CN110551406A

CN110551406A - alkaline violet 5BN alkalization process based on high-shear wet grinding

Info

Publication number: CN110551406A
Application number: CN201810546410.4A
Authority: CN
Inventors: 胡永辉
Original assignee: Fengcheng Sanyou Pen Making Technology Co Ltd
Current assignee: Fengcheng Sanyou Pen Making Technology Co Ltd
Priority date: 2018-05-31
Filing date: 2018-05-31
Publication date: 2019-12-10

Abstract

The invention relates to an alkalization method in a refining process of basic violet 5BN dye, wherein the method comprises the following steps: dispersing the crude product of the basic violet 5BN oxide material in water, and adding liquid alkali to adjust the pH of the system to be alkaline; the material is pulverized by a high-shear wet grinding process, so that the dispersion of the material in water is promoted, and the contact area of the material and alkali is increased; heating the pulverized material to 60-80 ℃ under the condition of stirring for alkalization reaction; adding sodium sulfide solution to convert copper ions into copper sulfide for removal; and (3) performing liquid-solid separation by standing, settling and removing supernatant liquid to obtain fine-particle alcohol color body precipitate. Compared with the traditional alkalization process, the method solves the problem of adhesion between material particles in the alkalization temperature rise process, can obtain alcohol color body sediment with lower fineness, and has the alkalization process temperature of only 60-80 ℃, so that the method is more energy-saving and efficient.

Description

Alkaline violet 5BN alkalization process based on high-shear wet grinding

Technical Field

The invention relates to the technical field of refining of basic dyes, in particular to an alkalization process in a refining process of basic violet 5BN dye, and specifically relates to a method for alkalization treatment of a basic violet 5BN crude product based on high-shear wet grinding and application thereof.

Background

The basic violet 5BN is a common basic dye, has the characteristics of strong dyeing capability, pure and bright color light, moderate price and the like, and has wide application in the fields of printing and dyeing, printing ink, medicine and the like.

The traditional production process of the basic violet 5BN comprises the processes of oxidative condensation, alkalization, acidification, salting out and the like. The oxidation condensation takes dimethylaniline as raw material, takes phenol and water as reaction medium, takes copper sulfate as reaction catalyst, takes sodium chloride as precipitating agent, and takes air or chemical oxidant for oxidation to generate the crude product of the basic violet 5 BN. Besides the basic violet 5BN product, the crude product also contains a large amount of phenol, copper, salt and other impurities, and the impurities seriously affect the product quality, so that the water-insoluble substance of the product exceeds the standard and the purity is low; in the fields of printing and dyeing, medicine and the like, the contained heavy metal copper ions also restrict the use safety of the product. Therefore, the copper removal and refining of the crude product have a key effect on improving the product quality and the use safety.

The refining process of the basic violet 5BN crude product mainly comprises the steps of alkalization, acidification, salting out and the like, wherein the alkalization is a key step of the refining process, the crude product is dispersed in water and is treated by sodium hydroxide and sodium sulfide, so that copper salt is converted into insoluble copper hydroxide and then is converted into insoluble copper sulfide to be removed, dye is also converted into an alcoloid body, and the specific reaction formula is shown in figure 1. In order to promote the alkalization reaction, materials wrapped in the crude product particles are melted out and fully react with alkali, the alkalization process generally needs to be heated to boiling, however, the crude product of the basic violet 5BN has the characteristics of precooling and hardening and adhesion when heated, the crude product is difficult to be completely dispersed in a water phase by the traditional alkalization process of the basic violet 5BN, the problem of material adhesion often occurs in the alkalization temperature rise process, and large particles generated by adhesion easily cause pipeline blockage, so that the material conveying is difficult; in severe cases, materials are completely adhered to the stirring paddle, so that equipment such as a motor and the like is damaged and production is interrupted, and the production stability of the refining process of the basic violet 5BN is severely restricted.

