Bromine-containing disperse dye as well as preparation method and application thereof

Abstract

The invention provides a bromine-containing disperse dye as well as a preparation method and application thereof, and relates to the technical field of dyestuff, the preparation method of the bromine-containing disperse dye comprises the following steps: synthesizing 2, 4, 6-tribromoaniline series dyestuff by aniline, brominating by adopting a hydrogen peroxide process, diazotizing by adopting a one-pot method, and taking sulfuric acid as a system solvent, and the obtained filter cake can be further cyanided to replace bromine to obtain the bromine-containing disperse dye. And high-performance red, purple and blue filter cakes with high fastness and high strength are obtained. Sulfuric acid is adopted as a solvent in the bromination, diazotization and coupling steps, no redundant anions are introduced in a water-phase reaction, subsequent waste water resource utilization is facilitated, and the waste water utilization rate is increased.

Description

Technical Field

[0001] The present application relates to the technical field of dyes, and in particular to a bromine-containing disperse dye, a preparation method thereof, and an application thereof. Background Art

[0002] In the textile industry, the application of dyes is crucial. Disperse dyes are widely used in the dyeing and printing of polyester and its blended fabrics due to their simple molecular structure, small molecular weight and lack of water-soluble groups. However, the existing disperse dye technology still has many shortcomings, especially in terms of color fastness and dispersibility, there are obvious technical bottlenecks, and the wastewater utilization rate is low. Summary of the invention

[0003] The purpose of the present invention is to provide a bromine-containing disperse dye, a preparation method and an application thereof, wherein 2,4,6-tribromoaniline series dyes are synthesized by aniline, bromination is carried out by a hydrogen peroxide process, one-pot diazo is adopted, sulfuric acid is used as a system solvent, and the obtained filter cake can be further cyanated to replace bromine to obtain high-fastness, high-strength high-performance red, purple and blue filter cakes. The bromination, diazotization and coupling steps all use sulfuric acid as a solvent, and the aqueous phase reacts without the introduction of excess anions, which is convenient for the subsequent resource utilization of wastewater and improves the wastewater utilization rate.

[0004] In a first aspect, the present application provides a method for preparing a bromine-containing disperse dye, comprising the following steps: Step 1: using aniline as a starting material, using sulfuric acid of a certain concentration as a solvent, and preparing 2,4,6-tribromoaniline through a hydrogen peroxide bromination reaction with bromine or hydrobromic acid, wherein the obtained product is a tribromoaniline suspension containing sulfuric acid;

[0005] Step 2: After cooling the obtained tribromoaniline suspension containing sulfuric acid, a nitrosylsulfuric acid diazotizing agent is added dropwise, and the sulfuric acid in the reaction system of step 1 is also used as the diazotizing solvent in the second step. The reaction products are tribromoaniline diazonium sulfate and water. After the reaction is complete, the product is completely dissolved in sulfuric acid, and the obtained product is a clear solution of tribromoaniline diazonium sulfate;

[0006] Step 3: diluting the obtained clarified solution of tribromoaniline diazonium sulfate salt into ice water, carrying out coupling reaction with aromatic amine derivative coupling component, modifying different substituents on the benzene ring of the coupling component to change the conjugated system, thereby obtaining yellow, orange and red bromine-containing azo dye filter cakes with different absorption wavelengths, and the main product azo filter cake has almost no aqueous solution, and after solid-liquid separation, a solid dye filter cake and a liquid sulfuric acid solution are obtained respectively;

[0007] Step 4: The obtained solid dye filter cake is further subjected to cyanation to replace bromine to obtain red, purple and blue filter cakes.

[0008] In some specific embodiments, the method of preparing 2,4,6-tribromoaniline by bromination with aniline as a starting material and sulfuric acid of a certain concentration as a solvent through bromine or hydrobromic acid and hydrogen peroxide, wherein the obtained product is a tribromoaniline suspension containing sulfuric acid, comprises:

[0009] By using sulfuric acid as a solvent, a mixed solution of aniline and sulfuric acid is obtained;

[0010] Depending on the addition of bromine or hydrobromic acid, 2,4,6-tribromoaniline is obtained by bromination with hydrogen peroxide;

[0011] Low temperature control technology is used to ensure that the reaction is carried out at an appropriate temperature to prevent the occurrence of side reactions.

