The technology effectively removes and destroys synthetic organofluorine chemicals (PFAS).

Researchers from the Faculty of Civil and Environmental Engineering at the Technion Israel Institute of Technology have developed an innovative technology to remove hazardous contaminants from drinking water. The study was led by Drs Adi Radian and Samapti Kundu.

PFAS are a family of problematic pollutants, also known as “timeless chemicals” due to their chemical and environmental stability.

These substances can be found in products such as Teflon coating for pans, fire-fighting foam, flame retardants, and water-repellent additives. They enter the groundwater in various ways. Due to their chemical resistance, they remain intact in the ground for a long time, which leads to extensive contamination of drinking sources. This, in turn, significantly increases the negative impact on the person.

International studies have demonstrated many health risks associated with exposure to PFAS, including cancer, heart and liver disease, fertility problems, birth defects, and damage to the immune system.

Removal of these substances from drinking water is now carried out using relatively simple and inexpensive adsorption methods. However, these methods are not efficient enough, and most importantly, they only transfer pollutants from water to the adsorbing material, which requires additional stages of purification from adsorbed toxic substances. In addition, these methods are not selective: they can also remove substances that are essential for people’s health.

Two new and promising solutions involve the use of oxidation processes and targeted polymers that effectively adsorb contaminants. However, these technologies have not given satisfactory results so far.

A new study explored the possibility of combining the two methods – separating contaminants with special polymers and then using advanced oxidation processes to eliminate them. The findings indicate that proper planning results in high efficiency over a wide range of acidity (pH) and salinity.

The method allows the removal of seven types of PFAS, even when they are all in one unit of liquid, with an efficiency approaching 90% within minutes.

The described system is based on natural materials that are both safe and inexpensive.

The researchers used ubiquitous soil minerals iron oxides and clays along with cyclodextrin polymers. The clay-iron-polymer composites act as accelerators that hold the PFAS on the surface and then accelerate the oxidation process that breaks down the contaminants into non-toxic substances (fluorine ions, water and carbon dioxide). The combination effectively removes PFAS and does not release unwanted substances into drinking water.