Keywords: circular membrane, mixed clays, oily wastewater, oil–in–water emulsions, porosity, pore size, water permeability, stability, thermogravimetric analysis, TGA, SEM, wastewater treatment
Fabrication of circular shaped ceramic membrane using mixed clays by uniaxial compaction method for the treatment of oily wastewater
Circular shaped ceramic membrane was fabricated using inexpensive mixed clays by uniaxial compaction method and subsequently fired at 900°C. TGA analysis demonstrates that the minimum sintering temperature required to fabricate the membrane is above 800°C. A volume median diameter d(0.5) of the raw material mixture is found to be 2.78 µm. XRD analysis verifies that the membrane undergoes phase transformation during sintering. SEM images reveal that the membrane does not have any micro crack. The porosity, average pore diameter and pure water permeability of the membrane is found to be 34%, 0.464 µm and 7.82 × 10−7 m/s kPa, respectively. The flexural strength of the membrane is estimated to be 10 MPa that elucidates the good mechanical stability. The chemical stability of membrane is also found to be good. The performance of the membrane was evaluated by treating with synthetic oily wastewater. The rejection value is found to be varying from 60 to 96% and the maximum rejection of 96% with good permeates flux is observed for higher oil concentration of 200 mg/L at pressure of 69 kPa.