[0012] In some specific embodiments, the chemical formula of step 1 is expressed as follows:

[0013]

[0014] In some specific embodiments, the obtained tribromoaniline suspension containing sulfuric acid is cooled, and then a nitrosylsulfuric acid diazotizing agent is added dropwise, and the sulfuric acid in the reaction system of step 1 is also used as the diazotizing solvent in the second step, and the reaction product is tribromoaniline diazonium sulfate and water. After the reaction is complete, the product is completely dissolved in sulfuric acid, and the obtained product is a clear solution of tribromoaniline diazonium sulfate, including:

[0015] According to the obtained tribromoaniline suspension containing sulfuric acid, the temperature is lowered to reach a temperature condition suitable for diazotization reaction;

[0016] Nitrosyl sulfuric acid is used as a diazotizing agent and is added dropwise to a pre-cooled tribromoaniline suspension; the dropping rate and reaction temperature are controlled to ensure a smooth reaction;

[0017] A mixture of tribromoaniline diazonium sulfate and water is obtained, where the reactants are completely dissolved in sulfuric acid.

[0018] In some specific embodiments, the chemical formula of step 2 is expressed as follows:

[0019]

[0020] In some specific embodiments, the obtained clear solution of tribromoaniline diazonium sulfate is diluted into ice water, and a coupling reaction is carried out with an aromatic amine derivative coupling component, and different substituents are modified on the benzene ring of the coupling component to change the conjugated system to obtain yellow, orange, and red bromine-containing azo dye filter cakes with different absorption wavelengths, and the main reaction product azo filter cake has almost no aqueous solution, and after solid-liquid separation, a solid dye filter cake and a liquid sulfuric acid solution are obtained respectively, including:

[0021] According to the clarified solution of tribromoaniline diazonium sulfate salt, a reaction medium under a low temperature environment is obtained by diluting it into ice water;

[0022] Using aromatic amine derivatives as coupling components, changing the substituents on the benzene ring of the coupling components through coupling reactions;

[0023] By changing the substituents, yellow, orange and red bromine-containing azo dye filter cakes with different absorption wavelengths were obtained;

[0024] Obtaining the azo filter cake of the main reaction product, which is almost insoluble in water;

[0025] Through solid-liquid separation technology, the solid dye filter cake and liquid sulfuric acid solution are separated;

[0026] Further treatment with liquid sulfuric acid solution, by adjusting pH and temperature, to optimize the treatment of the residue in the solution;

[0027] High-efficiency filtration technology is used to ensure the purity and quality of solid dye filter cake.

[0028] In some specific embodiments, the chemical formula of step 3 is expressed as follows:

[0029]

[0030] X=H, CH3, NHCOCH3, NHCOC2H5

[0031] Y=H、OCH3

[0032] R1=C n H 2n+1 (n=2-3), C2H4CN, CH2COOCH3, C2H4OCOCH3, C2H4OCH3R2=C n H 2n+1 (n=2-3), CH2COOCH3, C2H4OCOCH3, C2H4OC2H4CN, C2H4OCH3, CH2-Ph.

[0033] In some specific embodiments, the chemical formula of step 4 is expressed as follows:

[0034] Z is Zn 2 + , Cu + Or Na + wait.

[0035] In a second aspect, an embodiment of the present application provides a bromine-containing disperse dye prepared using the above-mentioned preparation method.

[0036] In a third aspect, an embodiment of the present application provides an application of a bromine-containing disperse dye prepared by the above-mentioned preparation method in the field of textile dyeing.

[0037] The present invention provides a bromine-containing disperse dye, a preparation method and an application thereof. The 2,4,6-tribromoaniline series dyes are synthesized by aniline, bromination is carried out by a hydrogen peroxide process, one-pot diazo is adopted, and sulfuric acid is used as a system solvent. The obtained filter cake can be further cyanated to replace bromine to obtain high-fastness, high-strength, high-performance red, purple and blue filter cakes. The bromination, diazotization and coupling steps all use sulfuric acid as a solvent, and the aqueous phase reacts without the introduction of excess anions, which is convenient for subsequent wastewater resource utilization and improves wastewater utilization rate. In the entire process flow, sulfuric acid is not only used as a solvent, but also participates in multi-step reactions, which simplifies the operation steps, reduces the amount of solvent used, and improves the reaction efficiency. The present invention realizes the efficient preparation of dyes of various colors from aniline through reasonable process design, and has high industrial application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The figure is a process flow chart of the preparation method of bromine-containing disperse dyes. DETAILED DESCRIPTION

[0039] The embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0040] The following describes the embodiments of the present disclosure through specific examples, and those skilled in the art can easily understand other advantages and effects of the present disclosure from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. The present disclosure can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present disclosure. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present disclosure.

