S2, the pH of the pigment slurry entering the third pipeline is 2 - 5, the reaction temperature is 20 - 90°C, and the residence time in the delay reaction zone is 2.5 - 5 min.

[0027] Preferably, the continuous flow production device further includes a diazo component dispersion storage tank and a diazo component dispersion feed pump, a sodium nitrite solution storage tank and a sodium nitrite solution feed pump, and a coupling component solution storage tank and a coupling component solution feed pump;

[0028] The diazo component dispersion storage tank is fed into the first mixing device at the front section of the first pipeline reactor through the diazo component dispersion feed pump, and the sodium nitrite component solution storage tank is fed into the first mixing device at the front section of the first pipeline reactor through the sodium nitrite solution feed pump;

[0029] The first delay reaction zone at the rear section of the first pipeline reactor is connected to the second mixing device at the front section of the second pipeline reactor; the coupling component solution storage tank is connected to the second mixing device at the front section of the second pipeline reactor through a coupling component solution feed pump;

[0030] The second delay reaction zone at the rear section of the second pipeline reactor is connected to the third mixing device at the front section of the third pipeline reactor;

[0031] The third delay reaction zone at the rear section of the third pipeline reactor is connected to the pigment product storage tank.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] (1) The present invention uses a pipeline reactor to replace the traditional batch reactor, realizing the continuous synthesis of azo pigments; compared with other microchannel reactors, there is no risk of blockage, and the enlargement of the pipeline in the delay reaction zone enables a larger unit flux, higher yield, and better economic benefits;

[0034] (2) In the pigment synthesis process of the present invention, a pipeline reactor is adopted. Through efficient heat exchange and stable control of process parameters, the purity and selectivity of the product are improved. The pigment product has a smaller particle size, more concentrated distribution, better performance, and more stable quality;

[0035] (3) Compared with the traditional batch reaction, the pipeline reactor used in the present invention greatly shortens the total time for producing pigments per unit output, improving production efficiency; it reduces wastewater discharge from the production source, has a low comprehensive energy consumption, and is environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a schematic structural diagram of the continuous flow production device of the present invention;

[0037] Description of the reference numerals:

[0038] 1. Diazo component dispersion storage tank; 11. Diazo component dispersion feed pump; 2. Sodium nitrite solution storage tank; 21. Sodium nitrite solution feed pump; 3. Coupling component solution storage tank; 31. Coupling component solution feed pump; 4. First pipeline reactor; 41. First mixing device; 42. First delay reaction zone; 5. Second pipeline reactor; 51. Second mixing device; 52. Second delay reaction zone; 6. Third pipeline reactor; 61. Third mixing device; 62. Third delay reaction zone; 7. Pigment product storage tank. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] The following will further elaborate on the continuous preparation method described in the present invention in combination with specific embodiments and drawings to help those skilled in the art have a more complete, accurate, and in-depth understanding of the inventive concept and technical solution of the present invention.

[0040] Example 1 Continuous Flow Production Device

[0041] As Figure 1 shown, a continuous flow production device includes a first tubular reactor 4, a second tubular reactor 5, and a third tubular reactor 6, and the three tubular reactors are connected in series in sequence;

[0042] Among them, the tubular reactor includes a mixing device in the front section and a delayed reaction zone in the rear section; the mixing device is a spiral reverse flow tank; the mixing device includes at least two feeding ports.

[0043] The continuous flow production device further includes a diazo component dispersion storage tank 1 and a diazo component dispersion feed pump 11, a sodium nitrite solution storage tank 2 and a sodium nitrite solution feed pump 21, and a coupling component solution storage tank 3 and a coupling component solution feed pump 31;

[0044] The diazo component dispersion storage tank 1 is introduced into the first mixing device 41 in the front section of the first tubular reactor 4 through the diazo component dispersion feed pump 11, and the sodium nitrite solution storage tank 2 is introduced into the first mixing device 41 in the front section of the first tubular reactor 4 through the sodium nitrite solution feed pump 21;

[0045] The first delayed reaction zone 42 in the rear section of the first tubular reactor 4 is introduced into the second mixing device 51 in the front section of the second tubular reactor 5; the coupling component solution storage tank 3 is introduced into the second mixing device 51 in the front section of the second tubular reactor 5 through the coupling component solution feed pump 31;

[0046] The second delayed reaction zone 52 in the rear section of the second tubular reactor 5 is introduced into the third mixing device 61 in the front section of the third tubular reactor 6;

[0047] The third delayed reaction zone 62 in the rear section of the third tubular reactor 6 is introduced into the pigment product storage tank 7.

