A method for preparing 1-nitroanthraquinone using a dynamic tubular reactor

Abstract

The application discloses a dynamic tubular reactor and a method for preparing 1-nitroanthraquinone by using the dynamic tubular reactor, which comprises a reactor body; the inside of the reactor body comprises a mixing area, a mass transfer area and a time-delay reaction area; a heat exchange unit is arranged on the reactor body; a first material inlet and a second material inlet are arranged on the top of the reactor body; a mixing area is arranged above the inside of the reactor body; a mixing baffle is arranged at the bottom of the mixing area; a first discharging channel is arranged in the center of the mixing baffle; the dynamic tubular reactor can make the material uniformly heated and mixed during the reaction process, avoids caking and blockage, and improves the reaction efficiency.

Description

Technical Field

[0001] This invention relates to the field of chemical engineering, and specifically to a method for preparing 1-nitroanthraquinone using a dynamic tubular reactor. Background Technology

[0002] 1-Nitroanthraquinone is one of the most important anthraquinone derivatives and is widely used in drug synthesis, dyes and other fine chemicals. 1-Aminoanthraquinone is an intermediate in the synthesis of various anthraquinone dyes and is mainly used in the production of anthraquinone dyes. It is also used in inks, coatings, pigments, liquid crystal dyes, photosensitizers, and catalysts for the catalytic reduction of H2O2, etc., with a wide range of applications.

[0003] Traditional methods for synthesizing 1-nitroanthraquinone include pure nitric acid nitration, mixed acid (HNO3 + H2SO4) nitration, and solvent nitration. Pure nitric acid nitration is difficult to digest, requires a large amount of nitric acid (anthraquinone:nitric acid = 20), produces many byproducts, is difficult to process, and has a low yield of around 70%. Furthermore, the water generated during the reaction dilutes the nitric acid concentration, increasing oxidation. Mixed acid nitration exhibits strong nitration activity and a yield approximately 75% higher than pure nitric acid nitration, but requires a large amount of mixed acid to increase the fluidity of the reaction system; otherwise, the raw materials will have poor flowability and mixing. Solvent nitration involves adding an inert organic solvent to the mixed acid to increase the fluidity of the raw materials and reduce the amount of mixed acid used. Solvent nitration is currently the most commonly used method for preparing 1-nitroanthraquinone. Traditional 1-nitroanthraquinone production processes are carried out in reaction kettles, which present problems such as flammability and explosiveness, low product conversion and purity, large amounts of waste acid generation, and long reaction cycles. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing 1-nitroanthraquinone using a dynamic tubular reactor, so as to reduce the amount of mixed acid used and improve the product yield.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A method for preparing 1-nitroanthraquinone using a dynamic tubular reactor includes the following steps:

[0007] S1. Preparation of the mixture: Mix anthraquinone, dichloroethane and nitric acid. Adjust the content of dichloroethane according to experimental requirements to ensure that the mixture can enter the dynamic tubular reactor for reaction.

[0008] S2. Feeding: The mixture of anthraquinone, dichloroethane, and nitric acid is one phase. The mixture is a pale yellow crystalline slurry with a solid content of about 30%. It is fed into the reactor at room temperature via a peristaltic pump. Sulfuric acid is the other phase material and is transported into the reactor at room temperature via a horizontal flow pump. The ratio of the two phase materials is adjusted.

[0009] S3. Heat exchange: heat exchange unit is used to control temperature during reaction, so that the reaction temperature is maintained at 30-60℃;

[0010] S4. Residence: the residence time of the reaction after mixing of the two-phase materials is 60-360s, the reaction is carried out under normal pressure, the mixing liquid feed flow is 50-100 mL / min, and the sulfuric acid feed flow is 5-40 mL / min;

[0011] S5. Discharge: after the reaction is stopped for a certain time, the material is discharged from the dynamic tubular reactor.

