CN117924040A - Method for recovering 2,4, 6-tricresyl from 2, 6-xylenol raffinate - Google Patents

Abstract

The invention relates to the technical field of separation and purification, in particular to a method for recovering 2,4, 6-tricresyl from 2, 6-xylenol raffinate, which comprises the following steps: cooling the 2, 6-xylenol raffinate to 15+/-1 ℃, preserving heat for 10-40 min, and then blowing out liquid materials by adopting compressed gas; heating and melting the crystallized solid material, preserving heat for 0-40 min, cooling to 30+/-1 ℃, preserving heat for 10-40 min, and blowing out the liquid material by adopting compressed gas; heating and melting the crystallized solid material, preserving heat for 0-40 min, cooling to 40-45 ℃, preserving heat for 10-40 min, and blowing out the liquid material by adopting compressed gas; and (3) heating and melting the crystallized solid material, and discharging to obtain the 2,4, 6-tricresyl. The invention obviously improves the recovery rate and purity of the 2,4, 6-tricresyl by sectionally and repeatedly melting and crystallizing and blowing out liquid materials through compressed gas.

Description

Method for recovering 2,4, 6-tricresyl from 2, 6-xylenol raffinate

Technical Field

The invention relates to the technical field of separation and purification, in particular to a method for recovering 2,4, 6-tricresyl from 2, 6-xylenol raffinate.

Background

English name of 2,4, 6-tricresol: 2,4,6-Trimethylphenol, molecular formula: C9H12O, molecular weight: 136.19. boiling point: 220 ℃, melting point: 70-72 ℃ and the density 0.9809. Is a white or beige crystalline powder with strong phenolic taste, slightly soluble in water, and soluble in methanol, diethyl ether, chloroform, etc. The structural formula is as follows:

2,4, 6-trimethylphenol is mainly used as an intermediate for synthesizing vitamin E, and 2,3, 6-trimethylaniline (raw materials for synthesizing dyes, pigments, medicaments, binders and the like) can also be used as an additive of epoxy resin. The method for synthesizing 2,4, 6-tricresyl mainly comprises the following steps: 1) The p-cresol and methanol react at the high temperature of the catalyst to prepare the catalyst; 2) 2, 4-xylenol reacts with methanol at high temperature of the catalyst. However, these methods are all produced by raw materials, and the production cost and the material cost are also high.

2,4, 6-Trimethylphenol is a major by-product in the alkylation of phenol with methanol to produce o-cresol and 2, 6-xylenol. After the o-cresol and the 2, 6-xylenol are purified by a distillation tower, the main component of the residual liquid at the bottom of the tower is 2,4, 6-trimethylphenol, and the content is 60-70 percent. The other components comprise 2, 6-xylenol (melting point 43-45 ℃), 2, 4-xylenol (melting point 26 ℃), 2, 5-xylenol (melting point 75-77 ℃), 2,3, 6-tricresyl (melting point 59-62 ℃) and a plurality of impurities such as ether peaks, and the purification difficulty of the 2,4, 6-tricresyl is increased.

The purification method in the prior art mainly comprises the following steps: 1) Distilling with a distillation column; 2) A recrystallization method. Distilling with a distillation tower, wherein low boiling point substances of 2, 6-xylenol, 2, 4-xylenol, 2, 3-xylenol and 2, 5-xylenol are completely removed, and 2,4, 6-tricresyl is distilled out of residual liquid, and the boiling point of 2,4, 6-tricresyl and 2,3, 6-tricresyl are similar, so that the product is difficult to reach more than 99 percent; the recrystallization method requires addition of a solvent, and thus also requires recovery of the solvent, resulting in large energy consumption and thus low yield.

Accordingly, there is a need to provide an improved process for recovering 2,4, 6-tricresyl from 2, 6-xylenol raffinate to increase yield and purity while reducing energy consumption.

Disclosure of Invention

The invention aims to provide a method for recovering 2,4, 6-tricresyl from 2, 6-xylenol raffinate, which is characterized in that the recovery rate and purity of 2,4, 6-tricresyl are remarkably improved by carrying out segmented and repeated melting crystallization and blowing out liquid materials through compressed gas.

