Process for preparing acetylacetone by conversion of isopropenyl acetate and special-purpose equipment thereof

Abstract

The invention discloses a process for preparing acetylacetone by transforming acetic acid propylene and comprises the following steps of: steaming the acetic acid propylene into gas by a vaporizer; then, putting the gas to a first-way carrier gas and / or using a self heat interchanger, then leading the gas come into a reformer to get reforming gas, and finally cooling down the reforming gas. The invention also discloses a special device for the process. In the process for preparing acetylacetone by transforming acetic acidpropylene, the flow quantity of carrier gas can be adjusted according to the different inventory ratings, thereby reaching to the optimal residence time, greatly reducing carbon deposition and prolonging carbon blowing period, realizing optimal conversion rate and selectivity, and having large work condition operation window. The self heat interchanger can save energy, realize precise temperature raising in section, and raising the selectivity and yield of the transformation reaction. The combination of using the first-way carrier gas and the self heat interchanger, which are cooperated to work, can raise reaction selectivity and yield, and increase the operation flexibility in the best working conditions.

Description

technical field [0001] The invention relates to a process for preparing acetylacetone, in particular to a process for preparing acetylacetone by conversion of isopropenyl acetate. Background technique [0002] Acetylacetone is an important chemical and pharmaceutical intermediate. Its synthesis route generally adopts the acetic acid-acetone process route, that is, firstly acetone absorbs ketene under the action of a catalyst to obtain isopropenyl acetate, and then 300-600 Under the condition of ℃, acetylacetone is converted into acetylacetone. Among them, the conversion rate and the selectivity of the conversion reaction to obtain acetylacetone by converting isopropenyl acetate directly determine the difficulty of subsequent separation and the unit consumption of the product. At present, there is no simple and effective way to improve the conversion rate and selectivity. Methods. [0003] U.S. Patent 2395800 proposes a method for changing the material of the reforming furn...

AI Technical Summary

Problems solved by technology

However, in addition to the added water reacting with acetic anhydride to generate acetic acid, the excess water will enter the recovered acetone during the recovery process of the conversion liquid. When this part of acetone is reused to absorb ketene, it will affect the activity of the catalyst and will combine with ethylene. The side reaction of ketone generates acetic acid. Therefore, the yield of the conversion process is increased by sacrificing the yield of the absorption process, which limits the application of this process.

Images