[0012] Further, the material ratio is mass ratio anthraquinone: dichloroethane: nitric acid = 1:1-4:0.4; anthraquinone: sulfuric acid = 1:0.6-0.9.

[0013] A dynamic tubular reactor comprises a reactor body 1; the inside of the reactor body 1 comprises a mixing zone 2, a mass transfer zone 3, and a delay reaction zone 4; a heat exchange unit 5 is connected and arranged on the reactor body 1;

[0014] The top of the reactor body 1 is provided with a first material inlet 6 and a second material inlet 7; the inside of the reactor body 1 is provided with the mixing zone 2 at the top; the bottom of the mixing zone 2 is provided with a mixing baffle 8; the central part of the mixing baffle 8 is provided with a first discharging channel 9;

[0015] The delay reaction zone 4 is arranged below the mixing zone 2;

[0016] The mass transfer zone 3 comprises a first mass transfer zone 3.1 and a second mass transfer zone 3.2; the first mass transfer zone 3.1 is arranged around the outer wall of the delay reaction zone 4; the second mass transfer zone 3.2 is arranged in the center of the delay reaction zone 4; the first mass transfer zone 3.1 is provided with an outer heat transfer medium inlet 10 and an outer heat transfer medium outlet 11; the second mass transfer zone 3.2 is provided with an inner heat transfer medium inlet 12 and an inner heat transfer medium outlet 13; the outer heat transfer medium inlet 10 and the inner heat transfer medium inlet 12 are respectively connected with the liquid outlet of the heat exchange unit 5; the outer heat transfer medium outlet 11 and the inner heat transfer medium outlet 13 are respectively connected with the liquid inlet of the heat exchange unit 5;

[0017] The sidewall of the reactor body 1 is provided with a product outlet 14; the product outlet 14 is provided with a product discharging channel 15.

[0018] Further, the second mass transfer zone 3.2 is arranged as a cylindrical structure; a rotating shaft 16 is arranged in the center of the second mass transfer zone 3.2; a rotating motor 17 is connected to the bottom of the rotating shaft 16; the rotating motor 17 drives the overall rotating movement of the second mass transfer zone 3.2; the inner surface of the reactor body 1 is arranged as a cylindrical structure; the rotating shaft 16 is arranged on the straight line of the central axis of the reactor body; a liquid reaction gap 18 is arranged between the outer surface of the second mass transfer zone 3.2 and the inner surface of the reactor body 1.

[0019] Further, a PLC controller 20 and a temperature sensor are further included; the temperature sensor is arranged inside the reactor body 1; the PLC controller 20 is arranged outside the reactor body 1; the temperature sensor is in control connection with the PLC controller 20.

[0020] Further, a viscosity sensor is further included; the viscosity sensor is in control connection with the PLC controller 20.

[0021] Further, flow valves are arranged on the first material inlet 6, the second material inlet 7, the outer heat transfer medium inlet 10, the inner heat transfer medium inlet 12, the outer heat transfer medium outlet 11, the inner heat transfer medium outlet 13 and the product outlet 14; the flow valves are in control connection with the PLC controller 20; the rotating motor 17 is connected with the PLC controller 20.

[0022] Further, the width of the liquid reaction gap 18 is arranged as 1mm-5mm.

[0023] Further, the heat exchange unit 5 is arranged as a cold and hot integrated machine.

[0024] Compared with the prior art, the present application has at least one of the following beneficial effects:

[0025] The preparation method of the present application can effectively solve the problems of high by-product content, low raw material conversion rate, large amount of waste acid, safety risk and the like in the traditional process; in the prior art, a continuous flow plate reactor is generally used for the preparation of 1-nitroanthraquinone, but since the plate reactor cannot have solid, a large amount of sulfuric acid and dichloroethane are needed to dissolve the raw material to form a saturated solution. The reactor of the present application can have about 30% solid slurry, and does not need to use a large amount of sulfuric acid and dichloroethane to dissolve the raw material anthraquinone.