In order to achieve the above object, the present invention provides a method for recovering 2,4, 6-tricresyl from a 2, 6-xylenol raffinate, comprising the steps of:

S1, cooling the 2, 6-xylenol raffinate to 15+/-5 ℃, preserving heat for 10-40 min, and then blowing out liquid materials by adopting compressed gas;

S2, heating and melting the solid material crystallized in the step S1, preserving heat for 0-40 min, then cooling to 30+/-5 ℃, preserving heat for 10-40 min, and then blowing out the liquid material by adopting compressed gas;

S3, heating and melting the solid material crystallized in the step S2, preserving heat for 0-40 min, then cooling to 40+/-5 ℃, preserving heat for 10-40 min, and then blowing out the liquid material by adopting compressed gas;

And S4, heating and melting the solid material crystallized in the step S3, and discharging to obtain the 2,4, 6-tricresyl.

The melting points of materials with different impurity contents are utilized to carry out segmented multiple melting crystallization, and meanwhile, compressed gas is adopted to fully blow out liquid materials after each crystallization, so that liquid impurities mixed in the crystals can be taken away as much as possible, and the purity of the finally obtained 2,4, 6-tricresyl can be improved. Meanwhile, the invention does not need to add extra solvent, thereby not only reducing the consumption of raw materials, but also reducing the loss of 2,4, 6-tricresyl and improving the yield.

Further, the components of the 2, 6-xylenol raffinate mainly comprise 2, 6-xylenol, 2, 4-xylenol, 2, 3-xylenol, 2,4, 6-tricresyl and 2,3, 6-tricresyl; in some embodiments, the composition of the 2, 6-xylenol raffinate also includes other impurities such as ethers. Wherein the mass content of the 2,4, 6-tricresyl is 60-75%, preferably 60-70%. The invention is particularly suitable for recovering 2,4, 6-tricresyl from 2, 6-xylenol raffinate in this content range.

Further, the mass content of the 2, 6-xylenol is 0-1.5%, preferably 0.5-1%; the mass content of the 2, 4-xylenol is 0-30%, preferably 10-25%; the mass content of the 2, 3-xylenol is 0-5%, preferably 1-4%; the mass content of the 2,3, 6-tricresyl is 0-15%.

Further, in the step S1, the temperature of the 2, 6-xylenol raffinate before cooling is more than or equal to 70 ℃, preferably 70+/-1 ℃; and/or, in the steps S2 to S4, the end temperature of heating and melting is more than or equal to 70+/-1 ℃.

In the step S1, cooling is carried out by introducing cooling water at 15+/-5 ℃; preferably 15.+ -. 1 ℃.

In the step S2, cooling is carried out by introducing cooling water with the temperature of 30+/-5 ℃, and the temperature is preferably 30+/-1 ℃;

in step S3, the temperature is reduced by introducing cooling water at 40+ -5deg.C, preferably 40+ -1deg.C. The invention has fast cooling rate, so the purification efficiency is high.

Further, steps S1 to S4 are all carried out in a melt crystallizer, wherein the melt crystallizer comprises a tube side, a shell side and a jacket, circulating cooling water is introduced into the tube side and the jacket, and the shell side is introduced into the 2, 6-xylenol raffinate.

Further, the gauge pressure of the compressed gas is 0.002-0.05Mpa, preferably 0.01-0.05 Mpa; the liquid material is carried out by the strong pressure, which is helpful for reducing the impurity content.

Further, the compressed gas is one or more of compressed air, nitrogen and inert gas.

Further, the method comprises the following steps:

s1, adding 2, 6-xylenol raffinate above 70 ℃ into a crystallizer, introducing cooling water at 15+/-1 ℃ to keep the temperature of the 2, 6-xylenol raffinate at 15+/-1 ℃ for 20-35 min, and then blowing out liquid materials by adopting compressed gas until no materials flow out from a discharge port;

S2, introducing hot water with the temperature of more than 70 ℃, heating and melting the solid material crystallized in the step S1, preserving heat for 0-40 min, then introducing cooling water with the temperature of 30+/-1 ℃ to ensure that the molten material is preserved for 20-35 min at the temperature of 30+/-1 ℃, and then blowing out the liquid material by adopting compressed gas until no material flows out of a discharge hole;

S3, introducing hot water with the temperature of more than 70 ℃, heating and melting the solid material crystallized in the step S2, preserving heat for 0-40 min, then introducing cooling water with the temperature of 40+/-5 ℃, preferably 40+/-1 ℃, preserving heat for 10-40 min, and then blowing out the liquid material by adopting compressed gas until no material flows out of a discharge port;

s4, introducing hot water with the temperature of more than 70 ℃, and discharging after the heating value of the solid material crystallized in the step S3 is completely melted, so as to obtain 2,4, 6-tricresyl.

