Monitoring and understanding of corrosion on nuclear sites is key to safe asset management (predicting plant life, assessing efficacy of corrosion inhibitors for plant lifetime extension) and supporting informed choice of decontamination methods for steels due for decommissioning. Recent advances in Quartz Crystal Nanobalance (QCN) technology offer a means to monitor corrosion in-situ in radiologically harsh environments, in real time and with high sensitivity.
Oxalic acid has been widely used in nuclear facilities as a corrosion inhibitor for carbon steels and as a decontamination cleaning agent due to its ability to remove rust from the surface of ferritic metals and alloys. As an exemplar system for decontamination, the corrosion behavior of pure iron samples in 1 wt% oxalic acid solution has, for the first time, been measured in simulated radioactive environments in real time, in situ using the QCN. Results show that the QCN is a promising tool for studying the efficacy of oxalic acid decontamination agent formulations with the sensor providing useful mechanistic information regarding decontaminating agent mode-of-action derived from the mass change (gain or loss) in real time when a quartz crystal is immersed in oxalic acid solution in simulated and non–simulated radioactive environments.