High voltage pulses to recover copper from waste printed circuit boards

Abstract

Electronic waste (e-waste) is one of the rapidly growing solid waste streams around the world. Advancement in technology, increase in usage of electronic products and rise in population during the last decade is causing the rapid obsolescence of e-waste. E-waste generation is around 40 million tonnes each year and increasing at the rate of 3–5% per annum. E-waste is heterogeneous in nature and contains both valuable and hazardous materials. Printed circuit boards (PCBs), a key component is used in most of the electronics and contributes 3% by weight to the total e-waste. PCBs contain copper and gold 20 times more than their respective ores hence various physical, chemical, electrostatic, pyrolysis and metallurgical techniques are investigated to recover copper. But due to disadvantages such as (a) release of toxic gases during crushing (b) non-selective fragmentation between metals and non-metals (c) use of chemicals or acids (d) high energy utilization demands the environmental friendly and sustainable technique to recover copper from waste PCBs. In this study, we have used high voltage pulse technology to recover copper from waste PCBs. To achieve high recovery, operating conditions such as voltage and number of pulses were optimised. The results signify that applied electric voltage and number of high energy pulse were the important factors to segregate copper from waste PCBs. Reduction of noxious gases, high recovery of copper and negligible mechanical damage were the advantages of using high voltage pulse technology to recover copper from waste.