No. 331: Eliminate rust using plasma under normal atmospheric pressure (October 19, 2011)

A research team led by a professor of Tokyo Institute of Technology developed a method to eliminate rust on the metal surface instantaneously using an apparatus that generates plasma under normal atmospheric pressure. It produced a mixed gas of argon and hydrogen and transformed it to a plasma state, and sprayed it on a copper plate covered with copper oxide that is the substance of rust at 200 degrees centigrade. The copper oxide and hydrogen changed to water and copper through a chemical reaction and eliminated the copper oxide film on the surface of the copper plate. The research team reduced the thickness of the rust from 10 nanometers to 2 nanometers. No large equipment like a vacuum unit is required because the newly developed method allows for the process under normal atmospheric pressure.

Currently, the chemical treatment method that uses acid and the mechanical method that needs polishing are widespread to eliminate rust. However, these two methods create a problem with the treatment of waste solution. In addition, the plasma treatment under low pressure requires continuous spraying of plasma on the target rust for several minutes.