Examining the evolution of metals utilized in printed circuit boards

• Published in: Environmental technology Vol. 38; no. 13-14; pp. 1696 - 1701
• Main Authors: Adie, Gilbert Umaye, Sun, Lingyu, Zeng, Xianlai, Zheng, Lixia, Osibanjo, Oladele, Li, Jinhui
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 18-07-2017; Taylor & Francis Ltd
• Subjects: Arsenic - analysis; Cathode Ray Tube; Cathode ray tubes; Circuit boards; composition; Copper; Design for recycling; e-waste; Electronic equipment; Electronic waste; Electronic Waste - analysis; Electronics industry; Evolution; Gold; Lead; Metal concentrations; Metals; Metals, Heavy - analysis; Printed circuit board; Printed circuit boards; Printed circuits; Product design; Silver; Sustainable design; Television; Tin; Waste management; e-waste; Printed circuit board; metals; cathode ray tube; composition
• ISSN: 0959-3330; 1479-487X
• DOI: 10.1080/09593330.2016.1237552

Management of waste electrical and electronic equipment (WEEE) has recently attracted worldwide attention because of high metal concentrations in them. Evolution of toxic and precious metals utilized in WEEE can not only reflect the adventure of eco-design, but can also guide the final recycling option. Pb, As, Cu, Au, Sn and Ag were determined in 10 composite samples of printed circuit boards of cathode ray tube televisions (TV-PCBs) that were produced between 1980 and 2005. The obtained results indicated that average metal concentrations in all TV-PCBs were - Cu: 10.6 ± 4.1%, Sn: 4.21 ± 0.90%, Pb: 3.15 ± 0.54%, Ag: 0.0215 ± 0.0068%, Au: 0.0068 ± 0.0049% and As: 0.0007 ± 0.0004%. No remarkable difference was found in compositions of Pb and Sn over the years, suggesting that there were no major modifications of Sn/Pb solder used in joining the circuitry system. The average composition of Cu fluctuated between 5.10% in 1980 and 12.8% in the mid-1990s and decreased afterwards. The decreases in Ag and Cu compositions could possibly be associated with thinner layers of these metals in newer model products.