[0041] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein may be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present disclosure, it should be understood by those skilled in the art that an aspect described herein may be implemented independently of any other aspect, and two or more of these aspects may be combined in various ways. For example, any number of aspects described herein may be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein may be used to implement this device and / or practice this method.

[0042] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present disclosure. The drawings only show components related to the present disclosure rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0043] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects described may be practiced without these specific details.

[0044] The embodiment of the present invention provides a method for preparing bromine-containing disperse dyes, wherein the preparation method synthesizes 2,4,6-tribromoaniline series dyes from aniline, adopts sulfuric acid + hydrobromic acid (or bromine) + hydrogen peroxide process for bromination, adopts one-pot diazo, and uses sulfuric acid as the system solvent. The obtained filter cake can be further cyanated to replace bromine to obtain a variety of substituted dyes.

[0045] Technical features: Bromination, diazotization and coupling steps all use sulfuric acid as solvent, and the reaction is carried out in water phase without the introduction of excess anions, which facilitates the subsequent resource utilization of wastewater.

[0046] The preparation method of the present invention mainly includes four steps of bromination, diazotization, coupling and cyanation, which are specifically as follows:

[0047] Bromination step: 2,4,6-tribromoaniline is prepared by bromination reaction of hydrobromic acid and hydrogen peroxide using aniline as the starting material and sulfuric acid as the solvent. In this step, the reaction system is pure and no extra anions are introduced, which is convenient for subsequent treatment.

[0048] Diazotization step: After cooling the bromination product, nitrosyl sulfuric acid is added dropwise at low temperature to carry out diazotization reaction to obtain tribromoaniline diazonium sulfate. Sulfuric acid is used as both solvent and reaction medium in this step, which improves the reaction efficiency and product purity.

[0049] Coupling step: dilute the diazo solution into ice water and couple it with aromatic amine derivatives to obtain bromine-containing azo dyes. By adjusting the structure of the coupling components, dyes with different absorption wavelengths and color characteristics can be prepared.

[0050] Cyanidation step: After the coupling product is dissolved, a cyaniding agent is added to carry out a cyanidation reaction to obtain a cyano-substituted dye. The introduction of cyano further enhances the conjugation effect and color fastness of the dye.

[0051] Compared with the prior art, the high color fastness bromine-containing disperse dye of the present invention has the following significant advantages:

[0052] The color fastness is significantly improved, including sublimation fastness, washing fastness, sunlight fastness and perspiration fastness, etc., meeting the requirements of high-end textiles for dye performance.

[0053] Good dispersibility, the dye particles are evenly and stably dispersed in the water, improving the dyeing effect.

[0054] The preparation has strong stability. By optimizing the preparation process and adding stabilizers, the stability of the dye during storage and use is ensured.

[0055] Environmentally friendly and energy-saving, no toxic or harmful substances are discharged during the preparation process, and the wastewater resource utilization rate is high.

[0056] The following is a detailed description of the four steps of bromination, diazotization, coupling and cyanation, as follows:

[0057] Step 1: Bromination

[0058]

[0059] Aniline is used as the starting material, sulfuric acid of a certain concentration is used as the solvent, and 2,4,6-tribromoaniline is prepared by bromination reaction with bromine or hydrobromic acid + hydrogen peroxide. SO4 is removed from the system. 2- Without other anions, HBr is oxidized by hydrogen peroxide for bromination reaction. The reaction products are 2,4,6-tribromoaniline and water. Since the raw material is soluble in sulfuric acid and the product is suspended particles, the system has high separation degree, the raw material reaction conversion rate is more than 99% (HPLC tracking raw material), and the obtained product is a tribromoaniline suspension containing a certain concentration of sulfuric acid.

[0060] Here, sulfuric acid is used as a solvent to obtain a mixed solution of aniline and sulfuric acid. According to the addition of bromine or hydrobromic acid, 2,4,6-tribromoaniline is obtained through hydrogen peroxide bromination reaction. Gradient temperature control technology is used to ensure that the reaction is carried out at an appropriate temperature to prevent the occurrence of side reactions.

