Abstract: Al-pillared montmorillonite prepared with Keggin cation and the calcined products at different
temperature were studied by means of XRD, specific surface area analyses and pore size distribution. The results showed that, when calcined
from 300 to 650℃, the d value of pillared-montmorillonite changed from 2.13nm to 1.74nm, and the specific surface area was
increased to 231.6m²/g. The microporosity of pillared montmorillonite changed because of calcination, with the increase of
temperature, the specific surface area was reduced, average pore size was increased, and volume of micropores decreased. Calcination destroyed the
micro-structure of Al pillared montmorillonite.

Key words: pillared montmorillonite, Keggin cation, specific surface areas, microporosity