Fabrication and Characterization of Low-Cost Tubular Ceramic Membrane for Microfiltration of Oily Wastewater

Abstract

The presence of notable quantities of oil in water is one of the prime causes of water pollution worldwide. The increased water pollution is creating nuisance to human and animal lives. To put an end to this threat, the treatment of oily wastewater is attracting everyone’s attention. The high efficacy of membrane filtration in separation operations makes researchers consider this technology for use in oily wastewater treatment. Hence, keeping this perspective in mind, tubular configuration membranes were fabricated using kaolin (30 wt %), quartz (30 wt %), calcium carbonate (28 wt %), boric acid (4 wt %) and feldspar (8 wt %). Membrane fabricated with this composition is found to possess a porosity value of 59.27 ± 1.002% and mechanical strength of 14.708 ± 2.603 MPa along with an average pore size of 0.092 μm. The surface of the membrane is smooth and free of any defects as observed under field emission scanning electron microscope. The membrane, due to its satisfactory physical and mechanical properties, is further used for the treatment of oily wastewater with three various concentrations and complete rejection of oil is achieved for all the concentrations. The successful separation of oil from the oily wastewater signifies size exclusion to be the dominant phenomenon for the rejection performance of the membrane. The droplet size distribution of the oil-in-water emulsion using laser particle size analyzer also reveals the same, with an average droplet size of oil lying between 2.884–3.802 μm for all three concentrations. The size of the droplets is far bigger than the average pore diameter of the membrane, which ultimately helps the membrane in retaining the oil content of wastewater. Therefore, looking at the outstanding oil removal efficiency of the membrane, it can be concluded that the membrane can be used industrially for the treatment of oily wastewater.