[0048] Example 2

[0049] Taking the pigment red 146 product as an example, the above device is used for the synthesis of azo pigments.

[0050] S101. Prepare a sodium nitrite solution: Dissolve 12.6 g of sodium nitrite solid in 400 mL of water and stir evenly;

[0051] S102. Prepare a diazo component dispersion: Add 52 g of red base KD, 91.2 g of hydrochloric acid (30%), and 41.6 g of glacial acetic acid to water at room temperature, adjust the volume to 1600 mL, and stir evenly;

[0052] S103, Diazotization reaction: The sodium nitrite solution is continuously fed into the first pipe reactor at a rate of 20 mL / min, and the diazo component dispersion is continuously fed into the first pipe reactor at a rate of 80 mL / min. They are dispersed and mixed evenly in the first mixing device, and the diazotization reaction is carried out in the first delay reaction zone. The temperature is controlled at 0 °C and the residence time is 200 s to obtain diazo solution A.

[0053] S201, Preparation of coupling component solution: Dissolve 19 g of sodium hydroxide (96%) in 1500 mL of water, heat to 90 °C, add 78.4 g of naphthol AS-LC, adjust the volume to 2000 mL, stir evenly, cool to room temperature, and filter.

[0054] S202, Coupling reaction: The diazo solution A and the coupling component solution are continuously fed into the second pipe reactor at a rate of 100 mL / min. They are dispersed and mixed evenly in the second mixing device, and the coupling reaction is carried out in the second delay reaction zone. The temperature is controlled at 25 °C and the residence time is 2.5 min to obtain the crude pigment.

[0055] S3, Pigmentization reaction: The crude pigment is continuously fed into the third pipe reactor, dispersed and mixed evenly in the third mixing device, and the pigmentization reaction is carried out in the third delay reaction zone. The temperature is controlled at 20 °C and the residence time is 2.5 min for crystal transformation. Then, it is filtered, washed with water, and dried to obtain the high-performance azo pigment.

[0056] Example 3

[0057] S101, Preparation of sodium nitrite solution: Dissolve 12.6 g of sodium nitrite solid in 400 mL of water and stir evenly.

[0058] S102, Preparation of diazo component dispersion: Add 52 g of red base KD, 91.2 g of hydrochloric acid (30%), and 41.6 g of glacial acetic acid to water at room temperature, adjust the volume to 1600 mL, and stir evenly.

[0059] S103, Diazotization reaction: The sodium nitrite solution is continuously fed into the first pipe reactor at a rate of 10 mL / min, and the diazo component dispersion is continuously fed into the first pipe reactor at a rate of 40 mL / min. They are dispersed and mixed evenly in the first mixing device, and the diazotization reaction is carried out in the first delay reaction zone. The temperature is controlled at -5 °C and the residence time is 500 s to obtain diazo solution A.

[0060] S201, Preparation of coupling component solution: Dissolve 19 g of sodium hydroxide (96%) in 1500 mL of water, heat to 90 °C, add 78.4 g of naphthol AS-LC, adjust the volume to 2000 mL, stir evenly, cool to room temperature, and filter.

[0061] S202, Coupling reaction: Continuously convey the diazo solution A and the coupling component solution to the second pipeline reactor at a speed of 100 mL / min simultaneously, disperse and mix them evenly in the second mixing device, conduct the coupling reaction in the second delay reaction zone, control the temperature at 30 °C, and keep for 2 min to obtain the crude pigment;

[0062] S3, Pigmentization reaction: Continuously feed the crude pigment into the third pipeline reactor, disperse and mix it evenly in the third mixing device, conduct the pigmentization reaction in the third delay reaction zone, control the temperature at 40 °C, keep for 5 min for crystal transformation, filter, wash with water, and dry to obtain the high-performance azo pigment.

