Synthesis of ceramic microfiltration membranes for oil/water separation

Alumina and zirconia composite membranes without defects for oil/water separation have been produced by the reverse dip-drawing technique. The thickness (5-15 mu m) and the uniformity of the top layer could be appropriately controlled by adjusting process variables such as the slurry concentration and the flow rate of the slurry. The effective average pore sizes of alumina and zirconia top-layers are 0.16 mu m and less than 0.07 mu m, respectively. The composite membranes are found to be very effective for removing oil from o/w emulsions.