An automatic continuous production process and synthesis system for liquid azo dyes

Abstract

The present invention discloses a production process and a synthesis system for automatic continuous liquid azo dyes, belonging to the field of azo dye synthesis. In this production process, a diazo component is added, the first circulation temperature control device is started, nitrite is added, and the first circulation temperature control device circulates the materials and controls the temperature; the diazo component and nitrite are continuously added; the diazo discharge valve is opened, and the diazo reaction liquid flows out; the first feed pump and the second feed pump are turned on, and at the same time, the second circulation temperature control device and the third circulation temperature control device are started; the mixed liquid of the diazo reaction liquid and the dispersant continuously sprays out from the first nozzle, and at the same time, the mixed liquid of the coupling component and the dispersant continuously sprays out from the second nozzle, and the first nozzle and the second nozzle spray against each other; both the second circulation temperature control device and the third circulation temperature control device are used to circulate the materials in the coupling reaction device and control the coupling reaction temperature; the coupling discharge valve is opened to obtain liquid dyes. The present invention can continuously produce azo dyes.

Description

Technical Field

[0001] The present invention belongs to the field of azo dye synthesis, and particularly relates to a production process and a synthesis system for automatic continuous liquid azo dyes. Background Art

[0002] In the molecular structure of azo dyes, usually more than one azo group structure is connected to an aryl group.

[0003] Most commercial dyes are powder dyes. In the last process of dye preparation, a large amount of additives need to be added, and then dried by high-temperature gas in a spray drying tower (abbreviation: spray tower). Therefore, there are a large amount of spray tower exhaust gases in this process. The main components are residual methylnaphthalene, naphthalene derivatives and other organic pollutants in the dispersant. Due to the large volume of the spray tower exhaust gas, the air volume of a single spray tower with a diameter of 8 meters generally exceeds 100,000 m 3 / h, and the exhaust gas has high humidity and strong odor, which is difficult to treat and has a serious impact on the environment.

[0004] All azo dyes are obtained by reacting an aromatic amine compound with nitrous acid (since nitrous acid is unstable, sodium nitrite or nitrosylsulfuric acid is actually used in industry) under acidic conditions to obtain a diazonium salt, and then coupling with a coupling component (aromatic phenol, amine or an active methylene compound).

[0005] The diazotization reaction is a dangerous chemical reaction. The reaction releases heat instantaneously, and the product is easily decomposed. If a traditional kettle-type device is used, a large amount of ice needs to be consumed. On the one hand, this ice is used to offset the reaction heat, on the other hand, it consumes the ambient temperature and the mechanical temperature rise brought by strong mechanical stirring. At the same time, since the diazonium salt product also needs to be stored at low temperature safely and the storage time is relatively long, the energy consumption is very large, the waste is very large, and the product quality is unstable and the yield fluctuates greatly.

[0006] Compared with the diazotization reaction, the coupling reaction rate is slower, and the solubility of the reaction product often changes greatly. Especially for some coupling components of azo disperse dyes, their solubility in water is very low, and they are prone to precipitation, resulting in a significant increase in the viscosity of the material, seriously affecting the mixing of the material, and easily forming material wrapping, causing incomplete reaction. At the same time, the intermediate diazonium salt of azo dyes is very unstable. In order to improve the yield, strict reaction conditions need to be controlled during the synthesis of azo dyes. The diazonium salt and the coupling component need to be mixed and collided within a short time for electrophilic substitution reaction, and it is necessary to ensure rapid completion at low temperature. Most of the coupling reactions in industrial production adopt batch kettle operation. To control the reaction temperature, jacket heat removal is generally used. For reactions with strict temperature requirements, it is necessary to pass chilled brine into the kettle through a coiled pipe for cooling, supplemented by high-speed stirring. The coupling reaction proceeds slowly at low temperature, and batch reactions all require a long residence time. Moreover, even if the methods of jacket heat removal and heat removal by salt ice coiled pipe in the kettle are adopted, it is still impossible to avoid local overheating in the kettle, which causes side reactions such as diazonium salt decomposition and self-coupling, reducing the product yield and affecting the dye quality. Therefore, the traditional batch kettle reaction has defects such as long residence time, high energy consumption, low product yield, large space consumption, and unstable quality between batches.

[0007] Patent CN201410436889.8 discloses a continuous production device for azo disperse dyes, which adopts a tubular reactor and adds a propeller-type feeding agitator and a propeller-type discharging agitator for combined operation to ensure that the tubular reactor can realize the continuous production of azo disperse dyes.

[0008] Patent CN201711476722.4 discloses a continuous coupling process for azo disperse dyes with ester groups. This invention improves the coupling temperature of the coupling component compound that is prone to hydrolysis under acidic conditions by stepwise continuous improvement of the traditional batch coupling reaction process. While reducing the dependence on refrigerant, it greatly shortens the coupling reaction time, reduces the hydrolysis of the coupling component, and improves the product yield and production efficiency.

[0009] Patent CN201711273474.3 discloses a continuous production device and production method for azo dye coupling reaction. This invention designs a tower reactor, which can greatly improve the reaction rate between the coupling component and the diazo component, and at the same time transfer the reaction heat out in time. The tower reactor can effectively avoid backmixing of the liquid material, realize the continuous coupling reaction of azo dyes, strengthen the mass transfer between the coupling and diazo components, and greatly reduce the generation of wastewater volume.