[0063] Example 4

[0064] S101, Prepare sodium nitrite solution; Dissolve 12.6 g of sodium nitrite solid in 400 mL of water and stir evenly;

[0065] S102, Prepare the diazo component dispersion: Add 52 g of red base KD, 91.2 g of hydrochloric acid (30%), and 41.6 g of glacial acetic acid to water at room temperature, adjust the volume to 1600 mL, and stir evenly;

[0066] S103, Diazotization reaction: Continuously convey the sodium nitrite solution at a speed of 20 mL / min and the diazo component dispersion at a speed of 80 mL / min to the first pipeline reactor simultaneously, disperse and mix them evenly in the first mixing device, conduct the diazotization reaction in the first delay reaction zone, control the temperature at 5 °C, and keep for 300 s to obtain the diazo solution A;

[0067] S201, Prepare the coupling component solution: Dissolve 19 g of sodium hydroxide (96%) in 1500 mL of water, heat to 90 °C, add 78.4 g of naphthol AS-LC, adjust the volume to 2000 mL, stir evenly, cool to room temperature, and filter;

[0068] S202, Coupling reaction: Continuously convey the diazo solution A and the coupling component solution to the second pipeline reactor at a speed of 60 mL / min simultaneously, disperse and mix them evenly in the second mixing device, conduct the coupling reaction in the second delay reaction zone, control the temperature at 40 °C, and keep for 3 min to obtain the crude pigment;

[0069] S3, Pigmentization reaction: Continuously feed the crude pigment into the third pipeline reactor, disperse and mix it evenly in the third mixing device, conduct the pigmentization reaction in the third delay reaction zone, control the temperature at 60 °C, keep for 2.5 min for crystal transformation, filter, wash with water, and dry to obtain the high-performance azo pigment.

[0070] Example 5

[0071] S101, Prepare sodium nitrite solution; Dissolve 18.90 g of sodium nitrite solid in 400 mL of water and stir evenly;

[0072] S102. Preparation of diazo component dispersion: Add 78 g of Red Base KD, 136.8 g of hydrochloric acid (30%), and 62.4 g of glacial acetic acid to water at room temperature, adjust the volume to 1600 mL, and stir evenly.

[0073] S103. Diazotization reaction: Continuously convey the sodium nitrite solution and the diazo component dispersion to the first pipe reactor at speeds of 20 mL / min and 80 mL / min respectively, disperse and mix them evenly in the first mixing device, carry out the diazotization reaction in the first delayed reaction zone, control the temperature at 10°C, and keep for 600 s to obtain diazo solution A.

[0074] S201. Preparation of coupling component solution: Dissolve 28.5 g of sodium hydroxide (96%) in 1500 mL of water, heat to 90°C, add 117.6 g of Naphthol AS-LC, adjust the volume to 2000 mL, stir evenly, cool to room temperature, and filter.

[0075] S202. Coupling reaction: Continuously convey diazo solution A and the coupling component solution to the second pipe reactor at a speed of 120 mL / min, disperse and mix them evenly in the second mixing device, carry out the coupling reaction in the second delayed reaction zone, control the temperature at 55°C, and keep for 4 min to obtain crude pigment.

[0076] S3. Pigmentation reaction: Continuously feed the crude pigment into the third pipe reactor, disperse and mix it evenly in the third mixing device, carry out the pigmentation reaction in the third delayed reaction zone, control the temperature at 80°C, keep for 5 min for crystal conversion, filter, wash with water, and dry to obtain high-performance azo pigment.

[0077] Example 6

[0078] S101. Preparation of sodium nitrite solution: Dissolve 12.6 g of sodium nitrite solid in 400 mL of water and stir evenly.

[0079] S102. Preparation of diazo component dispersion: Add 52 g of Red Base KD, 91.2 g of hydrochloric acid (30%), and 41.6 g of glacial acetic acid to water at room temperature, adjust the volume to 1600 mL, and stir evenly.

[0080] S103. Diazotization reaction: Continuously convey the sodium nitrite solution and the diazo component dispersion to the first pipe reactor at speeds of 30 mL / min and 120 mL / min respectively, disperse and mix them evenly in the first mixing device, carry out the diazotization reaction in the first delayed reaction zone, control the temperature at 20°C, and keep for 450 s to obtain diazo solution A.

