Preparation of KF/Al_2O_3 solid base catalyst for transesterification of soybean oil to biodiesel

KF/Al2O3 solid base catalyst was prepared by impregnation method used for transesterification of soybean oil with methanol to biodiesel.Effects of catalyst preparation condition on the transesterification were investigated.Optimal condition for catalyst preparation was as follows: w(KF)=45%,impregnation time 6 h,calcination temperature 500 ℃.Conversion of 97.15% was obtained over the catalyst prepared under the optimal preparation condition under the following transesterification reaction condition: n(methanol)∶ n(oil)=12∶1,catalyst dosage 2.0%,reaction temperature(60-65) ℃,reaction time 3 h.The catalytic activation mechanism for KF/Al2O3 was discussed.