[0010] The above continuous research on azo dyes has played a certain role in promoting the industrial synthesis of azo dyes. However, there are still disadvantages such as complex process, difficult control, and complex reactor structure. Therefore, it is imperative to develop an automated continuous production preparation system for liquid azo dyes. Summary of the Invention

[0011] The first object of the present invention is to provide a production process for automatic continuous liquid azo dyes in view of the above problems existing in the prior art; the second object of the present invention is to provide a synthesis system for realizing the above production process of automatic continuous liquid azo dyes.

[0012] The first object of the present invention can be achieved by the following technical solutions: A production process for automatic continuous liquid azo dyes, characterized by comprising the following steps:

[0013] S01: Add a diazo component to the diazo reaction device, turn on the first circulation temperature control device, and then add nitrite to the diazo reaction device. The first circulation temperature control device circulates the materials in the diazo reaction device and controls the diazo reaction temperature;

[0014] S02: Continuously add a diazo component and nitrite to the diazo reaction device; open the diazo discharge valve, and the diazo reaction liquid flows out;

[0015] S03: Turn on the first feed pump and the second feed pump, and at the same time turn on the second circulation temperature control device and the third circulation temperature control device. The diazo reaction liquid and the dispersant are mixed before entering the first feed pump, and the coupling component and the dispersant are mixed before entering the second feed pump;

[0016] The mixed liquid of the diazo reaction liquid and the dispersant continuously sprays out from the first nozzle of the coupling reaction device. At the same time, the mixed liquid of the coupling component and the dispersant continuously sprays out from the second nozzle of the coupling reaction device, and the first nozzle and the second nozzle spray against each other; the second circulation temperature control device and the third circulation temperature control device are both used to circulate the materials in the coupling reaction device and control the coupling reaction temperature;

[0017] S04: Open the coupling discharge valve to obtain a liquid dye.

[0018] Preferably, in step S03, the second circulation temperature control device mixes the materials in the coupling reaction device with the diazo reaction liquid and the dispersant and sprays them out from the first nozzle, and the third circulation temperature control device mixes the materials in the coupling reaction device with the coupling component and the dispersant and sprays them out from the second nozzle.

[0019] Preferably, in step S02, when the potential of the materials in the diazo reaction device reaches a preset value, the diazo discharge valve automatically opens; in step S04, when the potential of the materials in the coupling reaction device reaches a preset value, the coupling discharge valve automatically opens.

[0020] Preferably, in step S03, the diazo reaction liquid and the dispersant are mixed, and the amount of the dispersant is 40-50% of the feed amount of the diazo reaction liquid; the coupling combination and the dispersant are mixed, and the amount of the dispersant is 20% of the feed amount of the coupling component.

[0021] Preferably, the coupling reaction device has six outlets, with an angular interval of 60° between each two outlets. The two outlets facing each other are combined into one stream and flow into the second circulation temperature control device, the third circulation temperature control device, and the coupling discharge valve respectively.

[0022] The second object of the present invention can be achieved by the following technical solution: a synthesis system for realizing the above-mentioned automatic continuous production process of liquid azo dyes, characterized in that it includes a diazotization reaction device and a coupling reaction device. The diazotization reaction device is connected with a diazo component feeding device and a nitrite feeding device. The coupling reaction device includes a first nozzle and a second nozzle, which are arranged opposite to each other. Both the first nozzle and the second nozzle are connected with a dispersant feeding device. The diazotization reaction device is connected with the first nozzle, and the second nozzle is also connected with a coupling component feeding device. The first nozzle is used to spray a mixture of a dispersant and a diazotization reaction liquid, and the second nozzle is used to spray a mixture of a dispersant and a coupling component. The coupling reaction device is connected with a liquid dye storage device for storing the generated dye.

[0023] Preferably, the diazotization reaction device is provided with a first circulation temperature control device, and the coupling reaction device is provided with a second circulation temperature control device and a third circulation temperature control device. The first circulation temperature control device, the second circulation temperature control device, and the third circulation temperature control device all include a circulation pipeline and a heat exchanger arranged on the circulation pipeline. The second circulation temperature control device is used to circulate the materials in the coupling reaction device from the first nozzle into the coupling reaction device, and the third circulation temperature control device is used to circulate the materials in the coupling reaction device from the second nozzle into the coupling reaction device. Both the second circulation temperature control device and the third circulation temperature control device are used to control the temperature of the coupling reaction. The first circulation temperature control device is used to circulate the materials in the diazotization reaction device and control the temperature of the diazotization reaction. One end of the heat exchanger is for the entry of the refrigerant, and the other end of the heat exchanger is for the outflow of the refrigerant. The heat exchanger is used for heat exchange between the refrigerant and the materials, and the heat exchanger and the circulation pipeline are detachably connected.

[0024] Preferably, the diazotization reaction device includes a diazotization reactor. A third nozzle is arranged at the top of the diazotization reactor. One end of the circulation pipeline of the first circulation temperature control device is connected to the bottom of the diazotization reactor, and the other end of the circulation pipeline of the first circulation temperature control device is immersed in the materials inside the diazotization reactor from the top of the diazotization reactor. The third nozzle is located in the circulation pipeline of the first circulation temperature control device. A diazotization circulation pump is arranged on the circulation pipeline of the first circulation temperature control device. The nitrite feeding device is connected to the circulation pipeline of the first circulation temperature control device.