[0026] The method for using the dynamic tubular reactor described in the application is as follows: first, two materials are introduced into the mixing area 2 in the reactor body 1 through the first material inlet 6 and the second material inlet 7 in proportion, and under the action of the mixing baffle 8, the two materials are initially mixed, and the initially mixed materials enter the reactor body 1 and enter the liquid reaction gap 18 from top to bottom under high-speed rotation to generate shear force, so that the materials form a liquid film in the gap and are mixed in this form to enhance the heat and mass transfer effect.

[0027] In summary, the use of the dynamic tubular reactor described in the application can make the materials uniformly heated and mixed during the reaction, avoid caking and blockage, and improve the reaction efficiency. The heat exchange unit adopts a cold and hot all-in-one machine for precise temperature control, appropriately increases the reaction temperature, and the reaction rate is increased accordingly. The reactor equipment of the application has a small floor area, saves land, and has a PLC control system, which is easy to operate, has a high degree of automation, and saves manpower. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The figure is a structural schematic diagram of the application;

[0029] In the figure: reactor body 1; mixing area 2; mass transfer area 3; delay reaction area 4; heat exchange unit 5; first material inlet 6; second material inlet 7; mixing baffle 8; first discharge channel 9; outer heat transfer medium inlet 10; outer heat transfer medium outlet 11; inner heat transfer medium inlet 12; inner heat transfer medium outlet 13; product outlet 14; product discharge channel 15; rotating shaft 16; rotating motor 17; liquid reaction gap 18; PLC controller 20; mechanical seal 22. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the application clearer and more apparent, the application will be further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the application and do not limit the application.

[0031] As shown in the figure:

[0032] Example 1: A method for preparing 1-nitroanthraquinone by using a dynamic tubular reactor, comprising the following steps:

[0033] S1. Configuration of the mixed liquid: mixing anthraquinone, dichloroethane and nitric acid, adjusting the content of dichloroethane according to experimental requirements, and ensuring that the mixed liquid can enter the dynamic tubular reactor for reaction;

[0034] S2. Feeding: the mixture of anthraquinone, dichloroethane and nitric acid is a phase, the mixture is light yellow crystal, the slurry with solid content of about 30%, and the slurry is fed into the reactor at room temperature by a peristaltic pump, and sulfuric acid is fed into the reactor at room temperature by a horizontal flow pump; the ratio of the two phases of raw materials is adjusted;

[0035] S3. Heat exchange: the reaction temperature is controlled to be maintained at 30-60°C by using a heat exchange unit during the reaction;

[0036] S4. Residence: the residence time of the reaction is 60-360s after the two-phase materials are mixed, the reaction is carried out at normal pressure, the feeding flow of the mixture is 50-100mL / min, and the feeding flow of sulfuric acid is 5-40mL / min;

[0037] S5. Discharge: after the reaction is stopped for a certain time, the materials are discharged from the dynamic tubular reactor.

[0038] Example 2:

[0039] Based on example 1:

[0040] The material ratio is mass ratio anthraquinone:dichloroethane:nitric acid = 1:1-4:0.4; anthraquinone:sulfuric acid = 1:0.6-0.9.

[0041] Example 3:

[0042] Based on examples 1-2:

[0043] A dynamic tubular reactor comprises a reactor body 1; the inside of the reactor body 1 comprises a mixing zone 2, a mass transfer zone 3 and a delay reaction zone 4; a heat exchange unit 5 is connected and arranged on the reactor body 1;

[0044] The top of the reactor body 1 is provided with a first material inlet 6 and a second material inlet 7; the inside of the reactor body 1 is provided with the mixing zone 2 at the top; the bottom of the mixing zone 2 is provided with a mixing baffle 8; the central part of the mixing baffle 8 is provided with a first discharging channel 9;

[0045] The delay reaction zone 4 is arranged below the mixing zone 2;

