Polymer-enhanced Ultrafiltration for Cu(II) removal from aqueous solutions: Comparison of PAA and PVA additives

Dangerous heavy metals should be eliminated from industrial effluents. Different methods are used for removing copper from aqueous solutions, including adsorption, membrane filtration, etc. Polymer-enhanced ultrafiltration is a method with low energy consumption, low cost, and feasibility for removing heavy metals. Polyacrylic acid and polyvinyl alcohol polymers in this method were used as additives to solutions to make contaminants larger; thus, they could be removed by the UF membrane with a molecular weight cutoff of 5 kilodaltons. Effects of parameters, such as pH, copper concentration, the weight ratio of polymer to copper, ionic strength of the influent solution, and filtration pressure on the performance of PEUF were examined. Response surface analyses were applied to see the simultaneous effect of the two parameters. The study showed that more than 90% copper removal was achieved at a pH range of 7 to 8 and a P/M ratio of 1 for both polymers, which shows the effectiveness of PEUF as a straightforward method.