KR19980074906A - Recovery method of pulverized mixture for pigment grinding - Google Patents

Abstract

The present invention relates to a recovery method for recovering by using a spray dryer in order to recycle the pulverized mixture after being used for pulverizing the pigment raw material.

The method for recovering the pulverized mixture for pulverizing pigments according to the present invention comprises: (1) adding a water to a pigment pulverized mixture comprising salt, pigment and organic solvent; (2) a pigment filtration step of filtering out a pigment insoluble in water; And (3) a drying step of drying the water by introducing a filtrate mixture consisting of a mixture of water, salt, and an organic solvent as a filtrate after filtration into a spray dryer.

Therefore, the method of recovering the pulverized mixture using the spray dryer shows a higher recovery rate than the conventional distillation method, and furthermore, the recovered pulverized mixture can be reused directly in the pulverization process without additional treatment.

Description

Recovery method of pulverized mixture for pigment grinding

The present invention relates to a recovery method for recovering a pulverized mixture used for pulverizing the pigment raw material obtained immediately after the pigment synthesis, and more particularly, using a spray dryer to recycle the pulverized mixture after use in the pulverization of the pigment raw material. The present invention relates to a recovery method for recovery.

Pigments, especially phthalocyanine pigments, have high colorability, excellent heat resistance, chemical resistance and light resistance, and therefore have a wide range of uses in the color industry and their importance is increasing every year. Beta- copper phthalocyanine is usually obtained by using phthalic anhydride, urea, copper, or copper phthalonitrile and copper salt as a raw material and reacting at a high temperature of 180 ° C. or higher in a solvent-free or inert solvent such as nitrobenzene or trichlorobenzene. The obtained pigment raw material, especially beta-dongphthalocyanine pigment raw material, is synthesized, and then ground using a salt milling method using a conventional kneader and other similar equipment for purification and improvement of color expression product. The salt milling method is a pulverized mixture of sodium chloride having an ionic crystal structure as a grinding agent in an organic solvent having a viscosity of ethylene glycol or polyethylene glycol, such as diethylene glycol or polyethylene glycol, in a constant ratio of about 1: 5. And the pigment raw material to be pulverized are mixed, added to the kneader, kneaded and ground to be pigmented.

After the pigment grinding step, it is preferable that the pigments are collected by filtration from the pigment grinding mixture including the pulverized pigment, and the pulverized mixture used for pulverization is also recovered and reused, and a conventional recovery method for recovering these pulverized mixtures. As a distillation method was used.

In the conventional distillation method, water is added to a pigment pulverized mixture mixed with a pigment raw material, a salt, and an organic solvent to dissolve the salt, and a pigment is separated using a filter. Distillation to remove the water.

However, the salt contained in the pulverized mixture recovered by this distillation method has an initial particle size of several μm, but the crystal size is too large because it is recovered by crystallization through water distillation, and the crystal shape is also directly in the pigment grinding process. There was a problem that it is not suitable to use, and since the recovery rate of salt and organic solvent is also by distillation, the recovery rate at the initial recovery is maintained at 90% or more initially, but the recovery rate at the time of 3 to 4 repetitive recovery drops rapidly to 50 There was a problem of lowering below%. In addition, the recovery device itself has many problems such as frequent failure, wear of the equipment and aging, which causes a decrease in productivity. In addition, environmental pollution caused by the reprocessing of organic solvents or recovered salts lost during the distillation process is inevitable, and the process itself becomes complicated, and energy consumption is usually accompanied. It acted as a factor to lower the commerciality.

Therefore, there is a need to improve the method for recovering the pulverized mixture, and the present inventors have developed a new pulverized mixture recovery method capable of recovering the pulverized mixture used in the pigment pulverization process to complete the present invention.

An object of the present invention is to provide a recovery method for recovering a pulverized mixture after use for pigment grinding using a spray dryer.

