Preparation of polymeric membranes based on cellulose acetate and modified by adding different amounts of a pore generating agent, which was polyvinylpyrrolidone (PVP), is presented and potential application of the membranes obtained for the removal of iron and copper ions from liquid phase is examined. Addition of various amounts of PVP has an impact on the physical (porosity, equilibrium water content and permeability) and chemical (content of the surface oxygen group, pH) properties of the membranes obtained. Filtration of iron and cupper solution leads to significant changes in the total content of surface oxygen groups, however the acidic oxygen groups remain dominant. With the content of PVP increasing within a certain range, the membrane permeability is improved. The membranes obtained show higher efficiency in removal of Fe 3+ than Cu 2+ ions, but with increasing content of PVP the efficiency in iron ions removal decreases and the total filtration resistance decreases after filtration of iron ions solutions.

The polymer membranes containing 18 wt% of cellulose acetate and different amounts of polyvinylpyrrolidone (PVP) as a cross-linker agent were used in the process of iron and copper ions removal from liquid phase. Depending on the content of PVP (changed from 1 to 4 wt.%) the membrane surfaces were characterised by different hydrophilic character and showed the dominant presence of surface oxygen-containing groups of acidic character. Irrespectively of the concentrations of solvents from which the metal ions had to be removed, the membranes showed better ability to remove Fe 3+ ions than Cu 2+ ones, and the membrane resistances decreased with increasing content of PVP. After the fi ltrations of solutions with iron ions the fl ux recovery ratio took rather high values; this ratio increased with increasing PVP content in the membrane.

No abstract