E-waste: a fortune of future?
As heaps of obsolete and discarded electronic components are fast becoming a matter of concern in most third world countries, e-waste could be easily converted into a fortune using some microbes.
The discarded electronic products often contain several hazardous and toxic materials, including metals like lead, mercury and iron, which can be retrieved from the trash in pure form using 'bioleaching'.
"If the metals are extracted properly from the dumped products, this can surely create new business opportunities in recycling," Dr Sudhir Sayal of Jaypee University of Information Technology, told PTI.
'Bioleaching' is used widely in the mining industry to extract metals from their ores through the use of bacteria rather than adopting expensive traditional measures like roasting and smelting.
"There are certain microbes which can take out the metals from e-waste. Some species of bacteria and fungus can convert the scraps into a new source of metals," Sayal explained.
Microbes called Thiobacillus are able to leach out more than 90 per cent of available metals like copper, zinc, nickel and aluminium, while some species of Penicillium fungus can mobilise 65-95 per cent of metals available in the trash, said an article co-authored by three researchers, including Sayal, and published in "Current Science" journal recently.
"Depending on the micro-organisms used, metals might be recovered from solutions in 100 per cent purity," Dr Helmut Brandl of University of Zurich told PTI in an e-mail.
The focus of this process, however, is "primarily on the metal mobilisation and recovery of those and not on the detoxification of e-waste", Brandl said.
"India should have concrete plans to deal with the problem of e-waste accumulation in an environment-friendly way.
"To my knowledge, there is no 'bioleaching' process applied on industrial level for treatment of e-waste yet," Brandl added.