Further, the liquid material collected in the step S1 accounts for 20-30% of the mass of the 2, 6-xylenol raffinate, wherein the mass content of the 2,4, 6-xylenol is below 42% of the liquid material;

and/or the liquid material collected in the step S2 is 0-10% of the mass of the 2, 6-xylenol raffinate, wherein the mass content of the 2,4, 6-xylenol is below 35% of the liquid material;

And/or the liquid material collected in the step S3 is 0-10% of the mass of the 2, 6-xylenol raffinate, wherein the mass content of the 2,4, 6-xylenol is less than 45% of the liquid material.

Further, the purity of the 2,4, 6-tricresyl obtained in the step S4 is more than or equal to 98%, and the yield is more than or equal to 50%, preferably more than or equal to 55%.

The beneficial effects of the invention are as follows:

according to the method for recovering 2,4, 6-tricresyl from the 2, 6-xylenol raffinate, provided by the invention, the liquid material is forcefully blown out through segmented repeated melting crystallization and compressed gas, so that the recovery rate and purity of the 2,4, 6-tricresyl are obviously improved, meanwhile, the energy conservation and carbon reduction are also realized, and the recovery efficiency is improved.

Drawings

In order to more clearly illustrate the invention or the technical solutions of the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the invention, and other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a diagram of the cooling and warming process of the process for recovering 2,4, 6-trimethylphenol from a 2, 6-xylenol raffinate provided in the examples;

FIG. 2 is a schematic diagram of a structure of a crystallizer employed in the present invention;

FIG. 3 is a chromatogram of the final melt of example 1.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the technical solutions in the present invention will be clearly and completely described below, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The invention aims to provide a method for recovering 2,4, 6-tricresyl in 2, 6-xylenol raffinate, which is simple and feasible and can reduce the energy consumption of production. The method specifically comprises the following steps:

(1) Adding the 2, 6-xylenol raffinate with the temperature of more than 70 ℃ into a crystallization kettle, cooling to 15 ℃, preserving heat for 30min, and closing an emptying valve. And opening a bottom valve, and pressing in the bottom valve from the upper part of the material by using 0.05MPa compressed air until no material flows out of a discharge hole.

(2) Closing the bottom valve, heating the material to 70 ℃ again, adding the material into the crystallization kettle, cooling to 30 ℃, preserving heat for 30min, and closing the emptying valve. And opening a bottom valve, and pressing in the bottom valve from the upper part of the material by using 0.05MPa compressed air until no material flows out of a discharge hole.

(3) Closing the bottom kettle, heating the material to 70 ℃ again, adding the material into the crystallization kettle, cooling to 45 ℃, preserving heat for 30min, and closing the emptying valve. Opening the bottom kettle, and pressing in the kettle from the upper part of the material by using 0.05MPa compressed air until no material flows out from the discharge port.

(4) And (5) heating the material to 70 ℃ to be completely melted, opening a bottom valve and discharging to obtain a finished product.

As shown in figure 2, the crystallizer used in the method is a heat exchanger with good heat exchange effect, the tube side and the jacket are circulating cooling water, the shell layer is a material phase, and the tube side is a cooling water phase.

In fig. 2, a is a feed inlet, B is a discharge outlet, C is a water inlet, D is a water outlet, E is a tube side water inlet, and F is a thermometer port.

The invention combines the column temperature 145 ℃, the detector and sample injection temperature 260 ℃, the nitrogen pressure 0.29MPa, the air pressure 0.4, the hydrogen pressure 0.2MPa and the column model Agilent DB-5 method to carry out qualitative and quantitative analysis on each component, and specific examples are as follows.

Example 1

A process for recovering 2,4, 6-trimethylphenol from a2, 6-xylenol raffinate comprising the steps of:

TABLE 1 content of 2, 6-xylenol raffinate component

Step one

690.00 G of 2, 6-xylenol raffinate at 80℃were fed into a crystallization kettle. And (3) introducing cooling water at 15 ℃ into the tube array, preserving heat for 30min, and closing the emptying valve. Opening the bottom kettle, and pressing in the kettle from the upper part of the material by using 0.05MPa compressed air until no material flows out from the discharge port. 181.30 g of extrudate are pressed out.

