SIMULTANEOUS EXTRACTION OF ANIONIC AND CATIONIC METAL CONTAMINANTS AT SUPERFUND SITES

Soils and groundwater contaminated with heavy metals are serious environmentalproblems. More than 70% of 358 Superfund hazardous waste dump sites arecontaminated with zinc, while chromium, copper, and lead are found in more than50% of these sites. The environmental remediation processes used to clean upmetal contaminated sites generally produce large volumes of water contaminatedwith low concentrations of metals. the well established processes used toprecipitate metals and reduce them it non-hazardous solids are relativeinexpensive when carried out on concentrated wastewaters. However, these sameprocesses can be prohibitively expensive if applied to large volumes containingdilute metals as well as other pollutants. Thus, there is a need for a processthat inexpensively removes the metals from pump-and-treat or soil washing waterand concentrates them for ultimate reduction and disposal. Therefore, TDAResearch proposed to develop an emulsion liquid membrane process capable ofsimultaneously extracting heavy metal anions and cations from dilute, complexcontaminated streams and concentrating the metal species for subsequent treatmentand disposal.