[0061] For example, under laboratory conditions, aniline can be dissolved in 98% concentrated sulfuric acid, and then an appropriate amount of bromine or hydrobromic acid is slowly added, and hydrogen peroxide is added dropwise under stirring. The initial reaction temperature is usually controlled between 0°C and 10°C and then gradually increased to 60-70°C to ensure a smooth reaction and avoid side reactions. After a period of reaction, 2,4,6-tribromoaniline is generated, which exists in the form of a suspension containing sulfuric acid. The key to this stage is to control the reaction conditions to ensure the formation of high yield and high purity products.

[0062] Exemplarily, in the process of preparing 2,4,6-tribromoaniline, aniline is first dissolved in concentrated sulfuric acid to form aniline sulfate. This step usually uses aniline and sulfuric acid mixed in a molar ratio of 1:1, for example, 10 mmoles of aniline are mixed with 10 mmoles of sulfuric acid. Then, bromine is slowly added to the solution, and the amount of bromine added is three times that of aniline, that is, 30 mmoles, to ensure complete bromination. To control the reaction conditions, the entire reaction is carried out at 0°C, and an ice water bath is used to maintain low temperature to prevent side reactions caused by temperature increase. During the bromination process, the color change and temperature of the solution are monitored in real time to adjust the addition rate of bromine to ensure the smooth progress of the reaction. After the reaction is completed, sulfuric acid is neutralized by dropping an alkaline solution, the pH is adjusted to neutral, and then the product is extracted using an organic solvent such as ether, and the solvent is removed by a rotary evaporator to obtain purified 2,4,6-tribromoaniline. Throughout the process, accurate chemical reagent addition and temperature control are achieved by using a computer-controlled titration device and a temperature sensor, thereby efficiently preparing the target compound.

[0063] Step 2: Diazotization

[0064]

[0065] The obtained tribromoaniline suspension containing sulfuric acid is cooled, and then a nitrosylsulfuric acid diazotizing agent is directly added dropwise at low temperature (generally 0-20° C.). The sulfuric acid in the first step (step 1) reaction system can also be used as a diazotizing solvent in the second step. The reaction products are tribromoaniline diazonium sulfate and water. After the reaction is completed, the product is completely dissolved in sulfuric acid. The reaction conversion rate of the raw material is more than 99% (HPLC tracking of the raw material). The obtained product is a clear solution of tribromoaniline diazonium sulfate.

[0066] Here, according to the obtained sulfuric acid-containing tribromoaniline suspension, by cooling treatment, a temperature condition suitable for diazotization reaction is reached. Nitrosyl sulfuric acid is used as a diazotizing agent and is added dropwise to the precooled tribromoaniline suspension. By controlling the dropwise acceleration rate and the reaction temperature, the reaction is ensured to proceed smoothly. A mixture of tribromoaniline diazonium sulfate and water is obtained, and at this time, the reactant is completely dissolved in sulfuric acid.

[0067] Exemplarily, in the process of preparing bromine-containing azo dyes, the tribromoaniline suspension containing sulfuric acid is first cooled to 5°C under a low temperature environment to achieve a temperature condition suitable for the diazotization reaction. Then, nitrosyl sulfuric acid is slowly added dropwise to the suspension, and the drop rate is controlled at 0.5 ml per minute, while the temperature of the reaction system is kept at no more than 20°C to ensure the smooth progress of the reaction. At this point, tribromoaniline is completely converted into tribromoaniline diazonium sulfate, and the formed mixture is completely dissolved in sulfuric acid.

[0068] Step 3: Coupling

[0069]

[0070] X=H, CH3, NHCOCH3, NHCOC2H5

[0071] Y=H、OCH3

[0072] R1=C n H 2n+1 (n=2-3), C2H4CN, CH2COOCH3, C2H4OCOCH3, C2H4OCH3

[0073] R2=C n H 2n+1 (n=2-3), CH2COOCH3, C2H4OCOCH3, C2H4OC2H4CN, C2H4OCH3, CH2-Ph.

[0074] The obtained tribromoaniline diazo sulfate solution is diluted into ice water and coupled with the aromatic amine derivative coupling component. Different substituents can be modified on the benzene ring of the coupling component to change the conjugated system to obtain yellow, orange and red bromine-containing azo dye filter cakes with different absorption wavelengths. The reaction by-product is mainly sulfuric acid. The reaction products and by-products of the whole system are relatively simple. The main product azo filter cake has almost no aqueous solution. After solid-liquid separation, solid dye filter cake and liquid sulfuric acid solution are obtained respectively.

