Gels, coatings and foams for radioactive surface decontamination: State of the art and challenges for the nuclear industry

The decontamination of solid surfaces is an important process in nuclear decommissioning, but also during regular maintenance operations in active nuclear facilities. The outcomes of these operations are highly variable, depending among others on the nature of the substrate, the type of contamination, and the amount and nature of the secondary waste generated. A wide range of decontamination technologies have therefore been developed, based on mechanical (cutting, abrasion, etc.), laser (ablation, stripping) or chemical (washing, wiping) processes. The focus of this review is on liquids that can form gels, strippable coatings, and foams that can effectively remove contamination for surfaces relevant to the nuclear industry. Its aim is particularly to highlight the importance of the formulation step and guide the future development of gels and foams for nuclear decontamination. Recent innovative formulations are presented along with new perspectives and challenges for these technologies.