[0081] S201. Preparation of coupling component solution: Dissolve 19 g of sodium hydroxide (96%) in 1500 mL of water, heat to 90 °C, add 78.4 g of naphthol AS-LC, adjust the volume to 2000 mL, stir evenly, cool to room temperature, and filter;

[0082] S202. Coupling reaction: Continuously transport the diazo solution A and the coupling component solution to the second pipeline reactor at a speed of 120 mL / min, disperse and mix them evenly in the second mixing device, carry out the coupling reaction in the second delayed reaction zone, control the temperature at 60 °C, and stay for 5 min to obtain the crude pigment;

[0083] S3. Pigmentization reaction: Continuously feed the crude pigment into the third pipeline reactor, disperse and mix it evenly in the third mixing device, carry out the pigmentization reaction in the third delayed reaction zone, control the temperature at 90 °C, stay for 5 min for crystal conversion, filter, wash with water, and dry to obtain the high-performance azo pigment.

[0084] Comparative Example 1 Preparation of Pigment Red 146 by Batch Reaction

[0085] Add 1.5 m of water to the diazo tank 3 , add 213 kg of hydrochloric acid, 162.5 kg of red base KD, 140 kg of acetic acid, stir for 10 min, add ice to cool down to 5 °C, add 144 kg of sodium nitrite solution (30.5%, w / w), stir and react for 60 minutes, add an appropriate amount of sulfamic acid to obtain the diazo solution; in the coupling tank, add 1.8 m of water 3 , 175.5 kg of liquid caustic soda (23%, w / w), 3.9 kg of Auxiliary A, heat up to 95 °C, add 247.5 kg of naphthol AS-LC, stir for 10 min, add ice to cool down to 50 °C to obtain the coupling component solution; transfer the diazo solution to the coupling tank in 30 min, after coupling, the temperature is 25 °C, pH = 4, stir for 60 min, add Auxiliary B, heat up to 85 °C, keep warm for 30 min, add water to cool down to 65 °C, filter under pressure, wash with water, and dry to obtain Pigment Red 146.

[0086] The products obtained in Examples 2 to 6 and Comparative Example 1 were subjected to polyurethane-based solvent ink application tests, and the results are shown in Table 1.

[0087] Table 1 Test Results of Product Performance

[0088] Product Color strength Transparency Viscosity Glossiness D(50) Example 2 140％ Grade 5 45.24 cp 17.3 209 nm Example 3 118％ Grade 4 43.28 cp 14.9 247 nm Example 4 129％ Grade 4 44.67 cp 14.1 276 nm Example 5 123％ Grade 4 50.12 cp 13.4 246 nm Example 6 133％ Grade 5 44.32 cp 18.1 212 nm Comparative Example 1 100％ Grade 1 60.32 cp 0 392 nm

[0089] * Transparency data, graded from 1 to 5 levels, with 1 level having the worst transparency and 5 levels having the highest transparency.

[0090] It can be found from the comparison between Examples 2 to 6 and Comparative Example 1 that the azo pigment products synthesized by continuous flow in a pipe reactor are applied to the polyurethane ink system, with a coloring strength of 118-140%, high transparency, and the viscosity is reduced by 25-45% compared to Comparative Example 1, and the performance is excellent.

[0091] The above embodiments are intended to illustrate the embodiments disclosed in the present invention and should not be construed as limiting the present invention. In addition, various modifications listed herein and changes in the methods and compositions of the invention will be apparent to those skilled in the art without departing from the scope and spirit of the present invention. Although the present invention has been specifically described in conjunction with various specific preferred embodiments of the present invention, it should be understood that the present invention should not be limited to these specific embodiments. In fact, all obvious modifications to those skilled in the art as described above to obtain the invention should be included within the scope of the present invention.

Claims

1. A method for continuously synthesizing high-performance azo pigments, characterized in that, Synthesize the high-performance azo pigment using a continuous flow production device; the continuous flow production device includes three tubular reactors, which are connected in series in sequence; The method for continuously synthesizing the high-performance azo pigment includes: S1. Conduct a continuous diazotization reaction of a sodium nitrite solution and a diazo component dispersion in a first tubular reactor; S2. Conduct a continuous coupling reaction in a second tubular reactor; S3. Conduct a pigmentation treatment in a third tubular reactor; Among them, the tubular reactor includes a premixing device in the front section and a delay reaction zone in the rear section.

