In previous articles I have written about the benefit of biochar as a soil additive and as a filter for neutralizing toxic chemicals. It could be easily made from our forest residual material which is often burned in the field. An article from UBC News describes yet another use of activated carbon for dealing with the PFAS chemicals.
According to the article, Chemical engineers at the University of British Columbia have developed a new treatment that traps and treats PFAS substances—widely known as “forever chemicals”—in a single, integrated system.
Per- and polyfluoroalkyl substances (PFAS) are widely used in manufacturing consumer goods like waterproof clothing and fire retardants due to their resistance to heat. However because of their resistance they are also pollutants, often ending up in surface and groundwater worldwide, where they have been linked to cancer, liver damage and other health issues.
“PFAS are notoriously difficult to break down, whether they’re in the environment or in the human body,” explained lead researcher Dr. Johan Foster, an associate professor of chemical and biological engineering in the faculty of applied science. “Our system will make it possible to remove and destroy these substances in the water supply before they can harm our health.” The UBC system combines an activated carbon filter with a special, patented catalyst that traps harmful chemicals and breaks them down into harmless components on the filter material. Scientists refer to this trapping of chemical components as adsorption.
“The whole process is fairly quick, depending on how much water you’re treating,” said Dr. Foster. “We can put huge volumes of water through this catalyst, and it will adsorb the PFAS and destroy it in a quick two-step process. Many existing solutions can only adsorb while others are designed to destroy the chemicals. Our catalyst system can do both, making it a long-term solution to the PFAS problem instead of just kicking the can down the road.”
Our catalyst can eliminate up to 90 per cent of forever chemicals in water in as little as three hours—significantly faster than comparable solutions on the market. And because it can be produced from forest or farm waste, it’s more economical and sustainable compared to the more complex and costly methods currently in use,” said Dr. Foster.
The research was supported by an NSERC Discovery grant and was published in Nature Communications Engineering.
The challenge of the government and the forest industry is how to encourage the production of biochar which is one of the best ways to sequester carbon as it acts as a soil amendment rather than ending up in the atmosphere as carbon dioxide. Considerable quantities of activated carbon will be needed when we move to the next phase of treating the wide variety of waste disposal systems with the carbon filter described above.
