Oxidation Of Methyl Erucate For Preparation Of Brassylic Acid

It is a type of important organic reactions that unsaturated fatty acids and their derivatives oxidative cleavage reaction, which dicarboxylates is prepared through. Unsaturated fatty acid methyl ester become stable chemical raw material source with the development of bio-diesel technology, it's chemical application will make bio-diesel industry chain expand, and bring about significant economic and social benefits. This paper investigated that brassylic acid is obtained by methyl erucate oxidation reaction, which has important application value and significant theoretical significance.In this paper, the dihydroxy reaction of the unsaturated fatty acid methyl ester is investigated, hydrogen peroxide is used as oxidant. The comparative study is done in the following three ways: (1) The dihydroxy reaction process in tert-butyl alcohol solvent, taking tungstic acid as catalyst. In this method, an inevitable question existed that, vicinal diol will be further oxidized with the conversion rate of unsaturated fatty acid methyl ester improved. (2) The dihydroxy reaction process directly on solvent-free conditions, taking tungstic acid as catalyst. The problem of this method is that, hydrogen peroxide decompose obviously, the product of vicinal diol's selectivity decrease with the conversion rate of unsaturated fatty acid methyl ester improved. (3) Epoxidation reaction of unsaturated fatty acid methyl ester process firstly in the presence of formic acid or acetic acid, vicinal diol coud get in further hydrolysis. The process of this method is relatively complicated, its advantage is vicinal diol's total selectivity reached 85%, when the conversion rate of unsaturated fatty acid methyl ester was 98%.In this paper, oxygen oxidation cleavage of vicinal diol is further studied, taking Co/W binary catalyst. Vicinal diol can be effectively translated into azelaic acid and the corresponding dicarboxylic acid monomethyl ester. The result indicated that, the residual double bond of vicinal diol occur allylic oxidation; on the other hand, the corresponding ether, ester of vicinal diol can not be oxidized cleavage. The brassylic acid made from oxidation of methyl erucate, its selectivity depends directly on vicinal diol's selectivity.The paper also studied the recovery of tert-butyl alcohol solvent, tert-butyl alcohol aqueous solution extractive distillation is explored, taking ionic liquid as the extractant applied in that. Regarding experiment tested, six ionic liquid's selectivity on the water-tert-butyl alcohol system is compared. The result indicated that, acid-based ionic liquids [emim][OAc] has a lower viscosity and melting point, good selectivity and large-scale applications.