Sol–Gel Route to Synthesis of Microporous Ceramic Membranes: Thermal Stability of TiO 2 –ZrO 2 Mixed Oxides

In this paper concerning the synthesis of microporous ceramic membranes, we focus on the preparation and ther‐ mal stability of unsupported microporous TiO 2 ‐ZrO 2 , mixed‐oxide membranes. It has been observed that, by add‐ ing up to 20% ZrO 2 , into TiO 2 , or up to 10% TiO 2 , into ZrO 2 , these microporous membranes display improved thermal stability. They can be fired up to 500°C for 0.5 h without closing micropores. However, membranes containing almost equal percentages of each component have lost microporous features and have low surface areas and low porosities. A phase diagram of a two‐component TiO 2 ‐ ZrO 2 , mixed‐oxide membrane has been prepared based on DTA and X‐ray diffraction data in order to better under‐ stand the microstructure changes upon firing.