[0046] The mass transfer zone 3 comprises a first mass transfer zone 3.1 and a second mass transfer zone 3.2; the first mass transfer zone 3.1 is arranged around the outer wall of the delay reaction zone 4; the second mass transfer zone 3.2 is arranged in the center of the delay reaction zone 4; the first mass transfer zone 3.1 is provided with an outer heat transfer medium inlet 10 and an outer heat transfer medium outlet 11; the second mass transfer zone 3.2 is provided with an inner heat transfer medium inlet 12 and an inner heat transfer medium outlet 13; the outer heat transfer medium inlet 10 and the inner heat transfer medium inlet 12 are respectively connected with the liquid outlet of the heat exchange unit 5; the outer heat transfer medium outlet 11 and the inner heat transfer medium outlet 13 are respectively connected with the liquid inlet of the heat exchange unit 5;

[0047] The side wall of the reactor body 1 is provided with a product outlet 14; the product outlet 14 is provided with a product discharge channel 15. The present application makes the heating of the reactant more complete and uniform by arranging the inner and outer mass transfer zones.

[0048] Example 4:

[0049] Based on examples 1-3:

[0050] The second mass transfer zone 3.2 is arranged in a cylindrical structure; the central part of the second mass transfer zone 3.2 is provided with a rotating shaft 16; the bottom of the rotating shaft 16 is connected with a rotating motor 17; the rotating motor 17 drives the overall rotating movement of the second mass transfer zone 3.2; the inner surface of the reactor body 1 is arranged in a cylindrical structure; the rotating shaft 16 is arranged on the straight line of the central axis of the reactor body; the liquid reaction gap 18 is arranged between the outer surface of the second mass transfer zone 3.2 and the inner surface of the reactor body 1.

[0051] In this embodiment, the second mass transfer zone 3.2 is arranged in a cylindrical structure, and the rotating shaft 16 is arranged inside; the rotating shaft 16 drives the overall movement of the second mass transfer zone 3.2 under the action of the rotating motor 17; the rotating shaft 16 and the reactor body 1 are provided with a mechanical seal 22; the rotating shaft 16 is hollow and communicates with the cylindrical structure area of the second mass transfer zone 3.2; the inner heat transfer medium inlet communicates with the cylindrical structure area of the second mass transfer zone 3.2 to inject liquid; the inner heat transfer medium outlet communicates with the rotating shaft 16 to flow out the liquid, realizes the mass transfer process, and the sealing structure at each joint position is arranged according to the requirement.

[0052] Example 5:

[0053] Based on examples 1-4:

[0054] It also comprises a PLC controller 20 and a temperature sensor; the temperature sensor is arranged inside the reactor body 1; the PLC controller 20 is arranged outside the reactor body 1; the temperature sensor is connected with the PLC controller 20.

[0055] Example 6:

[0056] Based on the embodiments 1-5:

[0057] Further comprising a viscosity sensor; the viscosity sensor is in control connection with the PLC controller 20.

[0058] Embodiment 7:

[0059] Based on the embodiments 1-6: flow valves are arranged on the first material inlet 6, the second material inlet 7, the outer heat transfer medium inlet 10, the inner heat transfer medium inlet 12, the outer heat transfer medium outlet 11, the inner heat transfer medium outlet 13 and the product outlet 14; the flow valves are in control connection with the PLC controller 20; the rotating motor 17 is connected with the PLC controller 20.

[0060] Embodiment 8:

[0061] Based on the embodiments 1-7: the width of the liquid reaction gap 18 is set to 1mm-5mm.

[0062] Embodiment 9:

[0063] Based on the embodiments 1-8: the heat exchange unit 5 is set to a cold and hot all-in-one machine.

[0064] The method for using the dynamic tubular reactor described in the application is as follows: first, two materials are proportionally introduced into the mixing area 2 in the reactor body 1 through the first material inlet 6 and the second material inlet 7, and under the action of the mixing baffle 8, the two materials are initially mixed, and the initially mixed materials enter the liquid reaction gap 18 in the reactor body 1 from top to bottom, and under high-speed rotation, shear force is generated, so that the materials form a layer of liquid film in the gap, and the materials are mixed in this form for a local microcirculation, thereby enhancing the heat and mass transfer effect.

