Recycling Solutions - Thanatia: The Destiny of the Earth's Mineral Resources - page 443

to 2010 world production 8 . If correct, this would lead to a considerable increase
in minor metal demand into the near term and a strong need to develop recovery
technologies from used devices at their EoL.
Unfortunately very few companies are affording such treatments. An exception
to this is the case of Umicore 9 . The following examples provided by Hagelüken and
Meskers (2009) describe some of the recovery processes of several residues:
Ceramic matrix of catalytic convertors: Pt, Pd and Rh are almost completely
and relatively easy to recover. The process does however result in the loss of
those rare earth elements used as washcoat.
Printed electronic circuit boards and mobile phones: here the process recovers
Au, Ag, Pd and Cu. It requires special conditions since the raw material con-
tains substances such as hazardous plastics. Nevertheless it essentially follows a
conventional metallurgy allowing high yield e ciencies even for the byproducts
Pb, Ni, Sn, Se, Te, Bi, In and Sb. However, neither REE nor Ta is recovered.
Rechargeable batteries from laptops, mobile phones or electric vehicles: here,
the technology to obtain Co, Ni and Cu is already well developed but its
economic viability depends on the price of the “paying metal”, currently cobalt.
As batteries are composed of a mix of metals, plastics and electrolytes, the
recovery process requires special safety procedures in order to avoid hazardous
emissions, especially in the case of Ni=Cd forms. Lithium and Mn can also be
recovered depending on their market price.
Thin-film photovoltaic modules with active layers deposited on a glass or plastic
support and composed of combinations of M = In;Ga in CuMSe 2 , or CdTe:
here a paying metal is missing or in such a low concentration that it hampers
economic recovery. Moreover when Cd is present, any thermal treatment causes
environmental concerns. Therefore its recycling is a real challenge, likely to
be only surpassed if prices and demand of In, Se and Te would reward such
investment.
Thus in many cases EoL technologies are still in their infancy. Each time a set
of paying metals is recovered it is done so at the expense of various others. This
is a consequence of the Second Law: whatever you do, the entropy of the Universe
will continue to grow. In layman's terms, the more one separates components of a
mixture, the more entropy is created, either at the expense of energy downgrades
or in the increase of entropy of the remaining unseparated mixture or both. This is
in effect what the authors refer to as the problem of “entropic backfire ” as seen in
the following section.
8 Te <450 t/a, In '600 t/a, and Se ' 2100 t/a, according to USGS (2012).
9 See http://www.umicore.com/en/ourBusinesses/recycling/. Accessed March, 2013