The effects of crystallization and residual glass on the chemical durability of iron phosphate waste forms containing 40 wt% of a high MoO3 Collins-CLT waste

JOURNAL OF NUCLEAR MATERIALS

卷:500

Article

Hsu, Jen-Hsien¹  Bai, Jincheng¹  Kim, Cheol-Woon²  Brow, Richard K.¹  Szabo, Joe²  Zervos, Adam² 

[1] Missouri Univ Sci & Technol, Mat Res Ctr, Rolla, MO 65409 USA

[2] Mo Sci Corp, 4040 HyPoint North, Rolla, MO 65401 USA

关键词: Iron phosphate glass;    Waste form;    Nuclear waste;    Chemical durability;    Collins-CLT waste;   

DOI  :  10.1016/j.jnucmat.2018.01.005

来源: Elsevier

【 摘 要 】

The effects of cooling rate on the chemical durability of iron phosphate waste forms containing up to 40 wt% of a high MoO3 Collins-CLT waste simulant were determined at 90 degrees C using the product consistency test (PCT). The waste form, designated 40wt%-5, meets appropriate Department of Energy (DOE) standards when rapidly quenched from the melt (as-cast) and after slow cooling following the CCC (canister centerline cooling)-protocol, although the quenched glass is more durable. The analysis of samples from the vapor hydration test (VHT) and the aqueous corrosion test (differential recession test) reveals that rare earth orthophosphate (monazite) and Zr-pyrophosphate crystals that form on cooling are more durable than the residual glass in the 40wt%-5 waste form. The residual glass in the CCC-treated samples has a greater average phosphate chain length and a lower Fe/P ratio, and those contribute to its faster corrosion kinetics. (C) 2018 Elsevier B.V. All rights reserved.

【 授权许可】

Free