Low-cost clay-based membranes for oily wastewater treatment

Low-cost clay-based membranes with an excellent flexural strength were successfully prepared by a simple pressing route using low cost starting materials, such as kaolin, bentonite, talc, sodium borate, and carbon black, and subsequent sintering at 1000 degrees C. Carbon black was added as a template. The effect of carbon black content on porosity, flexural strength, pore size distribution, pure water permeability, oil rejection rate, and flux of low-cost clay-based membranes was investigated. It was found that the porosity and pore size of membranes increased with increasing carbon black content, whereas the flexural strength decreased with an increase in carbon black content. The pure water permeability increased with an increase in porosity. The oil rejection rate decreased with increasing applied pressure and carbon black content. Typical porosity, flexural strength, oil rejection rate, and flux of clay-based membranes sintered at 1000 degrees C were 34%, 58 MPa, 96.7%, and 6.3 x 10(-5)m(3)/m(2)s at an applied pressure of 101 kPa, respectively. (C) 2014 The Ceramic Society of Japan. All rights reserved.