Method for separating and purifying nonane diacid

Abstract

The invention discloses a separation purification method of azelaic acid, belonging to the separation purification technical field of organic compound, which comprises depressurizing and distilling the oxidation solution obtained by treating ozonation-oxidation decomposition on unsaturated fatty acid to remove solvent and pelargonic acid, transferring left oxidation solution to a film evaporator to be distilled to obtain crude azelaic acid, extracting and recrystallizing the crude azelaic acid to obtain azelaic acid crystal. In the recrystallization of azelaic acid, the low-carbon dibasic acid of C<4>-C<8> in azelaic acid is dissolved in cold water, to be discharged along with crystallization mother liquor, and the left azelaic acid in the recrystallization mother liquor is recovered by the film separator. The obtained azelaic acid is transferred to a rising film evaporator to be dried and dehydrated and the dehydrated azelaic acid is evaporated by film to obtain the azelaic acid. The whole process can confirm the yield of azelaic aicd and obtain high-quality azelaic acid, while the whole system is sealed and the process has better environmental compatibility.

Description

technical field

[0001] The invention relates to the technical field of separation and purification of organic compounds, in particular to a separation and purification method of azelaic acid. Background technique

[0002] Azelaic acid is an important fine chemical raw material, and its industrial application is very extensive. The industrial use of azelaic acid is mainly for the production of azelaic acid plasticizers, and secondly for the synthesis of fragrances, lubricating oils and polyamides. In addition, it can also be used for the manufacture of electrolytic capacitors, skin protection and skin protection. disease treatment. The high added value of azelaic acid depends on the following quality indicators: the content of azelaic acid in the product should meet the requirements of the application field, the content of ketoacids and monoacids in the product should be as low as possible, and the acid value should be 587-594mgKOH / g. At the same time, the product must hav...