Ruzic leads plasma project to streamline metal cleaning

11/30/2021

Phillip Kisubika

Ruzic leads plasma project to streamline metal cleaning

A new project undertaken by NPRE professors David Ruzic and Mohan Sankaran seeks to develop a process that simplifies the cleaning and treating of steel using plasmas.

“This came from a prior project we had with SERDP (Strategic Environmental Research and Development Program),” Ruzic, the department’s Abel Bliss Professor of Engineering, said.

In various forms of construction, before steel can be repurposed, it must be cleaned, and layers of paint and other chemicals usually need to be removed before being re-treated.

“Some of that infrastructure is exposed to harsh environments such as salt water and cannot be easily replaced or brought to a facility to clean – therefore, they need approaches to clean them remotely,” Sankaran said. 

“Every one of those steps causes chemical waste, and while it works, these days, the military has to pay to clean up all that waste,” Ruzic said. “And everyone dealing with these harsh chemicals have to be fully protected, and all that adds a lot of cost…I can use plasmas to clean the metal and cut down the process and produce no waste.”

Further, not only would you not have to ship metals from place to place, an apparatus could be created to transport where cleaning is necessary and save on those costs.

The objective of this effort—which has been funded at $200,000 per year for two years—is to develop and test a chemical waste-free approach to treating steel that cleans the surface, to either pretreat or remove existing foreign material layers, and subsequently provides corrosion protection and enhances the adhesion of paints/primers.

Ruzic said this was accomplished in the previous SERDP project, which took place over the last three years. “It’s a tall order because all the work we did with SERDP was with aluminum,” Ruzic said. “Steel is very different. The cool thing is if this does work, there’s a direct path to actually having this go into use.”

“My role is to bring expertise in plasma chemistry to the team,” Sankaran said. “For example, one of the critical parts of the project will be to try to remove rust which is basically an oxidized form of iron.  I will be developing the gas-phase chemistry that can produce the reactive radicals necessary to remove and/or reduce the oxide back to metallic iron in the steel.” 

The current project will be done in conjunction with the Construction Engineering Research Laboratory, an Army Corps of Engineers lab in Champaign that conveniently happens to be the one in charge of painting steel. “It was a natural fit,” Ruzic said.