Process for the one-step preparation of lactide from liquid lactic acid
By using organic solvents containing nitrogen and sulfur and inert gas to remove water, the problems of low hydrolysis efficiency, large amount of polymerization reaction and catalyst deactivation in the one-step preparation of lactide from lactic acid have been solved, realizing efficient continuous production and high yield of lactide.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA PETROLEUM & CHEMICAL CORP
- Filing Date
- 2025-01-16
- Publication Date
- 2026-07-17
AI Technical Summary
In the existing one-step process for preparing lactide from lactic acid, the hydrolysis efficiency is low, the amount of polymerized product is large, the catalyst is easily deactivated, making it difficult to achieve continuous production. Furthermore, the temperature of the azeotropic solvent is difficult to control, affecting the reaction efficiency and catalyst life.
By mixing nitrogen- and sulfur-containing polar organic solvents such as dimethylpyrrolidone and sulfolane with lactic acid, combined with inert gas to carry away water, and by selecting appropriate reaction temperature and pressure, polymerization reactions can be avoided and catalyst activity can be maintained, thereby achieving high dispersion and continuous production of lactic acid.
It improves the conversion rate of lactic acid and the yield of lactide, extends the catalyst life, realizes the efficient and continuous production of lactide in one step, and reduces the amount of polylactic acid generated and the problem of catalyst carbon deposition and deactivation.
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Figure BDA0005245124940000061 
Figure BDA0005245124940000081
Abstract
Citation Information
Patent Citations
Method for generating lactide by one-step conversion
CN112574165A