Manufacturing of ceramic membranes based on natural apatite

The aim of our study was to manufacture low-cost membranes. In the first part of this work, the results indicated that the addition of natural apatite to alumina to synthesize low-cost membrane supports enabled us to slightly reduce the sintering temperature. The low mechanical strength and high sintering temperature appear to be due to differences in properties between the two materials. Thus, the combination of alpha-alumina with apatite, which is a low-firing temperature material, remains difficult without the addition of other agents as sintering aids. The second part of this work is devoted to the manufacture of less expensive ceramic membranes based on natural apatite. The study of different formulations between apatite, alumina and metakaolin has shown that supports prepared from an apatite-metakaolin mixture, and sintered at 950°C present a good compromise between mechanical strength and porosity. Mesoporous membranes obtained by depositing a layer of titanium oxide on the prepared supports showed high dye retention rates.