Metals such as gallium, indium and selenium are ‘hitchhiker metals’ which are not mined in their own right, but are by-products of mining for major industrial metals such as aluminium, copper and zinc.
Physicist and economist professor Robert Ayres, based at international business school INSEAD, said hitchhiker metals do not follow the same economic patterns as metals mined for their own sake, claiming that this means increased demand and rising prices will not necessarily resulting in greater output of these scarce materials.
Lasers, LED lighting and catalysts rely on hitchhiker metals and there are no known substitutes in a given application.
“While recycling of these rare metals would appear to present the most feasible option for stemming this potential disastrous metals shortage, there are a number of technical barriers to this process which urgently need to be addressed by researchers if the serious implications of this shortage are not to be felt in the near future,” said the Royal Society.
“There is only a finite quantity of each of these metals that will ever be available, yet – with minor exceptions – nobody is recycling today,” said Ayres. “Collection of these materials is difficult, and the chemistry is complicated, but the obstacles must be overcome and soon, or a number of important opportunities will be lost. More research is needed, and I suspect that new legislation as well as capital investment are going to be necessary.”
Professor Ayres spoke during a two day Royal Society discussion meeting titled ‘Material efficiency: providing material services with less material production’.
It explored some of the many challenges presented by a world in which material consumption is increasing but material production operates at virtually maximal energy efficiency.
“One third of the World’s energy is used very efficiently to make and shape materials and currently economic development is inextricably linked with increased material consumption,” said meeting organiser Dr Julian Allwood or the University of Cambridge. “However, in the near future, resource constraints coupled with the need to reduce greenhouse gas emissions are going to challenge this relationship between development and materials. In this meeting we explored ways of maintaining the services that materials provide – from packaging food to providing office space – while dramatically reducing the amount of material needed to deliver them.”