[0025] Preferably, a diazo intermediate tank is provided between the diazo reaction device and the coupling reaction device, a diazo discharge valve is provided between the diazo intermediate tank and the diazo reaction device, the liquid dye storage device and the coupling reaction device are connected through a discharge pipeline, a coupling discharge valve is provided on the discharge pipeline, the coupling reactor and the diazotization reactor are both provided with a potentiometer for detecting the potential, the potentiometer is communicatively connected to a control device, the potentiometer is used to transmit the detected potential information to the control device, and the control device controls the opening or closing of the diazo discharge valve and the coupling discharge valve, as well as the opening size of the diazo discharge valve and the coupling discharge valve according to the potential information.

[0026] Preferably, the coupling reaction device includes a tubular coupling reactor and a draft tube arranged inside the coupling reactor, and the first spray head and the second spray head are located at both ends of the draft tube; 6 outlets are evenly distributed in the middle of the coupling reactor, and the interval angle of each outlet is 60°, and the two directly opposite outlets are respectively communicated with the second circulation temperature control device, the third circulation temperature control device and the discharge pipeline through pipelines.

[0027] Preferably, the first spray head is connected to a first feed pump, the second spray head is connected to a second feed pump, the first feed pump is used to pump the mixed liquid of the material, diazo reaction liquid and dispersant in the coupling reaction device into the first spray head, and the second feed pump is used to pump the mixed liquid of the material, coupling component and dispersant in the coupling reaction device into the second spray head.

[0028] The working principle of the present invention: The present invention includes continuous diazotization reaction and continuous coupling reaction. In the continuous diazotization reaction, a certain amount of diazo component is first added, and the first circulation temperature control device is started at the same time, and then a certain amount of nitrite is added; when the addition of nitrite is completed, the diazo component and nitrite are continuously added to the diazotization reaction device in a preset ratio to carry out continuous diazotization reaction. When the potential of the material in the diazo reaction device reaches the preset value, the diazo discharge valve automatically opens, and the diazo reaction liquid enters the next continuous coupling reaction.

[0029] In the continuous coupling reaction, the first feed pump and the second feed pump are turned on, and at the same time, the second circulation temperature control device and the third circulation temperature control device are activated. The diazo reaction liquid and the dispersant are mixed before entering the first feed pump, and the mixed liquid of the diazo reaction liquid and the dispersant is continuously sprayed out from the first nozzle of the coupling reaction device. The coupling component and the dispersant are mixed before entering the second feed pump, and the mixed liquid of the coupling component and the dispersant is continuously sprayed out from the second nozzle of the coupling reaction device. The first nozzle and the second nozzle spray towards each other, and the second circulation temperature control device and the third circulation temperature control device control the coupling reaction temperature. The second circulation temperature control device mixes the materials in the coupling reaction device with the diazo reaction liquid and the dispersant and sprays them out from the first nozzle. The third circulation temperature control device mixes the materials in the coupling reaction device with the coupling component and the dispersant and sprays them out from the second nozzle. When the potential of the materials in the coupling reaction device reaches a preset value, the coupling discharge valve automatically opens, and the generated liquid dye flows out.

[0030] Compared with the prior art, the present invention has the following advantages:

[0031] 1. The present invention designs an automatic continuous liquid dye production system, realizing the automatic continuous production of azo dyes, especially azo disperse dyes.

[0032] 2. The circulation pipeline of the nitrite feeding device of the present invention is connected to the first circulation temperature control device. Therefore, after the nitrite enters the diazotization reaction device, the third nozzle sprays out the nitrite. After spraying, it enters the diazotization reactor and reacts fully with the diazo component, and the mass transfer effect is very good.

[0033] 3. The present invention designs a potentiometer device for real-time monitoring of the diazotization reaction and the coupling reaction to ensure the full completion of the diazotization reaction and the coupling reaction.

[0034] 4. The present invention controls the temperature through heat exchangers. The heat exchangers are all located outside the diazotization reactor and the coupling reactor, and the heat exchangers and the circulation pipelines are detachably connected. According to different products, the heat release amount of the diazotization reaction is different, and it is very convenient to replace the heat exchanger, thereby adjusting the heat exchange area to ensure that the diazotization reaction is carried out at the optimal temperature.

[0035] 5. Since the coupling reaction is an exothermic reaction, an increase in temperature will cause side reactions to occur. At the same time, the solvent for dissolving the coupling component is usually hydrochloric acid, sulfuric acid or liquid caustic soda. For different properties of coupling components, the amount and concentration of acid or alkali consumed are different. For some coupling components, due to their low solubility, therefore, a higher concentration and a larger amount of acid or alkali are required as solvents, and more water needs to be added for dilution during the dye synthesis process, resulting in a low solid content and a large amount of wastewater. Because of their poor solubility, some even use organic solvents such as glacial acetic acid, methanol, and DMF, which will all bring a large amount of high-COD wastewater and cause great environmental protection pressure.

