Fabrication of Nano-sized Copper Powders in Liquid Media via High-Energy Electrical Explosion Method: Use of High Purity Copper Recovered from Waste Jelly-filled Cable as a Raw Material

Abstract

Copper-basedcommunication cables have been widely used worldwide in sound signal
transmission and (ultrahigh speed) internet communication services by the major
Korean domestic and international cable manufacturers.  With depreciation of the copper-based
communication cables they are being replaced with fiber optics communication
cables and the waste copper-based communication cables are accumulating in
Korea, totaling approximately 10000 tons in 2008 including more than 6500 tons
of jelly-filled cable waste¹⁾.  High purity copper comprises more than 70% by
weight of the waste jelly cable and the recyclable quantity of copper therefrom
is estimated to be 4000 tons per annum.  Copper nano-powders are highly regarded as
functional materials for optical,catalytic, electrical and electronic applications owing to
their excellent electrical and thermal conductivities²⁾.  In the present study, a novel process
for wire explosion in oleic acid has been studied for fabrication of nano-sized
copper powders without particle agglomeration, formation of oxides and carbides.