Abstract

In this work, the results of the synthesis and characterisation of ultrafiltration membranes made on polysulphone are exposed. The membranes were synthesised using the phase inversion technique, changing the polymer and additive concentrations and considering different wet thickness of the moulding, in order to establish the effect of those variables of manufacture on the permeoselective properties of the membranes. The characterisation of every membrane permeability was done with the mesurement of water and gases flows with regard to the pressure applied, whereas the selectivity determination took place by means of the splitting of polysaccharides aqueous solutions. An increase in the polymer concentration caused simultaneously a decrease in the permeability and an increasse in the molecular cut. An increase in the additive concentration represented an increasse in the permeability and a reduction in the molecular cut. Finally, the increase of wet thickness caused a reduction of the permeability and the molecular cut. The obtained results showed the feasibility to manufacture membranes with predefined permeoselective characteristics, from an appropriate selection of the indicated variables.