Thermal and Hydrothermal Stability of Al-Pillared Rectorites
Al-pillared rectorites (Al-REC) were synthesized from naturally occurring rectorite through exchange of interlamellar ions with hydroxyalumina polycations. Furthermore, Powder X-ray diffraction (XRD), Nitrogen adsorption-desorption isotherms, and Transmitting electronic microscopy (TEM) were applied in order to study the themal stability and hydrothermal stability of pillared materials. The Al-REC are thermally stable up to 800 °C. X-ray diffractograms of Al-REC calcined at 800 °C show a sharp and intense d001 peak, corresponding to a basal spacing of 2.75nm. In a 100% steam flow under atmospheric pressure at 800 °C for 20h, the characteristic d001 spacing of Al-REC decreases from 2.74 to 2.52nm, the sharp and intense d001 peak is still observed. And micropore area, mesopore volume and micropore volume retain 62, 33 and 67%, respectively, which affirms that this pillared clay has exceptional hydrothermal stability.
Jinsheng Liang and Lijuan Wang
H. Y. Xu et al., "Thermal and Hydrothermal Stability of Al-Pillared Rectorites", Advanced Materials Research, Vol. 178, pp. 314-317, 2011