Arash Khosravi

In this research the possibility of using cheap ceramic membranes for the treatment of oily wastewater and greywater was investigate. In this way, mono-layer, two layer, and three-layer hydrophilic ceramic membranes were fabricated by extrusion and cross-flow filtration. In mono-layer membranes, 5 types of ceramic membranes such as: Mullite, Mullite/Zeolite, Mullite/Zeolite/Activated carbon, Mullite/Silicon carbide, and Mullite/Silicon carbide/Active carbon were made and subjected to the sintering temperature at 1,150 °C (or 1,250 °C) in an electrical furnace. The XRD data of Mullite membranes showed that the quartz and mullite were the main phases of the membrane, while corundum and cristobalite (SiO2) phases were the minor ones. Furthermore, the XRD patterns of the composites membranes revealed that there was no undesirable phase transition either in Mullite or in silicon carbide by adding activated carbon. The results also showed that the incorporation of AC and natural zeolite in the structure of mono-layer ceramic membranes could enhance the porosity, PF and TOC (COD) rejection, which could be attributed to the hydrophilic nature of these materials and the increase in the micro and mesopore voids in the structure of the membranes. For example, by incorporation of natural zeolite and AC in the structure of Mullite membrane the oil removal efficiency increased from 78.5% to 98.5%, 76.1% to 98.2% and 73.2-97.4% for wastewater containing 500, 1,000 and 1,500 mg/L oil, respectively. To prepare a two-layer ceramic membrane, kaolin, α-alumina, and zeolite powders (50:30:20 wt. %) formed using the extruder technique as ceramic support membrane. The effects of sintering temperature (25 °C, 550 °C, 750 °C, 950 °C, and 1,150 °C) over the support membrane properties including porosity, shrinkage thermal as well as thermal and mechanical properties were measured through TGA, XRD and flexural stress analyses. Results indicated that the support membrane sintered at 550 °C, 750