Experimental and modeling studies on iron-bentonite interactions

Sasamoto, Hiroshi; Wilson, J.*; Sato, Hisao*; Sazarashi, Masami

no journal, , 

The proposed repository design for high-level radioactive waste in Japan includes iron containers surrounded by a bentonite buffer. Interactions of iron-bentonite (I/B) materials may lead to the adverse transformation of smectite to phases with a limited capacity to swell. Batch experiments that included native iron powder and bentonite and column experiments whereby compacted bentonites were reacted with embedded iron coupons were conducted in order to evaluate the effects of environmental parameters on I/B interactions. Additionally, several model simulations have been produced in order to evaluate the factors influencing the nature of bentonite alteration in the presence of iron. The dominant process of interest over performance assessment timescales was estimated as the results of variant simulations.