Early-stage rust surface chemistry
A recent report details the results of testing by the Michigan Technological University into the surface chemistry of early-stage rust and the development of a more precise method to observe the formation of iron mineral corrosion with water and oxygen.
The study, “Effect of Cations on the Oxidation and Atmospheric Corrosion of Iron Interfaces to Minerals,” was recently published in The Journal of Physical Chemistry A, and the researchers hope that a better understanding of this process will aid with carbon dioxide capture, uncover polluted water systems and improve infrastructure like bridges and pipelines.
According to MTU, the main finding is that cations in solution, such as positively charged sodium or calcium ions, influence the type of carbonate films grown when exposed to air. With gradual exposure to oxygen and carbon dioxide, the carbonate films produced are specific to the cation.
The new technique is a three-stage process, assessing changes to the electrolyte composition and using oxygen and carbon dioxide from air as a reactant, to observe real-time formation of the different minerals like rust observed at the air-liquid-solid interface.
