Preparation of Porous Cordierite with Thermally Stable Pore Structure

A cordierite ceramic with a thermally stable pore structure was prepared by a simple modification of a sol-gel reaction of alkoxide precursors, synthesized from Mg metal or Mg acetate, Al(i-OPr)₃, and partially prehydrolyzed Si(OEt)₄. For aging and drying, wet cordierite gel was treated with water vapor at 150°C to strengthen the gel network through enhanced hydrolysis and condensation reactions. The cordierite xerogels showed BET surface areas between 220–410 m²/g, depending on the catalyst and treatment conditions used. In particular, water vapor treated xerogel displayed comparatively thermally stable pore characteristics, which exhibited only a 4–17% decrease in BET surface area up to 700°C, while samples prepared using the conventional sol-gel method showed a 55–91% reduction. Both the DTA and XRD patterns showed that crystallization began at 900°C leading to the -Cordierite phase and the subsequent phase transition to -cordierite at temperatures between 1050 to 1250°C.