Zirconia Gels in Concentrated NaOH

The sol‐gel process was used to produce zirconia powders that were pressed into compacts. The powders were synthesized from zirconium n‐propoxide, diluted in propanol, and hydrolyzed with molar ratios of water either l‐to‐l or lo‐to‐l. Zirconia compacts produced in this manner were soaked in 1N NaOH to simulate a membrane cleaning process, and their weight loss was recorded. Zirconia samples with a higher weight fraction of tetragonal phase exhibited less weight loss than samples with more monoclinic phase. The weight fraction of the tetragonal phase was controlled by synthesis conditions and tiring temperature.