Application of surface complexation modeling on adsorption of uranium at water-solid interface: A review

Area of Science:

• Environmental Science
• Geochemistry
• Radiochemistry

Background:

• Accurate prediction of uranium adsorption at the water-mineral interface is crucial for safe geological disposal of radionuclides.
• Surface complexation modeling (SCM) is a key tool for simulating metal and metalloid adsorption.
• A comprehensive review of SCM applications for uranium adsorption is lacking.

Purpose of the Study:

• To systematically review the application of various SCMs for uranium adsorption.
• To provide guidelines for predicting uranium transport and fate in geological environments.

Main Methods:

• Summary of the rationale behind SCM, including constant-capacitance-model (CCM), diffuse-layer-model (DLM), and triple-layer-model (TLM).
• Detailed review of recent SCM applications for uranium adsorption on metal (hydr)oxides, clay minerals, and soil/sediments.

Main Results:

• SCM is extensively used to model uranium adsorption on diverse mineral surfaces.
• Various SCM approaches offer different levels of detail in simulating adsorption mechanisms.
• The review synthesizes recent findings on uranium adsorption across different geological materials.

Conclusions:

• This review provides a systematic overview of SCM for uranium adsorption.
• It highlights the utility of SCM in understanding uranium's environmental behavior.
• The findings offer valuable guidance for predicting long-term uranium fate in geological repositories.