IIT Madras & Tel Aviv University researchers develop aerogel adsorbent to remove pollutants

According to IIT Madras, this graphene-modified silica aerogel removes over 76 per cent of trace pollutants (PPM level) in continuous flow conditions.

Researchers from IIT Madras and Israel's Tel Aviv University developed an aerogel adsorbent that can remove trace pollutants from wastewater.

The research team developed a silica aerogel modified with graphene. They employed a method called 'supercritical fluid deposition' to prepare these modified aerogels and studied their effectiveness.

According to a press release by IIT Madras, this graphene-modified silica aerogel removes over 76 per cent of trace pollutants (PPM level) in continuous flow conditions thus offering a sustainable path for large-scale water purification.

The research was led by Shanti Swarup Bhatnagar Prize Awardee Prof Rajnish Kumar from IIT Madras and included Subhash Kumar Sharma and P Ranjani, Research Scholars, Department of Chemical Engineering, IIT Madras and Prof Hadas Mamane, School of Mechanical Engineering, Tel Aviv University, Israel.

Aerogels also known as ‘solid air’ or ‘frozen smoke’ are excellent adsorbents (a solid substance used to remove contaminants) and are incredibly lightweight solids composed mostly of air. In addition, they offer advantages like adjustable surface chemistry, low density, and a highly porous structure. The findings were recently published as a paper in the prestigious journal Nature Scientific Reports, mentioned the press release.

“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,” said Prof Rajnish Kumar, Department of Chemical Engineering, IIT Madras.

“This jointly developed GO-SA aerogels can be customized 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,” said Prof Hadas Mamane, School of Mechanical Engineering, Tel Aviv University, Israel.

The research team developed a silica aerogel modified with graphene. They employed a method called 'supercritical fluid deposition' to prepare these modified aerogels and studied their effectiveness. The Graphene-doped modified silica aerogels (GO-SA) were found to exhibit efficiency in purifying water, attracting and removing contaminants due to graphene's unique molecular structure. Under real-life conditions mimicked in their experiments, the material removed over 85% of pollutants in controlled settings and more than 76% in continuous flow conditions, informed IIT Madras.