Doctor of Philosophy (PhD)


Environmental Sciences

Document Type



Severe nuclear accidents, including the Fukushima nuclear power plant accident, can lead to the discharge of large amounts of radionuclides into aquatic environments. Some radionuclides such as 137Cs and 90Sr have long half-lives and can remain in the environment for a long period of time. These radionuclides can be detrimental to humans and the environments because they can cause human and environmental exposure to ionizing radiation and because they can be bioaccumulated and biomagnified. Therefore, in case of a severe accident and a radioactive spill, it is important to quickly clean up and treat radioactively contaminated water to protect public health and aquatic ecosystems from unwanted radiation exposure.

Ion separation technologies can play a critical role in the cleanup and treatment of radioactive water because most radionuclides in water are present as radioactive ions. Conventional ion separation technologies are typically used to decontaminate radioactive water, but many of these technologies are energy-consuming. Capacitive deionization (CDI) and membrane CDI (MCDI) are alternatives to the conventional technologies. CDI and MCDI are based on electrosorption and are less energy-intensive. However, because they have been designed and investigated for brackish water desalination, CDI and MCDI are not normally considered for the removal of radioactive ions from aqueous solutions.

Toward more efficient and effective cleanup and treatment of radioactively contaminated water, this study aims at investigating the potential of CDI and MCDI for the removal of radioactive ions from aqueous solutions. Modeling and experimental investigations are performed along with techno-economic analysis to assess the applicability of CDI and MCDI for radionuclide separation. Carbon electrodes covered with carboxylic functional groups are employed to enhance their removal efficiency.

This study contributes toward better protection of the public health and aquatic environments against radioactive contamination in water and the developed CDI and MCDI can be used to separate radioactive ions from aqueous environments. The results are also useful in expanding the applicability of CDI and MCDI to the treatment of various wastewater and high-salinity solutions.



Committee Chair

Kim, Yong-Ha



Available for download on Thursday, April 02, 2026