[0065] In summary, by using the dynamic tubular reactor described in the application, the materials can be uniformly heated and mixed during the reaction, and caking and blockage can be avoided, thereby improving the reaction efficiency. The heat exchange unit adopts a cold and hot all-in-one machine for precise temperature control, the reaction temperature is appropriately increased, and the reaction rate is increased accordingly; the reactor equipment of the application has a small land occupation, saves land, and at the same time, the PLC control system is easy to operate, has a high degree of automation, and saves manpower.

[0066] Embodiment 10:

[0067] Effect of the addition amount of dichloroethane on the reaction:

[0068] A method for preparing 1-nitroanthraquinone by using a dynamic tubular reactor, comprising the following steps:

[0069] 1. Preparation of mixed solution: anthraquinone, dichloroethane and nitric acid are mixed in a mass ratio of 1:2-1-4:0.4 for standby.

[0070] 2. Feeding: The mixture of anthraquinone, dichloroethane and nitric acid is fed into the reactor by a peristaltic pump at room temperature as a single phase, and sulfuric acid is fed into the reactor by a peristaltic pump at room temperature as another phase; the ratio of the two phases is adjusted.

[0071] 3. Adjusting the frequency of the rotating motor to 30 Hz.

[0072] 4. Heat exchange system: The temperature is controlled by using a cold and hot all-in-one machine during the reaction, so that the reaction temperature is maintained at 40°C.

[0073] 5. Material ratio: anthraquinone:dichloroethane:nitric acid = 1:1-4:0.4 (mass ratio), anthraquinone:sulfuric acid = 1:0.6 (mass ratio).

[0074] 6. Residence time: when step 2 is carried out, the two-phase material is mixed, the mixture is fed into the reactor at a flow rate of 85.4 g / min as a single phase, and sulfuric acid is fed into the reactor at a flow rate of 15 g / min as another phase; the residence time of the two-phase material in the reactor is calculated to be 300 s, the reactor cavity holds 500 mL of liquid, and the reaction is carried out at normal pressure.

[0075] Take 1700g of anthraquinone, then add 1700g, 3400g, 5100g, 6800g of dichloroethane respectively in four experiments, add 680g of nitric acid, store the prepared mixture, then take out the prepared sulfuric acid solution, and find that the change of the content of dichloroethane in this interval has little effect on the conversion rate of the reaction, in order to ensure that the mixture with high solid content can smoothly enter the reactor, the minimum amount of dichloroethane added is 3400g, the reaction temperature is controlled at 40°C under the experimental conditions, the reaction time is 240s, the frequency of the motor is 30Hz, and finally the conversion rate of the raw material is detected by liquid chromatography to be 89%, and the product accounts for 74%.

[0076] Example 11:

[0077] Effect of stirring intensity on the reaction:

[0078] A method for preparing 1-nitroanthraquinone by using a dynamic tubular reactor, comprising the following steps:

[0079] 1. Preparation of the mixture: mix anthraquinone, dichloroethane and nitric acid in a ratio of 1:2:0.4 by mass for standby use.

[0080] 2. Feeding: the mixture of anthraquinone, dichloroethane and nitric acid is fed into the reactor by a peristaltic pump at room temperature as a single phase, and sulfuric acid is fed into the reactor by a peristaltic pump at room temperature as another phase; the ratio of the two phases is adjusted.

[0081] 3. Change the frequency of the rotating motor to 4-40 Hz.

[0082] 4. Heat exchange system: The temperature is controlled by using the cold and hot integrated machine during the reaction, so that the reaction temperature is maintained at 40°C.

