5743
Chemistry and Nanotechnology
Environmental Sciences and Solar Energy

Extraction of Gold from Electronic Waste and Ores (No. T4-1910)

Lead Researcher: Prof. Igor Lubomirsky

Summary

A method for selective extraction of gold has been developed at the Weizmann Institute. This method allows the efficient and environmentally benign recovery of gold that is currently discarded of in large quantities from electronic waste from household appliances, consumer electronic devices and industrial equipment.
Prof. Igor Lubomirsky’s novel process is based on volatilization for selective extraction of gold using benign metal salts, rather than dangerous chlorine gas as a chlorinating agent or hazardous and polluting acid mixtures. The new process requires low temperatures and is free from hazardous waste, among its additional advantages over conventional methods.
We believe that this efficient technology is key to increased reclaimed gold, potentially resulting in the reduction of the demand for primary gold. 

Applications

·         No toxic input – chlorides are used rather than chlorine gas
·         No hazardous waste is generated in the process
·         Mild conditions. High-temperature furnaces and equipment are not required
·         Relatively simple setup in comparison to conventional ones
·         Small scale plants are economically viable
 

Advantages

Prof. Igor Lubomirsky and his group developed a novel method for the recovery of gold from spent household appliances, consumer electronic devices and industrial equipment, as well as from gold ores and sands.
The method comprises of crushing the spent material (such as PCB) to obtain a fine particulate material predetermined grain size and reacting it with chlorine containing salts rather than pure chlorine gas in a furnace at low temperatures (under 300oC). This is followed by cooling the volatile gold chloride product and converting it into solid phase metal.