[1C13-18] Bentonite chemistry

4:15 PM - 4:30 PM JST(7:15 AM - 7:30 AM UTC)

[1C13] A Study on Swelling Pressure of Bentonite using Thermodynamic modelAcquisitions of Thermodynamic Data of Interlayer Water of Na-Montmorillonite and Model Evaluation

*Kazuki Nagamachi¹, Haruo Sato¹ (1. OKAYAMA UNIVERSITY)

Keywords:

Buffer material,Bentonite,Montmorillonite,Swelling Pressure,Thermodynamic model

We investigated a model describing the swelling characteristics of bentonite, the primary component of the buffer material used in geological disposal. Although numerous experimental measurements of the swelling pressure of Na-type bentonite have been reported, there are limitations, such as the types of bentonite and test conditions. While thermodynamic models for the interlayer water of montmorillonite are being developed as highly versatile models, thermodynamic data remain limited. In this study, we obtained thermodynamic data for Na-type montmorillonite interlayer water and analyzed the swelling pressure based on a thermodynamic model. We then evaluated the model’s practicability by comparing the results with measured values.