Preparation method of ethyl acetoacetate

Abstract

The invention provides a preparation method of ethyl acetoacetate. The preparation method sequentially comprises the following steps of: (1) fully dissolving ethanol and a catalyst, then adding the mixture into an esterification reaction kettle, heating up, and dropwise adding ketene dimer; (2) after completing dropwise addition, insulating, and cooling to produce crude ethyl acetoacetate; (3) rectifying the crude product to obtain the finished ethyl acetoacetate. The preparation method is characterized in that the catalyst in the step (1) is an amine type ionic liquid catalyst which is selected from one or more of n-butylamine nitrate, n-butylamine acetate, ethylamine nitrate, ethylamine acetate, propylamine nitrate and propylamine acetate. According to the preparation method of ethyl acetoacetate, the amine type ionic liquid catalyst is researched and is good in stability, the stability of ethyl acetoacetate is enhanced under the action of the catalyst, the rectification yield of a product can be improved, the technological operations are simple, the raw material consumption is reduced, and the catalyst has obvious advantages and positive effects.

Description

technical field [0001] The invention belongs to the field of chemical production, and in particular relates to a preparation method of ethyl acetoacetate. Background technique [0002] Ethyl acetoacetate, English name: Ethyl acetoacetate, colorless to pale yellow clear liquid with pleasant fruity aroma, miscible with general organic solvents, melting point: -45°C (228K), boiling point: 180.8°C (454.0 K), relative density: 1.0282, specific gravity (21 / 4°C): 1.022-1.027, refractive index at 20°C: 1.418--1.421, flash point (closed cup) 84.4°C, viscosity: 1.5081mPa.s (25°C), Surface tension: 32.51mN / m (20°C), slightly soluble in water, 4.9% water-soluble in solvent at 25°C, 12% solvent-soluble in water, miscible with ethanol, propylene glycol and oil. Irritant and narcotic, flammable, there is a danger of burning when exposed to open flame, high heat or contact with oxidants. [0003] Function and use: As an industrial solvent, it is used in coatings, adhesives, ethyl cellulos...

AI Technical Summary

Problems solved by technology

[0008] The disadvantages of this process are: high requirements for rectification equipment, large equipment investment, low product content and low yield

[0010] The disadvantages of this production method are: the catalyst is difficult to remove, and filtration is difficult, which affects the quality of the product, resulting in a decrease in the purity of the product, thereby affecting the stability of the product

[0011] In summary, the disadvantages of the preparation method of ethyl acetoacetate in the prior art are that the equipment investment is large, the rectification requirement is high, the catalyst must be removed, the catalyst removal is not thorough, and the mother liquor purification still has catalyst residues, which affects the stability of the product. Low conversion rate, low rectification yield and low product content