Jump to main content
Jump to site search

Issue 4, 2015
Previous Article Next Article

Chameleon behaviour of iodine in recovering noble-metals from WEEE: towards sustainability and “zero” waste

Author affiliations

Abstract

An effective and sustainable method for the selective leaching of metals from the non-ferrous metal fraction of Waste Electric and Electronic Equipment (WEEE) is described here. This method consists of a sequence of steps which involve the selective leaching of the different metals from the shredded sample by using environmentally friendly lixiviants in water. In particular: (1) a refluxing citric acid (3 M) solution which dissolves Sn, Zn, Pb, Ni, and other base metals; (2) NH3 in combination with an IO3/I mixture which allows one to oxidize Cu and Ag, and to separate them by selective AgI precipitation; (3) an I/I2 mixture (5.3 : 1 molar ratio) which is capable of leaching quantitatively Au metal from the solid residue. Each step is followed by a further treatment for: (i) high-rate metal and reagent recovery, in the case of NMs; (ii) inertization, in the case of heavy metals. The “chameleon” behaviour of iodine, which shows versatile redox/complexing/precipitating capabilities, allows one to achieve, on the one hand, a selective noble-metal (NM) leaching and, on the other hand, a simple and effective reagent and metal recovery. The comparison of the above described method with a similarly effective one previously patented by some of the same authors, allows one to point out that a significant improvement in sustainability is achieved in terms of lixiviant employment, which is of low cost, easily available and recyclable, and able to work in water solutions, while maintaining or improving its environmentally friendly character.

Graphical abstract: Chameleon behaviour of iodine in recovering noble-metals from WEEE: towards sustainability and “zero” waste

Back to tab navigation

Supplementary files

Publication details

The article was received on 15 Nov 2014, accepted on 12 Jan 2015 and first published on 12 Jan 2015


Article type: Paper
DOI: 10.1039/C4GC02237H
Author version
available:
Download author version (PDF)
Green Chem., 2015,17, 2208-2216
  • Open access: Creative Commons BY license
  •   Request permissions

    Chameleon behaviour of iodine in recovering noble-metals from WEEE: towards sustainability and “zero” waste

    A. Serpe, A. Rigoldi, C. Marras, F. Artizzu, M. Laura Mercuri and P. Deplano, Green Chem., 2015, 17, 2208
    DOI: 10.1039/C4GC02237H

    This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Material from this article can be used in other publications provided that the correct acknowledgement is given with the reproduced material.

    Reproduced material should be attributed as follows:

    • For reproduction of material from NJC:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the Centre National de la Recherche Scientifique (CNRS) and the RSC.
    • For reproduction of material from PCCP:
      [Original citation] - Published by the PCCP Owner Societies.
    • For reproduction of material from PPS:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the European Society for Photobiology, the European Photochemistry Association, and RSC.
    • For reproduction of material from all other RSC journals:
      [Original citation] - Published by The Royal Society of Chemistry.

    Information about reproducing material from RSC articles with different licences is available on our Permission Requests page.

Search articles by author

Spotlight

Advertisements