Habib, Komal4; Schibye, Peter Klausen2; Vestbø, Andreas Peter3; Leinikka Dall, Ole4; Wenzel, Henrik4
1 Institute of Chemical Engineering, Biotechnology and Environmental Technology, Faculty of Engineering, SDU2 University of Southern Denmark3 Teknologisk Institut4 Institute of Chemical Engineering, Biotechnology and Environmental Technology, Faculty of Engineering, SDU
Neodymium-iron-boron (NdFeB) magnets have become highly desirable for modern hi-tech applications. These magnets, in general, contain two key Rare Earth Elements (REEs) i.e. neodymium (Nd) and dysprosium (Dy), which are responsible for the very high strength of these magnets allowing for considerable size and weight reduction in modern applications. This study aims to explore the current and future potential of secondary supply of neodymium and dysprosium from recycling of NdFeB magnets. For this purpose, Material Flow Analysis (MFA) has been carried out to perform the detailed mapping of stocks and flows of NdFeB magnets in Denmark. A novel element of this study is the value added to the traditionally practiced MFAs at national and/or global level by complementing them with a comprehensive sampling and elemental analysis of NdFeB magnets, taken out from a sample of 157 different products representing 18 various product types. The results show that the current amount of neodymium and dysprosium in NdFeB magnets present in the Danish waste stream is only 3 Mg and 0.2 Mg respectively. However, this number is estimated to increase to 175 Mg of neodymium and 11.4 Mg of dysprosium by 2035. Nevertheless, efficient recovery of these elements from a very diverse electronic waste stream remains a logistic and economic challenge.
Environmental Science and Technology, 2014, Vol 48, Issue 20, p. 12229-37
NdFeB magnets, Elemental Analysis, Material Flow Analysis, In-use stocks