[0036] Therefore, the first nozzle and the second nozzle are designed. The first feed pump and the second feed pump pump the mixed liquid into the coupling reactor respectively. Since the first nozzle and the second nozzle spray towards each other, intense collision occurs inside the draft tube to cause a reaction. The dispersant is respectively mixed and fed with the diazo reaction liquid and the coupling component in a certain proportion, and the generated dye is immediately dispersed by the dispersant, increasing the stability of the dye. The temperature of the reaction is controlled by the second circulation temperature control device and the third circulation temperature control device to prevent side reactions caused by too high temperature. And the coupling reaction device has 6 outlets, the interval angle of each outlet is 60°, and the two opposite outlets are combined into one stream and flow into the second circulation temperature control device, the third circulation temperature control device and the coupling discharge valve respectively. And the first nozzle and the second nozzle are located inside the draft tube, that is, the distribution design of the draft tube and two circulations and one discharge is designed, so that the concentration gradient in the coupling reactor is as small as possible, facilitating the dissolution of the coupling component, reducing the usage amount of the solvent, and thus reducing the generation of wastewater to ensure the product quality. Brief Description of the Drawings

[0037] Figure 1 is a schematic structural diagram of Embodiment 1 of the present invention;

[0038] Figure 2 is a schematic structural diagram of the diazo reaction device of the present invention;

[0039] Figure 3 is a schematic structural diagram of the coupling reaction device of the present invention;

[0040] Figure 4 is a schematic structural diagram of the outlet of the present invention;

[0041] Figure 5 is a schematic structural diagram of the solid feed device of the present invention;

[0042] Figure 6 is a schematic side structural diagram of the feed runner of the present invention;

[0043] Figure 7 is a schematic structural diagram of Embodiment 2 of the present invention.

[0044] In the figure, 1 is a diazotization reaction device; 2 is a coupling reaction device; 3 is a solid feeding device; 4 is a nitrite feeding device; 5 is a first spray head; 6 is a second spray head; 7 is a dispersant feeding device; 8 is a liquid dye storage device; 9 is a first circulation temperature control device; 10 is a second circulation temperature control device; 11 is a third circulation temperature control device; 12 is a circulation pipeline; 13 is a heat exchanger; 14 is a diazotization reactor; 15 is a third spray head; 16 is a diazotization circulation pump; 17 is a diazo intermediate tank; 18 is a diazo discharge valve; 19 is a coupling discharge valve; 20 is a potentiometer; 21 is a control device; 22 is a coupling reactor; 23 is a draft tube; 24 is an outlet; 25 is a first feed pump; 26 is a second feed pump; 27 is a feed pipeline; 28 is a screw propeller; 29 is a feed runner; 30 is a brushing brush; 31 is a drive motor; 32 is a coupling component feeding device; 33 is a discharge pipeline; 34 is a diazo component elevated tank. Detailed implementation mode

[0045] The following are specific embodiments of the present invention and in combination with the accompanying drawings, the technical solutions of the present invention are further described, but the present invention is not limited to these embodiments.

[0046] Example 1:

[0047] Diazo component: 2,4-dinitro-6-chloroaniline;

[0048] Coupling component: N,N-diethyl-3-acetamidoaniline;

[0049] Product Disperse Violet 93:1 structure:

[0050] Nitrite solution: commercially available nitrosylsulfuric acid solution with a weight percentage of 30%;

[0051] Diazo component: commercially available solid 2,4-dinitro-6-chloroaniline with a content of 98%;

[0052] Coupling component solution: aqueous solution of N,N-diethyl-3-acetamidoaniline with a weight percentage of 10%, adjusted to pH 2-3 with 30% brine.

[0053] Dispersant solution: 30% aqueous solution of commercially available dispersant MF.

[0054] After checking whether the entire continuous production system and the automated control system are normal, 100 kg of 2,4-dinitro-6-chloroaniline is added into the diazotization reactor 14. The diazotization circulation pump 16 is started, and the refrigerant feed of the heat exchanger 13 of the first circulation temperature control device 9 is opened to control the material temperature in the diazotization reactor 14 at 5 - 10°C. 201 kg of nitrosylsulfuric acid is slowly added from the nitrite feed device 4. After the addition of nitrosylsulfuric acid is completed, the diazo component solid feed device is started, and the feed rate of the diazo component 2,4-dinitro-6-chloroaniline is 50 kg / h, and the feed rate of nitrosylsulfuric acid is controlled at 105 kg / h. When the potentiometer 20 on the diazotization reactor 14 shows compliance, the diazo discharge valve 18 is automatically opened, and the finished diazo solution flows into the diazo intermediate tank 17. The first feed pump 25 of the coupling reactor 22 is opened, and the feed rate of the diazo solution is 155 kg / h. The flow rate of the dispersant solution is controlled to be 50% of the feed rate of the diazo solution (i.e., 77.5 kg / h) through the flow rate of the diazo solution feed. At the same time, the refrigerant feeds of the heat exchanger 13 of the second circulation temperature control device 10 and the heat exchanger 13 of the third circulation temperature control device 11 are opened to ensure that the material temperature in the coupling reactor 22 is 5 - 10°C. The feed valve of the coupling component is opened, and the second feed pump 26 is started, and the feed rate of the coupling component is 615 kg / h. The flow rate of the dispersant solution is controlled to be 20% of the feed rate of the coupling component (i.e., 123 kg / h) through the flow rate of the coupling component feed. The progress of the coupling reaction is detected online through the potentiometer 20 on the coupling reactor 22, and the coupling discharge valve 19 is controlled. The finished liquid dye enters the liquid dye storage device 8 to obtain the disperse violet 93:1 liquid dye.