1 is a scanning electron micrograph of the pulverized mixture obtained during the first recovery of the pulverized mixture for pulverizing the pigment according to the present invention.

2 is a scanning electron micrograph of the pulverized mixture obtained at the second recovery of the pulverized mixture for pulverizing the pigment according to the present invention.

3 is a scanning electron micrograph of the pulverized mixture obtained at the third recovery of the pulverized mixture for pulverizing the pigment according to the present invention.

4 is a scanning electron micrograph of the pulverized mixture obtained at the fourth recovery of the pulverized mixture for pulverizing the pigment according to the present invention.

5 is a scanning electron micrograph of the pulverized mixture obtained at the fifth recovery of the pulverized mixture for pulverizing the pigment according to the present invention.

6 is a scanning electron micrograph of the pulverized mixture obtained at the sixth recovery of the pulverized mixture for pulverizing the pigment according to the present invention.

Method for recovering the pulverized mixture for pigment grinding according to the present invention for achieving the above object, (1) a hydrolysis step of adding water to the pigment pulverized mixture comprising a salt, a pigment and an organic solvent; (2) a pigment filtration step of filtering out a pigment insoluble in water; And (3) a drying step of drying the water by introducing a filtrate mixture consisting of a mixture of water, salt, and an organic solvent as a filtrate after filtration into a spray dryer.

In the hydrolysis step of (1), the amount of the hydrolyzate may be an amount capable of completely dissolving the salt in the pigment grinding mixture, and preferably 0.1 to 3 times the pigment grinding mixture.

Drying in the drying step of (3) is made by hot air drying.

In the drying step (3), the inlet temperature of the spray dryer is 150 ° C or more, the outlet temperature is 90 ° C or less, and the pressure of the atomizer is within the range of 3 to 7 kg / cm ² , and the pressure of the atomizer is in the range of 1 to 3 bar. Within a range of 15 to 40 rpm.

Hereinafter, the present invention will be described in detail with reference to specific examples.

The method for recovering the pulverized mixture for pigment grinding according to the present invention comprises: (1) adding a water to a pigment pulverized mixture comprising a salt, a pigment and an organic solvent; (2) a pigment filtration step of filtering out a pigment insoluble in water; And (3) drying the filtrate mixture after filtration into a spray dryer to dry the moisture.

The hydrolysis step of (1) serves to dissolve the salt in the pigment milling mixture so that the insoluble pigment can be easily separated by filtration. In other words, the water-soluble salts are dissolved so that the water-soluble salts are dissolved so that the salts and pigments present in the solid phase in the above-mentioned pigment grinding mixture can be easily separated by filtration, and only the water-insoluble pigment remains in the solid phase. Only solid pigments can be separated from the organic solvents by filtration.

The amount of water added to the pigment pulverized mixture in the hydrolysis step (1), that is, the amount of water is preferably an amount capable of completely dissolving the salt in the pigment pulverized mixture, preferably 0.1 of the pigment pulverized mixture. To three times. If the amount of hydrolysis is less than 0.1 times, sufficient dissolution of the salt used in the grinding may not be achieved, and since the undissolved salt is filtered and mixed together with the pigment at the time of filtration of the pigment, the process of removing the salt from the pigment is not performed again. There may be a problem that must be done, and if the water is applied in excess of three times unnecessarily, there may be a problem that takes a lot of time and energy to remove the water from the spray dryer.

The pigment filtration step of (2) is a step of separating only the pigment remaining in the solid phase in the pigment pulverized mixture in which the salt is completely dissolved by water, thereby collecting only the pulverized pigment.

In the drying step of (3), the filtrate mixture after the pigment is filtered and separated in the pigment filtration step of (2) is introduced into a spray dryer to dry and remove moisture to recover a pulverized mixture mixed with only a salt and an organic solvent. To help.

