Impact of bentonite content on the structural, textural and mechanical properties of SBA-15 mesoporous silica beads

This work aims to evaluate the impact of bentonite content on the structural, textural and mechanical properties of SBA-15 beads prepared by shearing using an Eirich mixer. X-Ray Diffraction analysis (XRD) of conventional and sheared SBA-15 powders and bentonite-containing beads confirms the attainment of hexagonal structure. According to the nitrogen adsorption-desorption isotherms, the bentonite content has a significant impact on mesoporous volume. SBA-15 beads containing 9.1 wt% of bentonite (B-SBA-Be9), 16.7 wt% of bentonite (B-SBA-Be17) and 33.3 wt% of bentonite (B-SBA-Be33) showed an increase in mesoporous volume of 15, 25 and 20%, respectively. Indeed, the presence of the basic bentonite-water solution during the preparation stage of the beads generates a chemical attack of the SBA-15 walls that leads to the increase in the mesopores size. Beads containing 16.7 wt% of bentonite present more promising result in relation to their good balance between textural properties and mechanical strength. Thus, this sample could be used for a future application as a catalyst support for desulfurization process. Therefore, these results confirm that porosity and mechanical resistance are strongly dependent on the bentonite content and beads preparation process, in comparison to literature data.