[0055] Example 2:

[0056] Diazo component: 5-amino-6-bromo-2-methylindole-1,3-dione;

[0057] Coupling component: N,N-diethyl-3-acetamidoaniline;

[0058] Product disperse violet 107 structure:

[0059] Nitrite solution: An aqueous solution of sodium nitrite with a weight percentage of 30%;

[0060] Diazo component solution: A 20% hydrochloric acid solution of 5-amino-6-bromo-2-methylindole-1,3-dione by weight (i.e., 50 kg of 5-amino-6-bromo-2-methylindole-1,3-dione is dissolved in 200 kg of 30% hydrochloric acid solution);

[0061] Coupling component solution: An aqueous solution of N,N - diethyl - 3 - acetamidoaniline with a weight percentage of 10%, adjusted to a pH of 2 - 3 with 30% brine;

[0062] Dispersant solution: A 30% aqueous solution of commercially available dispersant MF.

[0063] After checking whether the entire continuous production system and the automated control system are normal, 520 kg of the diazo component solution is added to the diazotization reactor 14. The diazotization circulation pump 16 is started, and the refrigerant feed of the heat exchanger 13 of the first circulation temperature control device 9 is opened. The temperature of the material in the diazotization reactor 14 is controlled at 15 - 20 °C. 120 kg of an aqueous sodium nitrite solution is slowly added from the sodium nitrite feed device 4. After the addition is complete, the feed valve of the diazo component solution is opened, and the feed rate of the diazo component solution is 260 kg / h. The feed valve of the sodium nitrite high - level tank is opened, and the feed rate of the aqueous sodium nitrite solution is 60 kg / h. When the potentiometer 20 on the diazotization reactor 14 shows compliance, the diazo discharge valve 18 is automatically opened, and the finished diazo solution flows into the diazo intermediate tank 17. The first feed pump 25 of the coupling reactor 22 is started, and the feed rate of the diazo solution is 320 kg / h. The dispersant solution is controlled to be 40% of the feed rate of the diazo solution (i.e., 128 kg / h) by the flow rate of the diazo solution feed. At the same time, the refrigerant feeds of the heat exchanger 13 of the second circulation temperature control device 10 and the heat exchanger 13 of the third circulation temperature control device 11 are opened to ensure that the temperature of the material in the coupling reactor 22 is 5 - 10 °C. The feed valve of the coupling component is opened, and the second feed pump 26 is started, and the feed rate of the coupling component is 400 kg / h. The dispersant solution is controlled to be 20% of the feed rate of the coupling component (i.e., 80 kg / h) by the flow rate of the coupling component feed. The progress of the coupling reaction is detected online by the potentiometer 20 on the coupling reactor 22, and the coupling discharge valve 19 is controlled. The finished liquid dye enters the liquid dye storage device 8, and the disperse violet 107 liquid dye is obtained.

[0064] As Figures 1-7 shown, a synthesis system for implementing the above - mentioned production process of an automatic continuous liquid azo dye includes a diazotization reaction device 1 and a coupling reaction device 2. The diazotization reaction device 1 is connected to a diazo component feed device and a sodium nitrite feed device 4. The coupling reaction device 2 includes a first spray head 5 and a second spray head 6. The first spray head 5 and the second spray head 6 are arranged opposite to each other. Both the first spray head 5 and the second spray head 6 are connected to a dispersant feed device 7. The diazotization reaction device 1 is connected to the first spray head 5. The second spray head 6 is also connected to a coupling component feed device 32. The first spray head 5 is used to spray a mixture of a dispersant and a diazotization reaction liquid. The second spray head 6 is used to spray a mixture of a dispersant and a coupling component. The coupling reaction device 2 is connected to a liquid dye storage device 8 for storing the generated dye.

[0065] The diazo component feeding device is used to add the diazo component into the diazo reaction device 1, and the nitrite feeding device 4 is used to add the diazo component into the diazo reaction device 1. The first nozzle 5 and the second nozzle 6 are arranged opposite to each other, that is, the first nozzle 5 and the second nozzle 6 spray against each other. The coupling component and the diazo reaction liquid collide violently to react, and the generated dye is immediately dispersed by the dispersant, increasing the stability of the dye. The produced dye flows into the liquid dye storage device 8 for storage.

