Chelating ion-exchangers embedded in PTFE for decontamination of heavy-metal-laden sludges and soils

Selective removal of small amounts of heavy metal precipitates from the background of bulk amounts of innocuous sludge or soil is a challenging separation problem. This study identifies and investigates a novel material that has the potential to overcome such a challenge. The material, termed Composite Ion-Exchanger Material (CIM), is made of fine particles of chelating polymers entrapped in thin sheets of porous polytetrafluoroethylene (PTFE). The composite ion-exchange material is not fouled by high concentration of suspended solids but retains the original properties of the chelating exchangers. In this communication, various physico-chemical properties of the new ion-exchange material are discussed as regards their use in the decontamination of heavy-metal-laden soils and sludges.