in order to solve the problem, some organizations at home and abroad provide some solutions. For example, the basic violet 5BN crude product is first ground and dispersed in water to promote dispersion of the crude product in water, but this method is only suitable for miniaturization test because the crude product is sensitive to temperature, and generally begins to soften at a temperature higher than 40 ℃, and the heat release caused by collision, friction and the like in general physical pulverization is inevitable, and the ground materials are bonded together after the temperature is raised. In the patent US 2,816,900, the scheme of dissolving materials by hot water and then converting copper into copper sulfide for removal is adopted, but the crude oxidized materials meet the hot water and are stuck together under the action of stirring, and the extremely large amount of hot water is consumed for completely dissolving the materials by the hot water. Patent CN 101381526A mentions that the yield is low due to excessive hardness of materials in the oxidation condensation process, the crude oxidation materials are treated by an organic solvent extraction method, the temperature is raised to 100 ℃ in the process, high-purity phenol-free basic purple with low copper content is obtained, but chlorobenzene and other organic solvents with high toxicity are introduced in the process, and additional processes such as solvent recovery are inevitably added.

Disclosure of Invention

the invention aims to overcome the defects of the prior art and provide a method for stably and efficiently carrying out the alkalization reaction of the crude basic violet 5 BN.

In order to achieve the above object, the basic violet 5BN alkalization process based on high shear wet milling of the present invention is as follows:

the invention discloses an alkaline violet 5BN alkalization process based on high-shear wet grinding, which is mainly characterized by comprising the following steps:

Dispersing the crude product of the basic violet 5BN oxide material in water, adding liquid alkali to adjust the pH of a system to be alkaline, pulverizing the material by a high-shear wet grinding process, heating the pulverized material to 60-80 ℃ under the stirring condition, preserving the heat for 0.5-3h, adding a sodium sulfide solution (the addition is that the sodium sulfide is slightly excessive and is tested by lead nitrate test paper), stirring for 1 h, standing and settling, discharging supernatant, washing for 1 time by clear water, standing and settling, and discharging the supernatant to obtain alcohol chromogen precipitate.

preferably, the water amount is 5-10 times of the mass of the oxide material;

The alkalization process system has PH of more than 12;

Preferably, the concentration of the liquid alkali is 30-50% (mass concentration);

The temperature of the system is controlled to be not higher than 40 ℃ in the high-shear wet grinding process;

preferably, the fine material obtained in the high shear wet grinding process has a particle size of less than 100 μm (D97);

preferably, the alkalization process temperature is 70 ℃;

preferably, the sodium sulfide solution is added dropwise.

The invention has the beneficial effects that:

(1) The high-shear wet grinding process is adopted, so that the crude oxide material can be dispersed in the water phase in a micron order, and the problem of material dispersion in the water phase is solved;

(2) because the particles are finer, the contact area between the crude oxidized material particles and the alkali is increased, the reaction degree of the materials and the alkali is further enhanced, and the adhesion between the particles is difficult in the alkalization temperature rise process;

(3) The crushed material and the alcohol color body obtained by alkalization have lower fineness, so that the material is easier to convey;

(4) Compared with the traditional alkalization process which needs boiling, the alkalization process only needs 60-80 ℃, the production efficiency is improved, and the energy consumption is greatly reduced.

Drawings

FIG. 1 is a reaction scheme of an alkalization process of basic violet 5 BN.

Detailed Description

in order to more clearly describe the technical contents of the present invention, the following further description is given in conjunction with specific embodiments. The invention relates to an alkaline violet 5BN alkalization process based on high-shear wet grinding, which mainly comprises the following steps of:

High-shear wet grinding can grind materials to micron level in water phase environment by means of high-speed rotation and shearing action;

The smaller the particle size of the particles is, the larger the specific surface area is, the larger the contact area with alkali is, and the more thorough the reaction is;

the copper impurities in the crude product are removed by conversion to copper sulphide, which is very insoluble in water (Ksp of only 1.27X 10 ^-36 at 25 ℃) and in dilute acid, and which maintains the copper content of the product at a low level.