[0066] Specifically, the diazo reaction device 1 is provided with a first circulation temperature control device 9, the coupling reaction device 2 is provided with a second circulation temperature control device 10 and a third circulation temperature control device 11. The first circulation temperature control device 9, the second circulation temperature control device 10 and the third circulation temperature control device 11 all include a circulation pipeline 12 and a heat exchanger 13 arranged on the circulation pipeline 12. The second circulation temperature control device 10 is used to circulate the materials in the coupling reaction device 2 from the first nozzle 5 and spray them into the coupling reaction device 2. The third circulation temperature control device 11 is used to circulate the materials in the coupling reaction device 2 from the second nozzle 6 and spray them into the coupling reaction device 2. The second circulation temperature control device 10 and the third circulation temperature control device 11 are both used to control the temperature of the coupling reaction. The first circulation temperature control device 9 is used to circulate the materials in the diazo reaction device 1 and control the temperature of the diazo reaction. One end of the heat exchanger 13 is for the entry of the refrigerant, and the other end of the heat exchanger 13 is for the outflow of the refrigerant. The heat exchanger 13 is used for the heat exchange between the refrigerant and the materials. The heat exchanger 13 and the circulation pipeline 12 are detachably connected.

[0067] The heat exchanger 13 is used for the heat exchange between the refrigerant and the materials. Since both the diazo reaction and the coupling reaction are exothermic reactions, the heat exchanger 13 can be used to control the reaction temperature. The heat exchangers 13 are all located outside the diazotization reactor 14 and the coupling reactor 22, and the heat exchanger 13 and the circulation pipeline 12 are detachably connected. According to different products, the heat release of the diazotization reaction is different, and the heat exchanger 13 can be very conveniently replaced, so as to adjust the heat exchange area and ensure that the diazotization reaction is carried out at the optimal temperature.

[0068] Specifically, the diazo reaction device 1 includes a diazotization reactor 14. A third nozzle 15 is arranged at the top of the diazotization reactor 14. One end of the circulation pipeline 12 of the first circulation temperature control device 9 is connected to the bottom of the diazotization reactor 14, and the other end of the circulation pipeline 12 of the first circulation temperature control device 9 is immersed in the materials inside the diazotization reactor 14 from the top of the diazotization reactor 14. The third nozzle 15 is located in the circulation pipeline 12 of the first circulation temperature control device 9. A diazotization circulation pump 16 is arranged on the circulation pipeline 12 of the first circulation temperature control device 9. The nitrite feeding device 4 is connected to the circulation pipeline 12 of the first circulation temperature control device 9.

[0069] After the nitrite enters the diazotization reaction device 1, the third nozzle 15 sprays out the nitrite. After spraying, it enters the diazotization reactor 14 and reacts fully with the diazo component, and the mass transfer effect is very good.

[0070] To elaborate further, a diazo intermediate tank 17 is provided between the diazotization reaction device 1 and the coupling reaction device 2. A diazo discharge valve 18 is provided between the diazo intermediate tank 17 and the diazotization reaction device 1. The liquid dye storage device 8 and the coupling reaction device 2 are connected through a discharge pipeline 33. A coupling discharge valve 19 is provided on the discharge pipeline 33. The diazotization reactor 14 and the coupling reactor 22 are both provided with a potentiometer 20 for detecting the potential. The potentiometer 20 is communicatively connected to a control device 21. The potentiometer 20 is used to transmit the detected potential information to the control device 21. The control device 21 controls the opening or closing of the diazo discharge valve 18 and the coupling discharge valve 19 according to the potential information, and controls the opening size of the diazo discharge valve 18 and the coupling discharge valve 19.

[0071] The potentiometer 20 that monitors the potential of the diazotization reaction and the coupling reaction in real time ensures the full completion of the diazotization reaction and the coupling reaction.

[0072] In order to generate different dyes, different coupling components and diazo components are selected. The preset value of the potentiometer 20 can be set as needed. When the potential of the material in the diazotization reactor reaches the preset value, the potentiometer 20 transmits the detected potential information to the control device 21. The control device 21 controls the opening or closing of the diazo discharge valve 18 and the coupling discharge valve 19 according to the potential information. The control device 21 can also control the opening size of the diazo discharge valve 18 and the coupling discharge valve 19 according to the potential information, so as to control the flow rate flowing out of the diazo discharge valve 18 and the coupling discharge valve 19. The control device 21 is existing. The potentiometer 20, the diazo discharge valve 18 and the coupling discharge valve 19 can be purchased on the market.

[0073] To elaborate further, the coupling reaction device 2 includes a tubular coupling reactor 22 and a draft tube 23 provided inside the coupling reactor 22. The first nozzle 5 and the second nozzle 6 are located at both ends of the draft tube 23. Six outlets 24 are evenly distributed in the middle of the coupling reactor 22. The interval angle of each outlet 24 is 60°. The two pairwise opposite outlets 24 are respectively communicated with the second circulation temperature control device 10, the third circulation temperature control device 11 and the discharge pipeline 33 through pipelines.

[0074] That is, a draft tube 23 and a distribution design of two circulations and one discharge are designed to minimize the concentration gradient in the coupling reactor 22, facilitate the dissolution of the coupling components, reduce the amount of solvent used, and thus reduce the generation of wastewater to ensure product quality.

[0075] Specifically, the first spray head 5 is connected to a first feed pump 25, and the second spray head 6 is connected to a second feed pump 26. The first feed pump 25 is used to pump the mixture of the materials, diazo reaction liquid and dispersant in the coupling reaction device 2 into the first spray head 5, and the second feed pump 26 is used to pump the mixture of the materials, coupling components and dispersant in the coupling reaction device 2 into the second spray head 6.