[0075] Here, the reaction medium in a low temperature environment is obtained by diluting the clarified solution of tribromoaniline diazonium sulfate into ice water. Aromatic amine derivatives are used as coupling components, and the substituents on the benzene ring of the coupling components are changed through coupling reactions. By changing the substituents, yellow, orange, and red bromine-containing azo dye filter cakes with different absorption wavelengths are obtained. The main product of the reaction, the azo filter cake, is obtained, and the filter cake has almost no water solubility. The solid dye filter cake and the liquid sulfuric acid solution are separated by solid-liquid separation technology. The liquid dilute sulfuric acid solution is used for further treatment, and the treatment of the residue in the solution is optimized by adjusting the pH value and temperature. High-efficiency filtration technology is used to ensure the purity and quality of the solid dye filter cake.

[0076] Exemplary, in the process of preparing bromine-containing azo dyes, the clarified solution of tribromoaniline diazonium sulfate is first diluted into ice water to reduce the temperature of the reaction medium to 5 ° C, ensuring that the coupling reaction is carried out under low temperature conditions to improve the selectivity and yield of the reaction. Then, aromatic amine derivatives with different substituents are added to the reaction system, such as aromatic amines with methyl groups in the para position, and it can be observed that the absorption wavelength of the coupling product is red-shifted, thereby obtaining a red dye. By adjusting the type and position of the substituents in the aromatic amine derivatives, dye products of different colors can be obtained. After the coupling reaction is completed, the solid-liquid separation technology is used to separate the solid dye filter cake from the liquid sulfuric acid solution. The solid dye filter cake is efficiently filtered, such as using a filter membrane with a pore size of 2 microns to ensure the purity and yield of the filter cake.

[0077] Step 4: Cyanidation

[0078] Z=Zn 2 + , Cu + Or Na + wait.

[0079] Solid dye filter cakes can be further cyanided to replace bromine to obtain high-fastness, high-strength high-performance red, purple and blue filter cakes. Liquid sulfuric acid solution can be resource-utilized as by-products of high-purity ammonium sulfate and magnesium sulfate after neutralization, decolorization and concentration with liquid ammonia or alkaline earth metals.

[0080] Here, the cyanidation reaction is carried out using an appropriate cyaniding agent according to the chemical composition of the solid dye filter cake. By selecting appropriate cyanidation conditions, such as temperature and reaction time, the complete cyanidation reaction is ensured. The cyanided dye filter cake is obtained, which contains bromine atoms substituted by cyano groups, thereby changing the spectral characteristics and color of the dye.

[0081] After the tribromoaniline azo dye filter cake is dissolved in a solvent, it can be further prepared into a cyano-substituted dye filter cake by cyaniding with a cyaniding agent. The strong electron-withdrawing effect of the cyano group can enhance the conjugation effect of the system, and can further enhance the application performance of the dye to obtain red, purple and blue dyes with high dyeing strength, fastness and bright color.

[0082] Application examples:

[0083] Add 100g of prepared 70% sulfuric acid into a 500mL flask, cool to 10°C in an ice bath, add 18.6g of aniline dropwise, stir for 30 minutes after the addition, add 102g of 48% hydrobromic acid dropwise, keep the temperature below 35°C, add 75g of 27.5% hydrogen peroxide dropwise, control the temperature at 35-65°C to maintain the reaction until sampling and HPLC tracking detection: no aniline, monobromoaniline <0.5%, dibromoaniline raw material <1.5%.

[0084] The bromide solution was cooled to 10°C in an ice bath, and 63.5 g of 40% nitrosyl sulfuric acid was added dropwise. After the addition, the temperature was controlled at 20°C to maintain the reaction until the material was clarified. Samples were taken for HPLC external standard tracking detection: the total content of monobromoaniline + dibromoaniline raw materials + tribromoaniline was <1%.

[0085] Dilute the above diazo solution into 1200mL ice water, keep the dilution temperature below 2°C, add 2% aniline amount of fatty alcohol polyoxyethylene ether dispersant, add 99.5% N-ethyl-N-cyanoethyloxyethyl-m-toluidine (one of the structures) 46.5g, maintain the reaction for more than 5 hours after addition, and detect that the diazo solution has reacted completely. Heat the water bath to 60°C, filter, and wash the filter cake to neutrality.

