Preparation of Hafnia ceramic membranes for ultrafiltration

Stable sols of monoclinic hafnia have been prepared hydrothermally. The reaction conditions can be easily defined by controlling different parameters such as the temperature, the autoclaving time, the concentration of precursor in solution, the filling rate of the autoclave, and the pressure. Hafnia particles are characterized using several methods such as turbidity, granulometry, and microscopy. Particle charge, depending on the electrolyte concentration, is determined by electrophoresis measurements. The hafnia membranes, prepared from the sols, are characterized in static and dynamic conditions. The membrane properties are defined by pore diameters, cut offs, and water permeation.