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Was prepared from sodium tungstate, phosphoric acid, H2O2, and cetyl pyridinium chloride the phosphotungstic acid quaternary ammonium salt phase transfer catalyst. The influence of the solvent and the preparation conditions of the catalyst preparation process, the catalyst can be found solvent ethyl acetate the highly associative precipitated catalyst separation step is simple. Dichloroethane as solvent effects of reaction temperature and reaction time, of H2O2 Add way, H2O2 concentration and dosage, amount of catalyst factors epoxidation of fatty acid methyl esters and H2O2 utilization impact. The results indicate that the end of the reaction and the catalyst after cooling precipitated catalyst recovery is more than 90%, repeated use the eight catalytic activity basically unchanged. FT-IR were used to characterize the catalysts and epoxidation product. Phosphotungstic acid quaternary ammonium salt phase transfer catalysts and H2O2 (30%, mass fraction) oxygen source, respectively, in the two solvents ethyl acetate and 1, 2 - dichloroethane investigated epoxy fatty acid methyl ester synthesis process, and a method of using orthogonal experiment of fatty acid methyl ester epoxidation reaction conditions were optimized and the draw corresponding to the preferred reaction conditions are as follows: ethyl acetate 15mL reaction time 1h, the amount of catalyst 0.1g, catalyst type 3:1:4 four join the 30wt% H2O21.57g, the reaction temperature is 65 ° C, raw iodine value 100 fatty acid methyl ester via epoxidation epoxy value up to 5.0g of fatty acid methyl esters, 5.13%; dichloroethane 20 mL, reaction time 2.5h, the amount of catalyst 0.3g, three times adding 30wt% H2O23.5g, reaction temperature 65 ° C, fatty acid methyl ester 5.0g, raw iodine value of 100 fatty acid methyl esters by epoxidation, the product epoxy value of up to 5.78%. Formic acid as the active oxygen carrier, sulfuric acid as a catalyst and H2O2 as the oxygen source to study organic fatty acid methyl esters of the acid-catalyzed epoxidation. Effects of H2O2 dropping time the epoxidation reaction holding time, temperature, H2O2 amount of formic acid and sulfuric acid, the amount of impact factors on the reaction. The results show that the fatty acid methyl ester 40g (with C = C157.48mmol) reaction temperature of 55 ° C, 35% H2O218.36g (double bond molar ratio of 1.2:1), formic acid 6g, stirring speed the block 210r and · min-1, H2O2 drops plus time 0.5h, the reaction 3h, epoxy value of up to 4.27%, the corresponding H2O2 utilization was 69.27%; the highest epoxy value continue to react 2h, the the diol yield reached 88.05%, 95.17% 3h. Kinetic studies showed that the epoxidation reaction is a reaction, and the apparent activation energy is 45.97 kJ / mol.
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