Sulfated-Alumina-Catalyzed Triacetin Synthesis: An Optimization Study of Glycerol Esterification

The catalytic activity of sulfated gamma-Al2O3wasevaluated for glycerol esterification using response surface method-ology (RSM) with a central composite design (CCD), having asresponse variable triacetin (TAG) yield. Temperature, glycerol/acetic acid molar ratio, and catalyst load were chosen as variables.The analysis of variance (ANOVA) verified that, for the studiedrange, only the temperature, molar ratio, their interactions, andquadratic terms were significant statistically. Among the adoptedconditions for sulfated gamma-Al2O3, the best result attained was 100%glycerol conversion and 39.9% TAG yield at 106.8 degrees C, 1:8 molarratio, and 0.75 wt % catalysts. The optimization indicated amaximum yield of 43.6% at 106.8 degrees C, 1:11.4 molar ratio, and 0.53wt % SO42-/gamma-Al2O3. The kinetic study of the reaction rate suggeststhefirst-order dependence on glycerol concentration and activation energy of 59.91 kJ mol-