Immobilization of radioactive waste in cement: Iodine binding by cementitious materials under highly alkaline conditions

Abstract

This work is directed to assess iodine interactions with hardened cement paste (HCP) under highly alkaline conditions (pH > 12) with/without a reductant. For this purpose, a series of Kd(distribution coefficient) experiments using127I as a tracer were performed. The Kdvalues of iodine were in the order of 172–1095 mL g–1in the batch experiment without a reductant, and in the order of 83–92 mL g–1in the experiment with a reductant. The percentage of iodine leached out from HCP throughout the experiment suggested its very strong binding with cementitious materials. The obtained results allow supposing that chemical speciation of iodine has influence on the interaction of iodine with HCP under highly alkaline conditions.

High Retention Immobilization of Iodine in B–Bi–Zn Oxide Glass Using Bi2O3 as a Stabilizer under a N2 Atmosphere

“…Immobilization of radioactive iodine waste into stable matrices (such as cements, glass, ceramics, and glass ceramics) was recognized as an effective strategy in the field of radioactive iodine waste treatment. Among the various matrices, glass was the most widely studied and applied. − Up to now, different glass systems have been designed and employed to immobilize iodine waste.…”