Rapid Synthesis of Mesoporous Molecular Sieve SBA-15 by Different Techniques with Microwave Assistance

Abstract

Mesoporous molecular sieves SBA-15 were prepared by using two different procedures taken from the scientific literature. In the first procedure, a hydrogel was prepared with the molar composition: 1.0 TEOS: 0017 P123: 5.7 HCl: 193 H2O with stirring at 35 °C. In the second procedure a hydrogel was prepared with the molar composition: 1.0 TEOS: 0017 P123: 8.14 HCl: 168 H2O with stirring at room temperature. In both procedures the samples were synthesized in a microwave. The samples were characterized by X-ray diffraction (XRD), differential thermal analysis (DTA), nitrogen adsorption-desorption analysis, and scanning electron microscopy (SEM). The analysis of XRD and nitrogen adsorption-desorption showed that the samples prepared with stirring at 35°C presented a higher ordering degree, an increase of crystallinity and larger volume of adsorbed nitrogen. The differential thermal analysis reveals that the SBA-15 presented high thermal stability, and the SEM revealed fiber type morphology consistent with this type of material.