An investigation on manufacturing of alumina microfiltration membranes

In this research, disk-type alumina microfiltration membranes with an approximate diameter of 21mm were synthesized via isostatic pressing method. Many samples were made and characterized based on the Taguchi experimental design to optimize the manufacturing procedure. The effect of alumina powder size, binder type and amount, sintering temperature, and pressing pressures was investigated. Porosity and water permeability of samples were measured, and SEM images were taken. The results showed that using different binders amounts can alter porosity from 25 to 49%, while type of binder has few effects on MF characteristics. Furthermore, water permeability of the samples varies from 170 to 3700 (kg/m(2).h.bar) depending on pressing pressure, alumina powder size, and sintering temperature. Using finer alumina powders and higher sintering temperatures can provide fewer porous and permeable membranes. SEM images confirmed formation of defect-free membranes. Confirmation of homogenized MF membrane approved by filtration of an industrial mineral oil. The results showed as follows: 100% rejection for particle size greater than 2 micron and more than 95% rejection for particle size bigger than 250nm.