[0083] 5. Material ratio: Anthraquinone: dichloroethane: nitric acid = 1:2:0.4 mass ratio, anthraquinone: sulfuric acid = 1:0.6 mass ratio.

[0084] 6. Residence time: When carrying out step 2 reaction, the two-phase material is mixed, the mixed solution is one phase with a flow rate of 85.4 g / min, and sulfuric acid is another phase material with a flow rate of 15 g / min into the reactor. It is calculated that the residence time of the two-phase material in the reactor is 300 s.

[0085] Take 1700g anthraquinone, then add 3400g dichloroethane, 680g nitric acid, and store the prepared mixed solution for standby, then take out the prepared concentrated sulfuric acid, then the two-phase material is transported into the reactor through the corresponding metering tool, the mixed solution and the sulfuric acid solution are respectively fed into the reactor at a flow rate of 85.4 g / min and 10.5 g / min, and the reaction temperature is controlled at 40°C for 300s to obtain the final product. It is found by HPLC detection that when the motor frequency is 30Hz, the raw material conversion rate is as high as 90%, and the product accounts for 81%, and the raw material conversion rate basically does not change as the motor frequency increases

[0086] Example 12:

[0087] Effect of temperature on reaction:

[0088] A method for preparing 1-nitroanthraquinone by using a dynamic tubular reactor, comprising the following steps:

[0089] 1. Preparation of mixed solution: Mix anthraquinone, dichloroethane and nitric acid in a ratio of 1:2:0.4 by mass for standby.

[0090] 2. Feeding: The mixed solution of anthraquinone, dichloroethane and nitric acid is fed into the reactor by peristaltic pump at room temperature as one phase, and sulfuric acid is fed into the reactor by a horizontal flow pump at room temperature as another phase; adjust the ratio of the two-phase raw materials.

[0091] 3. Heat exchange system: The temperature is controlled by using the cold and hot integrated machine during the reaction, so that the reaction temperature is maintained at 30°C-60°C.

[0092] 4. Material ratio: Anthraquinone: dichloroethane: nitric acid = 1:2:0.4 mass ratio, anthraquinone: sulfuric acid = 1:0.6 mass ratio.

[0093] 5. Residence time: when performing step 2, the two-phase material is mixed, the mixed liquid is one phase, and the sulfuric acid is another phase material which enters the reactor at a flow rate of 15 g / min, and the residence time of the two-phase material in the reactor is calculated to be 300 s.

[0094] Take 1700 g of anthraquinone, then add 3400 g of dichloroethane, 680 g of nitric acid, and store the prepared mixture for later use. Then take the prepared nitric acid mixture, and then send the two-phase material into the reactor through the corresponding metering tools. Control the reaction temperature to be between 30-60°C with a temperature gradient, and the reaction time is 300 s, and the motor frequency is 30 Hz to obtain the final product. The product is detected by HPLC, and it is found that when the reaction temperature is 55°C, the conversion rate of the raw material is as high as 92%, and the product accounts for 84%.

[0095] Example 13:

[0096] Effect of material ratio of anthraquinone and sulfuric acid on the reaction:

[0097] A method for preparing 1-nitroanthraquinone using a dynamic tubular reactor, comprising the following steps:

[0098] 1. Preparation of mixed solution: mix anthraquinone, dichloroethane and nitric acid in a mass ratio of 1:2:0.4 for later use.

[0099] 2. Feeding: the mixed solution of anthraquinone, dichloroethane and nitric acid is fed into the reactor by a peristaltic pump at room temperature, and the sulfuric acid is fed into the reactor by a horizontal flow pump at room temperature; adjust the ratio of the two-phase raw materials.

[0100] 3. Heat exchange system: use a cold and hot all-in-one machine to control the temperature during the reaction, so that the reaction temperature is maintained at 55°C.

[0101] 4. Material ratio: anthraquinone:dichloroethane:nitric acid=1:2:0.4 by mass, anthraquinone:sulfuric acid=1:0.6-0.9 by mass.

