IIT Madras Recovers Metals From E-Waste Using Nature

Researchers at the Indian Institute of Technology Madras have developed an innovative, sustainable method for extracting valuable metals from electronic waste. This breakthrough process employs environmentally friendly deep eutectic solvents, which are biodegradable liquid mixtures derived from natural substances.

The team successfully created a green solvent using thymol, sourced from thyme, and capric acid. This solvent demonstrated an effective ability to dissolve copper metal, paving the way for its recovery.

Subsequently, trisodium citrate, a non-toxic chemical, was used for extraction. This method allows for the direct synthesis of copper nanoparticles, which have significant industrial and technological applications.

By adjusting the solution's pH, researchers could produce different copper forms, including copper oxide nanoparticles and pure copper metal. The technique was also applied successfully to recover iron from actual electronic waste samples like printed circuit boards and copper sheets.

According to Prof. S. Pushpavanam, this new method is non-toxic, water-efficient, and generates no hazardous waste, distinguishing it from conventional acid-based extraction techniques. Its versatility in recovering multiple metals and producing nanomaterials directly makes it a more sustainable option.

Prof. Ranjit Bauri highlighted that this green recovery process can significantly reduce pollution and the environmental damage caused by e-waste, while also decreasing the need for virgin metal mining. This advancement aligns with India's sustainability and net-zero commitments.

Sinu Kurian, a PhD scholar involved in the research, noted that laboratory-scale results have validated the method's potential. The next steps involve scaling up the process for industrial use, improving solvent recyclability, and exploring cost-effective alternatives to enhance economic viability.