Development and Characterization of Alumina-Based Membranes for Water Purification

Abstract

High energy ball milling (HEBM) and pressure less sintering technique were performed to achieve a homogenous powder mixture and porous ceramic membranes of a-Al2O3/2%MWCNTs. A uniaxial powder compaction press was used to compress the powder mixture into circular green pellets (27 mm in diameter, 3-4 mm thickness) at three different pressure values of 100 MPa, 250 MPa and 400 MPa, followed by sintering at three different temperature values of 1200 °C, 1250 °C and 1300 °C under argon gas atmosphere. The effect of process parameters on the pore distribution and phase change was characterized by employing Field Emission Scanning Electron Microscopy (FESEM) and X-Ray Diffraction (XRD) respectively. Process parameters were found to have a strong influence on the characteristics of the developed membranes like diametrical strength, water permeability and porosity. Water flow rates varied from 950 l/m2.hr to 42 l/m2hr, porosity decreased from 48.57% to 28.87% and diametrical strength increased from 0.95 MPa to 11.06 MPa as compaction pressure was increased from 100 MPa to 400 MPa and sintering temperature was increased from 1200 °C to 1300 °C.