Application of fractional factorial design to ZSM-5 synthesis using ethanol as template

A 2(IV)(4-1) fractional factorial design of experiments was applied to synthesis of ZSM-5 zeolite using ethanol as template. With only 16 experiments, two runs for each of the eight experiments, the following results were obtained in this study. Analysis of variance showed that the most important main effect was SiO2/Al2O3 molar ratio, and the most important two-way interaction variable was the interaction of H2O/SiO2 and SiO2/Al2O3 molar ratio. A mathematical model for ZSM-5 synthesis was derived from the experimental data and validated by residual plot analysis. An optimum gel composition, H2O/SiO2 = 40, SiO2/Al2O3 = 60, OH-/SiO2 = 0.15 and C2H5OH/SiO2 = 1.5, was found from surface plots. (C) 2009 Elsevier Inc. All rights reserved.