In particular, the drying in the drying step of (3) by the spray dryer may be performed by hot air drying, which directs hot air to the filtrate mixture sprayed at a constant pressure through a nozzle in the spray dryer to hot air. By removing the moisture by the water is to remove the water from the filtrate mixture and to dry.

In particular, the inlet temperature of the spray dryer in the drying step (3) above 150 ℃, the outlet temperature is 90 ℃ or less, the pressure by the compressor within the range of 3 to 7kg / cm ² , the pressure of the atomizer 1 to 3bar The drying and the feed rate of the filtrate mixture is controlled to be within the range of 15 to 40rpm is carried out drying conditions, wherein the compressor, atomizer and the like are all used in the known spray dryers It can be easily understood by those skilled in the art.

The recovery method of the pulverized mixture for pulverizing the pigment according to the present invention may be repeated several times or more, and it has been found that the recovery rate of the pulverized mixture is not greatly reduced even by repetition.

Example 1

First Recovery of Grinding Mixture Using Spray Dryer

300 g of beta-dongphthalocyanine pigment material, 2,000 g of a mixed mixture of polyethylene glycol as an organic solvent and sodium chloride as a salt in a ratio of 1: 5 were charged to a conventional grinding kneader and treated at 110 to 120 ° C. for 7 hours. After pulverizing the pigment raw material, about 3 l of water was added to the extracted pigment pulverized mixture to dissolve sodium chloride, filtered to separate the water-insoluble pigment, washed with water and dried, and then the remaining filtrate was separately separated at the inlet temperature. 170 ℃, outlet temperature 81 ~ 84 ℃, pressurized by the compressor 5kg / cm ² , the pressure of the atomizer 2bar and the feed rate of the filtrate mixture is adjusted to 23rpm in a spray dryer that maintains the drying conditions made by spraying, spray drying A ground mixture containing sodium chloride and an organic solvent was recovered. Polyethylene glycol and sodium chloride in the recovered ground mixture were recovered. Measures the amount of each of the usual melting method of the acetone, and scanning electron microscopy; the appearance and state of the sodium chloride was observed by (SEM Scanning Electron Microscope).

As a result, the amount of the recovered pulverized mixture was measured as 1,936 g when the average of 10 batches (Batch) was measured to show a recovery of 96.8%, it was confirmed that the average particle diameter of the recovered beta- copper phthalocyanine is 7.23μm.

Example 2

Second Recovery of Grinding Mixture Using Spray Dryer

A pulverized mixture was recovered in the same manner as in Example 1 except that 2,000 g of the pulverized mixture recovered in Example 1 was used.

As a result, the amount of the recovered pulverized mixture was measured as 1,942 g when the average of nine batches (Batch) was measured, showing a recovery of 97.1%, it was confirmed that the average particle diameter of the recovered beta- copper phthalocyanine is 7.38μm.

Example 3

3rd recovery of grinding mixture using spray dryer

A pulverized mixture was recovered in the same manner as in Example 2, except that 2,000 g of the pulverized mixture recovered in Example 2 was used.

As a result, the amount of recovered pulverized mixture was measured as 1,960g when the average of eight batches (Batch) was measured to show a recovery of 98.0%, it was confirmed that the average particle diameter of the recovered beta- copper phthalocyanine is 7.15μm.

Example 4

Fourth Recovery of Grinding Mixture Using Spray Dryer

A pulverized mixture was recovered in the same manner as in Example 2, except that 2,000 g of the pulverized mixture recovered in Example 3 was used.

As a result, the amount of recovered pulverized mixture was measured as 1930g when averaging 7 batches, which showed a recovery of 96.5%, and the average particle diameter of the recovered beta-dongphthalocyanine was 7.42 μm.

Example 5

5th recovery of pulverized mixture using spray dryer

A pulverized mixture was recovered in the same manner as in Example 2 except that 2,000 g of the pulverized mixture recovered in Example 4 was used.

