title: Adsorption of metal-ethylenediaminetetraacetic acid chelates onto lake sediment.
abstract: The adsorption of Ethylenediaminetetraacetic acid (EDTA) and its metal complexes, Cu, Fe(III), Hg, Mn and Ni, onto lake sediment was studied. The results reveal that EDTA and metal-EDTA complexes, even though being hydrophilic compounds, are indeed adsorbed within one months' contact time to some extent (6.3-24.8%). Less than 10% of Ni-EDTA, Cu-EDTA and EDTA salt was adsorbed, while the mass amount of Mn EDTA, Hg-EDTA and Fe(III)-EDTA found in sediment exceeded 15% after the contact period. Thus, adsorption of metal-EDTA chelates might be a relevant process in their removal from the aquatic environment. The metal-EDTA chelates in aqueous and solid phases were determined by gas chromatography-nitrogen phosphorus detection (GC-NPD) system. The complexes were extracted by phosphate solution prior to analysis. The ability of EDTA to desorb adsorbed heavy metals from sediments is also discussed.
authors.affiliation: Laboratory of Environmental Protection Technology, Helsinki University of Technology, Hut, Finland. mika.sillanpaa@oulu.fi
authors.forename: M
authors.initials: M
authors.lastname: Sillanpää
authors.forename: J
authors.initials: J
authors.lastname: Rämö
mesh_terms: D000327:Adsorption; D002614:Chelating Agents / Q000737:chemistry*; D004492:Edetic Acid / Q000737:chemistry*; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D019216:Metals, Heavy / Q000737:chemistry*; D014873:Water Pollutants / Q000032:analysis*
chemical_list: D002614:Chelating Agents; D019216:Metals, Heavy; D014873:Water Pollutants; D004492:Edetic Acid