Preparation and characterization of new ceramic membranes for ultrafiltration

Low cost asymmetric membranes have been prepared from natural materials. The flat ceramic supports were elaborated from natural kaolino-illitic clay using olive pomace as a pore forming agent. The effect of sintering temperature and pore forming agent on the mechanical strength, porosity, pore size distribution and permeability were evaluated. It was observed that with the increase of sintering temperature, the mechanical strength and the median pore diameter increase while the porosity decreases. The effect of the use of olive pomace was noticeable; it improved the porosity and permeability of the elaborated supports. The optimal support was made with 40% by volume of olive pomace and sintered at 1000 degrees C. Top layer was performed by dipping in an acid activated clay suspension. The effect of the percentage of solid content in the dipping solution was evaluated. It was noted that with the increase of the concentration of the dipping solution, the gaz permeability was slightly affected while the water flux presented a considerable variation. The optimal obtained membrane had gaz permeability of about 13.2 cm(3) s(-1) cm(-2) bar(-1) at a pressure of 1.5 bar and water flux of 2219 L h(-1) m(-2) at a pressure of 1 bar.