Search

CN-122010681-A - Preparation method of methallyl alcohol

CN122010681ACN 122010681 ACN122010681 ACN 122010681ACN-122010681-A

Abstract

The invention discloses a preparation method of methallyl alcohol, which comprises the steps of adding tricarboxylic acid salt into a reaction kettle, adding water for dissolution, heating and refluxing, dropwise adding methallyl chloride, controlling the reaction temperature, cooling and filtering to obtain tricarboxylic acid ester solid, filtering for standby, adding sodium hydroxide aqueous solution into the tricarboxylic acid ester solid for refluxing and hydrolyzing, cooling and layering to obtain the methallyl alcohol and the tricarboxylic acid salt, and combining the tricarboxylic acid salt and the filtering after separation for recycling. The method has the advantages that the solubility of the polycarboxylic acid ester obtained after the esterification of the tricarboxylic acid salt is small in a solution, an esterification product is precipitated and can be naturally separated out, the esterification reaction can be carried out even under the condition of no catalyst, the reaction is simple and rapid, the polycarboxylic acid ester can be obtained through separation by simple filtration, the emulsification phenomenon of the carboxylic acid ester in a water layer is overcome, the corresponding alcohol and tricarboxylic acid salt are obtained through hydrolysis of the polycarboxylic acid ester, the methyl allyl alcohol is obtained through alcohol rectification, and the tricarboxylic acid salt can be recycled.

Inventors

  • Cai Zhangji
  • ZHOU BINBIN
  • ZHU XIANCHAO

Assignees

  • 宁波锦莱化工股份有限公司

Dates

Publication Date
20260512
Application Date
20241112

Claims (9)

  1. 1. A process for the preparation of methallyl alcohol, said process comprising: 1) Adding tricarboxylic acid salt which is sodium salt or potassium salt of trimellitic acid into a reaction kettle, adding water, dissolving, heating and refluxing; 2) Slowly dropwise adding halogenated hydrocarbon, and controlling the reaction temperature, wherein the halogenated hydrocarbon is methallyl chloride; 3) Cooling and filtering to obtain solid tricarboxylic acid ester, and reserving filtrate; 4) And directly adding the tricarboxylic acid ester solid into a sodium hydroxide aqueous solution, carrying out reflux hydrolysis at 100 ℃, cooling, layering to obtain the methallyl alcohol and the tricarboxylic acid salt, and combining the separated tricarboxylic acid salt with the filtrate for recycling.
  2. 2. The method for producing methallyl alcohol according to claim 1, wherein the esterification reaction of step 1) and step 2) is carried out without adding a catalyst.
  3. 3. The method for preparing methallyl alcohol according to claim 1, wherein the esterification reaction of step 1) and step 2) is carried out by adding a monovalent copper salt catalyst in an amount of 0.1 to 5% by mass of methallyl chloride.
  4. 4. A process for the preparation of methallyl alcohol according to any one of claims 1 to 3, wherein the esterification reaction in steps 1) and 2) is carried out at a reaction temperature of from 80 to 100 ℃.
  5. 5. The method for producing methallyl alcohol according to claim 4, wherein the reaction temperature of the esterification reaction is controlled by the dropping speed of a halogenated hydrocarbon, and the reaction temperature is not lower than 95 ℃.
  6. 6. A process for the preparation of methallyl alcohol according to any one of claims 1 to 3 wherein the molar ratio of halogenated hydrocarbon to tricarboxylic acid salt is from 1:0.3 to 2.
  7. 7. The process for preparing methallyl alcohol according to claim 6, wherein the molar ratio of halogenated hydrocarbon to tricarboxylic acid salt is 1:0.5-1.
  8. 8. A process for the preparation of methallyl alcohol according to any one of claims 1 to 3, wherein the sodium salt of a tricarboxylic acid is sodium trimesic acid, sodium trimellitate or sodium trimellitate.
  9. 9. A process for the preparation of methallyl alcohol according to any one of claims 1 to 3, wherein the solid tricarboxylic acid ester obtained in step 3) is based on di-and tri-esterification products.