TABLE 2 ingredient content of extrudate

Step two

Closing the bottom valve, opening the emptying valve, introducing hot water at 70 ℃ into the tube array, preserving heat for 30min, and closing the emptying valve. Cooling water at 30 ℃ is introduced into the tube array, the temperature is kept for 30min, and the emptying valve is closed. The bottom kettle is opened, and 0.05MPa nitrogen is used for pressing in from the upper part of the material until no material flows out from the discharge port. 154.00 g of extrudate are pressed out.

TABLE 3 ingredient content of extrudate

Step three

Closing the bottom valve, opening the emptying valve, introducing hot water at 70 ℃ into the tube array, preserving heat for 30min, and closing the emptying valve. And (3) introducing 40 ℃ cooling water into the tube array, preserving heat for 30min, and closing the emptying valve. Opening the bottom kettle, and pressing in the kettle from the upper part of the material by using 0.05MPa compressed air until no material flows out from the discharge port. The extrudate was 54.00 g.

TABLE 4 ingredient content of extrudate

And (3) opening a bottom valve, closing an emptying valve, introducing hot water at 70 ℃ into the tube array, and preserving heat for 30min to melt materials in the crystallization kettle. 245.10 g of a material were obtained.

TABLE 5 ingredient content of the materials

It can be seen that the content of 2,4, 6-tricresyl in the finally obtained material is up to more than 98%.

Example 2

A process for recovering 2,4, 6-trimethylphenol from a2, 6-xylenol raffinate comprising the steps of:

TABLE 6 content of 2, 6-xylenol raffinate component

Step one

690.00 G of 2, 6-xylenol raffinate at 85℃were fed into a crystallization kettle. And (5) introducing cooling water at 15 ℃ into the tube array, preserving heat for 40min, and closing the emptying valve. Opening the bottom kettle, and pressing in the kettle from the upper part of the material by using 0.05MPa compressed air until no material flows out from the discharge port. 180.90 g of extrudate.

TABLE 7 ingredient content of extrudate

Step two

Closing the bottom valve, opening the emptying valve, introducing hot water at 70 ℃ into the tube array, preserving heat for 30min, and closing the emptying valve. Cooling water at 30 ℃ is introduced into the tube array, the temperature is kept for 30min, and the emptying valve is closed. Opening the bottom kettle, and pressing in the kettle from the upper part of the material by using 0.06MPa air until no material flows out from the discharge port. 156.00 g of extrudate are pressed out.

TABLE 8 ingredient content of extrudate

Step three

Closing the bottom valve, opening the emptying valve, introducing hot water at 70 ℃ into the tube array, preserving heat for 30min, and closing the emptying valve. And (3) introducing 40 ℃ cooling water into the tube array, preserving heat for 30min, and closing the emptying valve. Opening the bottom kettle, and pressing in the kettle from the upper part of the material by using 0.05MPa compressed air until no material flows out from the discharge port. 53.00 g of extrudate.

TABLE 9 ingredient content of extrudate

And (3) opening a bottom valve, closing an emptying valve, introducing hot water at 75 ℃ into the tube array, and preserving heat for 30min to melt materials in the crystallization kettle. 243.80 g of a material were obtained.

TABLE 10 ingredient content of materials

Example 3

A process for recovering 2,4, 6-trimethylphenol from a2, 6-xylenol raffinate comprising the steps of:

TABLE 11 content of 2, 6-xylenol raffinate component

Step one

690.00 G of 2, 6-xylenol raffinate at 75℃were fed to a crystallization kettle. And (3) introducing cooling water at the temperature of 19 ℃ into the tube array, preserving heat for 35min, and closing the emptying valve. Opening the bottom kettle, and pressing in the kettle from the upper part of the material by using 0.04MPa compressed air until no material flows out from the discharge port. 181.00 g of extrudate are pressed out.

TABLE 12 ingredient content of extrudate

Step two

Closing the bottom valve, opening the emptying valve, introducing 72 ℃ hot water into the tube array, preserving heat for 30min, and closing the emptying valve. Cooling water at 28 ℃ is introduced into the tube array, the temperature is kept for 30min, and the emptying valve is closed. The bottom kettle is opened, and 0.05MPa nitrogen is used for pressing in from the upper part of the material until no material flows out from the discharge port. 155.00 g of extrudate.

TABLE 13 ingredient content of extrudate

Step three

Closing the bottom valve, opening the emptying valve, introducing hot water at 73 ℃ into the tube array, preserving heat for 30min, and closing the emptying valve. And (3) introducing 41 ℃ cooling water into the tube array, preserving heat for 30min, and closing the emptying valve. And opening the bottom kettle, and pressing in the bottom kettle from the upper part of the material by using 0.06MPa nitrogen until no material flows out from the discharge port. 54.30 g of extrudate are pressed out.

