New carbon-based materials can remove dangerous “eternal chemicals” from the water

A diverse group of synthetic chemicals, Perfluoroalkyl and polyfluoroalkyl substances (PFAs) are commonly used in numerous products, including semiconductors, fire-steamed foam, heat-resistant, and non-adhesive cooking utensils. PFAs have a prominent resistance to heat, oil, grease, and water due to strong chemical bonds between atoms. However, the main drawback of exceptional resistance is that PFA is very persistent in the environment and earns the nickname “Forever Chemicals.”

The use of PFA is prohibited by international practice due to its harmful effects on human health and the environment. Recent scientific reports show that soil and rivers are contaminated with PFA, but there is a lack of effective and sustainable technologies to remove PFA.

United Nations Sustainable Development Goal 6 – Carbon-based materials for removing PFA from sanitary water in water and sanitary equipment for all.

A research team led by Associate Professor Manabu Fujii of Science Tokyo’s Faculty of Civil Engineering and Environmental Engineering will integrate the resistance of new adsorbents that can develop a membrane distillation (MD) method that traps chemicals on its surface and purifies PFAS-contaminated water. I did. .

Their findings were presented as lectures invited at the 23rd International Symposium on Ecomaterial Processing and Design, held from January 13th to 16th, 2025.

Isobe shares insight into the novelty of the research and says, “By utilizing lignin, a by-product produced in the pulp and paper industry, and glucose, a common sugar molecule, as a source of carbon, Isobe has been able to use it. Our research group adopted sustainable materials: PFAS-removal technology. Furthermore, the MD method, which combines both distillation and membrane separation, provides an innovative strategy to remove PFA from water.

Researchers utilized the difference in boiling points between water and PFA to purify PFA-contaminated water using the MD method. Furthermore, the hydrophobic (lack of affinity for water), porous carbon-based separation membrane effectively rejected PFA, allowing only water vapor to pass through it. Detailed experimental analysis revealed that the simulated contaminated water containing perfluorooctane sulfonic acid (PFOS) at a concentration of about 500 ng/L after MD treatment had a PFOS concentration of about 3 ng/L, which is the global environment. was below the standard.

ISOBE concludes by outlining future plans to improve MD purification methods. “Currently, simulated evaporation of PFAS contaminated water is achieved using heaters, relying on vacuum pumps to enhance the flow of water vapor. Switching to solar heating methods, no heater dependent power included Develop the system.”

In addition to developing a new MD method to purify PFAS-contaminated water, the researchers conducted a series of experiments containing lignin-derived adsorbents. They found that minimal activated carbon (treated with zinc chloride at a 1:3 ratio) could remove up to 99% of PFA within 10 minutes.

Overall, this study presents new, sustainable carbon-based materials that can promote the development of future cleanup technologies and solve important and sustainable environmental issues.