Description

Preparation method of methallyl alcohol Technical Field The invention relates to the field of chemical synthesis, and relates to a preparation method of methallyl alcohol. Background Methallyl alcohol is an important organic compound, an unsaturated alcohol, and is mainly used as an organic synthesis intermediate for synthesizing perfumes, resins and the like. The preparation methods of methallyl alcohol are very numerous. One such method is direct hydrolysis of methallyl chloride using alkaline aqueous conditions, which is straightforward but produces a relatively high level of ether by-products, typically up to twenty percent, from the reaction of the hydrolyzed alcohol with the yet unhydrolyzed halocarbon. Another common hydrolysis method is to react methallyl chloride with carboxylate, typically cheaper acetate, formate and the like to obtain carboxylate, and then hydrolyzing the carboxylate under alkaline aqueous conditions, and the method is carried out in two steps, with the greatest advantage that ether by-products generated during direct hydrolysis of halogenated hydrocarbon can be avoided. However, the method has the disadvantages that (a) a relatively expensive monovalent copper catalyst is used for the reaction of the halohydrocarbon and the carboxylate, (b) the generated carboxylate is separated from an aqueous solution in a layering way in a reaction system, the carboxylate and a water layer are easily emulsified in the layering process, so that the separation is difficult and the separation time is long, and (c) the recovery and the reuse of the carboxylate are difficult to realize and the loss is relatively large. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a preparation method of methallyl alcohol, namely a reaction of halogenated hydrocarbon and tricarboxylic acid salt to prepare tricarboxylic acid ester, and then hydrolysis to prepare alcohol. The method comprises the steps of carrying out esterification reaction on methallyl chloride and tricarboxylic acid to obtain an organic ester compound, separating the organic ester compound in a precipitation manner, hydrolyzing the organic ester compound with sodium hydroxide solution to obtain alcohol and tricarboxylic acid salt, and recycling the tricarboxylic acid salt after obtaining an alcohol product. The method is characterized in that the solubility of the polycarboxylic acid ester obtained after esterification of the tricarboxylic acid salt in the solution is small, the esterification product obtained by the reaction is precipitated and can be naturally separated out and influenced by the rightward shift of the balance, the esterification reaction can be carried out even under the condition of no catalyst, the reaction is simple and rapid, and the polycarboxylic acid ester can be obtained by separating through simple filtration, so that the emulsification phenomenon of the carboxylic acid ester in a water layer is overcome. And then hydrolyzing the polycarboxylic acid ester to obtain corresponding alcohol and tricarboxylic acid salt, rectifying the alcohol to obtain a product, recycling the tricarboxylic acid salt, and obtaining the tricarboxylic acid salt with high recycling rate and low loss. The technical scheme of the invention is as follows: A process for the preparation of methallyl alcohol, the process comprising: 1) Adding tricarboxylic acid salt which is sodium salt or potassium salt of trimellitic acid into a reaction kettle, adding water, dissolving, heating and refluxing; 2) Slowly dropwise adding halogenated hydrocarbon, and controlling the reaction temperature, wherein the halogenated hydrocarbon is methallyl chloride; 3) Cooling and filtering to obtain solid tricarboxylic acid ester, and reserving filtrate; 4) And directly adding the tricarboxylic acid ester solid into a sodium hydroxide aqueous solution, carrying out reflux hydrolysis at 100 ℃, cooling, layering to obtain the methallyl alcohol and the tricarboxylic acid salt, and combining the separated tricarboxylic acid salt with the filtrate for recycling. Further, the esterification reaction of the step 1) and the step 2) is carried out without a catalyst. Furthermore, a monovalent copper salt catalyst is added in the esterification reaction of the step 1) and the step 2), and the catalyst dosage is 0.1-5% of the mass of the methallyl chloride. Further, the reaction temperature of the esterification reaction of the step 1) and the step 2) is 80-100 ℃. Further, the reaction temperature of the esterification reaction is controlled by the dropping speed of the halohydrocarbon, and the reaction temperature is not lower than 95 ℃. Further, the molar ratio of the halohydrocarbon to the tricarboxylic acid salt is 1:0.3-2. Further, the molar ratio of the halohydrocarbon to the tricarboxylic acid salt is 1:0.5-1. Further, the sodium salt of tricarboxylic acid is sodium trimesic acid, sodium trimellitate or sodium trimellitate. Further,