[0076] The diazo reaction liquid and the dispersant are mixed before entering the first feed pump 25, and the coupling components and the dispersant are mixed before entering the second feed pump 26. Then they are sprayed out through the first spray head 5 and the second spray head 6, and react by colliding inside the draft tube 23. Once the dye product is formed, it is dispersed by the dispersant to avoid dye aggregation. And a part of the materials in the coupling reaction device 2 circulate, are mixed with the diazo reaction liquid and the dispersant, and are sprayed out from the first spray head 5. Another part is mixed with the diazo components and the dispersant and is sprayed out from the second spray head 6 to further strengthen the collision between the materials and improve the reaction yield.

[0077] The first spray head 5, the second spray head 6, and the third spray head 15 are Venturi jet reactors, which are beneficial to heat transfer and mass transfer.

[0078] The diazo component feeding device can be the solid feeding device 3 or the diazo component elevated tank 34. The solid feeding device 3 and the diazo component elevated tank 34 are respectively selected according to whether the diazo component is solid or liquid in the production process of different products.

[0079] The solid feeding device includes a feeding pipeline 27, a screw propeller 28, a feeding runner 29, and a brushing brush 30 which are sequentially arranged in the feeding pipeline 27 from top to bottom. The screw propeller 28, the feeding runner 29, and the brushing brush 30 are all provided with driving motors 31. The screw propeller 28 is used to push the solid materials to move in the feeding pipeline 27, the feeding runner 29 is used to control the feeding amount, and the brushing brush 30 is used to brush the materials adhered to the feeding runner 29 into the diazotization reactor. A good linear relationship can be formed between the rotation speeds of the feeding screw, the feeding runner 29, and the brushing brush 30 and the feeding amount of the solid materials to achieve the purpose of accurate and continuous feeding of the solid materials.

[0080] Feed valves for controlling the flow rate are provided between the diazo component feeding device, the nitrite feeding device 4 and the diazo reaction device 1, and between the dispersant feeding device 7, the diazo intermediate tank 17, the coupling component feeding device 32 and the coupling reaction device 2.

[0081] The refrigerant can be cooling water.

[0082] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Those skilled in the art to which the present invention pertains can make various modifications or supplements to the described specific embodiments or use similar ways to replace them, but will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0083] Although terms such as diazo reaction device 1, coupling reaction device 2, solid feeding device 3, nitrite feeding device 4, first spray head 5, second spray head 6, dispersant feeding device 7, liquid dye storage device 8, first circulation temperature control device 9, second circulation temperature control device 10, third circulation temperature control device 11, circulation pipeline 12, heat exchanger 13, diazotization reactor 14, third spray head 15, diazotization circulation pump 16, diazo intermediate tank 17, diazo discharge valve 18, coupling discharge valve 19, potentiometer 20, control device 21, coupling reactor 22, draft tube 23, outlet 24, first feed pump 25, second feed pump 26, feed pipeline 27, screw propeller 28, feed runner 29, brushing brush 30, drive motor 31, coupling component feeding device 32, discharge pipeline 33, diazo component elevated tank 34 are used more frequently herein, the possibility of using other terms is not excluded. Using these terms is only for more conveniently describing and explaining the essence of the present invention; interpreting them as any additional limitation is contrary to the spirit of the present invention.

