Search

CN-122011307-A - Method for synthesizing phenolic resin from 2,4/2, 5-methyl ethyl phenol

CN122011307ACN 122011307 ACN122011307 ACN 122011307ACN-122011307-A

Abstract

The invention belongs to the technical field of organic synthesis and separation, and particularly relates to a method for synthesizing phenolic resin from 2,4/2, 5-methyl ethyl phenol. The invention provides a method for synthesizing phenolic resin from 2,4/2, 5-methyl ethyl phenol, which comprises the steps of adding 2,4/2, 5-methyl ethyl phenol, aldehydes and a catalyst into a reactor for carrying out reverse heat preservation reaction, sampling and analyzing, wherein the 2, 5-methyl ethyl phenol is less than or equal to 0.5 percent and is qualified, heating, decompressing and dehydrating, evaporating unreacted 2, 4-methyl ethyl phenol and water, dehydrating to 100-200 ℃ to obtain linear 2, 5-methyl ethyl phenolic resin, adding the catalyst into the distilled material, heating to react the reacted 2, 5-methyl ethyl phenol (when formaldehyde in the distilled material is insufficient), adding a small amount of formaldehyde, extracting by a water-insoluble solvent, layering, removing a water layer from a wastewater treatment workshop, and rectifying an oil layer to obtain 99 percent of 2, 4-methyl ethyl phenol or pesticide intermediate 4-ethyl-2-cresol.

Inventors

  • QIN LIYING
  • WANG JING
  • SUN HUIQING
  • YAN CHUNPING
  • ZHAO JIAWEI
  • ZHAO YUAN
  • MENG DECHANG
  • SHI ZHIJIE
  • HAN XUE
  • Kong Bihua
  • CHEN YIMING

Assignees

  • 煤炭科学技术研究院有限公司

Dates

Publication Date
20260512
Application Date
20260211

Claims (10)

