| Crude corn oil was epoxidized with peroxyformic acid prepared by in-situ reaction of formic acid and low concentration of hydrogen peroxide as oxidant, strong-acid cation exchange resin NKC-9 as catalyst and ethylene -diamine tetraacetic acid disodium salt (EDTA-Na2) as promoter. The effects of dosages of EDTA-Na2, hydrogen peroxide, NKC-9 and formic acid, reaction temperature and reaction time on the epoxidization were studied, and the optimal process parameters were determined as follows: the respective dosage of EDTA-Na2, NKC-9, hydrogen peroxide and formic acid 0.01%, 13%, 110% and 17%(based on the mass of crude corn oil), reaction time 6 h, reaction temperature 55℃. Under these conditions, the epoxy value, epoxy rate, unreaction rate and ring opening rate of epoxidized corn oil were 6.49%, 85.85%, 2.83% and 11.32%respectively; comparing with the traditional sulfuric acid catalytic process, the epoxy rate of epoxidized corn oil with NKC-9 as catalyst was higher and the ring opening rate lowered by 0.7 percentage points. |