Claims

1. A production process for automatic continuous liquid azo dyes, characterized in that, a synthesis system adopting the production process for automatic continuous liquid azo dyes comprises a diazotization reaction device (1) and a coupling reaction device (2). The diazotization reaction device (1) is connected with a diazo component feeding device and a nitrite feeding device (4). The coupling reaction device (2) comprises a first spray head (5) and a second spray head (6). The first spray head (5) and the second spray head (6) are arranged oppositely. Both the first spray head (5) and the second spray head (6) are connected with a dispersant feeding device (7). The diazotization reaction device (1) is connected with the first spray head (5). The second spray head (6) is further connected with a coupling component feeding device (32). The first spray head (5) is used for spraying a mixture of a dispersant and a diazotization reaction liquid. The second spray head (6) is used for spraying a mixture of a dispersant and a coupling component. The coupling reaction device (2) is connected with a liquid dye storage device (8) for storing the generated dyes; the diazotization reaction device (1) is provided with a first circulation temperature control device (9). The coupling reaction device (2) is provided with a second circulation temperature control device (10) and a third circulation temperature control device (11). The first circulation temperature control device (9), the second circulation temperature control device (10) and the third circulation temperature control device (11) all comprise a circulation pipeline (12) and a heat exchanger (13) arranged on the circulation pipeline (12). The second circulation temperature control device (10) is used for circulating the materials in the coupling reaction device (2) from the first spray head (5) into the coupling reaction device (2). The third circulation temperature control device (11) is used for circulating the materials in the coupling reaction device (2) from the second spray head (6) into the coupling reaction device (2). Both the second circulation temperature control device (10) and the third circulation temperature control device (11) are used for controlling the temperature of the coupling reaction. The first circulation temperature control device (9) is used for circulating the materials in the diazotization reaction device (1) and controlling the temperature of the diazotization reaction. One end of the heat exchanger (13) is for the entry of a refrigerant, and the other end of the heat exchanger (13) is for the outflow of the refrigerant. The heat exchanger (13) is used for heat exchange between the refrigerant and the materials. The heat exchanger (13) and the circulation pipeline (12) are detachably connected; the coupling reaction device (2) comprises a tubular coupling reactor (22) and a draft tube (23) arranged inside the coupling reactor (22). The first spray head (5) and the second spray head (6) are located at both ends of the draft tube (23). Six outlets (24) are evenly distributed in the middle of the coupling reactor (22). The interval angle of each outlet (24) is 60°. The two outlets (24) facing each other are respectively communicated with the second circulation temperature control device (10), the third circulation temperature control device (11) and a discharge pipeline (33) through pipelines; The described first nozzle (5) is connected to a first feed pump (25), and the second nozzle (6) is connected to a second feed pump (26). The first feed pump (25) is used to pump the mixed liquid of the materials, diazo reaction liquid, and dispersant in the coupling reaction device (2) into the first nozzle (5), and the second feed pump (26) is used to pump the mixed liquid of the materials, coupling component, and dispersant in the coupling reaction device (2) into the second nozzle (6); A diazo intermediate tank (17) is arranged between the diazo reaction device (1) and the coupling reaction device (2). A diazo discharge valve (18) is arranged between the diazo intermediate tank (17) and the diazo reaction device (1). The liquid dye storage device (8) and the coupling reaction device (2) are connected through a discharge pipeline (33). A coupling discharge valve (19) is arranged on the discharge pipeline (33). A potentiometer (20) for detecting the potential is arranged on both the coupling reactor (22) and the diazotization reactor (14). The potentiometer (20) is communicatively connected to a control device (21). The potentiometer (20) is used to transmit the detected potential information to the control device (21). The control device (21) controls the opening or closing of the diazo discharge valve (18) and the coupling discharge valve (19), and controls the opening size of the diazo discharge valve (18) and the coupling discharge valve (19) according to the potential information; The coupling reaction device (2) has 6 outlets (24), and the angular interval of each outlet (24) is 60°. The two pairwise opposite outlets (24) are combined into one stream and flow into the second circulation temperature control device (10), the third circulation temperature control device (11), and the coupling discharge valve (19) respectively; This process includes the following steps: S01: Add diazo components to the diazo reaction device (1), turn on the first circulation temperature control device (9), and then add nitrite to the diazo reaction device (1). The first circulation temperature control device (9) circulates the materials in the diazo reaction device (1) and controls the diazo reaction temperature; S02: Continuously add diazo components and nitrite to the diazo reaction device (1); open the diazo discharge valve (18), and the diazo reaction liquid flows out; S03: Turn on the first feed pump (25) and the second feed pump (26), and at the same time turn on the second circulation temperature control device (10) and the third circulation temperature control device (11). The diazo reaction liquid and the dispersant are mixed before entering the first feed pump (25), and the coupling component and the dispersant are mixed before entering the second feed pump (26); The mixed liquid of the diazo reaction liquid and the dispersant continuously sprays out from the first nozzle (5) of the coupling reaction device (2). At the same time, the mixed liquid of the coupling component and the dispersant continuously sprays out from the second nozzle (6) of the coupling reaction device (2). The first nozzle (5) and the second nozzle (6) spray against each other; both the second circulation temperature control device (10) and the third circulation temperature control device (11) are used to circulate the materials in the coupling reaction device (2) and control the coupling reaction temperature; S04: Open the coupling discharge valve (19) to obtain liquid dye.

2. The production process of an automatic continuous liquid azo dye according to claim 1, characterized in that, in step S03, the second circulation temperature control device (10) mixes the materials in the coupling reaction device (2) with the diazo reaction liquid and the dispersant, and sprays them out from the first nozzle (5), and the third circulation temperature control device (11) mixes the materials in the coupling reaction device (2) with the coupling component and the dispersant, and sprays them out from the second nozzle (6).

3. The production process of an automatic continuous liquid azo dye according to claim 1, characterized in that, in step S02, when the potential of the materials in the diazo reaction device (1) reaches a preset value, the diazo discharge valve (18) automatically opens; in step S04, when the potential of the materials in the coupling reaction device (2) reaches a preset value, the coupling discharge valve (19) automatically opens.

4. The production process of an automatic continuous liquid azo dye according to claim 1, characterized in that, in step S03, the diazo reaction liquid and the dispersant are mixed, and the amount of the dispersant is 40-50% of the feeding amount of the diazo reaction liquid; the coupling combination and the dispersant are mixed, and the amount of the dispersant is 20% of the feeding amount of the coupling component.

5. The production process of an automatic continuous liquid azo dye according to claim 1, characterized in that, the diazo reaction device (1) includes a diazotization reactor (14), a third nozzle (15) is arranged at the top of the diazotization reactor (14), one end of the circulation pipeline (12) of the first circulation temperature control device (9) is connected to the bottom of the diazotization reactor (14), the other end of the circulation pipeline (12) of the first circulation temperature control device (9) is immersed in the materials inside the diazotization reactor (14) from the top of the diazotization reactor (14), the third nozzle (15) is located in the circulation pipeline (12) of the first circulation temperature control device (9), a diazotization circulation pump (16) is arranged on the circulation pipeline (12) of the first circulation temperature control device (9), and the nitrite feeding device (4) is connected to the circulation pipeline (12) of the first circulation temperature control device (9).

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