[0086] 110 g of the dried orange-yellow dye cake was collected.

[0087]

[0088] Structure 1-1

[0089] The filtrate was collected and the pH was adjusted to 6.5 with aqueous ammonia, 0.5% of the total water volume of activated carbon was added for filtration and decolorization, and the filtrate was concentrated to more than 50% and filtered to obtain white ammonium sulfate solid.

[0090] The approximate structure of orange-yellow can be obtained by using the approximate method.

[0091]

[0092] Structure 1-2

[0093]

[0094] Structure 1-3

[0095]

[0096] Structure 1-4

[0097]

[0098] Structure 1-5

[0099] The brown-red approximate structure is

[0100]

[0101] Structure 1-6

[0102]

[0103] Structure 1-7

[0104]

[0105] Structure 1-8

[0106]

[0107] Structure 1-9

[0108]

[0109] Structure 1-10

[0110] Cyanide application examples:

[0111] In a 500mL dry flask, add 150g of DMAC, add 50g of the prepared structure 1-1 dye dry product, heat to 90℃ to dissolve, cool to 60℃, add 16g of 1:1 zinc cyanide + cuprous cyanide mixture, heat to 90-95℃ for 2 hours, cool to 60℃, add 120g of methanol, cool to 10℃, filter to obtain a filter cake, add 300g of 6% sulfuric acid solution, add 12g of hydrogen peroxide below 20℃, stir for 5 hours, filter, wash the filter cake until neutral, and obtain 35g of structure 6 cyanide filter cake. The obtained filter cake is mixed with dispersant MF in a ratio of 1:1 and sand-milled to obtain a bright red dye slurry.

[0112]

[0113] Structure 2-1

[0114] The approximate structure of orange-red to red-purple can be obtained by approximation method.

[0115]

[0116] Structure 2-2

[0117]

[0118] Structure 2-3

[0119]

[0120] Structure 2-4

[0121]

[0122] Structure 2-5

[0123] Blue-purple to blue-green structure

[0124]

[0125] Structure 2-6

[0126]

[0127] Structure 2-7

[0128]

[0129] Structure 2-8

[0130]

[0131] Structure 2-9

[0132]

[0133] Structure 2-10

[0134] The embodiment of the present invention provides a bromine-containing disperse dye prepared by the above-mentioned preparation method.

[0135] The embodiment of the present invention provides an application of a bromine-containing disperse dye prepared by the above-mentioned preparation method in the field of textile dyeing.

[0136] The present invention provides a bromine-containing disperse dye, a preparation method and an application thereof, wherein 2,4,6-tribromoaniline series dyes are synthesized by aniline, bromination is carried out by a hydrogen peroxide process, one-pot diazo is adopted, sulfuric acid is used as a system solvent, and the obtained filter cake can be further cyanated to replace bromine to obtain high-fastness, high-strength, high-performance red, purple and blue filter cakes. Sulfuric acid is used as a solvent in the bromination, diazotization and coupling steps, and the aqueous phase reacts without the introduction of redundant anions, which is convenient for subsequent wastewater resource utilization and improves the wastewater utilization rate.

[0137] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing bromine-containing disperse dyes, characterized in that: The steps include: Step 1: 2,4,6-tribromoaniline is prepared by bromination reaction of aniline as a starting material and sulfuric acid of a certain concentration as a solvent with bromine or hydrobromic acid through hydrogen peroxide, and the obtained product is a tribromoaniline suspension containing sulfuric acid; Step 2: After cooling the obtained tribromoaniline suspension containing sulfuric acid, a nitrosylsulfuric acid diazotizing agent is added dropwise, and the sulfuric acid in the reaction system of step 1 is also used as the diazotizing solvent in the second step. The reaction products are tribromoaniline diazonium sulfate and water. After the reaction is complete, the product is completely dissolved in sulfuric acid, and the obtained product is a clear solution of tribromoaniline diazonium sulfate; Step 3: diluting the obtained clarified solution of tribromoaniline diazonium sulfate salt into ice water, carrying out coupling reaction with aromatic amine derivative coupling component, modifying different substituents on the benzene ring of the coupling component to change the conjugated system, thereby obtaining yellow, orange and red bromine-containing azo dye filter cakes with different absorption wavelengths, and the main product azo filter cake has almost no aqueous solution, and after solid-liquid separation, a solid dye filter cake and a liquid sulfuric acid solution are obtained respectively; Step 4: The obtained solid dye filter cake is further subjected to cyanation to replace bromine to obtain red, purple and blue filter cakes.