TABLE 14 ingredient content of extrudate

And (3) opening a bottom valve, closing an emptying valve, introducing hot water at 75 ℃ into the tube array, and preserving heat for 30min to melt materials in the crystallization kettle. 244.30 g of a material were obtained.

TABLE 15 ingredient content of materials

From examples 1-3, it can be seen that the final yield and purity of 2,4, 6-tricresyl are not very different when the raw materials are subjected to three recovery experiments, which illustrates the feasibility and stability of the recovery method of the invention, and is convenient for practical application.

Comparative example 1

A process for recovering 2,4, 6-trimethylphenol from a2, 6-xylenol raffinate comprising the steps of:

TABLE 16 content of 2, 6-xylenol raffinate component

Step one

Other conditions are unchanged except that compressed air is not used. 690.00 g of 2, 6-xylenol raffinate at 85℃were fed into a crystallization kettle. And (5) introducing cooling water at 15 ℃ into the tube array, preserving heat for 40min, and closing the emptying valve. The bottom kettle was opened and 62.30 g of liquid material was discharged.

TABLE 17 ingredient content of materials

Step two

Other conditions are unchanged except that compressed air is not used. Closing the bottom valve, opening the emptying valve, introducing hot water at 70 ℃ into the tube array, preserving heat for 30min, and closing the emptying valve. Cooling water at 30 ℃ is introduced into the tube array, the temperature is kept for 30min, and the emptying valve is closed. The bottom kettle is opened, and 160.30 g of liquid material is discharged.

TABLE 18 ingredient content of materials

Step three

Other conditions are unchanged except that compressed air is not used. Closing the bottom valve, opening the emptying valve, introducing hot water at 70 ℃ into the tube array, preserving heat for 30min, and closing the emptying valve. And (3) introducing 40 ℃ cooling water into the tube array, preserving heat for 30min, and closing the emptying valve. The bottom kettle is opened, and 58.21 g of liquid material is discharged.

TABLE 19 composition content of materials

And (3) opening a bottom valve, closing an emptying valve, introducing hot water at 75 ℃ into the tube array, and preserving heat for 30min to melt materials in the crystallization kettle. Yield 297.3 g.

TABLE 20 ingredient content of materials

As can be seen from comparative example 1, when the natural discharge is carried out after each melt crystallization, the total discharge amount of the melt crystallization is remarkably reduced without using compressed gas, wherein the content of entrained 2,4, 6-trimethylphenol is increased because the material between crystals cannot be smoothly discharged due to the surface tension of the material with a lower melting point, thereby resulting in a higher impurity content in the finally obtained material and a lower purity of 2,4, 6-trimethylphenol.

In summary, the invention sequentially carries out melt crystallization at three groups of temperatures of 15+/-5 ℃, 30+/-5 ℃ and 40+/-5 ℃, in the process, 2,4, 6-tricresol is relatively high in component, and is crystallized and separated out firstly in the process of cooling, but 2,4, 6-tricresol which does not form crystals forms eutectic materials with lower melting point and materials with higher melting point into a liquid form. The compressed gas is pressed in from the upper part of the material, so that the liquid material in the gaps of the crystals can be completely pressed out effectively, the impurity content is reduced as much as possible, and finally, the 2,4, 6-tricresyl with the purity of more than 98 percent can be obtained through three gradient melting crystallization operations.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (9)

1. A process for recovering 2,4, 6-trimethylphenol from a2, 6-xylenol raffinate comprising the steps of:

S1, cooling the 2, 6-xylenol raffinate to 15+/-5 ℃, preserving heat for 10-40 min, and then blowing out liquid materials by adopting compressed gas;

S2, heating and melting the solid material crystallized in the step S1, preserving heat for 0-40 min, then cooling to 30+/-5 ℃, preserving heat for 10-40 min, and then blowing out the liquid material by adopting compressed gas;

S3, heating and melting the solid material crystallized in the step S2, preserving heat for 0-40 min, then cooling to 40+/-5 ℃, preserving heat for 10-40 min, and then blowing out the liquid material by adopting compressed gas;

And S4, heating and melting the solid material crystallized in the step S3, and discharging to obtain the 2,4, 6-tricresyl.

