Biodiesel from Transesterification of Cotton Seed Oil by Solid Bases Catalysis

Methyl esters (biodiesel) were produced by transesterification of cottonseed oil with methanol in the presence of solid bases as heterogeneous catalyst. The solid base catalysts MgO, CaO and MgO-Al2 O3 were prepared respectively from the dissociation of basic magnesium hydroxide, calcium carbonate and hydrotalcite at elevated temperature. The experiments show that the CaO and MgO-Al2O3 have high catalytic activity for transesterification reaction, and the yield of methy1 esters reaches over 90% under the condition of 230°C, methanol/oil mole ratio of 12, and catalyst dosage(catalyst/oil) of 2% after reaction 3h. The CO2-TPD profiles show that the catalysts CaO and MgO-Al2O3 have high base strength and more amount of base site, which implicates those catalysts will have a higher catalytic activity.