Production method of 1-acetyl-2-pyrrolidone

Abstract

The invention discloses a production method of 1-acetyl-2-pyrrolidone. The method includes the steps of: taking 1, 3-propylene glycol, ammonia water, methyl acetate and methyl formate as the raw materials, carrying out amination, addition and cyclization reactions in a tubular fixed bed reactor under the action of a copper-based catalyst to obtain a 1-acetyl-2-pyrrolidone crude product, and further performing purification to obtain the 1-acetyl-2-pyrrolidone. The method provided by the invention has the characteristics of high catalyst catalytic activity, mild reaction conditions and simple technological operation, and the obtained product has yield of greater than or equal to 98.4%, selectivity of greater than or equal to 99.0%, purity of higher than or equal to 99.9%, a water content ofsmaller than or equal to 40ppm, and an ammonia content of less than or equal to 2ppm, thus meeting the requirements of downstream medicine, fine chemical intermediates and other fields.

Description

technical field [0001] The invention belongs to the field of production of fine chemical products, and in particular relates to a production method of 1-acetyl-2-pyrrolidone. Background technique [0002] 1-acetyl-2-pyrrolidone, molecular weight 127.4, density 1.15g / cm 3 , with a boiling point of 231°C, has a special smell, and has high biological activity. It can be used to synthesize acetylpyrrolidine, acetylpyrrole, etc. It is an important starting material in organic synthesis, so it is widely used in pharmaceutical chemical industry, fine chemical industry, Pesticide chemical, fragrance and cosmetic additive field. [0003] In the prior art, the catalysts used to synthesize pyrrolidone by amination of γ-butyrolactone are generally solid superacids, heteropolyacids or modified molecular sieves, such as: Zhang Zhide, etc. (refer to literature: Zhang Zhide, Lin Fengzhen, etc., 1-cyclohexyl- Synthesis of 2-pyrrolidone [J], Fine Chemical Industry, 2005, Volume 22, Issue 9)...

AI Technical Summary

Problems solved by technology

This method has the characteristics of short reaction time and high yield, but reducing the material at 240°C to 0-5°C in a short period of time requires high equipment requirements. At the same time, micro-reaction, as an emerging technology, has relatively high investment costs , the effect is not stable, also can find that its yield is the highest more than 90% from its embodiment, minimum only has 43.7%

[0005] The Chinese patent with the notification number CN105237456B discloses a production method of pyrrolidone products. It introduces the direct production of pyrrolidone by using 1,4-butanediol as a raw material through one-step reaction. , 4-butanediol is converted into pyrrolidone series products in one reaction unit through dehydrogenation-amination reaction. This method is completed in two reactors in one reaction unit. The first stage of reaction is 1,4 - Dehydrogenation of butanediol is mainly used to produce γ-butyrolactone, and the second-stage reaction is mainly based on the amination of γ-butyrolactone to synthesize pyrrolidones. The reaction temperature of the first-stage reactor is 190-260°C and the reaction pressure is 0.5- 8.0MPa, the reaction temperature of the second-stage reactor is 230-290°C, and the reaction pressure is 5-15.0MPa. Therefore, this patent is equipped with a buffer tank, a booster pump, Filters and heaters have complex structures and cumbersome operations, reducing the safety factor of workers during operations

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