  1. 1. A method for synthesizing phenolic resin by 2,4/2, 5-methyl ethyl phenol, which is characterized by comprising the following steps: (1) Adding a part of 2,4/2, 5-methyl ethyl phenol, a part of aldehydes and a first catalyst into a polymerization reactor, stirring, heating to 80-105 ℃ to react for 1-6 hours, dropwise adding residual 2,4/2, 5-methyl ethyl phenol and residual aldehydes at 80-105 ℃ to react for 1-4 hours, preserving heat for 1-6 hours after dropwise adding, sampling and analyzing, and judging that the content of 2, 5-methyl ethyl phenol is less than or equal to 5 percent; (2) Cooling to 60-80 ℃, starting vacuumizing and dehydrating, wherein the dehydrating temperature is 80-85 ℃, the dehydrating time is 2-5 hours, the final pressure is-0.075-0.08 Mpa, and meanwhile, observing the water level of the receiver, wherein the water level is constant within 20 min; (3) Gradually increasing the vacuum to-0.09 to-0.1 Mpa in 1-2 hours, further heating and dehydrating at the same time, when the temperature of the materials in the kettle reaches 100-230 ℃ and no liquid is distilled, preserving the heat for 0.5-1 hour, stopping dehydrating, discharging the vacuum by using nitrogen, discharging the materials while the materials are hot under the protection of the nitrogen, and cooling to obtain the 2, 5-resol.
  2. 2. The method for synthesizing a phenolic resin according to claim 1, wherein in the step (1), a first phenol component including at least one of m-cresol, m-ethylphenol, m-isopropylphenol/m-propylphenol mixture, 3, 5-xylenol, phenol or 3-ethyl-5-cresol is added to a polymerization reactor; And/or, in the step (1), the dosage of the first phenol component is 0.1-200 wt% of 2,4/2, 5-methyl ethyl phenol.
  3. 3. The method for synthesizing phenolic resin from 2,4/2, 5-methyl ethyl phenol according to claim 1, wherein in the step (1), the 2,4/2, 5-methyl ethyl phenol is obtained by rectifying crude phenol extracted from coal-burnt crude phenol, medium-low temperature coal gasification crude phenol or coal pyrolysis of phenol-containing coal tar; And/or in the step (1), the 2,4/2, 5-methylethylphenol comprises 60-100 wt% of2, 4/2, 5-methylethylphenol, 0-30 wt% of 3, 5-xylenol, 0-20 wt% of m-p-ethylphenol, 0-30 wt% of 3, 4-xylenol, 0-10 wt% of2, 3, 6-trimethylphenol, 0-20 wt% of2, 4, 6-trimethylphenol and 0-5 wt% of m-p-isopropylphenol, wherein the 2,4/2, 5-methylethylphenol is 4-ethyl-2-cresol, 2-ethyl-4-cresol, a mixture of 5-ethyl-2-cresol and 2-ethyl-5-cresol, or the 2,4/2, 5-methylethylphenol is a mixture of 4-ethyl-2-cresol and 5-ethyl-2-cresol, or the 2,4/2, 5-methylethylphenol is a mixture of 2-ethyl-4-cresol and 2-ethyl-5-cresol.
  4. 4. The method for synthesizing a phenolic resin from 2,4/2, 5-methylethylphenol according to claim 3, wherein in the step (1), the aldehyde comprises at least one of paraformaldehyde, formaldehyde and acetaldehyde, and the molar amount of the aldehyde is 1 to 2.5 times the sum of the molar amounts of phenol, m-cresol, 3, 5-xylenol, m-ethylphenol, m-isopropylphenol, m-propylphenol, 3-ethyl-5-cresol, 3, 4-xylenol and 2, 5-methylethylphenol; and/or, in the step (1), a part of the 2,4/2, 5-methyl ethyl phenol is 0-100 wt% of the total amount of the 2,4/2, 5-methyl ethyl phenol, and a part of the aldehydes is 0-100 wt% of the total amount of the aldehydes.
  5. 5. The method for synthesizing a phenolic resin from 2,4/2, 5-methylethyl phenol according to claim 1, wherein in the step (1), the first catalyst comprises at least one of oxalic acid, formic acid, phosphoric acid, hydrochloric acid, sulfamic acid, benzenesulfonic acid, ammonia water or organic base, and the amount of the first catalyst is 0.5-10wt% of the total amount of phenolic materials.
  6. 6. The method for synthesizing the phenolic resin from the 2,4/2, 5-methyl ethyl phenol according to claim 1, wherein in the step (1), the first catalyst comprises at least one of sodium hydroxide, potassium hydroxide, sodium carbonate or ammonia water, and the dosage of the first catalyst is 0.5-10wt% of the total phenolic material; The step (2) is to add glacial acetic acid or formic acid for neutralization until the pH value is 6-7, gradually opening vacuum to-0.07 to-0.1 MPa within 0.5-1 hour, starting dehydration, observing that the dehydration speed is slow or until the temperature is reduced to about 70-75 ℃, heating to continue dehydration treatment, controlling the final temperature of liquid at 70-90 ℃ until the water level is reduced to a required value, and sampling and analyzing the water content of the material to be less than or equal to 5%; And (3) adding ethylene glycol after the dehydration treatment is qualified, uniformly stirring, sampling and analyzing the moisture and the viscosity, stopping vacuumizing when the moisture is 2-5%, adding ethanol to adjust the viscosity to 10-30 Pa.s, cooling to 40-50 ℃ and discharging to obtain the liquid 2, 5-resol.
  7. 7. The method for synthesizing the phenolic resin according to claim 5 or 6, which is characterized by further comprising the step (4) of adding a second catalyst into the distilled material, heating to 80-105 ℃ for reaction for 1-3 hours, sampling and analyzing the 2, 5-methyl ethyl phenol to be less than or equal to 0.5%, then adding a water-insoluble solvent, stirring for 0.5-2 hours, standing for 0.5-1 hour, layering, heating a lower water layer to 95-105 ℃ for removing a small amount of solvent, cooling the water layer after solvent removal to 40-50 ℃ for treatment in a wastewater treatment section, and taking an upper oil layer as a solution of unreacted 2, 4-methyl ethyl phenol.
  8. 8. The method for synthesizing the phenolic resin from the 2,4/2, 5-methyl ethyl phenol according to claim 7, wherein the second catalyst is an acidic catalyst or an alkaline catalyst, the acidic catalyst comprises at least one of oxalic acid, formic acid, phosphoric acid or hydrochloric acid, the alkaline catalyst comprises at least one of sodium hydroxide, potassium hydroxide, sodium carbonate or ammonia water, and the dosage of the second catalyst is 0.01-0.5 wt% of the total weight of phenolic material raw materials.
  9. 9. The method for synthesizing the phenolic resin from the 2,4/2, 5-methyl ethyl phenol according to claim 7, wherein the water-insoluble solvent comprises at least one of aromatic hydrocarbons, chlorinated alkanes, ethers, ketones or esters, and the water-insoluble solvent is used in an amount which is 0.5-2 times the total mass of phenolic material raw materials.
  10. 10. The method for synthesizing the phenolic resin by using the 2,4/2, 5-methyl ethyl phenol according to claim 7, wherein the oil layer is added into a distillation kettle with 5-30 trays, the solvent is removed by normal pressure and reduced pressure distillation after heating, the materials in the distillation kettle are transferred into a high-efficiency rectifying kettle with the tray number of 50-250, 99 percent of 4-ethyl-2-cresol or 99 percent of 2, 4-methyl ethyl phenol or 2, 4-methyl ethyl phenol/2, 4, 6-trimethyl phenol is obtained by rectifying, and kettle residues and 2,4/2, 5-methyl ethyl phenol raw materials are put into a polymerization reactor together for the next phenolic resin synthesis reaction; The pressure of reduced pressure distillation is-0.03 to-0.07 MPa, the reflux ratio (1-5) is 1, the pressure of rectification is-0.07 to-0.1 MPa, and the reflux ratio (5-40) is 1.

