By Marisa Sloan
Over 60 years ago, the revolutionary “nonstick” Teflon pan was first unveiled. American households would be forever changed by the invention, although not for the better.
The pan’s slippery coating was made using perfluorooctanoic acid, one of a class of over 6,000 extremely durable, man-made chemicals known as PFAS. Before scientists linked them to adverse human health effects, these chemicals were used for decades afterward in a wide range of products, from food packaging to firefighting foam.
Although they are no longer manufactured in the United States, these “forever” chemicals remain widespread in the environment and in animals because their super strong bonds don’t break down naturally. According to the U.S. Centers for Disease Control and Prevention, nearly all Americans have a measurable amount of PFAS in their blood — most likely as a result of contaminated water or food. In recent years, this exposure has been linked to increased risk of cancer as well as issues with growth and development, reproduction, the immune system, and the liver.
Techniques to remove PFAS from water exist, but scientists are still on the search for a solution that will permanently prevent the chemicals from being recycled back into the environment. With this in mind, a group of CEOs came together during the inaugural Chicago Water Week last month to discuss the new technologies their companies are developing to destroy PFAS in water.
Ovector LLC is advancing plasma — a fourth state of matter found in everything from the tails of comets to neon signs — as a water treatment technology.
The company’s flagship technology is the Plasma Vortex, affectionately referred to as “lightning in a bottle.” It was developed through federal research contracts with the U.S. Environmental Protection Agency and Air Force.
“If you energize a gas until some of the electrons fall off it becomes a plasma, like the sun or lightning, which is luminous and highly energetic,” said Daniel Cho, CEO of Onvector.
When the plasma’s energetic electrons come into contact with contaminated water, they latch onto the PFAS molecule and make it unstable. After a short while, its super strong bonds break down. Cho said the system can currently treat about 30 gallons of water per minute.
“Plasma water treatment technology is obscure and has low acceptance because no one, until now, has cracked the code,” Cho said. “We’ve overcome all of the challenges.”
Although plasma can break down PFAS much faster than some other technologies, a common criticism is its inability to completely degrade molecules with exceptionally long chains of carbon and fluorine atoms. According to Cho, Onvector has developed a solution for this.
“This is the beginning of a seismic change,” Cho said. “Because of technology and innovation, ‘forever’ chemicals aren’t going to be forever anymore.”
Aquagga Inc., a collaboration between Idaho National Laboratory and multiple universities, is cooking up a hydrothermal solution to the PFAS problem.
“It’s like a pressure cooker on steroids,” co-founder Dr. Brian Pinkard said. “We heat it up, let the PFAS cook for a little while, and then we cool it back down and collect the liquid products.”
According to Pinkard, the high temperatures break PFAS molecules into small amounts of nontoxic fluoride and carbon dioxide in a process called mineralization. Because the system operates at such a high pressure, PFAS remains in the liquid phase throughout the entire process and loses the chance to escape as a gas before being broken down.
And it’s on wheels. Pinkard expects the system will be used to destroy PFAS at the source, whether that be at military bases or airports. Its mobility may make it more enticing to facilities with smaller amounts of PFAS contamination that don’t necessarily warrant a permanent installation.
“Folks need solutions that are scalable, affordable and can be deployed on-site on active remediation projects,” he said.
There are, however, some issues. Pinkard expects the system will be used in combination with existing PFAS removal technologies, such as granulated activated carbon or reverse osmosis, which pull the toxic chemicals out of water and concentrate them within a brine that can then be heated and pressurized.
But brine is more than just salty water. It’s toxic and is known to wreak havoc on ecosystems. Dilution solutions exist, but they can be costly and the additional step may negate the convenience that Aquagga is attempting to sell.
Regardless, Pinkard is optimistic. He said the startup expects to pilot its technology within the next year.
Zyvant Research & Innovations
Electrochemistry is used in a variety of everyday devices, from lithium batteries to fuel cells. Now, Dr. Brian Chaplin and his colleagues at the University of Illinois at Chicago have developed a reactive electrochemical membrane he said is capable of destroying over 99% of PFAS compounds.
“That’s really what you want in a treatment technology for PFAS because these things are going to be around for a long time and we need something to take them out of the environmental cycle,” Chaplin said.
Zyvant Research & Innovations, a company co-founded by Chaplin and his wife, is currently negotiating with the university to become the licensee of his patented technology.
To understand how his electrochemical membrane works, it may help to picture an electric Brita filter. The membrane traps any large PFAS molecules in the contaminated water, and the applied electric current breaks them down.
“We also have shown the ability to disinfect bacteria and viruses,” Chaplin said. “It really is multifaceted.”
Like Aquagga’s hydrothermal technology, Chaplin said his technique results in complete mineralization. However, it accomplishes this with far lower levels of energy consumption than other PFAS destruction technologies, including hydrothermal decomposition.
“These problems are currently lacking a technology solution that I think everyone is excited about,” he said.
Chaplin said he hopes his technology can become that solution not only for PFAS, but for other water contaminants as well. It is currently in the very early stages of development; a prototype exists at the laboratory scale, and Chaplin is looking to pilot within the next two years.
Marisa Sloan is a health, environment, and science reporter at Medill. You can follow her on Twitter at @Sloan_Marisa.