Method for preparing azelaic acid by enzyme catalysis of hydrogen dioxide oxygenated oleic acid

Abstract

The present invention relates to a method of preparing for nonane diacid by an enzymatic catalysis oxidation system. The method is that oleic acid, lipase and solvent are stirred and mixed uniformly; hydrogen peroxide solution is dripped to react at the room temperature and to be filtered to recover catalyst; the solvent is recovered by rotary vaporization; ethyl acetate is used for recrystallizing to obtain 9, 10-dihydroxyl stearic acid; acetic acid peroxide solution is added into an oil phase of the 9, 10-dihydroxyl stearic acid to be extracted, filtered and dried to obtain the product of the nonane diacid. The highest yield of the nonane diacid can be 60 percent to 70 percent (counted according to the oleic acid). The method of the present invention has clean technology and friendly environment and does not pollute the environment; the first step of the epoxidation does not need heating, adding high-concentration hydrogen peroxide and noble metal catalyst and does not need being provided with oxygen and ozone for long time; no high pressure is required during the reaction; the lipase can be recycled for repeating use after the reaction; the implementing condition is simple, which is convenient for the large scale production.

Description

technical field [0001] The invention relates to a method for preparing azelaic acid through the oxidation of hydrogen peroxide catalyzed by lipase. Background technique [0002] Azelaic acid, also known as rhododendronic acid, is a white to yellowish monoclinic prism, needle-like crystal or powder. Molecular formula is C 9 h 16 o 4 , molecular weight 188.22, specific gravity 1.0291 (4°C), 1.225 (25°C), melting point 106.5°C, boiling point 286.5°C (13.33kPa), refractive index 1.4303 (111°C), easily soluble in hot water, hot benzene and alcohol, slightly soluble In water, ether and benzene. [0003] Azelaic acid is a medium-long-chain dibasic acid and an important intermediate in organic synthesis. With the development of science and technology, the application market of azelaic acid derivatives is getting wider and wider. According to statistics, the most important use of azelaic acid is to synthesize dioctyl azelate (DOZ) plasticizer, followed by ...

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Problems solved by technology

[0014] Some other hydrogen peroxide oxidized oleic acid reactions involve two-step reactions, but they are not strictly separated, such as: M.chael A et al. used tungstic acid as a catalyst to oxidize 60% hydrogen peroxide to obtain 9,10-dihydroxyl without Purify directly into the autoclave, and add 300 ml of distilled water dissolved with 1.2 g of cobalt acetate hydrate, pressurize to 70 atmospheres, react at a temperature of 66 ° C for 4.5 hours, cool to 50 ° C, and separate the water phase and the oil phase Separation, the water phase containing cobalt salt can be used for later experiments, the oil phase is extracted with distilled water at 90°C and crystallized to obtain azelaic acid, the organic phase is subjected to vacuum distillation to obtain nonanoic acid, and the remaining liquid is distilled under reduced pressure with sodium hydroxide The solution was saponified at 90°C. After acidification, azelaic acid and pelargonic acid could be further obtained, and the final yield was 75% of azelaic acid and 75.4% of pelargonic acid (Journal of Molocular Catalysis: Chemical, 1999, 150: 105-111)

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