Description

Method for synthesizing phenolic resin from 2,4/2, 5-methyl ethyl phenol Technical Field The invention belongs to the technical field of organic synthesis and separation, and particularly relates to a method for synthesizing phenolic resin from 2,4/2, 5-methyl ethyl phenol. Background Phenolic resin is a synthetic resin formed by polycondensation of phenol and formaldehyde under the action of a catalyst, and has wide application in the fields of refractory materials, friction materials, packaging materials and the like due to the excellent performances of high temperature resistance, chemical resistance, bonding strength and the like. However, the raw material phenol is expensive, so that the production cost is high. Therefore, how to use 2,4/2, 5-methylethyl phenol to prepare phenolic resins is of increasing interest to those skilled in the art. Disclosure of Invention The present invention aims to solve at least one of the technical problems in the related art to some extent. To this end, the examples of the present invention propose a method for synthesizing a phenolic resin from 2,4/2, 5-methylethylphenol. The method for synthesizing the phenolic resin by using the 2,4/2, 5-methyl ethyl phenol comprises the following steps: (1) Adding a part of 2,4/2, 5-methyl ethyl phenol, a part of aldehydes and a first catalyst into a polymerization reactor, stirring, heating to 80-105 ℃ to react for 1-6 hours, dropwise adding residual 2,4/2, 5-methyl ethyl phenol and residual aldehydes at 80-105 ℃ to react for 1-4 hours, preserving heat for 1-6 hours after dropwise adding, sampling and analyzing, and judging that the content of 2, 5-methyl ethyl phenol is less than or equal to 5 percent; (2) Cooling to 60-80 ℃, starting vacuumizing and dehydrating, wherein the dehydrating temperature is 80-85 ℃, the dehydrating time is 2-5 hours, the final pressure is-0.075-0.08 Mpa, and meanwhile, observing the water level of the receiver, wherein the water level is constant within 20 min; (3) Gradually increasing the vacuum to-0.09 to-0.1 Mpa in 1-2 hours, further heating and dehydrating at the same time, when the temperature of the materials in the kettle reaches 100-230 ℃ and no liquid is distilled, preserving the heat for 0.5-1 hour, stopping dehydrating, discharging the vacuum by using nitrogen, discharging the materials while the materials are hot under the protection of the nitrogen, and cooling to obtain the 2, 5-resol. The method for synthesizing the phenolic resin by using the 2,4/2, 5-methyl ethyl phenol provided by the embodiment of the invention has the advantages and technical effects that 1, the method provided by the embodiment of the invention utilizes the difference of the reactivity of the 2, 5-methyl ethyl phenol and formaldehyde, uses part of cheap 2,4/2, 5-methyl ethyl phenol to replace phenol to produce the linear 2, 5-methyl ethyl phenolic resin, simultaneously produces 99%2, 4-methyl ethyl phenol (sometimes can produce pesticide intermediate 4-ethyl-2-cresol), p-ethyl phenol and the like, 4-ethyl-2-cresol and p-ethyl phenol have a price obviously higher than that of 2,4/2, 5-methyl ethyl phenol, has better economic benefits, simultaneously expands the application range and market scale of the 2,4/2, 5-methyl ethyl phenol, uses 2,4/2, 5-methyl ethyl phenol to replace phenol to produce the linear 2, 5-methyl ethyl phenolic resin, can effectively solve the problems of producing the refined 2, 4/5-methyl ethyl phenol produced by coal, 10 tons, and can produce the coal gasification coal, and has a great contribution to the coal gasification industry, and the market of the coal gasification industry is a new coal gasification industry, and the coal gasification industry can be greatly reduced. In some embodiments, in step (1), a first phenol component comprising at least one of m-cresol, m-ethylphenol, m-isopropylphenol/m-propylphenol mixture, 3, 5-xylenol, phenol, or 3-ethyl-5-cresol is added to the polymerization reactor; And/or, in the step (1), the dosage of the first phenol component is 0.1-200 wt% of 2,4/2, 5-methyl ethyl phenol. In some embodiments, in the step (1), the 2,4/2, 5-methyl ethyl phenol is obtained by rectifying crude phenol extracted from coal-burnt crude phenol, medium-low temperature coal-gasified crude phenol or coal-pyrolyzed phenol-containing coal tar; And/or in the step (1), the 2,4/2, 5-methylethylphenol comprises 60-100 wt% of2, 4/2, 5-methylethylphenol, 0-30 wt% of 3, 5-xylenol, 0-20 wt% of m-p-ethylphenol, 0-30 wt% of 3, 4-xylenol, 0-10 wt% of2, 3, 6-trimethylphenol, 0-20 wt% of2, 4, 6-trimethylphenol and 0-5 wt% of m-p-isopropylphenol, wherein the 2,4/2, 5-methylethylphenol is 4-ethyl-2-cresol, 2-ethyl-4-cresol, a mixture of 5-ethyl-2-cresol and 2-ethyl-5-cresol, or the 2,4/2, 5-methylethylphenol is a mixture of 4-ethyl-2-cresol and 5-ethyl-2-cresol, or the 2,4/2, 5-methylethylphenol is a mixture of 2-ethyl-4-cresol and 2-ethyl-5-cresol. In some embodiments, in the step (1), the ald