Method for preparing alpha-acetyl-gamma-butyrolactone

Abstract

The invention relates to a preparation method for Alpha-acetyl-Gamma-butyrolactone. Ethyl acetate and Gamma-butyrolactone are used as the initial material, and the preparation method comprises a reaction section, a neutralization section and a distillation section. The reaction section comprises the following steps: firstly, a metallic sodium catalyst is added into a toluene solvent in nitrogen atmosphere, then the temperature is raised to 100 to 110 DEG C, and is maintained for 15 to 30 minutes; secondly, the mixed liquor of the ethyl acetate and the Gamma-butyrolactone is titrated into the toluene solvent after being treated in step one, heat preservation and reaction are performed for 2.5 to 3 hours at 85 to 90 DEG C, wherein, the mass compounding ratio between the ethyl acetate and the Gamma-butyrolactone is 1.55 to 1.70: 1; in the neutralization section, sulfuric acid is adopted for neutralization. Through the preparation method, high-purity Alpha-acetyl-Gamma-butyrolactone can be obtained, in addition, the operation of the method is simple, the production cost is low, and the security is good.

Description

technical field [0001] The invention belongs to the field of chemical product synthesis, in particular to a preparation method of α-acetyl-γ-butyrolactone. Background technique [0002] At present, there are mainly two routes for the preparation of α-acetyl-γ-butyrolactone. One is the process using ethylene oxide as the starting material, and the other is the process using γ-butyrolactone as the starting material. craft. Since ethylene oxide is a first-class flammable and explosive chemical, using ethylene oxide as the reaction raw material has serious safety hazards in the reaction, and it is also difficult to obtain high-purity α-acetyl-γ -butyrolactone: γ-butyrolactone is used as the starting material, and generally γ-butyrolactone is used to directly react intermittently with metallic sodium in an enamelled glass reactor. Because the reaction is too intense, the heat dissipation of the reactor is slow and the temperature Difficult to control and other issues, frequent ...

AI Technical Summary

Problems solved by technology

Since ethylene oxide is a first-class flammable and explosive chemical, using ethylene oxide as the reaction raw material has serious safety hazards in the reaction, and it is also difficult to obtain high-purity α-acetyl-γ -butyrolactone: γ-butyrolactone is used as the starting material, and generally γ-butyrolactone is used to directly react intermittently with metallic sodium in an enamelled glass reactor. Because the reaction is too intense, the heat dissipation of the reactor is slow and the temperature Difficult to control and other issues, frequent material punching, burning and explosion incidents in the production process have caused many domestic and foreign companies to stop using this process to produce this product

[0003] In Chinese patent ZL03128773.5, a preparation method of α-acetyl-γ-butyrolactone is disclosed. The method includes a reaction section, a neutralization section and a distillation section. The reaction section is to add a catalyst in a benzene solvent, After heating and stirring, cool down quickly, and then add dropwise the mixed solution of γ-butyrolactone and ethyl acetate to react at a temperature of 65-92 degrees Celsius. The catalyst is an alkali metal or a compound containing an alkali metal. Phosphoric acid is used in the neutralization section neutralization, but the purity and yield of α-acetyl-γ-butyrolactone produced by this preparation method are low