Author(s)

T. Chen, P. Jiang, M. A. Harney, G. M. L. Lazarus, B. Chen, Y. Song, H. Chen, G. L. Serke, G. M. Rose, M. B. Korzenski

Abstract

With <2% of the mass in US landfills, electronic waste (e-waste) accounts for 70% of hazardous materials. Approximately 5% by weight of e-waste consists of valuable secondary resource stock-printed wiring boards (PWBs). Those PWBs with high metal value are sold to overseas smelters and those PWBs with low value are sent to Asia or Africa where the integrated circuits (ICs) are manually desoldered and the trace precious metals are collected either by open burning or from chemical leaching with toxic chemicals such as hot aqua-regia and cyanide, which lead to environmental pollution and human exposure to hazardous chemicals. This paper reports novel cradle-to-cradle PWBs recycling processes and enhanced process efficiencies based on green chemistry and green engineering methodologies for the complete recycling of PWBs. We will describe that one can recover metals and valuable components from end-of-life (EOL) PWBs using cost effective, sustainable, and scalable methods. This includes both chemical desoldering and precious metal reclaim on ATMI’s eVOLV^TM PWBs recycling line.

Keywords

WEEE, e-waste, EOL, PWBs, green chemistry, green engineering, desoldering, gold leaching, ICs, recycling, valuable metals