Tuesday, May 1, 2012
Napoleon Ballroom C-D, 3rd fl (Sheraton New Orleans)
Biodiesel has become more attractive recently because of its environmental benefits and the fact that it is made from renewable resources. Heterogeneous catalysts are promising for the transesterification and esterification reactions of vegetable oils to produce biodiesel. Unlike homogeneous, heterogeneous catalysts are environmentally benign and could be operated in continuous processes. Moreover they can be reused and regenerated. This study used as catalytic support chitosan, which is obtained from natural sources, product of chitin which is a major component of arthropod and crustacean shells. In addition, chitosan has many significant biological and chemical properties such as biodegradability, biocompatibility and bioactivity as well as polycationic properties. The chitosan was acidified with H2SO4 0.1 mol / L and used as catalyst in the esterification reaction of residual coconut oil with using ethanol. The effects of ethanol/fatty acid molar ratio (2:1 to 6:1), reaction temperature (25 to 45 °C) and catalyst concentration (2 to10% m/m) on the biodiesel production were determinate using complete factorial design 2³ with three central points. Statistical analysis indicated than ethanol/fatty acid molar ratio, had be found to bse the most significant variables affecting the conversion. The highest conversions (80.13% to 81.43%) were obtained at 25°C with 1% m/m catalyzed and higher molar ratio (6:1). In study of kinetic of synthesis, the the yield of biodiesel was higher in 3 hours and after remained constant. Chitosan maintained sustained activity even after being repeatedly used for 10 cycles and the biodiesel yield was not affected much in the repeated experiments.