[0102] 5. Residence time: when performing step 2, the two-phase material is mixed, the mixed liquid is one phase, and the sulfuric acid is another phase material which enters the reactor at a flow rate of 15 g / min, and the residence time of the two-phase material in the reactor is calculated to be 300 s.

[0103] Take 1700g anthraquinone, then add 3400g dichloroethane, nitric acid 680g, the prepared mixture is stored for standby, then take out the prepared nitric acid mixture, then the two-phase material is transported into the reactor through the corresponding metering tool, control the reaction temperature at 55℃, the mixture is one phase, the flow rate is 50mL / min-100mL / min, the flow rate of sulfuric acid as another phase material is 5-40mL / min, the residence time is 270s, the motor frequency is 30Hz, the final product is obtained, and the product is detected by HPLC. It is found that when the mixture flows into the reactor at a flow rate of 92mL / min and the sulfuric acid flows into the reactor at a flow rate of 19mL / min, the raw material conversion rate is as high as 98%, and the product accounts for 92%.

[0104] Example 14:

[0105] Effect of residence time on reaction:

[0106] A method for preparing 1-nitroanthraquinone by using a dynamic tubular reactor, comprising the following steps:

[0107] 1. Preparation of mixed solution: anthraquinone, dichloroethane and nitric acid are mixed in a ratio of 1:2:0.4 by mass for standby.

[0108] 2. Feeding: the mixed solution of anthraquinone, dichloroethane and nitric acid is fed into the reactor by peristaltic pump at room temperature as one phase, and sulfuric acid is transported into the reactor by horizontal flow pump at room temperature as another phase; adjust the ratio of two-phase raw materials.

[0109] 3. Heat exchange system: control the reaction temperature at 55℃ by using a cold and hot all-in-one machine during the reaction.

[0110] 4. Material ratio: anthraquinone:dichloroethane:nitric acid=1:2:0.4 by mass, anthraquinone:sulfuric acid=1:0.7 by mass.

[0111] 5. Residence time: when step 2 is carried out, the two-phase materials are mixed, the mixed solution is one phase, the flow rate is 50mL / min-100mL / min, and the flow rate of sulfuric acid as another phase material is 5-40mL / min.

[0112] Take 1700g anthraquinone, then add 3400g dichloroethane, nitric acid 680g, the prepared mixture is stored for standby, then take out the prepared nitric acid mixture, then the two-phase material is transported into the reactor through the corresponding metering tool, control the reaction temperature at 55℃, the mixture is one phase, the flow rate is 50mL / min-100mL / min, the flow rate of sulfuric acid as another phase material is 5-40mL / min, the residence time is 270s, the motor frequency is 30Hz, the final product is obtained, and the product is detected by HPLC. It is found that when the mixture flows into the reactor at a flow rate of 92mL / min and the sulfuric acid flows into the reactor at a flow rate of 19mL / min, the raw material conversion rate is as high as 98%, and the product accounts for 92%.

[0113] As used in this description, the term "example" means to serve as an instance of or to exhibit, and describes an embodiment thereof. As used in this description, the term "implementation" means to implement or to embody and describes one of the specific embodiments set forth herein. As used in this description, the term "embodiment" means an implementation or

[0114] Although the application has been described with reference to multiple illustrative embodiments, it will be understood that numerous modifications and variations can be made to the application without departing from the spirit and scope of the application. More particularly, variations and modifications are contemplated in terms of the subsystem components and / or layout of the subject combination layout. Further, other uses can be apparent to those of skill in the art.

