Process for separating tert-butyl acetate in medicine waste solvent through vacuum rectification by using super-gravity bed

Abstract

The invention relates to a vacuum rectification method using a super-gravity bed as core separating equipment, and discloses a process for separating and recycling a waste solvent in the synthetic process of statins or other medicines and recovering tert-butyl acetate in the solvent. During operation, the waste solvent enters from a place located between the two-layer and three-layer rotors of thesuper-gravity bed, wherein the rotating speed is 1000r/min, the reflux ratio is 4-10, the vacuum degree at the top of a tower is 20kPa-70kPa, and the temperature of a tower kettle is controlled at 70DEG C-85 DEG C, a tert-butyl acetate product with higher purity can be recovered in the tower kettle, the purity can reach 95% or more, the residual amount of isoprene is less than 1%, and the moisture content is less than 1000ppm, thereby fully meeting the requirements of recycling; and compared with traditional tower-type rectification operation, the process provided by the invention has the advantages of having a simple technological procedure, low energy consumption, a small occupied area of equipment, and high recovery rate of the product tert-butyl acetate, and being capable of effectively improving economic benefits.

Description

technical field [0001] The invention relates to the field of chemical waste solvent treatment, in particular to a vacuum rectification method with a high gravity bed as the core separation equipment, which separates and recovers tert-butyl acetate in waste solvents in the synthesis process of statins or other drugs, In particular, processes in which isoprene, the highest azeotrope, can be formed with tert-butyl acetate are removed. Background technique [0002] During the synthesis and production of drugs, a large amount of organic solvents are needed as solvents to dissolve macromolecular drugs or drug intermediates. Taking the production of statins as an example, a large amount of solvents such as isoprene, methyl tert-butyl ether, tetrahydrofuran and tert-butyl acetate need to be used in the synthesis process. Therefore, the pharmaceutical production industry is a large demand for solvents, but also a large producer of waste solvents. If the waste solvent is discharged ...

AI Technical Summary

Problems solved by technology

Shi Huahui et al. (Journal of Nanjing University of Technology, September 2010, Volume 32, No. 5, Page 24-27) published a rectification separation process for the purification of tert-butyl acetate, using two towers of deacidification tower and purification tower The process separates tert-butyl acetate, and the reflux ratio of the purification tower reaches 35, and the energy consumption is too high, which is obviously not suitable for the in-situ solvent recovery process of pharmaceutical companies

[0005] In view of the fact that tert-butyl acetate-isoprene can form the highest azeotrope, the general atmospheric distillation method not only cannot obtain the tert-butyl acetate solution of qualified purity, but also causes a large amount of loss of tert-butyl acetate, acetic acid The utilization rate and recovery rate of tert-butyl ester are greatly reduced

Images