Ceramic membranes and their use in separation processes.

Among the separation processes in the industry, those using membranes are usually considered as forming a new and promising field. From them, those which use ceramic membranes, which can be manufactured more selective now than some time ago, are especially relevant due to their high mechanic, thermal and chemical resistances. Here we will start by a summary description of the methods of synthesis of inorganic membranes and particularly ceramic ones. Traditional methods are presented as well as both the polymeric and the coloidal sol-gel techniques. In order to characterize them, pore size distributions and surface properties, including morphology, hydrophillicity and electrical properties should be investigated. Some techniques to study these structural and surface properties are summarily presented. The ceramic membranes can substitute polymeric ones in most of their typical applications with profit due to their better performances and durability.