the invention is further illustrated by the following three specific examples.

example 1:

Adding 400kg of massive crude oxidation materials obtained by oxidative condensation into 2000kg of water, adding 400kg of 30% (mass concentration) liquid alkali, grinding the materials to be less than 100 mu m (D97) through a high-shear wet grinding process, heating the ground materials to 70 ℃ under the stirring condition, preserving the heat for 2h, adding a sodium sulfide solution (the addition amount of sodium sulfide is tested by lead nitrate test paper), stirring for 1 h, standing, settling, discharging supernatant, washing for 1 time by clear water, standing, settling, and discharging the supernatant to obtain alcohol chromogen precipitate. The particle size of the obtained alcohol color bodies is shown in table 1 (particle size determined by laser particle sizer) compared to conventional processes.

TABLE 1 alcohol color body particle size

For the traditional alkalization process, the material fineness is generally more than 1000 μm, particles are easy to be adhered in the alkalization temperature rise process, the final alcohol color body particle size is generally more than 20000 μm, and spherical particles (the particle size is more than 5 cm) are generated frequently. For the alkaline violet 5BN alkalization process based on high-shear wet grinding, due to the good dispersion of crude oxidized material particles in an alkaline environment, the particle size of an alcohol color body is only about 220 mu m and is far smaller than that of the alcohol color body obtained by the traditional process, and meanwhile, the large-scale adhesion between the particles is avoided.

example 2:

Adding 400kg of massive crude oxidation materials obtained by oxidative condensation into 2000kg of water, adding 400kg of 30% (mass concentration) liquid alkali, pulverizing the materials to be below 50 mu m (D97) by a high-shear wet grinding process, heating the pulverized materials to 70 ℃ under the stirring condition, preserving the heat for 2h, adding a sodium sulfide solution (the addition amount of sodium sulfide is measured by lead nitrate test paper), stirring for 1 h, standing, settling, discharging supernatant, washing for 1 time by clear water, standing, settling, and discharging the supernatant to obtain alcohol chromogen precipitate. The particle size of the obtained alcohol color bodies is shown in table 2 (particle size determined by laser particle sizer) compared to the conventional process.

TABLE 2 alcohol color body particle size

Process for the preparation of a coating	Fineness of material (mum/D97)	adhesive block	Alcohol color body particle size (mum/D97)
				Conventional process	>1000	Is that	20000
Example 1	50	Whether or not	78

The high-shear wet grinding process is adopted to further reduce the particle fineness to 50 mu m, the alcohol color body granularity is only about 78 mu m and is far smaller than that obtained by the traditional process, and large-scale adhesion between particles is more difficult.

In this specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

Claims

1. an alkalization method of basic violet 5BN dye, which is characterized by comprising the following steps:

(1) Dispersing the crude product of the basic violet 5BN oxide material in water, and adding liquid alkali to adjust the pH of the system to be alkaline;

(2) pulverizing the materials by a high-shear wet grinding process;

(3) Heating the pulverized material to 60-80 ℃ under the stirring condition, and keeping the temperature for 0.5-3 h;

(4) Adding a sodium sulfide solution (the addition amount is that the sodium sulfide is slightly excessive and is tested by lead nitrate test paper), and stirring for 1 h;

(5) Standing, settling, removing supernatant, washing with clear water for 1 time, standing, settling, and removing supernatant to obtain alcoholic chromatid precipitate.

2. the method for alkalifying an alkaline violet 5BN dye according to claim 1, wherein the amount of water in step (1) is 5 to 10 times the mass of the oxidizing agent.

3. The method for alkalifying basic violet 5BN dye according to claim 1, wherein the system PH in step (1) is > 12.

4. The method for alkalizing basic violet 5BN dye according to claim 1, wherein the temperature of the high shear wet grinding process system in the step (2) is not higher than 40 ℃.

5. the method for alkalifying a basic violet 5BN dye according to claim 4, wherein the high shear wet milling process reduces the particle size of the material to below 100 μm (D97).