versão On-line ISSN 2411-9717
versão impressa ISSN 0038-223X
J. S. Afr. Inst. Min. Metall. vol.109 no.12 Johannesburg Dez. 2009
The processing of eWaste. Part 1: The preparation and characterization of a metallic alloy derived from the smelting of printed circuit boards
D.R. Groot; J.A.N. van der Linde
Department of Materials Science and Metallurgical Engineering, University of Pretoria
A brief overview is given of the issues regarding the processing of waste electrical and electronic equipment (WEEE). The printed circuit board component of WEEE is an exceptionally complex feed to possible recycling processes.
Scrap printed circuit boards were selectively smelted at 1 200°C to produce a metallic alloy. Iron and aluminium were found not to be part of the alloy. The alloy was characterized by SEM-EDS, and three phases were identified: alpha and delta bronzes, and a leadrich phase. Calculations show that about 56 mass per cent of the alloy is the alpha phase, 35 per cent delta phase and 9 per cent lead phase.
A simplified approach using appropriate binary phase diagrams was used to derive a phase composition for the alloy. This was further backed by FactSage calculations, which showed that the simplified approach was appropriate for this alloy. The experimental findings and theory were found to agree well.
“Full text available only in PDF format”
1. COHEN, D. Earth audit. New Scientist, 26 May 2007, pp. 34-41. [ Links ]
2. GROOT, D.R. and PISTORIUS, C.P. Can we decrease the ecological footprint of base metal production by recycling? Journal of the Southern African Institute of Mining and Metallurgy, vol. 108, no. 3, 2007. pp. 161-169. [ Links ]
3. GOOSEY, M. and KELLNER, R. A Scoping Study. End-of-Life Printed Circuit Boards. http://www.intellectuk.org/content/view/775/84/#PCBs (Last accessed May 2007). 2002. [ Links ]
4. eWaste Guide. http://www.ewaste.ch/valuable_materials_in_e_waste (Last accessed May 2007). [ Links ]
5. SODHI, M.S. and REIMER, B. Models for recycling electronics end-of-life products. OR Spektrum, vol. 23, 2001. pp. 97-115. [ Links ]
6. BAKER, H. ASM Handbook. ASM International, Ohio, USA. vol. 3, 1992. pp. 173-182. [ Links ]
8. GROOT D.R. and VAN DER LINDE J.A.N. The processing of eWaste. Part 2. The electrochemical leaching behaviour of a metallic alloy derived from waste printed circuit boards. Journal of the Southern African Institute of Mining and Metallurgy, vol. 109, no. 12, 2009. pp. 701-708. [ Links ]