title: Interaction of the water soluble fraction of MSW-composts with Pb(II) and Cu(II) ions.
abstract: In this study we report on the interactions between the water-soluble fraction (WSF) of two municipal solid waste composts (C1- and C2-WSF) with Pb(II) and Cu(II) ions at pH 4.5. The Me(II) addition to the compost-WSFs led to the formation of soluble Me(II)-organic complexes (as highlighted by FT-IR spectroscopy), and to a decrease of the trace metals' solubility, which was greater for Pb(II) than Cu(II). This was due to the formation of insoluble Me(II) complexes involving the water-soluble organic carbon (WSOC) and the inorganic anions within both WSFs [1.10 and 0.62 mmol L-1and 2.06 and 0.42 mmol L-1of Pb(II) and Cu(II) precipitated from C1- and C2-WSF respectively, when 6.4 mmol L-1Me(II) was added]. A loss of WSOC from both WSFs, i.e. ∼13% and <5%, was detected in the systems containing 6.4 mmol L-1Pb(II) and Cu(II) respectively. A significant contribution in the formation of Pb(II) precipitates was also due to phosphate, chloride and sulphate anions, since their concentrations in the WSF decreased of 80, 25 and 90%, respectively, after the addition of 6.4 mmol L-1Pb(II). A decrease of phosphate anions in both WSFs (∼30%) was found in the systems containing Cu(II).
authors.affiliation: Dipartimento di Agraria, Sezione di Scienze e Tecnologie Ambientali e Alimentari, University of Sassari, Viale Italia 39, 07100, Sassari, Italy. Electronic address: castaldi@uniss.it.
authors.forename: Paola
authors.initials: P
authors.lastname: Castaldi
authors.affiliation: Dipartimento di Agraria, Sezione di Scienze e Tecnologie Ambientali e Alimentari, University of Sassari, Viale Italia 39, 07100, Sassari, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Demurtas
authors.affiliation: Dipartimento di Agraria, Sezione di Scienze e Tecnologie Ambientali e Alimentari, University of Sassari, Viale Italia 39, 07100, Sassari, Italy.
authors.forename: Margherita
authors.initials: M
authors.lastname: Silvetti
authors.affiliation: Dipartimento di Agraria, Sezione di Scienze e Tecnologie Ambientali e Alimentari, University of Sassari, Viale Italia 39, 07100, Sassari, Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Deiana
authors.affiliation: Dipartimento di Agraria, Sezione di Scienze e Tecnologie Ambientali e Alimentari, University of Sassari, Viale Italia 39, 07100, Sassari, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Garau
mesh_terms: D007854:Lead; D019216:Metals, Heavy; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants; D017550:Spectroscopy, Fourier Transform Infrared; D014867:Water
chemical_list: D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants; D014867:Water; D007854:Lead
keywords: Compost water-soluble fraction; Pb(II) and Cu(II); Water-soluble inorganic anions; Water-soluble organic carbon