Issue 10, 2018

A novel thermodynamic approach for the complexation study of toxic metal cations by a landfill leachate

Abstract

Landfill leachates can contaminate nearby aquifers. The hazards deriving from this contamination also depend on the chemical speciation of various contaminants. A novel approach is proposed here to face this problem from a chemical thermodynamics point of view. The complexing ability of the soluble fraction of a landfill leachate (collected from Bellolampo, Palermo, Italy) towards Pb2+, Cd2+ and Cu2+ has been investigated at T = 298.15 K in NaClaq at I = 0.1 mol dm−3. The soluble fraction of the landfill leachate was first characterized by different analytical techniques. Then, its acid–base properties were studied by ISE-H+ potentiometric titrations and modelled by the so-called diprotic-like model. Differential Pulse Anodic Stripping Voltammetry (DP-ASV) titrations of metal ion aqueous solutions with a diluted landfill leachate were carried out, successively, in order to determine the stability constants of the leachate-metal complexes. The stability of the Pb2+/OH and Pb2+/Cl complexes was also studied by the same technique. Finally, the sequestering ability of the leachate towards the investigated metal cations has been quantified by the calculations of various pL0.5 values under different pH conditions. The results proved that the landfill leachate is a good sequestering agent toward those cations, reducing the fraction of the free cations in solution, and that it can be a selective sequestrant at different pH.

Graphical abstract: A novel thermodynamic approach for the complexation study of toxic metal cations by a landfill leachate

Supplementary files

Article information

Article type
Paper
Submitted
16 nóv. 2017
Accepted
25 jan. 2018
First published
25 jan. 2018

New J. Chem., 2018,42, 7640-7648

A novel thermodynamic approach for the complexation study of toxic metal cations by a landfill leachate

S. Cataldo, G. Lando, D. Milea, S. Orecchio, A. Pettignano and S. Sammartano, New J. Chem., 2018, 42, 7640 DOI: 10.1039/C7NJ04456A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements