A study on the remediation of a real heavy metal-contaminated sediment was conducted using the four chelating agents ethylenediatninetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), citric acid and the S,S-isomer of the ethylenediaminedisuccinic acid ([S,S]-EDDS). Different chelant washing experiments were carried out at a chelant/total metal content of 1 and 10 mol/mol for treatment durations from 0.5 to 48 h to study the extraction kinetics of trace metals and major cations. The objective was to evaluate the removal efficiency of conventional chelating agents as compared to innovative, biodegradable species. Among the target contaminants, Cd, Cu, Pb and Zn were found to be adequately removed by both EDTA and EDDS, while NTA and citric acid yielded unsatisfactory results in some cases. It was also found that As was a critical contaminant which would require an additional specific treatment step, since the residual concentrations after the washing treatment were still far above the regulatory limit values. (c) 2006 Elsevier B.V. All rights reserved.
A kinetic study of chelant-assisted remediation of contaminated dredged sediment / Polettini, Alessandra; Pomi, Raffaella; E., Rolle; D., Ceremigna; L., De Propris; M., Gabellini; A., Tornato. - In: JOURNAL OF HAZARDOUS MATERIALS. - ISSN 0304-3894. - 137:3(2006), pp. 1458-1465. [10.1016/j.jhazmat.2006.04.022]
A kinetic study of chelant-assisted remediation of contaminated dredged sediment
POLETTINI, Alessandra;POMI, Raffaella;
2006
Abstract
A study on the remediation of a real heavy metal-contaminated sediment was conducted using the four chelating agents ethylenediatninetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), citric acid and the S,S-isomer of the ethylenediaminedisuccinic acid ([S,S]-EDDS). Different chelant washing experiments were carried out at a chelant/total metal content of 1 and 10 mol/mol for treatment durations from 0.5 to 48 h to study the extraction kinetics of trace metals and major cations. The objective was to evaluate the removal efficiency of conventional chelating agents as compared to innovative, biodegradable species. Among the target contaminants, Cd, Cu, Pb and Zn were found to be adequately removed by both EDTA and EDDS, while NTA and citric acid yielded unsatisfactory results in some cases. It was also found that As was a critical contaminant which would require an additional specific treatment step, since the residual concentrations after the washing treatment were still far above the regulatory limit values. (c) 2006 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