2. The method for continuously synthesizing high-performance azo pigments according to claim 1, characterized in that, S2 is a continuous reaction on the premise that S1 is uninterrupted, and S3 is a continuous reaction on the premise that S1 and S2 are uninterrupted.

3. The method for continuously synthesizing high-performance azo pigments according to claim 1, characterized in that, The specific steps of S1 are as follows: Simultaneously and continuously transport the sodium nitrite solution and the diazo component dispersion to the first tubular reactor, disperse and mix them evenly in the first premixing device, conduct a diazotization reaction in the first delay reaction zone to obtain diazo liquid A, the reaction temperature is -5°C to 20°C, and the residence time in the delay reaction zone is 200 s to 600 s.

4. The method for continuously synthesizing high-performance azo pigments according to claim 3, characterized in that, The feeding rate of the sodium nitrite solution is 10 - 30 mL / min, and the feeding rate of the diazo component dispersion is 40 - 120 mL / min.

5. The method for continuously synthesizing high-performance azo pigments according to claim 3, characterized in that, The preparation method of the diazo component dispersion is: Add the diazo component, hydrochloric acid, and glacial acetic acid into water at room temperature and stir evenly; among them, the diazo component accounts for 3% - 5% of the total mass of the diazo component dispersion, hydrochloric acid accounts for 5% - 9% of the total mass of the diazo component dispersion, and glacial acetic acid accounts for 2% - 4% of the total mass of the diazo component dispersion.

6. The method for continuously synthesizing a high-performance azo pigment according to claim 1, characterized in that, The specific steps of S2 are as follows: Simultaneously and continuously transport diazo liquid A and a coupling component solution to the second tubular reactor, disperse and mix them evenly in the second premixing device, conduct a coupling reaction in the second delay reaction zone to obtain a crude pigment, the reaction temperature is 25 - 60°C, and the residence time in the delay reaction zone is 2 - 5 min.

7. The method for continuously synthesizing a high-performance azo pigment according to claim 6, characterized in that, The feeding rate of the coupling component solution is 60 - 120 mL / min.

8. The method for continuously synthesizing a high-performance azo pigment according to claim 6, characterized in that, The coupling component accounts for 4% - 6% of the total mass of the coupling component solution.

9. The method for continuously synthesizing high-performance azo pigments according to claim 1, characterized in that, The specific steps of S3 are as follows: Continuously feed the crude pigment into the third tubular reactor, disperse and mix it evenly in the third premixing device, conduct a pigmentation reaction in the third delay reaction zone to obtain a high-performance azo pigment; among them, the reaction temperature is 20 - 90°C, and the residence time in the delay reaction zone is 2.5 - 5 min.

10. The method for continuously synthesizing high-performance azo pigments according to claim 1, characterized in that, The continuous flow production device further includes a diazo component dispersion storage tank (1) and a diazo component dispersion feeding pump (11), a sodium nitrite solution storage tank (2) and a sodium nitrite solution feeding pump (21), and a coupling component solution storage tank (3) and a coupling component solution feeding pump (31); The diazo component dispersion storage tank (1) is fed into the first premixing device (41) at the front section of the first tubular reactor (4) through the diazo component dispersion feeding pump (11), and the sodium nitrite solution storage tank (2) is fed into the first premixing device (41) at the front section of the first tubular reactor (4) through the sodium nitrite solution feeding pump (21); The first delay reaction zone (42) at the rear stage of the first pipeline reactor (4) is introduced into the second mixing device (51) at the front stage of the second pipeline reactor (5); The coupling component solution storage tank (3) is introduced into the second mixing device (51) at the front stage of the second pipeline reactor (5) through the coupling component solution feed pump (31); The second delay reaction zone (52) at the rear stage of the second pipeline reactor (5) is introduced into the third mixing device (61) at the front stage of the third pipeline reactor (6); The third delay reaction zone (62) at the rear stage of the third pipeline reactor (6) is introduced into the pigment product storage tank (7).

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