Recycling of gold from electronics: Cost-effective use through ‘Design for Recycling’

Abstract

With over 300 tonnes of gold used in electronics each year, end-of-life electronic equipment offers an important recycling potential for the secondary supply of gold. With gold concentrations reaching 300-350 g/t for mobile phone handsets and 200-250 g/t for computer circuit boards, this "urban mine" is significantly richer than what is available in primary ores. However, the "mineralogy" in scrap products is much different than in the conventional ores in a gold mine: Up to 60 different elements are closely interlinked in complex assemblies and sub-assemblies, and this requires specialised metallurgical processes with extensive offgas treatment to recover gold and a wide range of other metals cost effectively and in an environmentally sound way. Moreover, the logistics to "excavate" and "haul" the scrap products to the concentrator and further to the smelter are much more challenging than in the primary supply chain. Currently, only a small portion of old products is collected and directed into state-of-the art recycling chains. Significant improvements are needed here to fully utilise this secondary metal resource.

Large-Scale WEEE Recycling Integrated in an Ore-Based Cu-Extraction System

“…Smelting and refining in a process specially designed or adapted to extract copper and other metals from WEEE scrap into a blister copper or crude copper bullion that is further refined into pure copper and where other metals contained in WEEE are extracted to a varying degree. Examples from Europe include the operation of Metallo [3], the operation of the Lünen plant belonging to Aurubis [4], Umicore operations in Hoboken [5,6], and Montanwerke Brixlegg in Austria [7], all of which are totally directed towards recycling, but to what extent WEEE is part of the recycled materials is not given. Umicore has totally shifted the operations at the Hoboken plant towards recycling and in total about 350 ktonne of precious metal-bearing secondary materials of all types is used.…”

Extraction of Gold(III) Using Cyclopentyl Methyl Ether in Hydrochloric Acid Media

“…Currently over 300 tonnes of gold are used annually in electronic components such as ICs, contacts and bonding wires [19].…”

A systematic review of environmentally conscious product design

“…It can be seen from the table that DFR were always studied in predefined environments, so that the characteristics of the materials or industries can be involved to make the recycling meaningful and more aim-specific. Table 2 List of DFR in specific material or industry Materials/Industries Related approaches Alloy [79] Chance-constrained based model Gold [80] Recycling gold from scrap electronics Composites [81] Analyze information shares and exchanges Plastic [82] Plastic product design in sustainability Metal industry [83] Recycling and implications for emissions Ship industry [84] Engineering philosophy targeting sustainable development…”