Recycling Potential, Climate, and Metals of Modern Technology

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1336121 (Graedel). Many metals are scarce in nature, and concern exists regarding their long term availability. The prospective availability of metals over time is currently not aided by their rates of recycling after use, many of which are very low. Metals are also discussed from the perspective of carbon emissions: it is estimated that about 8% of all global carbon emissions relate to the mining and processing of metals. This research addresses these issues by deriving current loss and recycling rates for ten select metals, and evaluating the prospects for improving those rates now and over time. The work will also include computing the carbon emission savings that are now being derived from metal recycling, and the potential for increased carbon emission savings that could be achieved through increased after-use recycling. This research draws on previous NSF-sponsored research on the criticality" of all metals and metalloids in the periodic table. That research provides information on quantitative cycles of contemporary stocks, flows, and losses for these elements. The metal life cycles enable two new quantitative assessments to be made: the degree to which metal mined and processed in previous years is lost without further reuse, and the degree to which metal now lost could be recycled were appropriate effort expended in directed collection and reprocessing. In related work, scenarios are being developed for future supply and demand of metals. In this new research, the prior work will be used as a foundation for deriving a comprehensive picture of metal loss, recycling, recycling potential, and carbon emission reduction potential for ten metals: copper, nickel, cobalt, indium, neodymium, praseodymium, dysprosium, yttrium, europium, and terbium. The results will demonstrate the degree to which recycling can provide climate change-related benefits now and in the future, thus indicating the degree to which a more extensive deployment of technology and of product design for recycling has the potential to mitigate carbon emissions and thus climate change. The project includes an undergraduate research component involving two Yale students who will work part-time during the academic year and full time during the summers as members of the project research team. Their tasks will include a combination of independent and collaborative work involving current and best practice recycling of one or more target metals, together with collaborative work on resulting carbon emissions saving. A second category of broader impacts relates to providing information on materials recycling prospects and their potential for carbon emissions reduction to several governmental agencies in the U.S. and elsewhere that have asked to be kept appraised of this group?s research on topics related to metal futures. A third category of broader impacts relates to collaboration involving the results of the research in the integrated scenario activities of the UNEP International Resource Panel. Finally, it is anticipated that the results of this work will provide enhanced materials perspectives to a number of domestic and international corporations, those in the governmental materials policy arena, and those engaged in climate research or climate policy.