Sequestration of (CH3)Hg+ by amino‐polycarboxylic chelating agents

Risultato della ricerca: Articlepeer review

8 Citazioni (Scopus)

Abstract

The speciation of mono-methylmercury(II) cation (MeHg+) in the presence of Nitrilotriacetate (NTA), Ethylenediamine-N,N,N′,N′-tetraacetate (EDTA), diethylenetriamine-N,N,N′,N″,N″-pentaacetate (DTPA) and (S,S)- Ethylenediamine-N,N′-disuccinic acid (S,S-EDDS) was investigated at I=0.1 mol L−1 (NaCl) with the aim to assess a trend of sequestering capacity of the amino‐polycarboxylic (APCs) ligand class towards this cation in aqueous solution. The results obtained gave evidence for the formation of a mononuclear[MeHg(APC)] complex species, differently protonated MeHg(HiL) species (i=1 to 3, depending on the APC considered), a mixed hydroxo species [MeHg(APC)(OH)] and a binuclear [(MeHg)2(APC)] species in all thesystems investigated. The results obtained in this work show that the stability of MeHg–APC complex species is very similar for DTPA, EDTA and S,S-EDDS (e.g., logKMeHg(APC)=10.14, 10.03, 10.14 for DTPA, EDTA and S,SEDDS, respectively) whereas, as expected, MeHg–NTA complexes are less stable (logK(MeHg)(NTA)=9.04). The sequestering ability of APCs towards MeHg+ ion was studied by calculating the sequestering parameter pL0.5in the pH range (3 to 11) investigated, in NaCl medium and also by simulating the presence of a non interacting medium, at the same ionic strength of the experiments. On the basis of the quite high pL0.5 values itcan be asserted that APCs can be used as sequestering agents for the remediation of contaminated soils and water. Of particular interest, from the environmental point of view, is the very good sequestering capacityof the S,S,-EDDS which is, among the APCs considered, the highest biodegradable chelating agent.
Lingua originaleEnglish
pagine (da-a)46-52
Numero di pagine7
RivistaJournal of Molecular Liquids
Volume172
Stato di pubblicazionePublished - 2012

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Condensed Matter Physics
  • Spectroscopy
  • Physical and Theoretical Chemistry
  • Materials Chemistry

Fingerprint Entra nei temi di ricerca di 'Sequestration of (CH3)Hg+ by amino‐polycarboxylic chelating agents'. Insieme formano una fingerprint unica.

Cita questo