US: E-waste Recycling Breakthrough Offers 95% Metal Purity, 85% Yield

SEATTLE (Scrap Monster):  Researchers at Rice University have developed a groundbreaking method for recycling metals from electronic waste, or e-waste. Their novel method is targeted at enhancing the efficiency of metal recovery.

Besides, it promises to reduce the environmental impact traditionally associated with metal recycling processes.

“Metal recycling plays a crucial role in mitigating the shortage of critical metals and reducing reliance on primary mining,” said the researchers, led by Professor James Tour, in the study.

Conventional recycling methods, such as hydrometallurgy and pyrometallurgy, face several challenges.

“Current liquid hydrometallurgy involves substantial water and chemical consumption with troublesome secondary waste streams, while pyrometallurgy lacks selectivity and requires substantial energy input,” read the study.

However, the new method from Rice University avoids these issues. It allows for precise control of temperatures, thereby enabling the rapid separation of metals without needing water, acids, or other solvents.

“Our process offers significant reductions in operational costs and greenhouse gas emissions, making it a pivotal advancement in sustainable recycling,” said Tour.

Interestingly, this innovative technique is an extension of Tour’s earlier work with a process known as flash Joule heating (FJH).

FJH involves the rapid heating of materials to extremely high temperatures using an electric current.

This causes the materials to undergo transformations that allow for the extraction of valuable metals.

“The researchers applied FJH chlorination and carbochlorination processes to extract valuable metals, including gallium, indium and tantalum, from e-waste,” stated the researchers in a press release.

 The research team demonstrated the efficacy of their approach by extracting tantalum from capacitors, gallium from discarded light-emitting diodes (LEDs), and indium from used solar conductive films.

By precisely controlling the reaction conditions, the team was able to achieve a metal purity exceeding 95% and a yield surpassing 85%.

This new technique has major implications for metal recycling. The implications of this breakthrough are far-reaching. It has the potential to alleviate the pressing issue of critical metal shortages, which are hindering technological advancements and sustainable development.

Additionally, the reduced environmental impact of this method aligns perfectly with global efforts to combat climate change and promote a circular economy.

“This breakthrough addresses the pressing issue of critical metal shortages and negative environmental impacts while economically incentivizing recycling industries on a global scale with a more efficient recovery process,” highlighted Shichen Xu, a co-first author of the study.

Courtesy: www.interestingengineering.com