2. The method for recovering 2,4, 6-trimethylphenol from a2, 6-xylenol raffinate of claim 1, wherein the constituents of the 2, 6-xylenol raffinate consist essentially of 2, 6-xylenol, 2, 4-xylenol, 2, 3-xylenol, 2,4, 6-trimethylphenol, and 2,3, 6-trimethylphenol; wherein the mass content of the 2,4, 6-tricresyl is 60-75%, preferably 60-70%.

3. The method for recovering 2,4, 6-trimethylphenol from a2, 6-xylenol raffinate of claim 2, wherein the mass content of the 2, 6-xylenol in the 2, 6-xylenol raffinate is 0 to 1.5%;

and/or, the mass content of the 2, 4-xylenol is 0-30%;

And/or, the mass content of the 2, 3-xylenol is 0-5%;

and/or, the mass content of the 2,3, 6-tricresyl is 0-15%.

4. A process for recovering 2,4, 6-tricresyl from a2, 6-xylenol raffinate according to any of claims 1-3, characterized in that in step S1 the temperature of the 2, 6-xylenol raffinate before cooling is not less than 70 ℃, preferably not less than 75 ℃.

5. A process for recovering 2,4, 6-tricresyl from a 2, 6-xylenol raffinate according to any of claims 1-3, characterized in that in step S1, the temperature is reduced by introducing cooling water at 15±5 ℃, preferably 15±1 ℃;

In the step S2, cooling is carried out by introducing cooling water with the temperature of 30+/-5 ℃, and the temperature is preferably 30+/-1 ℃;

in step S3, the temperature is reduced by introducing cooling water at 40+ -5deg.C, preferably 40+ -1deg.C.

6. The process for recovering 2,4, 6-trimethylphenol from a2, 6-xylenol raffinate as claimed in any one of claims 1 to 5, wherein steps S1 to S4 are carried out in a melt crystallizer comprising a tube side, a shell side and a jacket, circulating cooling water is fed into the tube side and the jacket, and the shell side is fed into the 2, 6-xylenol raffinate.

7. The method for recovering 2,4, 6-tricresyl from a 2, 6-xylenol raffinate of any of claims 1-6, wherein the gauge pressure of the compressed gas is from 0.002 to 0.05Mpa;

And/or the compressed gas is one or more of compressed air, nitrogen and inert gas.

8. The method for recovering 2,4, 6-tricresyl from 2, 6-xylenol raffinate according to claim 1, comprising the steps of:

s1, adding 2, 6-xylenol raffinate above 70 ℃ into a crystallizer, introducing cooling water at 15+/-1 ℃ to keep the temperature of the 2, 6-xylenol raffinate at 15+/-1 ℃ for 20-35 min, and then blowing out liquid materials by adopting compressed gas until no materials flow out from a discharge port;

S2, introducing hot water with the temperature of more than 70 ℃, heating and melting the solid material crystallized in the step S1, preserving heat for 0-40 min, then introducing cooling water with the temperature of 30+/-1 ℃ to ensure that the molten material is preserved for 20-35 min at the temperature of 30+/-1 ℃, and then blowing out the liquid material by adopting compressed gas until no material flows out of a discharge hole;

S3, introducing hot water with the temperature of more than 70 ℃, heating and melting the solid material crystallized in the step S2, preserving heat for 0-40 min, then introducing cooling water with the temperature of 40+/-1 ℃ to ensure that the molten material is at the temperature of 40+/-1 ℃ for 10-40 min, and then blowing out the liquid material by adopting compressed gas until no material flows out of a discharge port;

s4, introducing hot water with the temperature of more than 70 ℃, and discharging after the heating value of the solid material crystallized in the step S3 is completely melted, so as to obtain 2,4, 6-tricresyl.

9. The method for recovering 2,4, 6-trimethylphenol from a2, 6-xylenol raffinate of any one of claims 1-8, wherein the liquid material collected in step S1 is 20-30% by mass of the 2, 6-xylenol raffinate, wherein the mass content of 2,4, 6-trimethylphenol is less than 42% by mass of the liquid material;

and/or the liquid material collected in the step S2 is 0-10% of the mass of the 2, 6-xylenol raffinate, wherein the mass content of the 2,4, 6-xylenol is below 35% of the liquid material;

And/or the liquid material collected in the step S3 is 0-10% of the mass of the 2, 6-xylenol raffinate, wherein the mass content of the 2,4, 6-xylenol is less than 45% of the liquid material.