INORGANIC POROUS COMPOSITE SEMI-PERMEABLE FILM AND PROCESS FOR THE PREPARATION THEREOF

Porous inorganic composite semipermeable membrane provided with a support and a separating layer having pores whose mean diameter is smaller than 1 mu m and comprising at least two refractory metal oxides, characterised by the fact - that this separating layer consists of particles of a phase of a first oxide and of at least one second oxide which is dispersed and chemically bonded to the said phase of the first oxide, so as to constitute at least partially, on the one hand, the free surface of the said particles of the said phase and, on the other hand, their particle joints, - that the said first and the said second oxides are chosen so that the said second oxide slows down the diffusion at the free surface of the particles and at the joints of particles of the said phase of the first oxide and has a low solubility in the said phase at high temperature, - and that the volume of the said second oxide is between 9.1 % and 25 % of the volume of the said phase of the first oxide.