Indian-Israel combo develops new tech to remove pollutants from wastewater

CHENNAI: Researchers from the Indian Institute of Technology Madras (IIT-M) and Tel Aviv University, Israel, have developed an aerogel adsorbent that can remove trace pollutants from wastewater.

"This graphene-modified silica aerogel removes over 76 per cent of trace pollutants (PPM level) in continuous flow conditions, offering a sustainable path for large-scale water purification. The research team is dedicated to enhancing these results for large-scale applications," said a release from IIT-Madras.

Elaborating on the need for such research, professor Rajnish Kumar of IIT-M, said, "Indigenous techniques for wastewater purification have become essential not only to combat pollution but also to preserve water quality, protect ecosystems, and mitigate health risks associated with contaminated water."

"Conventional wastewater treatment methods struggle to remove traces of pollutants, especially pharmaceuticals. In response, scientists have explored various methods, including adsorption, advanced oxidation processes, and membrane filtration. Among these, adsorption is attractive because of its eco-friendly nature, cost-effectiveness, and efficient pollutant removal capabilities," he detailed.

Speaking about the technical aspects of this research, Professor Hadas Mamane of Tel Aviv University, Israel, said, "This jointly developed GO-SA aerogel can be customised to target specific contaminants by modifying their surface chemistry, making them versatile. Furthermore, they can be regenerated and reused multiple times, reducing waste and operational costs, making them a sustainable solution for water purification."

The findings were recently published as a paper in the prestigious journal Nature Scientific Reports (https://doi.org/10.1038/s41598-023-43613-w).

Aerogels, which are incredibly lightweight solids composed mostly of air, are excellent adsorbents (a solid substance used to remove contaminants).

In addition, they offer advantages like adjustable surface chemistry, low density, and a highly porous structure. These materials, often referred to as 'solid air' or 'frozen smoke', can be easily fabricated.

India, facing the challenge of supporting 18 per cent of the world's population with just 4 per cent of global water resources, has intensified efforts to address water pollution, particularly in water-intensive industries like pharmaceuticals and textiles.

The textile sector alone discharges nearly ten lakh tons of toxic synthetic dyes annually, posing severe threats to aquatic life and ecosystems.