Novel approaches for cleaning up radionuclide nanoparticle pollutants in the environment

Colloids and Nanoparticles (NPs) have potential to significantly enhance the mobility of radionuclides in the environment, either through the adsorption of radionuclides onto their surfaces, or through the enhanced transport of NPs and colloids composed of radionuclides. However, nanoparticles and colloids can become immobilized inside growing minerals by a process known as occlusion, which occurs when the growing mineral surface engulfs the particle. This process would immobilize and thus reduce the transport of NP/Colloid associated radionuclides.

This process has potential to be both a significant natural, and engineered process, but has yet to be explored in systems relevant to nuclear decommissioning and disposal. Natural mineral precipitation is driven both abiotically and through microbial processes, and thus has potential to capture NPs and colloids this way. In addition, the process has potential to act as an engineered remediation approach, where microbial mineral precipitation is used to purposefully scavenge nanoparticles.

The program will explore the ability of a range of relevant minerals, including carbonates, iron-oxides and phosphates to capture NPs/colloids. Model NPs will be used to explore the impact of surface interactions, then moving onto NPs/colloids relevant to natural systems such as nano-clays, iron and silicates. The research will also explore whether radionuclides adsorbed to particle surfaces are released during this process.