Title : Development of a low-cost TiO₂-doped ZrO₂/pozzolan-based ceramic nanofiltration membrane for efficient removal of dyes and heavy metal pollutants
Abstract:
In this investigation, we developed membranes with a structural composite layering designed to achieve heightened mechanical strength and minimal resistance to fluid flow. The tubular pozzolan support was created using the extrusion technique, and the sintering process at 950 °C resulted in a porosity of 40.5%, water permeability of 1520 L/h.m2.bar, and robust mechanical resistance of 20 MPa. This support served as the base for an intermediate layer, formed through the slip-casting process, involving nano-TiO2 and subsequent sintering at 750 °C, resulting in an average pore diameter of 12 ± 0.5 nm and water permeability of 260 L/h.m2.bar.The activated nanofiltration layer was successfully fabricated using a modified colloidal sol-gel process, employing a combination of Zr-inorganic salts and Ti-alkoxide. This was followed by slip casting and sintering at 550 °C. Characterization through XRD, SEM, and Nitrogen sorption confirmed the formation of the TDZ (TiO2-doped ZrO2) membrane. The resulting TDZ/TiO2/Pozzolan membrane demonstrated exceptional features, including an average pore diameter of 2.5 nm and water permeability of 20.5 L/h.m2.bar. This cost-effective nanofiltration membrane exhibited high efficiency in removing both dyes and heavy metals. The rejection rates for methyl orange and methylene blue were 94.2% and 99.36%, respectively. Additionally, the membrane demonstrated impressive rejection rates of 99.6%, 99.2%, and 99.4% for C (NO3)2, Pb(NO3)2, and Cr(NO3)3, respectively.
