The city of Grand Rapids is interested in collaborating with a Lansing scientist who has developed a process that he says can destroy PFAS pollution in drinking water and wastewater, a hot-button issue locally and statewide.
Cory Rusinek, scientist with the Lansing laboratory of Fraunhofer USA Inc., said that scaling up his electrochemical process from laboratory to pilot plant hinges largely on obtaining grants he has requested from the federal government and other stakeholders.
But the process that uses electrodes coated with a film of boron-doped diamonds to rip apart PFAS with electricity is working daily at the Lansing lab, Rusinek said.
Grand Rapids is interested in offering Rusinek a place to locate the pilot plant.
“We are looking for a way to collaborate with him (Rusinek),” said Michael Lunn, utilities director for the city of Grand Rapids. “We’d like to help him get the process out of the lab and into the field.”
Lunn said city staff have met with Rusinek and viewed a video that details the process.
Along with other stakeholders, the city may play a role in helping Rusinek financially and by acting as the municipal utility sponsor for grants, according to Lunn. Rusinek apparently wasn’t eligible for a federal grant awarded earlier this year because he didn’t have an established relationship with a municipal water utility, Lunn said.
Rusinek said he has written grant applications to the U.S. Environmental Protection Agency and demonstrated his process about a month ago to Jillian Farkas, lead staffer on PFAS issues in the Washington, D.C. office of U.S. Sen. Gary Peters, D-Mich. In November, Peters convened a Senate subcommittee field summit in Grand Rapids to assess how the problem affects Michigan communities.
Farkas did not respond to inquiries about Rusinek’s process.
An EPA representative said Rusinek’s process is being researched by a collaboration between that agency, the Department of Defense and the Department of Energy.
The thorny problem of removing and destroying PFAS, or per- and polyfluoroalkyl substances, is more than academic for Michigan and at least 20 other states that are devoting resources to understanding the issue.
PFAS is a group of about 4,700 chemicals that have been used worldwide since the 1940s in a wide range of industrial applications and consumer products — everything from carpets to microwave popcorn bags.
PFAS are tough molecules to break down due to strong chemical bonds that fluorine forms with carbon and other elements. That stubborn stability that makes PFAS resistant to heat, water and oils presents a double-edged sword when ingested by the human body, where they accumulate in tissues rather than breaking down under normal biological processes.
Northern Kent County has several dump sites tainted with PFAS that are a result of manufacturing at Rockford-based Wolverine World Wide Inc. (NYSE: WWW), which used the chemicals as a coating to make footwear water repellant. Plainfield Township brought a new filtration system into operation in June to remove PFAS from the municipality’s water supply. As well, the city of Kalamazoo extended its water mains this summer to the nearby city of Parchment in response to a warning from state officials in July that residents not drink the water from municipal wells.
The state of Michigan lists 34 specific sites where it is investigating the presence of PFAS, not including at lakes and rivers such as Gilkey Creek in Genesee County and the Clinton River north of Detroit where the presence of PFAS is suspected.
The new filtering system in Plainfield Township illustrates the commercial difficulties of removing PFAS — and how valuable Rusinek’s system could be.
Plainfield Township is filtering the water through the use of granular activated carbon (GAC), which essentially removes the PFAS from water by acting as a molecular sieve. While GAC is effective in absorbing PFAS molecules, the process of filtration leaves the problem of how to dispose of the residue. GAC that is laden with PFAS can be reused — but it needs to be heated roughly to the same temperature as volcanic lava to burn off all the captured chemicals. Plainfield Township will ship its spent GAC to Pennsylvania to be regenerated in a special incinerator.
Another process called reverse-osmosis also can effectively filter PFAS from water, but the process can be slow, consume much more water than generated for use and still require prefiltration.
Rusinek said his process of electrochemical oxidation (EO) actually destroys the PFAS on-site, saving the costs of transport and regeneration of GAC in specially designed incinerators. It does so through the process of electrolysis, where molecules dissolved in water and even water itself can be torn apart with electricity.
To illustrate, connect two wires to the terminals of a common battery and insert the leads into a glass of water. After a time, bubbles of hydrogen will collect at the negative wire and oxygen will collect at the positive wire. Water — which is composed of hydrogen and oxygen atoms — has been torn apart by the direct current of the battery.
Rusinek’s process does this on a grand scale, specifically targeting PFAS. Researchers at the Fraunhofer Center for Coatings and Diamond Technologies on the campus of Michigan State University are designing and manufacturing custom electrodes made by depositing on metal a thin dense film of diamonds doped with boron.
“We make our electrodes using what you could call an absolutely massive toaster,” Rusinek said with a smile.
Researchers place uncoated metal in a chamber that they fill with a cocktail of gasses such as methane and diborane, and turn on high temperature heating elements. The carbon in the methane condenses on the electrode as diamond, along with atoms of boron.
At a lecture that he gave recently at the MSU Michigan Bioeconomy Institute in Holland to an audience of about 30 people, Rusinek emphasized repeatedly that no process alone — including his — will solve the problem of removing PFAS from drinking and wastewater and that any new processes will take years to develop to make them commercially feasible.
He sees his process as being very effective at destroying PFAS after they first have been concentrated from drinking and wastewater using ion-exchange resins, the same technology used every day in homes and industrial facilities to remove minerals such as calcium and magnesium from water.
“I think we can make very rapid progress in our EO technology because we know that it works,” said Rusinek, who holds a doctorate in analytical chemistry from the University of Cincinnati. “And I think Grand Rapids would be a great place for us to launch a pilot plant. Michael Lunn and his staff are really on top of the latest advances in PFAS remediation.
“Frankly, if I was going to have anyone treat my wastewater, it would be those guys.”
Editor’s note: This story has been updated to correct the spelling of Michael Lunn’s last name.