Gold Bio-Recovery for E-Waste

Unique ID

TO59549

Technology Status

Available

Technology Readiness Level

TRL5

Published on

19th Aug 2017

Updated on

17th Jan 2019

Technology Overview

The recall of the Galaxy Note 7, it has been estimated, will produce 157 million tonnes of precious metals used in the manufacture of the device. While this is an extreme example electronic waste is the fastest growing portion of municipal waste. As the amount of E-waste grows so does concern over the current treatment methods used such as chemical cyanidation and acid leaching. Instead of using energy intensive and toxic methods, the technology providerhas developed a more environmentally favorable solution: A modified bacteria that is able to leach gold in easily recoverable form. All you have to do is let these micro-organisms loose on E-waste containing gold and after a while the natural digestive process yields gold nanoparticles. This technology was developed tometabolically-engineered microbes to naturally produce cyanide to recover more gold from electronic waste. But this was only half the solution and subsequent development resultedin gold nanoparticles using engineered enzymatic systems from a common bacterium. This completely natural solution is neither energy intensive nor toxic and can yield almost half a kilogram of elemental gold from a tonne of E-Waste.

Technology Features & Specifications

Potential Applications

Current bioleaching processes using cyanogenic bacteria report a modest recovery of up to 11-15% of the total amount of gold present in solid waste. In contrast, the two engineered C. violaceum strains createdwere able to achieve gold recovery in excess of 30% of the total amount of gold present. The second technology helps to reduce the ions to elemental gold. Pilot-scale projects are being conducted with commercial partners to test the potential at the actual site of application. This innovation has the potential to replace methods for extracting gold from electronic waste in the market. Roughly 0.45 kilograms of gold can be extracted from every ton of electronic boards, and thus the electronic waste recycling industry has already become a rising industry with huge profits.

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