Effect of Pollutant Species on the Performance of Chelating Membranes for Wastewater Treatment

Abstract A chelating membrane was fabricated to simultaneously remove metal ions and proteins from simulated wastewater. For a mixture consisting of a single ion and protein, the chelating membrane exhibited overall good separation performance (except for Cd2+), with both ion removal and protein rejection surpassing 90 %. The removal of metal ions highly depends on the chelation of amidoxime groups with ions rather than the complexation of proteins with ions. An increase in the content of metal ions has a detrimental impact on the protein rejection efficiency owing to the damaging effect of heavy metals on the protein. Similarly, increasing the amount of protein adversely affects the removal of ions due to the weakened chelation of amidoxime groups with metal ions.