Valorization of Printed Circuit Boards from Waste Electrical and Electronic Equipment by Pyrolysis

Abstract

Waste electrical and electronic equipment waste generated in the European Union (EU27) has been identified as one of the fastest growing waste streams in the EU, such that by 2020 annual arisings of waste electrical and electronic equipment will be 12.3 million tonnes. The EU have introduced the Waste Electrical and Electronic Equipment (WEEE) Directive which aims to promote the re-use, recycling and other forms of recovery of electrical and electronic waste. Printed circuit boards represent a particular category of WEEE that has attracted wide attention for treatment by pyrolysis technology. Printed circuit boards are composed of mainly a glass fibre reinforced polymer resin board onto which are manufactured components containing a wide variety of metals such as copper, iron, tin and lead. But also a range of very high value metals including gold, silver, and palladium. In this paper, the use of pyrolysis to treat waste printed circuit boards as a means to recover valuable materials, including the metals, an oil and gas product from the polymeric resin and glass fibre is reviewed.