离子液体体系中过氧化氢氧化油酸合成壬二酸

Ionic liquid-assisted oxidation of oleic acid to azelaic acid with hydrogen peroxide

以离子液体BMIMPF6为溶剂,采用钨酸为催化剂,50%的H2O2氧化油酸合成了高纯度壬二酸。通过考察催化剂用量、溶剂类型、环氧化产物碘值、离子液体循环使用次数、氧化裂解反应时间等因素对目标产物壬二酸收率及品质的影响,得出合成壬二酸的最佳条件为:60℃下,原料油酸、过氧化氢、钨酸、离子液体以1.0:3.0:0.04:1.24(摩尔比)混合反应1h后,用25%的过氧乙酸在90℃继续氧化裂解3h,可得产品壬二酸,收率为39%。产品通过FT-IR及GC-MS等手段进行了表征,纯度高达99%。环氧化产物与离子液体BMIMPF6易于分离,分离后的离子液体10次以内可以重复使用,其结构及性能基本保持不变。

Using tungustic acid as a catalyst and ionic liquid BMIMPF6 as the reaction media, high purified azelaic acid was synthesized by oxidizing oleic acid with 50% hydrogen peroxide. Factors such as dosage of catalyst, kind of solvents, iodine value of the epoxide, recycling degree of BMIMPF6 and reaction time of oxidative cleavage, affecting the yield of azelaic acid were studied. The optimum conditions were determined as follows ： the mixture of oleic acid was oxidized by hydrogen peroxide by stirring at 60℃ for 1 h with the molar ratio of n （ C18H34O2 ） ： n（ H2O2 ） ： n（ H2WO4 ）：n（ BMIMPF6 ） = 1.0： 3.0： 0.04： 1.24, the semi - finished product was further oxidized by 25% peracetic acid for 3 h at 90℃ . The product was confirmed by FT - IR and GC - MS analysis and it showed that the yield of azelaic acid was up to 39% with the purity about 99%. Ionic liquids were easily separated from the epoxide and could be reused 10 times, and their structure and characters were not changed ultimately.