Comparison of levels of Gold in Waste Mobile Phone Printed Circuit Boards and Gold Plated Finger Integrated circuits Found in Computer Mother Boards(GFICMs)

Abstract

Demand for gold has been escalating with increasing usage of electronic equipment globally. Around 267.3 million tons of gold are being consumed annually for manufacturing mobile phones, laptops and other electronic equipments.However, only 15% is recuperated from these equipments, the remainder lies in the storage yards or landfills as waste. The waste comprise of glass, plastics, wires, batteries, PCBs and metal casing. The PCBs are composed of precious metals which creates immense purpose for recycling and recovery. Printed circuit boards from electronic gadgets that are currently being dumped in landfills or incinerated cause a serious environmental harm in form of toxic gases or leached hazardous compounds. PCBs and Gold plated finger integrated circuits found in computer motherboards (GFICMs) contain high amounts of precious metals. The extraction of these metals from PCBs and GFICMS is both profitable and environmentally worthwhile. Hence this study assessed the levels of gold in waste mobile phone printed circuit boards and gold plated finger integrated circuits found in computer motherboards. Gold was extracted from 6 composite samples made from 18 waste mobile phone PCB samples and 12 GFICMsusing aqua regia and analyzed using Agilent Technologies Flame Atomic Absorption spectrometer model240FSAA.The average concentration of gold was found to be 111.1±11g of Au/ton of PCBs and 83.3±11g of Au/ton of GFICMs. The percentage difference in gold concentrations between printed circuit boards and gold plated finger integrated circuits found in computer mother boards was found to be 28.6±44%. Therefore PCBs are more potential secondary sources of gold than gold plated finger integrated circuits found in computer motherboards (GFICMs). Key words: Gold, Electronic waste, E-waste recycling, Printed circuit boards, GFICMs.