Activity of heterogeneous catalysts in the methyl and ethyl transesterification of soybean oil.

The aim of this study was to evaluate the synthesis of methyl and ethyl esters of soybean using two different types of heterogeneous catalysts: mesoporous molecular sieve [CTA+]Si-MCM-41 and KF-clay. Reaction conditions using methanol were temperature of 80°C with molar ratio of 1:12 to oil/alcohol, and 1:9 to [CTA+]Si-MCM-41 and KF-clay, respectively. Reaction times ranged from 1 to 2 hours. With the application of ethanol, the catalyst mass was maintained and some conditions were changed, such as temperature at 100°C, molar ratio of 1:15 and 1:12, and reaction time of 4 hours. Catalysts were characterized by means of (BET) N 2 physisorption, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Conversions of ethyl esters were lower than those of methyl esters. With catalysts [CTA+]Si-MCM-41 and KF-clay, conversions of 6.4 and 63.3% by using ethanol as well as conversions of 91.0 and 95.2% with methanol were obtained.