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Introduction
Nuclear energy is a potential solution for addressing the global energy crisis and reducing CO₂ emissions [1]. In 2021, it contributed to nearly 15% of global electricity production, with 437 reactors in operation worldwide. However, this industry, along with others, generates radioactive waste [2]. Radioactive waste is generated from chemical sludges, reactor decommissioning, fission products and spent fuel; these wastes contain hazardous radioactive materials that can negatively impact the environment and all living organisms for hundreds of years. Nuclear waste can be characterized based on their level of activity as follows: low-level radioactive waste (LLW), intermediate-level radioactive waste (ILW) and high-level radioactive waste (HLW). The management of radioactive waste poses a significant challenge for nuclear power plants and the nuclear-based technologies. Each type of radioactive wastes requires different method of management, and should be safely and properly disposed to promote a safe and a sustainable nuclear power program. Depending on the category of radioactive waste, the disposal can be carried out in landfill disposal, shallow level disposal and deep geological repositories. The multi-barrier system is composed of several layers of protection. The first layer is the waste form itself, followed by the second layer, which is the HLW container. The third layer consists of an engineered barrier, and the fourth layer is a geological barrier. Immobilization is one of the waste management treatment techniques that involves transforming radioactive waste into a specific waste-form through solidification, embedding, or encapsulation [2]. The objective is to dilute the radioactivity and minimize the risk of radionuclide migration or dispersion into the environment during activities such as handling, transportation, storage, or disposal [3]. Different types of materials are commonly used in radioactive waste management: cementitious materials typically Ordinary Portland cement (OPC), bitumen and glass are widely used to solidify LLW and ILW liquids [3, 4-5], steel is used for HLW management and underground tunnel lining [6]. OPC was proven successful for this application and is considered a mature ready to be used technology. However, cement solidification is still facing some challenges regarding the durability of the material that is prone to degradation in contact with acids and at extreme temperature conditions [7]; radionuclides in solidified cement matrices are primarily retained through chemisorption and physical encapsulation. However, durability...