Elaboration and Characterization of New Ceramic Ultrafiltration Membranes from Natural Clay: Application of Treatment of Textile Wastewater

A new filtration membrane was developed based on Tunisian natural clay. The choice of Tunisian clay as raw material in this work rests mainly on the related cost reduction and abundance characteristics, as the clay materials display noticeable ceramic pastes of a high plasticity and liable to exhibit an effective shaping ability. The raw material was milled and sieved at 250 µm, then mixed with water and organic additives to obtain a homogeneous paste. A ceramic porous tube was then prepared by extrusion and sintering at a temperature of 950 °C. Interesting properties of resistance to corrosion and extreme pH solutions as well as mechanical endurance were displayed. The deposition of a coating layer inside the tube was then achieved by means of “slip-casting” method, using 40 μm clay powder, water and polyvinyl alcohol solution (PVA). After thermal treatment at 800 °C, the membrane proved to be characterized with the water-permeability determination feature. The attained value of 256 L/h m² bar appears to reveal that the prepared membrane proves to belong to the Ultrafiltration domain. The relevant liability to be applied to the treatment of industrial textile wastewater turns out to display an interesting retention liability of pollutants, in terms of COD (Chemical Organic Demand), of 80% and turbidity of (>99%). A total color retention disposition was also achieved at a pressure above five bars.