Claims

1. A process for the preparation of 1-nitroanthraquinone using a dynamic tubular reactor, characterized in that, The method comprises the following steps: S1. Preparation of a mixed solution: mixing anthraquinone, dichloroethane and nitric acid, adjusting the content of dichloroethane according to experimental requirements, so that the mixed solution can enter a dynamic tubular reactor for reaction; S2. Feeding: the mixed solution of anthraquinone, dichloroethane and nitric acid is a phase, the mixed solution is a light yellow crystalline slurry, and is fed into the reactor at room temperature through a peristaltic pump, and sulfuric acid is another phase of material which is delivered into the reactor at room temperature through a horizontal flow pump; the ratio of the two phases of raw materials is adjusted, and the material ratio is mass ratio: anthraquinone:dichloroethane:nitric acid = 1:2:0.4; anthraquinone:sulfuric acid = 1:0.6-0.9, the mixed solution feeding flow rate is 50-100 mL / min, and the sulfuric acid feeding flow rate is 5-40 mL / min; S3. Heat exchange: temperature control is performed by using a heat exchange unit during the reaction, so that the reaction temperature is maintained at 30-60 DEG C; S4. Stopping: after the two phases of materials are mixed, the reaction is carried out under normal pressure; S5. Discharge: after the reaction stops for a certain time, the material is discharged from the dynamic tubular reactor; the residence time of the reaction is 60-360 s; The dynamic tubular reactor comprises a reactor body (1); the inside of the reactor body (1) comprises a mixing zone (2), a mass transfer zone (3) and a delay reaction zone (4); a heat exchange unit (5) is connected and arranged on the reactor body (1); a first material inlet (6) and a second material inlet (7) are arranged on the top of the reactor body (1); a mixing zone (2) is arranged on the top inside of the reactor body (1); a mixing baffle (8) is arranged on the bottom of the mixing zone (2); a first discharging channel (9) is arranged in the center of the mixing baffle (8); and the delay reaction zone (4) is arranged below the mixing zone (2); The mass transfer zone (3) comprises a first mass transfer zone (3.1) and a second mass transfer zone (3.2); the first mass transfer zone (3.1) is arranged around the outer wall of the delay reaction zone (4); the second mass transfer zone (3.2) is arranged in the center of the delay reaction zone (4); an outer heat transfer medium inlet (10) and an outer heat transfer medium outlet (11) are arranged on the first mass transfer zone (3.1); an inner heat transfer medium inlet (12) and an inner heat transfer medium outlet (13) are arranged on the second mass transfer zone (3.2); the outer heat transfer medium inlet (10) and the inner heat transfer medium inlet (12) are respectively connected with the outlet of the heat exchange unit (5); and the outer heat transfer medium outlet (11) and the inner heat transfer medium outlet (13) are respectively connected with the inlet of the heat exchange unit (5); The side wall of the reactor body (1) is provided with a product outlet (14); the product outlet (14) is provided with a product discharge channel (15); the second mass transfer zone (3.2) is provided in a cylindrical structure; the second mass transfer zone (3.2) is provided with a rotating shaft (16) in the center; the bottom of the rotating shaft (16) is connected with a rotating motor (17); the rotating motor (17) drives the overall rotating movement of the second mass transfer zone (3.2); the inner surface of the reactor body (1) is provided in a cylindrical structure; the rotating shaft (16) is arranged on the straight line of the central axis of the reactor body; a liquid reaction gap (18) is arranged between the outer surface of the second mass transfer zone (3.2) and the inner surface of the reactor body (1); the first material inlet (6), the second material inlet (7), the outer heat transfer medium inlet (10), the inner heat transfer medium inlet (12), the outer heat transfer medium outlet (11), the inner heat transfer medium outlet (13) and the product outlet (14) are provided with flow valves; further comprising a PLC controller (20), a temperature sensor; the temperature sensor is arranged inside the reactor body (1); the PLC controller (20) is arranged outside the reactor body (1); the temperature sensor is connected with the PLC controller (20); the flow valve is connected with the PLC controller (20); the rotating motor (17) is connected with the PLC controller (20); the width of the liquid reaction gap (18) is 1mm-5mm; the heat exchange unit (5) is provided as a cold and hot integrated machine; further comprising a viscosity sensor; the viscosity sensor is connected with the PLC controller (20).

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