Preparation and Characterization of Cordierite Powder via Tween-80 Modified Citrate Sol-Gel Method

摘要

In this paper, cordierite (2MgO·2Al_2O_3·5SiO_2) precursors are synthesized using TEOS and aluminum and magnesium nitrates as starting materials, citric acid as chelating agent and Tween-80 as dispersant. The effect of citric acid and Tween-80 on the formation mechanism of α-cordierite phase is investigated by using X-ray diffraction (XRD), while the effect of citric acid and Tween-80 on the particle morphology of α-cordierite is examined by using scanning electron microscopy (SEM) and field emission scanning electron microscopy (FESEM). The results show that citric acid used as chelating agent can reduce the formation temperature of α-cordierite to 1150°C by forming stable salt of citric acid with all the metal ion to avoid composition deviation from the sample components during solvent evaporation process and sub-micron cordierite particles without hard agglomeration can be obtained. Nano-sized α-cordierite can be obtained with the introduction of Tween-80 as dispersant by modifying the surfaces of the colloidal sol particles.