As a result, the amount of the recovered pulverized mixture was measured as 1,944 g when the average of six batches (Batch) was measured to show a recovery of 97.2%, it was confirmed that the average particle diameter of the recovered beta-dongphthalocyanine is 6.36μm.

Example 6

6th Recovery of Grinding Mixture Using Spray Dryer

A pulverized mixture was recovered in the same manner as in Example 2, except that 2,000 g of the pulverized mixture recovered in Example 5 was used.

As a result, the amount of the recovered pulverized mixture was measured as 1,926 g when the average of five batches (Batch) was measured, showing a recovery of 96.3%, it was confirmed that the average particle diameter of the recovered beta- copper phthalocyanine is 7.81μm.

Based on the results of Examples 1 to 6 above, the pulverized mixture by the method of recovering the pulverized mixture for pulverizing the pigment according to the present invention can always be recovered with a high recovery rate of 96% or more even if the recovery is repeated In addition, it was confirmed that the recovered pulverized mixture can be directly used in the pigment pulverization process as it is recovered without reprocessing.

In addition, as a quality test of the pigment obtained by reuse of the recovered pulverized mixture in the pulverization of the pigment raw material, there is a significant difference from the pigment obtained by using the pulverized mixture first used in the printing ink test, paint test, and plastic test. I could not see it. In addition, it was confirmed that the same or similar results as shown in Tables 1 and 2 in the Color Strength Test and the heat resistance test.

TABLE 1

Paint testing Plastic testing Comparative product 100.00 100.00 Example 1 90.01 87.36 Example 2 94.01 93.14 Example 3 87.73 81.55 Example 4 103.99 105.87 Example 5 100.01 101.46 Example 6 102.22 104.68 The comparative product above is the original milled mixture before reuse

TABLE 2

Comparative product test Example 5 Standard 100.00 102.11 150 ℃ 99.84 101.60 180 ℃ 96.78 100.41 210 ℃ 98.87 101.29 240 ℃ 100.14 101.41 270 ℃ 97.76 100.36 300 ℃ 89.93 87.57 330 ℃ 84.74 88.05 The comparative product above is the original milled mixture before reuse

In particular, in the case of Table 2, in the heat resistance test, rather, the pulverized mixture recovered and used was shown to have a somewhat better effect.

In addition, even in the storage test, the coloring was mixed with xylene and left in the air.

Therefore, according to the present invention, the method of recovering the pulverized mixture using the spray dryer shows a higher recovery rate than the conventional distillation method, and furthermore, the recovered pulverized mixture can be directly reused in the pulverization process without additional treatment. .

Although the present invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical scope of the present invention, and such modifications and modifications are within the scope of the appended claims.

Claims (5)

(1) a hydrolysis step of adding water to a pigment pulverized mixture comprising a salt, a pigment and an organic solvent; (2) a pigment filtration step of filtering out a pigment insoluble in water; And (3) Drying step of drying the filtrate mixture consisting of water, salt and organic solvent as a filtrate after filtration into a spray dryer to dry the moisture Method for recovering the pulverized mixture for grinding the pigment, characterized in that consisting of. The method of claim 1, The method of claim 1, wherein the amount of the hydrolyzate in the hydrolysis step (1) is such that the salt in the pigment grinding mixture can be completely dissolved. The method of claim 2, The method of claim 1, wherein the amount of the hydrolyzate in the hydrolysis step of (1) is 0.1 to 3 times the pigment grinding mixture. The method of claim 1, The method for recovering the pulverized mixture for pigment grinding, characterized in that the drying in the drying step of (3) is performed by hot air drying. The method of claim 1, In the drying step (3), the inlet temperature of the spray dryer is 150 ° C or more, the outlet temperature is 90 ° C or less, and the pressure of the atomizer is within the range of 3 to 7 kg / cm ² , and the pressure of the atomizer is in the range of 1 to 3 bar. Within and and the feed rate of the filtrate mixture is recovered in the drying conditions made to be within the range of 15 to 40rpm.