2. The method for preparing bromine-containing disperse dyes according to claim 1, characterized in that: The method uses aniline as a starting material, sulfuric acid of a certain concentration as a solvent, and bromine or hydrobromic acid to prepare 2,4,6-tribromoaniline through a hydrogen peroxide bromination reaction, and the obtained product is a tribromoaniline suspension containing sulfuric acid, including: By using sulfuric acid as a solvent, a mixed solution of aniline and sulfuric acid is obtained; According to the addition of bromine or hydrobromic acid, 2,4,6-tribromoaniline is obtained by bromination with hydrogen peroxide; Low temperature control technology is used to ensure that the reaction is carried out at an appropriate temperature to prevent the occurrence of side reactions.

3. The method for preparing bromine-containing disperse dyes according to claim 2, characterized in that: The chemical equation of step 1 is expressed as follows:

4. The method for preparing bromine-containing disperse dyes according to claim 1, characterized in that: The obtained tribromoaniline suspension containing sulfuric acid is cooled, and then a nitrosylsulfuric acid diazotizing agent is added dropwise, the sulfuric acid in the reaction system of step 1 is simultaneously used as the diazotizing solvent in the second step, the reaction product is tribromoaniline diazonium sulfate and water, and after the reaction is complete, the product is completely dissolved in sulfuric acid, and the obtained product is a clear solution of tribromoaniline diazonium sulfate, including: According to the obtained tribromoaniline suspension containing sulfuric acid, the temperature is lowered to reach a temperature condition suitable for diazotization reaction; Nitrosyl sulfuric acid is used as a diazotizing agent and is added dropwise to a pre-cooled tribromoaniline suspension; the dropping rate and reaction temperature are controlled to ensure a smooth reaction; A mixture of tribromoaniline diazonium sulfate and water is obtained, where the reactants are completely dissolved in sulfuric acid.

5. The method for preparing bromine-containing disperse dyes according to claim 4, characterized in that: The chemical equation of step 2 is expressed as follows:

6. The method for preparing bromine-containing disperse dyes according to claim 1, wherein the clarified solution of the obtained tribromoaniline diazonium sulfate salt is diluted into ice water, and a coupling reaction is carried out with an aromatic amine derivative coupling component, and different substituents are modified on the benzene ring of the coupling component to change the conjugated system so as to obtain yellow, orange and red bromine-containing azo dye filter cakes with different absorption wavelengths, and the main reaction product azo filter cake is almost free of aqueous solution, and solid-liquid separation is performed to obtain a solid dye filter cake and a liquid sulfuric acid solution respectively, comprising: According to the clarified solution of tribromoaniline diazonium sulfate salt, a reaction medium under a low temperature environment is obtained by diluting it into ice water; Using aromatic amine derivatives as coupling components, changing the substituents on the benzene ring of the coupling components through coupling reactions; By changing the substituents, yellow, orange and red bromine-containing azo dye filter cakes with different absorption wavelengths were obtained; Obtaining the azo filter cake as the main product of the reaction, which has almost no aqueous solution; Through solid-liquid separation technology, the solid dye filter cake and liquid sulfuric acid solution are separated; Further treatment with liquid sulfuric acid solution, by adjusting pH and temperature, to optimize the treatment of the residue in the solution; High-efficiency filtration technology is used to ensure the purity and quality of solid dye filter cake.

7. The method for preparing bromine-containing disperse dyes according to claim 6, characterized in that: The chemical equation of step 3 is expressed as follows: X=H, CH3, NHCOCH3, NHCOC2H5 Y=H、OCH3 R1=C n H 2n+1 (n=2-3)、C2H4CN、CH2COOCH3、C2H4OCOCH3、C2H4OCH3 R2=C n H 2n+1 (n=2-3)、CH2COOCH3、C2H4OCOCH3、C2H4OC2H4CN、C2H4OCH3、 CH2-Ph.

8. The method for preparing bromine-containing disperse dyes according to claim 7, characterized in that: The chemical equation of step 4 is expressed as follows: Z is Zn 2+ , Cu + Or Na + .

9. A bromine-containing disperse dye prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the bromine-containing disperse dye prepared by the preparation method according to any one of claims 1 to 8 in the field of textile dyeing.

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